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本文阐述了我院自行研制的气垫床工作模式转换器的结构、工作原理及应用效果。  相似文献   
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Intraocular pressures and optic disc hemorrhages were studied in all cases of manifest glaucoma detected in a defined population over a decade. High intraocular pressure was found to be an unreliable signat the detection of a glaucomatous visual field defect and an unusual finding 5–10 yearsbefore. The prevalence of optic disc hemorrhages at the detection of a glaucomatous visual field defect was 33%. All but 9 of 44 persons with manifest glaucoma were found to have had at least one optic disc hemorrhage at one time or another.  相似文献   
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2006年10月31日,对于郑州和医疗器械行业是一个好日子,因为第56届中国国际医疗器械秋季博览会暨第3届中国国际医疗器械设计与制造技术展览会在期待和掌声中于郑州国际会展中心隆重开幕。这个以其造型新颖别致,富有强烈的时代感和现代感而成为郑州的标志性建筑的展览馆在金秋时节又一次盛装迎来了国内外客人。国家食品药品监督管理局医疗器械司副司长常永亨、总后卫生部药品器材局副局长石虹、国家发改委价格司医药价格处处长郭剑英等来自行业主管单位的领导,河南省省长史济春、郑州市市长赵建才、原河南省人大副主任钟力生、河南省药监局副…  相似文献   
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The beta-adrenoceptor (beta-AR)-stimulatory guanine nucleotide-binding (Gs) protein system has been shown to play important roles in the cardiovascular system. The gene encoding the alpha-subunit of Gs proteins (GNAS1) is a candidate genetic determinant for hypertension. Because alcohol consumption is known to affect blood pressure partly through the beta-AR-Gs protein system, we examined the possible interaction between GNAS1 T393C polymorphism and drinking status in the association with hypertension in the present study. As a result, a non-significant but reasonable trend supporting the presence of an interaction was shown (p = 0.076). In line with this trend, the T393C polymorphism significantly interacted with drinking status in the association with systolic blood pressure (p = 0.028). Moreover, supporting the presence of an interaction, T allele carriers consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than CC homozygotes in non-drinkers and light drinkers. In contrast, CC homozygotes consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than T allele carriers in moderate to heavy drinkers. The present study also showed a significant interaction between the T393C polymorphism and drinking status in the association with pulse pressure (p = 0.026), reflected by a significant association between the T393C polymorphism and pulse pressure in moderate to heavy drinkers (p = 0.026). These findings may be helpful in conducting further molecular and biological studies on the relationship among the effects of alcohol, the beta-AR-Gs protein system, and hypertension.  相似文献   
16.
The authors undertook comparative study of the Na, K-ATPase activity in the red cells, ghost corpuscles, and in the cortex and medulla of kidneys of rats with experimental glomerulonephritis (GN) induced by injection of nephrotoxic serum (NTS), during an acute course of the process (1 and 2 weeks after NTS injection) and in chronic affection of the kidneys (10 weeks after NTS injection). The activity of the enzyme both in the red cells and in the ghost corpuscles was reduced significantly, by 28 and 22%, respectively, in the acute period of the disease (one week after NTS injection) but was restored to normal values in the period of chronic affection of the kidneys. The activity of the enzyme did not change in the cortex during the whole period of the study, but in the medulla it diminished in the acute period of the disease and remained reduced (by 27% on the average) during the chronic phase. It is concluded that reduction of the enzyme activity in the studied objects was not caused by the presence of endogenous inhibitors of the enzyme. It is suggested that reduction of Na, K-ATPase activity in the renal medulla may be one of the factors of increase of Na and water excretion in the urine in the chronic phase of GN.  相似文献   
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A retrospective study was performed on 20 patients with adenoid cystic carcinomas of major salivary glands to see if DNA. patterns correlated with their prognoses. Fourteen tumors were found to be DNA. diploid; 6 were DNA aneuploid. Histologically, all DNA-aneu-ploid tumors had solid components, compared with only 5 of the DNA-diploid tumors. All of the DNA-aneuploid tumors recurred, in contrast to only 2 of the DNA-diploid tumors; the difference was highly significant (P<0.001). All of the patients with no recurrences had DNA-diploid tumors. In our study, DNA measurements of adenoid cystic carcinomas gave statistically significant information about prognosis and correlated to histological grading. We propose that evaluation of DNA content may be performed before planning the treatment of adenoid cystic carcinomas.  相似文献   
19.
对16例垂体腺瘤采用单侧鼻前庭切口经蝶切除,效果满意,既可减少手术创伤,又缩短了手术距离,且避免了美容缺陷,是一种设计巧妙,较为实用的手术方法,尤其适用于生长激素腺瘤。  相似文献   
20.
In a group of 43 smelter workers exposed to inorganic arsenic dust for 13-45 years, nerve conduction velocities (NCVs) were significantly lower in two peripheral nerves as compared with matching referents. With multivariate data analysis, a significant negative correlation was found between cumulative absorption of arsenic and NCV in four examined nerves and the sural amplitude. Clinical symptoms of neuropathy and other symptoms related to arsenic exposure were moderate, though the difference between the groups was significant. The mean total absorption of arsenic was calculated to be less than 5 g, and the maximal absorption about 20 g. These data indicate that the adverse effect of arsenic on the peripheral nerves is dependent on long-term exposure rather than on short-term fluctuations in exposure levels. © 1994 Wiley-Liss, Inc.  相似文献   
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