全文获取类型
收费全文 | 2330833篇 |
免费 | 174951篇 |
国内免费 | 3275篇 |
专业分类
耳鼻咽喉 | 32082篇 |
儿科学 | 75676篇 |
妇产科学 | 62673篇 |
基础医学 | 345335篇 |
口腔科学 | 63566篇 |
临床医学 | 209750篇 |
内科学 | 452430篇 |
皮肤病学 | 51704篇 |
神经病学 | 183827篇 |
特种医学 | 87941篇 |
外国民族医学 | 490篇 |
外科学 | 352906篇 |
综合类 | 47297篇 |
现状与发展 | 12篇 |
一般理论 | 848篇 |
预防医学 | 181223篇 |
眼科学 | 54135篇 |
药学 | 174503篇 |
9篇 | |
中国医学 | 4408篇 |
肿瘤学 | 128244篇 |
出版年
2019年 | 19561篇 |
2018年 | 27072篇 |
2017年 | 20371篇 |
2016年 | 22765篇 |
2015年 | 25656篇 |
2014年 | 36135篇 |
2013年 | 53996篇 |
2012年 | 74722篇 |
2011年 | 79456篇 |
2010年 | 47089篇 |
2009年 | 44600篇 |
2008年 | 74657篇 |
2007年 | 79512篇 |
2006年 | 80330篇 |
2005年 | 77814篇 |
2004年 | 74378篇 |
2003年 | 71548篇 |
2002年 | 69208篇 |
2001年 | 108550篇 |
2000年 | 111151篇 |
1999年 | 92867篇 |
1998年 | 25361篇 |
1997年 | 21979篇 |
1996年 | 22360篇 |
1995年 | 22563篇 |
1994年 | 20771篇 |
1993年 | 19596篇 |
1992年 | 71888篇 |
1991年 | 70063篇 |
1990年 | 68364篇 |
1989年 | 65643篇 |
1988年 | 60254篇 |
1987年 | 59093篇 |
1986年 | 55200篇 |
1985年 | 52973篇 |
1984年 | 39245篇 |
1983年 | 33306篇 |
1982年 | 19767篇 |
1981年 | 17776篇 |
1979年 | 35795篇 |
1978年 | 25584篇 |
1977年 | 21136篇 |
1976年 | 20270篇 |
1975年 | 21767篇 |
1974年 | 26099篇 |
1973年 | 24770篇 |
1972年 | 23190篇 |
1971年 | 22018篇 |
1970年 | 20226篇 |
1969年 | 19287篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Zyuz’kov G. N. Zhdanov V. V. Miroshnichenko L. A. Polyakova T. Yu. Stavrova L. A. Simanina E. V. Minakova M. Yu. Agafonov V. I. Churin A. A. 《Bulletin of experimental biology and medicine》2022,173(5):615-619
Bulletin of Experimental Biology and Medicine - The psychopharmacological effects of a stimulator of functions of progenitor cells of the nervous tissue STAT3 inhibitor (STAT3 Inhibitor XIV, LLL12)... 相似文献
22.
23.
24.
25.
Ahmad Adebayo Irekeola Engku Nur Syafirah E.A.R. Yusuf Wada Rohimah Mohamud Norhafiza Mat Lazim Chan Yean Yean Rafidah Hanim Shueb 《Indian journal of medical microbiology》2022,40(3):420-426
BackgroundEpstein-Barr virus (EBV) is a member of the herpesvirus family that is known to ubiquitously infect people worldwide. However, the actual prevalence of EBV infection in diseased patients in Nigeria, remains unknown. This study was thus conducted to ascertain the true prevalence.MethodsA systematic review and meta-analysis of published data was conducted according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Electronic databases including PubMed, Scopus, ScienceDirect, and Google Scholar were searched for studies reporting the occurrence of EBV infection among patients with established diseases. Studies were included if they assessed EBV infection in diseased patients in Nigeria. Data were extracted and subsequently analysed using R software. Funnel plot and Egger's regression test was used to assess publication bias, while JBI prevalence tool was used to assess study quality.ResultsA total of 13 studies covering 228 cases of EBV infection among 1157 diseased patients were included. Summary estimates were computed using random-effects model. The pooled prevalence of EBV infection was 20.3% (95% CI: 10.8–34.9, I2 ?= ?92.26, p ?< ?0.001). When stratified according to the type of disease, higher estimates were obtained for patients suffering from Kaposi's sarcoma (98.7%, 95% CI: 82.2–99.9) and Nasopharyngeal malignancy (85.7%, 95% CI: 70.0–93.9). A prevalence of 13.4% (95% CI: 6.0–27.4) and 12.2% (95% CI: 4.8–27.8) was derived for the most reported patient populations, lymphoma and HIV, respectively.ConclusionThis first meta-analysis on the prevalence of EBV among Nigerian patients suffering from various diseases reveals a prevalence that emphasises the need to routinely monitor EBV infection in all EBV-associated diseases in Nigeria. 相似文献
26.
Peter A. Bretscher 《Scandinavian journal of immunology》2022,95(1):e13110
The widely accepted Cytokine Milieu Hypothesis proposes that the cytokine milieu, in which antigen activates CD4 T cells, from a non-T cell source, primarily determines the Th subset to which the ensuing effector Th cells belong. We focus on the generation of Th1 and Th2 cells. We briefly restate the grounds for the Threshold Hypothesis we favour for how the Th1/Th2 phenotype of a response is primarily determined: tentative and robust thresholds of antigen-mediated CD4 T cell interactions lead to the generation of Th1 and Th2 cells. The component antigens of pathogens are present in different amounts. It is expected, within the context of the threshold mechanism that, although there is often an initial predominance of Th1 or Th2 cells, some Th cells of the opposing type are initially generated. An initially somewhat heterogeneous Th response is known to become with time more ‘coherent’ in its Th1/Th2 phenotype. I propose The Cytokine Implementation Hypothesis as a mechanism for how coherence is achieved. Most cytokines made by Th cells of one subset tend to facilitate the further generation of Th cells of this subset and/or inhibit the generation of Th cells of opposing subsets, accounting for how coherence may be achieved. Many observations on which The Cytokine Milieu Hypothesis is based are accounted for by this alternative hypothesis. We outline predictions of the new hypothesis and discuss the importance of coherence of immune responses for their efficacy in protecting against foreign invaders. 相似文献
27.
Cynthia S. E. Hendrikse MD Phyllis van der Ploeg MD PhD Nienke M. A. van de Kruis MD Jody H. C. Wilting MD Floor Oosterkamp BSc Pauline M. M. Theelen MSc Christianne A. R. Lok MD PhD Joanne A. de Hullu MD PhD Huberdina P. M. Smedts MD PhD M. Caroline Vos MD PhD Brenda M. Pijlman MD Loes F. S. Kooreman MD Johan Bulten MD PhD Marjolein H. F. M. Lentjes-Beer MD PhD Steven L. Bosch MD PhD Anja van de Stolpe MD PhD Sandrina Lambrechts MD PhD Ruud L. M. Bekkers MD PhD Jurgen M. J. Piek MD PhD 《Cancer》2023,129(9):1361-1371
Background
Advanced low-grade ovarian carcinoma (LGOC) is difficult to treat. In several studies, high estrogen receptor (ER) protein expression was observed in patients with LGOC, which suggests that antihormonal therapy (AHT) is a treatment option. However, only a subgroup of patients respond to AHT, and this response cannot be adequately predicted by currently used immunohistochemistry (IHC). A possible explanation is that IHC only takes the ligand, but not the activity, of the whole signal transduction pathway (STP) into account. Therefore, in this study, the authors assessed whether functional STP activity can be an alternative tool to predict response to AHT in LGOC.Methods
Tumor tissue samples were obtained from patients with primary or recurrent LGOC who subsequently received AHT. Histoscores of ER and progesterone receptor (PR) were determined. In addition, STP activity of the ER STP and of six other STPs known to play a role in ovarian cancer was assessed and compared with the STP activity of healthy postmenopausal fallopian tube epithelium.Results
Patients who had normal ER STP activity had a progression-free survival (PFS) of 16.1 months. This was significantly shorter in patients who had low and very high ER STP activity, with a median PFS of 6.0 and 2.1 months, respectively (p < .001). Unlike ER histoscores, PR histoscores were strongly correlated to the ER STP activity and thus to PFS.Conclusions
Aberrant low and very high functional ER STP activity and low PR histoscores in patients with LGOC indicate decreased response to AHT. ER IHC is not representative of functional ER STP activity and is not related to PFS. 相似文献28.
Biomedical Engineering - The possible use of the vortex effect in medical transfusion–infusion solution heaters was studied. A design for a device is presented, along with the trial results.... 相似文献
29.
Laura A. Huppert MD Ozge Gumusay MD Dame Idossa MD Hope S. Rugo MD 《CA: a cancer journal for clinicians》2023,73(5):480-515
Hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer is defined by the presence of the estrogen receptor and/or the progesterone receptor and the absence of HER2 gene amplification. HR-positive/HER2-negative breast cancer accounts for 65%–70% of all breast cancers, and incidence increases with increasing age. Treatment varies by stage, and endocrine therapy is the mainstay of treatment in both early stage and late-stage disease. Combinations with cyclin-dependent kinase 4/6 inhibitors have reduced distant recurrence in the early stage setting and improved overall survival in the metastatic setting. Chemotherapy is used based on stage and tumor biology in the early stage setting and after endocrine resistance for advanced disease. New therapies, including novel endocrine agents and antibody-drug conjugates, are now changing the treatment landscape. With the availability of new treatment options, it is important to define the optimal sequence of treatment to maximize clinical benefit while minimizing toxicity. In this review, the authors first discuss the pathologic and molecular features of HR-positive/HER2-negative breast cancer and mechanisms of endocrine resistance. Then, they discuss current and emerging therapies for both early stage and metastatic HR-positive/HER2-negative breast cancer, including treatment algorithms based on current data. 相似文献
30.
A. M. Crawford 《Anaesthesia》2023,78(11):1323-1326