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   1634篇
  免费   158篇
  国内免费   2篇
耳鼻咽喉   10篇
儿科学   82篇
妇产科学   73篇
基础医学   224篇
口腔科学   32篇
临床医学   223篇
内科学   259篇
皮肤病学   48篇
神经病学   280篇
特种医学   54篇
外科学   149篇
综合类   15篇
一般理论   1篇
预防医学   150篇
眼科学   8篇
药学   144篇
肿瘤学   42篇
  2023年   10篇
  2021年   27篇
  2020年   19篇
  2019年   27篇
  2018年   29篇
  2017年   18篇
  2016年   31篇
  2015年   32篇
  2014年   36篇
  2013年   47篇
  2012年   66篇
  2011年   84篇
  2010年   44篇
  2009年   39篇
  2008年   71篇
  2007年   76篇
  2006年   71篇
  2005年   76篇
  2004年   52篇
  2003年   68篇
  2002年   64篇
  2001年   66篇
  2000年   57篇
  1999年   56篇
  1998年   23篇
  1997年   18篇
  1996年   16篇
  1995年   21篇
  1992年   42篇
  1991年   48篇
  1990年   47篇
  1989年   39篇
  1988年   35篇
  1987年   17篇
  1986年   30篇
  1985年   22篇
  1984年   19篇
  1983年   19篇
  1982年   13篇
  1981年   16篇
  1980年   10篇
  1979年   22篇
  1978年   17篇
  1977年   12篇
  1976年   12篇
  1974年   17篇
  1973年   10篇
  1972年   19篇
  1971年   9篇
  1970年   11篇
排序方式: 共有1794条查询结果,搜索用时 15 毫秒
31.
The neuropathological substrates of dementia and depression were evaluated in 30 patients with cerebrovascular disease and significant cognitive impairment (VaD), with a particular focus on patients with small infarct volumes (<15 ml). VaD patients with small infarct volumes had a similar degree of cognitive impairment to those with larger infarct volumes (>15 ml) but were significantly more likely to be depressed and to have areas of microinfarction. A review of individual cases with small infarct volumes suggested that the combination of microinfarction, diffuse white matter disease and perivascular changes, or the overlap of neurodegenerative pathologies and microvascular changes were particularly important. Microinfarction was also significantly associated with major depression.  相似文献   
32.
Most complications related to thoracoabdominal aortic reconstruction stem from ischemia-induced injury to the viscera, kidneys, and spinal cord. In addition to adjunctive methods designed to minimize metabolic demands of the spinal cord during aortic cross-clamping, a variety of extracorporeal techniques have been developed that provide supplemental blood flow to vital end organs during the period of clamp-induced ischemia. These techniques represent a broad range of design complexities and command significant operator expertise to optimize their benefit. This section briefly describes commonly used extracorporeal circulation methods in thoracoabdominal aortic surgery.  相似文献   
33.
34.
Early secretory and endoplasmic reticulum (ER)-localized proteins that are terminally misfolded or misassembled are degraded by a ubiquitin- and proteasome-mediated process known as ER-associated degradation (ERAD). Protozoan pathogens, including the causative agents of malaria, toxoplasmosis, trypanosomiasis, and leishmaniasis, contain a minimal ERAD network relative to higher eukaryotic cells, and, because of this, we observe that the malaria parasite Plasmodium falciparum is highly sensitive to the inhibition of components of this protein quality control system. Inhibitors that specifically target a putative protease component of ERAD, signal peptide peptidase (SPP), have high selectivity and potency for P. falciparum. By using a variety of methodologies, we validate that SPP inhibitors target P. falciparum SPP in parasites, disrupt the protein’s ability to facilitate degradation of unstable proteins, and inhibit its proteolytic activity. These compounds also show low nanomolar activity against liver-stage malaria parasites and are also equipotent against a panel of pathogenic protozoan parasites. Collectively, these data suggest ER quality control as a vulnerability of protozoan parasites, and that SPP inhibition may represent a suitable transmission blocking antimalarial strategy and potential pan-protozoan drug target.  相似文献   
35.
36.
A dysfunctional ubiquitin proteasome system may be a mediating factor of disease progression in Lewy body dementia (LBD). The effects of proteasome inhibition using lactacystin and epoxomicin in primary neuronal culture were studied to assess the validity of this model to reflect the cortical pathology of LBD. Treatment of primary cortical neurons with 5???M lactacystin for 24?h led to a 38?% reduction in the levels of ??-III-tubulin (p?<?0.05), a 48?% reduction in the levels of synaptophysin (p?<?0.05) and a 74?% reduction in the levels of drebrin (p?<?0.01), when compared to controls. Results for epoxomicin were similar. The loss of neuronal protein occurred prior to any loss of mitochondrial activity or cell death. The results are reflective of the loss of synapses and the synaptic changes observed in LBD, which may be an early event in the neurodegeneration of LBD. The similarities with the pathological changes in LBD highlight the possibility that this model can potentially provide a platform to test novel treatments.  相似文献   
37.
38.
Introduction: People with dementia may be unable to verbally express pain and suffer from untreated pain. Use of analgesics in people with dementia has increased during the last decade, in particular opioid analgesics with high potential for adverse effects.

Areas covered: This article presents a systematic review of the current evidence for safety and tolerability of analgesic drugs from randomized controlled trials in people with dementia. Relevant trials were identified by a literature search in the EMBASE, MEDLINE, and Cochrane databases from inception to November 2018. The search included the main terms ‘dementia’ and ‘analgesic’ or their subterms, and was filtered to limit results to clinical trials.

Expert opinion: Although pain treatment is increasingly recognized as an important clinical issue in people with advanced dementia, there is currently a lack of evidence to support safety evaluations of commonly used analgesics in this group. To inform treatment decisions and enable care providers to appropriately monitor patients at risk of adverse effects, it is necessary to conduct well-designed clinical trials to investigate the relative efficacy and safety of analgesics in people with dementia, with particular emphasis on harmful effects of long-term opioid use as well as short-term use of nonsteroidal anti-inflammatory drugs.  相似文献   

39.
Many scholars have defined family life education (FLE), and some have differentiated it from other family‐related fields. For example, Doherty (1995) provided a definition of the boundaries between FLE and family therapy; however, we believe those criteria can be improved. We explore the professions of family life education, family therapy, and family case management using the questions why, what, when, for whom, and how? After examining these questions for each role, we introduce the domains of family practice to differentiate among them. The approach defines FLE and encourages appropriate collaboration among the fields. Suggestions are made for using this model for career exploration, reviewing job requirements to assess role consistency and clarity, and for determining the need for and appropriateness of referral and collaboration.  相似文献   
40.
Compliance with the consultant’s recommendations is one measure of the effectiveness of a consultation. A previous study showed that compliance was better when fewer recommendations were made. In the subsequent year, consultants were encouraged to limit their recommendations to five or fewer. Despite a significant decrease in the number of recommendations, compliance rates remained essentially unchanged (72%). Multivariate analysis demonstrated that the clinical severity of the patient’s disease and the number of associated problems, as well as the types of recommendations, were significant predictors of compliance. Compliance was best for recommendations involving medications (84%) and worst for recommendations involving diagnostic tests (62%). Compliance was also evaluated in the context of a surgeon’s view of the appropriateness of the recommendations. For recommendations felt to be essential to patient care the compliance rate was 75%, but it was only 44% for recommendations judged non-essential (p<0.001). The consulting internist should be aware that the surgeon’s view of the relevance of the recommendations to patient care needs may have an important effect on compliance. Received from the Departments of Medicine and Surgery, Cornell University Medical College, New York, New York. Dr. Ballard was a Henry J. Kaiser Foundation Fellow in General Internal Medicine. Dr. Gold is a Fellow in Cardio-Thoracic Surgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts. Dr. Charlson is a Henry J. Kaiser Family Foundation Faculty Scholar in General Internal Medicine.  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