首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   333篇
  免费   13篇
  国内免费   2篇
儿科学   5篇
妇产科学   1篇
基础医学   9篇
临床医学   23篇
内科学   42篇
皮肤病学   145篇
神经病学   25篇
特种医学   4篇
外科学   42篇
综合类   3篇
预防医学   7篇
药学   34篇
肿瘤学   8篇
  2023年   1篇
  2022年   2篇
  2021年   4篇
  2020年   1篇
  2019年   5篇
  2018年   6篇
  2017年   2篇
  2016年   6篇
  2015年   6篇
  2014年   11篇
  2013年   4篇
  2012年   11篇
  2011年   20篇
  2010年   6篇
  2009年   11篇
  2008年   11篇
  2007年   15篇
  2006年   14篇
  2005年   23篇
  2004年   20篇
  2003年   15篇
  2002年   26篇
  2001年   32篇
  2000年   24篇
  1999年   11篇
  1998年   2篇
  1997年   1篇
  1996年   2篇
  1994年   3篇
  1993年   1篇
  1992年   6篇
  1991年   6篇
  1990年   8篇
  1989年   5篇
  1988年   1篇
  1987年   4篇
  1986年   6篇
  1985年   2篇
  1984年   1篇
  1983年   2篇
  1982年   1篇
  1979年   2篇
  1978年   4篇
  1976年   1篇
  1975年   1篇
  1964年   1篇
  1955年   1篇
排序方式: 共有348条查询结果,搜索用时 15 毫秒
1.
A 54 year-old woman developed approximately 150 generalized glomus tumors since she had been 23 years old. Painful tumors showed more glomus cells than those being not painful. Furthermore, the patient suffered from persisting congenital capillary hemangioma (strawberry mark). Histological examination revealed that glomus cells were located in the vessel walls. The large amount of Dopa found in the glomus tumor tissue supports the assumption that it may be innervated by adrenergic efferent nerves.  相似文献   
2.
We report on a 21-year-old man professionally exposed to mercury, who developed lichen planus. This case must be regarded as a dispositional reaction and is in Germany entitled to indemnification in terms of a "quasi-occupational disease". The clinical signs and the probably non-allergic pathomechanism are comparable with those of lichen planus induced by gold. In diseases due to occupational intoxication, we face an individual disposition regarding the degree of clinical symptoms, which has to underly any expert opinion on indemnity.  相似文献   
3.
Purpose. Develop and evaluate systems to prevent aminopeptidase N caused enzymatic degradation of perorally administrated peptide drugs. Methods. Bacitracin was covalently bound to the unabsorbable carrier matrix poly(acrylic acid) (paa) in order to avoid any dilution effects of the inhibitor in the intestine as well as systemic toxic side effects. The inhibitory effect of this conjugate, of neutralized paa and N-acetylcysteine was evaluated using a brush border membrane model. Results. Whereas within 6 h of incubation 65.3 ± 3.7 mol/1 of the substrate (L-leucine p-nitroanilide) was hydrolyzed under our assay conditions, this metabolism was reduced to 44.5 ± 6.3 mol/1 and 49.0 ± 8.8 mol/1 (n = 3–5; ± S.D.) using 1.5% bacitracin-polymer conjugate and 0.5% N-acetylcysteine, respectively. The same amount of bacitracin as immobilized to the polymer exhibited a comparably weaker inhibitory effect. Neutralized paa did not inhibit membrane bound aminopeptidase N. Covering the membrane with a thin mucus layer led to a significantly lowered inhibitory effect of all tested agents. Conclusions. The immobilization of enzyme inhibitors to a carrier matrix and the use of N-acetylcysteine as a novel inhibitor are promising strategies in order to overcome the enzymatic barrier caused by membrane bound peptidases. However the use of effective mucolytic agents seems to be a prerequisite.  相似文献   
4.
5.
6.
A wide diversity of organisms exists in soil. Well-adapted groups can be found in extreme environments. A great economic and metabolic potential for extremozymes produced by organisms living at extreme environments has been reported. Extreme characteristics such as high salt content and high pH level make the soil of the former Texcoco Lake a unique place which has not been exploited. Therefore, in this study, 66 strains from soil of the former Texcoco Lake were isolated and phylogenetically analyzed using universal oligonucleotide primers. Different genera such as Kocuria, Micrococcus, Nesterenkonia, Halomonas, Salinicoccus, Kurthia, Gracilibacillus, and Bacillus were found. However, only 22 from all isolated strains were identified at specie level.  相似文献   
7.
OBJECTIVES: We sought to validate a new noninvasive technique to determine central venous pressure (CVP) using high-resolution compression sonography. BACKGROUND: Information concerning CVP is crucial in clinical situations, including cardiac failure, volume overload, and sepsis. The measurement of CVP, however, requires puncture of a vein with attendant risk of complication. METHODS: After a proof-of-concept study in healthy subjects, a prospective blinded evaluation was performed comparing CVP measurement using a central venous catheter with measurement using compression sonography in critically ill (intensive care unit) patients. RESULTS: In healthy subjects with experimentally induced venous hypertension with a wide range of pressure values, a strong correlation (r = 0.95; p < 0.001) between noninvasive and invasive peripheral venous pressure at the forearm was shown. High interobserver agreement with an intraclass correlation coefficient of 0.988 shows excellent reliability of the system. Noninvasive peripheral venous pressure measurement at the forearm showed a good correlation with CVP in 50 intensive care unit patients with the forearm positioned both below heart level (r = 0.84; p < 0.001) and at heart level (r = 0.85; p < 0.001). The mean difference between invasive and noninvasive measurement was negligible (-0.1 +/- 3.5 cm H2O and -0.7 +/- 3.4 cm H2O, respectively). CONCLUSIONS: Controlled-compression sonography is a valuable tool for measuring venous pressure in peripheral veins and allows reliable indirect assessment of CVP without intravenous catheterization.  相似文献   
8.
Journal of Neurology - Oral Factor Xa inhibitors for the prevention of stroke in atrial fibrillation require dose adjustment based on certain clinical criteria, but the off-label use of the reduced...  相似文献   
9.
10.
In the present study, the acute vasoactive effect of a dried hydrophilic extract of garlic with 600 mg active substance (Alliosan) was investigated in 10 healthy volunteers. Laser-Doppler fluxmetry, video capillary microscopy and transcutaneous partial pressure of oxygen measurements were used for the objective assessment of functional and morphological parameters. An increase in perfusion could be demonstrated by these means. This was based on an increase in erythrocyte flow velocity of up to 2 h duration, which was mainly due to vasodilation in both arterial and venous vessels. A change in transcutaneous partial pressure of oxygen or an influence on sympathetically-mediated vasomotor reflexes could not be demonstrated. Furthermore, there was no evidence of an influence on reactive hyperaemia after controlled hyperthermia. The test substance was shown to increase the cutaneous microperfusion.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号