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41.
Mini rats (Jcl: WistarTGN(ARGHGEN) 1Nts) (MRs) are Wistar rat (WR)-derived transgenic rats in which the expression of growth hormone (GH) gene is suppressed under the presence of antisense RNA transgene. In order to evaluate the effects of GH-deficiency on the acute injury by external stimuli, the dorsal skin responses to a single topical application with 20% hydrogen peroxide (HPO), one of the environmental oxidative stressors, were histologically compared between male MRs and WRs of 8 weeks old, whose hair cycle was under the telogen phase. As a result, formation of granulation tissues, reepithelialization and regrowth of hair follicles were delayed in MRs compared with WRs. While hair follicles of MRs of this age are under a long-lasting telogen phase after their 2nd cycle, a new hair cycle started not only in the HPO-applied area but also in the solvent-applied area with a little time lag. These findings suggest that GH-deficiency may influence the skin responses to the external chemical stimuli.  相似文献   
42.
To assess the significance and accuracy of noninvasive tests in detecting significant coronary artery disease (CAD; greater than 50% stenosis), the Master's exercise test, treadmill exercise test and dipyridamole-loading myocardial perfusion scintigraphy were performed and their results were compared with coronary angiographic findings in 60 patients with angina but without myocardial infarction. Among these, 27 patients had significant CAD. The Master's test performed in outpatient clinics had an 85% sensitivity and a 76% specificity in detecting significant CAD, when the degree of ST depression was equal to or exceeded 1 mm. The sensitivity further improved to 96% by adding chest pain to the criteria; then all patients with multivessel disease or critical ischemia were identified by the Master's test. Treadmill tests performed after admission had a 78% sensitivity and a 67% specificity. When the severity of ischemia was judged either by exercise capacity or the degree of ST depression or the coronary T wave, the treadmill test was superior to the Master's test. Although patients without significant CAD had longer exercise capacity and the higher maximum heart rate in the treadmill test than did those in the Master's test, these trends were similar but less marked in patients with significant CAD. Dipyridamole-loading myocardial perfusion scintigraphy showed an excellent sensitivity and specificity; 96% and 94%, respectively, in detecting significant CAD. It was particularly useful in distinguishing false positive exercise results due to left ventricular hypertrophy and coronary spasm and that in women, from true positive results. In conclusion, the Master's test is a simple and useful method for screening CAD in community hospitals and in outpatient clinics.  相似文献   
43.
We report here an unusual case of fibrous histiocytoma in which an area of xanthogranuloma was observed histologically. Our case suggests that adult xanthogranuloma is a variant of fibrous histiocytoma.  相似文献   
44.
The utility of MRI using magnetization transfer (MT) enhanced pulse sequences to diagnose hepatic cirrhosis in a rat model was investigated. Hepatic T1 was measured with and without MT off-resonance RF pulses in 17 treated and six control rats. The livers were evaluated histologically, and the hydroxyproline content quantitatively measured. We did not find a statistically significant linear correlation between the MR relaxation times and the degree of tissue injury. However, the MR measurements performed with MT were superior to those without differentiating the treated and control groups. Specifically, the T1 times were 695 ±76 ms for the treated group, versus 748 ± 61 ms in the controls; P= 0.095. The T1sat times were also lower in the treated group, with statistical significance: 367 ± 51 ms versus 421 ± 38 ms, P = 0.016. Finally, the change in the relaxation rates (the inverse of the relaxation times) with and without saturation were 1.31 ± 0.22 s?1 (treated group) versus 1.05 ± 0.12 s?1 (controls), which differed significantly, P= 0.001.  相似文献   
45.
BALB/c mice infected with 10(5) pfu of the D variant of encephalomyocarditis virus were examined histopathologically during the subacute stage of infection. Main pathologic changes were observed in the brain, heart (massive myocardial necrosis with subsequent organization (i.e., replacement of necrotic myocardium by connective tissue) and congestion and dilatation of the right ventricle) and pancreas (moderate degranulation of beta-cells resulting in elevation of blood glucose level). The brain lesions were found most frequently in the pyramidal layer of the hippocampus and the granular layer of the cerebellum and were characterized by degeneration of neurons containing virus antigens. Perivascular mononuclear cell infiltration, spreading to the adjacent brain tissue, and thrombosis in small vessels were also frequently seen. Focal loss of neurons and gliosis developed later in these lesions.  相似文献   
46.
We evaluated regional blood flow and oxygen metabolism in the cerebral and cerebellar cortices of 15 patients with unilateral major cerebral artery occlusive disorders with PET. These patients showed a cortical blood flow asymmetry in middle cerebral artery distribution. Only subcortical abnormalities were detected on computed tomography. Nine patients showed crossed cerebellar hypoperfusion, a reduction in contralateral cerebellar blood flow, while six did not. No difference in the degree of cerebral blood flow asymmetry existed between the two patient groups. However, oxygen metabolism asymmetry was more pronounced and was more closely matched to blood flow asymmetry in patients with crossed cerebellar hypoperfusion. These findings suggest that a major cause of cerebral cortical blood flow reduction is reduced metabolic demand in patients with crossed cerebellar hypoperfusion. Crossed cerebellar hypoperfusion may have clinical significance as a reflection of the cerebral metabolic state on blood flow images.  相似文献   
47.
Invasive mycosis in solid organ transplantation is mainly caused by Candida and Aspergillus, and its risk is higher in small bowel, liver, pancreas, and lung transplantation. Although limited analyses propose not a few risk factors for invasive mycosis in respective transplanted organs, the efficacy of prophylactic use of antifungal agents or preemptive treatments based on the information is not fully supported by prospective randomized controlled clinical data. The final guideline should be helpful for tailor-made evidence-based management based on the stratification of patients by pretransplant, surgical, immunosuppressive and organ specific characteristics. The process of repeated proposals and verification in a large number of patients is necessary.  相似文献   
48.
目的:研究NPHS1两种新突变编码蛋白在细胞内的分布与先天性肾病综合征发病机制的关系。方法:构建野生型和两种突变型NPHS1克隆,并转染至COS7细胞内,应用免疫荧光双标记的方法,分别进行细胞内及细胞表面的荧光标记,通过共聚焦显微镜对裂隙膜分子Nephrin在细胞内的分布进行研究。结果:野生型Nephrin表现为细胞内和细胞膜染色模式;V822M和C265R则主要为细胞内内质网染色模式,细胞膜着色几乎缺失。结论:突变的Nephrin蛋白由于错误折叠,不能由内质网被输送至细胞表面,这可能是先天性肾病综合征发病的机制之一。  相似文献   
49.
An automated on-line method for simultaneous analysis of five phenothiazine drugs by high-performance liquid chromatography (HPLC)/sonic spray ionization mass spectrometry (SSI-MS) has been established, using backflush column switching. A 400-μl portion of serum sample diluted 81-fold with distilled water was subjected to the on-line system. In the system, an Oasis HLB cartridge was used as the precolumn for extraction; large molecules such as proteins in serum were discarded by use of distilled water containing 0.1% formic acid as a mobile phase. After switching a valve, the analytes trapped in the precolumn were eluted in the backflush mode and separated by a Chromolith Performance RP-18e column, which is composed of C18-bonded monolithic silica. The column effluents were then introduced into the SSI-MS. The present method provided successful separation and determination of six phenothiazines including an internal standard. Satisfactory linearities, reproducibility, and sensitivity were obtained at concentration levels that matched the toxic levels of phenothiazines. All drug peaks appeared within 18 min, and the system could be reequilibrated in only about 8 min for the next run. Because of the simplicity and rapidness of the method, it is likely to be useful in the fields of emergency medicine and forensic toxicology.  相似文献   
50.
PURPOSE: We assessed the feasibility of utilizing three-dimensional (3D) phase sensitive inversion recovery (IR) images for preoperatively determining deep brain stimulator position. METHODS: We measured geometric distortion with a grid phantom and evaluated images of 3 volunteers to determine optimum imaging parameters for 3D phase sensitive IR. RESULTS: Geometric distortion measured less than 1.0%. Respective inversion and recovery times, which provided high T(1) contrast between the subthalamic nucleus and adjacent tissue, were 200 and 4000 ms. In studies of 3 volunteers and 2 patients, the subthalamic nucleus was clearly depicted in 3D phase sensitive IR images. The measured coordinates of the subthalamic nucleus agreed well with those calculated by conventional estimation from midpoint of the anterior and posterior commissure. CONCLUSION: Three-dimensional phase sensitive inversion recovery was useful in visualizing the subthalamic nucleus for effective deep brain stimulation.  相似文献   
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