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排序方式: 共有8482条查询结果,搜索用时 15 毫秒
1.
目的 建立蒙药绿松石的质量标准。方法 收集不同产地绿松石,共10批。观察绿松石样品和粉末的性状并进行理化鉴别;按2020年版《中国药典》(四部)通则方法测定绿松石样品中水分、浸出物含量;采用原子吸收光谱法测定绿松石样品铜元素含量。结果 绿松石为不规则、周围带有黑石的块状物,表面蓝绿色,体重,质硬脆,难砸碎,断面呈贝壳状,蜡样光泽,粉末呈灰绿色,无臭,味淡;理化鉴别结果显示,呈铜盐反应;10批次样品中水分含量为0.41%-3.94%(SD=1.37%),浸出物含量为0.21%-0.81%(SD=0.21%),铜元素含量为3.03%-4.63%(SD=0.63%)。结论 初步拟定绿松石中水分含量不得超多5.0%、浸出物含量不得低于0.10%,铜元素含量应为2.60%-4.84%,制定的标准可用于蒙药材绿松石的质量控制。 相似文献
2.
Manuel Steiner Andishe Attarbaschi Margit K nig Helmut Gadner Oskar A. Haas Georg Mann 《Pediatric hematology and oncology》2004,22(1):11-16
Constitutional trisomy 21 is the most prominent predisposing factor to childhood leukemia, whereas the t(12;21)(p13;q22) with its molecular genetic counterpart, the TEL/AML1 fusion gene, is the most common acquired chromosomal rearrangement in childhood B-cell precursor (BCP) acute lymphoblastic leukemia (ALL). Thus, it was somewhat surprising that according to the currently available literature the incidence of TEL/AML1+ BCP ALL is extremely low in patients with Down syndrome (DS). To further investigate this issue in a population-based fashion, the authors retrospectively assessed the number of DS patients with a TEL/AML1+ ALL in two consecutive Austrian ALL multicenter trials. Accordingly, they were able to analyze 8 of 10 individuals with DS and a BCP ALL, including 2 who suffered from a TEL/AML1+ leukemia. Based on this observation we concluded that individuals with a constitutional trisomy 21 may have the similar likelihood to develop a TEL/AML1+ leukemia as BCP ALL patients without this specific predisposing factor. 相似文献
3.
目的 观察优克龙 (Urocalun )治疗输尿管结石的疗效和安全性。 方法 对 6 0例输尿管结石直径 <1cm的患者予口服优克龙治疗 ,4 5 0mg/次 ,3次 /d ,服药 5周。 结果 6 0例患者中结石排出 4 5例 (75 % ) ;10例 (17% )结石位置下降 ;5例 (8% )位置无变化。 4例患者服药后有轻度胃部不适、恶心或口干。 结论 优克龙治疗输尿管结石效果良好。 相似文献
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Dose-response curves of angiotensin I (AI, 1.0-1000.0 pmol) and angiotensin II (AII, 1.25-1250.00 pmol) were obtained in isolated rat hearts subjected to control conditions, mild hypoxia (PO2 = 145 mm Hg), reoxygenation, ischemic (perfusion pressure = 35 mm Hg) and reperfusion. Both AI and AII caused dose-dependent coronary flow (CF) of 26 +/- 3 and 27 +/- 2%, respectively. The effects of both AI and AII were substantially attenuated during hypoxia, but were fully restored upon reoxygenation. During ischemia, the effect of AII was unaltered while the effect of AI was enhanced compared to the control (P less than 0.05). This enhancement was reversible on reperfusion. Cardiac conversion of AI, calculated from ED50 values for AI and AII, was significantly increased during ischemia (P less than 0.05). Infusion of saralasin (0.5-5.0 micrograms/min) did not increase CF in any of the groups. We conclude that (1) the coronary vasoconstrictive effect of AII is preserved in ischemia but attenuated in hypoxia and (2) cardiac conversion of AI to AII is enhanced in hearts injured by ischemia. 相似文献
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Heparin-induced thrombocytopenia (HIT) represents a serious side effect caused by an atypical immune response to platelet factor 4 leading to platelet activation and thrombin formation. These patients are at high risk of thromboembolism, with a rapid drop in platelet count between days 5 and 14 after the initiation of heparin treatment. In single cases, especially after major surgery, platelet count reduction might be absent or hidden by preceding thrombocytosis. Different clinical manifestations of HIT include unspecific skin reactions with potential necrosis at the site of heparin injection, mostly after the application of unfractionated heparin but also with low molecular weight heparin. In heparin-induced skin necrosis, administration of unfractionated or low molecular weight heparin is contraindicated and heparin therapy should be stopped immediately. Instead, an alternative anticoagulant in the form of a direct thrombin inhibitor such as argatroban, and respectively lepirudin, or danaparoid sodium must be administered. Due to frequent misinterpretations of heparin-induced unspecific skin reactions, especially in the absence of thrombocytopenia, we present two case reports which should increase the awareness of HIT’s various clinical pictures. 相似文献
10.
S. Bereswill F. Fassbinder C. Völzing A. Covacci R. Haas M. Kist 《Medical microbiology and immunology》1998,186(4):177-187
Various strains of Helicobacter pylori were able to lyse erythrocytes from sheep, horse, and human when grown on blood agar. The hemolysis did not depend on the
production of the vacuolating cytotoxin VacA as demonstrated by the hemolytic behavior of an isogenic vacA-negative mutant strain. The hemolytic activity could be detected in cell-free supernatants and was not regulated by iron.
To isolate genes coding for proteins involved in the destruction of erythrocytes, a plasmid-based DNA library was screened
for expression of lytic activity on blood agar. This approach revealed that the H. pylori ribA gene confers hemolytic properties to Escherichia coli. The ribA gene encodes the enzyme GTP-cyclohydrolase II [EC 3.5.4.25] that catalyzes the initial step in the synthesis of riboflavin.
The predicted amino acid sequence of the H. pylori RibA protein showed a high degree of similarity to equivalent enzymes from microorganisms and from plants. The single gene
on a plasmid restored riboflavin synthesis in a ribA mutant of E. coli and induced hemolytic activity. Furthermore, ribA overexpression was associated with the production of a fluorescent yellow molecule that was not identical with riboflavin.
Hemolysis was also seen for the ribA gene from E. coli, indicating that this feature was not specific for the H. pylori gene. The presence of ribA in various H. pylori strains was confirmed by Southern blot hybridization and by polymerase chain reaction with specific primers. This analysis
revealed that microdiversity exists within the DNA region upstream from ribA, which was further confirmed by nucleotide sequence analysis.
Received: 25 July 1997 相似文献