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131.
We studied the effects of Wallerian degeneration in the cerebral peduncle shown by magnetic resonance imaging (MRI) following a supratentorial vascular lesion, to identify the somatotopic localisation of the descending cortical tracts. Patients with a lesion involving a large area of a cerebral hemisphere had an area of abnormal signal intensity in the whole cerebral peduncle, suggesting Wallerian degeneration of all the whole descending cortical tracts. With a small lesion confined to the precentral gyrus, corona radiata, or posterior limb of the internal capsule there was an abnormal signal at the centre of the peduncle, suggesting degeneration of the precentrospinal tract. Those with a small lesion confined to the paracentral gyrus had an abnormal area slightly lateral to the centre of the peduncle, suggesting degeneration of the parietospinal tract. Patients with a lesion of the parietal or temporal lobes, not including the paracentral or precentral gyri, corona radiata, or the posterior limb of the internal capsule, had an abnormal area laterally in the peduncle, suggesting degeneration of the parietopontine or temporopontine tract.  相似文献   
132.
目的:在女性性早熟患儿中检测雌激素受体基因6号外显子及内含子基因序列可能存在的突变。方法:PCR扩增雌激素受体基因6号外显子及内含子,对扩增产物进行DNA序列分析。结果:在6号内含子一侧,发现两个100%连锁的单核苷酸多态性(SNPs),分别为.53G—67A和53T—67G。结论:这一对单核苷酸多态性并不引起氨基酸的替代,与女孩性早熟的发生也无关,但是否和其他疾病有连锁关系尚待进一步探讨。  相似文献   
133.
视网膜脱离手术复位后ERG的恢复   总被引:5,自引:0,他引:5  
赵朝霞 《眼科研究》1996,14(2):124-127
为探讨视网膜脱离手术复位后ERG的改变,对35例(35眼)患者进行手术前后ERG检测,结果表明;(1)视网膜脱离术前ERGa、b波幅明显低于有视网膜格子样变性而无脱离者。(2)手术复位后ERGa、b波幅随时间延长逐渐回升。(3)视网膜脱离范围二个象限以内者ERGa、b波幅回升高于二象限以上者。(4)手术范围一个象限以内者与超过一个象限者相比前者ERG恢复优于后者。(5)视网膜脱离时间2月以内与超过2月相比,ERG恢复前者明显优于后者。结果证实视网膜脱离术后ERG恢复与手术后时间、脱离范围、病程及手术范围密切相关。  相似文献   
134.
本文采用RP-HPLC方法对紫苏油及其习用品白苏油、野苏油甘油酯进行了定性定量分析。利用HPLC分析油脂也为中药材真伪鉴别提供了一条有效途径。  相似文献   
135.
A considerable proportion of headache patients fulfill the criteria of "drug abuse" (definition according to the International Headache Society [IHS] criteria). These patients exhibit markedly reduced vigilance and continuous performance, as shown by the results of critical flicker frequency (CFF) analysis.
The present study deals with the question whether this impairment of vigilance and continuous performance is reversible. Forty-eight headache patients with drug abuse were investigated three times by means of CFF analysis: immediately before (A), immediately after (B), and 3 weeks after having finished (C) inpatient drug withdrawal.
Immediately after withdrawal, a significant decrease of headache intensity was observed. The CFF values, however, remained unchanged at a depressed level, probably due to withdrawal medication and the initial sedative side effects of thymoleptic agents (given as prophylaxis).
Three weeks after withdrawal, however, the CFF values were significantly improved, and were now within a range not far from the normal values known from a healthy general population. Thus, even after many years of drug abuse, headache patients have a good chance to improve their vigilance and continuous performance and to reach normal or close to normal levels.  相似文献   
136.
标记抗原在贮存过程中,由于受幅射分解和脱碘影响而使免疫活性和生物活性降低。我们对自制的~(125)碘-绒毛膜促性腺激素进行了实验观察。结果显示:贮存1月后,其免疫活性和生物活性分别降低了33.1%和44.0%;经电泳纯化后的标记物的免疫活性和生物活性明显提高,分别达到了最初的90.5%和95.3%。  相似文献   
137.
Gingival crevicular fluid (GCF) IL-8 and IL-1,1β levels were determined by sandwich enzyme-linked immunosorbent assays. Associations between IL-8 and IL-1β GCF levels, and between these cytokines and patient estrogen status were evaluated. IL-8 and IL-1β were detected more frequently and in higher amounts/30 s GCF sample in estrogen-deficient patients than in estrogensufficient patients. IL-8 and IL-1β GCF levels were significantly correlated. These lindings suggest that GCF IL-8 levels are associated with patient estrogen status and local IL-1β concentrations.  相似文献   
138.
目的 制备甘草蛋白免疫磁性微球,并建立快速、精确的免疫磁性捕获ELISA法检测甘草蛋白。方法 采用种子聚合法合成聚苯乙烯磁性微球,并以兔抗甘草蛋白IgG抗体致敏,制备特异性捕获甘草特征蛋白的免疫磁性微球。以生物素标记抗体为示踪抗体,结合辣根过氧化物酶标亲和素建立ELISA检测系统,用于甘草药材和含甘草中成药中甘草蛋白的分析。结果 利用该方法对甘草药材和中成药中甘草蛋白抗原检测,检测灵敏度达到10ng/mL。结论 免疫磁性捕获ELISA检测技术方便、快速、准确,为生药的品种鉴定及中成药的质量控制提供一种新方法。  相似文献   
139.
A 78-year-old man treated with amiodarone for recurrent ventricular tachycardia, had sequential placement of a bipolar VVI pacemaker and an automatic implantable cardioverter defibrillator (AICD). During defibrillation threshold testing, there was failure to capture of the pacer in the post-shock period. The time of failure to capture appeared energy-related: the greater the energy delivered, the longer the failure to capture. Careful attention will be necessary in constructing combined AICD/pacemaker units.  相似文献   
140.
Abstract Pericardial tamponade remains a diagnostic challenge to the clinician especially when the patient is well compensated hemodynamically. We report an unusual case who sought medical help 1 month after having been stabbed in his chest. An investigation revealed a perforation of the myocardium and a pericardial tamponade. The patient survived thanks to a large organized clot that plugged the perforation. The patient was exposed to increased risk due to delayed onset, recognition, and therapy of the tamponade. Most reports on this subject deal with acute pericardial tamponade. Only few cases of delayed pericardial tamponade have been reported. A review of the relevant literature and the therapeutic approaches are discussed.  相似文献   
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