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61.
Expression of the immediate early gene zif/268 (also termed NGFI-A, Krox 24, TIS8 and Egr-1) was investigated in awake rats following various long-term potentiation (LTP) induction protocols.zif/268 mRNA (Northern blots) and protein (immunohistochemistry) levels sharply increased following LTP, and followed a time course characteristic of other immediate early genes. When measured across 3 tetanization protocols known to produce differing degrees of LTP persistence,zif/268 induction was found to be more highly correlated with LTP duration than with the magnitude of initial LTP. These data support the hypothesis that the immediate early gene zif/268 plays a role as a third messenger in the cascade of cellular and nuclear events that govern the persistence of LTP.  相似文献   
62.
应用聚合酶链式反应快速检测嗜肺军团杆菌   总被引:1,自引:1,他引:0  
嗜肺军团杆菌(LP)所引起的肺炎病死率高,易暴发流行,早期病原诊断困难。本研究应用聚合酶链式反应技术对嗜肺军团杆菌血清1、3、5型中巨噬细胞感染潜能基因(mip基因)的部分编码区域进行特异性扩增,经琼脂糖凝胶电泳、溴乙锭染色检测扩增产物。结果3型LP均出现650bp特异性阳性条带。检测灵敏度为80ng,本研究结果对嗜肺军团杆菌肺炎的早期诊断、及时治疗、降低病死率及控制暴发流行有重要意义。  相似文献   
63.
本文首次报道应用酶联免疫吸附实验(ELISA),测定流行性出血热(EHF)患者尿中抗原,进行早期诊断,取得满意结果,本法系应用免疫的特异性和酶的高效能催化的敏感性相结合的一种方法,因而特异性强、灵敏度高。研究结果表明,7病日内阳性率较高,为93.89%;2病日内阳性率更高,为100%,故有早期诊断价值,本文用阻断实验证实尿中具有特异性抗原。此外,以正常人和其它疾病患者作对照,结果为阴性,证明本法特异性高。本法标本系用尿液,容易收集,方法简便,结果易判断,易于推广应用。  相似文献   
64.
目的 探讨阴茎折断伤的病因和诊治。方法 对2l例阴茎折断伤的临床资料进行回顾性分析。结果 致伤原因以粗暴性交13例,手淫5例,跌伤、撞击伤各l例,拒绝说明原因l例。B超确诊12例,阴茎海绵体造影确诊l例。12h内手术13例,超过12h手术3例,保守治疗5例。12h内手术组有2例发生阴茎白膜硬结,术后性功能正常;超过12h手术组和保守治疗组各有l例和2例并发阴茎硬结、阴茎成角畸形和勃起功能障碍。结论 阴茎折断致伤原因以粗暴性交和手淫为主;B超检查是诊断阴茎折断首选方法;早期手术能减少其并发症的发生;术中采用纵行小切口容易准确找到白膜破裂位置,且创伤小,适于临床应用。  相似文献   
65.
寒冷干燥地区平时火器伤的早期处理   总被引:3,自引:3,他引:0  
目的 探讨寒冷干燥地区平时火器伤伤情特点与早期救治方法。方法 对 1991年 1月— 2 0 0 2年 12月间 40例火器伤病人的临床救治进行回顾分析。结果  2 4例枪伤中 ,2 0例一期缝合伤口 ,均一期愈合 ,另外 4例只清创未一期缝合的伤口 ,3例愈合 ,1例感染 ;4例骨折内固定均愈合良好 ,无骨髓炎发生。 16例炸伤病人局部软组织损伤及污染比枪弹伤重 ,14例一期缝合伤口中 ,10例一期愈合 ,4例感染 ,骨折内固定 2例 ,均愈合良好 ,无骨髓炎发生。结论 寒冷干燥地区火器伤早期伤道清创时限可适当延长 ,在平时火器伤的救治中 ,对软组织条件较好的创面 ,早期清创后可一期闭合伤口和骨折内固定 ,这样可减少感染和伤残 ,促进康复  相似文献   
66.
The ICD-10 and DSM-IV classifications have both given low priority to “reactivity” to acute stress as a classificatory principle for functional psychoses. In Scandinavia, reactivity is still considered an important factor in the development of such psychoses. Reactivity is a complex concept, and its various components are historically examined. The Reactivity of Psychosis Rating Form (RPRF) was developed in order to operationalize reactivity. Seven of the 10 elements of RPRF can be rated reliably. Factor analysis of the RPRF yields three factors: stressor, onset and change, that also show high interrater reliability. Our results indicate that RPRF has both construct and discriminant validity. Further studies with the RPRF may elucidate the true status of reactivity in functional psychoses.  相似文献   
67.
Olfactory stimulation evokes a column of activity within the olfactory bulb extending from the glomerular layer to the granule cell layer that can be visualized with 2-deoxyglucose autoradiography, optical imaging, Fos protein immunohistochemistry and c-fos mRNA in situ hybridization. The Fos response to odors is typified by the activity of relatively few juxtaglomerular cells, which often occur in foci, and a large number of granule cells extending through much of the bulb. In this study, we characterized the granule cell response to an odor for which young rats had acquired a preference. Fos-like immunoreactive granule cells were quantified by image analysis, and densely stained cells were counted in a region previously shown to be responsive to peppermint odor. We found that odor-trained pups have about half the number of Fos-immunopositive superficial granule cells which respond to a learned odor than do control pups. We then determined whether there was a correlation between the juxtaglomerular cell response and the response of the superficial granule cells deep to those glomerular layer cells. We found a positive correlation between the number of juxtaglomerular cells and the number of granule cells demonstrating Fos immunoreactivity in both control and trained pups, a relationship that changed with early olfactory training.  相似文献   
68.
米索前列醇(misoprostol,米索)是人工合成的前列腺素E_1的衍生物,有多方面临床用途。80年代早期米索最先开始用于治疗消化性溃疡,尤其是对非甾体类抗炎药引起的胃十二指肠溃疡有明显疗效,对急性应激性溃疡也有预防作用。米索可引起腹泻,但因此也可治疗严重便秘的患者。随后发现米索对肝、肾有保护作用,还具明显抗炎、抗过敏作用;与其它抗早孕药合用,米索可使完全流产率大大提高;对人工流产术前的病人用米索可软化并扩张宫颈,从而减轻扩宫时病人的痛苦,使手术顺利进行。对米索的毒副作用研究发现其毒性主要表现在消化系统和雄性生殖系统,但一般比较轻微,无明显其它不良反应。故米索可谓一种高效、低毒的药物,值得临床推广。但男性患者在长期大量应用该药时需注意其对生殖系统的影响,孕妇应禁用。  相似文献   
69.
The spatial and temporal pattern of expression of the protein products of immediate early genes (IEGs) c-fos, fos B, and egr-1 were mapped in medial preoptic area (MPOA) and ventral bed nucleus of stria terminalis (VBST) during maternal behavior in rats. Immunocytochemical analysis indicated significant increases in the number of cells expressing c-Fos after 2 h of pup exposure, while Fos B levels showed a delayed response, reaching maximal levels after 6 h.  相似文献   
70.
Summary. A unilateral quisqualic acid lesion was placed in the nucleus basalis magnocellularis of 3- and 24-month-old rats, and the animals were sacrificed at different times post-surgery. The morphology and the number of the cholinergic neurons of the nucleus basalis were analyzed by means of immunohistochemistry for cholineacetyltransferase, in order to evaluate the size and severity of the lesion. Immunohistochemistry for the immediate early gene c-fos was also performed in order to clarify its role in the process of neurodegeneration following the excitotoxin injection. The DNA laddering and TUNEL techniques were used to define the type of cell death involved. At short times (4 hr) the lesion induced alterations in the morphology of cholinergic neurons of the nucleus basalis. Subsequently, a significant decrease in the number of neurons was found in comparison to the contralateral unlesioned side. In the older animals the loss of cholineacetyltransferase immunoreactivity had an earlier onset (4 hr) than in the young (24 hr). C-fos expression was induced by the lesion and not by saline injection in the nucleus basalis and in neighbouring areas of the brain as early as 4 hr after surgery. The c-fos protein was no longer present by 24 hr. Furthermore, the c-fos gene product was consistently absent from the nuclei of cholinergic cells. The aged animals exhibited a slower and smaller increase in c-fos as measured by counting the labelled nuclei in the injected area. Analysis of DNA fragmentation did not provide any evidence for apoptosis as the type of cell death involved in the cholinergic degeneration. These results indicate that the c-fos protein might have a protective role in the response to excitotoxic lesions. Furthermore, we have shown that the aged brain displays a reduced ability to produce a c-fos-mediated plastic response to the lesion. Received December 17, 1997; accepted February 17, 1998  相似文献   
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