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111.
苦绳的甾体成分 总被引:3,自引:0,他引:3
从苦绳(Dregea sinensis Hemsl.)中分离到两个新化合物∶苦绳甙元乙(dresigeninB,1)和苦绳甙I(dresiosideI,2)。经光谱和化学反应确定其结构为∶20-O-(2-甲基丁酰基) 托曼托甙元[20-O-(2-methylbutyryl)-tomentogenin]和二氢肉珊瑚甙元3-O-β-D-吡喃黄夹糖基(1-4)-β-D-吡喃夹竹桃糖基(1-4)-β-D-吡喃磁麻糖甙[dihydrosarcostin 3-O-β-D-thevetopyranosyl(1-4)-β-D-oleandropyranosyl(1-4)-β-D-cymaropyranoside]。 相似文献
112.
犬冠状动脉定量狭窄造成急性心肌缺血,观察巴曲酶(batroxobin)对冠脉循环及血流动力学的影响。结果显示,batroxobin可剂量依赖性地增加缺血心脏冠脉血流量,2BU·kg-1(0.1BU·kg-1·min-1)iv后40min,缺血犬冠脉流量比盐水对照组增加12%,此时小冠脉阻力由4.1±0.5降至3.2±0.5mmHg·min·ml-1,而大冠脉阻力无明显变化;给药后120min,上述作用仍然持续,且冠脉总阻力降低13%,左室压上升及下降最大速率与盐水对照组相比分别增大14%和16%。结果表明,batroXobin在冠脉低灌流状态下仍可降低小冠脉阻力,增加冠脉流量,这可能是其改善缺血犬冠状循环及心脏功能的机理之一。 相似文献
113.
David J Stewart Milam Leavens Katherine Lu YM Wang Robert S Benjamin Dah Hsi Ho Hwee Yong Yap Ti Li Loo 《Journal of neuro-oncology》1984,2(3):187-193
Radiolabelled Baker's Antifolate (BAF) was administered to 6 patients undergoing surgical resection of intracerebral tumors. Levels of radioactivity in resected tumor and edematous brain adjacent to tumor were generally higher than levels in concurrent plasma samples and were generally comparable to levels in temporalis muscle. Levels in tumor cyst fluid were far lower than concurrent plasma levels and levels in surrounding tumor. Chromatography was performed on tumor from 2 patients and revealed that only a small proportion of the radioactivity represented unchanged BAF. The major metabolite present in tissues was 1 000 times less potent as an inhibitor of dihydrofolate reductase than was BAF.Five patients had cerebrospinal fluid (CSF) sampled following administration of tracer doses of radio-labelled BAF. Radioactivity levels were far lower in CSF than in plasma. Levels of radioactivity in the CSF were also far lower than levels in tumor and brain samples from other patients and were slightly lower than tumor cyst fluid levels. Two patients had CSF collected after they received therapeutic doses of BAF. In these patients, both CSF and plasma were assayed using a dihydrofolate reductase inhibition assay. As with tracer dose studies, CSF concentrations of BAF were substantially lower than were concurrent plasma concentrations.Thus it appears that only very low concentrations of BAF are attainable in human CSF and intracerebral tumor, although a metabolite which is a very weak inhibitor of dihydrofolate reductase attains high concentrations in tumor.The abbreviations used are: BAF
Baker's Antifolate
- CNS
Central Nervous System
- CSF
Cerebrospinal Fluid
Supported by grant number CA-14528 and Contract CM-53773 from the National Cancer Institute. Presented in part at the 70th annual meeting of the American Association for Cancer Research, New Orleans, Louisiana, May, 1979. 相似文献
114.
Hepatic micrometastases in the rat: ferrite-enhanced MR imaging 总被引:3,自引:0,他引:3
A rat tumor model was used to evaluate the ability of ferrite-enhanced magnetic resonance (MR) imaging to demonstrate hepatic metastases smaller than 1 cm. Twenty-eight rat livers were inoculated with 5 X 10(5) mammary carcinoma cells and imaged with a 0.6-T MR system. Non-enhanced and ferrite-enhanced images were analyzed and correlated with autopsy findings for each rat. Lesion detection rates correlated closely with cancer-to-liver contrast-to-noise ratios. Ferrite-enhanced MR imaging demonstrated significantly more lesions than non-enhanced imaging (P less than .05) and decreased the threshold size for lesion detectability (less than 2 mm). Ferrite also enabled more accurate measurements of the lesions (r = .96). 相似文献
115.
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117.
防治成人呼吸窘迫综合征的人工重组肺泡表面活性剂研制III.模型动物预防试验 总被引:1,自引:1,他引:0
人工重组肺泡表面活性剂(APS)是基于成人呼吸窘迫综合征(ARDS)发病中存在的肺泡表面活性剂缺乏和过量自由基引起肺损伤两种主要发病因素设计研制的。内毒素致ARDS大鼠的预防给药试验结果表明,APS能显著降低动物死亡率(46.47%→16.17%)和肺水肿程度(W/D从5.55→4.84)。同时,肺灌洗液的表面性能也有明显改善(平衡表面张力从61.86→47.02mN·m-1,正常43.94mN·m-1;最小表面张力从30.41→7.16mN·m-1,正常3.49mN·m-1)。动物初步预防试验的结果支持ARDS防治药物设计依据。 相似文献
118.
A new imaging format described here uses nonplanar reformations that follow the contour of curved structures intersected by a series of regularly spaced CT scans. The CT scanning procedure is described, and algorithmic details of this new format are presented. A standard set of reformatted images is suggested, and clinical examples are given to illustrate the diagnostic value of this new format. 相似文献
119.
Luciano Bovicelli Nicola Rizzo Luigi Fiuppo Orsini Laura Michelacci 《Clinical genetics》1980,18(1):79-82
A male fetus with prune belly syndrome was diagnosed by ultrasound at 30 weeks of gestation. The diagnosis was confirmed after birth. 相似文献
120.
纳米羟基磷灰石沉积层/钛酸钾薄层/钛合金生物复合材料体外培养成骨细胞的研究 总被引:1,自引:1,他引:1
在制备出具有表面活性的纳米羟基磷灰石沉积层/钛酸钾薄层/钛合金(HA/K2Ti6O13/β-Ti)生物复合材料的基础上,将体外培养的成骨细胞与HA/K2Ti6O13/β-Ti生物复合材料、未经处理β钛合金两种骨替代材料共同培养,在既定时间内观察两种骨替代材料对成骨细胞生长、附着的影响。结果表明两种骨替代材料对成骨细胞生长无明显抑制或促进作用,均具有良好的细胞相容性,它们皆能使成骨细胞附着于各自材料表面,分泌形成胶原纤维样基质。HA/K2Ti6O13/β-Ti生物复合材料较β钛合金具有更优异的的生物活性和成骨性能,是一种很好的生物植入材料。 相似文献