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21.
22.
以聚合酶链反应(PCR)法在mRNA水平检测T淋巴细胞受体α链可变区基因表达为例,介绍用~(32)P标记的人工合成寡核苷酸探针对PCR产物特异性作阳性证实的方法。该法以干琼脂糖凝胶作为支持物、相对较为简便和省财。用Ca探针以干凝胶作支持物的杂交结果,证实29个Vα基因的PCR扩增中物均为特异性的,放射自显影的带型与位置和溴乙锭染色所示完全吻合。 相似文献
23.
目的对FKBP6基因第3、4外显子进行突变和多态性筛查,研究第3外显子278C/A位点及第2内含子C/T位点(rs7797242)在无精症患者和正常男性中的多态性,初步探讨与原发无精症的相关性。方法采用变性高效液相色谱和聚合酶链反应-限制性片段长度多态性方法,对第3、4外显子进行突变和多态性筛查,对177例无精症患者和231名正常男性的278C/A和C/T(rs7797242)多态性进行基因分型。结果278C和278A等位基因频率符合Hardy-Weinberg平衡。无精症患者278A显著低于正常对照,差异有统计学意义(P<0.05)。C/T多态性在两组中均未检出,第3、4外显子未筛查到新的变异。结论278A等位基因可能与原发无精症相关。C/T(rs7797242)及370G/A,430G/C,467T/C,468G/A在中国人群中非常罕见。 相似文献
24.
目的:分析实行医保单病种后医保病人与非医保病人阑尾炎治疗的费用差距,提出对医保进一步改革的思索。方法:用Excel 2003建数据表,对我院2005年2月至2006年8月期间收治的单病种收费阑尾炎患者和非单病种收费患者的费用和并发症进行分析并进行统计学处理。结果:阑尾炎治疗并发症发生率及痊愈率在两组间无显著性差异,费用比较两组间差异显著。结论:目前的单病种收费标准基本可以满足临床治疗阑尾炎的需要,同时在实行单病种收费后可以节约大量医疗费用。如进一步扩大单病种范围,用经济手段调动医院的自律机制,医疗费用有进一步下降的空间。 相似文献
25.
U. Yinon S. Gelerstein 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,87(1):181-192
Summary The visual cortex of adult cats was studied physiologically following neonatal isochronic transplantation of grafts from areas 17,18, which were placed homotopically, in order to reveal their functional integration and thus possible repairing of damaged cortical neuronal circuits. Three homograft cats, in which transplantation was carried out between siblings (228 cortical cells) were compared to 4 animals receiving reimplanted autografts of the equivalent size (131 cells) as well as 3 animals with analogous sectioning of the visual cortex (162 cells) (pseudograft controls). The location of the boundaries between the transplant region and the host were determined using the Nissl's method for staining histological cross sections. Extracellular unit recording revealed typical waveform of the action potentials in the transplanted region and in the surrounding host tissue of all groups of cats. Visual responsiveness in the homograft cats was 17.5% in the transplanted region and 80.4% in the unoperated hemisphere; the corresponding results were 40.3% for the transplanted region and 82.2% for the unoperated hemisphere in the autografts and 23.1% and 73.4% in the pseudografts. The specificity of the cells to visual stimulation as expressed by their orientation and direction specificity, indicated preservation of these properties in the transplanted cats. While all responsive cells in the transplanted region of the homografts were orientation specific, their proportion was 60% in the autografts and 55.5% in the analogous region in the pseudograft controls. As to the direction specific cells, their performance in the grafted region of the grafted cats was even much higher than that of the pseudograft controls. The ocular dominance distribution of the cells showed preservation of binocularity in the transplanted region (90.0% binocular cells) of the homografts; it was however smaller in the equivalent region of the autografts (65.0%) and remarkably reduced (20.0%) in the pseudografts. It was concluded that despite the deafferentation induced during the transplantation procedure, a remarkable visual responsiveness was found in the transplanted region, indicating postoperative recovery. However, the cells there were mainly affected in their activity and less in their specificity to visual stimulation. 相似文献
26.
我国登革2型病毒43株包膜E蛋白基因的特征 总被引:2,自引:0,他引:2
对我国1987年流行的登革2型病毒43株包膜E蛋白基因的核苷酸序列进行了分析。结果表明登革2型病毒43株包膜E蛋白基因核苷酸序列含1485个核苷酸,编码495个氨基酸,并就其核苷酸序列及其相应的氨基酸序列与其它的登革2型病毒株进行了比较,发现核苷酸序列与我国1985年分离的登革2型病毒04株,新几内亚C株(NGC),牙买加株1409(JAM)和马来西亚当地流行株M1(登革出血热)、血2(登革休克综合征)、M3(登革热)同源性分别是95.8%、94.6%、97.5%、925%、92.7%和939%,氨基酸序列的同源性分别是94.3%、94.3%、96.0%、93.7%、93.7%和91.5%,推断出的氨基酸序列显示出12个保守的半胱氨酸残基和两个潜在的糖基化位点,分别位于Asn-67和Asn-153位。 相似文献
27.
多抗甲素对人NK细胞活性的作用机理研究 总被引:1,自引:0,他引:1
作者应用单细胞细胞毒试验及形态学观察,研究多抗甲素(PAA)对人体自然杀伤(NK)细胞活性的作用机理。结果表明:PAA能增强食道癌患者淋巴细胞(PBL)明显低下的结合率(B%)和杀伤率(K%),也可增强正常人PBL的K%,但对正常人PBL的B%无影响。形态学观察发现:与靶细胞结合的PBL除大颗粒PBL外,尚有普通的非颗粒PBL,结合的靶细胞损伤首先表现为线粒体肿胀、空泡变,然后核固缩,核膜损伤,细胞严重空泡变性等,偶见靶细胞与自然杀伤细胞结合部质膜破损的现象。经PAA预处理的靶效细胞结合的形态改变无明显差异,但食道癌组的杀伤作用出现较早,且明显增强。 相似文献
28.
P. Apicella Eric Legallet Elisabeth Trouche 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,116(3):456-466
In the primate striatum, the tonically discharging neurons respond to conditioned stimuli associated with reward. We investigated
whether these neurons respond to the reward itself and how changes in the behavioral context in which the reward is delivered
might influence their responsiveness. A total of 286 neurons in the caudate nucleus and putamen were studied in two awake
macaque monkeys while liquid reward was delivered in three behavioral situations: (1) an instrumental task, in which reward
was delivered upon execution of a visually triggered arm movement; (2) a classically conditioned task, in which reward was
delivered 1 s after a visual signal; (3) a free reward situation, in which reward was delivered at irregular time intervals
outside of any conditioning task. The monkeys′ uncertainty about the time at which reward will be delivered was assessed by
monitoring their mouth movements. A larger proportion of neurons responsive to reward was observed in the free reward situation
(86%) than in the classically conditioned (57%) and instrumental tasks (37%). Among the neurons tested in all situations (n = 78), 24% responded to reward regardless of the situation and 65% in only one or two situations. Responses selective for
one particular situation occurred exclusively in the free reward situation. When the reward was delivered immediately after
the visual signal in the classically conditioned task, most of the neurons reduced or completely lost their responses to reward,
and other neurons remained responsive. Conversely, neuronal responses invariably persisted when reward was delivered later
than 1 s after the visual signal. This is the first report that tonic striatal neurons might display responses directly to
primary rewards. The neuronal responses were strongly influenced by the behavioral context in which the animals received the
reward. An important factor appears to be the timing of reward. These neurons might therefore contribute to a general aspect
of behavioral reactivity of the subject to relevant stimuli.
Received: 16 September 1996 / Accepted: 1 April 1997 相似文献
29.
应用单向免疫扩散法测定了流行性出血热(EHF)患者的7种补体成份和血浆素原(Pg).结果表明,CT脂酶抑制剂在少尿期、多尿期和恢复期均高于正常(P<0.01);补体C_1q在多尿期高于正常(P<0.01);补体C_4在发热期和少尿期低于正常(P<0.01),以后逐渐恢复正常;补体C_3,C_5和C_9的变化与C_4相似;B因子在少尿期低于正常(P<0.01),在多尿期高于正常(P<0.05);Pg始终高于正常水平但在少尿期有回降.说明EHF患者不仅有补体经典途径的识别阶段、活化阶段和膜攻击阶段的变化,而且亦有旁路激活,其活化程度与病情有关. 相似文献
30.
H. S. Markus C. B. Bunker K. Kouris D. C. Costa M. J. Harrison 《Journal of neurology》1992,239(7):363-366
Summary Conventional imaging with computed tomography (CT) and magnetic resonance imaging (MRI) may show abnormalities in central nervous system Behcet's syndrome but is normal in some cases. Recently in two cases positron emission tomography has shown abnormalities in blood flow and glucose metabolism far more extensive than the abnormalities seen on CT and MRI scans in the same patients. We report a patient with neuro-Behcet's syndrome presenting with headache and personality change in whom CT and MRI brain imaging was normal, but regional cerebral blood flow imaging using single photon emission tomography with the tracer HMPAO showed extensive perfusion deficits which partially reversed after 3 months of prednisolone therapy. This technique may aid the diagnosis of cerebral involvement in Behcet's syndrome, although the cause and incidence of the perfusion deficits need further evaluation. 相似文献