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   1949篇
  免费   137篇
  国内免费   4篇
耳鼻咽喉   26篇
儿科学   51篇
妇产科学   63篇
基础医学   221篇
口腔科学   59篇
临床医学   161篇
内科学   441篇
皮肤病学   116篇
神经病学   136篇
特种医学   55篇
外科学   336篇
综合类   6篇
预防医学   71篇
眼科学   44篇
药学   130篇
中国医学   13篇
肿瘤学   161篇
  2023年   24篇
  2022年   47篇
  2021年   80篇
  2020年   44篇
  2019年   51篇
  2018年   63篇
  2017年   51篇
  2016年   64篇
  2015年   63篇
  2014年   72篇
  2013年   77篇
  2012年   113篇
  2011年   111篇
  2010年   63篇
  2009年   55篇
  2008年   98篇
  2007年   87篇
  2006年   96篇
  2005年   91篇
  2004年   82篇
  2003年   91篇
  2002年   94篇
  2001年   44篇
  2000年   38篇
  1999年   26篇
  1998年   12篇
  1997年   12篇
  1996年   10篇
  1995年   12篇
  1994年   13篇
  1993年   8篇
  1992年   27篇
  1991年   20篇
  1990年   28篇
  1989年   22篇
  1988年   28篇
  1987年   17篇
  1986年   14篇
  1985年   21篇
  1984年   14篇
  1983年   14篇
  1980年   6篇
  1978年   6篇
  1975年   6篇
  1974年   10篇
  1972年   8篇
  1969年   7篇
  1968年   7篇
  1967年   7篇
  1966年   5篇
排序方式: 共有2090条查询结果,搜索用时 15 毫秒
991.
992.
This is a case report of a 5-year-old girl with congenital adrenal hyperplasia (CAH) who had clitoral hypertrophy and vagina opening at verumontanum between the bladder neck and external urethral sphincter. Female pseudohermaphroditism with CAH is the most common type of intersex problem seen in children. In females with this disorder, the internal genital organs are usually normal, but variable degrees of virilization can be observed externally. We discussed the indication of the surgical correction of ambiguous external genitalia in this syndrome in view of sexual function and cosmetic problems.  相似文献   
993.
We report a case of pyoderma gangrenosum (PG) associated with nasal septal perforation, pharyngeal ulcers and IgA paraproteinemia. A 28-year-old woman first developed painful undermined ulcers on her perianal, inguinal and axillary areas when she was 22 years old. Histological findings from the cutaneous ulcers showed dermal and epidermal infiltrate of neutrophils, which was compatible with PG. Laboratory examinations did not detect any associations of systemic diseases other than polyclonal IgA paraproteinemia. Nasal fiberscopy revealed septal perforation and multiple ulcers on her pharynx. The biopsy specimen from the pharyngeal ulcers showed a polymorphous cellular infiltrate without necrotizing vasculitis or granuloma. However, there were no atypical lymphocytes that are typically seen in nasal NK/T lymphoma. By immunohistochemical analysis, the infiltrated lymphocytes were proved to be T cells and Epstein-Barr virus encoded RNA (EBER) was not detected. No pulmonary or renal lesions resembling Wegener's granulomatosis were found. Taken together, the nasal septal perforation was considered as nasal involvement of PG.  相似文献   
994.

Purpose

To investigate the concentration and composition of N-glycans in plasma and vitreous samples obtained from patients with non-proliferative vitreoretinal diseases.

Methods

Plasma and vitreous samples were collected from 11 patients with idiopathic macular hole (MH) and 9 patients with epiretinal membrane (ERM). The samples were pretreated for enzymatic cleaving, and subsequently glycans released from proteins were captured on BlotGlyco H beads. Sialic acids were methyl-esterified. Processed glycans were tagged with aminooxy-functionalized peptide reagent (aoWR) and released from the beads, followed by detection by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The concentration and composition of N-glycans in the samples were assessed.

Results

Concentration of N-glycans in vitreous samples (132?±?29 pmol/100 μg protein) was significantly lower compared with those in plasma samples (714?±?29 pmol/100 μg protein, p?<?0.001). Predominant N-glycan in both plasma (39.7?±?1.1 %) and vitreous fluid (37.2?±?3.1 %) was identical, and the composition was presumed as [(Hex)2(HexNAc)2(NeuAc)2+ (Man)3(GlcNAc)2]. By contrast, the second-ranked N-glycan in vitreous samples (15.6?±?1.5 %) was the seventh in plasma (2.3?±?0.2 %).

Conclusions

The current data provide useful information on N-glycan profile in the vitreous fluid, which is distinct from that in the plasma.  相似文献   
995.
996.
997.
ObjectivePantothenic acid (PaA) is a vitamin that is an integral part of coenzyme A (CoA). CoA is an essential coenzyme in fat metabolism. The aim of this study was to determine whether PaA deficiency causes the accumulation of tissue fats and, if so, can refeeding of PaA decrease such accumulated fat.MethodsWeaning rats were fed the PaA-free diet for 30 d. Rats were then divided into two groups. One group was continuously fed the PaA-free diet, and the other was fed the PaA-containing diet for an additional 13 d. At the end of the experiment, liver fat and perinephric fat were weighed, and plasma triglyceride levels measured. An additional similar experiment was conducted in which rats consumed 15% ethanol instead of water.ResultsFat that accumulated by consuming the PaA-free diet for 30 d was decreased by consuming the PaA-containing diet for an additional 13 d. Ethanol feeding elicited much greater accumulation of liver, perinephric, and plasma fats if rats were fed the PaA-free diet. In such cases, administration of PaA could decrease the accumulated fat.ConclusionPaA deficiency causes fat accumulation, and readministration of PaA decreases the tissue fat in rats fed the pantothenic acid–free diet. Ethanol accelerated the accumulation of fat in rats fed the PaA-free diet. PaA could be beneficial for decreasing accumulated tissue fat.  相似文献   
998.
999.
The acute and chronic hemodynamic effects of the "basic regimen" for congestive heart failure (CHF), consisting of diuretics (furosemide) low salt diet and bed rest, was studied in 10 patients with CHF (all in NYHA class IV initially). In the acute stage, furosemide 80 mg i.v. effected rapid clinical improvement with reduction in ventricular filling pressures (VFP); however, no increase in cardiac-(CI) or stroke volume index (SVI) was observed. Subsequently, furosemide 80 mg/day, p.o. was administered for a mean of 30 days with the patients hospitalized on a low salt diet. During this period, their clinical condition was stable. The second hemodynamic study revealed that SVI increased (p less than 0.05) with reduction in VFP maintained. Next, low molecular weight dextran was infused to construct the Frank-Starling ventricular function curve (VFC) and this was compared with the VFC at the acute stage (during diuresis). As a whole, CI and SVI at the chronic stage were significantly increased (p less than 0.05) at equal pulmonary wedge pressures (PWP: mean 20 mmHg). Mean arterial pressure and systemic vascular resistance were decreased during the chronic stage. These findings suggest that the "basic CHF regimen" is effective on a chronic basis in improving left ventricular pump function through afterload and preload reduction, in addition to acute symptomatic relief due to a decrease in PWP.  相似文献   
1000.
Clinical and Experimental Nephrology - Factors affecting decline in renal function and cyst growth in patients with autosomal polycystic kidney disease (ADPKD) are not fully described, particularly...  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