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   2973篇
  免费   381篇
  国内免费   11篇
耳鼻咽喉   44篇
儿科学   94篇
妇产科学   66篇
基础医学   517篇
口腔科学   68篇
临床医学   367篇
内科学   526篇
皮肤病学   26篇
神经病学   364篇
特种医学   93篇
外科学   352篇
综合类   64篇
一般理论   3篇
预防医学   277篇
眼科学   82篇
药学   262篇
中国医学   1篇
肿瘤学   159篇
  2021年   41篇
  2020年   29篇
  2019年   48篇
  2018年   48篇
  2017年   29篇
  2016年   41篇
  2015年   40篇
  2014年   64篇
  2013年   106篇
  2012年   153篇
  2011年   160篇
  2010年   73篇
  2009年   66篇
  2008年   122篇
  2007年   141篇
  2006年   128篇
  2005年   104篇
  2004年   110篇
  2003年   84篇
  2002年   109篇
  2001年   98篇
  2000年   88篇
  1999年   92篇
  1998年   65篇
  1997年   44篇
  1996年   22篇
  1995年   49篇
  1994年   27篇
  1993年   50篇
  1992年   66篇
  1991年   65篇
  1990年   59篇
  1989年   69篇
  1988年   71篇
  1987年   72篇
  1986年   62篇
  1985年   66篇
  1984年   35篇
  1983年   47篇
  1981年   31篇
  1980年   32篇
  1979年   56篇
  1978年   31篇
  1977年   27篇
  1976年   26篇
  1975年   28篇
  1974年   31篇
  1973年   35篇
  1972年   32篇
  1970年   21篇
排序方式: 共有3365条查询结果,搜索用时 62 毫秒
71.
72.
Cannabis is the most commonly used illicit drug in Europe, and is generally regarded as having low acute toxicity. We present the findings of the first 6 months of data collection from the Euro-DEN project on presentations related to cannabis use to further understand the acute toxicity related to the use of cannabis. Data was extracted on clinical features, treatment and outcome from the Euro-DEN minimum dataset for all cases of acute recreational drug toxicity reported 1st October 2013 to 31st March 2014 for all cannabis-related presentations. Of 2198 presentations reported by 14 of the 16 Euro-DEN centres, 356 (16.2 %) involved cannabis either alone or together with other drugs/alcohol. There were 36 that involved lone use of cannabis (1.6 % of all presentations). Of the 35 non-fatal lone cannabis presentations, the most commonly reported features were neuro-behavioural (agitation/aggression 8 (22.9 %), psychosis 7 (20.0 %), anxiety 7 (20.0 %)) and vomiting 6 (17.1 %). Most patients (25, 71.4 %) received no treatment and 30 (85.7 %) were discharged/self-discharged from the ED. There was one fatality amongst these lone-cannabis cases: an 18-year-old male collapsed with an asystolic cardiac arrest whilst smoking cannabis and suffered hypoxic brain injury related to prolonged cardiac arrest. THC was detected in a urine sample taken at ED arrival; no other drugs were detected. Lone acute cannabis toxicity was typically associated with neuro-behavioural symptoms and vomiting. Although uncommon, severe toxicity including cardiovascular toxicity and death may be under-recognised, and it is important that Emergency Physicians are aware of this.  相似文献   
73.
Cognitive impairment is a common and debilitating feature of multiple sclerosis (MS) that has only recent gained considerable attention. Clinical neuropsychological studies have made apparent the multifaceted nature of cognitive troubles often encountered in MS and continue to broaden our understanding of its complexity. Radiographic studies have started to decipher the neuroanatomic substrate of MS‐related cognitive impairment and have shed light onto its pathogenesis. Where radiographic studies have been limited by inadequate resolution or non‐specificity, pathological studies have come to the fore. This review aims to provide an overview of the nature of cognitive impairment typically seen in MS and to explore the literature on imaging and pathological studies relevant to its evolution. In particular, the relative contributions of gray (ie, cerebral cortex, hippocampus, thalamus and basal ganglia) and white matter to MS‐related cognitive impairment will be discussed and the importance of interconnectivity between structures highlighted. The pressing need for longitudinal studies combining standardized neuropsychometric, paraclinical and radiographic outcomes obtained during life with post‐mortem tissue analysis after death is presented.  相似文献   
74.
A new analog of salmon calcitonin (N alpha-propionyl Di-Ala1,7,des-Leu19 sCT; RG-12851; here termed CTR), which lacks the ring structure of native calcitonin, was tested for biological activity in several in vitro and in vivo assay systems. The analog (CTR) and salmon calcitonin (sCT) stimulated kidney cell adenylate cyclase activity and inhibited bone resorption in organ cultures of fetal rat long bones with similar potencies and efficacies. Furthermore, CTR and sCT, at similar doses, induced comparable hypocalcemic responses in mice following sc injection or infusions. However, unlike sCT, CTR did not induce anorexia and weight loss in rats following sc injection. These data suggest that the ring structure of sCT may be important for the anorexigenic effect but is not required for effect on bone resorption or calcium homeostasis. Clinical studies appear warranted as, potentially, CTR might induce fewer side effects than does sCT.  相似文献   
75.

Background

Nurse-led services are expanding in Australia, yet current information about the scope and nature of these services is lacking. The need for more coordinated service planning and systematic evaluation prompted a scoping study to inform future development.

Aim

To provide a comprehensive profile of nurse-led services in the Queensland public health system.

Methods

A scoping study of 257 nurse-led services was conducted using an online survey distributed through each Hospital and Health Service in Queensland. Service level data were collected on structure, process and outcome evaluation, as well as enablers and barriers to sustainability of care delivery models.

Findings

There is a diverse and growing range of nurse-led services across the state that have evolved to meet the dynamic needs of their communities. Increasingly, registered nurses are rising to the challenge of providing equitable and accessible healthcare in ways that transcend traditional professional or care setting boundaries. The major challenges for sustainability were funding and resource limitations, particularly for developing service capacity to meet growing demands. There were also tensions around the need for ongoing negotiation and review of nurse-led services with medical and administrative stakeholders.

Discussion

Findings underscore the need for a modernised regulatory and policy framework to support sustainable nurse-led services and allow nurses to work to their full potential to optimise outcomes for the community.

Conclusion

Nurse-led services are the sleeping giant of healthcare reform in Australia. Now is the time for policy and practice changes that will realise the transformative potential of nurse-led care.  相似文献   
76.

Objectives

To assess the feasibility of conducting a trial of a psychoeducational intervention involving the provision of tailored information and coaching to improve management of a cancer-related symptom cluster (fatigue, pain, and sleep disturbance) and reduce symptom cluster impacts on patient health outcomes in the Vietnamese context and to undertake a preliminary evaluation of the intervention.

Methods

A parallel-group single-blind pilot quasi-experimental trial was conducted with 102 cancer patients in one Vietnamese hospital. The intervention group received one face-to-face session and two phone sessions delivered by a nurse one week apart, and the comparison group received usual care. Patient outcomes were measured at baseline before the chemotherapy cycle and immediately preceding the next chemotherapy cycle. Separate linear mixed models were used to evaluate the impact of the intervention on total symptom cluster severity, symptom scores, functional status, depressive symptoms, and health-related quality of life.

Results

The study design was feasible with a recruitment rate of 22.6% and attrition rate of 9.8%. Compared to the control group, the intervention group showed a significant reduction in symptom cluster severity, fatigue severity, fatigue interference, sleep disturbance, depression, and anxiety. Significant differences were not observed for pain severity, pain interference, functional status, and health-related quality of life. The intervention was acceptable to the study population, with a high attendance rate of 78% and adherence rate of 95.7%.

Conclusion

On the basis of the present study findings, future randomized controlled trials are needed to test the effectiveness of a symptom cluster psychoeducational intervention in Vietnam.  相似文献   
77.
78.
Six months of abstinence from alcohol is a commonly used criterion for liver transplantation eligibility for patients with alcoholic cirrhosis. There is limited evidence to document the validity of this criterion with regard to risk of alcoholism relapse. Ninety-one patients with alcoholic cirrhosis were interviewed for relapse risk using the High Risk Alcoholism Relapse (HRAR) Scale. The HRAR model can be used to predict relapse risk independent of duration of sobriety and therefore can be used to examine the validity of the 6 months of abstinence criteria in this clinical population. The two methods demonstrated poor to fair agreement. Agreement was highest with a cutoff allowing a 5% 6-month relapse risk when 79% agreement ( k = 0.56) was demonstrated between the two methods. Using the 6-month abstinence criterion alone disallows a significant number of candidates who have a low relapse risk based on their HRAR score. The validity of the 6-month abstinence criterion is supported somewhat by comparison with the HRAR model. However, use of the 6-month abstinence criterion alone forces a significant number of patients with a low relapse risk by HRAR to wait for transplant listing. A relapse risk model based on an estimate of alcoholism severity in addition to duration of sobriety may more accurately select patients who are most likely to benefit from liver transplantation.  相似文献   
79.
80.
Modifications to the newly developed tandem quadrupole Fourier-transform mass spectrometer have made it possible to record mass spectra on oligopeptides and small proteins in the mass range between 2 and 13 kDa.  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