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31.
目的,进行胫骨上端内部结构和外部形状的模拟。方法,采用高阶非线性骨再造速率方程和有限元方法相结合,引入拓扑优化的思想,选取大于模拟的胫骨上端外形的模拟域,从不固定外形出发,对正常力学环境下的胫骨上端内部结构及外部形状进行模拟。结果,模拟的胫骨上端的外部形状和内部结构与真实结构十分接近。 相似文献
32.
A novel methodology for characterization of animal sperm shape involving the use of a spectral approach to multiscale curvature estimation is proposed. By using the derivative property of the Fourier transform, allied to Gaussian smoothing, accurate estimates of the curvature along the sperm contour can be obtained in such a way that the curvature peaks corresponding to the sperm head vertices can be effectively identified. The measurements derived from such a processing, namely the width of the basal region of the head, the centralization of tail implantation, and the multiscale bending energy, provide valuable resources for fertility and phylogenetic studies. 相似文献
33.
Rosenson-Schloss RS Vitolo JL Moghe PV 《Medical & biological engineering & computing》1999,37(2):257-263
Leukocytes adherent to the surfaces of both vascular biomaterials and normal blood vessels experience blood flow induced shear stress. The goal of the reported studies was to investigate the effect of fluid flow on the morphology, phagocytic function and stress response induction in adherent immune cells. Shear approximating arterial, venous and intermediate levels were applied onto glass-adherent IC21 macrophages in a temperature-controlled parallel plate flow system. The results indicate that fluid flow induces a shear-dependent physiological stress response in adherent macrophages and that significant morphological changes accompany macrophage responses to shear stress. In addition, arterial flow conditions induce not only significant cell polarisation, but also enhanced phagocytic ingestion in glass-adherent IC21 macrophages. These findings suggest that blood flow induced shear stress may not only be consequent to adherent leukocyte activation, but may also be integral to the regulation of adherent leukocyte behaviour in vivo. 相似文献
34.
背景与目的 :检测超微生物钙颗粒剂作为保健食品的安全性。材料与方法 :小鼠经口急性毒性、二项致突变试验(小鼠骨髓嗜多染红细胞微核试验、小鼠精子畸形试验)以及30d喂养实验。结果 :超微生物钙颗粒剂对两种性别的SPF级昆明种小鼠经口毒性,一次灌胃量达10g/kg,两周内动物未见明显中毒症状,无动物死亡,按急性毒性分级标准规定,该受试物属实际无毒级。二项致突变试验结果均为阴性。30d喂养试验结果表明:该受试物对雌性大鼠低、中、高剂量为1.71、3.35、6.82g/kg剂量(分别相当于人群推荐量的26、50、102倍) ,对雄性大鼠低、中、高剂量为1.82、3.48、6.99g/kg(分别相当于人群推荐量的27、52、105倍)对Wistar大鼠的临床检查、血液学、生化学、脏器重量和系数以及病理组织学等指标无明显影响 ,未发现该受试物有明显的毒性作用。结论 :超微生物钙颗粒剂作为保健食品是安全的 相似文献
35.
36.
腹腔镜腹膜阴道成形术的临床研究 总被引:3,自引:0,他引:3
目的探讨腹腔镜腹膜阴道成形术在妇科领域的应用价值。方法回顾性分析腹腔镜腹膜阴道成形术16例(研究组)和传统方法羊膜阴道成形术16例(对照组)患者的手术情况和术后情况。结果两组患者在年龄、病史、症状体征等方面无显著差异(P>0.05)。研究组术中出血(61±7.5)ml,对照组出血(102±23.7)ml(P>0.05);研究组手术时间(100±46.6)min,对照组手术时间(168±73.7min)(P<0.05);研究组术后有尿路刺激症状者仅1例,而对照组有尿路刺激症状者9例;研究组术后不良反应较对照组大为减少;研究组阴道长度(9.3±0.7)cm,宽度(3.5±0.6)cm,对照组阴道长度(5.4±0.64)cm,宽度(2.3±0.5)cm,两组有显著性差异(P<0.05),研究组性生活满意程度比对照组高。结论腹腔镜腹膜阴道成形术,是一种更安全、有效、创伤小的手术方式,可以提高先天性无阴道患者的生活质量。 相似文献
37.
赵建勋 《中华实用中西医杂志》2005,18(20):1259-1260
采用肛门皮瓣成形术同内扎外切法比较治疗147例混合痔患者,肛门皮瓣成形术手术一次性成功率100%,随访1~3年未见复发,该术式尽可能清除内外痔组织,保留正常肛管皮肤及粘膜组织,防止术后出血、肛门狭窄及水肿,有效缩短愈合时间,同时皮瓣移植使肛周平坦,因而该术式优于内扎外切法,既能达到治疗目的,又起到肛门整形目的。 相似文献
38.
A serine protease homologue Bombyx mori scarface induces a short and fat body shape in silkworm
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R.‐X. Wang X.‐L. Tong T.‐T. Gai C.‐L. Li L. Qiao H. Hu M.‐J. Han Z.‐H. Xiang C. Lu F.‐Y. Dai 《Insect molecular biology》2018,27(3):319-332
Body shape is one of the most prominent and basic characteristics of any organism. In insects, abundant variations in body shape can be observed both within and amongst species. However, the molecular mechanism underlying body shape fine‐tuning is very complex and has been largely unknown until now. In the silkworm Bombyx mori, the tubby (tub) mutant has an abnormal short fat body shape and the abdomen of tub larvae expands to form a fusiform body shape. Morphological investigation revealed that the body length was shorter and the body width was wider than that of the Dazao strain. Thus, this mutant is a good model for studying the molecular mechanisms of body shape fine‐tuning. Using positional cloning, we identified a gene encoding the serine protease homologue, B. mori scarface (Bmscarface), which is associated with the tub phenotype. Sequence analysis revealed a specific 312‐bp deletion from an exon of Bmscarface in the tub strain. In addition, recombination was not observed between the tub and Bmscarface loci. Moreover, RNA interference of Bmscarface resulted in the tub‐like phenotype. These results indicate that Bmscarface is responsible for the tub mutant phenotype. This is the first study to report that mutation of a serine protease homologue can induce an abnormal body shape in insects. 相似文献
39.
This article proposes an indirect measurement method based on a dimensional and shape analysis of forgings for the evaluation of the manufacture and the proper operation of the key elements of the crank press, in which after modernization, a quick tool assembly based on SMED (Single Minute Exchange of Die) was implemented. As a result of the introduced changes aiming at improving the forging aggregate and increasing the production efficiency, errors were observed on the manufactured products-forgings in the form of twists and joggles. In order to solve the problem, a lot of advanced methods was used, including: dynamic system of deformation analysis, numerical modeling and as well as dimensional and shape analysis by 3d scanning. Despite the above, this approach (classic way) did not solve the problem. A proprietary method with the use of 3D reverse scanning was proposed, which allows to solve the problem of forgings errors. Based on the measurement results and analyses for a few variants of production cycles, the necessary changes were obtained, making it possible to minimize the errors and obtain proper products in respect of geometry and quality. 相似文献
40.