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   27667篇
  免费   1717篇
  国内免费   193篇
耳鼻咽喉   132篇
儿科学   804篇
妇产科学   1075篇
基础医学   1684篇
口腔科学   414篇
临床医学   4163篇
内科学   4763篇
皮肤病学   236篇
神经病学   1725篇
特种医学   854篇
外科学   5325篇
综合类   1264篇
现状与发展   2篇
一般理论   1篇
预防医学   4121篇
眼科学   294篇
药学   1135篇
  33篇
中国医学   125篇
肿瘤学   1427篇
  2024年   67篇
  2023年   1858篇
  2022年   2434篇
  2021年   2473篇
  2020年   2789篇
  2019年   1498篇
  2018年   1291篇
  2017年   1309篇
  2016年   1328篇
  2015年   1240篇
  2014年   2419篇
  2013年   1709篇
  2012年   1283篇
  2011年   942篇
  2010年   1332篇
  2009年   1262篇
  2008年   592篇
  2007年   588篇
  2006年   468篇
  2005年   325篇
  2004年   228篇
  2003年   225篇
  2002年   208篇
  2001年   242篇
  2000年   195篇
  1999年   212篇
  1998年   215篇
  1997年   148篇
  1996年   172篇
  1995年   164篇
  1994年   93篇
  1993年   56篇
  1992年   41篇
  1991年   44篇
  1990年   44篇
  1989年   41篇
  1988年   12篇
  1987年   1篇
  1986年   3篇
  1985年   5篇
  1984年   5篇
  1983年   4篇
  1982年   3篇
  1981年   1篇
  1980年   2篇
  1979年   1篇
  1978年   1篇
  1975年   3篇
  1973年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
《Nursing outlook》2022,70(2):219-227
BackgroundDespite the importance of adequate hospital nurse staffing, California is the only state with minimum nurse-to-patient ratio mandates. The health care workforce is historically “countercyclical”—exhibiting growth during economic recessions when employment in other sectors is shrinking.PurposeThis study was to examine how staffing mandates impact hospital nurse staffing during economic recessions.MethodWe compared hospital nurse staffing in California and in other states over 20 years to examine differences before and after the California mandate and, within the postmandate period, before, during, and after the Great Recession of 2008.FindingsStaffing differences increased during the postmandate period due to faster growth in California staffing compared to other states, except during the Great Recession, when staffing remained stable in California but declined in other states.DiscussionState legislators deliberating staffing mandates should consider the protective factor such policies provide during economic recessions and the implications for the quality and safety of care.  相似文献   
82.
BackgroundNowadays surgery remains the gold standard of treatment for tongue cancer. Via a more clear and precise terminology, the glossectomy classification by Ansarin et al. facilitates shared communication between surgeons, allowing comparison between published research and improving surgical practice and patient care. To establish the association of glossectomies, according to their classification by Ansarin et al. with overall survival (OS), disease-free survival (DSF), and cause-specific survival (CSS) in tongue cancer, we conducted a systemic retrospective study on 300 consecutive patients affected by primary oral tongue cancer and treated with surgery at the European Institute of Oncology, IRCCS (IEO).MethodsThree hundred patients with tongue squamous cell carcinoma and treated at the Division of Otorhinolaryngology and Head and Neck Surgery of the European Institute of Oncology, IRCCS were cataloged according to the glossectomy classification. OS, DFS, and CSS were compared by surgical treatments.ResultsOS-5yrs was 80% for the type I glossectomy group, 75% for type II, 65% for type III, and 35% for type IV-V. DFS-5yrs was 74%, 60%, 55%, and 27%, respectively for I, II, III, and IV-V glossectomy group; CSS-5yrs was 82%, 80%, 72%, and 48%, respectively for I, II, III, and IV-V glossectomy group (p < 0.01).ConclusionsThis study confirmed that the application of the glossectomy classification was statistically correlated with patients' oncological outcomes.  相似文献   
83.
《Journal of cardiac failure》2021,27(12):1472-1475
Excess deaths during the coronavirus disease 2019 (COVID-19) pandemic have been largely attributed to cardiovascular disease (CVD); however, patterns in CVD hospitalizations after the first surge of the pandemic have not well-documented. Our brief report, examining trends in health care avoidance documents that CVD hospitalizations decreased in Chicago before significant burden of COVID-19 cases or deaths and normalized during the first COVID-19 surge. These data may help to inform health care systems responses in the coming months while mobilizing vaccinations to the population at large.  相似文献   
84.
《Injury》2021,52(4):918-925
IntroductionThe origin and content of prolonged wound drainage (PWD) after arthroplasty remain uncertain. In this study, we performed the biochemical, biological and advanced proteomic analysis of the drainage fluid collected from PWD patients following hip hemiarthroplasty (HA).MethodsData of 28 patients who developed PWD after HA were prospectively analyzed. After examining the biochemical content of the drainage fluid collected on postoperative day 6, to find out if the drainage fluid was transudate or exudate, it was compared with the patient's serum values according to the Light criteria. Subsequently, biological and proteomic analyzes of both drainage fluid and serum were performed. The similarities and differences in terms of protein concentrations, protein identities were examined. In the drainage fluid, we analyzed lymph-specific proteins.Results16 patients with PWD were male (61.1%), 12 were female (38.9%), and the mean age of all patients was 79.64 ± 8.44 (65-95). Biochemical test results of the drainage fluid / serum were as follows: Total protein: 2.1 / 5.2 g/dl, albumin: 1.3 / 3.1 g/dl, lactate dehydrogenase (LDH): 121/324 U/l, cholesterol: 28/160 mg/dl, triglyceride: 37/122 mg/dl, sodium (Na): 140/ 140mg/dl, potassium (K): 4.1/ 4.1 mg/dl. pH of the drainage fluid was 7.6. According to these biochemical values, drainage fluid was classified as transudate. As a result of protein identification, fibrinogen beta chain, keratin type 1, creatine kinase M-type protein were detected in drainage fluid. Subsequent western analysis revealed that, gliseraldehyde-3-phosphate dehydrogenase (GAPDH) and beta actin antibody were detected in the drainage fluid but not in serum.ConclusionDespite the similarity in serum and transudative PWD fluid in terms of biochemical content, we found that when we carried out further proteomic analysis, PWD contains lymph-specific proteins. Unlike PWD, these proteins were not determined in serum. PWD fluid can be also called as lymphorrhea. PWD fluid with abundant proteins may also provide an appropriate environment for the growth of microorganisms.  相似文献   
85.
Background: Osteoarthritis (OA) is closely correlated with inflammation. It has been reported that lncRNA GAS5 plays an important role in inflammation, indicating the potential involvement of GAS5 in OA. This study was carried out to investigate the function of GAS5 in OA.Methods: Expression levels of GAS5 in synovial fluid from 45 OA patients and 45 healthy controls were measured by RT-qPCR. Cell transfections were performed to explore the potential interactions among GAS5, miR-146a, and Smad4 in chondrocytes. Lipopolysaccharide (LPS)-induced cell apoptosis after overexpression of GAS5, miR-146a, and Smad4 was analyzed by cell apoptosis assay.Results: GAS5 was downregulated in OA. Moreover, LPS treatment downregulated GAS5 in chondrocytes. Interaction between GAS5 could with miR-146a was predicted by bioinformatics analysis and further confirmed by RNA-RNA pulldown assay. However, overexpression of GAS5 and miR-146a did not affect the expression of each other. GAS5 overexpression increased Smad4 expression in chondrocytes. In contrast, miR-146a overexpression downregulated Smad4 in chondrocytes. Moreover, GAS5 and Smad4 overexpression inhibited LPS- induced chondrocytes apoptosis, while miR-146a overexpression played an opposite role and attenuated the effects of GAS5 and Smad4 overexpression on cell apoptosis.Conclusion: GAS5 might sponge miR-146a to upregulate Smad4, thereby suppressing LPS- induced chondrocytes apoptosis.  相似文献   
86.
ObjectiveCambodian Americans have complex, interrelated and persistent medical and mental health problems stemming from genocide and the social determinants of health. We examined changes in multiple domains of self-reported health outcomes from a diabetes prevention trial. Methods: Cambodian Americans with depression and high risk for diabetes (n = 188) were randomized to one of three community health worker interventions: lifestyle vs lifestyle plus medication therapy management vs social services. Assessments were at baseline, 12- and 15-months. Results: The typical participant was 55 years old, female, earned below $20,000 annually, and had 7 years of education. About one-third were taking antidepressant medication and over half had elevated depressive symptoms. Relative to social services, lifestyle and lifestyle plus medication therapy management were both similarly effective at increasing diabetes knowledge, nutrition habits, sleep quality and decreasing pain; 2) lifestyle alone was superior to social services for self-reported health; and, 3) all three groups showed improved anxiety and insomnia. There were no effects on physical activity or physical functioning. Conclusion: Community health worker interventions have multiple benefits beyond delaying diabetes. Practice Implications: Health promotion programs that are designed and delivered appropriately can impact even hard to reach and hard to treat groups.  相似文献   
87.
Background and objectivesRecent research has identified neighborhoods as an important contributor to later-life frailty. However, little is known about how neighborhood resources are associated with frailty trajectories over time, especially in developing countries. This study examines the impact of neighborhood physical and social resources on the trajectories of frailty over time among older people in China.Research design and methodsUsing the four waves of the China Health and Retirement Longitudinal Study (2011–2018), 5673 respondents aged 60 and above at baseline were included for analyses. Multilevel growth modeling was fitted to estimate the effects of neighborhood resources on frailty trajectories over a 7-year period, controlling for individual-level characteristics.ResultsOlder Chinese people who lived in neighborhoods with better basic infrastructures and a greater number of voluntary organizations were less frail at baseline. Accessible exercise facilities were associated with a lower initial level of frailty only among rural older adults, while higher community-level socioeconomic status (SES) was associated with a lower initial level of frailty only among urban older adults. Over the 7-year follow-up period, better basic infrastructures and accessible exercise facilities were associated with a slower increase rate of frailty scores among rural residents.Discussion and implicationsNeighborhood resources are important contributors to the level of frailty among older Chinese people. Our findings of significant urban-rural differences have important implications for designing and implementing infrastructure development and community building programs in rural and urban China.  相似文献   
88.
89.
90.
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