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101.
DNA was extracted from an odontogenic keratocyst and assayed for the presence of human papilloma virus (HPV) type 16 DNA sequences using high stringency Southern blot hybridization. HPV type 16 homologous DNA sequences were detected at a copy number of 50-100 genome copies per diploid cell. The oral HPV DNA was not identical to the prototype HPV 16 when cleaved with the restriction enzyme Pst-I, since it appeared to lack the Pst-I C fragment (L2/L1 ORFs) and contained "off-sized" high molecular weight fragments suggestive of integration events into the host cell chromosome. 相似文献
102.
Summary A series of 24 human acoustic neurinomas from 24 patients has been assayed for several biochemical parameters characteristic of the nervous system. S 100 protein, 2, 3-cyclic nucleotide 3-phosphohydrolase activity, and the myelin lipids galactosylceramide and sulfogalactosylceramide (sulfatide). Myelin basic protein was not detected. These findings further support the neuroectodermal origin of the human acoustic neurinoma, and provide additional biochemical markers for further study. 相似文献
103.
P C Leung 《The Journal of hand surgery》1979,4(5):409-411
Venous congestion in a replanted or transplanted digit can be detected, even before any obvious color changes, by the "throbbing" elicited by pinching the digit between the thumb and finger of the examiner until the skin blanches. Releasing the pressure slowly, a sensation of throbbing will be felt synchronous with the patient's pulse rate. The sign disappears when venous congestion is relieved or when swelling persists and increases enough to lessen the arterial inflow. 相似文献
104.
Vascular access through subcutaneous prosthetic arteriovenous fistulas was studied in eighteen dogs. Dacron velour and woven Dacron grafts (6 mm diameter) were constructed across the lower abdomen between the common femoral artery and the opposite common femoral vein. In heparinized animals 197 percutaneous punctures were made with a "14 guage hemodialysis cannula at weekly intervals. Over a period of one and a half years there was no instance of infection. One of the fourteen Dacron velous and all four woven Dacron fistulas thrombosed. These data suggested the feasibility of achieving repetitive blood access through Dacron velour vascular prostheses. Nineteen Dacron velour fistula bypasses between the brachial artery and median basilic vein were performed in fifteen selected patients for a total dialysis period of ninety-six months. Failed standard subcutaneous fistulas or absence of suitable vessels in the upper extremity were indications for the primary procedure. Of three looped forearm fistulas, two thrombosed at twenty-two and two months. Complications among sixteen straight bypasses in the arm included two graft infections and one cannula tract infection. There were no instances of thrombosis in this group. The advantages of single needle dialysis in these high risk patients have been emphasized. Eleven grafts are presently functioning two to nine months postoperatively. Our preliminary results suggest that a Dacron velour fistula merits consideration as an alternative for vascular access in maintenance hemodialysis. 相似文献
105.
Monory K Bourin MC Spetea M Tömböly C Tóth G Matthes HW Kieffer BL Hanoune J Borsodi A 《The European journal of neuroscience》2000,12(2):577-584
The recently discovered endomorphin 1 (Tyr-Pro-Trp-Phe-NH2) and endomorphin 2 (Tyr-Pro-Phe-Phe-NH2) were investigated with respect to their direct receptor-binding properties, and to their ability to activate G proteins and to inhibit adenylyl cyclase in both cellular and animal models. Both tetrapeptides activated G proteins and inhibited adenylyl cyclase activity in membrane preparations from cells stably expressing the mu opioid receptor, an effect reversed by the mu receptor antagonist CTAP (D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2), but they had no influence on cells stably expressing the delta opioid receptor. To further establish the selectivity of these peptides for the mu opioid receptor, brain preparations of mice lacking the mu opioid receptor gene were used to study their binding and signalling properties. Endomorphin 2, tritiated by a dehalotritiation method resulting in a specific radioactivity of 1.98 TBq/mmol (53.4 Ci/mmol), labelled the brain membranes of wild-type mice with a Kd value of 1.77 nM and a Bmax of 63.33 fmol/mg protein. In membranes of mice lacking the mu receptor gene, no binding was observed, and both endomorphins failed to stimulate [35S]guanosine-5'-O-(3-thio)triphosphate ([35S]GTPgammaS) binding and to inhibit adenylyl cyclase. These data show that endomorphins are capable of activating G proteins and inhibiting adenylyl cyclase activity, and all these effects are mediated by the mu opioid receptors. 相似文献
106.
DNA测序建立甘肃当归、大黄种子rRNA基因图谱的研究 总被引:3,自引:0,他引:3
目的:对甘肃地道性中药材当归、大黄种子中rRNA基因内转录间隔区进行碱基序列测定,以期建立从分子水平对中草药种子进行鉴定的一种新方法。方法:提取当归、大黄种子中核DNA,利用特异性引物对其rRNA基因内转录间隔区进行套式PCR扩增,并将扩增产物进行碱基序列测定。结果:经琼脂糖凝胶电泳证实:以上述方法可获得当归、大黄种子DNA中rRNA基因内转录间隔区PCR扩增产物;并经测序后得到了当归、大黄种子rRNA基因内转录间隔区的碱基序列,且具有明显的差异和可对比性。结论:不同植物性中药材种子rRNA基因内转录间隔区碱基序列可做为从分子水平进行鉴定的标记。 相似文献
107.
目的 研究nm2 3和c -erbB - 2蛋白在子宫内膜癌中的表达及其临床意义。方法 用LSAB免疫组化法检测 4 2例子宫内膜癌中nm2 3和c -erbB - 2蛋白的表达。结果 nm2 3和c -erbB - 2在子宫内膜癌中的阳性表达率分别为 6 0 0 %、 4 7 6 % ,其阳性表达与年龄、不同组织学类型差异无显著 (P >0 0 5 ) ;nm2 3与病理分级呈负相关 (P <0 0 1 ) ,无淋巴结转移者阳性表达率明显高于淋巴结转移者 (71 9%和 2 0 0 % ,P <0 0 5 ) ;c -erbB - 2的表达与癌细胞的分化程度、临床分期有关 ,分化程度高及早期癌中c -erbB - 2表达强。结论 对子宫内膜癌组织进行nm2 3和c -erbB - 2蛋白的检测 ,有助于了解子宫内膜癌的临床病理特征和预后 相似文献
108.
子宫内膜癌中p16、E-cad mRNA表达的研究 总被引:1,自引:0,他引:1
目的 :探讨p16及E 钙粘附蛋白 (E cad)基因mRNA在子宫内膜癌中的表达及意义。方法 :采用RT PCR技术检测 3 0例子宫内膜癌及 8例正常子宫内膜组织的p16及E cadmRNA的表达。结果 :①子宫内膜癌p16mRNA的阳性表达明显低于正常子宫内膜 (P <0 .0 1) ,但p16mRNA的表达与子宫内膜癌的组织病理分级无关 ;②E cadmRNA在子宫内膜癌中呈低表达 ,正常组织内呈强阳性表达 ,二者差异非常显著 (P <0 .0 1) ,并且在子宫内膜癌中E cadmRNA的阳性表达与组织病理学分级呈负相关 (P <0 .0 5 )。结论 :p16、E cadmRNA的表达在子宫内膜癌的发生及进展过程中起重要作用 相似文献
109.
野生型P53、P16基因联合抑制人胃癌细胞HGC27生长的实验研究 总被引:1,自引:0,他引:1
背景与目的:探讨逆转录病毒介导的野生型P53、P16基因协同抑制人胃癌细胞生长的作用.材料与方法:用脂质体转染法将携有野生型P53基因、P16基因的逆转录病毒载体pLNCX,转染人未分化胃癌细胞系HGC27,对转染后细胞进行生长曲线、MTI生长抑制率、Southern杂交、流式细胞术分析,观察其生物学特性变化.结果:野生型P53、P16蛋白的过表达对胃癌细胞系均呈现出生长抑制作用;野生型P53基因与P16基因联合导入HGC27细胞,对细胞生长抑制、促使凋亡效果高于单种基因转染.结论:野生型P53、P16基因联合治疗效果高于利用个别基因的治疗效果. 相似文献
110.
对西京医院进行根治性放疗的食管鳞状细胞癌患者 64例 ,照射剂量DT64~ 70Gy ,进行前瞻性研究 ,对其治疗前活检标本进行SP免疫组化染色 ,计数其阳性细胞数 ,并计算阳性率 ,观察其阳性率与食管癌放疗疗效及预后的关系。结果PCNA阳性率 5 1%~ 67 1% ,中央值 3 2 0 % ,PCNA阳性率 >40 %者较低于此值者预后明显差。p16在低分化癌中较高分化癌阳性表达率低 ,且随着病期的进展阳性表达率降低 ,P <0 0 5 ;Ki 67与近期疗效及预后未见明显差异。初步研究结果提示 ,PCNA阳性率是判断放疗疗效有意义的指标 ,且与p16联合检测对食管鳞癌放疗前恶性程度评定和预后估计有重要意义 相似文献