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   25617篇
  免费   1786篇
  国内免费   48篇
耳鼻咽喉   187篇
儿科学   868篇
妇产科学   594篇
基础医学   3398篇
口腔科学   255篇
临床医学   3855篇
内科学   4478篇
皮肤病学   496篇
神经病学   2598篇
特种医学   457篇
外科学   2628篇
综合类   211篇
一般理论   41篇
预防医学   3412篇
眼科学   402篇
药学   1575篇
中国医学   20篇
肿瘤学   1976篇
  2024年   31篇
  2023年   246篇
  2022年   352篇
  2021年   774篇
  2020年   571篇
  2019年   746篇
  2018年   889篇
  2017年   656篇
  2016年   692篇
  2015年   703篇
  2014年   1029篇
  2013年   1485篇
  2012年   2213篇
  2011年   2295篇
  2010年   1212篇
  2009年   1061篇
  2008年   1780篇
  2007年   1877篇
  2006年   1703篇
  2005年   1585篇
  2004年   1438篇
  2003年   1258篇
  2002年   1239篇
  2001年   120篇
  2000年   111篇
  1999年   137篇
  1998年   217篇
  1997年   175篇
  1996年   132篇
  1995年   110篇
  1994年   109篇
  1993年   95篇
  1992年   48篇
  1991年   40篇
  1990年   33篇
  1989年   28篇
  1988年   15篇
  1987年   18篇
  1986年   22篇
  1985年   19篇
  1984年   29篇
  1983年   14篇
  1982年   27篇
  1981年   19篇
  1980年   12篇
  1979年   13篇
  1977年   10篇
  1976年   13篇
  1975年   8篇
  1974年   8篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
13.
Sickle cell disease (SCD) is a genetic disorder that is most prevalent among those of African American and Mediterranean descent. Hemoglobin SS is the most severe form of SCD and carries an increased risk for stroke. Although the initial treatment for stroke is an exchange transfusion, the use of routine, chronic transfusion therapy (CTT) has been shown to help prevent this neurological injury. The treatment plan is rigorous and time consuming, both of which impact one's quality of life (QoL). The purpose of this study was to explore QoL, from the child's perspective, as it is affected by CTT Semistructured interviews were performed on 10 children undergoing CIT: Five themes emerged from the data: (a) pain, (b) school issues, (c) disease knowledge, (d) transfusion therapy, and (e) having a stroke. Data from this study reveal that CTT does have an impact on QoL. This information is important to share with those making CTT treatment decisions.  相似文献   
14.
The significance of anticardiolipin antibodies (ACAs) prior to renal transplantation is unclear. We studied a cohort of 337 patients who underwent renal transplantation from 1996 to 2001. Follow-up continued until allograft loss, patient death or 31 December 2002. The primary outcome was a composite endpoint of death-censored allograft loss or a 25% reduction in estimated glomerular filtration rate (GFR) from 1-month post-transplant. Secondary outcomes were allograft loss, a 25% reduction in GFR, acute rejection and creatinine at 1 year. IgG and IgM ACA titers were positive (> or =15) in 18.1% of recipients. There were no significant differences at baseline between recipients, except coumadin therapy in those with positive ACA titers (20% vs. 7.4%). Post-transplant, there was no increase in the primary outcome in ACA-positive patients, even after adjustment for anticoagulation with coumadin (HR = 1.42 [0.68, 2.96]). There was no difference in secondary outcomes between those with or without positive titers. Two of five patients with very high titers (>50) who were not anticoagulated had early graft loss. A positive ACA titer prior to kidney transplantation was not associated with inferior renal outcomes after transplantation, although more research is required to address the prognostic significance of very high ACA titers.  相似文献   
15.
Clinician diagnoses of conduct disorder (CD) were compared to the diagnoses of CD generated by a structured interview against an observed criterion. Participants were 534 youth from a large residential program in the Midwest for delinquent youth. Rates of in-program CD behaviors were gathered from staff observations of the youth over a 9-month time period. Youth diagnosed with CD by the Diagnostic Interview Schedule for Children (DISC) displayed significantly more CD behaviors in the first 6 months of treatment compared to both youth without an externalizing disorder and youth diagnosed with CD by a clinician. Youth diagnosed with CD by a clinician had rates of CD identical to youth without an externalizing disorder. Clinicians may have weighted contextual information more heavily, as this group was significantly more likely to have an arrest record. Results support the use of structured interviews and provide evidence that typical clinician diagnoses may lack adequate validity.  相似文献   
16.
Forty normal one-month-old infants were randomly assigned to a breast-like nipple (Healthflow) bottlefeeding or a standard nipple (Evenflo) bottlefeeding group for one 20-minute feeding by the infants' mothers. The data suggested that the mothers' bottlefeeding behaviors did not differ, but the infants who fed on the breast-like nipples spent less time asleep, more time awake and active and less time fussing and crying. In addition, the vagal tone of that group decreased more during bottlefeeding and increased more after the feeding, suggesting that the breast-like nipple bottlefeedings were more similar to breastfeedings (vagal tone being lower during breastfeeding and higher after breastfeeding versus bottlefeeding). Because many women who breastfeed return to work, bottlefeeding that more closely approximate breastfeedings may ease this transition and may provide more effective supplemental feedings for the breastfed infants.  相似文献   
17.
The present study examined dichotomies potentially relevant to parentchild and interparent agreement in the assessment of internalizing problems in youngsters. Specifically, 98 children and their parents completed the Daily Life Stressors Scale or a variant to examine child ratings of daily stress, parent ratings of their children's daily stress, and parent predictions of how their children would self-rate their stress. In addition, a distinction was made between subscores of negative affectivity and stressful life events. Results indicated moderate parent-child and interparent agreement, with the latter somewhat more influenced by a negative affectivity-stressful events dichotomy. Parent-child agreement appeared more enhanced for items involving more parental contact. Implications of these data for future research are discussed.  相似文献   
18.
Alpha power (8–12 Hz) was monitored over the frontal, temporal, parietal and occipital lobes of the left and right cerebral hemispheres while participants mentally rotated three-dimensional shapes to match a specified target. By comparing the activational patterns generated during three experimental conditions, each designed to systematically isolate the involvement of the various subcomponents comprising this mental rotation task, it was suggested that the right frontal lobe mediates encoding and comparison/decision processes, while the left parietal and the left temporal region appear most involved in the generation of images and their mental rotation. A preliminary model describing the cooperative interaction of these cortical regions during mental rotation tasks is proposed.  相似文献   
19.
OBJECTIVE: Several papers have reported higher prevalence of diabetes mellitus (DM) type 2 in patients suffering from bipolar disorder (BD). The possible links between these 2 disorders include treatment, lifestyle, alterations in signal transduction, and possibly, a genetic link. To study this relation more closely, we investigated whether there are any differences in the clinical characteristics of BD patients with and without DM. METHOD: We compared the clinical data of 26 diabetic and 196 nondiabetic subjects from The Maritime Bipolar Registry. Subjects were aged 15 to 82 years, with psychiatric diagnoses of BD I (n = 151), BD II (n = 65), and BD not otherwise specified (n = 6). The registry included basic demographic data and details on the clinical course of bipolar illness, its treatment, and physical comorbidity. In a subsequent analysis using logistic regression, we examined the variables showing differences between groups, with diabetes as an outcome variable. RESULTS: The prevalence of DM in our sample was 11.7% (n = 26). Diabetic patients were significantly older than nondiabetic patients (P < 0.001), had higher rates of rapid cycling (P = 0.02) and chronic course of BD (P = 0.006), scored lower on the Global Assessment of Functioning Scale (P = 0.01), were more often on disability for BD (P < 0.001), and had higher body mass index (P < 0.001) and increased frequency of hypertension (P = 0.003). Lifetime history of treatment with antipsychotics was not significantly associated with an elevated risk of diabetes (P = 0.16); however, the data showed a trend toward more frequent use of antipsychotic medication among diabetic subjects. CONCLUSIONS: Our findings suggest that the diagnosis of DM in BD patients is relevant for their prognosis and outcome.  相似文献   
20.
This paper describes a study in which 70 elderly patients were assessed for risk factors in their medication regimen They were separated into three study groups, including two levels of teaching intervention focused on the home medication administration system, and a control group The intervention utilizing a follow-up telephone call demonstrated a significant change in risk-related behaviours such as verbalization of the regimen, congruence between instructions and usage of medications, and taking of medicines not currently prescribed or over-the-counter  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