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   3623篇
  免费   166篇
  国内免费   67篇
耳鼻咽喉   76篇
儿科学   58篇
妇产科学   155篇
基础医学   611篇
口腔科学   77篇
临床医学   294篇
内科学   602篇
皮肤病学   96篇
神经病学   226篇
特种医学   120篇
外科学   614篇
综合类   82篇
预防医学   154篇
眼科学   59篇
药学   365篇
中国医学   32篇
肿瘤学   235篇
  2023年   29篇
  2022年   48篇
  2021年   92篇
  2020年   55篇
  2019年   68篇
  2018年   91篇
  2017年   84篇
  2016年   98篇
  2015年   144篇
  2014年   163篇
  2013年   168篇
  2012年   259篇
  2011年   261篇
  2010年   154篇
  2009年   113篇
  2008年   187篇
  2007年   202篇
  2006年   193篇
  2005年   167篇
  2004年   140篇
  2003年   119篇
  2002年   111篇
  2001年   101篇
  2000年   92篇
  1999年   85篇
  1998年   27篇
  1997年   21篇
  1996年   28篇
  1995年   21篇
  1994年   19篇
  1993年   12篇
  1992年   34篇
  1991年   40篇
  1990年   38篇
  1989年   34篇
  1988年   19篇
  1987年   22篇
  1986年   22篇
  1985年   30篇
  1984年   19篇
  1983年   13篇
  1979年   16篇
  1978年   21篇
  1977年   13篇
  1976年   13篇
  1975年   15篇
  1974年   17篇
  1973年   14篇
  1972年   18篇
  1966年   16篇
排序方式: 共有3856条查询结果,搜索用时 15 毫秒
101.
The role of different parameters (including genetic factors) on the timing and extend of left ventricle hypertrophy in patients with aortic stenosis is not defined. In our study we analyze the influence of clinical, echocardiographic parameters and I/D polymorphism of the angiotensin converting enzyme gene on the left ventricle hypertrophy (left ventricle mass index) in this group of patients. The study was done with the group of 302 pts with aortic stenosis--120 women and 182 men; mean age 58 +/- 11 yrs. Stepwise (backward) regression was used to assess the influence of the analyzed parameters (age, gender, history of hypertension, EF, MGA, presence of significant coronary artery disease and I/D ACE polymorphism) on the LVH in the all pts and in the women and the men separately. In the whole group the LVMI depends on EF (t = -6.5; p = 0.0001--higher LVMI in lower EF), MGA (t = 3.9; p = 0.0001--higher LVMI in higher MGA) and gender (t = 2.8; p = 0.005--higher LVMI in men). In women LVMI was related with EF (t = -3.6; p = 0.001--higher LVMI in lower EF), age (t = 2.9; p = 0.004--higher LVMI in older pts) and MGA (t = 2.5; p = 0.013--higher LVMI in higher MGA). In men the LVMI depends on EF (t = -4.8; p = 0.0001--higher LVMI in lower EF) and MGA (t = 1.98; p = 0.049--higher LVMI in higher MGA). Significant relationship between LVMI and results of I/D ACE polymorphism was observed both in women and men. I/D polymorphism relationship with LVMI was divergent in these 2 groups--association of higher LVMI with lack of DD type of polymorphism in women and presence of DD polymorphism in men. CONCLUSIONS: 1. Left ventricle hypertrophy in pts aortic stenosis is higher in men than in women. 2. In women left ventricle hypertrophy is related with ejection fraction, maximal aortic gradient, age and I/D ACE polymorphism; in men it is related to EF, MGA and I/D ACE polymorphism. 3. The influence of I/D ACE polymorphism on the left ventricle hypertrophy is divergent in women and men--in women related to the lack of DD polymorphism, in men related to the presence of DD polymorphism.  相似文献   
102.
Stec S  Makowska E  Kułakowski P 《Kardiologia polska》2005,62(4):376-80; discussion 380
Clinical usefulness of implantable loop recorder in diagnosis of unexplained syncope - case report. A case of a 67-year-old female with recurrent syncope is presented. In spite of extensive investigation, the cause of syncope remained unknown. The patient received insertable loop recorder (ILR). One month after implantation the patient suffered two syncopal episodes. ECG recorded by ILR showed asystolic pause of 8 seconds at the time of conversion of atrial fibrillation to sinus rhythm. This was the first ILR implantation in Poland which was covered by public health insurance and not by private funds.  相似文献   
103.
Abstract In this work, patients having type 2 diabetes mellitus and diabetic mothers were tested for the presence of mitochondrial DNA point mutation A3243G. This mutation is associated with the MELAS syndrome (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes), diabetes and deafness. Twenty-two diabetic persons were screened. DNA was isolated from peripheral blood lymphocytes and from swabs of oral mucosa. The mitochondrial DNA point mutation A3243G was detected using PCR-RFLP test. The mutation was detected in oral mucosal DNA of two patients (but not from lymphocyte DNA). One patient was a man with hearing and visual impairments and proteinuria; the other was a woman having proteinuria but no hearing impairment. The mutation was not detectable in oral mucosal DNA from the control persons: 20 diabetic patients having diabetic fathers and 22 healthy, nondiabetic volunteers. The incidence of mitochondrial DNA point mutation A3243G in this study of Croatian diabetic patients is in line with data in the literature.  相似文献   
104.

Aims

We compared upper trunk anthropometric indices with overall and central obesity indicators to predict the presence of type 2 diabetes in middle-aged and elderly Korean individuals.

Methods

This cross-sectional investigation included 4079 rural and urban participants aged 40–80 years. Neck, thoracic, waist (WC), and hip circumferences were measured by a reliable and standardized method. The neck-to-hip ratio, the thoracic-to-hip ratio (THR), and the waist-to-hip ratio (WHR) were calculated. A 75-g oral glucose tolerance test was performed. Type 2 diabetes was defined based on the guidelines of the World Health Organization (1999).

Results

The receiver operator characteristic curve analysis indicated that THR and WHR were better than body mass index (BMI) and other anthropometric indices at predicting the presence of type 2 diabetes. The adjusted odds ratios (OR) across quartiles of THR were slightly higher than the ORs for WHR, particularly in the highest quartile (odds ratios and 95% CI: 2.11 (1.47–3.04) versus 1.95 (1.37–2.77) in men; 3.40 (2.18–5.31) versus 2.31 (1.48–3.60) in women). The associations of THR and WHR with type 2 diabetes remained significant, despite a slight attenuation after a multivariate adjustment for BMI. The joint effect of BMI and THR on the risk of type 2 diabetes was larger than that of BMI and WHR.

Conclusions

THR may be a novel marker of type 2 diabetes, particularly in women, and its association with diabetes was independent of BMI and WHR.  相似文献   
105.
Inhalation of fine particulate matter (PM2.5) is associated with elevated pulmonary injury attributed to the loss of vascular barrier integrity. Black ginseng (BG), steamed 9 times and dried ginseng, and its major protopanaxatriol type ginsenosides (ginsenoside Rg4, Rg6, Rh4, Rh1, and Rg2) exhibited various biological activities including anti-septic, anti-diabetic, wound healing, immune-stimulatory, and anti-antioxidant activity. The aim of this study was to investigate the beneficial effects of Rgx365 (a protopanaxatriol type rare ginsenosides fraction) on PM-induced lung endothelial cell (EC) barrier disruption and pulmonary inflammation. Permeability, leukocyte migration, activation of proinflammatory proteins, generation of reactive oxygen species (ROS), and histology were examined in PM2.5-treated EC and mice. Rgx365 significantly scavenged PM2.5-induced ROS, inhibited ROS-induced activation of p38 mitogen-activated protein kinase (MAPK), activated Akt in purified pulmonary EC, which helped maintain endothelial integrity. Further, Rgx365 reduced vascular protein leakage, leukocyte infiltration, and proinflammatory cytokine release in bronchoalveolar lavage fluids in PM-induced mouse lung tissues. Data suggested that Rgx365 might exhibit protective effects in PM-induced inflammatory lung injury and vascular hyperpermeability.  相似文献   
106.
107.

Purpose

The purpose of the study is to determine corticospinal organization using intraoperative neurophysiologic monitoring (IONM) during resective epilepsy surgery for patients with congenital hemiparesis and intractable epilepsy.

Methods

Ten patients, aged 3–17, with intractable epilepsy underwent resective surgery. Transcranial stimulation (TCS) was achieved using a pair of cork screws at Cz and C3/C4, respectively. A 1?×?4 stimulating electrode strip was placed on the presumed motor cortex of the affected hemisphere for direct cortical stimulation (DCS) after craniotomy. Multipulse TCS and DCS train stimulation was delivered, with simultaneous recordings from bilateral abductor pollicis brevis and abductor halluces, to determine the corticospinal projection pattern of the paretic limbs.

Results

The above mapping techniques revealed ipsilateral corticospinal projections from the contralesional hemisphere to target muscles in the paretic limbs in three patients, projections from both hemispheres to target muscles in three, and preserved crossed projections from the affected hemisphere in four. Nine patients were seizure free after surgery. Five had unchanged postoperative functional status, and three showed minimally improved use of the paretic hand. Two developed new motor deficits after surgery, which may have been due to a premotor syndrome in one patient, since it completely resolved within 2 weeks. The other experienced increased weakness of the paretic lower limb because a small part of the eloquent cortex was removed for better seizure control.

Conclusions

Using IONM to define the corticospinal projection pattern is a valuable technique that can potentially replace preoperative fMRI and transcranial magnetic stimulation in resective epilepsy surgery, particularly for younger patients.  相似文献   
108.
HLA class I molecules play a role both in viral infection control and in autoimmune diseases development. rs9264942T > C polymorphism in HLA-C gene was found to impact on HLA-C surface expression level and to be associated with HIV-1 control. It was found that these HLA alleles which protect against AIDS are associated with autoimmune disease e.g. psoriasis vulgaris (PsV). Whether rs9264942 SNP is associated with PsV was investigated here. rs9264942T > C was genotyped in 292 PsV patients, and 254 controls using TaqMan Genotyping Assay.  相似文献   
109.
Exendin-4 (EX4) has been reported to attenuate myocardial ischemia and reperfusion (I/R) injury and inflammatory and oxidative responses. Nuclear DNA-binding protein high-mobility group box 1 (HMGB1) protein acts as a late mediator of severe vascular inflammatory conditions. However, the effect of EX4 on HMGB1-induced inflammatory response has not been studied. First, we accessed this question by monitoring the effects of posttreatment EX4 on lipopolysaccharide (LPS) and cecal ligation and puncture (CLP)-mediated release of HMGB1 and HMGB1-mediated regulation of proinflammatory responses in human umbilical vein endothelial cells (HUVECs) and septic mice. Posttreatment EX4 was found to suppress LPS-mediated release of HMGB1 and inhibited HMGB1-mediated hyperpermeability and leukocyte migration in septic mice. EX4 also induced downregulation of CLP-induced release of HMGB1, production of IL-6, and mortality. Collectively, these results suggest that EX4 may be regarded as a candidate therapeutic agent for treatment of vascular inflammatory diseases via inhibition of the HMGB1 signaling pathway.  相似文献   
110.
Various attempts have been made to find treatments for Duchenne muscular dystrophy (DMD) patients. Exon skipping is one of the promising technologies for DMD treatment by restoring dystropin protein, which is one of the muscle components. It is well known that losartan, an angiotensin II type1 receptor blocker, promotes muscle regeneration and differentiation by lowering the level of transforming growth factor–beta1 signaling. In this study, we illustrated the combined effects of exon skipping and losartan on skeletal muscle of mdx mice. We supplied mdx mice with losartan for 2 weeks before exon skipping treatment. The losartan with the exon skipping group showed less expression of myf5 than the losartan treated group. Also the losartan with exon skipping group recovered normal muscle architecture, in contrast to the losartan group which still showed many central nuclei. However, the exon skipping efficiency and the restoration of dystrophin protein were lower in the losartan with exon skipping group compared to the exon skipping group. We reveal that losartan promotes muscle regeneration and shortens the time taken to restore normal muscle structure when combined with exon skipping. However, combined treatment of exon skipping and losartan decreases the restoration of dystrophin protein meaning decrease of exon skipping efficiency.  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