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   4986篇
  免费   298篇
  国内免费   11篇
耳鼻咽喉   27篇
儿科学   169篇
妇产科学   145篇
基础医学   578篇
口腔科学   56篇
临床医学   857篇
内科学   823篇
皮肤病学   81篇
神经病学   500篇
特种医学   75篇
外科学   541篇
综合类   41篇
一般理论   7篇
预防医学   691篇
眼科学   60篇
药学   264篇
中国医学   7篇
肿瘤学   373篇
  2024年   4篇
  2023年   24篇
  2022年   29篇
  2021年   74篇
  2020年   61篇
  2019年   112篇
  2018年   119篇
  2017年   99篇
  2016年   99篇
  2015年   119篇
  2014年   175篇
  2013年   270篇
  2012年   404篇
  2011年   394篇
  2010年   235篇
  2009年   190篇
  2008年   339篇
  2007年   368篇
  2006年   355篇
  2005年   340篇
  2004年   338篇
  2003年   322篇
  2002年   266篇
  2001年   45篇
  2000年   40篇
  1999年   36篇
  1998年   41篇
  1997年   38篇
  1996年   41篇
  1995年   38篇
  1994年   33篇
  1993年   39篇
  1992年   25篇
  1991年   20篇
  1990年   21篇
  1989年   12篇
  1988年   11篇
  1987年   11篇
  1986年   11篇
  1985年   10篇
  1984年   7篇
  1983年   12篇
  1982年   8篇
  1981年   13篇
  1980年   10篇
  1976年   5篇
  1974年   6篇
  1973年   8篇
  1972年   3篇
  1971年   3篇
排序方式: 共有5295条查询结果,搜索用时 31 毫秒
51.
52.
CONTEXT: Chronic hepatitis C infection (CHCI) is an increasingly common problem, affecting about 2% of the US population. The cost and complexity of treatment and difficulties in communicating with the infected population are of concern to insurers and health planners. PURPOSE: To describe the clinical features of patients with CHCI in a rural Medicaid-covered population and to describe a method developed for treating CHCI in an underserved rural community. METHODS: We developed a disease management approach to patients with CHCI receiving insurance coverage through a Medicaid HMO in rural Oregon. A locally based multidisciplinary hepatitis committee was formed to develop a management protocol and a process for selecting patients for treatment. The committee met monthly to develop the treatment plan for individual patients. Day-to-day treatment was provided by a nurse under the supervision of the committee. FINDINGS: One hundred forty-three adults with CHCI were identified by their primary care physicians. About half the patients had a type 1 genotype. Treatment with pegylated interferon and ribavirin was completed on 21 persons, 11 (52%) of whom had a virologic cure. Problems with treatment toxicity were common. Patient satisfaction with the treatment by the nurse was high. CONCLUSIONS: CHCI is common in this rural, nonminority Medicaid-insured population. A locally based disease management model was developed that was well received by patients and was successful in delivering a high quality of care for people with CHCI in a rural area.  相似文献   
53.
Recent controversies surrounding the food industry and its contribution to diet-related illnesses provide fertile ground for re-examining where power lies in food systems. A review of the literature reveals a wide range of powerful actors, contradictory assessments about consumer power and numerous examples of producers and medical authorities expending significant effort to shape the criteria by which consumers exercise choice. Expertise from the fields of marketing, advertising, psychology and nutrition science has been marshalled for close to a century to create commodity contexts that are sympathetic to mass-produced foods. In the last quarter of the twentieth century, however, a new dynamic entered the equation: the battle between technical rationality and reflexive consumers. Consumers are questioning the credentials of foods and those who promote them and, simultaneously, are seeking hope and help from the food system. As a result, health claims have become a most important ingredient in the fight for competitive advantage. This paper describes how the re-embedding of trust in a food supply dominated by corporations is being attempted through the nutritionalization of the food supply. On the basis of two studies, the authors identify the actors, processes, ideological basis and points of resistance that comprise what they are terming an emergent ‘diets-making complex’ (DMC). By intensifying the influence of science and nutritional claims in dietary discourse, the DMC has the potential to circumscribe policy options about food and health, because appeals to individual health are obscuring a social view of the food supply.  相似文献   
54.
Information about the epidemiology of delirium has grown tremendously over the past 2 decades. However, methodological challenges have made this area of research difficult to study. Most studies have focused on the prevalence, risk factors, and course of delirium in elderly populations and acute medical and surgical settings. Growing evidence is showing that delirium is a neuropsychiatric syndrome that deserves more research and clinical attention. This article summarizes the current literature on the epidemiology of delirium and discusses some of the important methodological issues in conducting and interpreting research in this area.  相似文献   
55.
Evidence suggests that sleep disorders and sleep fragmentation are very common in nursing home residents. A variety of factors contribute to these sleeping difficulties, including age-related changes in sleep; the high prevalence of dementia, depression, medical illness and medications that affect sleep; and sleep disorders such as respiratory disturbance of sleep. Other important factors include common lifestyle characteristics in nursing home residents (such as inactivity, large amounts of time spent in bed, lack of bright light exposure, and poor sleep hygiene) and the disruptive night-time nursing home environment. Recent interventional studies suggest that improvement in the nursing home environment may be an important aspect of the management of sleeping difficulties. Assessment and management of sleeping problems in nursing home residents should involve comprehensive assessment and treatment of the multiple factors that can interfere with sleep. Residents who fail these interventions can be considered for treatment with sleeping medications. Unfortunately, there is little data on the effectiveness of sleeping medications and the specific management of sleep disorders in this setting. Future research should focus on clarifying the contribution of various environmental factors to sleep impairment, and the testing of these various interventions on sleep.  相似文献   
56.
PURPOSE: Cancer-testis genes mapping to the X chromosome have common expression patterns and show similar responses to modulators of epigenetic mechanisms. We asked whether cancer-testis gene expression occurred coordinately, and whether it correlated with variables of disease and clinical outcome of non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Tumors from 523 NSCLC patients undergoing surgery were evaluated for the expression of nine cancer-testis genes (NY-ESO-1, LAGE-1, MAGE-A1, MAGE-A3, MAGE-A4, MAGE-A10, CT7/MAGE-C1, SSX2, and SSX4) by semiquantitative PCR. Clinical data available for 447 patients were used to correlate cancer-testis expression to variables of disease and clinical outcome. RESULTS: At least one cancer-testis gene was expressed by 90% of squamous carcinoma, 62% of bronchioloalveolar cancer, and 67% of adenocarcinoma samples. Statistically significant coexpression was observed for 34 of the 36 possible cancer-testis combinations. Cancer-testis gene expression, either cumulatively or individually, showed significant associations with male sex, smoking history, advanced tumor, nodal and pathologic stages, pleural invasion, and the absence of ground glass opacity. Cox regression analysis revealed the expression of NY-ESO-1 and MAGE-A3 as markers of poor prognosis, independent of confounding variables for adenocarcinoma of the lung. CONCLUSIONS: Cancer-testis genes are coordinately expressed in NSCLC, and their expression is associated with advanced disease and poor outcome.  相似文献   
57.
58.
59.
Female cross-border migrants experience elevated risks for HIV, and migrants in South Africa may face additional risks due to the country’s underlying HIV prevalence. These risks may be mitigated by the receipt of social support. A behavioral risk-factor survey was administered using respondent-driven sampling. Multivariable regression models assessed the relationships between social support and two HIV outcomes: HIV serostatus and perceived HIV status. Low social support was not significantly associated with HIV status (aOR?=?1.03, 95?% CI 0.43–2.46), but was significantly related to a perception of being HIV positive (aPR?=?1.36, 95?% CI 1.04–1.78). Age, marital status, and education level were significantly associated with HIV serostatus. Illegal border-crossing, length of time in South Africa, anal sex, and transactional sex were significantly associated with aperception of being HIV positive. Future research should investigate how HIV risks and the receipt of social support change throughout the migration process.  相似文献   
60.
The purpose of the research was to conduct a quality indicator analysis of studies exploring the effects of antecedent exercise on self-stimulatory behaviors of individuals with autism spectrum disorders (ASD). Educational Resources Information Center (ERIC), Google Scholar, SPORTDiscus, PsychINFO, and PubMed/MedLine databases from 1980 to October 2010 and reference lists of included articles were searched. Twelve research studies employing group experimental (Gersten et al., 2005) or single-subject designs (Horner et al., 2005) met inclusion criteria. Each study was assessed for the presence and clarity of quality indicators. Group experimental and single-subject designs met 48% and 82% of quality indicators, respectively. This suggests that the effects of antecedent exercise on self-stimulatory behaviors of individuals with ASD is incomplete and claims of exercise being an evidence-based practice are premature. Several indicators were difficult to interpret or lacking clear definitions. Recommendations for clarifying and applying the quality indicators are offered.  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