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   1826篇
  免费   126篇
  国内免费   9篇
耳鼻咽喉   25篇
儿科学   35篇
妇产科学   42篇
基础医学   235篇
口腔科学   85篇
临床医学   174篇
内科学   354篇
皮肤病学   51篇
神经病学   144篇
特种医学   44篇
外科学   214篇
综合类   26篇
一般理论   1篇
预防医学   127篇
眼科学   145篇
药学   155篇
中国医学   15篇
肿瘤学   89篇
  2023年   19篇
  2022年   59篇
  2021年   74篇
  2020年   55篇
  2019年   75篇
  2018年   72篇
  2017年   52篇
  2016年   67篇
  2015年   79篇
  2014年   88篇
  2013年   111篇
  2012年   138篇
  2011年   189篇
  2010年   80篇
  2009年   65篇
  2008年   111篇
  2007年   119篇
  2006年   82篇
  2005年   83篇
  2004年   69篇
  2003年   64篇
  2002年   52篇
  2001年   10篇
  2000年   10篇
  1999年   11篇
  1998年   4篇
  1997年   6篇
  1996年   7篇
  1995年   6篇
  1994年   7篇
  1993年   8篇
  1992年   10篇
  1991年   14篇
  1990年   3篇
  1989年   3篇
  1988年   4篇
  1986年   4篇
  1984年   8篇
  1983年   3篇
  1982年   5篇
  1980年   3篇
  1979年   2篇
  1978年   2篇
  1974年   4篇
  1973年   3篇
  1972年   4篇
  1971年   3篇
  1970年   2篇
  1967年   1篇
  1965年   3篇
排序方式: 共有1961条查询结果,搜索用时 15 毫秒
1.
The coronavirus disease 2019 (COVID-19) has currently caused the mortality of millions of people around the world. Aside from the direct mortality from the COVID-19, the indirect effects of the pandemic have also led to an increase in the mortality rate of other non-COVID patients. Evidence indicates that novel COVID-19 pandemic has caused an inflation in acute cardiovascular mortality, which did not relate to COVID-19 infection. It has in fact increased the risk of death in cardiovascular disease (CVD) patients. For this purpose, it is dramatically inevitable to monitor CVD patients’ vital signs and to detect abnormal events before the occurrence of any critical conditions resulted in death. Internet of things (IoT) and health monitoring sensors have improved the medical care systems by enabling latency-sensitive surveillance and computing of large amounts of patients’ data. The major challenge being faced currently in this problem is its limited scalability and late detection of cardiovascular events in IoT-based computing environments. To this end, this paper proposes a novel framework to early detection of cardiovascular events based on a deep learning architecture in IoT environments. Experimental results showed that the proposed method was able to detect cardiovascular events with better performance (95.30% average sensitivity and 95.94% mean prediction values).  相似文献   
2.
Diabetes, as a low‐grade chronic inflammatory disease, causes disruption in proper function of immune and metabolic system. Chromium is an important element required for normal lipid and glucose metabolism. Chromium deficiency is correlated with elevation in cardiometabolic risk, which results from increased inflammation. This systematic review was conducted to discover the potential roles of chromium on inflammatory biomarkers. Eligible studies were all in vitro, animal and human studies published in English‐language journals from inception until October 2018. PubMed, Scopus, Embase, ProQuest and Google Scholar databases were searched to fined interventional studies from the effects of chromium on inflammatory biomarkers such as tumour necrosis factor a (TNF‐a), C‐reactive protein (CRP), interleukins, monocyte chemoattractant protein–1 (MCP‐1), intercellular adhesion molecule‐1 (ICAM‐1) and adipocytokines in hyperglycaemia and diabetes. Out of 647 articles found in the search, only 14 articles were eligible for analysis, three in vitro studies, eight animal studies and three human studies. Twelve of the 14 studies included in this review, chromium significantly decreased inflammatory factors. The findings of this review indicate, based on in vitro and in vivo studies, that chromium might have potential anti‐inflammatory properties, but some of the studies did not show anti‐inflammatory effects for chromium (two studies). There are only three studies in humans with controversial results. Therefore, more consistent randomized double‐blind controlled trials are needed to reach relevant clinical recommendations, as well as to determine the precise mechanism, of chromium on inflammation in diabetes.  相似文献   
3.
4.
5.
6.
7.
A 57-year-old woman with cutaneous mastocytosis of 23 years duration developed a hyperpigmented abdominal plaque composed of confluent indurated papules that enlarged for a period of 1 year to 12 x 8 cm. Biopsy showed dermal infiltration by closely packed spindle-shaped mast cells, fibroblasts, collagen, and scattered lymphocytes, predominantly T-suppressor cells. Electron microscopy showed close contact between mast cells, fibroblasts, and lymphocytes. Piecemeal mast cell degranulation and extrusion of mast cell granules was seen, with rare mast cell granules in fibroblasts, and collagen fibers in peripheral and perinuclear endoplasmic reticulum of mast cells. the term Fibrous mastocytoma is suggested for this tumor-like dermal fibrosis, possibly induced by lymphokines.  相似文献   
8.
We investigated the ability of two overlapping fragments of staphylococcal enterotoxin B (SEB), which encompass the whole toxin, to induce protection and also examined if passive transfer of chicken anti-SEB antibodies raised against the holotoxin could protect rhesus monkeys against aerosolized SEB. Although both fragments of SEB were highly immunogenic, the fragments failed to protect mice whether they were injected separately or injected together. Passive transfer of antibody generated in chickens (immunoglobulin Y [IgY]) against the whole toxin suppressed cytokine responses and was protective in mice. All rhesus monkeys treated with the IgY specific for SEB up to 4 h after challenge survived lethal SEB aerosol exposure. These findings suggest that large fragments of SEB may not be ideal for productive vaccination, but passive transfer of SEB-specific antibodies protects nonhuman primates against lethal aerosol challenge. Thus, antibodies raised in chickens against the holotoxin may have potential therapeutic value within a therapeutic window of opportunity after SEB encounter.  相似文献   
9.
Odds ratio was used to evaluate relationship between sepsis in cattle less than 1 year old and mastitis in cows and erythrocyte glutathione peroxides (GSH-PX) activity as an indicator of selenium status. Data were from 178 blood samples collected from referred cases to Urmia University, Veterinary Teaching Hospital. Low activity of GSH-PX was significantly associated with higher odds of developing sepsis (P=0.005) in young cattle and mastitis (P=0.044) in adult cows. The odds ratios for the low activity of GSH-PX on incidence of sepsis and mastitis were 4.74 and 3.95, respectively. Selenium deficiency was associated with sepsis in young cattle and mastitis in cows, i.e., cattle with low activity of erythrocyte GSH-PX were at increased risk of sepsis and mastitis.  相似文献   
10.
Staphylococcal enterotoxins (SEs) belong to a large group of bacterial exotoxins that cause severe immunopathologies, especially when delivered as an aerosol. SEs elicit the release of lethal amounts of cytokines by binding to major histocompatibility complex (MHC) class II and cross-linking susceptible T-cell receptors. Efforts to develop effective therapeutic strategies to protect against SEs delivered as an aerosol have been hampered by the lack of small animal models that consistently emulate human responses to these toxins. Here, we report that human leukocyte antigen-DQ8 (HLA-DQ8) transgenic (Tg) mice, but not littermate controls, succumbed to lethal shock induced by SEB aerosols without potentiation. Substantial amounts of perivascular edema and inflammatory infiltrates were noted in the lungs of Tg mice, similar to the pathology observed in nonhuman primates exposed by aerosol to SEB. Furthermore, the observed pathologies and lethal shock correlated with an upsurge in proinflammatory cytokine mRNA gene expression in the lungs and spleens, as well as with marked increases in the levels of proinflammatory circulating cytokines in the Tg mice. Unlike the case for littermate controls, telemetric evaluation showed significant hypothermia in Tg mice exposed to lethal doses of SEB. Taken together, these results show that this murine model will allow for the examination of therapeutics and vaccines developed specifically against SEB aerosol exposure and possibly other bacterial superantigens in the context of human MHC class II receptors.  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