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   384篇
  免费   15篇
  国内免费   1篇
耳鼻咽喉   4篇
儿科学   18篇
妇产科学   8篇
基础医学   80篇
口腔科学   17篇
临床医学   27篇
内科学   65篇
皮肤病学   2篇
神经病学   74篇
特种医学   7篇
外科学   21篇
预防医学   38篇
眼科学   3篇
药学   15篇
中国医学   1篇
肿瘤学   20篇
  2023年   2篇
  2022年   3篇
  2021年   15篇
  2020年   14篇
  2019年   13篇
  2018年   10篇
  2017年   9篇
  2016年   7篇
  2015年   7篇
  2014年   16篇
  2013年   17篇
  2012年   28篇
  2011年   29篇
  2010年   18篇
  2009年   15篇
  2008年   23篇
  2007年   38篇
  2006年   23篇
  2005年   23篇
  2004年   24篇
  2003年   15篇
  2002年   11篇
  2001年   6篇
  1999年   2篇
  1997年   1篇
  1996年   1篇
  1994年   1篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1986年   1篇
  1985年   4篇
  1984年   1篇
  1983年   2篇
  1981年   1篇
  1979年   2篇
  1978年   1篇
  1971年   2篇
  1970年   2篇
  1969年   1篇
  1968年   2篇
  1967年   1篇
  1966年   1篇
排序方式: 共有400条查询结果,搜索用时 234 毫秒
21.
22.
23.
Background  It has been proposed that there is improvement in glucose and insulin metabolism after weight loss in patients who underwent diet restriction and bariatric surgery. Methods  Eleven normal glucose tolerant (NGT) morbidly obese patients [body mass index (BMI), 46.1 ± 2.27 g/m2] and eight abnormal glucose metabolism (AGM) obese patients (BMI, 51.20 kg/m2) were submitted to diet-restriction and bariatric surgery. Prospective study on weight loss changes, over the glucose, insulin metabolism, glucagon-like peptide-1 (GLP-1), and adiponectin levels were evaluated by oral glucose tolerance test during three periods: T1 (first evaluation), T2 (pre-surgery), and T3 (9 months after surgery). Results  Insulin levels improved after surgery. T1 was 131.1 ± 17.60 pmol/l in the NGT group and 197.57 ± 57.94 pmol/l in the AGM group, and T3 was 72.48 ± 3.67 pmol/l in the NGT group and 61.2 ± 9.33 pmol/l in the AGM group. The major reduction was at the first hour of the glucose load as well as fasting levels. At 9 months after surgery (T3), GLP-1 levels at 30 and 60 min had significantly increased in both groups. It was observed that the AGM group had higher levels of GLP-1 at 30 min (34.06 ± 6.18 pmol/l) when compared to the NGT group (22.69 ± 4.04 pmol/l). Homeostasis model assessment of insulin resistance from the NGT and AGM groups had a significant reduction at periods T3 in relation to T1 and T2. Adiponectin levels had increased concentration in both groups before and after surgical weight loss. However, it did not have any statistical difference between periods T1 vs. T2. Conclusions  Weight loss by surgery leads to improvement in the metabolism of carbohydrates in relation to sensitivity to the insulin, contributing to the reduction of type 2 diabetes incidence. This improvement also was expressed by the improvement of the levels of adiponectin and GLP-1.  相似文献   
24.
Three novel alpha-globin variants were found during a screening program for hemoglobinopathies in blood donors at the UNICAMP Hematology and Hemotherapy Center, Campinas, State of S?o Paulo, Southeastern Brazil. They were named for the town of origin of the carrier as Hb Itapira [alpha30(B11)Glu-->Val], Hb Bom Jesus da Lapa [alpha30(B11)Glu-->Ala] and Hb Boa Esperan?a [alpha16(A14)Lys-->Thr]. Hb Itapira, like Hb Bom Jesus da Lapa, shows an electrophoretic mobility similar to that of Hb S [beta6(A3)GluVal, GAG-->GTG] at alkaline pH; it is associated with a triplicate alpha-globin allele (alphaalphaalpha(anti 3.7)) and corresponds to only 5.5% of the total hemoglobin (Hb). Hb Boa Esperan?a, found in two different individuals, moves faster than Hb A and exhibits an abnormal functional performance.  相似文献   
25.
Purpose:   Studies suggest that higher cognitive functions could precipitate seizures in juvenile myoclonic epilepsy (JME). The present study aimed to analyze the effects of higher mental activity on epileptiform discharges and seizures in patients with JME and compare them to those of habitual methods of activation.
Methods:   Seventy-six patients with JME (41 female) underwent a video-EEG (electroencephalography) neuropsychologic protocol (VNPP) and habitual methods of activation for 4–6 h.
Results:   Twenty-nine of the 76 (38.2%) presented provocative effect, and inhibition was seen in 28 of 31 (90.3%). A mixed effect was observed in 11 (35.5%), and 30 patients (39.5%) suffered no effect of VNPP. Action-programming tasks were more effective than thinking in provoking epileptiform discharges (23.7% and 11.0% of patients, respectively, p = 0.03). Inhibitory effect was observed equally in the various categories of tasks, except in mental calculation, which had a higher inhibitory rate. Habitual methods of activation were more effective than VNPP in provoking discharges. Anxiety disorders were diagnosed in 24 of 58 patients (41.4%); anxious patients had greater discharge indexes and no significant inhibitory effect on VNPP.
Discussion:   Praxis exerted the most remarkable provocative effect, in accordance with the motor circuitry hyperexcitability hypothesis in JME. Inhibitory effect, which had no such task specificity, might be mediated by a widespread cortical–thalamic pathway, possibly involving the parietal cortex. The frequent inhibitory effect found under cortical activation conditions, influenced by the presence of anxiety, supports nonpharmacologic therapeutic interventions in JME.  相似文献   
26.
Purpose: To investigate the cerebral metabolic differences between patients with juvenile myoclonic epilepsy (JME) and normal controls and to evaluate to what extent these metabolic alterations reflect involvement of an epileptic network. Methods: Sixty patients with JME were submitted to multi‐voxel proton spectroscopy (1H‐MRS) at 1.5 T over medial prefrontal cortex (MPC), primary motor cortex (PMC), thalamus, striatum, posterior cingulate gyrus (PCG), and insular, parietal, and occipital cortices. We determined ratios for integral values of N‐acetyl‐aspartate (NAA) and glutamate‐glutamine (GLX) over creatine‐phosphocreatine (Cr). The control group (CTL) consisted of 30 age‐ and sex‐matched healthy volunteers. Results: The NAA/Cr ratio, a measure of neuronal injury, was reduced in PMC, MPC, and thalamus among patients. In addition, they had an altered GLX/Cr ratio, which is involved in excitatory activity, on PMC, MPC, and PCG, where it was reduced, whereas it was increased on insula and striatum. Multiple regression analysis revealed the strongest correlation between thalamus and MPC, but the thalamus was also correlated with insula, occipital cortex, and striatum among patients. Lower NAA/Cr was observed with advancing age and duration of epilepsy, regardless of frequency of seizures and antiepileptic drug therapy in thalamus and frontal cortex. Discussion: The identification of a specific network of neurochemical dysfunction in patients with JME, with diverse involvement of particular structures within the thalamocortical circuitry, suggests that cortical hyperexcitability in JME is not necessarily diffuse, supporting the knowledge that the focal/generalized distinction of epileptogenesis should be reconsidered. Furthermore, evidence is provided toward progressive neuronal dysfunction in JME.  相似文献   
27.
28.
29.
30.
Considering the importance of people participating in the construction of new health models, this study aimed to characterize and analyze contributions brought by community to health actions carried out in a Family Health Unit. It is a documentary analysis based on the records of 24 monthly meetings between the team and community. After reading the records, subject was divided into four themes: material and human resources, availability to secondary level health services, community adherence to the unit activities, health promotion and disease prevention. Discussions opened a wide perspective on health and stimulated co-responsibility, stronger links and information exchanging. Nevertheless, there is a need to improve community effective participation in the co-management of the health system.  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