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   5027篇
  免费   365篇
  国内免费   25篇
耳鼻咽喉   45篇
儿科学   137篇
妇产科学   144篇
基础医学   558篇
口腔科学   114篇
临床医学   462篇
内科学   1382篇
皮肤病学   150篇
神经病学   314篇
特种医学   151篇
外科学   709篇
综合类   143篇
一般理论   2篇
预防医学   303篇
眼科学   96篇
药学   341篇
中国医学   27篇
肿瘤学   339篇
  2024年   8篇
  2023年   83篇
  2022年   179篇
  2021年   342篇
  2020年   225篇
  2019年   259篇
  2018年   311篇
  2017年   192篇
  2016年   171篇
  2015年   186篇
  2014年   258篇
  2013年   327篇
  2012年   455篇
  2011年   402篇
  2010年   236篇
  2009年   147篇
  2008年   239篇
  2007年   257篇
  2006年   261篇
  2005年   221篇
  2004年   197篇
  2003年   141篇
  2002年   143篇
  2001年   13篇
  2000年   16篇
  1999年   12篇
  1998年   9篇
  1997年   11篇
  1996年   14篇
  1995年   13篇
  1994年   15篇
  1993年   16篇
  1992年   6篇
  1991年   6篇
  1990年   5篇
  1989年   7篇
  1988年   3篇
  1986年   2篇
  1985年   3篇
  1984年   2篇
  1983年   2篇
  1981年   2篇
  1978年   2篇
  1977年   2篇
  1974年   3篇
  1970年   1篇
  1967年   2篇
  1945年   2篇
  1943年   1篇
  1923年   2篇
排序方式: 共有5417条查询结果,搜索用时 31 毫秒
1.
The rise in popularity of hyaluronic acid (HA) dermal filler injection has caused an exceptional increase in the number of cases of reported irreversible blindness. Here, we reported a case of ischemic optic neuropathy and ophthalmoplegia following subcutaneous HA filler injection with complete visual recovery. A 31-year-old Chinese woman presented with sudden onset of right monocular visual impairment associated with diplopia. Patient had received a hyaluronic acid-containing ?ller injection for nasal dorsum augmentation twelve hours prior to presentation. Visual acuity of the right eye was counting finger. A right relative afferent pupillary defect was demonstrated with ophthalmoplegia. Humphrey visual field test disclosed a right inferior altitudinal field defect with impairment of colour vision. Computed tomography of the orbit revealed mild enlargement of the right medial and inferior recti muscles. Our patient showed a tremendous improvement of vision after a subcutaneous hyaluronidase injection with complete visual recovery within 2 weeks.  相似文献   
2.
The use of multifunctional materials for water remediation is a modern approach where adsorption phenomena and heterogeneous photocatalysis can be applied for the removal of pollutants. Since the ideal remediation system should be able to remove both organic and inorganic pollutants, a crucial aspect to consider is the knowledge of operational parameters affecting the removal process, especially when heavy metal ions are present in concoction as in real systems. Given the proven efficiency of multifunctional TiO2/Alg/FeNPs magnetic beads for the removal of model organic pollutants, this study investigated the possibility to exploit such system also for the removal of mixed heavy metals (MHM), specifically Cr(III), Cu(II), and Pb(II) ions, under ultraviolet irradiation at a wavelength of 254 nm. After a preliminary screening on the optimal catalyst loading, operating parameters such as the initial concentration of metal ions, contact and irradiation time, and pH were investigated to optimize the removal of metal ions using response surface methodology (RSM) via Box–Behnken design. Starting from a MHM solution containing 44 ppm of each metal ion, the removal of Pb(II), Cr(III), and Cu(II) ions in the aqueous solution was nearly completed (>98.4%) for all three ions within 72 min of irradiation at almost neutral pH (pH = 6.8). The stability of TiO2/Alg/FeNPs was confirmed by retrieving and reusing the beads in three consecutive cycles of heavy metals removal without observing significant changes in catalyst efficiency.  相似文献   
3.
4.
5.
BACKGROUND: Risk stratification in Brugada syndrome (BS) is controversial, especially in asymptomatic individuals. OBJECTIVE: The aim of this study was to evaluate the significance of lead aVR in patients with BS. METHODS: Twenty-four patients with the electrocardiogram pattern of BS (24 male, mean age 32.1 +/- 13.6 years) and 24 healthy age- and gender-matched controls were studied. RESULTS: Thirteen patients were symptomatic. The R-wave amplitude or R/q ratio in lead aVR was significantly greater in patients experiencing a recurrence compared with those who did not. The aVR sign was defined as R wave >/= 0.3 mV or R/q >/= 0.75 in lead aVR. Most of the recurrences (78%) were in patients with present aVR sign; 84% of BS patients with present aVR sign had events during follow-up. In contrast, only 27% of BS patients with absent aVR sign had events during follow-up. CONCLUSION: Our study shows significant correlation between a prominent R wave in lead aVR (aVR sign) and risk for development of arrhythmic events in BS. In the presence of BS, prominent R wave in lead aVR may reflect more right ventricular conduction delay and subsequently more electrical heterogeneity, which in turn is responsible for a higher risk of arrhythmia.  相似文献   
6.
Purpose  Congenital clasped thumb is a deformity that is associated with heterogeneous congenital anomalies and it has been addressed in many congenital syndromes. The aim of this study was to diagnose and evaluate cases of clasped thumb as regards the associated congenital anomalies and syndromes, and evaluation of the results of treatment of such cases. Methods  A prospective study on 40 patients with 73 clasped thumbs was done. All the patients’ data regarding their personal, family, pregnancy and developmental histories were recorded. All the patients were exposed to thorough clinical and radiological examination and genetic assessment. The cases were classified using the Tsuyuguchi et al. (J Hand Surg [Am] 10:613–618, 1985) classification into three types. Conservative treatment was adopted in ten hands, and surgical treatment was performed for 28 hands in 17 patients, with an average follow-up of 26 months. Results  Positive consanguinity was recorded in 57.5% of cases. Associated anomalies were recorded in 77.5% of cases. Type I was the most common one, followed by type III and then type II. Conservative treatment is effective in type I cases when presented early, and all patients were satisfied with the results of surgical treatment. Conclusions  We reported associated anomalies which are to our knowledge have not mentioned before in the literature which include; congenital blindness, radial deviation of the index finger and ventricular septal defect. We found that 68% of the patients had associated syndromes, and this has not been mentioned before. In this study, we found that there were no difference between type II and type III clasped thumb as regards the pathological findings, severity, the operative procedures, the treatment protocol and the operative results. Properly planned treatment gives satisfactory results.  相似文献   
7.
8.

Background and Aims  

As our population ages and life expectancy increases the number of people aged over 80 and more referred for cardiac surgery is growing. This study sought to identify the outcome of aortic valve replacement (AVR) in octogenarians.  相似文献   
9.
10.
The clinical, biochemical and pathological features of 31 patients with thyroid carcinoma managed at Hospital Universiti Sains Málaysia, Kubang Kerian from 1985 to 1989 were analyzed. There were 25 females and 6 males. The types of carcinoma were: papillary-17 cases; follicular-10 cases; medullary-2 cases and anaplastic-2 cases. For papillary carcinoma the mean age of the patients was 52.9 years. For follicular carcinoma the mean age was 48.3 years, for medullary carcinoma, 48.5 years and for anaplastic, 74.5 years. All patients had pre-existing goitre except for 2 and most presented with advanced disease. The mean duration of symptoms for papillary carcinoma was 3.7 years, follicular carcinoma 1.6 years, medullary carcinoma 13.5 years and anaplastic carcinoma 6 months. 12 patients presented with goitre of increasing size; 9 had compression symptoms; 4 presented with cervical lymph node enlargement and 6 presented with bony pains of whom 2 had paraplegia. None of the patients were ever thyrotoxic or hypothyroid. Treatment in general was unsatisfactory because of patients' non-acceptance of surgery and/or radioactive iodine.  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