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   6683篇
  免费   383篇
  国内免费   36篇
耳鼻咽喉   41篇
儿科学   267篇
妇产科学   153篇
基础医学   857篇
口腔科学   602篇
临床医学   525篇
内科学   1475篇
皮肤病学   184篇
神经病学   594篇
特种医学   557篇
外科学   637篇
综合类   69篇
预防医学   542篇
眼科学   53篇
药学   308篇
中国医学   40篇
肿瘤学   198篇
  2023年   43篇
  2022年   102篇
  2021年   167篇
  2020年   119篇
  2019年   191篇
  2018年   210篇
  2017年   157篇
  2016年   163篇
  2015年   192篇
  2014年   233篇
  2013年   324篇
  2012年   457篇
  2011年   463篇
  2010年   296篇
  2009年   232篇
  2008年   372篇
  2007年   360篇
  2006年   290篇
  2005年   255篇
  2004年   163篇
  2003年   171篇
  2002年   168篇
  2001年   116篇
  2000年   115篇
  1999年   84篇
  1998年   154篇
  1997年   135篇
  1996年   134篇
  1995年   103篇
  1994年   88篇
  1993年   93篇
  1992年   56篇
  1991年   49篇
  1990年   37篇
  1989年   86篇
  1988年   76篇
  1987年   70篇
  1986年   67篇
  1985年   77篇
  1984年   41篇
  1983年   41篇
  1982年   43篇
  1981年   28篇
  1980年   38篇
  1979年   31篇
  1978年   22篇
  1977年   27篇
  1976年   33篇
  1975年   34篇
  1969年   15篇
排序方式: 共有7102条查询结果,搜索用时 0 毫秒
1.
We report on 3 patients with pseudoathetosis, which are involuntary, slow, writhing movements due to loss of proprioception.  相似文献   
2.
We report a case of a prepubertal girl with juvenile primary hypothyroidism presenting as ovarian cysts and precocious puberty. The 7-year-old female was referred to our clinic because of a pelvic/abdominal mass and vaginal bleeding. Besides these findings, on physical examination we noticed the thyroid gland globally increased and the presence of secondary sexual characteristics. Based upon the clinical profile and investigations, the patient was diagnosed with juvenile primary hypothyroidism due to autoimmune thyroiditis. The cysts and precocious puberty resolved spontaneously after the simple replacement of thyroid hormone. It is important to bear in mind hypothyroidism in cases of girls presenting ovarian cysts and precocious puberty in order to avoid unnecessary surgery on the ovaries.  相似文献   
3.
4.
5.
Background: One hundred eighty-one patients were submitted to laparoscopic common bile duct exploration. Methods: A transcystic approach was used in 147 patients, choledochotomy in 14, and both in 20. The indications to perform a choledochotomy included stones larger than 20 mm, stones proximal to the cystic duct entrance, and cases in which the transcystic duct approach proved impossible or unsuccessful. Results: The common bile duct was drained by a T-tube in four patients, by laparoscopic sphincterotomy in one, by laparoscopic choledochoduodenostomy in one, and by a 10 Fr endoprosthesis in 28. The stent placement was technically feasible in all patients but one. The biliary drainage was adequate. Mean hospital stay was 2.1 days. Complication was limited to one umbilical infection and one self-limited biliary leak. Conclusions: The procedure proved to be technically simple, safe, and efficient, and resulted in a low morbidity rate and short hospital stay. Received: 29 March 1996/Accepted: 12 June 1996  相似文献   
6.
The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months  相似文献   
7.
Asthma patients that depend on emergency department (ED) services are generally considered to have extremely poor disease control and prognosis. It is important to identify characteristics related to poor disease control and frequent visits to the ED to apply appropriate clinical management. This study comprised a cross-sectional survey of consecutive patients with asthma exacerbation (age ≥12 years) presenting at the adult ED of a large, tertiary care, university-affiliated hospital over a 2-month period. The frequent visitors (FV) were defined by ≥3 visits to the ED in the preceding year, and the occasional visitors (OV) by ≤2 visits. Eighty-six patients (61 females and 25 males) were included in the study (mean age 38 ± 18 years). Of these patients, 51.2% were FV and 48.8% were OV. Sixty-nine percent had annual income lower than A$3000 and 66.3% had ≤8 years of the formal education. Only 18.6% had used inhaled corticosteroids, 79.1% identified the asthma attack severity, 70.9% increased or initiated inhaled β-agonist, 20.9% increased or initiated steroid therapy, and 55.8% had an asthma action plan for attack. The number of hospital admissions in past year (OR 4.3, P = .02), use of home nebulizer (OR 3.6, P = .05) and the lack of a written asthma action plan (OR 3.3, P = .03) were independently associated with frequent visits to the ED. We conclude that a substantial proportion of the patients that visit the ED are FV. These patients are more likely to have hospital admission in the past year, to use a home nebulizer, and to lack a written asthma action plan. They should be considered the most important target for asthma education.  相似文献   
8.
1. The antagonistic actions of parafluorohexahydrosiladiphenidol (pFHHSiD) at muscarinic receptors has been studied in cardiac muscle, smooth muscle and cell culture preparations. In this paper, the classification scheme of Doods et al. (1987) is employed. This scheme is based upon differential affinities of muscarinic antagonists. pFHHSiD exhibited high pA2 values at M3 receptors mediating contractions of guinea-pig ileum and oesophageal muscularis mucosae (7.8 and 8.2 respectively) whereas low values were determined at M2 receptors mediating negative inotropic responses in guinea-pig atria (6.0). Intermediate pA2 values were determined at M1 receptors mediating contractions of the canine femoral and saphenous veins. 2. The pA2 values of pFHHSiD at receptors mediating endothelial-dependent relaxation of rat aortic rings, rabbit jugular vein and canine femoral artery (7.6-7.9) were similar to those determined on the ileum. However, the pA2 values of pFHHSiD at receptors mediating contractions of the guinea-pig trachea (7.1), which has been previously shown to possess M3 receptors, were different from those determined in the ileum. 3. The similarity in pA2 values of pFHHSiD between the M3 receptors in guinea-pig ileum and the receptors mediating endothelial-dependent relaxations provide further evidence for the role of M3 receptors in this vascular response. Taken together, pA2 values for pFHHSiD range from 7.1 to 8.2, depending upon the M3 preparation used. The selectivity of the compound therefore for the M3 versus the M2 muscarinic receptor ranged from 13 to 163 fold.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
  相似文献   
10.
Summary Levels of dopamine (DA), noradrenaline (NA) and 5-hydroxytryptamine (serotonin, 5-HT) and their metabolites, and the activities of tyrosine hydroxylase (TH), tryptophan hydroxylase (TPH) and monoamine oxidase A and B (MAO-A and MAO-B) have been determined in the rat posterior thalamus after enucleation during postnatal development. DA and 5-HT turnover rate have been measured as 3,4-dihydroxyphenylalanine (DOPA) and 5-hydroxytryptophan (5-HTP) accumulation rates after central decarboxylase inhibition by 3-hydroxybenzylhydrazine (NSD-1015). The major changes were an increase in noradrenergic and serotoninergic metabolism in enucleated animals compared with control animals. A decrease of the MAO-A to MAO-B ratio during postnatal development was found.Abbreviations DA dopamine - DOPAC 3,4-dihydroxyphenylacetic acid - HVA homovanillic acid - DOPA 3,4-dihydroxyphenylalanine - NA noradrenaline - MHPG 3-methoxy-4-hydroxyphenylgly-col - NMN normetanephrine - TRP tryptophan - 5-HTP 5-hydroxytryptophan - 5-HT serotonin - 5-HIAA 5-hydroxy-3-indolacetic acid - TH tyrosine hydroxylase - TPH tryptophan hydroxylase - MAO-A monoamine oxidase-A - MAO-B monoamine oxidase-B Recipients of fellowships from I.I.E. del FISS Reincorporación de doctores y tecnólogos del M.E.C., and Perfeccionamiento de doctores y tecnólogos del MEC, Spain  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