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   92575篇
  免费   45318篇
  国内免费   266篇
耳鼻咽喉   1972篇
儿科学   4545篇
妇产科学   906篇
基础医学   18309篇
口腔科学   5419篇
临床医学   13799篇
内科学   26025篇
皮肤病学   8229篇
神经病学   14495篇
特种医学   3525篇
外科学   17029篇
综合类   155篇
现状与发展   1篇
一般理论   24篇
预防医学   5021篇
眼科学   1825篇
药学   7150篇
中国医学   1228篇
肿瘤学   8502篇
  2023年   104篇
  2022年   106篇
  2021年   1859篇
  2020年   5332篇
  2019年   11208篇
  2018年   10594篇
  2017年   11753篇
  2016年   12655篇
  2015年   12810篇
  2014年   12885篇
  2013年   13512篇
  2012年   6025篇
  2011年   5827篇
  2010年   9950篇
  2009年   6097篇
  2008年   3282篇
  2007年   2076篇
  2006年   2031篇
  2005年   1684篇
  2004年   1456篇
  2003年   1322篇
  2002年   1238篇
  2001年   960篇
  2000年   753篇
  1999年   346篇
  1998年   145篇
  1997年   111篇
  1996年   103篇
  1995年   91篇
  1994年   78篇
  1993年   69篇
  1992年   158篇
  1991年   156篇
  1990年   134篇
  1989年   106篇
  1988年   114篇
  1987年   135篇
  1986年   109篇
  1985年   106篇
  1984年   76篇
  1983年   82篇
  1982年   42篇
  1981年   37篇
  1980年   29篇
  1979年   51篇
  1978年   64篇
  1977年   28篇
  1976年   29篇
  1974年   29篇
  1973年   31篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
Acute myeloid leukemia (AML) is a disease of the elderly population and survival remains poor after failure of hypomethylating agents (HMA). The BCL‐2 inhibitor venetoclax demonstrated activity as monotherapy and in combination with chemotherapy or HMA in AML. In this case series, patients with secondary AML (sAML) not eligible for intensive chemotherapy and refractory to HMA were treated with venetoclax within a named patient program at our tertiary cancer center in Salzburg, Austria. Between April 2017 and September 2018, seven patients with sAML received venetoclax therapy. Two out of seven patients achieved a complete remission upon venetoclax initiation with a PFS of 505 days and 352 days and another patient achieved complete peripheral blood blast clearing within nine days after start of venetoclax. Among the venetoclax responders, primary refractory disease to prior HMA therapy was documented, 2 patients harbored IDH1/IDH2 mutations and one patient had an antecedent myeloproliferative neoplasm. High BCL‐2 and/or BIM expression in myeloblasts was found in venetoclax responders and response was significantly associated with overall survival (responders: 364 days versus non‐responders: 24 days, P = 0.018). Venetoclax monotherapy is safe and is able to induce durable responses in elderly patients with secondary AML after treatment failure with HMA.  相似文献   
53.
54.
55.
Currently, adoptive immunotherapy is considered as one of the leading treatments in cancer. Successful adoptive immunotherapy depends on producing large numbers of desired T cells ex vivo for infusion. This requires an effective protocol for maximum functional T‐cell expansion while keeping the time and costs to a minimum. Current T‐cell expansion protocols are diverse in their methodology, and a universal protocol of expansion is wanting. Also, new findings regarding T‐cell biology, signaling, and activation have reshaped the strategies of T‐cell propagation over the years, introducing new ways to expand T cells. Here, we reviewed different conditions for blood‐derived polyclonal T‐cell expansion so as to elucidate the influential factors of T‐cell expansion and their efficacy.  相似文献   
56.
Several studies have used a variety of neuroimaging techniques to measure brain activity during the voiding phase of micturition. However, there is a lack of consensus on which regions of the brain are activated during voiding. The aim of this meta‐analysis is to identify the brain regions that are consistently activated during voiding in healthy adults across different studies. We searched the literature for neuroimaging studies that reported brain co‐ordinates that were activated during voiding. We excluded studies that reported co‐ordinates only for bladder filling, during pelvic floor contraction only, and studies that focused on abnormal bladder states such as the neurogenic bladder. We used the activation‐likelihood estimation (ALE) approach to create a statistical map of the brain and identify the brain co‐ordinates that were activated across different studies. We identified nine studies that reported brain activation during the task of voiding in 91 healthy subjects. Together, these studies reported 117 foci for ALE analysis. Our ALE map yielded six clusters of activation in the pons, cerebellum, insula, anterior cingulate cortex (ACC), thalamus, and the inferior frontal gyrus. Regions of the brain involved in executive control (frontal cortex), interoception (ACC, insula), motor control (cerebellum, thalamus), and brainstem (pons) are involved in micturition. This analysis provides insight into the supraspinal control of voiding in healthy adults and provides a framework to understand dysfunctional voiding. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc.  相似文献   
57.
There are various modifications of the transverse rectus abdominis musculocutaneous flap and deep inferior epigastric perforator flap to reduce the morbidity of the donor site or to augment the vascularity of the flap. For microanastomosis of multiple pedicles, multiple recipient vessels or an intervening vein graft should be provided. In addition, alternative perforator‐based flaps used in breast reconstruction have small caliber pedicles. Therefore, small recipient vessels such as internal thoracic artery perforators are more suitable for appropriate microanastomosis. Therefore, it is important to acquaint the distribution and anatomical characteristics of internal thoracic artery perforators. We researched the perforators running in the intercostal spaces under the pectoralis major muscle to provide an overview of the anatomical distribution and characteristics of the perforators in patients who underwent immediate subpectoral implant‐based breast reconstructions. In our study, the major perforators (diameter > 1.5 mm) were easily found 2–7 cm medially between the third and fourth intercostal space and were sparse in the lateral area from the midline of the breast (usually 8–9 cm lateral to the midsternal line) and above the third rib. In each side of the breast, the average number of perforators greater than 1.5 mm was 1.6, and the average number of perforators between 1 mm and 1.5 mm in diameter was 3.2. Our results provide information about perforators in the anterior chest wall related to the breast area. Clin. Anat. 32:471–475, 2019. © 2018 Wiley Periodicals, Inc.  相似文献   
58.
Ulcerative colitis (UC) is a chronic recurrent inflammation of the colon. It has been proposed that the UC pathogenesis may be related to vitamin D deficiency and/or vitamin D administration in UC patients may have an ameliorating effect on the intestinal inflammation. The aim of this study was to assess the effect of vitamin D on the serum levels of immune cytokines in UC patients. In this double‐blind randomized controlled trial, 90 mild‐to‐moderate UC patients were assigned to get either a single muscular injection of 7.5 mg vitamin D3 or 1 mL normal saline as placebo. Three months later serum levels of IL‐4, IL‐10, IL‐12p70, IFN‐γ, and TNF‐α were measured. Two group variables were compared using independent t‐test and analysis of covariance (ANCOVA). There was a significant increase in vitamin D only in the vitamin D group. Compared to placebo, vitamin D had significant decreasing effects on serum TNF‐α, IFN‐γ, and IL12p70 levels, but it had no significant effect on serum levels of IL4 and IL10. Vitamin D seems to inhibit Th1 immune responses and have no effect on Th2 responses. The findings of this study support several in vitro studies, which suggest a therapeutic immunomodulatory potential of vitamin D.  相似文献   
59.
Brucellosis is a worldwide bacterial zoonosis caused by Brucella spp. No approved vaccine is available for human use against the disease. In this study, outer membrane vesicles (OMVs) from a Brucella melitensis biovar 1 human isolate obtained in Iran were used to immunize BALB/c mice (n = 12) by 2 intramuscular injections with a 2‐week interval. Another group of 12 mice was used as non‐vaccinated controls. Two weeks after the last vaccination, six mice of each group were sacrificed, and proliferation and interferon gamma (IFNγ) production responses of their splenocytes were evaluated following in vitro stimulation with killed Brucella cells. The other mice were challenged with the virulent B. melitensis isolate. Two weeks later, mice were killed and spleens were cultured to determine the number of the challenge strain. The results showed proliferative response and IFNγ production of splenocytes from vaccinated mice (stimulation index: 2.18 ± 0.57, and 1519.35 ± 10.70 pg/mL, respectively) were significantly higher than those of control mice (stimulation index: 1.02 ± 0.02, and 210.01 ± 17.58 pg/mL, respectively). Numbers of the challenge strain in spleens of vaccinated mice were also significantly less than those in the controls with 1.6 units of protection. Our study revealed vaccination with OMVs of the B. melitensis isolate could induce specific immune responses and protection against infection in the mouse model suggesting their potential application for active immunization against brucellosis.  相似文献   
60.
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