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81.
Richard H. C. Bonser 《仿生工程学报(英文版)》2006,3(1):39-41
1 Introduction Biomimetics or bionics is having an increasing role in innovation[1]. It offers the promise of novel routes to technological innovation; a recent paper highlighted the potential of studies of biological systems to initiate patents in the engineering sciences and technology[2]. Media coverage, particularly in business periodicals is increasing, for example, The Economist recently re- ported on the growth of biomimetics and its impact on technology[3]. There are two principal rou… 相似文献
82.
为了获得具有药用价值的活性天然产物,采用4种大孔吸附树脂对柴达木沙漠链霉菌(Streptomyces qaidemensis)S10T发酵液进行静态吸附和解吸实验,优化分离工艺。结果显示,AB-8型树脂具有良好的吸附和解吸性能,该树脂对柴达木沙漠链霉菌S10T发酵液中的活性天然产物吸附工艺为发酵液pH值9,吸附时间4 h,洗脱液70%甲醇溶液。经正向硅胶、反相硅胶和葡聚糖凝胶Sephadex LH-20分离得到了一个化合物,1H-NMR和13C-NMR结合高分辨质谱(LC-HR-MS)鉴定该化合物为阿糖腺苷(vidarabine),是一种具有抗病毒活性的核苷类抗生素,并简单探究了其在柴达木沙漠链霉菌中的生物合成过程。 相似文献
83.
基于AnyBodyTM技术的人体运动建模方法 总被引:3,自引:0,他引:3
人体运动的建模与仿真是当今运动生物力学研究的一个热点.利用数值模型研究人体的运动规律,是人体运动研究的一个重要手段和有效工具.其关键技术在于应用逆向运动学方法求解人体运动,并获取人体运动中各个肌肉力学上技术参数.文中主要探讨基于AnyBodyTM System软件人体运动仿真的建模方法来研究人体运动力学规律,结合The AnyBodyTM system对人体运动具体应用,说明The AnyBodyTM system技术在人体运动仿真领域的优势. 相似文献
84.
85.
Germ cell transplantation in goats 总被引:19,自引:0,他引:19
Honaramooz A Behboodi E Blash S Megee SO Dobrinski I 《Molecular reproduction and development》2003,64(4):422-428
Transplantation of spermatogonial stem cells provides a unique approach for the study of spermatogenesis and manipulation of the male germ line. This technique may also offer an alternative to the currently inefficient methods of producing transgenic domestic animals. We have recently established the technique of spermatogonial transplantation, originally developed in laboratory rodents, in pigs, and this study was aimed to extend the technique to the goat. Isolated donor testis cells were infused into the seminiferous tubules of anesthetized recipient goats through an ultrasonographically-guided catheter inserted into the rete testis. Donor cells were obtained by enzymatic digestion of freshly collected testes from immature goats (either from the recipients' contralateral testis or from unrelated donors). Prior to transplantation, testis cells were labeled with a fluorescent marker to allow identification after transplantation. Recipient testes were examined for the presence and localization of labeled donor cells at 3-week intervals up to 12 weeks after transplantation. Labeled donor cells were found in the seminiferous tubules of all testes, comprising 10-35% of the examined tubules. Histological examination of the recipient testes did not reveal evident tissue damage, except for limited fibrotic changes at the site of needle insertion. Likewise there were no detectable local or systemic signs of immunologic reactions to the transplantations. These results indicate that germ cell transplantation is technically feasible in immature male goats and that donor-derived cells are retained in the recipient testis for at least three months and through puberty. This study represents the first report of germ cell transplantation in goats. 相似文献
86.
关于周口店第15地点石器类型和加工技术的研究 总被引:6,自引:3,他引:3
在周口店第 15地点经过加工的石器中 ,刮削器占近 93%。其它石器类型包括砍砸器、尖刃器、石锥、凹缺器、雕刻器和薄刃斧。石器由锤击加工。绝大多数标本向一面加工。石片石器多为正向加工。大多数石器个体很小 ,形态不规则 ,修疤呈鳞状 ,深浅、大小不一。少数标本的修疤浅平、规则而平行。统计分析显示在各类器型之间存在着明显的大小与加工上的区别。单边刃刮削器的各亚型之间在大小、加工长度和深度以及刃角和刃形诸方面不存在明显的差异 ,说明这些刮削器在刃口形态 (直、凸与凹 )方面的的变异主要取决于毛坯的原始形态 ,而非代表类型与功能的不同。变量相关分析揭示石器的大小与加工程度和原坯的大小与形态紧密相关。 相似文献
87.
Microarray profiling of gene expression patterns in bladder tumor cells treated with genistein 总被引:6,自引:0,他引:6
Chen CC Shieh B Jin YT Liau YE Huang CH Liou JT Wu LW Huang W Young KC Lai MD Liu HS Li C 《Journal of biomedical science》2001,8(2):214-222
Microarray technology was used to gain an insight into the molecular events of tumor cell growth inhibition mediated by the soy isoflavone genistein. For this, a susceptible bladder tumor line TCCSUP was treated with the inhibitory dose (50 microM) of genistein for various periods of time, followed by mRNA isolations, cDNA probe preparations, and hybridization individually to cDNA chips containing 884 sequence-verified known human genes. After analyzing the hybridization signals with a simple quantitative method developed by this study, we detected that egr-1, whose expression has been associated with proliferation and differentiation, was transiently induced and this expression pattern was later confirmed by RT-PCR. Thus, microarray technology is a reliable and powerful tool for profiling gene expression patterns in many biological systems related to cancer. We further detected many groups of genes with distinct expression profiles and most of them encode for proteins that regulate the signal transduction or the cell cycle pathways. These genes warrant further investigation as regards their roles in the susceptibility of the tumor cell line to the antitumor drug. 相似文献
88.
A near infrared spectroscopic method was developed to determine drug content in a 20% (wt/wt) ibuprofen and spray-dried hydous
lactose blend. A blending profile was obtained after blending for 0.5, 1, 3, 5, 10, and 20 minutes. Stream sampling was used
to collect about 20 blend samples at each of the blending times from a laboratory scale V-blender. The samples collected were
used to develop a near infrared calibration model. The calibration model was then used to determine the drug content of unknown
samples from 2 validation blends. The validation blends were not included in the calibration model; they were used to evaluate
the effectiveness of the calibration model. A total of 45 samples from the 2 validation blends were predicted by the near
infrared calibration model and then analyzed by a validated UV spectrophotometric method. The root mean square error of prediction
for the first validation blend was 5.69 mg/g and 3.30 mg/g for the samples from the second blend. A paired t test at the 95%
confidence level did not indicate any differences between the drug content predicted by the near infrared spectroscopy (NIRS)
method and the validated UV method for the 2 blends. The results show that the NIRS method could be developed while the blending
profile is generated and used to thoroughly characterize a new formulation during development by analyzing a large number
of samples. The new formulation could be transferred to a manufacturing plant with an NIRS method to facilitate blend uniformity
analysis. 相似文献
89.
90.
Curran S Hill L O'Grady G Turic D Asherson P Taylor E Sham P Craig I Vaughan P 《Molecular biotechnology》2002,22(3):253-262
Association studies using genome scans to identify quantitative trait loci for multifactorial disorders, with anything approaching
reasonable power, have been compromised by the need for a very dense array of genetic markers and large numbers of affected
individuals. These requirements impose enormous burdens on the genotyping capacity for most laboratories. DNA pooling has
been proposed as a possible approach to reduce genotyping costs and effort. We report on the application of the SNaPIT™ technology
to evaluate allele frequencies in pooled DNA samples and conclude that it offers a cost effective, efficient and accurate
estimator and provides several advantages over competing technologies in this regard. 相似文献