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   2715篇
  免费   194篇
  国内免费   11篇
耳鼻咽喉   27篇
儿科学   110篇
妇产科学   52篇
基础医学   376篇
口腔科学   29篇
临床医学   181篇
内科学   649篇
皮肤病学   83篇
神经病学   157篇
特种医学   72篇
外科学   257篇
综合类   217篇
预防医学   337篇
眼科学   36篇
药学   196篇
中国医学   12篇
肿瘤学   129篇
  2023年   31篇
  2022年   58篇
  2021年   84篇
  2020年   45篇
  2019年   62篇
  2018年   65篇
  2017年   49篇
  2016年   67篇
  2015年   90篇
  2014年   109篇
  2013年   142篇
  2012年   181篇
  2011年   164篇
  2010年   102篇
  2009年   63篇
  2008年   137篇
  2007年   118篇
  2006年   117篇
  2005年   110篇
  2004年   96篇
  2003年   97篇
  2002年   101篇
  2001年   74篇
  2000年   78篇
  1999年   68篇
  1998年   21篇
  1997年   29篇
  1996年   23篇
  1995年   19篇
  1994年   16篇
  1993年   17篇
  1992年   39篇
  1991年   37篇
  1990年   28篇
  1989年   27篇
  1988年   26篇
  1987年   18篇
  1986年   27篇
  1985年   23篇
  1984年   19篇
  1979年   15篇
  1976年   14篇
  1975年   12篇
  1974年   18篇
  1973年   31篇
  1972年   11篇
  1970年   12篇
  1969年   11篇
  1968年   11篇
  1967年   11篇
排序方式: 共有2920条查询结果,搜索用时 0 毫秒
51.
Burden and risk factors for wasting in the first 6 months of life among Indian children are not well documented. We used data from India's National Family Health Survey 4 to estimate the prevalence of severe wasting (weight for length < ‐3 SD) among 18,898 infants under 6 months of age. We also examined the association of severe wasting with household, maternal, and child‐related factors using multivariable logistic regression analysis. Prevalence of severe wasting among infants less than 6 months of age was 14.8%, ranging from 3.5 to 21% across states. Low birth weight (<2,500 g; adjusted odds ratio [AOR] 1.40, 95% CI [1.19, 1.65]), nonutilization of supplementary nutrition by mother during lactation (AOR 1.23, 95% CI [1.05, 1.43]), and anthropometric assessment during summer (AOR 1.37, 95% CI [1.13, 1.65]) and monsoon months (AOR 1.53, 95% CI [1.20, 1.95]) were associated with higher odds of severe wasting. Infants aged 2 to 3 months (AOR 0.78, 95% CI [0.66, 0.93]) and 4 to 5 months (AOR 0.65, 95% CI [0.55, 0.73]) had lower odds of severe wasting as compared with the 0‐ to 1‐month category. This analysis reveals a high burden of severe wasting in infants less than 6 months in India. Preventive interventions must be targeted at reducing low birth weight due to fatal growth restriction and prematurity. Appropriate care practices at facilities and postdischarge with extra attention to those born small and sick can prevent further deterioration in nutritional status.  相似文献   
52.
Swimming Induced Pulmonary Edema, or SIPE, is an emerging condition occurring in otherwise healthy individuals during surface swimming or diving that is characterized by cough, dyspnea, hemoptysis, and hypoxemia. It is typically found in those who spend time in cold water exercise with heavy swimming and surface swimming, such as civilian training for iron Man, triathalon, and military training. We report the case of a highly trained young female swimmer in excellent cardiopulmonary health, who developed acute alveolar pulmonary oedema in an open water swimming training diagnosed in the emergency department using POCUS ultrasound.  相似文献   
53.
54.
Single-walled carbon nanotubes synthesized with iron (Fe-SWCNT) or gadolinium (Gd-SWCNT) show promise as high performance multimodal contrast and drug-delivery agents. Our purpose was to evaluate potential vasoactive effects of SWCNT. Stable aqueous solutions of Fe-SWCNTs or Gd-SWCNTs were made using the biocompatible amphiphilic polymer N-(carbonyl-methoxypolyethyleneglycol 2000)-1,2-distearoylsn-glycero-3- phosphoethanolamine (PEG-DSPE). Both aggregated and non-aggregated (sonicated) formulations were tested. The initial vasoactivity of the formulations and their potential for inducing pro-inflammatory endothelial dysfunction were investigated in the hamster cheek pouch and murine cremaster muscle intravital microscopy models. These models provide an assay to test several formulations/dosages in a paired fashion. Abluminal exposure to small arterioles exposes both endothelial and vascular smooth muscle cells. Using abluminal exposures of dosages that would approximate the first pass of an i.v. bolus injection, both Fe-SWCNTs and Gd-SWCNTs were immediately vasoactive. Aggregated formulations induced dilation and non-aggregated formulations induced constriction in both hamsters and mice. Endothelial dysfunction was evident after exposure to either aggregated or non-aggregated forms. General loss of dilator capability was seen after exposure to non-aggregated but not aggregated forms. Thus concentrations mimicking bolus dosing of PEG-DSPE coated SWCNT induce both acute and chronic vascular responses.  相似文献   
55.
Development of left ventricular pseudoaneurysm is a rare complication of mitral valve surgery and requires urgent surgical intervention. We describe a case of pseudoaneurysm of membranous septum following repeat mitral valve replacement with the use of multimodality imaging.  相似文献   
56.
Takayasu’s arteritis (TA) is a granulomatous large vessel vasculitis more commonly seen in India. The vascular inflammation in TA results in stenoses of affected vessels. Usually this is a slow process with good collateral circulation; only rarely does critical limb ischemia result. We present two patients of TA who presented with gangrene of extremities, and review eight prior such patients reported in the literature. With appropriate diagnosis and treatment with oral corticosteroids and low-dose aspirin, none of our patients had recurrence at a mean follow-up of 3.8 ± 2.8 years. Although rare, TA can present with gangrene and rheumatologists need to be aware of this unusual but limb-threatening manifestation of TA to institute appropriate therapy in a timely manner.  相似文献   
57.
The ubiquitous gram-positive bacterium Staphylococcus aureus occupies a unique niche in humans for its ability to survive both as a commensal and a life-threatening pathogen. Its complex relationship with the host and its ability to engender a throng of virulence factors, have hindered the development of a successful vaccine against it. The use of immunoadjuvants to enhance host immunity and prevent the shift from commensalism to pathogenicity is a rational approach for containing infection. The objective of this study was to understand the mechanisms by which alum and two phytol-derived immunoadjuvants, phytanol (PHIS-01) 1 and phytanyl chloride (PCl) 2 shape the interaction between S. aureus and its murine host. We studied the effects of the phytol derivatives, relative to alum, on the induction of inflammatory cytokines and chemokines, recruitment of CD11b+ cells, generation of specific anti-S. aureus antibodies and in vitro clearance of S. aureus. Our results showed that both PHIS-01 and PCl were stronger inducers of protective cytokines IL-17 and IL-1β than alum, and far exceeded alum in enhancing anti-S. aureus antibody response. However, both alum and the phytol derivatives (particularly PCl) promoted efficient recruitment of CD11b+ cells. Furthermore, PHIS-01, alum and to a lesser extent, PCl were able to up-regulate the expression of key inflammation-related genes that were highly down-regulated by S. aureus alone. In vitro killing assays showed that both PHIS-01 and PCl were far more potent than alum in promoting S. aureus clearance; this indicated their efficiency in shaping an effective anti-S. aureus immune microenvironment. In summary, our study provides evidence for the better effectiveness of phytol-derived immunoadjuvants over alum in enhancing anti-S. aureus immunity.  相似文献   
58.
Diabetic nephropathy remains the principal cause of end‐stage renal failure in the UK and its prevalence is set to increase. People with diabetes and end‐stage renal failure on maintenance haemodialysis are highly vulnerable, with complex comorbidities, and are at high risk of adverse cardiovascular outcomes, the leading cause of mortality in this population. The management of people with diabetes receiving maintenance haemodialysis is shared between diabetes and renal specialist teams and the primary care team, with input from additional healthcare professionals providing foot care, dietary support and other aspects of multidisciplinary care. In this setting, one specialty may assume that key aspects of care are being provided elsewhere, which can lead to important components of care being overlooked. People with diabetes and end‐stage renal failure require improved delivery of care to overcome organizational difficulties and barriers to communication between healthcare teams. No comprehensive guidance on the management of this population has previously been produced. These national guidelines, the first in this area, bring together in one document the disparate needs of people with diabetes on maintenance haemodialysis. The guidelines are based on the best available evidence, or on expert opinion where there is no clear evidence to inform practice. We aim to provide clear advice to clinicians caring for this vulnerable population and to encourage and improve education for clinicians and people with diabetes to promote empowerment and self‐management.  相似文献   
59.
To perform sputum analysis for verification of pulmonary changes in premenopausal rural Indian women chronically exposed to biomass smoke during cooking.Three consecutive morning sputum samples were collected from 196 women (median age 34 years) cooking with biomass and 149 age-matched control women cooking with cleaner fuel liquefied petroleum gas. Smears made on slides were stained with Papanicolaou and Perl's Prussian blue. Airway oxidative stress was estimated as reactive oxygen species (ROS) generation (by flow cytometry) and superoxide dismutase (SOD) level (by spectrophotometry) in sputum cells. Airway inflammation was measured as sputum levels of interleukin (IL)-6, -8 and tumor necrosis factor- alpha (TNF-α). Particulate matter of diameter less than 10 (PM10) was measured using laser photometer while benzene exposure was monitored by measuring trans, trans-muconic acid (t,t-MA) in urine by HPLC-UV. Compared with control, sputum of biomass users contained more neutrophils, lymphocytes, eosinophils, alveolar macrophages, and showed presence of ciliocytophthoria, Charcot-Leyden crystals, Curschmann's spiral. ROS generation was increased by 2-fold while SOD was depleted by 31% in biomass users. They also had higher sputum levels of IL-6, -8 and TNF-α. Levels of PM10 and t,t-MA were 2.9- and 5.8-times higher in biomass-using women. PM10 and t,t-MA levels were positively associated with cellular changes in the sputum, markers of airway inflammation, and oxidative stress. Cooking with biomass alters sputum cytology, and increases airway inflammation and oxidative stress that might result in further amplification of the tissue damaging cascade in women chronically exposed to biomass smoke.  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