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   1005724篇
  免费   68412篇
  国内免费   2581篇
耳鼻咽喉   14149篇
儿科学   31996篇
妇产科学   28546篇
基础医学   141186篇
口腔科学   28525篇
临床医学   81486篇
内科学   209040篇
皮肤病学   22539篇
神经病学   79816篇
特种医学   38809篇
外国民族医学   337篇
外科学   154957篇
综合类   19615篇
一般理论   282篇
预防医学   75439篇
眼科学   22599篇
药学   71349篇
中国医学   2326篇
肿瘤学   53721篇
  2021年   8130篇
  2019年   8964篇
  2018年   13505篇
  2017年   9735篇
  2016年   10058篇
  2015年   11348篇
  2014年   15326篇
  2013年   23733篇
  2012年   33748篇
  2011年   35868篇
  2010年   20869篇
  2009年   18770篇
  2008年   32922篇
  2007年   35046篇
  2006年   34587篇
  2005年   34023篇
  2004年   32105篇
  2003年   30836篇
  2002年   30165篇
  2001年   44055篇
  2000年   45663篇
  1999年   38559篇
  1998年   10359篇
  1997年   9390篇
  1996年   9314篇
  1995年   8617篇
  1994年   8220篇
  1992年   29111篇
  1991年   27740篇
  1990年   27113篇
  1989年   25915篇
  1988年   24043篇
  1987年   23631篇
  1986年   22734篇
  1985年   21551篇
  1984年   16105篇
  1983年   13712篇
  1982年   8203篇
  1979年   14856篇
  1978年   10378篇
  1977年   8782篇
  1976年   8316篇
  1975年   9176篇
  1974年   10956篇
  1973年   10482篇
  1972年   9898篇
  1971年   9182篇
  1970年   8828篇
  1969年   8284篇
  1968年   7918篇
排序方式: 共有10000条查询结果,搜索用时 296 毫秒
21.

Background and objectives

A prompt and effective management of trauma patient is necessary. The aim of this case report is to highlight the importance of intraoperative echocardiography as a useful tool in patients suffering from refractory hemodynamic instability no otherwise explained.

Case report

A 41 year‐old woman suffered a car accident. At the emergency department, no abnormalities were found in ECG or chest X‐ray. Abdominal ultrasound revealed the presence of abdominal free liquid and the patient was submitted to urgent exploratory laparotomy. Nevertheless, she persisted suffering arterial hypotension and metabolic acidosis. Looking for the reason of her hemodynamic instability, intraoperative transthoracic echocardiography was performed, finding out the presence of pericardial effusion. Once the cardiac surgeon extracted pericardial clots, patient's situation improved clinically and analytically.

Conclusion

Every anesthesiologist should be able to use the intraoperative echocardiography as an effective tool in order to establish the appropriate measures to promote the survival of patients suffering severe trauma.  相似文献   
22.
Chondrocytes are the main cells in the extracellular matrix (ECM) of articular cartilage and possess a highly differentiated phenotype that is the hallmark of the unique physiological functions of this specialised load-bearing connective tissue. The plasma membrane of articular chondrocytes contains a rich and diverse complement of membrane proteins, known as the membranome, which defines the cell surface phenotype of the cells. The membranome is a key target of pharmacological agents and is important for chondrocyte function. It includes channels, transporters, enzymes, receptors, and anchors for intracellular, cytoskeletal and ECM proteins and other macromolecular complexes. The chondrocyte channelome is a sub-compartment of the membranome and includes a complete set of ion channels and porins expressed in these cells. Many of these are multi-functional proteins with “moonlighting” roles, serving as channels, receptors and signalling components of larger molecular assemblies. The aim of this review is to summarise our current knowledge of the fundamental aspects of the chondrocyte channelome, discuss its relevance to cartilage biology and highlight its possible role in the pathogenesis of osteoarthritis (OA). Excessive and inappropriate mechanical loads, an inflammatory micro-environment, alternative splicing of channel components or accumulation of basic calcium phosphate crystals can result in an altered chondrocyte channelome impairing its function. Alterations in Ca2+ signalling may lead to defective synthesis of ECM macromolecules and aggravated catabolic responses in chondrocytes, which is an important and relatively unexplored aspect of the complex and poorly understood mechanism of OA development.  相似文献   
23.
24.
25.
We report a Chinese family with members affected by epidermolytic ichthyosis (EI), caused by KRT gene mutations. The proband was a 14‐year‐old boy who had simultaneous appearance of nephroblastoma and epidermolytic ichthyosis (EI). Both the patient and his mother exhibited the specific clinical and pathological manifestations of EI. We analysed all exons and flanking sequences of the KRT1 and KRT10 genes using PCR, and found that the proband and his mother had a G>C transition at nucleotide position 1432 in exon 7 of KRT1, resulting in an amino acid substitution of glutamate (GAA) to glutamine (CAA) at codon 478 (E478Q). The KRT10 gene had no mutations.  相似文献   
26.
Henna, derived from a combination of natural leaves and coloring additives, is a common decorative dye traditionally used in many Islamic religious celebrations. Para‐phenylenediamine (PPD), a major component of black henna tattoo, is a strong sensitizer and common allergen. We report a case of severe connubial allergic contact dermatitis after black henna heterotransfer in a girl.  相似文献   
27.
Owing to the frequent incidence of blast-induced traumatic brain injury (bTBI) in recent military conflicts, there is an urgent need to develop effective therapies for bTBI-related pathologies. Blood-brain barrier (BBB) breakdown has been reported to occur after primary blast exposure, making restoration of BBB function and integrity a promising therapeutic target. We tested the hypothesis that treatment with dexamethasone (DEX) after primary blast injury potentiates recovery of an in vitro BBB model consisting of mouse brain endothelial cells (bEnd.3). DEX treatment resulted in complete recovery of transendothelial electrical resistance and hydraulic conductivity 1 day after injury, compared with 3 days for vehicle-treated injured cultures. Administration of RU486 (mifepristone) inhibited effects of DEX, confirming that barrier restoration was mediated by glucocorticoid receptor signaling. Potentiated recovery with DEX treatment was accompanied by stronger zonula occludens (ZO)-1 tight junction immunostaining and expression, suggesting that increased ZO-1 expression was a structural correlate to BBB recovery after blast. Interestingly, augmented ZO-1 protein expression was associated with specific upregulation of the α+ isoform but not the α isoform. This is the first study to provide a mechanistic basis for potentiated functional recovery of an in vitro BBB model because of glucocorticoid treatment after primary blast injury.  相似文献   
28.
Acne vulgaris (acne) is a chronic inflammatory disease of the sebaceous gland, characterized by follicular hyperkeratinization, excessive colonization by Propionibacterium acnes (Pacnes) as well as immune reactions and inflammation. Despite an armamentarium of topical treatments available including benzoyl peroxide, retinoids and azelaic acid, topical antibiotics in monotherapies, especially erythromycin and clindamycin, are still used in Europe to treat acne. This intensive use led to antimicrobial‐resistant P. acnes and staphylococci strains becoming one of the main health issues worldwide. This is an update on the current topical acne treatments available in Europe, their mechanism of action, their potential to induce antimicrobial resistance and their clinical efficacy and safety.  相似文献   
29.
30.
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