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《Saudi Journal of Biological Sciences》2017,24(6):1404-1409
Heliotropium digynum, is a shrub that has ecological importance. The height of the plant differs from one population to another and the difference in length of the inflorescence can be attributed to environmental factors, such as rainfall or type of soil and temperature. To date, no study has shed light on estimation in seed samples of H. digynum in Saudi Arabia. So, the aim is to evaluate and characterize the protein patterns of seed storage proteins of H. digynum to be used as fingerprint of this plant in Saudi Arabia. It is collected from different locations in the central region of Saudi Arabia and total protein extraction from plant was compared in SDS-PAGE. The genetic relationships among all cultivars were analyzed using UPGMA and NJ using Total Lab TL and in the same way using Jaccard Similarity Coefficient dendrogram using STATISTICA (ver.8) software. Results, our data show that amounts of protein are different, although they are of the same type or from the same geographical region. Amounts ranged between 22 and 1.5 mg/g of dry weight. Less amount of protein was obtained from the group of samples collected from Dir’iyah area, and the highest amount of protein was from the group of samples collected from Dyrab area in general. 相似文献
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Timothy Rossman Vinod Kushvaha 《Computer methods in biomechanics and biomedical engineering》2016,19(2):208-216
Quantitative computed tomography-based finite element models of proximal femora must be validated with cadaveric experiments before using them to assess fracture risk in osteoporotic patients. During validation, it is essential to carefully assess whether the boundary condition (BC) modeling matches the experimental conditions. This study evaluated proximal femur stiffness results predicted by six different BC methods on a sample of 30 cadaveric femora and compared the predictions with experimental data. The average stiffness varied by 280% among the six BCs. Compared with experimental data, the predictions ranged from overestimating the average stiffness by 65% to underestimating it by 41%. In addition, we found that the BC that distributed the load to the contact surfaces similar to the expected contact mechanics predictions had the best agreement with experimental stiffness. We concluded that BC modeling introduced large variations in proximal femora stiffness predictions. 相似文献
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《Saudi Journal of Biological Sciences》2018,25(3):487-492
To study the effect of raspberry total flavonoids on perimenopausal model in mice. Blank group, sham operation, and the rest of the mice made the menopausal model. Choose 72 mice castrated completely random divided into 6 groups for the experiment, respectively: model group, gengnianan (GNA) capsule group, soybean isoflavone soft (SIS) capsule group, high, mid and low dose group of total flavonoids of raspberry (TFR). Animals in each group were given the corresponding drugs tenth days after operation, and were given intragastrical administration of once a day for continuous administration of 21 days. Each group of mice in the administration of 18 days to determine the number of autonomic activities within 5 min, in the administration of 19–20 days to determine the incubation of the mice first entry into the darkroom and the number of shocks into the darkroom within 5 min. At 2 h after the last administration (fasting for 12 h), mice were sacrificed and serum was collected. Serum levels of E2, T, LH and FSH were measured. Dissect the uterus, uterus, thymus and spleen. Weigh the wet weight and calculate the organ index, the morphological changes of uterus, thymus and spleen were observed. The results showed that the TFR had a good therapeutic effect on the perimenopausal model of mice after giving a high, mid and low dose of raspberry flavonoids for some time. 相似文献
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《Bioorganic & medicinal chemistry letters》2014,24(15):3389-3391
Xylarianaphthol-1, a novel dinaphthofuran derivative, was isolated from a marine sponge-derived fungus of order Xylariales on the guidance of a bioassay using the transfected human osteosarcoma MG63 cells (MG63luc+). The chemical structure of xylarianaphthol-1 was determined from the 1H and 13C NMR analysis and was further confirmed by the total synthesis. Xylarianaphthol-1 activated p21 promoter stably transfected in MG63 cells dose-dependently. Expression of p21 protein in the wild-type MG63 cells was also increased by xylarianaphthol-1 treatment. 相似文献
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The 16-station RandomPOD wear test system, previously validated for prosthetic hip wear, was used in the simulation of knee wear mechanisms with a ball-on-flat test configuration. This consisted of a CoCr pin with a ground and polished spherical bearing surface (radius 28 mm) against a conventional, gamma-sterilized UHMWPE disk in serum lubrication. The biaxial motion, consisting of x and y translations, and the load was non-cyclic. Relative to the disk, the center of contact wandered within a circle of 10 mm diameter, and the average sliding velocity was 15.5 mm/s (ranging from 0 to 31 mm/s). The load varied non-cyclically between 0 and 142 N (average 73 N). In the 60-day test with 16 similar wear couples, moderate adhesive wear, the principal wear mechanism of a well-functioning prosthetic knee, dominated. This showed as a burnished, circular wear mark (diameter 13.2 mm, area 137 mm2). The wear factor was 2.04±0.03×10−6 mm3/N m (mean±95 percent confidence limit). For the first time a truly multidirectional, realistic and uniform, large capacity pin-on-disk simulation of knee wear mechanisms was implemented. 相似文献
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Yeqing Tong Xiaoxu Yin Zhihong Wang Faxian Zhan Yanwei Zhang Jianjun Ye Shuangyi Hou Yijie Geng Yang Li Xuhua Guan Yongzhong Jiang Lingyao Zhang Jifang Dai Katherine A. Mason Jiafa Liu Zuxun Lu Jinquan Cheng 《Gene》2013
Endothelial nitric oxide synthase (eNOS) plays an important role in mediating endothelium-dependent vasodilatation and antithrombotic action and is thus involved in the development of ischemic stroke (IS). Controversial results regarding the association of eNOS gene variable number of tandem repeats (VNTR) polymorphism with IS have been reported by conventional PCR-polyacrylamide gel electrophoresis methods. We aimed to identify any common association of eNOS gene VNTR polymorphism with IS in Chinese Han population by capillary electrophoresis (CE). The VNTR polymorphism of 27 bp within the eNOS intron-4 was determined by CE with specially designed tailed primers in Chinese Han patients with IS (n = 457) and matched elderly controls without IS (n = 457). Significant differences in BMI, WHR, hypertension, diabetes, smoking, TG, HDL, LDL, LDL, and FBG were observed between cases and controls. The distributions of eNOS VNTR polymorphism were not significantly associated with IS after adjustment for cardiovascular risk factors (OR = 1.18, 95% CI: 0.82–1.69). This finding was consistent with the further meta-analysis in Asians. The meta-analysis in Americans demonstrated that 4a/4b + 4a/4a genotype was significantly associated with IS risk with an OR of 1.54 (95% CI, 1.09–2.17) compared with the 4b/4b genotype. Our data suggests that BMI, WHR, hypertension, diabetes, smoking, TG, LDL, and FBG may increase the risk of IS. However, eNOS VNTR polymorphism may be not an independent major contributor for IS in Chinese Han population. The VNTR polymorphism might be associated with IS in Americans based on meta-analysis. 相似文献
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目的:研究人工髋关节置换术中股骨假体周围骨折的影响因素及其相关性,为人工髋关节置换术中股骨假体周围骨折的预防和诊治提供科学依据。方法:选取本院2012年11月至2013年9月施行髋关节置换手术的患者780例,搜集各研究对象的一般资料(年龄、性别等)以及随访观察其髋关节置换手术后股骨假体周围骨折的发生情况,把股骨假体周围骨折的发生情况与性别、年龄、固定类型等因素进行Logistic回归分析。结果:780例施行髋关节置换手术的患者中,有52例患者术后出现股骨假体周围骨折,总发生率为6.7%;其中A型31例,B型18例(B1型6例,B2型7例,B3型5例),C型3例。女性的发生率(8.5%)高于男性(4.7%),老年患者中股骨假体周围骨折的发生率最高(10.1%),生物型假体固定者的发生率(8.7%)高于骨水泥型假体固定者(3.8%),人工髋关节翻修术中股骨假体周围骨折的发生率最高(11.4%),股骨假体周围骨折发生的危险因素为女性、高龄、使用生物型假体固定,OR值分别为5.301、3.675和2.336。结论:人工髋关节置换术中的危险因素为女性、高龄、使用生物型假体固定,临床医生应在术前对行人工髋关节置换术手术者进行充分的评估,制定合理的手术方案及选择合适的固定方式。 相似文献