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   3652篇
  免费   133篇
  国内免费   138篇
耳鼻咽喉   38篇
儿科学   62篇
妇产科学   70篇
基础医学   257篇
口腔科学   96篇
临床医学   468篇
内科学   884篇
皮肤病学   45篇
神经病学   352篇
特种医学   169篇
外科学   526篇
综合类   281篇
一般理论   1篇
预防医学   128篇
眼科学   31篇
药学   179篇
中国医学   68篇
肿瘤学   268篇
  2024年   29篇
  2023年   52篇
  2022年   88篇
  2021年   59篇
  2020年   26篇
  2019年   80篇
  2018年   92篇
  2017年   33篇
  2016年   77篇
  2015年   85篇
  2014年   59篇
  2013年   76篇
  2012年   2312篇
  2011年   694篇
  2010年   16篇
  2009年   15篇
  2008年   5篇
  2007年   8篇
  2006年   15篇
  2005年   13篇
  2004年   4篇
  2003年   6篇
  2002年   2篇
  2001年   9篇
  2000年   13篇
  1999年   8篇
  1998年   3篇
  1997年   1篇
  1996年   6篇
  1995年   3篇
  1994年   4篇
  1993年   9篇
  1992年   1篇
  1991年   4篇
  1989年   2篇
  1988年   3篇
  1987年   3篇
  1986年   3篇
  1984年   1篇
  1980年   1篇
  1979年   1篇
  1965年   1篇
  1963年   1篇
排序方式: 共有3923条查询结果,搜索用时 15 毫秒
51.
ObjectiveTo analyze the impact of reperfusion by either primary percutaneous coronary intervention (PPCI) or fibrinolysis, and mortality rates of a pre-hospital fast-track network for treating patients with ST-elevation myocardial infarction (STEMI).Methods and ResultsA pre-hospital network for STEMI patients, designated the Green Lane for Acute Myocardial Infarction (GL-AMI), has been implemented in the southern region of Portugal – the Algarve Project. We performed an observational study based on a prospective registry of 1338 patients admitted to Faro Hospital between 2004 and 2009, classified in two groups according to the method of admission: emergency department group (EDG) and GL-AMI group (GLG). More patients from GLG were reperfused (p < 0.0001). PPCI was the preferred method of reperfusion, 73.1% in GLG and 45.3% in EDG. Time delays were significantly shorter in GLG, except for pre-hospital delay: pre-hospital delay (p = 0.11); door-to-needle (p < 0.0001); door-to-balloon (p < 0.0001); and delay between symptoms and reperfusion (p < 0.0001). In-hospital mortality (4.3% vs 9.2%, p = 0.0007) and 6-month mortality (6.3% vs 13.8%, p < 0.0001) were significantly lower in GLG.ConclusionsThe Algarve Project significantly reduced the time delay between onset of symptoms and reperfusion, significantly increased the rate of reperfusion, and significantly reduced in-hospital and six-month mortality.  相似文献   
52.
53.
54.
55.
The molecular mechanisms underlying development of obesity and diabetic complications are not well understood. Drosophila has become a popular model organism for studying a variety of human diseases. We discuss here emerging Drosophila models of obesity and diabetic complications.  相似文献   
56.
We are reporting a case of 68-year-old woman with insulinoma, after a non-successful tumor surgery and a long-term diazoxide treatment. She had a lot of hypoglycemia cases, and a weight gain of 50?kg. An abdominal CT scan demonstrated a tumor 28?mm in the diameter, in the head of the pancreas. The patient did not agree for the repeated insulinoma surgery. Furthermore, we found a lesion in the left adrenal gland (14?mm in the diameter) and in the right lung (8?mm in the diameter). Pheochromocytoma was diagnosed on the basis of hypertension, elevated levels of normetanephrine in the 24-h urine collection, and an elevated level of norepinephrine in a plasma sample. After the left adrenal gland removal we observed lower blood pressure. Since we had revealed the presence of somatostatin receptors by the somatostatin receptors scintigraphy, we decided to control hypoglycemia by a monthly subcutaneous administration of the long-acting lanreotide. Because of higher glucose levels (300-400?mg/dl) we started an intense insulin therapy. Nowadays, the patient feels better, she has lost 20?kg of her body weight, and we have observed normal blood glucose levels during the long-term lanreotide treatment. We have noticed neither side effects nor hypoglycemic episodes and we have reduced the dose of insulin. The presented case can be an evidence of the effective treatment of the pancreatic neuroendocrine tumor of insulinoma type, with somatostatin analogue.  相似文献   
57.
Although Ren-2 transgenic rat (TGR) is defined as a model of angiotensin II-dependent hypertension, we studied whether the renin-angiotensin system (RAS) is really the main contributor to blood pressure (BP) elevation in hetero- and homozygous TGRs. Moreover, we examined whether repeated antisense (AS) therapy against AT(1) receptors would have a similar effect on the BP and the contribution of the principle vasoconstrictor/vasodilator systems to BP regulation in young and adult TGRs. From the age of 30 (young) and 100 (adult) days, rats were injected with AS for 40 days in 10-day intervals. After 10 and 40 days of AS therapy, the basal BP and acute BP responses to the sequential blockade of the RAS, sympathetic nervous (SNS) and nitric oxide systems were determined in conscious rats. The RAS system was the major system maintaining elevated BP in young homozygous animals, whereas there was an increasing contribution of the SNS in heterozygous TGR with age. The AS therapy in the young TGR had a transient BP-lowering effect that was associated with reduced cardiac hypertrophy; the AS therapy was most effective in young homozygous TGR, causing a substantial reduction of angiotensin-dependent vasoconstriction. In heterozygous rats, AS therapy at earlier stages was related to an inhibition of sympathetic vasoconstriction, whereas to RAS inhibition in established hypertension. In conclusion, repeated AS therapy had transient antihypertensive effects exclusively in young TGR. The contribution of the RAS to BP maintenance is highly important only in homozygous TGRs, whereas it is surpassed by SNS in heterozygous TGR.  相似文献   
58.
Mean platelet volume (MPV) has been recognized as an independent risk factor of hypertension. Hypertensive end-organ damage worsens the prognosis in hypertensive patients. We aimed to investigate the relationship between MPV levels and subclinical end-organ damage in hypertensive patients. One hundred and sixteen hypertensive patients (81 women, 35 men, with a mean age of 53 ± 11) were included in the study. There was no correlation between MPV and left-ventricular mass index (LVMI) (r = 0.145; P = 0.14) or albuminuria (r = 0.009; P = 0.93). Among the individuals that had grade I and grade II retinopathy, MPV levels (8.3 ± 2 fL, 8.2 ± 1.3 fL; P = 0.28) were similar either. We concluded that there was no correlation between MPV and markers of end-organ damage in hypertensive patients.  相似文献   
59.
Circulating active tissue factor (TF) and activated factor XI (FXIa) have been detected in subgroups of acute coronary syndromes (ACSs) and stable angina patients. We sought to evaluate the determinants of active TF and FXIa in stable angina patients. We studied 124 consecutive stable angina patients. Recent ACS, atrial fibrillation, and anticoagulant therapy were the exclusion criteria. Plasma active TF and FXIa were determined by measuring the response to inhibitory antibodies. T helper 1 lymphocyte (Th1) and Th2 responses were assessed in plasma by interleukin (IL)-4, IL-6, IL-8, IL-10, IL-18, interferon-γ, and tumor necrosis factor-α, oxidative stress by 8-isoprostaglandin F(2α) (8-iso-PGF(2α)), and coagulation by prothrombin fragments F1+2 (F1+2) and free TF pathway inhibitor (f-TFPI). TF and FXIa activity were detected in 25 (20.2%) and 49 (39.5%) stable angina patients, respectively. Both factors were found in 23 (18.5%) patients. Patients with detectable TF or FXIa had higher F1+2, 8-iso-PGF(2α), IL-6, but not other cytokines, and lower f-TFPI (all P < 0.001) compared with the remainder. There were no intergroup differences with regard to cardiovascular risk factors or medication. Multivariate analysis showed that F1+2 and f-TFPI were the only independent predictors of the TF presence, whereas 8-iso-PGF(2α) and F1+2 predicted the presence of FXIa in stable angina patients. In stable angina patients, circulating active TF and FXIa are associated with enhanced thrombin formation, with a minor effect of inflammatory mediators. Moreover, FXIa is also related to oxidative stress, indicating additional links between coagulation and free radical generation in stable angina.  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