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   23777篇
  免费   1639篇
  国内免费   136篇
耳鼻咽喉   351篇
儿科学   557篇
妇产科学   422篇
基础医学   3637篇
口腔科学   2190篇
临床医学   1835篇
内科学   5025篇
皮肤病学   674篇
神经病学   1766篇
特种医学   573篇
外国民族医学   1篇
外科学   2636篇
综合类   121篇
一般理论   11篇
预防医学   2424篇
眼科学   401篇
药学   1686篇
中国医学   190篇
肿瘤学   1052篇
  2023年   250篇
  2022年   270篇
  2021年   1033篇
  2020年   666篇
  2019年   887篇
  2018年   1016篇
  2017年   696篇
  2016年   841篇
  2015年   848篇
  2014年   1127篇
  2013年   1326篇
  2012年   1982篇
  2011年   2149篇
  2010年   1175篇
  2009年   885篇
  2008年   1411篇
  2007年   1396篇
  2006年   1155篇
  2005年   1121篇
  2004年   891篇
  2003年   797篇
  2002年   712篇
  2001年   385篇
  2000年   382篇
  1999年   285篇
  1998年   144篇
  1997年   99篇
  1996年   82篇
  1995年   73篇
  1994年   67篇
  1993年   59篇
  1992年   121篇
  1991年   115篇
  1990年   107篇
  1989年   77篇
  1988年   78篇
  1987年   91篇
  1986年   74篇
  1985年   65篇
  1984年   68篇
  1983年   52篇
  1982年   48篇
  1981年   26篇
  1979年   40篇
  1978年   31篇
  1977年   25篇
  1970年   26篇
  1969年   27篇
  1967年   27篇
  1966年   25篇
排序方式: 共有10000条查询结果,搜索用时 140 毫秒
1.
2.
3.
Purpose: Family psychosocial risk in pediatric oncology can be assessed using the Psychosocial Assessment Tool (PAT), a brief parent report screener based on the Pediatric Psychosocial Preventative Health Model (PPPHM; universal, targeted, and clinical). However, little is known about risk over the course of treatment and its association with medical and psychosocial healthcare utilization. Methods: Primary caregivers of children with cancer participated in this prospective multisite investigation, completing the PAT at diagnosis (T1; n = 396) and 6 months later (T2; n = 304). Healthcare utilization data were extracted from electronic health records. Results: The distribution of PPPHM risk levels at T1 and T2 was highly consistent for the samples. Two‐thirds of families remained at the same level of risk, 18% decreased and 16% increased risk level. Risk was not related to sociodemographic or treatment variables. The PAT risk score correlated with psychosocial contacts over the 6‐month period. Conclusions: Although the majority of families reported universal (low) risk on the PAT and were stable in their risk level over 6 months, reassessing risk is helpful in identifying those families who report higher level of risk during treatment than at diagnosis. PAT scores were related to psychosocial services that are provided to most but not all families and could be tailored more specifically to match risk and delivery of evidence‐based care.  相似文献   
4.
5.
6.
7.
8.

Objectives

To determine the incidence of incisional hernia (IH) in the extraction incision (EI) in colorectal resection for cancer. To analyze whether the location of the incision has any relationship with the incidence of hernias and whether mesh could be useful for prevention in high-risk patients.

Methods

Retrospective review of the colon and rectal surgery database from January 2015 to December 2016. Data were classified into 2 groups, transverse (TI) and midline incision (MI), and the latter was divided into 2 subgroups (mesh [MIM] and suture [MIS]). Patients were classified using the HERNIAscore. Hernias were diagnosed by clinical and/or CT examination.

Results

A total of 182 out of 210 surgical patients were included. After a median follow-up of 13.0 months, 39 IH (21.9%) were detected, 23 of which (13.4%) were in the EI; their frequency was lower in the TI group (3.4%) and in the MIM group (5.9%) than in the MIS group (29.5%; p = 0.007). The probability of developing IH in the MIS group showed an OR = 11.7 (95%CI: 3.3-42.0) compared to the TI group and 4.3 (IC 95%: 1.1-16.3) versus the MIM group.

Conclusions

The location of the incision is relevant to avoid incisional hernias. Transverse incisions should be used as the first option. When a midline incision is needed, a prophylactic mesh could be considered in high risk patients because it is safe and associated with low morbidity.  相似文献   
9.
10.
Melatonin, the main hormone produced by the pineal gland, is secreted in a circadian manner (24‐hr period), and its oscillation influences several circadian biological rhythms, such as the regulation of clock genes expression (chronobiotic effect) and the modulation of several endocrine functions in peripheral tissues. Assuming that the circadian synchronization of clock genes can play a role in the regulation of energy metabolism and it is influenced by melatonin, our study was designed to assess possible alterations as a consequence of melatonin absence on the circadian expression of clock genes in the epididymal adipose tissue of male Wistar rats and the possible metabolic repercussions to this tissue. Our data show that pinealectomy indeed has impacts on molecular events: it abolishes the daily pattern of the expression of Clock, Per2, and Cry1 clock genes and Pparγ expression, significantly increases the amplitude of daily expression of Rev‐erbα, and affects the pattern of and impairs adipokine production, leading to a decrease in leptin levels. However, regarding some metabolic aspects of adipocyte functions, such as its ability to synthesize triacylglycerols from glucose along 24 hr, was not compromised by pinealectomy, although the daily profile of the lipogenic enzymes expression (ATP‐citrate lyase, malic enzyme, fatty acid synthase, and glucose‐6‐phosphate dehydrogenase) was abolished in pinealectomized animals.  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