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1.
Polymers (Basel) ; 15(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37242905

RESUMO

To solve the issue of the poor temperature stability of conventional modified asphalt, polyurethane (PU) was used as a modifier with its corresponding curing agent (CA) to prepare thermosetting PU asphalt. First, the modifying effects of the different types of PU modifiers were evaluated, and the optimal PU modifier was then selected. Second, a three-factor and three-level L9 (33) orthogonal experiment table was designed based on the preparation technology, PU dosage, and CA dosage to prepare the thermosetting PU asphalt and asphalt mixture. Further, the effect of PU dosage, CA dosage, and preparation technology on the 3d, 5d, and 7d splitting tensile strength, freeze-thaw splitting strength, and tensile strength ratio (TSR) of the PU asphalt mixture was analyzed, and a PU-modified asphalt preparation plan was recommended. Finally, a tension test was conducted on the PU-modified asphalt and a split tensile test was performed on the PU asphalt mixture to analyze their mechanical properties. The results show that the content of PU has a significant effect on the splitting tensile strength of PU asphalt mixtures. When the content of the PU modifier is 56.64% and the content of CA is 3.58%, the performance of the PU-modified asphalt and mixture is better when prepared by the prefabricated method. The PU-modified asphalt and mixture have high strength and plastic deformation ability. The modified asphalt mixture has excellent tensile performance, low-temperature performance, and water stability, which meets the requirements of epoxy asphalt and the mixture standards.

2.
Nanomedicine (Lond) ; 18(8): 667-678, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37199307

RESUMO

Aim: To achieve accurate detection of circulating tumor cells (CTCs) in a large-volume sample. Materials & methods: Silica nanoparticles were crosslinked layer-by-layer on glass slides as the substrate of a chip using polyacrylic acid. Polyacrylic acid was immobilized as a spacer and capture ligands were immobilized on the spacer. Results: The chip can be integrally applied to capture, post-treatment and imaging detection for CTCs. The detected cell numbers were 33 and 40 for 9 cell/ml samples and clinical blood samples (7.5 ml), respectively. The detection ratio of positive samples was 100%. Conclusion: The significantly increased detected number for CTCs indicates that this methodology may avoid or greatly reduce the false-negative ratio of positive clinical samples.


Assuntos
Nanopartículas , Células Neoplásicas Circulantes , Humanos , Linhagem Celular Tumoral , Diagnóstico por Imagem , Separação Celular
3.
Polymers (Basel) ; 15(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36679296

RESUMO

Finite element numerical simulation calculation of pavement structure load response is widely applied; however, there is still a lack of research on the polyurethane (PU) mixture composite pavement load response. The mechanical characteristics of PU mixture composite pavement are not well understood, and there is a lack of research on typical pavement structures of PU mixtures, which limits their application in pavement structures. Therefore, herein, the mechanical properties of PU mixtures are analysed using the dynamic modulus test, uniaxial penetration test, and fatigue test. Further, the finite element theory calculation method is used to realize the load response calculation of orthogonal design composite pavement structure. The results show that PU mixtures exhibit more obvious elastic characteristics and have good shear resistance, fatigue stability, and temperature stability, and can be used as shear and anti-fatigue layers. The structure of '4 cm SMA-13 + 5 cm PUM-20 + 6 cm PUM-25 + semi-rigid base' is recommended for the PU mixture composite structure. In comparison to typical asphalt pavement, the analysis shows that except for shear stress, temperature has little effect on the load response of PU composite pavement structures, while high temperatures lead to a significant increase in the load response of typical asphalt pavement structures. The PU composite pavement can bear greater loads and has a reduced thickness of its surface layer by about 3 cm in comparison to conventional pavement. The results of this study provide theoretical support for the design of PU mixture pavement structures and promote the popularization and application of PU mixture pavement.

4.
Polymers (Basel) ; 14(13)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35808761

RESUMO

In order to produce a high-viscosity asphalt and mixtures that can be used for ultra-thin overlays, high contents of Styrene-butadiene-styrene (SBS, 5%, 6%, 7%), styrene butadiene rubber (SBR, 1%, 2%, 3%) and micro carbon fiber (MCF, 0.8%) were used to modify conventional asphalt to prepare high-viscosity modified asphalt suitable for this purpose. The performance of the modified asphalts was evaluated by conventional index, kinematic viscosity, dynamic shear rheological test (DSR), multiple stress creep recovery test (MSCR), and bending beam rheometer test (BBR). The road performance of the modified asphalt mixtures was evaluated by high-temperature rutting, low-temperature bending, freeze-thaw splitting, fatigue, speckle, anti-skid, and water seepage tests. The results show that increasing the content of SBS can improve the high-temperature deformation resistance, low-temperature failure strain, kinematic viscosity, and viscosity toughness of modified asphalt, and the optimum content of SBS was 6%. SBR can improve the high-temperature performance, kinematic viscosity, and water damage resistance of modified asphalt, and the optimum dosage was 2%. Compared with 5% SBS-modified asphalt mixture, the dynamic stability, low-temperature failure strain, and freeze-thaw splitting strength ratio of 6% SBS + 0.8% MCF composite-modified asphalt mixture were increased by 48.7%, 24.7%, and 5.2% respectively. Compared with the 5% SBS-modified asphalt, the same characteristics of the 2% SBR + 5% SBS + 0.8% MCF composite-modified asphalt increased by 127.1%, 13.5%, and 5.5%, respectively. Compared with 5% SBS-modified asphalt, the fatigue performance of 6% SBS + 0.8% MCF-modified asphalt was improved by 32.2%. The kinematic viscosity of 6% SBS + 0.8% MCF and 5% SBS + 0.8% MCF + 2% SBR modified asphalt met the performance requirements of high-viscosity asphalt and had excellent road performance. It can be applied to ultra-thin overlays to optimize its adhesion with the original pavement.

5.
Int J Ophthalmol ; 14(4): 589-599, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33875953

RESUMO

AIM: To evaluate the global trends in and explore hotspots of high myopia (HM) research. METHODS: This bibliometric analysis was used to reveal the publication trends in HM research field based on the Web of Science Core Collection (WoSCC). VOSviewer version 1.6.13 software was used to analyze the data and construct a knowledge map including the yearly publication number, journals, countries, international collaborations, authors, research hotspots, and intellectual base in HM. RESULTS: The search engine found 3544 peer-reviewed publications on HM between 2010 and 2019, and the yearly research output substantially elevated over the past decade. China is the top publishing country, and Sun Yat-sen University was the most active academic institution. Jonas JB is the top publishing scientist, and Investigative Ophthalmology and Visual Science (IOVS) was the most productive journal. The highest cited references mainly focused on epidemiology and management. The keywords formed 6 clusters: 1) refractive surgery; 2) etiology and clinical characteristics; 3) the mechanism of eye growth; 4) management for myopic maculopathy; 5) vitrectomy surgical treatment; 6) myopia-associated glaucoma-like optic neuropathy. CONCLUSION: The evaluation of development trends based on the data extracted from WoSCC can provide valuable information and guidance for ophthalmologists and public health researchers to improve management procedures in HM field.

6.
Clin Genitourin Cancer ; 17(6): e1129-e1136, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31594735

RESUMO

BACKGROUND: The optimal points for halting and resuming treatment in intermittent androgen deprivation therapy (IADT) for metastatic prostate cancer patients are controversial. PATIENTS AND METHODS: In the 65 metastatic prostate cancer patients in group 1, androgen deprivation therapy was stopped when prostate-specific antigen (PSA) levels reached a nadir and was resumed when PSA levels doubled and ≥ 1.0 ng/mL (new protocol). In the 62 patients in group 2, androgen deprivation therapy was stopped 3 months after PSA = 0.2 ng/mL and resumed at PSA ≥ 4.0 ng/mL (Chinese Urological Association guideline). The total IADT duration, overall on-treatment and off-treatment time, tumor clinical progression ratio, performance status improvement, and treatment-related adverse effects were retrospectively analyzed. RESULTS: In groups 1 and 2, the median total IADT durations were 51 and 46.5 months (significant difference, P = .006), median overall on-treatment times were 28 and 27.5 months (no significant difference, P > .05), and median overall off-treatment times were 23 and 19 months (significant difference, P < .001), respectively. Multivariate Cox regression analysis indicated that patients in group 1 had significantly higher progression-free-survival (hazard ratio, 0.634; P = .014). Two cases of clinical progression occurred group 1 and 5 in group 2; there was no significant difference (P > .05). There were no significant differences between the groups in terms of performance status improvement and treatment-related adverse effects. CONCLUSION: The new protocol was found to be beneficial, showing less biochemical/clinical progression, satisfactory performance status, and acceptable treatment-related adverse effects.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/tratamento farmacológico , Idoso , Antagonistas de Androgênios/efeitos adversos , Progressão da Doença , Humanos , Masculino , Metástase Neoplásica , Neoplasias da Próstata/metabolismo , Análise de Regressão , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
7.
Zhonghua Nan Ke Xue ; 25(11): 971-977, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-32233229

RESUMO

OBJECTIVE: To investigate the dynamic change in the gene expression profile of the rat BPH tissue with progressive atrophy after complete denervation. METHODS: Twelve 29-week-old male rats with spontaneous hypertension and spontaneously developed BPH were used for this study, of which 3 were included in the control (C) group and the other 9 underwent complete denervation of the prostate. At 3, 7 and 11 days after operation (the D3, D7 and D11 groups), all the rats were sacrificed and their ventral prostatic lobes harvested for histopathological examination and RNA extraction, and the RNA samples were subjected to whole genome microarray of the expression profile, followed by real-time RT-PCR validation and bioinformatics analysis. RESULTS: Progressive atrophy of the BPH tissue was observed in the rats after complete denervation. Whole genome microarray of the expression profile was successfully performed for all the samples, and its reliability validated by real-time RT-PCR of 6 differentially expressed genes selected randomly. Hierarchical clustering analysis showed 108 up-regulated and 175 down-regulated genes in the differentially expressed ones between the D3 and C groups, 462 up-regulated and 189 down-regulated in those between the D7 and C groups, and 548 up-regulated and 256 down-regulated in those between the D11 and C groups. GO functional enrichment analysis indicated that the genes in each differentially expressed gene set participated in hundreds of molecular functions, biological processes and cellular components, while pathway enrichment analysis showed their involvement in hundreds of signaling pathways, of which many were enriched simultaneously in each differentially expressed gene set and ranked as the most enriched ones, and most of the genes involved were up-regulated and related with the activation of the complement system. CONCLUSIONS: Large numbers of abnormally expressed genes are involved in the progressive atrophy of rat BPH tissue after complete denervation, and these genes participate in hundreds of molecular functions, biological progresses, cellular components and signaling pathways. Abnormal activation of the complement system may play an important role in the progressive atrophy of the BPH tissue.


Assuntos
Denervação , Próstata/inervação , Hiperplasia Prostática/genética , Hiperplasia Prostática/cirurgia , Transcriptoma , Animais , Proteínas do Sistema Complemento/genética , Perfilação da Expressão Gênica , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Reprodutibilidade dos Testes
8.
Chin Med J (Engl) ; 129(24): 2899-2906, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27958220

RESUMO

BACKGROUND: The medium-to-long-term use of antimuscarinics alone or in combination with an α-blocker in men with an enlarged prostate is still controversial. This double-blind, placebo-controlled, randomized clinical trial aimed to investigate the efficacy and safety of medium-to-long-term use of tolterodine extended release (ER) with or without tamsulosin in patients with benign prostate hyperplasia (BPH) and larger prostate size. METHODS: Totally, 152 patients (age ≥50 years) with BPH, International Prostate Symptom Score (IPSS) ≥12, quality-of-life (QoL) score ≥3, and total prostate volume ≥25 ml were enrolled in this study. The patients were randomized into four groups (n = 38 in each) to receive tolterodine ER placebo plus tamsulosin placebo, 0.2 mg tamsulosin plus tolterodine ER placebo, 4 mg tolterodine ER plus tamsulosin placebo, or tolterodine ER plus tamsulosin once daily for 24 weeks. IPSS (total, storage, and voiding subscales), QoL, maximum urinary flow rate (Qmax), and postvoid residual volume (PVR) were collected at baseline, and at weeks 4, 12, and 24. RESULTS: Compared with placebo, tolterodine ER plus tamsulosin significantly improved total IPSS (-7.15, -12.20, and -14.66 vs. -3.51, -5.78, and -7.23), storage IPSS (-3.56, -5.63, and -6.66 vs. -1.52, -1.21, and -2.43), voiding IPSS (-2.88, -5.10, and -6.48 vs. -1.52, -3.03, and -2.97), QoL (-1.21, -2.40, and -3.21 vs. -0.39, -1.41, and -1.60), Qmax (2.21, 7.97, and 9.72 ml/s vs. 2.15, 2.44, and 2.73 ml/s), and PVR (-17.88, -26.97, and -27.89 ml vs. -12.03, -11.16, and -16.73 ml) at weeks 4, 12, and 24, respectively; the differences were all statistically significant (P < 0.05). Adverse events (AEs) were not increased with treatment progression. Tolterodine ER alone did not improve total IPSS (-4.61, -6.79, and -5.70), voiding IPSS (-0.64, -1.83, and -1.45), QoL (-0.69, -1.21, and -1.41), or Qmax(-0.79, 2.83, and 1.11 ml/s), compared with placebo (all P > 0.05). However, a gradual increase in PVR (10.03, 10.41, and 12.89 ml) and more urinary AEs suggestive of urinary retention (11/38 vs. 4/38) were observed. CONCLUSION: Medium-to-long-term use of tolterodine ER plus tamsulosin should be recommended in patients with BPH and an enlarged prostate volume. TRIAL REGISTRATION: www.chictr.org.cn, ChiCTR-TRC-09000596; http://www.chictr.org.cn/showproj.aspx?proj=8939.


Assuntos
Hiperplasia Prostática/tratamento farmacológico , Sulfonamidas/uso terapêutico , Tartarato de Tolterodina/uso terapêutico , Antagonistas Adrenérgicos alfa/administração & dosagem , Antagonistas Adrenérgicos alfa/uso terapêutico , Idoso , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/efeitos dos fármacos , Próstata/patologia , Qualidade de Vida , Sulfonamidas/administração & dosagem , Tansulosina , Tartarato de Tolterodina/administração & dosagem , Resultado do Tratamento
9.
Chin Med J (Engl) ; 126(9): 1647-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23652045

RESUMO

BACKGROUND: The effects of triterpenic acid from Prunella vulgaris L. (TAP) on diabetes and its mechanism are uncertain. The aim of this study was to investigate the effects of TAP on antihyperglycemic, antioxidant, and pancreas-protective in streptozotozin (STZ)-diabetic rats. METHODS: The diabetic model was produced by injection of 60 mg/kg STZ. Blood was drawn from the tail vein of rats after 72 hours. Rats with blood glucose ≥ 16.7 mmol/L were considered diabetic. Diabetic rats were randomly divided into four groups: (1) Diabetes rat (STZ), (2) Diabetic rats treated with 50 mg/kg of triterpenic acid from Prunella vulgaris L (STZ + TAP50), (3) Diabetic rats treated with 100 mg/kg TAP (STZ + TAP100), and (4) Diabetic rats treated with 200 mg/kg TAP (STZ + TAP200). Normal rats (n = 10) acted as the control group (NC). TAP was administered by the intragastric route once each day for six weeks. Body weight and the concentration of blood glucose (BG) were measured after three and six weeks. Fructosamine (FMN), malondialdehyde (MDA), and nitric oxide (NO), and the activities of nitric oxide synthase (NOS) and superoxide dismutase (SOD) in serum were determined after six weeks using commercially available kits following the manufacturer's instructions. Pathologic changes in pancreatic ß-cells were also investigated by microscopic examination after hematoxylin-eosin (HE) staining. The level of SOD mRNA in pancreatic ß-cells was measured by polymerase chain reaction (PCR). RESULTS: The levels of BG, FMN, NO, and MDA and the activities of NOS in serum in the four diabetes groups were significantly increased compared with the control group (P < 0.01). The activity of SOD in serum and the body weight was significantly decreased compared with the control group (P < 0.01). After administration of TAP to diabetic rats for six weeks, the body weight and the levels of BG, FMN, MDA, NO and the activity of NOS in serum decreased significantly compared with the STZ group in a dose-dependent manner. The activity of SOD in serum and body weight increased significantly compared with the STZ group in a dose-dependent manner. In addition, diabetic rats showed a significant decrease in SOD mRNA expression in pancreatic ß cells. However, these changes were reversed by TAP. Histopathological examination also showed the protective effect of TAP on pancreatic ß cells. CONCLUSIONS: Triterpenic acid from Prunella vulgaris L. has an anti-diabetic effect, by controlling blood glucose and antioxidants, and has a protective effect on the pancreas.


Assuntos
Glicemia/análise , Diabetes Mellitus Experimental/tratamento farmacológico , Células Secretoras de Insulina/efeitos dos fármacos , Prunella/química , Triterpenos/uso terapêutico , Animais , Diabetes Mellitus Experimental/metabolismo , Células Secretoras de Insulina/patologia , Masculino , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Estreptozocina , Superóxido Dismutase/genética
10.
Chinese Medical Journal ; (24): 1647-1653, 2013.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-350448

RESUMO

<p><b>BACKGROUND</b>The effects of triterpenic acid from Prunella vulgaris L. (TAP) on diabetes and its mechanism are uncertain. The aim of this study was to investigate the effects of TAP on antihyperglycemic, antioxidant, and pancreas-protective in streptozotozin (STZ)-diabetic rats.</p><p><b>METHODS</b>The diabetic model was produced by injection of 60 mg/kg STZ. Blood was drawn from the tail vein of rats after 72 hours. Rats with blood glucose ≥ 16.7 mmol/L were considered diabetic. Diabetic rats were randomly divided into four groups: (1) Diabetes rat (STZ), (2) Diabetic rats treated with 50 mg/kg of triterpenic acid from Prunella vulgaris L (STZ + TAP50), (3) Diabetic rats treated with 100 mg/kg TAP (STZ + TAP100), and (4) Diabetic rats treated with 200 mg/kg TAP (STZ + TAP200). Normal rats (n = 10) acted as the control group (NC). TAP was administered by the intragastric route once each day for six weeks. Body weight and the concentration of blood glucose (BG) were measured after three and six weeks. Fructosamine (FMN), malondialdehyde (MDA), and nitric oxide (NO), and the activities of nitric oxide synthase (NOS) and superoxide dismutase (SOD) in serum were determined after six weeks using commercially available kits following the manufacturer's instructions. Pathologic changes in pancreatic β-cells were also investigated by microscopic examination after hematoxylin-eosin (HE) staining. The level of SOD mRNA in pancreatic β-cells was measured by polymerase chain reaction (PCR).</p><p><b>RESULTS</b>The levels of BG, FMN, NO, and MDA and the activities of NOS in serum in the four diabetes groups were significantly increased compared with the control group (P < 0.01). The activity of SOD in serum and the body weight was significantly decreased compared with the control group (P < 0.01). After administration of TAP to diabetic rats for six weeks, the body weight and the levels of BG, FMN, MDA, NO and the activity of NOS in serum decreased significantly compared with the STZ group in a dose-dependent manner. The activity of SOD in serum and body weight increased significantly compared with the STZ group in a dose-dependent manner. In addition, diabetic rats showed a significant decrease in SOD mRNA expression in pancreatic β cells. However, these changes were reversed by TAP. Histopathological examination also showed the protective effect of TAP on pancreatic β cells.</p><p><b>CONCLUSIONS</b>Triterpenic acid from Prunella vulgaris L. has an anti-diabetic effect, by controlling blood glucose and antioxidants, and has a protective effect on the pancreas.</p>


Assuntos
Animais , Masculino , Ratos , Glicemia , Diabetes Mellitus Experimental , Tratamento Farmacológico , Metabolismo , Células Secretoras de Insulina , Patologia , Prunella , Química , RNA Mensageiro , Ratos Sprague-Dawley , Estreptozocina , Superóxido Dismutase , Genética , Triterpenos , Usos Terapêuticos
11.
Zhonghua Yi Xue Za Zhi ; 92(41): 2927-9, 2012 Nov 06.
Artigo em Chinês | MEDLINE | ID: mdl-23328243

RESUMO

OBJECTIVE: To summarize the surgical therapy and profiles of lower limb blood flow during surgery for chronic infrarenal aortic occlusion. METHODS: A total of 36 patients of chronic infrarenal aortic occlusion underwent surgical procedures at our department from 2004 to 2011. Their clinical data were analyzed. Several methods were applied at different time points during surgery to observe the lower limb blood flow. RESULTS: SaO2, waveforms of dorsalis pedis artery and posterior tibial artery changed dramatically at different time points during surgery. Before and after blood occlusion, the SaO2 was 82% ± 6% and 23% ± 4% respectively, 1min after unclamped and after abdomen-closing, the SaO2 increased to 66% ± 5% and 88% ± 8% respectively. CONCLUSION: Doppler blood flow and blood oxygen saturation monitors are simple, non-invasive and objective detection methods for lower limb blood flow. A combination of both methods can improve the safety of surgery. Keeping the limbs warm and uses of spasmolytic drugs can facilitate the recovery of postoperative blood flow of lower limbs.


Assuntos
Arteriopatias Oclusivas/cirurgia , Extremidade Inferior/irrigação sanguínea , Monitorização Intraoperatória , Adulto , Idoso , Aorta Abdominal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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