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31.
目的从三列凹顶藻Laurenciatristicha中寻找具有多样性结构的倍半萜化学成分,供药理活性筛选。方法采用凝胶柱色谱、硅胶柱色谱、重结晶和高效液相色谱等方法进行分离;借助包括一维和二维NMR等波谱方法和X-单晶衍射鉴定化合物的结构;用MTT法对得到的化合物进行细胞毒活性评价。结果分离得到5个倍半萜类化合物,分别鉴定为海兔阿普里素(aplysin,)、海兔阿普里醇(aplysinol,)、去溴海兔阿普里醇(debro-moaplysinol,)、凹顶藻联苯(laurebiphenyl,)、约翰斯顿醇(johnstonol,);在人肿瘤细胞株HCT-8、Bel-7402、BGc-823、A549和HeLa模型上,化合物对所有细胞株均显示毒性,化合物对HeLa细胞显示中等强度的细胞毒活性,其他化合物对所有细胞株均无明显毒性,IC50均大于10.0μg/mL。结论化合物~均为首次从三列凹顶藻中得到,化合物对HeLa细胞具有中等强度的选择性细胞毒活性,化合物对所有细胞株均显示毒性。  相似文献   
32.
目的总结利用骨外固定器行胫骨迁移治疗血栓闭塞性脉管炎的护理经验.方法对35例血栓闭塞性脉管炎37条患肢应用骨外固定器迁移胫骨治疗.术前积极处理患肢、有效的心理护理,术后严密观察,做好骨外固定器迁移胫骨的护理.结果 32例间歇性跛行距离增加;27例夜间静息痛均得到缓解;7例足趾缺血坏死中除3例术后患肢缺血加重截肢外,余4例患肢供血改善,坏死区域结痂愈合;总有效率91.9%.结论全面、准确地评估患者,完善术前准备及术后正确迁移指导可提高骨外固定器行胫骨迁移治疗血栓闭塞性脉管炎的有效性.  相似文献   
33.
The effects of daily oral administration of a high dose of 10 mg norethisterone acetate (NET-Ac.)/kg/day over 14 weeks on serum lipid and lipoprotein parameters as well as on blood coagulation were investigated in female monkeys (M. fascicularis). Measurements of lipids and lipoprotein cholesterol were performed in weeks —5 and — 1 before treatment and in weeks 4, 8 and 12 after treatment. In addition, various blood coagulation and fibrinolytic parameters were determined in weeks 11–14 after treatment with NET-Ac. Furthermore, the serum levels of norethisterone (NET) were determined in order to monitor the real systemic compound exposure and revealed that Cmax and AUC (0–3 h) values reached for norethisterone in this experiment in monkeys were about 25 times higher than those obtained after an oral contraceptive dose of NET-Ac. in women.

The results of lipid and lipoprotein cholesterol determinations showed decreases in serum total lipids, phospholipids, triglycerides and total cholesterol associated with similar decreases in HDL-, LDL- and VLDL-cholesterol fractions after NET-Ac.-treatment in monkeys. These effects were observed from week 4 onwards and maintained their magnitude up to week 12 after treatment. Since both HDL- and LDL-cholesterol fractions decreased, the HDL/LDL-ratio remained almost unchanged. Thus, the results obtained in this study after high-dose treatment with NET-Ac. in monkeys did not indicate any changes of lipid and lipoprotein parameters which in humans are supposed to be associated with an increased risk of cardiovascular lesions, namely a decrease in HDL- and increase in LDL-cholesterol fractions.

The results of blood coagulation and fibrinolytic parameters showed increased antithrombin-III and plasminogen levels besides minor changes in other parameters, thus indicating that NET-Ac. -treatment does not contribute to an increased risk of cardiovascular thrombotic events in the cynomolgus monkey.  相似文献   

34.
We describe a simple direct extraction method for the gas-liquid chromatography determination of serum valproic acid. The working range for the assay is 2-180 mg/L and our within-run precision was 5.8 and 4.3% at the 40 and 90 mg/L concentrations respectively. Hemolyzed and lipemic sera as well as samples from patients with hyperbilirubinemia and from patients with decreased renal function were put through the assay and no interfering peaks were noted. Interference occurred when teflon-lined screw caps were used during the extraction step. The method was proven to be accurate by linear regression analysis of samples containing weighed-in amounts of valproic acid. The above assay was compared to an enzyme immunoassay technique (EMIT). The working range for the latter is 10-150 mg/L and the with-run precision was 10.8 and 5.9% and 90 mg/L concentration respectively. Samples were run by both the gas-liquid chromatograph and enzyme immunoassay methods and gave very similar results over the range 16-139 mg/L.  相似文献   
35.
The human prostatic urethra has been investigated by means of scanning electron microscopy. On the posterior wall of the urethra, the seminal colliculus with the orifices of the ejaculatory ducts is clearly detectable. The upper portion of the prostatic urethra shows a typical transitional epithelium with large superficial cells of a ruffled appearance. In the lower portion of the organ (underneath the openings of the ejaculatory ducts), the apical pattern of the cells varies considerably. Four main aspects are recognizable: apices provided with microvilli, dome-shaped apices with an almost smooth surface, large apices with labyrinthic microplicae and ciliated apices. Also, apices showing intermediate characteristics can be noted. The functional significance of the morphological patterns as well as the possibility of a transition among the various types of surface structures are discussed.  相似文献   
36.
目的探讨犬双肺序贯性移植时供肺的采取及受体移植手术技巧。方法犬16条,体重差异<5%的随机配对作为供受体进行双肺序贯移植实验共8次,移植右肺钳夹左房时采用了‘v’钳夹技术,并检测左肺及右肺术后0.5、1、2 h各进行血气分析、肺水含量及电镜下超微结构,了解术后肺功能。结果移植右肺时采取的‘v’型钳夹术良好地解决了钳夹左房时因回心血量受阻而引起的心功能不全。术后检测结果表明移植后肺功能良好。结论掌握了犬双肺序贯性移植的全过程,"V"形双阻断钳夹左心房技术提高了犬肺移植的成功率。  相似文献   
37.
Objectives Recent studies have described regional differences in the electrophysiology and pharmacology of ventricular myocardium in canine, feline, rat, guinea pig, and human hearts. This has been shown to be due to a smaller IKs and a lager sodium-calcium exchange current (INa-Ca) and late INa in M region (deep subepicardial to midmyocardial). Studies from our laboratory have found a new repolarization current-nonselective cation current (NSCCs) existing in rabbit right ventricular myocytes. Methods We examined the characteristics of NSCCs in epicardial, M region, and endocardial cells isolated from the rabbit left ventricle with standard microelectrode and whole-cell patch-clamp techniques. The permeability to Na , K , Li , Cs but not to Cl- indicating that it was a nonselective cation current. Gd3 (0.1 mmol/l) and La3 (0.1 mmol/l) can block the current markedly. Results Further characterization of NSCCs was significantly smaller in M cells than in epicardial and endocardial cells. NSCCs current density was significantly smaller in M cells than in epicardial and endocardial cells. With repolarization to -80 mV, INs current density was (-0.44±0.05) PA/PF in endocardial cells, (-0.12±0.05) PA/PF in M cells and (-0.28±0.07) PA/PF in epicardial cells; and with repolarization to 30 mV, INs current density was (1.09±0.29) PA/PF in endocardial cells, (0.38±0.09) PA/PF in M cells and (0.91±0.32) PA/PF in epicardial cells. Conclusions Transmural dispersion of repolarization was due to the heterogeneity of NSCCs in rabbit left ventricle epicardial, endocardial myocytes and M cells. These findings may advance our understanding of the ionic basis for our understanding of factors contributing to the development of cardiac arrhythmias.  相似文献   
38.
西医院校在中医学教学方面亟待解决的几个问题   总被引:1,自引:0,他引:1  
西医院校的中医学教育,在学时、教材、师资等方面存在着诸多制约因素。要全面提高西医院校的中医学教学质量,必须摆正其教育地位,调整和充实教学内容,加强师资队伍建设,改进教学方式与方法,逐步建立健全全新的中医学教学模式。  相似文献   
39.
Remote telemetry may facilitate the management of implantable devices. We tested the reliability of a new automatic, wireless home monitoring (HM) system that archives data every 24 hours. We retrospectively analyzed archival data from 276 consecutive pacing system implants to define temporal atrial fibrillation (AF) patterns and associated ventricular rate. An "AF day" was defined by a >20%/24 hour mode switch (MS) duration, irrespective of the MS number. Management decisions resulting from transmissions were noted. A pilot study confirmed that 89% of 22,356 transmissions were successful, of which >90% were received in <5 minutes. Data integrity was 100% preserved. Overall, AF developed in 29 patients (10.5%), representing a total of 645 AF days (mean = 22.2 ± 29.6 AF, median = 9 days), over 12 ± 2 months of monitoring. AF was infrequent (50% of 24 hours. Ventricular rates during 645 AF days in 29 patients averaged 95.1 ± 9.9 beats/min (median = 94 beats/min). Ventricular rates were >80 beats/min in 25 ± 30 AF days (median = 11 days). HM enabled rapid anticoagulation decisions. In recipients of implantable devices, automatic wireless telemetry with HM was efficient and reliable. Its application may overcome some current challenges in AF management by early notification and precise measurement of both AF burden and ventricular rate during AF.  相似文献   
40.
随着整形美容外科专业在我国的蓬勃发展,国内不同等级的医疗机构对经过正规培训的整形美容外科医生的需求逐年在增加。为了提高教学效果,针对整形外科不同层次的学生,我们采用了多种形式、有针对性的教学模式,并取得了一定的效果。本文分别从教学查房、手术带教、读书报告、技能培训、学术交流、专题讲座等多个层面浅析了整形外科临床教学模式。  相似文献   
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