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991.
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Most rhinovirus serotypes use intercellular adhesion molecule-1 (ICAM-1) as the receptor to enter cells, but ICAM-1 expression has not been detected on normal nasal epithelial cells. During experimental rhinovirus infection, expression of ICAM-1 on nasal epithelial cells was examined with immunohistochemical staining of nasal scrape biopsy specimens, and levels of soluble ICAM-1 in nasal lavage fluid were measured by sandwich enzyme-linked immunosorbent assay technique. Expression of ICAM-1 on nasal epithelial cells increased following inoculation in 20 of 23 infected subjects. The median number of ICAM-1-positive cells per 6.25-mm(2) area of stained biopsy specimen was 0 in control samples (day 20 or 33 after inoculation), and in those without infection, 6 on day 1 (P< or =.05), 14.5 on day 3 (P< or =.01), 1.5 on day 5, and 0 on day 9. In a different group of volunteers, soluble ICAM-1 in nasal lavage fluid was higher on days 1 and 3 compared with preinoculation levels (P< or =.001), but only 11 of 23 infected subjects had a 2-fold or greater increase. Up-regulation of ICAM-1 receptor expression on nasal epithelial cells occurred within 24 hours after inoculation in experimental rhinovirus infections (prior to onset of symptoms) and declined promptly by day 5.  相似文献   
995.
This study was undertaken to determine whether angiotensin receptor blockers are as renoprotective as angiotensin-converting enzyme inhibitors in an experimental model of chronic interstitial renal disease. Groups of rats received one of the following treatments for 1 week: (1) enalapril, (2) diltiazem, (3) a cocktail of hydralazine, reserpine, and hydrochlorothiazide, or (4) irbesartan (an AT1 antagonist). The animals were injected with bromoethylamine (200 mg/kg), and antihypertensive treatment continued for 1 month. All drugs were effective in lowering the mean arterial pressure. The bromoethylamine-treated rats developed albuminuria and sustained a 40-50% decrease in creatinine clearance. Enalapril and irbesartan reduced albuminuria, but only enalapril partially prevented the decline in creatinine clearance and lowered the number of ED-1-positive cells. Diltiazem and cocktail had no effect on proteinuria, creatinine clearance, or ED-1 cells. In this experimental model, the effects of enalapril and irbesartan were not identical. Both drugs reduced proteinuria, but enalapril was more effective in protecting the renal function. The fact that the AT1 antagonist protected against albuminuria but did not affect the clearance of creatinine implies that the results seen with angiotensin-converting enzyme inhibition may be in part due to an effect on angiotensin II via AT2 receptor blockade or through an effect on bradykinin.  相似文献   
996.
OBJECTIVE: To describe the relationship between Professor Charcot and Brazil. BACKGROUND: During the XIX century, French Neurology and its most prominent figure, Professor Charcot, dominated the area of nervous system diseases in the world. METHOD: We have reviewed some of the main publications about Charcot's life, the biography of Dom Pedro II, Emperor of Brazil and the development of Neurology in Brazil. RESULTS: Among the most important patients in Charcot's practice was the Emperor of Brazil. Dom Pedro II became a close friend of Charcot and he was a distinguished guest at Charcot's house, particularly at Tuesday soirées on boulevard St. Germain. In 1887, during the visit of Dom Pedro II to France, Charcot evaluated him and made the diagnosis of surmenage. In 1889, Dom Pedro II was disposed and went to Paris, where he lived until his death in 1891. Charcot signed the death certificate and gave the diagnosis of pneumonitis. Charcot had a passionate affection for animals, a feeling shared by Dom Pedro II. Dom Pedro II was affiliated to the French Society for the Protection of Animals. It is conceivable that Charcot's little monkey, from South America, was given to him by Dom Pedro II. The Brazilian Neurological School was founded by Professor A. Austregésilo in 1911, in Rio de Janeiro. At the time, of Charcot's death in 1893, his influence was still very important in the whole world. He and his pupils played a major role in the development of Brazilian Neurology. CONCLUSION: Professor Charcot had a close relationship with the Emperor of Brazil, Dom Pedro II. He was his private physician and they were close friends. The neurological school, created by professor Charcot, contributed significantly, albeit in an indirect way, to the development of Brazilian Neurology, starting in 1911, in Rio de Janeiro, by Professor A. Austregésilo.  相似文献   
997.
We describe a 41 years old woman who 17 years ago presented hypotonia and proximal muscular weakness in the upper and lower limbs. On neurological examination, the biceps, triceps and Achilles reflexes were absent; the brachioradialis reflexes were decreased and the patellar reflexes were normal. There was bilateral Babinski sign. The remainder of the neurological examination was unremarkable. In the investigation a myopathic pattern was found in the electromyography. The nerve-conduction study was normal; a ELISA method for HTLV-I antibodies was positive in the blood and in the cerebral spinal fluid. The muscle biopsy showed inflammatory myopathy, compatible with polymyositis. This paper focuses the polymyositis in the beginning of an HTLV-I infection case.  相似文献   
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999.
BACKGROUND: Relaxin, a hormone of the insulin-growth factor family, promotes collagen remodeling. In rodent models of pulmonary and dermal fibrosis, relaxin reduced interstitial fibrosis. To study relaxin's effect in renal disease, we used the experimental bromoethylamine (BEA) model that leads to severe renal interstitial fibrosis, a decrease in glomerular filtration rate, and albuminuria at one month. METHODS: Rats were injected with BEA one week prior to implantation of an osmotic pump delivering relaxin (2 microg/hour) or vehicle continuously for 28 days. RESULTS: BEA caused a significant decrease in creatinine clearance, which was partially prevented by relaxin. In the relaxin-treated BEA rats, serum creatinine was normal, and albumin excretion was slightly decreased. By morphometric measurement, relaxin administration was associated with a significant decrease in interstitial fibrosis at the corticomedullary junction. This was accompanied by a decrease in the number of ED-1 positive cells (an index of macrophage infiltration) and in the intensity of immunohistochemical staining for transforming growth factor-beta. This antifibrotic effect of relaxin did not appear to be mediated by systemic hemodynamic changes since the mean arterial pressure was not significantly different among the groups. CONCLUSIONS: Relaxin may have a useful application in decreasing interstitial fibrosis and thereby slowing the progression of renal disease.  相似文献   
1000.
背景:现有的转移性肾细胞癌(RCC)的治疗方法非常有限,所以急需寻找新的有效的治疗方法。Sunitinibmalate为口服多靶点酪氨酸激酶抑制剂,并且在一项对细胞因子难治性转移性RCC患者的初期研究中已经显示有效果。目的:证实sunitinib作为患有转移性透明细胞(clear-cell,该恶性肿瘤中的主要细胞类型)RCC患者二线治疗药物的抗肿瘤功效。方法:此研究为一项公开标签、单一试验组、多中心的临床试验。在2004年2月~10月之间招募患者,并随访至疾病进展、发生严重的毒性作用或者受试者要求退出试验为止。试验收录了106例先前经过细胞活素疗法治疗后…  相似文献   
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