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551.
552.
中药材苦地胆及其混淆品的DNA指纹鉴定   总被引:10,自引:1,他引:9  
H  Cao  PPH  But  PC  Shaw 《药学学报》1996,31(7):543-553
用聚合酶链式反应方法,包括臆断引物聚合酶链式反应技术和随意引物扩增的多态性DNA技术,鉴定中药材苦地胆及其混淆品,结果表明:用六个长的和一个短的引物扩增的苦地胆及其混淆品基因组DNA指纹和多态性,可在琼脂糖凝胶上明显地区别开来。根据这些指纹图谱及由此估算的相似度值,证实从福建,台湾,香港以及澳门获得的商品药材苦地胆的基原为菊科植物地胆草。  相似文献   
553.
To evaluate its potential for differentiating benign from malignant breast lesions, digital subtraction angiography of the breast (DSAB) was performed in 23 women with mammographic evidence of disease, and the results were compared with surgical biopsy findings. The DSAB technique employed breast immobilization with modest compression and bolus injection; following the injection of contrast material, 30-40 sequential subtraction images were obtained over a 5-minute interval. The average technical settings were 50 k Vp and 10 mAs, resulting in an estimated radiation dose to the breast of 0.05 mrad (0.5 mu Gy) per exposure. DSAB consistently demonstrated retention of contrast material and abnormal vasculature in malignant lesions but not in benign lesions. In the 22 breast lesions for which there was histopathologic correlation, DSAB correctly categorized eight of nine malignant and 11 of 13 benign lesions. Although this series is small, the initial results of DSAB suggest its potential for differentiating benign from malignant lesions.  相似文献   
554.
ABSTRACT. The GnRH analogue Buserelin was given for one year to six girls with central precocious puberty in a daily subcutaneous dose of 20 μg/kg/day. A decrease of plasma estradiol and vaginal maturation index to prepubertal values was obtained in 5 out of 6 cases. Bone maturation decreased and final predicted adult height improved significantly. This analogue of GnRH appears to be an effective medication for gonadotropin dependent precocious puberty in girls.  相似文献   
555.
A B-cell non-Hodgkin's lymphoma (B-NHL) cell line (Karpas 1106) with an unusual three-way translocation involving 18q21.3 has been derived from a patient with mediastinal lymphoblastic B-NHL. Although conventional cytogenetics showed a derivative 18q-identical to that seen in cases with t(14;18)(q32.3;q21.3), no translocations of either chromosome 14 could be detected. Instead fluorescent in situ hybridization analysis using a chromosome-18 paint showed that the segment 18q21.3-18qter had become sandwiched on a derivative chromosome X between segments Xqter-c- Xq28 and 13q12-qter, with the centrometric site of 18q21.3 subband juxtaposed to the X sequences. Pulsed-field DNA blots failed to detect rearrangement of the BCL2 gene. Conventional DNA blots using a variety of restriction digests and both 5' and 3' BCL2 and FVT 1 probes also failed to detect rearrangement in Karpas 1106. A rearranged fragment seen only in HindIII digests with 5' BLC2 probes may represent a local microalteration, which is either a mutation or small deletion involving the HindIII site as seen in other cases of B-NHL. Neither BCL2 RNA nor BCL2 protein expression were detected. These and other data suggest that genes at 18q21.3, other than BCL2 and FVT1, may be targets for translocation in certain subgroups of B-NHL.  相似文献   
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557.
Rapid diagnosis of pancreatic carcinoma   总被引:1,自引:0,他引:1  
Freeny  PC; Ball  TJ 《Radiology》1978,127(3):627
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558.
Activated protein C inhibits platelet prothrombin-converting activity   总被引:12,自引:0,他引:12  
Comp  PC; Esmon  CT 《Blood》1979,54(6):1272-1281
Bovine platelets that have been activated by thrombin facilitate the conversion of prothrombin to thrombin in the presence of calcium ions and factor Xa. Activated protein C, a vitamin-K-dependent plasma protein, inhibits this platelet prothrombin-converting activity. The inhibition is time dependent and is not reversed by increasing concentrations of factor Xa. However, factor Xa is able to protect the platelet prothrombin-converting activity from inactivation by activated protein C. The activated protein C causes a parallel loss of factor Xa receptor sites and platelet prothrombin-converting activity. Activated protein C may contribute to the regulation of clotting through inactivation of the platelet prothrombin-converting activity.  相似文献   
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