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   13419篇
  免费   686篇
  国内免费   53篇
耳鼻咽喉   113篇
儿科学   891篇
妇产科学   294篇
基础医学   1345篇
口腔科学   290篇
临床医学   842篇
内科学   2697篇
皮肤病学   346篇
神经病学   727篇
特种医学   374篇
外国民族医学   1篇
外科学   2306篇
综合类   350篇
一般理论   13篇
预防医学   568篇
眼科学   599篇
药学   1313篇
中国医学   61篇
肿瘤学   1028篇
  2023年   97篇
  2022年   206篇
  2021年   501篇
  2020年   252篇
  2019年   354篇
  2018年   425篇
  2017年   314篇
  2016年   385篇
  2015年   394篇
  2014年   545篇
  2013年   719篇
  2012年   1033篇
  2011年   1091篇
  2010年   584篇
  2009年   454篇
  2008年   749篇
  2007年   718篇
  2006年   611篇
  2005年   544篇
  2004年   524篇
  2003年   418篇
  2002年   380篇
  2001年   295篇
  2000年   294篇
  1999年   247篇
  1998年   100篇
  1997年   67篇
  1996年   84篇
  1995年   66篇
  1994年   49篇
  1993年   45篇
  1992年   117篇
  1991年   162篇
  1990年   126篇
  1989年   107篇
  1988年   107篇
  1987年   75篇
  1986年   85篇
  1985年   89篇
  1984年   65篇
  1983年   68篇
  1979年   66篇
  1978年   44篇
  1977年   35篇
  1975年   34篇
  1973年   38篇
  1972年   41篇
  1971年   44篇
  1969年   32篇
  1968年   44篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
Severe lower limb defects in exstrophy of the cloaca   总被引:1,自引:0,他引:1  
We present here a patient with exstrophy of the cloaca associated with severe lower limb defects. The limb malformations include, on the right, a split foot with distal separation of the tibia and fibula, and on the left, attachment of the lower half of the left leg with a two-toed foot at nearly a right angle to the mid left thigh. A review of the literature indicates that 17-26% of patients with cloacal exstrophy also have lower limb defects. We hypothesize that cloacal exstrophy and associated lower limb defects have a related pathogenesis and that both are related to deficiencies of caudal mesoderm or mesodermal differentiation signals. More cases of exstrophy of the cloaca with limb defects need to be reported to better characterize the limb anomalies and to more precisely determine their frequency.  相似文献   
103.
104.
Sorbitol Intolerance in Adults   总被引:3,自引:0,他引:3  
Sorbitol is a commonly used sugar substitute in "sugar-free" food products. Although sorbitol intolerance manifested by abdominal pain, bloating, and diarrhea has been observed in children, it has not been well documented in adults. Forty-two healthy adults (23 whites, 19 nonwhites) participated in this study. After ingestion of 10 g of sorbitol solution, end expiratory breath samples were collected at 15-min intervals for 4 h and analyzed for H2 concentration. Clinical sorbitol intolerance was detected in 43% of the whites and 55% of the nonwhites, the difference not being statistically significant. However, severe clinical sorbitol intolerance was significantly more prevalent in nonwhites (32%) as compared to whites (4%). There was a good correlation between the severity of symptoms and the amount of hydrogen exhaled. Dietetic foods, many of them containing sorbitol, are very popular with diabetics and "weight watchers." Based on our observations, we believe that a large number of adults could be suffering from sorbitol-induced nonspecific abdominal symptoms and diarrhea. These symptoms could lead to an extensive diagnostic work-up and lifelong diagnosis of irritable bowel syndrome.  相似文献   
105.
Transport of molecules across tumor vasculature   总被引:16,自引:0,他引:16  
The vascular-extravascular exchange of fluid and solute molecules in a tissue is determined by three transport parameters (vascular permeability, P, hydraulic conductivity, Lp, and reflection coefficient, ); the surface area for exchange, A; and the transluminal concentration and pressure gradients. The transport parameters and the exchange area for a given molecule are governed by the structure of the vessel wall. In general, tumor vessels have wide interendothelial junctions; large number of fenestrae and transendothelial channels formed by vesicles; and discontinuous or absent basement membrane. While these factors favor movement of molecules across tumor vessels, high interstitial pressure and low microvascular pressure may retard extravasation of molecules and cells, especially in large tumors. These characteristics of the transvascular transport have significant implications in tumor growth, metastasis, detection and treatment.  相似文献   
106.
Verma KS  Jain AK  Nagar A  Gupta SR 《Planta medica》1986,52(4):315-317
Macrocarposide has been isolated for the first time as a natural product from the heartwood of PTEROCARPUS MACROCARPUS along with some known compounds. Based on its spectral and chemical evidence, it has been assigned the structure dalbergioidin-6- C-glucoside ( 1).  相似文献   
107.
Lasers in Medical Science - Transurethral endoscopic incision is an established treatment option for management of obstructing ureterocele. It can be performed using monopolar electrocautery or...  相似文献   
108.
A 46-year-old male presented with breathlessness for a few months. He had been operated twice for liver hydatid cysts and once for right pulmonary hydatid cysts at other hospitals. Now he was found to have one hydatid cyst in the upper lobe of the left lung and multiple hydatid cysts adjoining left heart border. On computed tomography (CT) scan chest and echocardiography, it was difficult to ascertain whether these cysts were pulmonary or intrapericardial. Left ventricular ejection fraction (LVEF) was 25%. Enzyme-linked immunosorbent assay (ELISA) was positive for hydatid. Left posterolateral thoracotomy revealed dead hydatid cyst in upper lobe of the lung that was removed. Infected mother hydatid cyst was encountered inside pericardial sac. Scores of daughter hydatid cysts, varying in size from 1 to 30 mm, were scooped out intact from the pericardial cavity. There was significant improvement in cardiac activity, once the tamponade effect of hydatid cyst was removed. Pericardium was about 1 cm thick with lot of purulent and necrotic slough. To prevent future constrictive pericarditis, subtotal pericardiectomy was done. Intrapericardial hydatid cyst should be kept in mind whenever it obscures the heart border and patient has features of cardiac tamponade. Early surgical intervention may be required in these cases.  相似文献   
109.
Covid-19 is a respiratory disease caused by coronavirus 2 (SARS-CoV-2) first identified in Wuhan, China (December 2019). The disease rapidly crossed the barrier of countries, continents and spread globally. Non-pharmaceutical measures such as social distancing, face mask, frequent hand washing and use of sanitizer remained the best available option to prevent the spread of disease. OPD, IPD admissions, elective O. Ts were curtailed. Orthopedic care was only limited to emergency and semi-urgent procedures like necrotizing fasciitis, open fracture, and compartment syndrome. These measures were taken to preserve infrastructure and manpower to manage covid-19 pandemic. The children were thought to have a low susceptibility to covid-19 as compared to an adult. Deferring the patient during pandemic has led to high orthopedic disease burden, morbidity and disease-related sequelae, hence elective care must be resumed with modified hospital infrastructure. Resumption of elective/emergent orthopedic care should be slow, phasic and strategic, much similar to unlocking. Cases must be stratified depending on covid status and severity. Dedicated O.Ts with neutral/negative pressure and HEPA filter for covid positive and suspected patients are to be used. All symptomatic and suspected patients should be investigated for covid-19 by RT-PCR, blood counts and CT scan. Regional anaesthesia should be preferred to General anaesthesia. Power drill/saw/burr/pulse lavage should be minimized to avoid aerosol generation. Postoperatively continuous surveillance and monitoring to be done for covid related symptoms. Medical institutes rapidly shifted to the online mode of education. Blended learning (virtual & physical) and imparting skills have to be continued in post covid phase with equitable distribution of teaching hours to students of different years.  相似文献   
110.
AimsThe purpose of this study was to analyze the clinical outcomes after Eden-Hybinette procedure for revision surgery in recurrent anterior shoulder instability in patients with epilepsy.Materials and MethodsWe retrospectively evaluated eight such patients between 2015 and 2018. Four patients had failed Latarjet/Bristow procedure and two had failed arthroscopic Bankart procedure, while two had history of both the procedures. After medical control of epilepsy, Eden-Hybinette procedure was performed in all patients. WOSI score and Rowe shoulder score was recorded preoperatively and in subsequent post-operative follow-up. A paired t test was used to analyze and compare preoperative and postoperative outcomes and was considered significant if p value was < 0.05.ResultsThe average follow-up was 30 months (range 24–48 months). There was no recurrence of shoulder instability. The mean WOSI score before surgery was 77.3 (range 70–83), which improved to 24.2 (range 19–30) at 24-month follow-up. The mean Rowe score before surgery was 11.3 (range 5–15), which improved to 81.8(range 65–90) at 24-month follow-up. The improvement in WOSI and Rowe score was found to be statistically significant [p value < 0.05]ConclusionsWe conclude that Eden-Hybinette is a useful revision procedure to manage recurrent anterior shoulder dislocation in patients with epilepsy. Optimum medical control of seizure is also an important factor in preventing recurrent shoulder instability  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