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   4856篇
  免费   301篇
  国内免费   18篇
耳鼻咽喉   39篇
儿科学   89篇
妇产科学   133篇
基础医学   700篇
口腔科学   172篇
临床医学   362篇
内科学   1122篇
皮肤病学   126篇
神经病学   381篇
特种医学   165篇
外科学   668篇
综合类   47篇
预防医学   252篇
眼科学   64篇
药学   399篇
中国医学   10篇
肿瘤学   446篇
  2023年   34篇
  2022年   67篇
  2021年   118篇
  2020年   68篇
  2019年   93篇
  2018年   102篇
  2017年   85篇
  2016年   111篇
  2015年   103篇
  2014年   140篇
  2013年   175篇
  2012年   323篇
  2011年   289篇
  2010年   159篇
  2009年   139篇
  2008年   260篇
  2007年   280篇
  2006年   249篇
  2005年   277篇
  2004年   238篇
  2003年   220篇
  2002年   217篇
  2001年   101篇
  2000年   107篇
  1999年   92篇
  1998年   41篇
  1997年   25篇
  1996年   32篇
  1994年   20篇
  1993年   18篇
  1992年   61篇
  1991年   72篇
  1990年   53篇
  1989年   83篇
  1988年   68篇
  1987年   69篇
  1986年   69篇
  1985年   52篇
  1984年   37篇
  1983年   37篇
  1981年   21篇
  1980年   18篇
  1979年   41篇
  1978年   24篇
  1977年   22篇
  1974年   19篇
  1972年   18篇
  1969年   26篇
  1968年   29篇
  1966年   27篇
排序方式: 共有5175条查询结果,搜索用时 15 毫秒
71.
72.
73.
74.
75.
Only 12% of Americans possess adequate health literacy skills. Among the populations cited with the lowest health literacy are those who experience chronic health conditions. A pilot health information literacy program was designed for parents of children with complex medical needs to help improve low health literacy in this population. The program targeted finding and determining trustworthy information online and was evaluated using a pre-post survey design. After the program parents’ confidence improved significantly in finding, interpreting, and judging quality online health information. These skills play an important role in promoting family-centered care and decreasing the burden on health care consumers.  相似文献   
76.
OBJECTIVE: To establish the generality of cerebrovascular pathology frequently observed with Alzheimer disease, we have assessed blood-brain barrier (BBB) integrity using the Alzheimer disease model Tg2576 mice in which cognitive deficits and neuritic plaque formation develop around 10-12 months of age. METHODS: We assessed BBB integrity using well-established methods involving albumin and Evans blue uptake and introduce the use of a novel perfusion protocol using succinimidyl ester of carboxyfluorescein diacetate. RESULTS: BBB permeability is increased in the cerebral cortex of 10-month-old Tg2576 mice preceding Alzheimer disease pathology presentation. Furthermore, when compared with their nontransgenic littermates, 4-month-old Tg2576 mice exhibit compromised BBB integrity in some areas of the cerebral cortex. An age-related increase in albumin uptake by the brains of Tg2576 mice, compared with nontransgenic mice, was also observed. These findings were supported by quantitative Evans blue analysis (p = 0.07, two-way analysis of variance). CONCLUSION: A breakdown of BBB was evident in young 4- to 10-month-old Tg2576 mice. Compromised barrier function could explain the mechanisms of Abeta entry into the brain observed in experimental Alzheimer disease vaccination models. Such structural changes to the BBB caused by elevated Abeta could play a central role in Alzheimer disease development and might define an early point of intervention for designing effective therapy against the disease.  相似文献   
77.
Diagnosis and management of acute obstetrical DIC   总被引:14,自引:0,他引:14  
Obstetrical disseminated intravascular coagulation (DIC) is usually a very acute, serious complication of pregnancy. The DIC diagnostic criteria in obstetrics (the obstetrical DIC score) help with making a prompt diagnosis and starting treatment early. These DIC diagnostic criteria, in which higher scores are given for clinical parameters than for laboratory parameters, have three components: (1) the underlying disease, (2) clinical symptoms, and (3) laboratory findings. It is justified that it is appropriate to initiate therapy for DIC when the obstetrical DIC score reaches 8 points or more before obtaining the results of coagulation tests. Management: (1) Control of the underlying disease: because prolongation of exposure to the triggering factors worsens DIC, it is important to eliminate the etiologic factors as rapidly as possible. Elimination of the cause of DIC can be easily performed in obstetrics, for example, by cesarean section. (2) Antithrombin (AT) therapy: AT monotherapy (1,500 to 3,000 units/day, 2 days) is preferably employed instead of heparin monotherapy or heparin-AT therapy because of the hemorrhagic side effects of heparin. (3) Synthetic serine protease inhibitors: continuous infusion ofgabexate mesilate (FOY) or nafamostat mesilate (FUT) is effective for DIC. Controlled multicenter trials showed a significant improvement not only in clinical response but also in platelet counts and prothrombin time (PT) in the AT group compared with the FOY group. (4) Activated protein C (APC) can inhibit thrombin generation and accelerate fibrinolytic activity. APC (5,000 to 10,000 units) is administered for 2 days in patients with placental abruption complicated by DIC. APC is a very safe, effective, and useful agent for the treatment of DIC.  相似文献   
78.
A 64-year-old man was admitted due to hypokalemia-related myopathy. He was heavy drinker. He felt the stress of alcohol withdrawal during his hospitalization. The patient suffered a cardiopulmonary arrest lasting approximately 5 minutes on the fifth hospital day. One day later, ST-segment elevation was observed in leads I, aV(L), and V(2-6). Emergent cardiac catheterization was performed for suspicion of acute myocardial infarction. Normal coronary arteries with anterior akinesis of the left ventricle were revealed during the procedure. The present case may be an atypical form of "Takotsubo cardiomyopathy" in which the left ventricular contraction is due to focal anterior wall motion abnormalities.  相似文献   
79.

Hinesol is a unique sesquiterpenoid isolated from the Chinese traditional medicine, Atractylodes lancea rhizome. In a previous study, we screened various natural products in human leukemia HL-60 cells and identified an essential oil fraction from A. lancea rhizome that exhibited apoptosis-inducing activity in these cells; hinesol was subsequently shown to be the compound responsible for this apoptosis-inducing activity. In this study, we describe the cytotoxic effects and molecular mechanisms of hinesol in HL-60 cells. The antitumor effect of hinesol was associated with apoptosis. When HL-60 cells were treated with hinesol, characteristic features of apoptosis, such as nuclear fragmentation and DNA fragmentation, were observed. These growth-inhibitory and apoptosis-inducing activities of hinesol in leukemia cells were much stronger than those of β-eudesmol, another compound isolated from the essential oil fraction. Furthermore, hinesol induced activation of c-Jun N-terminal kinase (JNK), but not p38, prior to the onset of apoptosis. These results suggested that hinesol induced apoptosis through the JNK signaling pathway in HL-60 cells. Therefore, hinesol may represent a novel medicinal drug having indications in the treatment of various cancers, including leukemia.

  相似文献   
80.
Rationale:In coronavirus disease 2019 (COVID-19) patients with acute respiratory distress syndrome refractory to optimal conventional management, we should consider the indication for veno-venous extracorporeal membrane oxygenation (V-V ECMO). Growing evidence indicates that COVID-19 frequently causes coagulopathy, presenting as hypercoagulation and incidental thrombosis. For these reasons, a multifactorial approach with several anticoagulant markers should be considered in the management of anticoagulation using heparin in COVID-19 patients on V-V ECMO.Patient concerns:A 48-year-old man was infected with COVID-19 with a worsening condition manifesting as acute respiratory distress syndrome.Diagnoses:He was refractory to conventional therapy, thus we decided to introduce V-V ECMO. We used heparin as an anticoagulant therapy for V-V ECMO and adjusted the doses of heparin by careful monitoring of the activated clotting time (ACT) and activated partial thromboplastin time (APTT) to avoid both hemorrhagic and thrombotic complications. We controlled the doses of heparin in the therapeutic ranges of ACT and APTT, but clinical hemorrhaging and profound elevation of coagulant marker became apparent.Interventions:Using thromboelastography (TEG; Haemonetics) in addition to ACT and APTT, we were able to clearly detect not only sufficient coagulability of COVID19 on V-V ECMO (citrated rapid thromboelastography-R 0.5 min, angle 75.5°, MA 64.0 mm, citrated functional fibrinogen-MA 20.7 mm) but also an excessive effect of heparin (citrated kaolin -R 42.7 min, citrated kaolin with heparinase 11.7 min).Outcomes:Given the TEG findings indicating an excessive heparin effect, the early withdrawal of ECMO was considered. After an evaluation of the patient''s respiratory capacity, withdrawal from V-V ECMO was achieved and then anticoagulation was stopped. The hemorrhagic complications and elevated thrombotic marker levels dramatically decreased.Lessons:TEG monitoring might be a useful option for managing anticoagulation in COVID-19 patients on V-V ECMO frequently showing a hypercoagulative state and requiring massive doses of heparin, to reduce both hemorrhagic and thrombotic complications.  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