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   4109篇
  免费   172篇
  国内免费   12篇
耳鼻咽喉   18篇
儿科学   178篇
妇产科学   56篇
基础医学   505篇
口腔科学   81篇
临床医学   317篇
内科学   765篇
皮肤病学   74篇
神经病学   307篇
特种医学   115篇
外科学   561篇
综合类   98篇
一般理论   1篇
预防医学   238篇
眼科学   216篇
药学   473篇
中国医学   24篇
肿瘤学   266篇
  2023年   36篇
  2022年   99篇
  2021年   164篇
  2020年   87篇
  2019年   94篇
  2018年   126篇
  2017年   82篇
  2016年   113篇
  2015年   127篇
  2014年   145篇
  2013年   187篇
  2012年   301篇
  2011年   299篇
  2010年   160篇
  2009年   135篇
  2008年   207篇
  2007年   226篇
  2006年   200篇
  2005年   172篇
  2004年   155篇
  2003年   138篇
  2002年   146篇
  2001年   121篇
  2000年   104篇
  1999年   74篇
  1998年   31篇
  1997年   28篇
  1996年   43篇
  1995年   16篇
  1994年   6篇
  1993年   12篇
  1992年   31篇
  1991年   32篇
  1990年   39篇
  1989年   45篇
  1988年   40篇
  1987年   36篇
  1986年   29篇
  1985年   29篇
  1984年   25篇
  1983年   22篇
  1982年   15篇
  1981年   11篇
  1980年   14篇
  1979年   24篇
  1977年   13篇
  1974年   9篇
  1973年   6篇
  1971年   7篇
  1970年   9篇
排序方式: 共有4293条查询结果,搜索用时 0 毫秒
71.

Introduction

Thoracic trauma comprises 10–15 % of all traumas. The incidence and etiological pattern of chest trauma varies from region to region and is related to cultural and socio-political circumstances. This paper details our experience with thoracic trauma in a North Indian state.

Material & methods

All patients who were hospitalized for thoracic trauma from June 2010 to June 2012 in our hospital were enrolled. Data was collected prospectively and analysed. Factors analysed were age, gender, mode of injury, type of thoracic injury, associated injuries, management modalities, and outcome.

Results

The total number of patients was 250. The male to female ratio was about 10:1. The mean age of patients was 36.62 years. Road Traffic Accident (RTA) was the most common mode of chest injury. Motor-bike accident was the most common type of RTA. Majority of patients were managed with tube thoracostomy (183, 73.2 %). One hundred and eighty nine (75.6 %) patients were discharged after recovery. Ten (4.0 %) patients absconded. In all, 29 (11.6 %) patients died, while 22 (8.8 %) patients left the hospital against medical advice. A significant association between presence of associated injury and outcome was observed (p?<?0.001). We found mortality rate was significantly higher in chest injury associated with neurotrauma and abdominal visceral injury.

Conclusion

Chest trauma is a major health problem since it has high morbidity and mortality rate. The majority of patients with simple chest injuries can be managed by tube thoracostomy. According to our analysis; mortality predictors were: RTAs, blunt chest trauma, unstable hemodynamic status upon arrival, neurotrauma, abdominal visceral injury, flail chest, ventilator use, cardiac contusion and complications of therapy.  相似文献   
72.
BackgroundBone fracture treatment usually involves restoring of the fractured parts to their initial position and immobilizing them until the healing takes place. Drilling of bone is common to produce hole for screw insertion to fix the fractured parts for immobilization. Orthopaedic drilling during surgical process causes increase in the bone temperature and forces which can cause osteonecrosis reducing the stability and strength of the fixation.MethodsA comprehensive review of all the relevant investigations carried on bone drilling is conducted. The experimental method used, results obtained and the conclusions made by the various researchers are described and compared.ResultReview suggests that the further improvement in the area of bone drilling is possible. The systematic review identified several consequential factors (drilling parameters and drill specifications) affecting bone drilling on which there no general agreement among investigators or are not adequately evaluated. These factors are highlighted and use of more advanced methods of drilling is accentuated. The use of more precise experimental set up which resembles the actual situation and the development of automated bone drilling system to minimize human error is addressed.ConclusionIn this review, an attempt has been made to systematically organize the research investigations conducted on bone drilling. Methods of treatment of bone fracture, studies on the determination of the threshold for thermal osteonecrosis, studies on the parameters influencing bone drilling and methods of the temperature measurement used are reviewed and the future work for the further improvement of bone drilling process is highlighted.  相似文献   
73.
Abstract

A rare case of cervical extradural en-plaquc méningothélial meningioma is reported. The magnetic resonance imaging revealed an extradural sheet of tumor encasing the cervical cord from anterior, posterior and right lateral aspects and emerging from the right C3–A intervertebral foramina. Though a differential diagnosis of lymphoma and tubercular granulation tissue were considered, its isointense intensity patterns on T1 and T2 weighted images and the intratumoral calcification on intrathecal contrast computed tomographic scan suggested a meningioma. At surgery, the lesion was fibrous, avascular and densely adherent to the dura. The radiological features and management options of the lesion are discussed. [Neurol Res 2000; 22: 351-353]  相似文献   
74.
75.
76.
A 33 years old female patient presented with posttraumatic pain in the right foot for which radiographs of the right foot was advised. No fracture was detected on radiographs and patient was managed conservatively on medications and posterior splint immobilization. We found coincidentally a short fourth metatarsal and an accessory navicular bone in the right foot radiographs. After 3 weeks of immobilization, she underwent mobilization of the right foot, weight bearing and intensive physiotherapy for 6 weeks. After two months of injury she was still complaining of pain on the plantar aspect of right foot which was diagnosed as metatarsalgia and operated on by excision of the neuroma present in the 3rd web space of the right foot. After surgery she was completely relieved of pain and could do activities well related to the right foot.  相似文献   
77.
BACKGROUND: In order to develop, implement and evaluate policy for reducing maternal mortality, it is essential to study the risk factors associated with maternal deaths. AIMS: The study aims to determine the epidemiological risk factors and its related causes associated with maternal deaths in Delhi slums. MATERIALS AND METHODS: A community-based case-control study was designed, wherein snowball-sampling method was used to identify the maternal deaths (cases) in the community and circular systematic random sampling procedure was used to select the controls from the same area where a maternal death was found. STATISTICAL ANALYSIS: Data on 70 cases and 384 controls that had live births as the outcome of the pregnancy were analyzed. Logistic regression was applied to identify the risk factors. RESULTS: In the study population, most of the deliveries were conducted at home by untrained 'dais.' Cases were mostly illiterate, young, having high parity and no antenatal care taken during pregnancy (P CONCLUSIONS: The study findings suggest that women should be educated about the importance of antenatal registration and regular checkups. Untrained 'dais' should be trained to recognize the obstetric complications at an early stage and refer high-risk cases for adequate management. These preventive measures could help in reducing maternal mortality at the community level.  相似文献   
78.
Abstract

Developing drug formulations for poorly water-soluble drugs is a major challenge for pharmaceutical industries as the poor water solubility limits bioavailability of these drugs. Production of nanoparticles/microparticles of these drugs is one of the ways to improve dissolution rates by increasing interfacial area for dissolution. Curcumin, a compound obtained from the rhizome of curcuma longa (turmeric roots), is a pharmaceutically viable molecule. However, poor aqueous solubility limits its therapeutic use. In this work, we report studies conducted to continuously produce aqueous suspensions of curcumin nano/micro particles. Influence of process parameters such as ultrasound, additives, and solvent to antisolvent ratio on polymorphic outcome and morphology of precipitated particles has been investigated. Ultrasound was found to greatly influence the polymorphic form and the morphology of precipitated particles. Nucleation rates, mixing time, and solid–liquid interfacial energies were also estimated to understand the effect of various processing parameters on the precipitation process.  相似文献   
79.
Abstract

The objective of this study was to improve the disintegration and dissolution characteristics of a highly water-soluble tablet matrix by altering the manufacturing process. A high disintegration time along with high dependence of the disintegration time on tablet hardness was observed for a high drug loading (70% w/w) API when formulated using a high-shear wet granulation (HSWG) process. Keeping the formulation composition mostly constant, a fluid-bed granulation (FBG) process was explored as an alternate granulation method using a 2(4?1) fractional factorial design with two center points. FBG batches (10 batches) were manufactured using varying disingtegrant amount, spray rate, inlet temperature (T) and atomization air pressure. The resultant final blend particle size was affected significantly by spray rate (p?=?.0009), inlet T (p?=?.0062), atomization air pressure (p?=?.0134) and the interaction effect between inlet T*spray rate (p?=?.0241). The compactibility of the final blend was affected significantly by disintegrant amount (p?<?.0001), atomization air pressure (p?=?.0013) and spray rate (p?=?.05). It was observed that the fluid-bed batches gave significantly lower disintegration times than the HSWG batches, and mercury intrusion porosimetry data revealed that this was caused by the higher internal pore structure of tablets manufactured using the FBG batches.  相似文献   
80.
We present a case of cyanotic congenital heart disease with left common carotid artery agenesis in the setting of the right aortic arch highlighting the potential implications in management.  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