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排序方式: 共有540条查询结果,搜索用时 15 毫秒
21.
目的:应用组织多普勒显像(TDI)技术评价卡维地洛对高血压患者左室舒张功能的影响.方法:对30例高血压给予卡维地洛治疗24周.治疗前、治疗后12周、24周用TDI技术测量左室收缩期二尖瓣环平均舒张早期运动速度(Ea)、舒张晚期运动速度(Aa)及Ea/Aa,并与血流多普勒指标E波速度(E)、A波速度(A)、E/A进行比较,观察降压效果及对左室舒张功能的影响.结果:卡维地洛治疗12周后收缩压(SBP)、舒张压(DBP)、心率(HR)均较治疗前下降(P<0.05),Ea、Ea/Aa均较治疗前升高(P<0.05),治疗24周后E、E/A较治疗前升高(P<0.05),Aa较治疗前降低(P<0.05),Ea、Ea/Aa有进一步改善的趋势(P<0.05).结论:TDI技术在评价左室舒张功能方面较二尖瓣血流频谱更敏感;卡维地洛对轻、中度高血压具有良好的降压作用,且能改善患者左室舒张功能. 相似文献
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W Kreis T M Woodcock M B Meyers L A Carlevarini I H Krakoff 《Cancer treatment reports》1977,61(4):723-726
Enzymatic and clinical pharmacologic studies indicate that 2,2'-anhydro-1-beta-D-arabinofuranosyl-5-fluorocytosine (AAFC) is relatively resistant to enzymatic deamination and is not phosphorylated but slowly releases 1-beta-D-arabinofuranosyl-5-fluorocytosine. The latter is deaminated rapidly to 1-beta-D-arabinofuranosyl-5-fluorouracil. After iv injection of labeled cytosine arabinoside (Ara-C), 2,2'-anhydro-1-beta-D-arabinofuranosylcytosine, and AAFC into patients, radioactivity appears in substantial amounts and persists for a prolonged time in the saliva. AAFC slowly penetrates into the cerebrospinal fluid, reaches significant levels, and is retained there for a long time. Ara-C, due to rapid deamination in plasma, does not provide sustained levels of Ara-C in the cerebrospinal fluid. It is likely that this difference between AAFC and Ara-C is due to reduced polarity of the former compound. 相似文献
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Dichloro-1,2-diaminocyclohexane (DACH):platinum(II), the prototype DACH:platinum complex, had good antitumor activity, was not cross-resistant with cis-dichlorodiammineplatinum(II) (DDP), but was, unfortunately, virtually insoluble in water and was, therefore, not evaluated clinically. This paper summarizes some of the chemical and biological attributes of a series of cis-bisascorbato-DACH:platinum(II) complexes (DAP). Although the primary emphasis has been placed on the DAP complex consisting of the isomeric mixture DACH, a series of complexes using the isomers of either DACH or ascorbic acid have also been synthesized. The synthetic procedure entailed reacting the water-soluble sulfato-DACH:platinum(II) with barium ascorbate, and the water-soluble product DAP was removed from the BaSO4 precipitate by filtration. Based upon elemental analysis, all the complexes had stoichiometric composition of one DACH:one platinum and two ascorbate monoanions. High-pressure liquid chromatography of cis-bisascorbato (mixed-isomer DACH):platinum revealed a series of platinum-containing, ultraviolet-absorbing peaks. All the DAP complexes had significant in vitro cytotoxicity against L1210 leukemia cells (L1210/0) with 50%-inhibitory dose values ranging from 2 to 5 micrograms/ml. None of the complexes was cross-resistant with DDP when tested in vitro against L1210 cells 50-fold resistant to DDP (L1210/DDP). The cis-bisascorbato (mixed-isomer DACH):platinum (DAP-1) was administered i.p. to C57BL X DBA/2 F1 mice inoculated i.p. with 10(6) L1210/0 cells. When administered on Days 1, 5, and 9, the DAP-1 complex consistently produced treated:control values in excess of 200% with several long-term survivors (alive 60 days after tumor inoculation). Further, the DAP-1 complex was totally non-cross-resistant with DDP when tested in vivo against a DDP-resistant L1210 line. Toxicological investigations revealed that DAP-1 was relatively nonnephrotoxic but did cause the expected bone marrow and gastrointestinal toxicity. In summary, the DAP complexes are highly water-soluble, nonnephrotoxic platinum complexes with sufficient antitumor activity to warrant further pharmacological, biochemical, and chemical investigations. 相似文献
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Measurement of plasma renin substrate by radioimmunoassay of angiotensin. I. Concentration in syndromes associated with steroid excess 总被引:3,自引:0,他引:3
L R Krakoff 《The Journal of clinical endocrinology and metabolism》1973,37(1):110-117
Plasma renin substrate (PRS) and plasma renin activity (PRA) were measured by radioimmunoassay of generated angiotension I in normal subjects and patients with steroid excess syndromes. In subjects with Cushing's syndrome, glucocorticosteroid therapy and oral contraceptive agents or estrogens, significant elevations of plasma renin substrate was observed. Only in subjects with primary aldosteronism was the plasma renin activity significantly supressed. The significance of elevations of PRS was assessed by determining the Km of the plasma renin-substrate reaction at physiologic pH. The apparent Km for the reaction was 1000 ng Angiotension I in PRS units. Correction of measured PRA to a standardized PRA was achieved by calculation of the reaction rate that would occur at the mean normal PRS concentration of 1100 ng/ml. Results indicate that elevations of PRS which occur in Cushing's syndrome or with administration of glucocorticoids, oral contraceptive agents, or estrogens are sufficient to significantly elevate the renin substrate reaction in plasma. In contrast, glucocorticoid excess appears not to suppress plasma renin activity even when reaction rates are corrected for increased PRS. 相似文献
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Gallium-67 uptake was noted in the mid-pelvic uterine area of a 19-week-pregnant female. Lateral and oblique Ga-67 scans revealed an anterior location of radioactivity that correlated with the position of the placenta as determined by ultrasonic technique. 相似文献