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101.
PSA、SPECT骨显像在前列腺癌诊断和治疗中的临床价值 总被引:1,自引:0,他引:1
目的:探讨PSA、SPECT骨显像在前列腺癌诊断及治疗中的临床应用.方法:对72例经临床确诊的前列腺癌患者全部行血清PSA测定及全身骨显像,并对部分患者治疗后进行了随访.结果:前列腺癌组PSA明显高于正常对照组、良性前列腺疾病组;前列腺癌骨转移组PSA明显高于非骨转移组;72例前列腺癌初诊患者骨显像发现24例骨转移瘤,阳性率33.3%.结论:血清PSA与骨显像联检对前列腺癌临床诊断、疗效观察及预后判定具有重要的指导意义. 相似文献
102.
四引物突变特异性扩增系统法检测巨噬细胞移动抑制因子基因-173位点单核苷酸多态性分布 总被引:1,自引:0,他引:1
目的探讨中国浙江地区汉族人群巨噬细胞移动抑制因子(macmphage migration inhibitory factor,MW)基因-173位点单核苷酸多态性(single nucleotide polymorphism,SNP)分布。方法收集浙江地区142名无血缘关系健康个体的静脉血,提取DNA,分别应用四引物突变特异性扩增系统(amplification refractory mutation sysntem,ARMS)法和限制性片段长度多态性.PCR方法对MIF基因-173位点SNP多态性进行分型,并将PCR产物克隆及测序鉴定。结果MIF基因-173位点检测到3种基因型,其基因型分布皆符合Hardy-Weinberg平衡定律。四引物ARMS法和限制性片段长度多态性-PCR两种方法结果完全一致。统计分析显示,中国汉族人MIF基因-173位点等位基因和基因型频率分布与欧洲白人差异有统计学意义(P〈0.01),与日本人群的差异无统计学意义(P〉0.05)。结论四引物ARMS法是一种准确、快速和经济的SNP测定方法。MIF基因-173位点等位基因频率分布具有种族的差异性。 相似文献
103.
P A Majiwa G Matthyssens R O Williams R Hamers 《Molecular and biochemical parasitology》1985,16(1):97-108
Genes encoding various Trypanosoma (Trypanozoon) brucei variable surface glycoproteins (VSGs) show considerable conservation among different members of this species, known as isotypes. The occurrence of isotypes in other salivarian trypanosomes has not been well documented. We have cloned sequences encoding Trypanosoma (Nannomonas) congolense ILNat 2.1 VSG, and used it in DNA blot hybridization analyses of this and other T. congolense clones originating from geographically separate regions of East Africa. The data indicate that the expression of ILNat 2.1 VSG gene proceeds by duplicative transposition resulting in the presence of an extra expression-linked copy in the expressing clones examined. Furthermore the ILNat 2.1 VSG gene sequence is absent or has greatly diverged, in all other T. (N.) congolense clones that belong to different serodemes. This suggests that some T. (N.) congolense VSGs may be limited to their respective antigen repertoires. The data are discussed in the light of their implications for antigenic variation in T. (N.) congolense, and parasite epidemiology. 相似文献
104.
血管紧张素原基因的六种单核苷酸多态与原发性高血压的相关性 总被引:7,自引:1,他引:7
目的 研究血管紧张素原 (angiotensinogen,AGT)基因 6个位点的单核苷酸多态及其构成的单倍型与中国汉族人原发性高血压的相关性。方法 采用多重SNa Pshot反应 ,在 185例原发性高血压患者和185名健康对照者中 ,对 AGT基因启动子区域的 G- 2 17A、G- 15 2 A、A- 2 0 C、G- 6 A及第 2外显子的T174 M和 M2 35 T多态进行基因分型。结果 6种单核苷酸多态的基因型分布及其等位基因频率在原发性高血压组和对照组中差异无显著性 (P>0 .0 5 )。单倍型分析提示由 - 15 2 A,- 2 0 C,- 6 A和 2 35 T等位基因构成的 H4单倍型在原发性高血压组中明显增加 ,与对照组相比差异有显著性 (P<0 .0 5 )。结论 AGT基因G- 15 2 A,A- 2 0 C,G- 6 A和 M2 35 T多态可能对中国汉族人原发性高血压的发病起了重要作用。 相似文献
105.
目的筛选出抗SARS-CoV病毒N蛋白的单链抗体。方法利用原核表达所获得的SARS病毒N蛋白,筛选人源单链抗体噬菌体展示库,经特异性的检测,以期得到抗SARS-CoV病毒N蛋白的特异单链抗体。结果获得了8个抗SARS病毒N蛋白的候选克隆。经测序,获得了编码抗体可变区的基因序列,并进行了原核表达。结论筛选得到的抗SARS-CoV病毒N蛋白单链抗体具有高度的特异性,可以用作临床实验或研究SARS病毒过程中快速检测SARSN蛋白或SARS病毒粒子的候选抗体。 相似文献
106.
S. Hering D. J. Beech T. B. Bolton S. P. Lim 《Pflügers Archiv : European journal of physiology》1988,411(5):590-592
The actions of nifedipine or BAY K 8644 were studied on barium currents recorded from single, collagenase- and elastase-dispersed, smooth muscle cells from the rabbit ear artery using the whole-cell configuration of the patch-clamp technique. Nifedipine (3M) caused a reduction in the barium current (IBa) evoked by steps to potentials positive of-10mV. This was characterized by a pronounced initial block, an increase in the rate of current decay during the voltage-clamp step, but by no increase in block if pulses were repeated every 600ms. Rapid extracellular application of nifedipine (1M) during the sustained current component (using a new concentration-jump technique) was found to have no effect on IBa over 4s at +20mV, but after returning to the holding potential (-60mV) for 10s, sustained IBa was subsequently abolished. BAY K 8644 (1M) increased IBa at all potentials, and on rapid application during the sustained current component markedly potentiated IBa. The results suggest that nifedipine binds with high affinity to the closed, available state of the Ca++ channels but they do not suggest binding to the open or inactivated states. The effect of BAY K 8644 is consistent with high affinity binding to the open or inactivated and to the closed, available states. 相似文献
107.
目的研究益精养血方对帕金森病(Parkinson's disease,PD)大鼠多巴胺能神经元Caspase-3表达的影响。方法将微量6-羟多巴胺(6-OHDA)立体定向注射于SD大鼠中脑右侧黑质以建立大鼠帕金森病模型,将造模成功的实验动物随机分为模型组、实验(中药)组,每组6只;另纳入6只正常大鼠为正常组。正常组和模型组大鼠生理盐水灌胃,实验组大鼠益精养血方灌胃,各30天。灌胃结束两周后进行行为学检测,免疫组织化学方法观测黑质酪氨酸羟化酶(TH)、Caspase-3的表达。结果实验组大鼠的旋转圈数比治疗前明显减少(P<0.05),实验组损毁侧与健侧黑质TH阳性细胞数量百分比较模型组显著提高(P<0.05),实验组损毁侧黑质Caspase-3表达的OD值比模型组显著降低(P<0.05)。结论益精养血方可使帕金森病大鼠多巴胺能神经元Caspase-3的表达降低,明显抑制神经细胞凋亡。 相似文献
108.
Mutations in the SLC19A2 gene cause thiamine-responsive megaloblastic anemia (TRMA) frequently combined with diabetes mellitus and deafness. Type 2 diabetes mellitus is heritable and a region on 1q21-q23 encompassing SLC19A2 was linked with the disease in Pima Indians and Caucasians. We therefore investigated this candidate gene in selected diabetic and nondiabetic Pimas and found no variants. We conclude that mutations in SLC19A2 do not contribute to type 2 diabetes in this population. 相似文献
109.
A. I. Gorin A. M. Serebryanyi L. V. Antonova V. K. Atkochyunaite I. G. Kharitonenkov N. N. Zoz P. I. Tseitlin 《Bulletin of experimental biology and medicine》1976,81(6):835-838
The effect of solubilization of deoxyribonucleoproteins (DNP) in a medium of near-physiological ionic strength after treatment with the mutagen N-nitroso-N-methylurea (NMU) is highly dependent on the NMU concentration. To convert DNP into a soluble state, the critical number of groups in the DNA and protein must evidently be modified. On the basis of data obtained by the circular dichroism method and by viscosimetry it is concluded that after treatment with NMU the DNP complex becomes soluble in solvents with near-physiological ionic strength largely as a result of labilization and dissociation of the DNA-protein bonds.Laboratory of Biophysics, Institute of Medical Genetics, Academy of Medical Sciences of the USSR. Sector of Kinetics of Chemical and Biological Processes, Institute of Chemical Physics, Academy of Sciences of the USSR. Laboratory of Physical Methods of Investigation, D. I. Ivanovskii Institute of Virology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR S. S Debov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 6, pp. 674–677, June, 1976. 相似文献
110.
G Hagner 《Immunobiology》1984,167(4):389-397
The erythroleukemic K562 cell line was induced to erythroid differentiation by a variety of agents, including hemin, bleomycin, and cytosine arabinoside. The sensitivity of induced cells to binding and lysis by non-sensitized peripheral blood mononuclear cells (MNC) in agarose was studied in relation to the target cell division rate. Differentiated K562 cells formed a lower proportion of conjugates with MNC, when compared with non-induced controls. The reduction correlated significantly with the level of differentiation, irrespective of the inducer and the proliferative status. The differentiation-induced alterations of lysis, however, were strongly influenced by the modification of target cell growth rate which was caused by the differentiating agent. These data suggest that target cell differentiation has distinct effects upon the steps of recognition and lysis by natural killer cells. 相似文献