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1.
Sensors (Basel) ; 22(8)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35458868

RESUMO

As a detection method, X-ray Computed Tomography (CT) technology has the advantages of clear imaging, short detection time, and low detection cost. This makes it more widely used in clinical disease screening, detection, and disease tracking. This study exploits the ability of sparse representation to learn sparse transformations of information and combines it with image decomposition theory. The structural information of low-dose CT images is separated from noise and artifact information, and the sparse expression of sparse transformation is used to improve the imaging effect. In this paper, two different learned sparse transformations are used. The first covers more organizational information about the scanned object. The other can cover more noise artifacts. Both methods can improve the ability to learn sparse transformations to express various image information. Experimental results show that the algorithm is effective.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Algoritmos , Artefatos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Tomografia Computadorizada por Raios X/métodos
2.
Sensors (Basel) ; 21(22)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34833523

RESUMO

A bilateral neural network adaptive controller is designed for a class of teleoperation systems with constant time delay, external disturbance and internal friction. The stability of the teleoperation force feedback system with constant communication channel delay and nonlinear, complex, and uncertain constant time delay is guaranteed, and its tracking performance is improved. In the controller design process, the neural network method is used to approximate the system model, and the unknown internal friction and external disturbance of the system are estimated by the adaptive method, so as to avoid the influence of nonlinear uncertainties on the system.


Assuntos
Fenômenos Mecânicos , Redes Neurais de Computação , Retroalimentação , Dinâmica não Linear , Incerteza
3.
Sensors (Basel) ; 21(22)2021 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-34833646

RESUMO

At present, feature-based 3D reconstruction and tracking technology is widely applied in the medical field. In minimally invasive surgery, the surgeon can achieve three-dimensional reconstruction through the images obtained by the endoscope in the human body, restore the three-dimensional scene of the area to be operated on, and track the motion of the soft tissue surface. This enables doctors to have a clearer understanding of the location depth of the surgical area, greatly reducing the negative impact of 2D image defects and ensuring smooth operation. In this study, firstly, the 3D coordinates of each feature point are calculated by using the parameters of the parallel binocular endoscope and the spatial geometric constraints. At the same time, the discrete feature points are divided into multiple triangles using the Delaunay triangulation method. Then, the 3D coordinates of feature points and the division results of each triangle are combined to complete the 3D surface reconstruction. Combined with the feature matching method based on convolutional neural network, feature tracking is realized by calculating the three-dimensional coordinate changes of the same feature point in different frames. Finally, experiments are carried out on the endoscope image to complete the 3D surface reconstruction and feature tracking.


Assuntos
Algoritmos , Imageamento Tridimensional , Endoscópios , Humanos , Redes Neurais de Computação , Silicones
4.
Gynecol Endocrinol ; 33(2): 128-131, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27684473

RESUMO

Chorioamnionitis is associated with an increased risk of spontaneous preterm birth. The aim of this study was to investigate the serum levels of high mobility group box-1 (HMGB1) in pregnancies with histological chorioamnionitis (HCA)-associated preterm labor (PTL) with intact membranes or preterm premature rupture of membranes (PPROM), and to access the role of serum HMGB1 in HCA and HCA-associated PTL. A total of 190 pregnant women were enrolled in this study: PLT patients with (n = 28) or without HCA (n = 36), PPROM patients with (n = 26) or without HCA (n = 65), and non-HCA PTL controls (n = 35). Maternal serum levels of HMGB1 were measured by enzyme-linked immunosorbent assay. Serum HMGB1 levels were significantly higher in PTL or PPROM patients than in control group (p < 0.01, respectively). The PPROM patients also exhibited higher serum HMGB1 levels compared to PTL patients (p = 0.015). HCA patients were characterized by significantly increased levels of serum HMGB1 when compared with non-HCA patients (p < 0.01). Therefore, maternal serum HMGB1 may become a potential biomarker of HCA and HCA-associated PTL.


Assuntos
Corioamnionite/sangue , Ruptura Prematura de Membranas Fetais/sangue , Proteína HMGB1/sangue , Trabalho de Parto Prematuro/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Gravidez
5.
Tumour Biol ; 37(1): 239-51, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26198045

RESUMO

MicroRNAs (miRNAs) are a class of noncoding RNAs and function as key regulators of gene expression at the post-transcriptional level. In this study, we found that miR-495 reduces cell growth, induces apoptosis and suppresses the migration of endometrial cancer by directly inhibiting FOXC1 expression. Further analysis revealed that FOXC1 promotes growth and migration and functions as an oncogene in vitro. FOXC1 overexpression reversed the cellular responses mediated by miR-495 in endometrial cancer cells. We also found that miR-495 suppresses the growth of endometrial cancer in vivo. Altogether, these results indicate that miR-495 acts as a tumour suppressor gene by targeting FOXC1 at the post-transcriptional level in endometrial cancer.


Assuntos
Neoplasias do Endométrio/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Oncogenes , Proteínas Supressoras de Tumor/metabolismo , Regiões 3' não Traduzidas , Animais , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Regulação para Baixo , Feminino , Citometria de Fluxo , Perfilação da Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/metabolismo , Humanos , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase em Tempo Real
6.
Arch Gynecol Obstet ; 293(5): 1125-35, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26879955

RESUMO

PURPOSE: MicroRNAs (miRNAs) are small non-coding RNA molecules that play critical roles in post-transcriptional gene expression regulation. The aim of this study was to identify differentially expressed miRNAs in decidua and villus of recurrent miscarriage (RM) patients. METHODS: Participants were recruited at the outpatient Department of Gynecology and Obstetrics, The Second Hospital of Tianjin Medical University, China. Decidua and villus tissues were collected by curettage from recruited RM patients and normal pregnant women with their informed consent. MiRNAs expression profiles in decidua or villus were respectively determined by the deep-sequencing analysis. The predicated target genes of these differentially expressed miRNAs were analyzed by miRWalk. The differential expressions of four miRNAs in decidua and four miRNAs in villus between the six pairs of RM patients and normal pregnant women were confirmed by qRT-PCR analysis. The expression patterns of two predicated target genes, Bcl-2 and Pten, in the same six pairs of decidual or villus tissues were detected by Western blotting analysis, respectively. RESULTS: Totally 18 RM patients and 15 normal pregnant women were recruited. Thirty-two miRNAs in decidua and four miRNAs in villus of RM patients were screened out to be significantly up-regulated compared to that of normal pregnant women, and five miRNAs in villus of RM patients were screened out to be remarkably down-regulated compared to that of normal pregnant women (P value < 0.05 and Fold change >2). These differentially expressed miRNAs were predicted to target a large number of genes that involved in cell apoptosis, p53 signaling pathway, cell cycle and other cellular bio-functions. Differential expressions of hsa-miR-516a-5p, -517a-3p, -519a-3p and -519d in decidua, as well as hsa-miR-1, -372, -100-5p and -146a-5p in villus, were validated by qRT-PCR analysis. In the decidual of RM patients, expression of hsa-miR-516a-5p, -517a-3p, -519a-3p and -519d were significantly up-regulated compared to normal pregnancy. In the villi of RM patients, expression of hsa-miR-100 and -146a-5p were significantly higher, while hsa-miR-1 and -372 were significantly lower compared to normal pregnancy. Furthermore, the expression of Bcl-2 and Pten, a predicated target gene of hsa-miR-1 or hsa-miR-372 respectively, was significantly up-regulated in the villi of RM patients. CONCLUSIONS: These data suggested that the pathogenic process of RM might be associated with the alteration of miRNAs expression profiles in decidua and villus. Especially, the aberrant placental expression of hsa-miR-1 and -372 might be involved in the progression of RM, but need to be further investigated by larger studies in the future.


Assuntos
Aborto Habitual/genética , Vilosidades Coriônicas/metabolismo , Decídua/metabolismo , Perfilação da Expressão Gênica/métodos , MicroRNAs/análise , Placenta/química , Adulto , China , Vilosidades Coriônicas/química , Decídua/química , Regulação para Baixo , Feminino , Regulação da Expressão Gênica , Marcadores Genéticos , Humanos , Placenta/patologia , Placenta/fisiopatologia , Gravidez , Regulação para Cima
7.
Eur J Gynaecol Oncol ; 37(4): 499-503, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-29894074

RESUMO

PURPOSE: To assess the complications and clinical outcomes of concurrent chemoradiotherapy (CCRT) or pure radiotherapy (RT) in local advanced cervical carcinoma (LACC) patients. MATERIALS AND METHODS: A retrospective study was carried out in 113 consecutive LACC (FIGO Stage IB2-IIIB) patients, of whom 68 received CCRT; the others received pure RT. Five-year overall survival (OS) and the incidence, type, and severity of postoperative complications were analyzed. RESULTS: The five-year survival rate for CCRT and pure RT were 67.7% and 46.8%, respectively (p = 0.018). The incidences of bone marrow suppression and gastrointestinal reaction for CCRT and pure RT were 100% vs. 88.89% (p < 0.001) and 70.6% vs. 33.33% (p < 0.001). Only 16.18% patients received CCRT developed chronic radiation enteritis, and 4.35% developed chronic radiation cystitis. While 11.11% patients received pure RT experienced chronic radiation enteritis (p = 0.449), 4.44% experienced chronic radiation cystitis (p = 0.312). CONCLUSIONS: This retrospective study demonstrated that CCRT followed by radical surgery achieved a better outcome compared with pure RT in LACC patients, but could apparently rise the incidence and severity of hematologic and gastrointestinal toxicity.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Quimiorradioterapia/métodos , Lesões por Radiação/etiologia , Neoplasias do Colo do Útero/radioterapia , Adulto , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia/efeitos adversos , Terapia Combinada , Cistite/etiologia , Intervalo Livre de Doença , Enterite/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias do Colo do Útero/patologia
8.
Zhonghua Yi Xue Za Zhi ; 95(47): 3829-32, 2015 Dec 15.
Artigo em Zh | MEDLINE | ID: mdl-27337799

RESUMO

OBJECTIVE: To observe the effect of follicular fluid IL-6, TNF-α on the clinical outcome of in vitro fertilization and embryo transfer (IVF-ET) in patients with ovarian endometriosis. METHOD: From June 2013 to June 2014, the data of 64 (from Tangshan Maternal and Child Health Hospital IVF center) ovarian endometriosis patients was analyzed retrospectively. 58 infertility cases caused by male side were used as control group. Oocyte retrieval rate, M II oocytes rate, fertilization rate, recovery-intracytoplasmic sperm injection (R-ICSI) rate, good quality embryo rate, biochemical pregnancy rate and clinical pregnancy rate were analyzed and compared between two groups. Changes in the expression of follicular fluid IL-6, TNF-α were detected. RESULTS: Oocyte retrieval rate, M II oocytes rate, fertilization rate, good quality embryo rate, biochemical pregnancy rate and clinical pregnancy rate in ovarian endometriosis group were significantly lower than those in the control group (all P < 0.05), while R-ICSI rate increased in ovarian endometriosis group compared with control group (P < 0.05). IL-6, TNF-α expressions of follicular fluid were higher in affected side of ovarian endometriosis patients than those in the unaffected side and those in control group. CONCLUSION: Inflammation microenvironment of the follicular fluid may influence IVF-ET outcomes in ovarian endometriosis patients.


Assuntos
Endometriose/patologia , Fertilização in vitro , Líquido Folicular/química , Infertilidade Feminina/patologia , Inflamação/patologia , Estudos de Casos e Controles , Transferência Embrionária , Feminino , Humanos , Interleucina-6/química , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Injeções de Esperma Intracitoplásmicas , Fator de Necrose Tumoral alfa/química
9.
Zhonghua Yi Xue Za Zhi ; 94(11): 848-51, 2014 Mar 25.
Artigo em Zh | MEDLINE | ID: mdl-24854754

RESUMO

OBJECTIVE: To evaluate the cause of infertility and tubal abnormality in women of tubal pregnancy after conservative treatment with laparotomy or laparoscopy through a combination of laparoscopy, hysteroscopic tubal catheterization and hydrotubation. METHODS: Laparoscopy was performed to observe pelvic adhesions, tube shape, fimbriated extremity of fallopian and other factors related with infertility for 37 inpatients with infertility after tubal pregnancy and undergoing conservative surgery during December 2008 and October 2010. Meanwhile, hysteroscopic tubal catheterization and hydrotubation were performed with laparoscopy to examine tube patency. RESULTS: Among them, 97.3% had tube infertility caused by tube abnormality and adhesions, or tube obstruction alone or concurrently. For all tubes, tube obstruction accounted for 79.7% (59/74) , fimbrial occlusion of fallopian tube 54.1% (40/74) and tube abnormality 52.7% (39/74) . Pelvic adhesion occurred at a rate of 89.2% and there were I degree (21.6%), II degree (32.4%), III degree (35.1%) and IV degree (0). For tubes with pregnancy history, 48.6% showed tube abnormality, 45.9% fimbrial occlusion of fallopian tube and 75.7% (28/37) tube obstruction. Comparatively, for the tubes without pregnancy history, 56.8%showed tube abnormality, 62.2%fimbrial occlusion of fallopian tube and 86.5%tube obstruction. No significant difference existed in tube shape, umbrella end and tube obstruction between the tubes with pregnancy history and those without pregnancy history. Neither statistically significant difference was found in adhesion degree, tube shape, umbrella end and tube obstruction of diseased and normal tubes between laparotomy and laparoscopy groups. CONCLUSION: Infertility of women after tubal pregnancy and conservative surgery is mainly caused by abnormal tube including pelvic adhesion, tube morphological abnormality and tube obstruction. No marked inter-group difference exists in fertility damage after conservative surgery with laparotomy or laparoscopy.


Assuntos
Infertilidade Feminina/cirurgia , Gravidez Tubária/cirurgia , Adulto , Tubas Uterinas/patologia , Feminino , Humanos , Laparoscopia , Gravidez , Reoperação , Adulto Jovem
10.
Sci Total Environ ; 912: 169356, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38110091

RESUMO

As the pursuit of "carbon neutrality" gains momentum, the emphasis on low-carbon solutions, emphasizing energy conservation and resource reuse, has introduced fresh challenges to conventional wastewater treatment approaches. Precisely evaluating carbon emissions in urban water supply and drainage systems, wastewater treatment plants, and establishing carbon-neutral operating models has become a pivotal concern in the future of wastewater treatment. Regrettably, limited research has been devoted to carbon accounting and the development of carbon-neutral strategies for wastewater treatment. In this review, to facilitate comprehensive carbon accounting, we initially recognizes direct and indirect carbon emission sources in the wastewater treatment process. We then provide an overview of several major carbon accounting methods and propose a carbon accounting framework. Furthermore, we advocate for a systemic perspective, highlighting that achieving carbon neutrality in wastewater treatment extends beyond the boundaries of wastewater treatment plants. We assess current technical measures both within and outside the plants that contribute to achieving carbon-neutral operations. Encouraging the application of intelligent algorithms for the multifaceted monitoring and control of wastewater treatment processes is paramount. Supporting resource and energy recycling is also essential, as is recognizing the benefits of synergistic wastewater treatment technologies. We advocate a systematic, multi-level planning approach that takes into account a wide range of factors. Our goal is to offer valuable insights and support for the practical implementation of water environment management within the framework of carbon neutrality, and to advance sustainable socio-economic development and contribute to a more environmentally responsible future.

11.
J Cell Biochem ; 114(7): 1464-73, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23296900

RESUMO

As an important tumor suppressor, programmed cell death 4 (PDCD4) influences transcription and translation of multiple genes, and modulates different signal transduction pathways. However, the upstream regulation of this gene is largely unknown. In this study, we found that microRNA-182 (miRNA-182, miR-182) was upregulated, whereas PDCD4 was downregulated in ovarian cancer tissues and cell lines. Blocking or increase of miR-182 in ovarian cancer cell lines led to an opposite alteration of endogenous PDCD4 protein level. Using fluorescent reporter assay, we confirmed the direct and negative regulation of PDCD4 by miR-182, which was dependent on the predicted miR-182 binding site within PDCD4 3' untranslated region (3' UTR). MTT and colony formation assays suggested that miR-182 blockage suppressed, whereas miR-182 mimics enhanced viability and colony formation of ovarian cancer cells. These effects may partly be attributed to the cell cycle promotion activity of miR-182. miR-182 also contributed to migration and invasion activities of ovarian cancer cells. Furthermore, miR-182 reduced the chemosensitivity of ovarian cancer cells to CDDP and Taxol, possibly by its anti-apoptosis activity. Importantly, all the alterations of the above cellular phenotypes by blocking or enhancing of miR-182 could be alleviated by subsequent suppression or ectopic expression of its target PDCD4, respectively. We conclude that in ovarian cancer cells, miR-182 acts as an oncogenic miRNA by directly and negatively regulating PDCD4.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , MicroRNAs/metabolismo , Neoplasias Ovarianas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Reguladoras de Apoptose/genética , Northern Blotting , Western Blotting , Linhagem Celular Tumoral , Feminino , Citometria de Fluxo , Humanos , Técnicas In Vitro , MicroRNAs/genética , Neoplasias Ovarianas/genética , Proteínas de Ligação a RNA/genética , Cicatrização/genética , Cicatrização/fisiologia
12.
Zhonghua Fu Chan Ke Za Zhi ; 48(6): 447-52, 2013 Jun.
Artigo em Zh | MEDLINE | ID: mdl-24103125

RESUMO

OBJECTIVE: To study the role of epidermal growth factor (EGF) , epidermal growth factor receptor(EGFR), extracellular signal-regulated kinase 1/2 (p-ERK1/2) in the pathogenesis of endometriosis under estrogen deprivation conditions. METHODS: The estrogen was quickly-stripped in medium and the female nude mice were castrated by bilateral oophorectomy to build estrogen deprivation in vitro and in vivo experimental models, respectively. (1) In vitro experiments:according to different treatments the estrogen deprived ectopic endometrial cells were classified into 4 groups: a. EGF group:the ectopic endometrial cells were cultured for 72 hours with different concentrations of EGF (0.01, 0.1, 1, 10, 50, 100 ng/ml), the results of EGF group were represented by the result of cells treated by 10 ng/ml EGF cultured for 72 hours; b. EGF+PD98059 group:the ectopic endometrial cells were cultured for 72 hours with 5×10(-2) mol/L PD98059 (inhibitor of ERK), followed by a cultivation for 72 hours treated by 10 ng/ml EGF+5×10(-2) mol/L PD98059; c. EGF+ ICI182780 group: the ectopic endometrial cells were cultured for 72 hours with 10(-6) mol/L ICI182780 [inhibitor of estrogen receptor(ER)], followed by a cultivation for 72 hours treated by 10 ng/ml EGF+10(-6) mol/L ICI182780; d. Blank control group:the ectopic endometrial cells were cultured with no treatment. The proliferation activity of ectopic endometrial cells in all groups after treatment were examined by methyl thiazolyl tetrazolium (MTT) method represented by absorbance value (A). The expression of p-ERK1/2 protein were detected by western blot. (2) In vivo experiments: 64 female nude mice were randomly divided into control and castration groups (both n=32) using random number chart. The mice in castration group were castrated by bilateral oophorectomy on 3 weeks after the endometriosis model was established. The levels of EGF, EGFR, p-ERK1/2 protein in ectopic lesions of both groups were measured on 4, 6, 8 and 10 weeks after the endometriosis model was established by western blot. RESULTS: (1) The proliferation activity of ectopic endometrial cells:the proliferation activity of ectopic endometrial cells treated by different concentrations of EGF (0.01, 0.1, 1, 10, 50, 100 ng/ml) for 72 hours were 0.310±0.010, 0.340±0.020, 0.670±0.010, 0.980±0.030, 1.360±0.020, 1.670±0.020, respectively, the proliferation activity was increased along with of EGF concentrations.The proliferation activity was 0.680±0.030 at EGF+ PD98059 group, the differences exhibited significant difference when compared with that at EGF group with 100 ng/ml for 72 hours (P<0.01) .The proliferation activity of EGF+ ICI182780 and blank control groups were 0.330±0.030 and 0.310±0.030, respectively, which did not reached statistical differences (P>0.05). (2) The expression of EGF, EGFR, pERK1/2 protein: a. In vitro experiments:the levels of p-ERK1/2 protein in EGF and blank control groups were 0.670±0.020 and 0.600±0.010, respectively, which reached statistical differences (P<0.05). The level of p-ERK1/2 protein in EGF+ PD98059 group was 0.610±0.020, which exhibited significant differences with that at blank control group (P>0.05). b. In vivo experiments:at 4, 6 and 8 weeks after the endometriosis models were established, the expression of EGF protein in the ectopic lesions of castration group and control group were (0.530±0.015 versus 0.610±0.015), (0.400±0.029 versus 0.620±0.018), (0.560±0.026 versus 0.630±0.021), respectively, the levels of EGFR protein were (0.500±0.030 versus 0.640±0.030), (0.470±0.020 versus 0.630±0.020), (0.510±0.030 versus 0.610±0.020) respectively, and the level of p-ERK1/2 protein were (0.500±0.020 versus 0.580±0.020), (0.490±0.020 versus 0.580±0.020), (0.570±0.020 versus 0.590±0.020), respectively. The difference of EGF, EGFR, p-ERK1/2 protein expression levels between two groups did not exhibited significant difference (P<0.01, P<0.01, P<0.05). At 10 weeks after the endometriosis models were established, the levels of EGF protein in castration group and control group were both 0.620±0.020, the levels of EGFR protein were both 0.610±0.020, and the level of p-ERK1/2 protein were 0.590±0.010 and 0.600±0.020. No statistical difference (P>0.05) was found between those two groups (P>0.05). CONCLUSIONS: EGF could stimulate the proliferation of ectopic endometrial cells by activating the ERK pathway under estrogen deprivation conditions. The inhibition of EGF signaling system in ectopic lesions was alleviated along with the prolongation of the period of estrogen deprivation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Endometriose/patologia , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Ovariectomia , Animais , Células Cultivadas , Modelos Animais de Doenças , Endometriose/metabolismo , Endométrio/metabolismo , Endométrio/patologia , Fator de Crescimento Epidérmico/administração & dosagem , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/farmacologia , Antagonistas de Estrogênios/administração & dosagem , Antagonistas de Estrogênios/farmacologia , Estrogênios/deficiência , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Flavonoides/administração & dosagem , Flavonoides/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Distribuição Aleatória , Transdução de Sinais
13.
PeerJ Comput Sci ; 9: e1400, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37346665

RESUMO

Visual Question Answering (VQA) is a significant cross-disciplinary issue in the fields of computer vision and natural language processing that requires a computer to output a natural language answer based on pictures and questions posed based on the pictures. This requires simultaneous processing of multimodal fusion of text features and visual features, and the key task that can ensure its success is the attention mechanism. Bringing in attention mechanisms makes it better to integrate text features and image features into a compact multi-modal representation. Therefore, it is necessary to clarify the development status of attention mechanism, understand the most advanced attention mechanism methods, and look forward to its future development direction. In this article, we first conduct a bibliometric analysis of the correlation through CiteSpace, then we find and reasonably speculate that the attention mechanism has great development potential in cross-modal retrieval. Secondly, we discuss the classification and application of existing attention mechanisms in VQA tasks, analysis their shortcomings, and summarize current improvement methods. Finally, through the continuous exploration of attention mechanisms, we believe that VQA will evolve in a smarter and more human direction.

14.
Zhonghua Fu Chan Ke Za Zhi ; 47(3): 205-11, 2012 Mar.
Artigo em Zh | MEDLINE | ID: mdl-22781073

RESUMO

OBJECTIVE: To evaluate the inhibitory effects on Candida albicans of vagina cells transferred with antimicrobial peptide LL-37 and human defensin 5 (HD5) recombinant plasmids and observe secretion of IL-8. METHODS: (1) The epithelial cells from female vagina were culture primarily. The pcDNA3.1(+)/HD5-EGFP and pcDNA3.1(+)/LL-37-EGFP eukaryotic recombinant plasmids were separately or jointly transferred into the fourth generation of vaginal epithelial cells. Two test groups were defined: one test group was no Candida albicans group including four subgroups which were untransferred group, HD5 group transferred with pcDNA3.1(+)/HD5-EGFP, LL-37 group transferred with pcDNA3.1(+)/LL-37-EGFP, combining transferring group transferred with pcDNA3.1(+)/HD5-EGFP and pcDNA3.1(+)/LL-37-EGFP; the other test group was with Candida albicans group which the Candida albicans were coincubated with the four subgroups described above. (2) For examination of cytokines and chemokines, at 6, 12, 24 and 48 hours, the supernatant of every group was collected. ELISA was applied to detect the levels of LL-37, HD5 and IL-8. At each time point, the growth inhibition of Candida albicans was calculated by glucose consumption testing. RESULTS: (1) The max level of LL-37, HD5 and IL-8 reached max level after being transferred for 24 hours, then showed decreasing trend. The secretion of LL-37, HD5 and IL-8 was significant higher in combining transferring group in Candida albicans group than other groups, and the secretion level of LL-37, HD5 and IL-8 was (100.16 ± 0.81) ng/ml, (58.50 ± 2.08) µg/ml and (101.03 ± 1.59) pg/ml (P < 0.01). (2) In different time point, the absorbance of each subgroup without Candida albicans declined slowly, and there were no statistically significant difference (P > 0.05), as while as in LL-37 subgroup and HD5 subgroup with Candida albicans. In group with Candida albicans, the absorbance of combining transferring subgroup were 3.210 ± 0.010, 3.150 ± 0.030, 3.099 ± 0.030 and 2.970 ± 0.040 at 6, 12, 24 and 48 hours, respectively, which was significantly higher than those in the other cells (P < 0.01), and the declined trend was the slowest. CONCLUSIONS: The antifungal ability of vaginal epithelial cell became stronger after being transferred with LL-37 and HD5 recombinant plasmids. LL-37 and HD5 could also possess immunomodulatory activity and induce chemokine IL-8 production.


Assuntos
Candida albicans/crescimento & desenvolvimento , Catelicidinas/genética , Células Epiteliais/metabolismo , Vagina/citologia , alfa-Defensinas/genética , Peptídeos Catiônicos Antimicrobianos , Candida albicans/efeitos dos fármacos , Catelicidinas/metabolismo , Catelicidinas/farmacologia , Células Cultivadas , Técnicas de Cocultura , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Feminino , Humanos , Interleucina-8/metabolismo , Plasmídeos/genética , Transfecção , alfa-Defensinas/metabolismo , alfa-Defensinas/farmacologia
15.
PeerJ Comput Sci ; 8: e908, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35494798

RESUMO

The whole sentence representation reasoning process simultaneously comprises a sentence representation module and a semantic reasoning module. This paper combines the multi-layer semantic representation network with the deep fusion matching network to solve the limitations of only considering a sentence representation module or a reasoning model. It proposes a joint optimization method based on multi-layer semantics called the Semantic Fusion Deep Matching Network (SCF-DMN) to explore the influence of sentence representation and reasoning models on reasoning performance. Experiments on text entailment recognition tasks show that the joint optimization representation reasoning method performs better than the existing methods. The sentence representation optimization module and the improved optimization reasoning model can promote reasoning performance when used individually. However, the optimization of the reasoning model has a more significant impact on the final reasoning results. Furthermore, after comparing each module's performance, there is a mutual constraint between the sentence representation module and the reasoning model. This condition restricts overall performance, resulting in no linear superposition of reasoning performance. Overall, by comparing the proposed methods with other existed methods that are tested using the same database, the proposed method solves the lack of in-depth interactive information and interpretability in the model design which would be inspirational for future improving and studying of natural language reasoning.

16.
Front Neurorobot ; 16: 877069, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35599666

RESUMO

In order to make the teleoperation system more practical, it is necessary to effectively control the tracking error convergence time of the teleoperation system. By combining the terminal sliding mode control method with the neural network adaptive control method, a bilateral continuous finite time adaptive terminal sliding mode control method is designed for the combined teleoperation system. The Lyapunov theory is used to analyze the stability of the closed-loop system, and the position tracking error is able to effectively converge in time. Finally, the effectiveness of the proposed control scheme is verified by MATLAB Simulink numerical simulation, and the numerical analysis of the results shows that the method has better system performance. Compared with the traditional two-sided control method (TPDC) of PD time-delay teleoperation system, the control method in this paper has good performance, improves stability, and makes steady-state errors smaller and better tracking.

17.
Front Neurorobot ; 16: 840594, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35242022

RESUMO

Endoscopic imaging plays a very important role in the diagnosis and treatment of lesions. However, the imaging range of endoscopes is small, which may affect the doctors' judgment on the scope and details of lesions. Image mosaic technology can solve the problem well. In this paper, an improved feature-point pair purification algorithm based on SIFT (Scale invariant feature transform) is proposed. Firstly, the K-nearest neighbor-based feature point matching algorithm is used for rough matching. Then RANSAC (Random Sample Consensus) method is used for robustness tests to eliminate mismatched point pairs. The mismatching rate is greatly reduced by combining the two methods. Then, the image transformation matrix is estimated, and the image is determined. The seamless mosaic of endoscopic images is completed by matching the relationship. Finally, the proposed algorithm is verified by real endoscopic image and has a good effect.

18.
Front Neurorobot ; 16: 928863, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937561

RESUMO

A bilateral adaptive control method based on PEB control structure is designed for a class of time-delay force feedback teleoperation system without external interference and internal friction to study the uncertainty of dynamic parameters and time delay. The stability and tracking performances of the closed-loop constant time delay teleoperation system are analyzed by Lyapunov stability theory. Finally, the controller designed in this paper is successfully applied to the teleoperation system composed of a two-degree of freedom rotating manipulator as the master robot and the slave robot. The simulation is carried out in no operator and environment force or with operator and environment force. The adaptive bilateral control method's control performance is compared with that of the traditional time-delay teleoperation system. Finally, it is verified that the method has good control performance.

19.
Front Oncol ; 12: 832037, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35574417

RESUMO

Cone-beam Computerized Tomography (CBCT) has the advantages of high ray utilization and detection efficiency, short scan time, high spatial and isotropic resolution. However, the X-rays emitted by CBCT examination are harmful to the human body, so reducing the radiation dose without damaging the reconstruction quality is the key to the reconstruction of CBCT. In this paper, we propose a sparse angle CBCT reconstruction algorithm based on Guided Image FilteringGIF, which combines the classic Simultaneous Algebra Reconstruction Technique(SART) and the Total p-Variation (TpV) minimization. Due to the good edge-preserving ability of SART and noise suppression ability of TpV minimization, the proposed method can suppress noise and artifacts while preserving edge and texture information in reconstructed images. Experimental results based on simulated and real-measured CBCT datasets show the advantages of the proposed method.

20.
Sheng Li Xue Bao ; 63(3): 267-71, 2011 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-21681346

RESUMO

The present study aims to investigate the effects of soluble endoglin (sEng) on invasive ability of cultured cytotrophoblasts of first trimester of pregnancy. Cytotrophoblasts of normal 6 to 8-week pregnancy were cultured by trypsin digestion method, and were incubated with cell culture medium without (control group) and with 10 µg/L sEng (sEng group), respectively for 24 h. The invasive ability was determined by transwell invasion assay, and expressions of MMP-2, MMP-9 mRNA and protein were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot, respectively. The results showed that the invasive ability of cytotrophoblasts in sEng group was lower than that in control group (P < 0.05). Compared with control group, the expressions of MMP-2 and MMP-9 mRNA and protein of cytotrophoblasts were significantly lower (P < 0.05). In conclusion, sEng may participate in the genesis of preeclampsia by affecting the invasive ability of cytotrophoblasts through regulation of the expression of MMP-2 and MMP-9.


Assuntos
Antígenos CD/farmacologia , Movimento Celular/efeitos dos fármacos , Placentação/fisiologia , Trofoblastos/citologia , Movimento Celular/fisiologia , Células Cultivadas , Endoglina , Feminino , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Pré-Eclâmpsia/fisiopatologia , Gravidez , Primeiro Trimestre da Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Superfície Celular
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