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71.
体外构建子宫内膜是利用组织工程学原理,在体外构建结构、形态与功能上与体内子宫内膜相似的三维模拟体。种子细胞分离培养、生物支架材料的合理选择及体外构建方法的优化是体外构建子宫内膜的重要因素。构建的子宫内膜在病理研究、三维培养体系、胚胎发育学及移植等方面具有重要的研究意义。只有更进一步模拟自然子宫的结构,优化构建技术路线和培养条件,才可以再造出真正意义上的组织工程化子宫。  相似文献   
72.
健康人格是个体身心顺利发展的重要保证,是大学生适应社会、充分发挥自己能力的心理基础。而目前许多高等医药院校在大学生健康人格培养方面,普遍重视不够。本文从学校、教师、失学生自身三个角度,试探索出一套适合高等医药院校大学生健康人格建立和发展的培养模式,以期为对以后的心理健康教育工作有一定的启发和指导作用。  相似文献   
73.
目的 了解抗菌药物应用的基本情况。方法 将 2 0 0 1年 3月 14 3 0例住院患者病历与 2 0 0 4年 3月的 2 0 66例住院患者病历进行回顾性调查和对比分析。结果  2 0 0 1年的 14 3 0例中有 948(66 3 % )例 ,和 2 0 0 4年的 2 0 66例有 10 60例 (5 1.3 % ) ,应用了抗菌药物。结论 定期检查考评 ,严格掌握用药指征 ,是加强抗菌药物应用管理的关键。  相似文献   
74.
Selected media were compared for primary isolation and detection of oral treponemes from clinical samples. Forty-eight subgingival plaque samples from 45 patients suffering from periodontitis were anaerobically cultivated for 2 weeks at 37°C. Of the 9 media studied, Medium 10 (M10), which was supplemented with 10% rabbit serum and incubated using the plate-in-bottle method, supported the highest colony-forming units of the anaerobes. The treponemal colonies were detected at least on one medium from 83% of the subgingival plaque samples. The new oral spirochete medium in an anaerobic chamber supported the highest detection frequency of the oral treponemes (64% of samples); however, M10 in the plate-in-bottle was found to produce the highest colony-forming unit recovery of the oral treponemes (median 3.6% of the total colony-forming units). This study suggests that M10 in the plate-in-bottle and new oral spirochete medium in the anaerobic chamber are essential in cultivating oral treponemes.  相似文献   
75.
Abstract: A compact three-dimensional (3D) module is needed for hepatocyte culture in order to develop an effective hybrid artificial liver system that can retain hepa-tocellular structure and differentiated functions. We treated the 3D module with collagen gel to entrap rat hepatocytes. This method yielded a high hepatocellular density (2 times 107 cells/ml) over a period of 14 days and maintained the secretion of albumin and ureogenesis at the same level as the control monolayer method. The ammonia removal remained at 43% of the Day 0 value over 8 days of perfusion. Our data show that this approach may be useful for liver support therapy in an ex-tracorporeal circuit.  相似文献   
76.
Involvement of programmed cell death in preimplantation embryo demise   总被引:2,自引:1,他引:1  
Fragmentation is frequently observed in animal and human embryosobtained via in-vitro fertilization (IVF), and is known to beassociated with decreased pregnancy rates and poor survivalfollowing cryopreservation. We postulate that embryo fragmentationis a consequence of activated programmed cell death (PCD) andsubsequent apoptosis and discuss evidence of morphological,histological and biochemical features compatible with the occurrenceof PCD in preimplantation embryos. If PCD is an underlying causeof the high incidence of the fragmentation seen in human pre-embryos,it remains to be determined whether this is reflective of thenatural incidence of lethal chromo somes in the human populationor due to the IVF procedure and culture conditions.  相似文献   
77.
78.
Although knowledge of functional differentiation and tumour-associated changes of breast carcinomas can be gained by the application of antibodies directed against the milk fat globule membrane, more significant information may be obtained by assessment of the potential of breast carcinomas to modulate their antigenic phenotype. In this study, the extend to which primary tumours can undergo modulation in vitro has been investigated, with consideration of the suitability of organ culture in combination with the immunohistochemical detection of two milk fat globule membrane epitopes, HMFG1 and HMFG2, as methods for detecting this. The preservation of three of the 30 carcinomas assessed, all poorly differentiated, was poor after 3 days of culture. The viability of the other 27 was variable, and was greater in the better differentiated tumours and with the addition of insulin. Expression of the milk fat globule membrane epitopes was generally well maintained. Six of the carcinomas showed a significant change in antigen expression, with this being more frequent in tissues incubated with insulin. Hence, a small group of carcinomas have been identified which appear to have a greater capacity to undergo functional differentiation. Organ culture is considered to be a suitable method for maintaining the tissues in vitro for such evaluation, but the problems encountered in quantifying the immunohistochemical staining, because of antigenic heterogeneity, were such that it is suggested that other approaches be employed.  相似文献   
79.
Although extensively pursued, the central respiratory neurons have remained elusive. We departed from the more conventional physiologic and morphologic methods of system and tissue examination and cultured dissociated fetal rat cells (Fitzgerald et al., J Neurosci Res 33:579-589, 1992) from the area of the nucleus ambiguus and the nucleus tractus solitarius located within the 2 mm rostral to the obex. Pacemaker-like cells, with a regular single or bursting activity, studied at 3-5 weeks of age, responded to very small pulses of CO2 (50 ms) and low pH with an increase in spike frequency and a decrease in spike amplitude. Other irregularly beating or silent cells did not respond or else required very large pulses (> 200 ms) to do so. The pacemaker cells also responded to hypoxia induced by administration of sodium hydrosulfite with an increase in spike frequency and amplitude; high oxygen (> 600 torr) and adenosine produced a decrease in electrical activity. Most of these cells were multipolar after staining with antibodies to neuron-specific enolase (NSE) and Fragment C of tetanus toxin. They did not stain for choline acetyltransferase (ChAT). The results suggest that these cultured cells, expressing a phenotype inherently responsive to CO2 and low pH, have the characteristics of central respiratory chemoreceptors, and may be involved in the generation of the respiratory rhythm.  相似文献   
80.
A preparation of extracts from the root of the Chinese medicinal herbTripterygium wilfordii Hook was administered orally at a dose of 1 mg/kg body weight per day to 13 children with idiopathic nephrotic syndrome. Eight children, including 4 who were steroid resistant, went into remission which was maintained in 4 for up to 3 years after withdrawal of treatment. In 3 children the proteinuria lessened with the return of plasma protein concentration to normal, and in 1 child this improvement was maintained for 4 years after treatment ceased. No serious side-effects were noted, but a temporary anti-fertility activity has been noted in other studies of both men and women.  相似文献   
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