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1.
Heliyon ; 10(2): e24428, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293438

RESUMO

Al-Zn-Mg-Cu-Zr-Sc alloys with different Sc contents were fabricated by casting, deformation, and T6 treatment. Deformation methods including rolling and friction-stir processing (FSP) were used to design their grain structure. A low additive amount (0.1) of Sc cannot refine the grains of the alloy with rolling and T6 treatment, and it instead coarsened the grains. The reason was the non-uniform distribution of nanosize Al3(Sc,Zr) phases that led to the occurrence of abnormal grain growth during homogenization. Meanwhile, the alloy with only 0.1Sc exhibited finer grains after FSP and T6 treatment than the alloys subjected to the same process but with higher Sc additive amount. Alloys with rolling-induced elongated grain structure exhibited better mechanical properties, and alloys with FSP-induced fine equiaxed grain structure exhibited higher high-strain and high-temperature internal friction values. These features are important performance parameters for applications in fields where vibration and noise are sensitive. The optimum additive amounts of Sc for alloys with elongated and fine equiaxed grain structures were 0.25 and 0.1, respectively.

3.
Zhonghua Yi Xue Za Zhi ; 103(8): 566-571, 2023 Feb 28.
Artigo em Chinês | MEDLINE | ID: mdl-36822867

RESUMO

Objective: To explore the correlation between fluid load index and cardiovascular events in hemodialysis patients based on repeated body composition analyses. Methods: A prospective cohort study was conducted to collect the clinical data of patients undergoing maintenance hemodialysis (MHD) in the Department of Nephrology, Hangzhou Hospital of Traditional Chinese Medicine from July to September 2020. The pre-dialysis fluid overload (FO) index-overhydration (OH) was measured by bioelectrical impedance method, and the follow-up monitoring was conducted every 6 months. According to the baseline OH value, patients were divided into non-FO group (OH≤2.5 L) and FO group (OH>2.5 L). Moreover, according to the repeated measurements, the patients were divided into continuous non-FO group, continuous FO group and intermittent FO group. All patients were followed up until October 1, 2022, and the outcomes were recorded. The end point of follow-up was cardiovascular events. The cumulative incidence of cardiovascular events was calculated by the Kaplan-Meier method, and the risk factors of cardiovascular events were analyzed by Cox proportional hazards regression model. Results: A total of 289 patients were included, including 88 patients (30.4%) with FO and 201 patients (69.6%) with non-FO. There were 168 males (58.1%) and 121 (41.9%) females, with an average age of (58±13) years and an average follow-up time of (22.0±6.5) months. Kaplan-Meier analysis showed that the incidence of cardiovascular events in the baseline FO group was higher than that in the non-FO group (log-rank χ2=14.44, P<0.001). The incidence of cardiovascular events in both the continuous FO group and the intermittent FO group was higher than that in the continuous non-FO group (log-rank χ2=41.47, P<0.001; log-rank χ2=18.36, P<0.001). After adjustment for gender, age, comorbidities, and biochemical indicators, the incidence of cardiovascular events in the baseline FO group was 1.850 times of the non-FO group (95%CI: 1.046-3.271, P=0.034). The incidence of cardiovascular events in the continuous FO group was 4.679 times of the continuous non-FO group (95%CI: 2.189-10.002, P<0.001). The incidence of cardiovascular events in the intermittent FO group was 3.410 times of the continuous non-FO group (95%CI: 1.696-6.857, P=0.001). Conclusions: OH value measured by bioelectrical impedance can be used as an important reference index for clinical monitoring of cardiovascular events in MHD patients. Continuous chronic and intermittent exposures to FO are risk factors for cardiovascular events in hemodialysis patients.


Assuntos
Insuficiência Cardíaca , Desequilíbrio Hidroeletrolítico , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Diálise Renal/efeitos adversos , Fatores de Risco , Desequilíbrio Hidroeletrolítico/etiologia , Insuficiência Cardíaca/complicações , Composição Corporal
4.
Phys Rev Lett ; 127(15): 152702, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34678013

RESUMO

Fluorine is one of the most interesting elements in nuclear astrophysics, where the ^{19}F(p,α)^{16}O reaction is of crucial importance for Galactic ^{19}F abundances and CNO cycle loss in first generation Population III stars. As a day-one campaign at the Jinping Underground Nuclear Astrophysics experimental facility, we report direct measurements of the essential ^{19}F(p,αγ)^{16}O reaction channel. The γ-ray yields were measured over E_{c.m.}=72.4-344 keV, covering the Gamow window; our energy of 72.4 keV is unprecedentedly low, reported here for the first time. The experiment was performed under the extremely low cosmic-ray-induced background environment of the China JinPing Underground Laboratory, one of the deepest underground laboratories in the world. The present low-energy S factors deviate significantly from previous theoretical predictions, and the uncertainties are significantly reduced. The thermonuclear ^{19}F(p,αγ)^{16}O reaction rate has been determined directly at the relevant astrophysical energies.

6.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(3): 594-597, 2021 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-34145867

RESUMO

OBJECTIVE: To observe the movement of posterior teeth after losing the interproximal and occlusal contacts in adults from the amount and speed of mesial-distal, buccal-lingual, occlusal-gingival and three-dimensional movements. METHODS: Twenty cases of metal post-core restoration from the Department of Prosthodontics, Peking University School and Hospital of Stomatology were recruited into this study, which was an observational study. The restored teeth had complete mesial, distal, and occlusal contacts before treatment. All the interproximal and occlusal contacts were removed during the preparation for the post-core. The three-dimensional positions of the post-core preparation were obtained by the intraoral scanner at the day of tooth preparation and that of post-core placement. The amounts of mesial-distal, buccal-lingual and occlusal-gingival tooth movement were measured in the software. On this basis, the amount of three-dimensional tooth movement was calculated. The speed of tooth movement was calculated based on the elapsed time between the two scans. RESULTS: Ten females and ten males with an average age of (29.5±4.9) years were recruited. The average elapsed time was (10.9±2.7) days. The amount of the mesial-distal tooth movement was (134.8±61.2) µm, of the buccal-lingual tooth movement was (110.3±39.5) µm, of the occlusal-gingival tooth movement was (104.8±57.5) µm, and of the three-dimensional tooth movement was (211.4±71.0) µm, respectively. The amounts of mesial-distal, buccal-lingual and three-dimensional tooth movements were larger in female than in male (P < 0.05). The speed of the mesial-distal tooth movement was (13.1±7.8) µm/d, of the buccal-lingual tooth movement was (10.6±4.5) µm/d, of the occlusal-gingival tooth movement was (10.1±6.8) µm/d, and of the three-dimensional tooth movement was (20.5±9.7) µm/d, respectively. The speed of mesial-distal and buccal-lingual tooth movements were larger in female than in male (P < 0.05). The speed of three-dimensional tooth movement was slightly larger in female than in male, while there was no significant difference between different genders (P>0.05). CONCLUSION: The three-dimensional position of posterior teeth changed after losing the interproximal and occlusal contacts in adults. The female had more significant and faster tooth movement than the male.


Assuntos
Dente , Adulto , Feminino , Humanos , Masculino , Software , Técnicas de Movimentação Dentária , Adulto Jovem
7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 52(5): 948-951, 2020 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-33047735

RESUMO

OBJECTIVE: To assess the effects of loupes and microscope on the posture of prosthodontists when preparing the laminate veneer, and to assess the clinical value of loupes and microscope from the ergonomic aspects. METHODS: Twenty young prosthodontists from Department of Prosthodontics, Peking University School and Hospital of Stomatology were recruited into this study, which was a prospective, single blind, self-control trials. The research hypothesis was concealed and the participants were deceived about the precise purpose of the study to counterbalance the lack of direct blinding. The prosthodontists prepared laminate veneers of open window type in the artificial dental model, under routine visual field (control group), 2.5× headwear loupes (loupes group), and 8× operating microscope (microscopic group) by turning. The participants were photographed from profile view and front view. Thereafter, the subjective assessment was performed by themselves using the visual analogue score (VAS). The expert assessment was performed by two professors using modified-dental operator posture assessment instrument on the basis of photographs of the profile view and front view. RESULTS: The subjective assessment scores for the control group, loupes group and microscopic group were 4.55±1.96, 7.90±1.12, and 9.00±0.92, respectively. There was significant difference between the three groups' subjective scores (P < 0.05). The expert assessment scores for the control group, loupes group and microscopic group were 16.38±1.52, 15.15±1.30, and 13.60±0.88, respectively. There was significant difference between the three groups' expert assessment scores (P < 0.05). Specifically, the three groups' expert assessment scores were significantly different (P < 0.05) in trunk position (front to back) (1.33±0.41, 1.03±0.11, 1.00±0.00), head and neck position (front to back) (2.75±0.38, 2.13±0.36, 1.23±0.38), elbows level (1.38±0.43, 1.40±0.45, 1.13±0.22), and shoulders level (1.43±0.41, 1.23±0.34, 1.13±0.28). Thereinto, the microscopic group was better than loupes group in head and neck position (front to back) and elbows level (P < 0.05). CONCLUSION: Loupes and microscope improve the posture of the prosthodontist when preparing the laminate veneer, in which the microscope is better than loupes. Therefore, the magnification devices have clinical value from the ergonomic aspects.


Assuntos
Ergonomia , Postura , Odontólogos , Humanos , Estudos Prospectivos , Método Simples-Cego
11.
Zhonghua Xue Ye Xue Za Zhi ; 41(1): 23-27, 2020 Jan 14.
Artigo em Chinês | MEDLINE | ID: mdl-32023750

RESUMO

Objective: To evaluate possible effects of Gelctin-9 on acute graft versus host disease (aGVHD) development and clinical outcomes in patients before and afer allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: Peripheral blood samples were obtained from 29 patients and 15 healthy volunteers with heparin anticoagulant tubes. Samples were analyzed using ELISA kits to measure the serum concentrations of Galectin-9. Results: Patients developing aGVHD had significantly lower level of Galectin-9 [ (7.96±1.18) µg/L] before allo-HSCT compared with those not developing aGVHD [ (12.37±0.97) µg/L, P<0.001]. And after allo-HSCT, the consentration of Galectin-9 increased markedly in patients developing aGVHD [ (17.78±1.78) µg/L] compared with those not developing aGVHD [ (9.45±0.80) µg/L, P<0.001]. Patients developing 3-4 grade aGVHD had significantly higher level of Galectin-9 [ (23.25±2.59) µg/L] compared with those developing 1-2 grade aGVHD [ (14.37±1.45) µg/L, P=0.008] and those without aGVHD [ (9.45±0.80) µg/L, P<0.001]. The patients with lower level of Galectin-9 after allo-HSCT (<13.61 µg/L) showed more favorable clinical outcomes compared with those with higher level of Galectin-9 (≥13.61 µg/L) . The 3-year overall survival rates were (100.00±6.05) % and (69.23±12.80) %, respectively (P=0.009) . The cumulative incidence of non-relapse mortality was significantly higher in high Galectin-9 group [ (23.08±11.69) %] in comparison with low Gaelctin-9 group [ (0.00±7.39) %] (P=0.023) . There was no significant difference between the two groups in terms of the cumulative incidence of relapse. The cumulative incidence of relapse at 3 years were (8.33±7.98) % and (12.50±8.27) % in high and low Galectin-9 groups, respectively (P=0.708) . Conclusions: The serum concentration of Galectin-9 at the time of engraftment after allo-HSCT may be used as a predictor for the development and severity of aGVHD. Galectin-9 might be considered as a potential new approach to regulate transplant rejection to achieve desirable survival.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Galectinas , Humanos , Incidência , Taxa de Sobrevida , Transplante Homólogo
13.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(2): 390-395, 2020 Dec 30.
Artigo em Chinês | MEDLINE | ID: mdl-33879916

RESUMO

OBJECTIVE: To investigate the blood pressure and heart rate changes and influencing factors during single dental implant surgery. METHODS: A retrospective cohort study was conducted. Six hundred and forty cases underwent single dental implant placement in Department of Prosthodontics, Peking University School and Hospital of Stomatology from January 2016 to December 2016 were recruited in this study according to the inclusion and exclusion criteria. They were divided into different groups according to the exposure factors which were patient characteristics (gender, age) and surgical procedures (immediate placement, flap elevation, bone grafting). The correlation between blood pressure and heart rate variability during single dental implant surgery and the patient characteristics and surgical procedures were analyzed. RESULTS: The average systolic blood pressure variability was 9.47%±6.45% (maximum 46.04%), the average diastolic blood pressure variability was 12.18%±9.39% (maximum 88.00%), and the average heart rate variability was 10.59%±7.68% (maximum 49.12%). The effects of age and bone grafting on blood pressure variability, and of gender and immediate placement on heart rate variability, were statistically significant (P < 0.05), respectively. The incidence of abnormal intraoperative blood pressure rise was 4.69%, of which there were 4 cases (0.63%) of systolic blood pressure ≥180 mmHg and/or diastolic blood pressure ≥110 mmHg. The incidence of abnormal intraoperative heart rate rise was 6.72%. Hierarchical analysis showed a higher risk of abnormal intraoperative blood pressure rise in the elderly (≥60 years) male patients [P < 0.05, RR=3.409 (95%CI: 1.155-10.062) ] and flap elevation with bone grafting cases [P < 0.05, RR=2.382 (95%CI: 1.126-5.040)], respectively. There was no statistically significant association between abnormal heart rate rise and patient characteristics or surgical procedures (P>0.05). CONCLUSION: There was a certain risk of blood pressure and heart rate variability during dental implant surgery. Elderly male patients and flap elevation with bone grafting were risk factors of abnormal intraoperative blood pressure rise.


Assuntos
Implantes Dentários , Idoso , Pressão Sanguínea , Implantação Dentária Endóssea , Frequência Cardíaca , Humanos , Masculino , Maxila/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
15.
Eur Rev Med Pharmacol Sci ; 23(17): 7369-7374, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31539123

RESUMO

OBJECTIVE: The long noncoding RNA HOXC13 antisense RNA (HOXC13-AS) was overexpressed in several tumor specimens, and its overexpression was correlated with cells metastasis of tumors. However, its effects in other tumors remained largely unclear. In this work, we aimed to identify whether HOXC13-AS was abnormally expressed in hepatocellular carcinoma (HCC) and further explore its prognostic value. PATIENTS AND METHODS: QRT-PCR was applied for the examination of HOXC13-AS levels in 197 paired HCC specimens and matched non-tumor specimens. Chi-square tests were carried out for the verification of the relations between the levels of HOXC13-AS and the clinicopathologic features of HCC patients. The Kaplan-Meier methods were applied for the exploration of the prognostic value of HOXC13-AS. Multivariate analysis was performed using the Cox proportional hazard assays. RESULTS: Up-regulation of HOXC13-AS was observed in HCC tissues compared to matched normal tissues (p < 0.01). Higher levels of HOXC13-AS were associated with TNM stage (p = 0.024) and lymph node metastasis (p = 0.043). Survival assays showed that HCC patients with high-HOXC13-AS expressions had significantly shorter overall survival (p < 0.0106) and disease-free survival (p < 0.0066) compared to their counterparts with low-HOXC13-AS expressions. Multivariate analyses suggested HOXC13-AS as an independent prognostic factor for HCC patients. CONCLUSIONS: We showed that HOXC13-AS might serve as a promising biomarker for prognosis prediction of HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , RNA Longo não Codificante/genética , Regulação para Cima , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/genética , Metástase Linfática , Masculino , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico , Análise de Sobrevida
16.
Zhonghua Shao Shang Za Zhi ; 35(8): 628-629, 2019 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-31474050

RESUMO

In the process of establishing Sprague Dawley rat skin grafting model, to prevent rats from biting and scratching the wounds is the key factor for determining success or failure. To solve this problem, the author designed a restraint material, which consists of neck film ring and limb dressing. It plays a good role in preventing rats from biting and scratching the wounds, and is worthy of popularization and application.


Assuntos
Bandagens , Imobilização/instrumentação , Transplante de Pele , Animais , Modelos Animais de Doenças , Ratos , Ratos Sprague-Dawley
19.
Eur Rev Med Pharmacol Sci ; 22(22): 7710-7715, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30536314

RESUMO

OBJECTIVE: Long noncoding RNAs (lncRNAs) have recently emerged as important regulators in governing fundamental biological processes, as well as in tumorigenesis. LncRNA LINC01510 (LINC01510) was recently shown to be involved in colorectal cancer (CRC); however, its role in CRC remains unknown. The objective of this study was to evaluate LINC01510 expression and its relevance to the prognosis of CRC. PATIENTS AND METHODS: LINC01510 expression was detected in CRC tissues and cell lines by using quantitative real-time PCR (qRT-PCR). The correction between LINC01510 expression and clinical characteristics was evaluated with x2-test. Survival curves and log-rank test were used to analyze patients' survival. A Cox proportional hazard model was constructed to evaluate the association of LINC01510 expression with overall survival and disease-free survival, respectively. RESULTS: Here, we found that the levels of LINC01510 in CRC tissues were significantly higher than those in matched tumor-adjacent tissues. Moreover, high LINC01510 expression was observed to be closely correlated with histology/differentiation (p = 0.001), depth of invasion (p = 0.004) and TNM stage (p = 0.003). From the Kaplan-Meier survival curves, it was observed that patients with high expression of LINC01510 had shorter overall survival (p = 0.004) and disease-free survival (p = 0.000) as compared with the LINC01510-low group. In the multivariate analysis, high LINC01510 expression was an independent prognostic factor for both overall survival (p = 0.001) and disease-free survival (p = 0.001). CONCLUSIONS: We demonstrated that low LINC01510 expression was associated with the progression of CRC and could serve as a potential independent prognostic biomarker for patients with CRC.


Assuntos
Carcinogênese/genética , Neoplasias Colorretais/genética , RNA Longo não Codificante/genética , Progressão da Doença , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais
20.
Beijing Da Xue Xue Bao Yi Xue Ban ; 50(1): 53-57, 2018 Feb 18.
Artigo em Chinês | MEDLINE | ID: mdl-29483722

RESUMO

OBJECTIVE: To evaluate the effects of different surface treatments on the shear bond strength between zirconia and resin cement. METHODS: Forty zirconia discs were randomly divided into four groups (10 discs in each group) for different surface treatments: control, no surface treatment; sandblast, applied air abrasion with aluminum oxide particles; ultraviolet (UV), the zirconia sample was placed in the UV sterilizer at the bottom of the UV lamp at 10 mm, and irradiated for 48 h; cold plasma, the discs were put in the cold plasma cabinet with the cold plasma generated from the gas of He for 30 s. Specimens of all the groups were surface treated prior to cementation with Panavia F 2.0 cement. The surface morphology and contact angle of water were measured. The shear bond strengths were tested and the failure modes were examined with a stereomicroscope. RESULTS: Surface morphology showed no difference between the UV/cold plasma group and the control group. Sandblasted zirconia displayed an overall heterogeneous distribution of micropores. The contact angle of the control group was 64.1°±2.0°. After sandblasting, UV irradiation and cold plasma exposure, the values significantly decreased to 48.8°±2.6°, 27.1°±3.6° and 32.0°±3.3°. The values of shear bond strength of the specimens with sandblasted (14.82±2.01) MPa were higher than those with no treatment (9.41±1.07) MPa with statistically significant difference (P<0.05). The values of shear bond strength of the specimens with UV irradiation (10.02±0.64) MPa were higher than those with no treatment (9.41±1.07) MPa, but without statistically significant difference (P>0.05). The values of cold plasma group (18.34±3.05) MPa were significantly higher than those of control group (9.41±1.07) MPa, even more than those with sandblast(14.82±2.01) MPa (P<0.05). X-ray photoelectron spectroscopy (XPS) showed increase in oxygen (O) and decrease in carbon (C) elements after UV and cold plasma treatment. The surface C/O ratio also decreased after UV and cold plasma treatment. CONCLUSION: Zirconia specimens treated with UV and cold plasma could significantly improve the hydrophilicity. The surface morphology was unaffected by the UV irradiation and cold plasma treatments. The improvements of ziconia shear bond strength were slight in UV group without statistically significant difference. Cold plasma treatment significantly improved the shear bond strength between zirconia and resin cement.


Assuntos
Colagem Dentária , Cimentos de Resina , Teste de Materiais , Microscopia Eletrônica de Varredura , Distribuição Aleatória , Resistência ao Cisalhamento , Propriedades de Superfície , Zircônio
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