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排序方式: 共有132条查询结果,搜索用时 15 毫秒
1.
目的:探讨在B超引导下子宫内膜消融术治疗更年期功血的效果。方法:扩张宫颈至6.5号,吸宫,在B超监视下由子宫右前壁始向外刮凝,依次顺时针方向刮凝宫腔2周。结果:治愈31例(60.8%),有效19例(37.3%),好转1例(1.9%),无效0例。结论:电凝刀子宫内膜消融术与其他更年期功血治疗方法相比,消融的范围及深度由B超监视,安全性高,创伤小,不开刀,恢复快,并且治愈率高,更容易在临床上推广。  相似文献   
2.
PCR反应混合液的冻干处理及其应用   总被引:2,自引:1,他引:1  
本研究将除模板DNA以外的PCR反应混合液,经过真空浓缩冻成干粉状后,分别置于室温和4℃贮存,经过一定的贮藏时间后进行PCR反应,发现经冻干处理的样品能在较长的贮存时间内保持扩增活性,这将给实际工作带来很大的便利。Abstract:In this paper we introduce a new storage method of PCR ingredient.PCR mixture except DNA template has been frozen to dry powder by the DNA-Plus system.This kind of powder was stored at room temperature or 4℃.PCR has been run in different period of storage.It was discovered that the samples of lyophilization could keep activity for a long time.  相似文献   
3.
BC. Two days after supplementation with 5 microM BC in MbetaCD, cellular BC levels reached a maximum of 140+/-11 pmol/microg DNA, leveling off to 100+/-15 pmol/microg DNA until day 8. Incubation with BC dissolved in THF/DMSO resulted in a lower BC uptake of 105+/-14 pmol/microg DNA and 64+/-20 pmol/microg DNA respectively. No cytotoxic effects of these formulations were detected. The results show that the MbetaCD formulation is an improved method for investigations of carotenoids and other lipophilic compounds in in vitro test systems compared to methods using organic solvents.  相似文献   
4.
针对微生物学实验教学中存在的问题,如未突出以学生为中心的理念、难以培养学生的创新性思维、无法激发学生学习的积极性、考核无法反应学生的真实水平等,我们开展了以学生兴趣为前提、学生主动参与为抓手、提高学生创新能力为目标的系列微生物学相关开放性创新实验。采用三段式教学设计,通过文献调研、开展实验和结果总结构建了综合考核方案,达成了微生物学实验的教学目标,丰富了与理论教学紧密联系的\"基础、综合、创新\"系列化、多层次、阶梯状的专业实践教学体系。开放性创新实验项目的实施,推动了学生学习研究、科研训练和项目实践,提高了学生科创竞赛的参赛水平。开放实验也对授课教师的科研素养和教学能力有了更高的要求,做好实验室的管理,进而保障开放实验项目的顺利施行。  相似文献   
5.
M. Francz, K. Egervari and Z. Szollosi
Intraoperative evaluation of sentinel lymph nodes in breast cancer: comparison of frozen sections, imprint cytology and immunocytochemistry Objective: We analysed the utility of imprint cytology with rapid immunocytochemistry and frozen section analysis for the evaluation of sentinel lymph nodes in breast cancer patients. Methods: The sensitivity, specificity, and positive and negative predictive values have been calculated for each method individually, each pair and all three together. We compared these results with those of routinely processed paraffin sections. Results: The sensitivity and specificity of each of the three methods for detection of metastatic carcinoma were as follows: 69.4% and 97.8% for touch imprint cytology; 58.3% and 100% for frozen sections; 68.5% and 98.9% for rapid immunocytochemistry. When the methods were combined, the highest accuracy was achieved by touch imprint cytology, frozen sections, touch imprint cytology plus rapid immunocytochemistry, or touch imprint cytology frozen section analysis and rapid immunocytochemistry, each of these having identical sensitivity and specificity of 72.2% and 97.8%, respectively. Conclusions: In our study the combined accuracy of the three methods was the same as combining touch imprint cytology and frozen sections or touch imprint cytology plus rapid immunocytochemistry. Rapid immunocytochemistry provides an additional parameter and preserves tissue for permanent sections.  相似文献   
6.
Several studies have indicated that olfactory responses are impeded byamiloride. Therefore, it was of interest to see whether, and if so which,olfactory epithelial cellular compartments have amiloride- sensitivestructures. Using ultrastructural methods that involved rapid freezing,freeze-substitution and low temperature embedding of olfactory epithelia,this study shows that, in the rat, this tissue is immunoreactive toantibodies against amiloride sensitive Na(+)- channels. However, microvilliof olfactory supporting cells, as opposed to receptor cilia, contained mostof the immunoreactive sites. Apices from which the microvilli sprout andreceptor cell dendritic knobs had much less if any of theamiloride-antibody binding sites. Using a direct ligand-bindingcytochemical method, this study also confirms earlier ones that showed thatolfactory receptor cell cilia have Na+, K(+)-ATPase. It is proposed thatsupporting cell microvilli and the receptor cilia themselves havemechanisms, different but likely complementary, that participate inregulating the salt concentration around the receptor cell cilia. In thisway, both structures help to provide the ambient mucous environment forreceptor cells to function properly. This regulation of the saltconcentration of an ambient fluid environment is a function that theolfactory epithelium shares with cells of transporting epithelia, such asthose of kidney.  相似文献   
7.
GABA_B受体变构剂药学研究进展   总被引:1,自引:0,他引:1  
γ-氨基丁酸B受体(GABAB receptor,GABABR)是最具有药理学意义的药物靶点之一,具有复杂而精细的激活机制。传统的GABABR靶点药物开发集中于激动剂和拮抗剂,这类药物受到多种因素的制约,包括较强的副作用、药物代谢困难、机体耐药性明显等。变构剂结合于正构位点之外,能够调节GABABR异源二聚体亚基或结构域间的相互作用。正向变构剂(positiveallosteric modulators,PAMs)和负向变构剂(negative allosteric modulators,NAMs)分别可以提高或降低GABABR的活性,并具有较高的特异性和药物安全性,同时还能够保持GABABR信号在时间和空间上的可控性。变构剂为GABABR靶点药物开发提供了新思路。  相似文献   
8.
唐杨欣  皮杰  刘新华  向建国  曾聪  李德亮 《生态学报》2023,43(10):4250-4259
河蚬是一类在我国广泛分布的底栖贝类,具有重要的经济价值及生态价值。近年来,河蚬野生资源量锐减,了解河蚬在国内的潜在分布能为河蚬的保护和合理利用提供重要参考。基于河蚬在中国的136个分布点和8个环境因子,采用ENMeval包和biasfile优化后的最大熵模型(MaxEnt)预测分别河蚬现代和未来(2041—2060年和2081—2100年) 6个气候情景下的潜在分布。综合Jackknife检验、置换重要值和环境因子贡献率评估影响现代河蚬潜在分布的主要因子,比较未来气候情景下潜在适生区差异从而分析预测河蚬适宜分布的变化。结果表明:(1)优化后的MaxEnt模型预测准确度极高,平均AUC值为0.900±0.037,平均AUCDIFF值为0.019,现代河蚬潜在分布区域总面积为188.33×104 km2,主要集中在长江流域、海河流域、淮河流域、珠江流域、东南沿海区域以及黄河流域下游和渤海湾沿岸区域。(2)影响河蚬潜在分布的主要环境因子为海拔、温度(年均温和温度年较差)和降水(年降水量)。(3)在未来6种气候情景下,河蚬主要潜...  相似文献   
9.
  总被引:3,自引:0,他引:3  
We characterized the function of two rice phosphate (Pi) transporters: OsPHT1;9 (OsPT9) and OsPHT1;10 (OsPT10). OsPT9 and OsPT10 were expressed in the root epidermis, root hairs and lateral roots, with their expression being specifically induced by Pi starvation. In leaves, expression of the two genes was observed in both mesophyll and vasculature. High‐affinity Km values for Pi transport of OsPT9 and OsPT10 were determined by yeast experiments and two‐electrode voltage clamp analysis of anion transport in Xenopus oocytes expressing OsPT9 and OsPT10. Pi uptake and Pi concentrations in transgenic plants harbouring overexpressed OsPT9 and OsPT10 were determined by Pi concentration analysis and 33P‐labelled Pi uptake rate analysis. Significantly higher Pi uptake rates in transgenic plants compared with wild‐type plants were observed under both high‐Pi and low‐Pi solution culture conditions. Conversely, although no alterations in Pi concentration were found in OsPT9 or OsPT10 knockdown plants, a significant reduction in Pi concentration in both shoots and roots was observed in double‐knockdown plants grown under both high‐ and low‐Pi conditions. Taken together, our results suggest that OsPT9 and OsPT10 redundantly function in Pi uptake.  相似文献   
10.
鄂西大蓟根的化学成分的研究   总被引:2,自引:0,他引:2  
本题对菊科蓟属植物鄂西大蓟根Cirsium henryi的化学成分进行系统研究。采用硅胶柱色谱法分离了五个单体成分并以光谱分析法鉴定它们的结构:乙酰丁香酸(p-Hydroxycinnamic acid,1),原儿茶酸(protocate-chuic acid,2),香草酸(vanillic acid,3),二羟丙基软脂酸酯(2,3-dihydroxypropyl hexadecanoate,4)和胡萝卜苷(glucoraphenin,5)。这些化合物均为首次从该植物中分离得到。  相似文献   
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