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1.
Reaction chemistry of gossypol and its derivatives 总被引:1,自引:0,他引:1
James A. Kenar 《Journal of the American Oil Chemists' Society》2006,83(4):269-302
Gossypol, a complex polyphenolic compound, is a naturally occurring highly colored yellow pigment found in the small intercellular
pigment glands in the leaves, stems, roots, and seed of cotton plants. In cottonseed, gossypol contributes to its toxicity
and therefore it is regarded as an unwanted processing component. It was not until its antitumor and male infertility activities
were discovered that gossypol was considered as a valueadded natural product from cottonseed with useful physiological and
chemical properties. These serendipitous discoveries created much excitement, and an enormous amount of research on gossypol
has ensued. Since then, much research has focused on the preparation of suitable gossypol derivatives for medicinal applications.
This review summarizes current knowledge about gossypol, its stereochemistry, tautomerism, and the many varied reactions the
gossypol molecule can undergo. 相似文献
2.
PIXE(质子激发X射线发射)分析法适合分析生物医学样品中的微量元素。分析血清不仅取样方便和制靶容易,而且能观察某些疾病与血中微量元素异常的关系。 棉酚是我国发现的男性避孕药,具有肯定的抗生育作用。但也发现个别用药者出现肌无力等症。我们考虑到棉酚的副作用可能与它对人体内某些元素的影响有关。本实验用PIXE法分析大鼠血清中的微量元素,观察了醋酸棉酚对这些元素的影响。 相似文献
3.
了解乌鲁木齐市流动育龄妇女的避孕状况,为今后开展避孕方法知情选择优质服务提供参考。采用分层-整群-随机抽样的方法,对18~50岁符合条件的对象进行问卷调查,主要包括人口学特征、避孕措施的使用情况等。采用卡方检验和多因素Logistic回归方法进行统计分析。本次调查的106 568例流动育龄妇女中,避孕方法使用比例为92.78%,避孕方法的选择依次为宫内节育器(65.74%)、药物(23.17%,包括口服避孕药、皮下埋植剂、避孕针等含药避孕方法)、避孕套(9.06%)、绝育术(2.03%)。多因素Logistic回归分析显示民族、学历、职业、婚姻状况和性生活频率对避孕方法的使用有影响。应根据不同民族的情况和流动育龄妇女的人口学特征,提供有针对性和个性化的避孕方法知情选择指导和服务。 相似文献
4.
宫内节育器及其耐蚀性研究进展 总被引:1,自引:0,他引:1
综述了宫内节育器的种类及特点、常用材料铜的耐蚀
性等研究进展,并讨论了铜的纯度、介质pH值、溶解氧、血清白蛋白等因素对铜的腐蚀行为的影响,进而展望了宫内节育器的发展趋势及耐蚀性研究方向. 相似文献
5.
目的 观察醋酸甲孕酮微晶水混悬剂(MPA)的避孕作用、副反应和可接受性。方法 292名哺乳与非哺乳妇女对象在接受详细咨询并签署知情同意书后进入试验, 每三个月一次接受注射并随访, 观察期一年。结果 用药期间无一 例发生妊娠, 避孕有效率为100%。哺乳与非哺乳妇女一年总停针率分别为5. 05%和11. 4%。主要副反应为不规则出血, 哺乳妇女与出血有关的主诉发生率(16. 1%)明显高于非哺乳妇女(5. 1%, P< 0. 01)。 未见其他严重副反应。结论 MPA是一种高效的长效避孕针, 经详细咨询后在中国妇女中可获得良好的可接受性, 尤其适合产后哺乳妇女使用。 相似文献
6.
The protein adenine nucleotide translocase (ANT) is localized in the mitochondrial inner membrane and plays an essential role in transporting ADP into the mitochondrial matrix and ATP out from the matrix for cell utilization. In mammals there are four paralogous ANT genes, of which ANT4 is exclusively expressed in meiotic germ cells. Since ANT4 has been shown essential for spermatogenesis and male fertility in mice, inhibition of ANT4 appears to be a reasonable target for male contraceptive development. Further, in contrast to ANT1, ANT2 and ANT3 that are highly homologous to each other, ANT4 has a distinguishable amino acid sequence, which serves as a basis to develop a selective ANT4 inhibitor. In this study, we aimed to identify candidate compounds that can selectively inhibit ANT4 activity over the other ANTs. We used a structure-based method in which ANT4 was modeled then utilized as the basis for selection of compounds that interact with sites unique to ANT4. A large chemical library (>100,000 small molecules) was screened by molecular docking and effects of these compounds on ADP/ATP exchange through ANT4 were examined using yeast mitochondria expressing human ANT4. Through this, we identified one particular candidate compound, [2,2′-methanediylbis(4-nitrophenol)], which inhibits ANT4 activity with a lower IC50 than the other ANTs (5.8 μM, 4.1 μM, 5.1 μM and 1.4 μM for ANT1, 2, 3 and 4, respectively). This newly identified active lead compound and its chemical structure are expected to provide new opportunities to optimize selective ANT4 inhibitors for contraceptive purposes. 相似文献
7.
室温快速固化医用聚氨酯避孕栓的制备与性能研究 总被引:3,自引:0,他引:3
以三乙醇胺、乙二胺为扩链剂,采用预聚体法制得室温快速固化医用聚氨酯避孕栓,研究了含有扩链剂混合物的反应性能及前期流动性,测试了力学性能及环境适应性。结果表明,用该扩链剂制备的聚氨酯在室温条件下的固化时问为25min;可在反应开始后15min内将混合物用注射器推动并可在人体内固化成型;生戍的聚氨酯弹性体避孕栓的柔软性、环境适应性均较好。 相似文献
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9.
目的 比较中国妇女单剂及连续口服复方左旋炔诺孕酮长效避孕片后体内左旋炔诺酮(LNG)的药代动力学变化,为长期应用该长效避孕片的安全性提供依据。方法 9例健康育龄妇女于月经第5天口服复方左旋炔诺孕酮长效片(左旋炔诺孕酮6mg+炔雌醚3mg),每月1片,连续服用1年。于第1和第12次给药前及给药后不同时间取血,放射免疫法测定血清LNG浓度,并采用自身对照比较单剂和长期给药后LNG的药代动力学特征。结果 首次单剂给药后LNG药-时曲线呈二室开放模型,分布半衰期(αT1/2)为2.86±1.60小时,消除半衰期(βT1/2)为1.52±0.35天。血清LNG于2.56±1.13小时达峰浓度;血药峰值水平(Cmax)存在明显的个体差异,平均为141.36±70.20nmol/L。服用第12片后LNG平均Cmax为314.83±128.55nmol/L,显示连续给药后血LNG峰浓度显著升高。第1和第12次用药后AUC0~∞分别为182.42±135.85nmol/L·d-1和601.60±320.99nmol/L·d-1,两者亦有显著的统计学差异。第12次服药后Tmax为2.11±0.78小时,与单次给药相比无显著变化。第12次服药后LNG平均βT1/2为1.67±0.48天,与单剂给药相比亦无统计学差异,表明多次给药后药物的代谢速率并未发生明显改变,且21天体内LNG血浓度已降至0.058±0.069nmol/L(<100pg/ml)。结论 长期应用该复方口服避孕片并不引起受试者体内LNG的明显蓄积。 相似文献
10.