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   303篇
  免费   14篇
  国内免费   5篇
耳鼻咽喉   1篇
儿科学   18篇
妇产科学   3篇
基础医学   41篇
口腔科学   3篇
临床医学   31篇
内科学   67篇
皮肤病学   7篇
神经病学   15篇
特种医学   49篇
外科学   25篇
综合类   5篇
预防医学   23篇
眼科学   2篇
药学   19篇
中国医学   1篇
肿瘤学   12篇
  2021年   6篇
  2020年   2篇
  2019年   4篇
  2018年   5篇
  2017年   2篇
  2015年   4篇
  2014年   10篇
  2013年   7篇
  2012年   11篇
  2011年   18篇
  2010年   12篇
  2009年   4篇
  2008年   8篇
  2007年   13篇
  2006年   14篇
  2005年   15篇
  2004年   11篇
  2003年   6篇
  2002年   3篇
  2001年   4篇
  2000年   3篇
  1999年   5篇
  1998年   15篇
  1997年   12篇
  1996年   15篇
  1995年   8篇
  1994年   9篇
  1993年   7篇
  1992年   5篇
  1991年   3篇
  1990年   4篇
  1989年   3篇
  1988年   8篇
  1987年   4篇
  1986年   5篇
  1985年   4篇
  1983年   3篇
  1982年   4篇
  1981年   4篇
  1980年   4篇
  1979年   4篇
  1978年   6篇
  1977年   10篇
  1976年   3篇
  1975年   2篇
  1968年   2篇
  1930年   1篇
  1928年   2篇
  1925年   1篇
  1924年   1篇
排序方式: 共有322条查询结果,搜索用时 15 毫秒
1.
Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
2.
Pharmaceutical Research -  相似文献   
3.
4.
Medial border of the perirenal space: CT and anatomic correlation   总被引:11,自引:0,他引:11  
  相似文献   
5.
6.
Circannual variation in lymphocyte subsets, revisited   总被引:2,自引:0,他引:2  
BACKGROUND: Circadian and circannual variations in lymphocyte subsets, especially CD8+ T-lymphocytes, have been reported. This study focuses on CD4+ T-lymphocyte seasonal variation over a 6-year 8-month period. STUDY DESIGN AND METHODS: Lymphocyte subsets were quantitated monthly for four healthy individuals from 1986 through 1992 as part of a flow cytometry quality-control program. RESULTS: In general, there were no significant seasonal changes in the total number of white cells or in total lymphocyte counts. The absolute numbers of CD4+ T-lymphocytes were lowest in summer when the CD8+ T-lymphocytes were highest. Mean CD4+ T-lymphocyte counts were 846, 967, 618, and 695 per microL for Subjects 1 through 4, respectively, in winter and 432, 670, 355, and 766 per microL, respectively, in summer. Two healthy subjects had CD4+ T-lymphocyte counts lower than 300 per microL on one or more occasions during the study period. In three of the four subjects, the percentage of B-lymphocytes in winter was almost double that in summer. In one of the four subjects, no circannual rhythm was observed in these lymphocyte subpopulations. CONCLUSION: The seasonal variation in CD4+ T- lymphocyte counts demonstrated in three healthy individuals over almost 7 years is again of interest in light of renewed consideration of using surrogate tests, such as CD4+ T-lymphocyte counts, to screen for AIDS- like diseases that may be in the blood supply.  相似文献   
7.
A rapid microagglutination test has been developed which can be performed in 30 minutes. Ninety-seven percent of 96 patients diagnosed as having Legionella pneumophila (serogroup 1) infection by indirect immunofluorescence were also detected by the rapid microagglutination test.  相似文献   
8.
Glutathione (GSH), GSH peroxidase (GPX), GSH reductase (GRD), superoxide dismutase (SOD) and catalase-like enzyme activity were quantified in seminal plasma from normozoospermic patients, men with known distal ductal occlusion, proven fathers and male partners of couples receiving in-vitro fertilization (IVF) treatment for both male and female causes. Glutathione was non-detectable (< 2.5 microM) in seminal plasma. None of the enzyme activities per unit volume were lower in semen from vasectomized men, suggesting that they did not originate substantially from the testis or epididymis. The strongest relationships between enzyme activities and accessory gland markers were between zinc and GRD (r = 0.678), SOD (r = 0.602) and GPX (r = 0.548), suggesting a largely prostatic origin of these enzymes. Only weak relationships between accessory gland markers and catalase-like activity suggested a multi-glandular source of this enzyme. There was no relationship between the activity of any of the enzymes in the IVF patients with their fertilization rates in vitro or the establishment of pregnancy after IVF. Nor was there any correlation of enzyme activity with the morphology and percentage of motile spermatozoa in semen or with the percentage motility of spermatozoa immediately after swim-up or after overnight incubation. These findings suggest that the protective enzymes in the seminal plasma are contributed largely by the prostate and little by the epididymis, and that in most cases of IVF, they have no major influence on the outcome.   相似文献   
9.
10.
The effects of in vivo physiologic doses of vasopressin and 1-deamino-8-D-arginine vasopressin (DDAVP) on the cyclic AMP content of plasma, urine, and renal papillary tissue were determined in the ADH-deficient Brattleboro rat. During clearance studies, plasma cyclic AMP concentrations and both total and nephrogenous urinary cyclic AMP excretion in vasopressin- and DDAVP-treated rats were similar to the values in time-matched controls. In contrast, in situ renal papillary cyclic AMP content was higher (P less than 0.001) in both vasopressin- (35.7 +/- 3.6 pmol/mg protein) and DDAVP- (29.7 +/- 2.2 pmol/mg protein) treated rats compared to controls (15.1 +/- 1.3 pmol/mg protein). Endogenous stimulation of vasopressin by dehydration in normal rats increased both papillary cyclic AMP content (27.1 +/- 2.7 pmol/mg protein) and urine osmolality, whereas no change in papillary cyclic AMP was observed following dehydration in Brattleboro rats (13.6 +/- 0.8 pmol/mg protein) despite an increase in urine osmolality. The results demonstrate that changes in cyclic AMP following in vivo vasopressin are best demonstrated by measurement of in situ cyclic AMP content of the renal papilla, whereas total urinary cyclic AMP and nephrogenous cyclic AMP are not useful indices of tubular sensitivity to this hormone.  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