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   6629篇
  免费   374篇
  国内免费   29篇
耳鼻咽喉   95篇
儿科学   381篇
妇产科学   98篇
基础医学   782篇
口腔科学   104篇
临床医学   461篇
内科学   1485篇
皮肤病学   96篇
神经病学   476篇
特种医学   123篇
外科学   960篇
综合类   183篇
一般理论   6篇
预防医学   366篇
眼科学   219篇
药学   697篇
中国医学   80篇
肿瘤学   420篇
  2023年   41篇
  2022年   54篇
  2021年   251篇
  2020年   108篇
  2019年   159篇
  2018年   222篇
  2017年   151篇
  2016年   162篇
  2015年   190篇
  2014年   270篇
  2013年   363篇
  2012年   490篇
  2011年   508篇
  2010年   289篇
  2009年   257篇
  2008年   393篇
  2007年   369篇
  2006年   315篇
  2005年   326篇
  2004年   235篇
  2003年   205篇
  2002年   226篇
  2001年   103篇
  2000年   116篇
  1999年   101篇
  1998年   74篇
  1997年   38篇
  1996年   38篇
  1995年   30篇
  1993年   30篇
  1992年   55篇
  1991年   71篇
  1990年   71篇
  1989年   56篇
  1988年   46篇
  1987年   55篇
  1986年   42篇
  1985年   58篇
  1984年   45篇
  1983年   37篇
  1982年   24篇
  1980年   19篇
  1979年   30篇
  1978年   23篇
  1977年   27篇
  1975年   21篇
  1973年   31篇
  1972年   20篇
  1971年   27篇
  1969年   21篇
排序方式: 共有7032条查询结果,搜索用时 359 毫秒
71.
72.
Prakash A  Markham A 《Drugs》1999,57(3):383-408
Oral delayed-release mesalazine is an enteric-coated formulation which releases mesalazine in the terminal ileum and colon. Up to 74% of patients with mild to moderately active ulcerative colitis experience endoscopic or symptomatic improvement (including remission) or both when treated with oral delayed-release mesalazine 2.4 to 4.8 g/day. There is a trend towards a better response in patients receiving higher daily dosages of oral delayed-release mesalazine, especially in patients with active distal disease. In patients with left-sided ulcerative colitis, oral balsalazide 6.75 g/day appears to be more effective than oral delayed-release mesalazine 2.4 g/day, but a higher dosage of oral delayed-release mesalazine 4.8 g/day may provide additional benefit in these patients. Oral delayed-release mesalazine 0.8 to 4.4 g/day appears to be as effective as sulfasalazine 2 to 4 g/day, prolonged-release mesalazine 1.5 g/day or balsalazide 3 g/day in maintaining remission in patients with ulcerative colitis. The optimal dosage of oral delayed-release mesalazine for the maintenance of remission is unclear. However, oral delayed-release mesalazine 1.6 g/day with rectal mesalazine 4g, administered twice weekly, was more effective than oral drug alone in maintaining remission in patients at high risk of relapse. In patients with left-sided or distal disease oral olsalazine 1 g/day appeared to be superior to oral delayed-release mesalazine 1.2 g/day for maintenance of symptomatic remission. Limited data in patients with Crohn's disease have shown oral delayed-release mesalazine 0.4 to 4.8 g/day to be an effective therapy for active disease (remission in up to 45% of patients) and for quiescent disease (relapse in 34% of recipients over a duration of up to 12 months). Preliminary data indicate that oral delayed-release mesalazine 2.4 g/day is effective in preventing postoperative recurrence of Crohn's disease. Oral delayed-release mesalazine is effective and well tolerated in sulfasalazine-intolerant patients with ulcerative colitis or Crohn's disease. CONCLUSIONS: Oral delayed-release mesalazine is effective in patients with mild to moderately active or quiescent ulcerative colitis. Available data suggest that patients with left-sided or distal ulcerative colitis are likely to require higher daily dosages of oral delayed-release mesalazine or supplementation with rectal mesalazine. Oral delayed-release mesalazine also appears to be effective in active and quiescent Crohn's disease. The drug is well tolerated and it appears to be effective in sulfasalazine-intolerant patients.  相似文献   
73.
We have applied advanced real-time techniques in softwave, that are intensively used in critical areas like space research and defence applications, to realise an Integrated Real-Time Respiratory Monitoring System at the Thorax Anesthesiology, Academic Hospital Rotterdam. The system is called the SERVO WINDOW —a window to the servo ventilator. The heart of the system is a real-time kernel that uses preemptive scheduling to achieve multitasking on a IBMPC compatible hardware platform. To the clinician this means that he gets all relevant information from one source i.e. the Respiratory Workstation. The waveforms of the airway pressure, airway flow and the expired CO2 curve are displayed continuously on the screen. The Vector Loops like Pressure Volume, Flow Pressure and Flow Volume loops are also available in addition to the lung mechanics parameters like Expiratory and Inspiratory Resistances, Compliance, Peak Pressure, PEEP, etc. The Single Breath Diagram i.e. expired CO2 concentration versus volume and dead space ventilation is also calculated. The blood gas analysis data is plotted in convenient diagrams like the O2–CO2 diagram, Oxygen Chart, etc. The trend of all these parameters are available with a granularity of one minute. An industry standard laser printer is used for report generation to produce reports of the real-time waveforms, parameter values and the trends. User interface is through easy menus with the traditional keyboard, touchscreen including keyborad on screen for data entry and the mouse.  相似文献   
74.
75.
76.
BACKGROUND AND PURPOSE: Single agent mitomycin c (MMC) has been shown to improve the outcome of radiotherapy in single institution trials. In order to confirm these findings in a broader worldwide setting, the International Atomic Energy Agency (IAEA) initiated a multicentre trial randomising between radiotherapy alone versus radiotherapy plus MMC. MATERIAL AND METHODS: Patients with advanced head and neck cancer were treated with primary curative radiotherapy (66 Gy in 33 fractions with five fractions per week) +/-a single injection (15 mg/m(2)) of MMC at the end of the first week of radiotherapy. Stratification parameters were tumour localization, T-stage, N-stage, and institution. A total of 558 patients were recruited in the trial from February 1996 to December 1999. Insufficient accrual and reporting led to the exclusion of three centres. The final study population consisted of 478 patients from seven centres. Patients had stage III (n=223) or stage IV (n=255) squamous cell carcinoma of the oral cavity (n=230), oropharynx (n=140), hypopharynx (n=65) or larynx (n=43). Prognostic factors like age, gender, site, size, differentiation and stage were well balanced between the two arms. RESULTS: The haematological side effects of MMC were very modest (<5% grade 3-4) and did not require any specific interventions. Furthermore, MMC did not enhance the incidence or severity of acute and late radiation side effects. Confluent mucositis and dry skin desquamation was common, occurring in 56% and 62% of patients, respectively. The overall 3-year primary locoregional tumour control, disease-specific and overall survival rates were 19, 36 and 30%, respectively. Gender, haemoglobin drop, tumour site, tumour and nodal stage were significant parameters for loco-regional tumour control. There was no significant effect of MMC on locoregional control or survival, except for the 161 N0 patients, where MMC resulted in a better loco-regional control (3-year estimate 16% vs. 29%, P=0.01). CONCLUSIONS: The study did not show any major influence of MMC on loco-regional tumour control, survival or morbidity after primary radiotherapy in stage III-IV head and neck cancer except in N0 patients where loco-regional control was significantly improved.  相似文献   
77.
Solitary extramedullary plasmacytoma is a rare tumour with radiotherapy playing an important role in its management. This report describes the case history of a man with a solitary extramedullary plasmacytoma at an extremely rare site, the premaxilla, that posed certain diagnostic and therapeutic dilemmas. The patient underwent surgery followed by postoperative radiotherapy. The use of two modalities of treatment for this localized tumour has been justified by briefly reviewing the literature and defining the various prognostic factors. These prognostic factors in turn should guide the treatment of these uncommon tumours.  相似文献   
78.
Otoendoscopy enables viewing of different angles of the tympanomastoid area and approach to them for better prognosis. A comparative study of post-operative mastoid cavities has been done using the Hopkin’s rod telescope, Otoscope and microscope. Various procedures have also been done successfully on the mastoid cavity using the telescope on an outdoor basis.  相似文献   
79.
A series of 14 parapharyngeal tumours has been studied with regard to their symptology, pre-operative evaluation and surgical management. High resolution computed tomography is now the best initial diagnostic study because it helps to determine the size and extent of the tumour, differentiate tumours of parotid and extraparotid origin, demonstrate degree of tumour vascularity, separate benign from malignant lesions, plan the surgical approach and predict prognosis.  相似文献   
80.
A 23 years old male presented with a soft cystic mass in the left paralaryngeal space since 3 months. Indirect laryngoscopy revealed a bulging of the left lateral pharyngeal wall. Histopathologic al examination of the biopsy proved it to be a synovial sarcoma. The case is the seventh case reported in literature.  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