The recovery force of Ti-Nb coated and uncoated TiNi shape memory alloy rods was investigated. The rods were 6.0 mm, 6.5 mm and 7.0 mm in diameter respectively. The mean transition temperature was 33.0 degrees C. The rods were stored at -18 degrees C and pre-bent with a three-point bending fixture, the span was 20. 0 centimeters and the deflections were 5.0 mm, 10.0 mm, 15.0 mm and 20.0 mm, respectively. The rods were then heated in a constant temperature saline solution chamber. The experimental temperature was 37.0 C and 50.0 C respectively. The recovery force was measured in a constant displacement mode on biomaterial test machine. The results showed that the recovery force of the memory alloy rod increased with increasing recovery temperature, rod diameter and deformation of both Ti-Nb coated and uncoated surface. The recovery force of Ti-Nb coated rods of 6.0 and 6.5 millimeter in diameter was lower than the uncoated rods in the same diameter. However, the recovery force of 7.0-mm-diameter rods showed no significant difference between coated and uncoated surface.
Alloys ; chemistry ; Biomechanical Phenomena ; Coated Materials, Biocompatible ; Niobium ; Temperature ; Titanium

OBJECTIVE: To evaluate the rationality and validity of weighted TOPSIS method and weighted RSR method to evaluate drug supervision and supply networks construction in rural areas of Hunan . METHODS: Data of drug network construction in rural Hunan in 2010 were used to establish a comprehensive evaluation model, and weighted TOPSIS and RSR method were applied to this model and the results of which were compared to that of synthetical scored method to examine the validity. RESULTS: A comprehensive evaluation model was established, comprising of 3 primary indices, 8 secondary indices and 56 tertiary ones. The result of weighted RSR method was highly correlated to that of synthetical scored method, yet the result of TOPSIS was less correlated to the formers. All correlations were significant (P<0.01). CONCLUSION Both weighted RSR and TOPSIS are not perfect methods, but the application of the methods in drug network evaluation is scientific and effective.
China ; Computing Methodologies ; Decision Support Techniques ; Fees and Charges ; Models, Theoretical ; Pharmaceutical Preparations ; standards ; supply & distribution ; Rural Health Services

Objective:To investigate the effects of poly adenosine diphosphate ribose polymerase-1(PARP-1) inhibitor fluzoparib on proliferation, apoptosis and migration of pancreatic cancer PANC1 cells.Methods:PANC1 cells cultured in conventional culture medium were used as control group, and PANC1 cells cultured in the medium containing fluzoparib were used as fluzoparib group. The effects of fluzoparib with different concentrations on the proliferation of PANC1 cells were detected by CCK8 method, and the half inhibitory concentration (IC 50) of fluzoparib on PANC1 cells was calculated. The effect of fluzoparib on apoptosis and cell cycle of PANC1 cells was detected by flow cytometry, and the migration ability of PANC1 cells was detected by cell scratch test and Transwell chamber. Results:Compared with control group, with the increase of fluzoparib concentration and the prolongation of the action time, the cell proliferation activity of PANC1 in fluzoparib group was significantly decreased, and the differences were statistically significant (all P values <0.05). IC 50 of fluzoparib on PANC1 cells cultured for 24 h was 0.03 mmol/L. After 24 h culture, the IC 50 apoptosis rate of fluzoparib group was (32.19±2.48)%, and the apoptosis rate of control group was (21.99±6.30)%. The former was greatly higher than the latter, and the difference was statistically significant ( P<0.05). The proportion of cells in G 2/M phase was (16.28±0.62)% in the fluzoparib group and (11.64±0.88)% in the control group, and the difference between the two groups was statistically significant ( P<0.05). The migration rates of PANC1 cells in IC 50 fluzoparib group in 12 h and 24 h culture were (2.59±1.46)% and (19.76±7.84)%; and those in control group were (27.08±2.17)% and (45.92±3.61)%, respectively. The number of transmembrane cells was (348±19) cells/10 visual field in the fluzoparib group and (587±14) cells/10 visual field in the control group. The migration ability of PANC1 cells in fluzoparib group was significantly lower than that in control group ( P<0.05). Conclusions:Fluzoparib can inhibit the proliferation and migration of PANC1 cells and promote the apoptosis of PANC1 in vitro, which may be an effective drug for the treatment of pancreatic cancer.

OBJECTIVES: To evaluate residents' knowledge, attitude and behavior towards coronavirus disease 2019 (COVID-19) in Hunan Province, and to explore the factors influencing behaviors. METHODS: A self-designed questionnaire was used to conduct an online survey for 4 139 Hunan residents. The contents included general population information, residents' knowledge, attitude and practice to COVID-19. RESULTS: Mean scores of knowledge, attitude, and behavior were 29.82±3.16, 6.71±1.12, and 14.93±1.45, respectively. Residents had the highest score of major symptoms of COVID-19 (3.96±0.39), but the lowest was the main transmission routes (3.47±0.89). A total of 22.68% of the residents were very or relatively afraid of the outbreak, but 95.22% of the residents had confidence in defeating COVID-19. In behavior dimension, "handling of suspicious symptoms" had the lowest score (3.58±0.75). The behavior implementation rate of "keep the surfaces of household items clean" (80.50%), "doing more exercise, reasonable diet, working and resting regularly" (84.59%), and "avoid hand contacting with eyes, mouth or nose" (89.51%) were relatively low. Pearson correlation coefficient showed that the knowledge, attitude, and practices score were correlated with each other (knowledge vs behavior: =0.366; knowledge vs attitude: =0.041; attitude vs behavior: =0.100; all <0.05). Multiple linear regression analysis showed that the knowledge, attitude and behavior on COVID-19 were mostly influenced by education background (all <0.05), and the independent factors affecting behavior included knowledge and attitude, gender, permanent residence, education background (all <0.05). CONCLUSIONS Residents in Hunan Province have a good knowledge, attitude, and behavior to COVID-19. Nevertheless there are still weak links to be improved in all dimensions. It is necessary to strengthen knowledge and behavior of family protection, and care for residents' psychological health, especially persons with low education degree, male and rural residents.
Betacoronavirus ; China ; Coronavirus Infections ; psychology ; Health Knowledge, Attitudes, Practice ; Humans ; Pandemics ; Pneumonia, Viral ; psychology ; Surveys and Questionnaires

【Objective】 To quantitatively analyze the surgical freedom of odontioectomy via endoscopic endonasal approach. 【Methods】 Seven adult head specimens were dissected by the endoscopic transnasal approach to the sellar region and craniocervical junction. The center of sellar floor (CenSF), opticocarotid recess (LOCR), foramen magnum, atlas, atlas-occipital joint and tip of odontoid process (TOP) were exposed. The surgical freedom of TOP was calculated by using the spatial coordinate positioning system of neuronavigation, and compared with that of LOCR and CenSF. 【Results】 CenSF and LOCR were common landmarks in the endonasal endoscopic approach. When the surgical freedom between TOP and CenSF and LOCR was compared, it indicated that ① The angle of attack on axial plane (AAAP):There was a significant difference among TOP, LOCR and CenSF (5.7 ° vs. 6.9 ° vs. 8.5 °, P=0.004). The comparison between the two groups showed that TOP was less than CenSF (P=0.003). ② The angle of attack on sagittal plane (AASP): There was a significant difference among TOP, LOCR and CenSF (6.3° vs. 7.0° vs. 9.5°, P=0.009). The TOP was less than CenSF (P=0.008). ③ There was no statistical significance between TOP and LOCR in surgical freedom (P=0.604, P=0.688). 【Conclusion】 Endoscopic transnasal approach can provide sufficient surgical freedom for odontoidectomy.