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   7917篇
  免费   393篇
  国内免费   56篇
耳鼻咽喉   113篇
儿科学   126篇
妇产科学   126篇
基础医学   1063篇
口腔科学   548篇
临床医学   534篇
内科学   1887篇
皮肤病学   151篇
神经病学   975篇
特种医学   198篇
外科学   1085篇
综合类   28篇
一般理论   4篇
预防医学   371篇
眼科学   175篇
药学   540篇
中国医学   34篇
肿瘤学   408篇
  2023年   84篇
  2022年   190篇
  2021年   315篇
  2020年   207篇
  2019年   256篇
  2018年   295篇
  2017年   176篇
  2016年   218篇
  2015年   267篇
  2014年   338篇
  2013年   394篇
  2012年   602篇
  2011年   686篇
  2010年   359篇
  2009年   299篇
  2008年   532篇
  2007年   491篇
  2006年   461篇
  2005年   402篇
  2004年   359篇
  2003年   324篇
  2002年   287篇
  2001年   75篇
  2000年   65篇
  1999年   63篇
  1998年   56篇
  1997年   37篇
  1996年   38篇
  1995年   28篇
  1994年   20篇
  1993年   24篇
  1992年   35篇
  1991年   34篇
  1990年   31篇
  1989年   27篇
  1988年   23篇
  1987年   18篇
  1986年   30篇
  1985年   22篇
  1984年   20篇
  1983年   22篇
  1982年   16篇
  1981年   9篇
  1980年   9篇
  1979年   13篇
  1978年   10篇
  1977年   11篇
  1972年   9篇
  1968年   6篇
  1966年   9篇
排序方式: 共有8366条查询结果,搜索用时 15 毫秒
991.

Background

Risk stratification of a syncopal episode is necessary to better differentiate patients needing hospitalization of those who can be safely sent home from the emergency department. Currently there are no strict guidelines from our Brazilian medical societies to guide the cardiologist that evaluate patients in an emergency setting.

Objectives

To analyze the criteria adopted for defining the need for hospitalization and compare them with the predictors of high risk for adverse outcome defined by the OESIL score that is already validated in the medical literature for assessing syncope.

Methods

A cross-sectional study of patients diagnosed with syncope during emergency department evaluation at our institution in the year 2011.

Results

Of the 46,476 emergency visits made in that year, 216 were due to syncope. Of the 216 patients analyzed, 39% were hospitalized. The variables associated with the need of hospital admission were - having health care insurance, previous known cardiovascular disease, no history of prior stroke, previous syncope and abnormal electrocardiograms during the presentation. Patients classified in OESIL scores of 0-1 had a greater chance of emergency discharge; 2-3 scores showed greater association with the need of hospitalization. A score ≥ 2 OESIL provided an odds ratio 7.8 times higher for hospitalization compared to score 0 (p <0.001, 95% CI:4,03-15,11). In approximately 39% no etiological cause for syncope was found and in 18% cardiac cause was identified.

Conclusions

Factors such as cardiovascular disease, prior history of syncope, health insurance, no previous stroke and abnormal electrocardiograms, were the criteria used by doctors to indicate hospital admission. There was a good correlation between the clinical judgment and the OESIL criteria for high risk described in literature.  相似文献   
992.
993.
994.
995.
996.
997.
998.
BackgroundThe itAlian pRospective Study on CANGrELOr (ARCANGELO) was aimed to assess the safety of using cangrelor during percutaneous coronary intervention (PCI) in patients with acute coronary syndromes (ACS) in the daily practice.HypothesisThe safety of cangrelor after the transition to oral P2Y12 inhibitors was evaluated as the incidence of bleeding outcomes in the 30 days following PCI according to postauthorization safety study guidelines.MethodsAdults with ACS who were treated with cangrelor in one of the 28 centers involved in the study. Patients who consented to participate were followed in the 30 days following their PCI. Bleedings (Bleeding Academic Research Consortium [BARC] classification), major adverse cardiac events (MACEs), and adverse events were recorded. The interim results at two‐thirds of the enrollment period are presented.ResultsA total of 17 bleedings were observed in the 320 patients who completed the study at this stage. All bleedings were classified as BARC Type 1–2, except for one case of Type 3a (vessel puncture site hematoma). Four patients experienced MACEs (2 acute myocardial infarctions, 1 sudden cardiac death, 1 noncardiovascular death due to respiratory distress, and multiorgan failure). None of the bleedings was rated as related to cangrelor.ConclusionsThe interim results of the ARCANGELO study provide a preliminary confirmation that the use of cangrelor on patients with ACS undergoing PCI is not associated with severe bleedings.  相似文献   
999.
Purpose: Bladder cancer is the 13th most common cause of cancer death with the highest lifetime cost for treatment of all cancers. This scoping review clarifies the available evidence on the role of a novel therapeutic approach called immunogenic cell death (ICD) in urothelial cancer of the bladder. Methods: In accordance with the recommendations of the Joanna Briggs Institute, we searched MEDLINE (Ovid), EMBASE, CENTRAL databases, and supplemented with manual searches through the conferences, Google scholar, and clinicaltrials.gov for published studies up to April 2022. We included literature that studied molecular mechanisms of ICD and the role of certain danger-associated molecular patterns (DAMPs) in generating ICD, safety and efficacy of different ICD inducers, and their contributions in combination with other urothelial cancer treatments. Results: Oncolytic viruses, radiotherapy, certain chemo/chemo radiation therapy combinations, photodynamic therapy, and novel agents were studied as ICD-inducing treatment modalities in the included studies. ICD was observed in vitro (murine or human urothelial carcinoma) in ten studies, eight studies were performed on mouse models (orthotopic or subcutaneous), and five clinical trials assessed patient response to ICD inducing agents. The most common studied DAMPs were Calreticulin, HMGB1, ATP, and Heat Shock Proteins (HSP) 70 and 90, which were either expressed on the cancer cells or released. Conclusion: ICD inducers were able to generate lasting antitumor immune responses with memory formation in animal studies (vaccination effect). In clinical trials these agents generally had low side effects, except for one trial, and could be used alone or in combination with other cancer treatment strategies in urothelial cancer patients.  相似文献   
1000.
Harmful algal blooms, in particular recurrent blooms of the dinoflagellate Alexandrium catenella, associated with paralytic shellfish poisoning (PSP), frequently limit commercial shellfish harvests, resulting in serious socio-economic consequences. Although the PSP-inducing species that threaten the most vulnerable commercial species of shellfish are very patchy and spatially heterogeneous in their distribution, the spatial and temporal scales of their effects have largely been ignored in monitoring programs and by researchers. In this study, we examined the spatial and temporal dynamics of PSP toxicity in the clam (Ameghinomya antiqua) in two fishing grounds in southern Chile (Ovalada Island and Low Bay). During the summer of 2009, both were affected by an intense toxic bloom of A. catenella (up to 1.1 × 106 cells L−1). Generalized linear models were used to assess the potential influence of different environmental variables on the field detoxification rates of PSP toxins over a period of 12 months. This was achieved using a four parameter exponential decay model to fit and compare field detoxification rates per sampling site. The results show differences in the spatial variability and temporal dynamics of PSP toxicity, given that greater toxicities (+10-fold) and faster detoxification (20% faster) are observed at the Ovalada Island site, the less oceanic zone, and where higher amounts of clam are annually produced. Our observations support the relevance of considering different spatial and temporal scales to obtain more accurate assessments of PSP accumulation and detoxification dynamics and to improve the efficacy of fisheries management after toxic events.  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