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   1018篇
  免费   54篇
  国内免费   7篇
耳鼻咽喉   2篇
儿科学   38篇
妇产科学   5篇
基础医学   156篇
口腔科学   69篇
临床医学   122篇
内科学   211篇
皮肤病学   17篇
神经病学   75篇
特种医学   96篇
外科学   85篇
综合类   20篇
一般理论   1篇
预防医学   47篇
眼科学   19篇
药学   55篇
中国医学   12篇
肿瘤学   49篇
  2024年   1篇
  2023年   12篇
  2022年   28篇
  2021年   71篇
  2020年   41篇
  2019年   57篇
  2018年   52篇
  2017年   41篇
  2016年   57篇
  2015年   47篇
  2014年   62篇
  2013年   79篇
  2012年   103篇
  2011年   99篇
  2010年   58篇
  2009年   28篇
  2008年   57篇
  2007年   67篇
  2006年   41篇
  2005年   26篇
  2004年   22篇
  2003年   15篇
  2002年   6篇
  1999年   1篇
  1998年   2篇
  1997年   1篇
  1996年   1篇
  1995年   3篇
  1991年   1篇
排序方式: 共有1079条查询结果,搜索用时 15 毫秒
1.
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   
2.
OBJECTIVES: To develop an immune-competent animal model for mucosally derived squamous cell carcinoma (SCCA). STUDY DESIGN: Fifteen Fischer 344 rats were inoculated with 1, 2, 5, 10, or 20 x 10(6) FAT7 cells in their flanks. The animals were observed for tumor growth and metastasis. RESULTS: All animals developed tumors that grew exponentially. Pulmonary metastases developed in all animals and 13% developed lymph node metastases. CONCLUSION: The FAT7 flank tumor in Fischer 344 rats is a new animal model that closely resembles the behavior of human mucosal head and neck cancer. SIGNIFICANCE: The existence of an immune-competent, mucosally derived, and reliable animal model of SCCA that somewhat resembles human head and neck SCCA gives the opportunity to perform immune-modulating experiments on head and neck cancer in these animals. EBM rating: B-3.  相似文献   
3.
Lasers in Medical Science - Treatment of cutaneous leishmaniasis (CL) continues to be a health concern, and alternative therapies with fewer side effects are substantially needed. This study aimed...  相似文献   
4.
Pseudoangiomatous stromal hyperplasia (PASH) is a rare benign breast entity scarcely reported in the medical literature. Its pathogenesis, etiology, and optimal treatment are still unknown. PASH tumors have a broad spectrum of clinical presentations and might be mistaken for malignancies. The authors present six patients diagnosed with PASH.  相似文献   
5.
Carbon nanotubes (CNTs) as electrically conductive materials are of great importance in the fabrication of flexible electronic devices and wearable sensors. In this regard, the evaporation-driven self-assembly of CNTs has attracted increasing attention. CNT-based applications are mostly concerned with the alignment of CNTs and the density of CNT films. In the present work, we focus on the latter by trying to achieve an optimal evaporation-driven deposition with the densest CNT ring. Although surfactants are used for effective dispersion and colloidal stabilization of CNTs in the aqueous phase, their excessive usage induces Marangoni eddies in the evaporating sessile droplets, leading to poor ring depositions. Thus, there is an optimum surfactant concentration that contributes to CNTs deagglomeration and results in the densest ring-like deposition with relatively high thickness. We report that this optimum concentration for sodium dodecyl sulfate (SDS) as a surfactant can be approximately considered as much as the concentration of multi-walled carbon nanotubes (MWCNTs) as the colloidal nanoparticles. Optimal depositions show the lowest electrical resistances for each CNT concentration, making them suitable for electronic applications. We also propose the multiple depositions method in which a new droplet is printed after the complete evaporation of the previous droplet. This method can lead to denser rings with a higher conductivity using lower concentrations of CNTs. Lastly, we fabricate strain sensors based on the optimal evaporation-driven deposition of CNTs which show higher gauge factors than the commercial strain gauges, corroborating the applicability of our method.

Our discovery reveals the existence of an optimum SDS/CNT concentration ratio to achieve the highest conductivity of ring deposition for strain sensing.  相似文献   
6.
Ermin is an actin‐binding protein found almost exclusively in the central nervous system (CNS) as a component of myelin sheaths. Although Ermin has been predicted to play a role in the formation and stability of myelin sheaths, this has not been directly examined in vivo. Here, we show that Ermin is essential for myelin sheath integrity and normal saltatory conduction. Loss of Ermin in mice caused de‐compacted and fragmented myelin sheaths and led to slower conduction along with progressive neurological deficits. RNA sequencing of the corpus callosum, the largest white matter structure in the CNS, pointed to inflammatory activation in aged Ermin‐deficient mice, which was corroborated by increased levels of microgliosis and astrogliosis. The inflammatory milieu and myelin abnormalities were further associated with increased susceptibility to immune‐mediated demyelination insult in Ermin knockout mice. Supporting a possible role of Ermin deficiency in inflammatory white matter disorders, a rare inactivating mutation in the ERMN gene was identified in multiple sclerosis patients. Our findings demonstrate a critical role for Ermin in maintaining myelin integrity. Given its near‐exclusive expression in myelinating oligodendrocytes, Ermin deficiency represents a compelling “inside‐out” model of inflammatory dysmyelination and may offer a new paradigm for the development of myelin stability‐targeted therapies.  相似文献   
7.
8.
IntroductionWe aimed to compare perioperative and postoperative outcomes and to assess the safety and feasibility of same-day trial of void (TOV) in patients who underwent standard holmium laser enucleation of the prostate (HoLEP) vs. MOSESTM HoLEP (MoLEP).MethodsWe conducted a retrospective review of prospectively collected data of patients that underwent HoLEP (100 W) or MoLEP (120 W) with same-day catheter removal three hours postoperatively at our institution from August 2018 to September 2021. Patient demographics, intraoperative parameters, and postoperative outcomes were analyzed. Data were compared as means with standard deviation and medians with interquartile range (IQR) or numbers and percentages. Continuous and categorical variables were assessed using the Mann-Whitney U test and Chi-squared test, respectively. Predictors of shorter enucleation time and failed same-day TOV were investigated.ResultsOf the 90 patients included, 28 underwent HoLEP while 62 had MoLEP. There was no significant difference between the groups in terms of the successful TOV (23 [82%] vs. 58 [93.5%], p=0.1) and readmission rate (3 [10.7%] vs. 1 [1.6%], p=0.08); however, the MoLEP group had a significantly shorter mean enucleation time (p<0.001), mean hemostasis time (p<0.001), mean morcellation time (p=0.003), and lower mean energy used (p<0.001). On the logistic regression model, MoLEP (odds ratio [OR] 0.03, 95% confidence interval [CI] 0.007–0.19, p<0.001), lower preoperative prostate-specific antigen (PSA) test (OR 1.25, 95% CI 1.01–1.55, p=0.03), and smaller prostate size (OR 1.06, 95% CI 1.02–1.09, p<0.001) were independent predictors of shorter enucleation time. History of preoperative retention was the only significant factor associated with a failed same-day TOV (p=0.04). There was no difference in intraoperative or postoperative complication rates or postoperative functional outcomes between the two technologies.ConclusionsSame-day TOV and discharge are feasible following standard HoLEP and MoLEP, with comparable outcomes; however, the use of MOSESTM technology offered better enucleation efficiency with excellent hemostatic potential. Preoperative retention was the only predictor of failed same-day TOV.  相似文献   
9.
10.
ObjectiveWe conducted a systematic review and dose–response meta-analysis of prospective studies to summarize findings on the associations between intakes of soy, soy isoflavones, and soy protein and risk of mortality from all causes, cancers, and cardiovascular diseases.MethodsOnline databases were systematically searched to identify relevant articles published earlier than May 2018. We applied restricted cubic splines using random-effects analysis to assess dose–response associations. Between-study heterogeneity was assessed by I2 value and Cochrane Q test. Potential publication bias was assessed by visual inspection of funnel plots and Begg regression test.ResultsIn total, 23 prospective studies with an overall sample size of 330,826 participants were included in the current systematic review and the meta-analysis. Soy/soy products consumption was inversely associated with deaths from cancers (pooled relative risk 0.88, 95% CI 0.79 to 0.99; P=0.03; I2=47.1%, 95% CI 0.0% to 75.4%) and cardiovascular diseases (pooled effect size: 0.85, 95% CI 0.72 to 0.99; P=0.04; I2=50.0%, 95% CI 0.0% to 77.6%). Such significant associations were also observed for all-cause mortality in some subgroups of the included studies, particularly those with higher quality. In addition, higher intake of soy was associated with decreased risk of mortality from gastric, colorectal, and lung cancers as well as ischemic cardiovascular diseases. Participants in the highest category of dietary soy isoflavones intake had a 10% lower risk of all-cause mortality compared with those in the lowest category. We also found that a 10-mg/day increase in intake of soy isoflavones was associated with 7% and 9% decreased risk of mortality from all cancers and also breast cancer respectively. Furthermore, a 12% reduction in breast cancer death was indicated for each 5-g/day increase in consumption of soy protein. However, intake of soy protein was not significantly associated with all-cause and cardiovascular diseases mortality.ConclusionsSoy and its isoflavones may favorably influence risk of mortality. In addition, soy protein intake was associated with a decreased risk in the mortality of breast cancer. Our findings may support the current recommendations to increase intake of soy for greater longevity.  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