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   616篇
  国内免费   36篇
耳鼻咽喉   45篇
儿科学   343篇
妇产科学   234篇
基础医学   1145篇
口腔科学   83篇
临床医学   1120篇
内科学   1411篇
皮肤病学   187篇
神经病学   885篇
特种医学   152篇
外科学   721篇
综合类   72篇
一般理论   12篇
预防医学   983篇
眼科学   95篇
药学   453篇
中国医学   3篇
肿瘤学   625篇
  2023年   46篇
  2022年   53篇
  2021年   175篇
  2020年   115篇
  2019年   182篇
  2018年   196篇
  2017年   154篇
  2016年   159篇
  2015年   174篇
  2014年   267篇
  2013年   498篇
  2012年   578篇
  2011年   587篇
  2010年   341篇
  2009年   310篇
  2008年   496篇
  2007年   589篇
  2006年   507篇
  2005年   461篇
  2004年   438篇
  2003年   416篇
  2002年   383篇
  2001年   60篇
  2000年   41篇
  1999年   74篇
  1998年   94篇
  1997年   87篇
  1996年   68篇
  1995年   69篇
  1994年   60篇
  1993年   40篇
  1992年   49篇
  1991年   33篇
  1990年   36篇
  1989年   50篇
  1988年   47篇
  1987年   47篇
  1986年   44篇
  1985年   46篇
  1984年   46篇
  1983年   40篇
  1982年   43篇
  1981年   39篇
  1980年   34篇
  1978年   16篇
  1977年   19篇
  1976年   18篇
  1975年   16篇
  1974年   21篇
  1973年   22篇
排序方式: 共有8569条查询结果,搜索用时 46 毫秒
31.
32.
Anthracycline cardiotoxicity.   总被引:3,自引:0,他引:3  
Anthracycline drugs have been widely used as chemotherapeuticagents against a range of cancers, including sarcomas, carcinomas,leukaemias, and lymphomas. However, cardiotoxic effects, inparticular the development of cardiomyopathy, have limited theirclinical use. The observation of dose-dependent cardiotoxicityhas resulted in a recommended empirical dose limit of 450 mg/m2of body surface area. Age, gender, pre-existing heart disease,hypertension, and mediastinal irradiation have also been implicatedas factors contributing to the development of doxorubicin-associatedcardiomyopathy. However, cardiotoxicity may still occur at relativelylow levels of drug administration, even in individuals withno additional risk factors, and the onset may be delayed bymany years.1 More recently, the use of trastuzumab, a monoclonalantibody directed against the HER2 receptor, has been  相似文献   
33.
Melanophores were studied in tadpoles of the South African clawed toad, Xenopus laevis , during the first week after hatching (stages 46–49) at 25°C. The tadpoles had melanophores with dispersed melanosomes in the light and punctate melanophores in the dark in LD12:12. The melanophores remained punctate in constant dark and the melanosomes remained dispersed in constant light. Lights-out (in the light-time of LD12:12) caused the melanophores to become punctate, which occurred more quickly than the dispersion of melanosomes, which commenced when the lights were turned on (in the dark-time of LD12:12). Melanophores with dispersed melanosomes in tadpoles (in constant light) became punctate in response to a series of melatonin concentrations (0.2–5 ng/ml) in their bathing water irrespective of the time of day melatonin was administered. An image-analysis technique for assessing melanophore responses was tested.  相似文献   
34.
35.
36.
37.
Since Samuel Orton's (1937) assertion that dyslexia reflects abnormal brain organization, the relationship of learning disabilities to brain dysfunction has been the topic of considerable debate. Recently, learning-disabled individuals have been studied in conjunction with those known to have neurological dysfunction, in a search for common subtypes. In the present study, a population of 177 children, ages 9-0 to 14-0, were assessed on an augmented version of the Children's Halstead-Reitan Battery. One hundred twenty-nine Ss were learning-disabled, 37 of whom also had verified brain damage. The remaining 48 children had neither learning disabilities nor evidence of brain damage. Patterns of neuropsychological performance were determined using Tryon's clustering methods. The procedure yielded six subject clusters: (A) and (B)—children with low general intellectual ability; (C) children who are clumsy and lethargic; (D) children with language dysfunction; (E) children with faulty spatial orientation; and (F) children with no detectable neuropsychological deficits. These clusters were similar to those identified by investigators who have used other subject-clustering methods. Brain-damaged individuals were more prevalent in some clusters (e.g., A and B) than in others (e.g., E and F), and substantial numbers of learning disabled subjects were also found in clusters where brain-damaged individuals tended to cluster, indicating similar neuropsychological profiles. The cluster structure was validated by comparison with subtypes identified by other investigators, as well as by tests of association between clusters with exogenous factors (e.g., history of prematurity; seizures).  相似文献   
38.
The Diagnostic Interview for Personality Disorders (DIPD) is a semistructured interview of 252 questions that encompasses all 11 Axis II disorders described in the DSM-III. Its interrater reliability was assessed using a sample of 43 patients and its test-retest reliability was assessed using a separate sample of 54 patients. Adequate kappas were obtained in both situations for all disorders except schizoid personality disorder, which was never diagnosed. Interrater coefficients ranged from .52 to 1.0, with nine in the excellent range (κ > .75). Test-retest coefficients ranged from .46 to .85, with four in the excellent range. These results compara very favorably to those achieved using the other two Axis II interviews that have appeared in the literature, the Structured Interview for the DSM-III Personality Disorders (SIDP) and the Personality Disorder Examination (PDE).  相似文献   
39.
40.
OBJECTIVE: The goal of this study was to determine whether self-mutilators with personality disorders differ from nonmutilators with personality disorders in impulsivity, aggression, and other psychopathology and whether serotonergic dysfunction contributes to self-mutilation. METHOD: Twenty-six self-mutilators with personality disorders were matched to 26 control subjects with personality disorders for gender, age, education, axis I diagnosis of affective disorder, and axis II diagnosis of personality disorder. Numerous indexes of psychopathology as well as CSF 5-hydroxyindoleacetic acid (5-HIAA) levels and platelet imipramine binding sites (Bmax) and affinity (Kd) were determined. RESULTS: Self-mutilators had significantly more severe character pathology, had greater lifetime aggression, and were more antisocial than the control subjects. The self-mutilators scored higher on the Hamilton Rating Scale for Depression but not on the Beck Depression Inventory or the Beck Hopelessness Scale. The two groups did not differ on the Buss-Durkee Hostility and Guilt Inventory or on the Sensation Seeking Scale. The degree of self-mutilation was significantly correlated with impulsivity, chronic anger, and somatic anxiety. Both self-mutilation and impulsivity showed significant negative correlations with Bmax, although the two groups did not differ in CSF 5-HIAA levels or in platelet imipramine binding. CONCLUSIONS: The results demonstrate the contribution of severe character pathology, aggression, impulsivity, anxiety, and anger to self-mutilation and provide preliminary support for the hypothesis of underlying serotonergic dysfunction facilitating self-mutilation.  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