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   5876篇
  免费   369篇
  国内免费   51篇
耳鼻咽喉   82篇
儿科学   247篇
妇产科学   78篇
基础医学   304篇
口腔科学   126篇
临床医学   1123篇
内科学   811篇
皮肤病学   92篇
神经病学   922篇
特种医学   104篇
外科学   435篇
综合类   455篇
一般理论   2篇
预防医学   961篇
眼科学   37篇
药学   326篇
  2篇
中国医学   63篇
肿瘤学   126篇
  2023年   146篇
  2022年   294篇
  2021年   361篇
  2020年   346篇
  2019年   397篇
  2018年   396篇
  2017年   305篇
  2016年   222篇
  2015年   187篇
  2014年   484篇
  2013年   599篇
  2012年   293篇
  2011年   427篇
  2010年   270篇
  2009年   269篇
  2008年   279篇
  2007年   196篇
  2006年   144篇
  2005年   114篇
  2004年   105篇
  2003年   83篇
  2002年   66篇
  2001年   61篇
  2000年   42篇
  1999年   34篇
  1998年   18篇
  1997年   33篇
  1996年   17篇
  1995年   19篇
  1994年   14篇
  1993年   15篇
  1992年   10篇
  1991年   4篇
  1990年   7篇
  1989年   6篇
  1988年   3篇
  1987年   3篇
  1986年   3篇
  1985年   3篇
  1984年   3篇
  1982年   2篇
  1981年   2篇
  1980年   2篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
  1976年   2篇
  1975年   2篇
  1974年   2篇
  1973年   2篇
排序方式: 共有6296条查询结果,搜索用时 15 毫秒
991.

BACKGROUND:

Tools are lacking to assess the individual risk of severe toxicity from chemotherapy. Such tools would be especially useful for older patients, who vary considerably in terms of health status and functional reserve.

METHODS:

The authors conducted a prospective, multicentric study of patients aged ≥70 years who were starting chemotherapy. Grade 4 hematologic (H) or grade 3/4 nonhematologic (NH) toxicity according to version 3.0 of the Common Terminology Criteria for Adverse Events was defined as severe. Twenty‐four parameters were assessed. Toxicity of the regimen (Chemotox) was adjusted using an index to estimate the average per‐patient risk of chemotherapy toxicity (the MAX2 index). In total, 562 patients were accrued, and 518 patients were evaluable and were split randomly (2:1 ratio) into a derivation cohort and a validation cohort.

RESULTS:

Severe toxicity was observed in 64% of patients. The Chemotherapy Risk Assessment Scale for High‐Age Patients (CRASH) score was constructed along 2 subscores: H toxicity and NH toxicity. Predictors of H toxicity were lymphocytes, aspartate aminotransferase level, Instrumental Activities of Daily Living score, lactate dehydrogenase level, diastolic blood pressure, and Chemotox. The best model included the 4 latter predictors (risk categories: low, 7%; medium‐low, 23%; medium‐high, 54%; and high, 100%, respectively; Ptrend < .001). Predictors of NH toxicity were hemoglobin, creatinine clearance, albumin, self‐rated health, Eastern Cooperative Oncology Group performance, Mini‐Mental Status score, Mini‐Nutritional Assessment score, and Chemotox. The 4 latter predictors provided the best model (risk categories: 33%, 46%, 67%, and 93%, respectively; Ptrend < .001). The combined risk categories were 50%, 58%, 77%, and 79%, respectively; Ptrend < .001). Bootstrap internal validation and independent sample validation demonstrated stable risk categorization and Ptrend < .001.

CONCLUSIONS:

The CRASH score distinguished several risk levels of severe toxicity. The split score discriminated better than the combined score. To the authors' knowledge, this is the first score systematically integrating both chemotherapy and patient risk for older patients and has a potential for future clinical application. Cancer 2011. © 2011 American Cancer Society.  相似文献   
992.
目的:调查和评价开展抗菌药物专项整治活动的干预对控制药占比的效果。方法:调查干预前后药占比、门诊抗菌药物使用率、住院患者抗菌药物使用率、抗菌药物使用强度和抗菌药物占全部药品金额的变化情况。结果:开展抗菌药物专项整治活动后,医院药占比下降5.79%,门诊抗菌药物使用率下降13.99%,住院患者抗菌药物使用率下降12.89%,抗菌药物使用强度下降20.15DDD,抗菌药物占全部药品金额比下降11.05%。结论:合理使用抗菌药物是控制药占比的有效手段。  相似文献   
993.
A Swedish web-based service (www.escreen.se) offers self-assessment and self-monitoring of alcohol and drug use via on-line screening with the Alcohol Use Disorders Identification Test (AUDIT) and the Drug Use Disorders Identification Test (DUDIT) as well as in-depth risk assessment using extended versions of both tests (Alcohol-E and DUDIT-E). Users receive individualized feedback concerning their alcohol and drug consumption and can follow their alcohol and drug use over time in personal diagrams and by writing in an electronic diary. This study describes user characteristics, service utilization patterns, and psychometric test properties for 2361 individuals who created a valid account over 20 months starting in February 2007. Problematic alcohol use according to AUDIT criteria was indicated for 67.4%, while 46.0% met DUDIT criteria for problematic drug use. Men and women accessed the service equally, with a mean age of 23 years. Internal consistency reliability figures were 0.90 for 1846 first-time AUDIT users and 0.97 for 1211 first-time DUDIT users; among 213 second-time AUDIT users reliability was 0.93, and 0.96 for 97 second-time DUDIT users. Internet-based alcohol and drug monitoring could function as a self-help tool or as a complement to substance abuse treatment.  相似文献   
994.
Obesity and related metabolic conditions are of epidemic proportions in most of the world, affecting both adults and children. The accumulation of lipids in the body in the form of white adipose tissue in the abdomen is now known to activate innate immune mechanisms. Lipid accumulation causes adipocytes to directly secrete the cytokines interleukin (IL) 6 and tumor necrosis factor α (TNFα), but also monocyte chemoattractant protein 1 (MCP-1), which results in the accumulation of leukocytes in fat tissue. This sets up a chronic inflammatory state which is known to mediate the association between obesity and conditions such as cardiovascular disease, type 2 diabetes, and cancer. There is also a substantial literature linking inflammation with risk for depression. This includes the observations that: (1) people with inflammatory diseases such as multiple sclerosis, cardiovascular disease, and psoriasis have elevated rates of depression; (2) many people administered inflammatory cytokines such as interferon α develop depression that is indistinguishable from depression in non-medically ill populations; (3) a significant proportion of depressed persons show upregulation of inflammatory factors such as IL-6, C-reactive protein, and TNFα; (4) inflammatory cytokines can interact with virtually every pathophysiologic domain relevant to depression, including neurotransmitter metabolism, neuroendocrine function, and synaptic plasticity. While many factors may contribute to the association between inflammatory mediators and depression, we hypothesize that increased adiposity may be one causal pathway. Mediational analysis suggests a bi-directional association between adiposity and depression, with inflammation possibly playing an intermediary role.  相似文献   
995.

Ethnopharmacological relevance

Rheum australe D. Don (Polygonaceae) has been commonly used in traditional medicine for a wide range of ailments related to the circulatory, digestive, endocrine, respiratory and skeletal systems as well as to infectious diseases.

Aim of the review

To provide the up-to-date information that is available on the botany, traditional uses, phytochemistry, pharmacology and toxicology of Rheum australe. Additionally, to highlight the possible uses of this species to treat different diseases and to provide a basis for future research.

Materials and methods

The present review covers the literature available from 1980 to 2011. The information was collected from scientific journals, books, theses and reports via a library and electronic search (Google Scholar, Web of Science and ScienceDirect).

Results

Ethnomedical uses of Rheum australe have been recorded from China, India, Nepal and Pakistan for 57 different types of ailments. The phytochemical studies have shown the presence of many secondary metabolites belonging to anthraquinones, stilbenes, anthrones, oxantrone ethers and esters, chromones, flavonoids, carbohydrate, lignans, phenols and sterols. Crude extracts and isolated compounds from Rheum australe show a wide spectrum of pharmacological activities, such as antidiabetic, anti-inflammatory, antifungal, antimicrobial, antioxidant, anticancer, hepatoprotective and immune-enhancing activities, as well as a usefulness for improving renal function.

Conclusion

Rheum australe has been widely used source of medicine for years without any adverse effects. Many studies have provided evidence for various traditional uses. However, there is a need for additional studies of the isolated compounds to validate the traditional uses in human models. The present review on the botany, traditional uses, phytochemistry and toxicity has provided preliminary information for further studies and commercial exploitations of the plant.  相似文献   
996.
张志华 《光明中医》2012,27(8):1617-1618
目的研究中西医结合治疗干燥综合征的临床效果。方法将76例干燥综合征患者随机分成两组,分别采用不同的治疗方法进行治疗,治疗后观察临床疗效、免疫球蛋白和血沉的变化情况。结果 两组的临床效果进行对比发现,治疗组在有效率和总的有效率明显高于对照组,比较有统计学差异(P<0.05);治疗组在治疗前后免疫球蛋白中IgA、IgG和血沉均明显下降,治疗前后比较有统计学差异(P<0.05);对照组在治疗前后IgG和血沉明显下降,治疗前后比较有统计学差异;两组直接治疗后治疗组的IgG、IgM和血沉明显低于对照组,比较有统计学差异(P<0.05)。结论中医治疗干燥综合征具有较好的疗效。  相似文献   
997.
We have developed and tested an Italian version of the Migraine Disability Assessment (MIDAS) questionnaire, an established instrument for assessing headache-related disability. A multistep process was used to translate and adapt the questionnaire into Italian, which was then tested on 109 Italian migraine without aura patients, 86 (78.9%) of whom completed the form a second time 21 days later. Overall MIDAS score had good test-retest reliability (Spearman's correlation 0.77), closely similar to that found in English-speaking migraineurs, and individual responses were also satisfactorily reliable. Internal consistency was good (Cronbach's alpha 0.7). These findings support the use of the MIDAS questionnaire as a clinical and research tool with Italian patients.  相似文献   
998.
Assessment of Anxiety and Depression in Adolescents with Mental Retardation   总被引:3,自引:0,他引:3  
This report examines the concurrent validity of different informant and self-report assessment instruments of psychopathology, both general and specific for anxiety and/or depression, in referred mentally retarded adolescents with a depressive and anxiety disorders, according to DSM IV criteria. A consecutive, unselected sample of 50 mildly and moderate mentally retarded adolescents (29 males and 21 females, aged 11.8 to 18 years, mean age 15.1) were assessed using standardized assessment techniques: Psychopathology Instrument for Mentally Retarded Adults (PIMRA) (informant version) (total score, affective and anxiety subscales), Child Behavior Checklist (CBCL) (informant version) (total score, internalizing and externalizing scores, anxiety-depression scale), Zung Self-Rating Depression Scale and Zung Self-Rating Anxiety Scale. Patterns of correlation among measures were calculated. PIMRA and CBCL total scores were closely intercorrelated. Internalizing and externalizing scores of CBCL were not intercorrelated, but they both correlated with CBCL and PIMRA total scores. Anxiety measures were positively correlated; they correlated with PIMRA and CBCL total scores, as well as with the internalizing score of CBCL. Depression measures were not correlated; their correlation with more general measures of psychopathology was weak. Clinical implications of these findings are discussed.  相似文献   
999.
BackgroundMindfulness interventions can improve psychological distress and quality of life (QoL) in cancer survivors. Few mindfulness programs for cancer recovery exist in Southeastern U.S. The primary objective of this study was to assess the feasibility of a modified mindfulness-based stress reduction (MBSR) program for breast cancer patients in Birmingham, Alabama. The secondary objective was to explore potential program effects on mindfulness skills and QoL.MethodsThis study was a prospective, quasi-experimental feasibility study conducted over 10 months at a university hospital. Feasibility was achieved if 80% of eligible patients screened enrolled in the study and 70% of enrolled patients attended all 8 program sessions. Effectiveness was estimated by changes in mindfulness and QoL indicators measured with validated scales administered at 3 time points and assessed with a non-parametric Friedman test. Sessions included meditation, yoga, and an attention practice called body scan. There were 3 groups of 2–5 patients.ResultsThe sample totaled 12 patients. Forty-four percent (12/27) of eligible patients enrolled in the study, and two out of 12 enrolled patients completed 8 program sessions, resulting in 16.7% (2/12) retention. However, more than half (66.7%) of participants completed at least 7 sessions. Between baseline and 8-week follow-up, patients demonstrated statistically significant improvements in distress, general wellbeing, and fatigue-related QoL.ConclusionsFeasibility objectives were not achieved. However, a majority of participants (66.7%) completed 7 of 8 program sessions. Program effects were promising for distress, fatigue, and wellbeing. Results warrant further research on MBSR-like programs for breast cancer patients in Alabama.  相似文献   
1000.
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