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   25001篇
  免费   1761篇
  国内免费   65篇
耳鼻咽喉   344篇
儿科学   835篇
妇产科学   389篇
基础医学   3024篇
口腔科学   616篇
临床医学   2665篇
内科学   4684篇
皮肤病学   346篇
神经病学   2269篇
特种医学   938篇
外科学   4202篇
综合类   353篇
一般理论   24篇
预防医学   2120篇
眼科学   529篇
药学   1845篇
中国医学   19篇
肿瘤学   1625篇
  2023年   123篇
  2022年   185篇
  2021年   494篇
  2020年   279篇
  2019年   509篇
  2018年   578篇
  2017年   396篇
  2016年   420篇
  2015年   507篇
  2014年   776篇
  2013年   1078篇
  2012年   1673篇
  2011年   1664篇
  2010年   938篇
  2009年   854篇
  2008年   1553篇
  2007年   1581篇
  2006年   1592篇
  2005年   1582篇
  2004年   1483篇
  2003年   1289篇
  2002年   1209篇
  2001年   344篇
  2000年   369篇
  1999年   349篇
  1998年   293篇
  1997年   208篇
  1996年   188篇
  1995年   176篇
  1994年   174篇
  1993年   157篇
  1992年   234篇
  1991年   239篇
  1990年   214篇
  1989年   224篇
  1988年   230篇
  1987年   221篇
  1986年   195篇
  1985年   201篇
  1984年   170篇
  1983年   162篇
  1982年   126篇
  1981年   128篇
  1980年   117篇
  1979年   137篇
  1978年   115篇
  1977年   112篇
  1975年   103篇
  1974年   92篇
  1973年   95篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
72.
73.
A 3-year-old boy, who developed the signs and symptoms characteristic of Kawasaki disease, is described. The child also had an 8 cm tender hepatomegaly. Hydrops of the gallbladder could not be shown. Liver biopsy showed marked infiltration of inflammatory cells, including neutrophil and eosinophil leucocytes in the portal tracts involving the periphery of the portal arteries and veins, and acute inflammation of the bile ducts with neutrophil and eosinophil infiltration of the walls. Overt cholangitis has been described only once before in Kawasaki disease, when a viral agent was suggested as being important in the pathogenesis. Although the clinical and laboratory findings in cases of Kawasaki disease clearly suggest an acute infection--as they did in this case--no aetiological agent has yet been incriminated. The possibility of a drug-induced auto-allergic or hypersensitivity state is considered. Evidence for such a state includes a history of drug administration, pathological findings similar to peri-arteritis nodosa--a condition often associated with a hypersensitivity state--the presence of eosinophils in the lesions and a response to treatment with aspirin, a drug known to ameliorate hypersensitivity states.  相似文献   
74.
Ultrasonography of rotator cuff tears: a review of 500 diagnostic studies   总被引:1,自引:0,他引:1  
Ultrasonography of the rotator cuff has been shown to be of value in diagnosing rotator cuff tears. This report summarizes our experience with our first 500 diagnostic examinations. All patients were examined in the hyperextended internal rotation view with commercially available high-resolution real-time ultrasound equipment. Patients were diagnosed as having a rotator cuff tear if a focal echogenic lesion or a defect within the rotator cuff was identified. This study confirmed the value of ultrasonography for the diagnosis of rotator cuff tears. Accuracy, sensitivity, and specificity all exceeded 90%, and correlated with surgical findings. This was better than arthrography in the same patient population. Ultrasound is an accurate noninvasive method of examining the rotator cuff for the presence of tears. We suggest that rotator cuff ultrasonography is the procedure of choice for the diagnosis of tears if adequate instrumentation is available.  相似文献   
75.
Fractures of the epiphyseal plate are considered rare when compared with the more prevalent injuries found in competitive sports, but the complications associated with this type of trauma are a major concern. The factors affecting the success or failure of healing include the severity of injury, patient age, and the type and expedience of treatment. This case study examines the clinical presentation and treatment of a 15-yr-old high school football player who sustained a displaced, distal femoral epiphyseal Salter II fracture. Primary treatment consisted of nonmanipulative, nonweight bearing knee immobilization. The treatment resulted in malunion, pain, decreased range of motion and physical deformity; therefore, the patient sought a second opinion. On physical exam, the displacement and rotational deformity of the fracture site were unacceptable. The fracture was treated 20 days post-injury via open reduction with internal fixation. On follow-up, the athlete demonstrated radiographic healing, normal physical exam, and no significant leg length discrepancy or deformity. The athlete successfully returned to full competitive sport activity.  相似文献   
76.
Pre-excitation disorders have an estimated prevalence of 0.15 per cent. Advances in electrophysiological mapping and the increasing sophistication of surgical techniques have resulted in an increasing role for definitive surgical treatment. A retrospective chart review of 181 patients undergoing 197 procedures for surgical ablation of accessory atrioventricular pathways between June 1981 to June 1986 was performed. Mean age of the patients was 30 years (range 6-66) with a preponderance of males (59 per cent). Associated cardiac disease was found in 18 (9.9 per cent) patients. Induction of anaesthesia employed either a barbiturate-relaxant (83 per cent) or a narcotic-benzodiazepine-relaxant (17 per cent) and was uneventful in all cases. In 14 per cent of cases a pure narcotic relaxant technique was employed for maintenance of anaesthesia, whereas a balanced technique with isoflurane (29 per cent), enflurane (34 per cent), or halothane (22 per cent) was utilized for the remainder. Muscle relaxation was provided by d-tubocurarine in 35 (18 per cent) procedures and pancuronium in the remaining 162 (82 per cent) procedures. There was no significant correlation between intraoperative arrhythmias and type of anaesthetic used. Although recognizing the potential for malignant arrhythmias, our experience (within the confines of a retrospective analysis) suggests that the majority of these patients can be managed successfully using standard anaesthetic techniques.  相似文献   
77.
78.
PURPOSE: Titanium plates and monocortical screws are commonly used to stabilize the mandible following sagittal split ramus osteotomies. Despite widespread use of this type of fixation, there is a paucity of large studies evaluating the infection rate and need for hardware removal. MATERIALS AND METHODS: This study is a retrospective cohort evaluation of 1,066 consecutive mandibular sagittal ramus osteotomies in 533 patients, performed between January 2002 and December 2003. All osteotomies were stabilized with 4-hole miniplates and 2.0 mm x 5.0 mm monocortical screws. Study variables included disturbances of wound healing, age, gender, plate and screw position, direction of mandibular movement, adjunctive procedures performed, and the patient's medical history. Data were collected by chart and radiographic review. The above variables were analyzed using Fisher's exact test, Chi-square, Cochran-Armitage Trend Test, and multiple logistic regression. RESULTS: Of 533 patients 26% (138) demonstrated wound healing problems. This occurred in 15% of all 1,066 osteotomy sites. 6.5% of plates required removal in 10% of patients. In no case did disturbance of wound healing or plate removal result in non-union or relapse of the osteotomy. Wound healing problems were fewer when mandibular osteotomies were done in conjunction with maxillary surgery (18.9% versus 29.1%). Disturbances of wound healing were not related to the direction of movement of the mandible and were lower when hardware was placed closer to the inferior border. CONCLUSION: An overall low incidence (6.5%) of hardware infection requiring plate removal was found in this study. Screw proximity to the osteotomy site did not correlate with higher rates of healing problems, but there was a statistically significant trend of fewer disturbances of healing when the hardware was placed closer to the inferior border of the mandible.  相似文献   
79.
Light curing of composite resin material beneath orthodontic brackets is common in clinical orthodontics. Experiences with composite resins and high-intensity lights indicate some advantages to staged curing of the composite. In this study, the shear/peel bond strength of orthodontic brackets bonded to bovine enamel and cured with a pulsed xenon plasma arc light was compared with that of bonds cured with a conventional tungsten-quartz-halogen light and a nonpulsed xenon plasma arc light. The pulsed light provided less light energy than the nonpulsed lights. A small and a larger light-guide tip were used with the pulsed xenon plasma arc light. Three different orthodontic composite resin adhesives were tested with each light. The pulsed xenon plasma arc light resulted in either the same or decreased shear/peel bond strength when compared with the nonpulsed lights. There appeared to be no advantage to the use of a pulsed xenon plasma arc light in bonding orthodontic brackets. Results from using either a small or a large light-guide tip varied with the adhesive tested.  相似文献   
80.
Monoclonal antibody MAB-T88 is a human monoclonal immunoglobulin M antibody directed at the lipopolysaccharide of gram-negative bacteria. In this study, nine patients who were expected to become neutropenic from antineoplastic chemotherapy received an infusion of MAB-T88, three patients at each of three doses: 1, 4, and 8 mg/kg of body weight. MAB-T88 was shown to be safe, with an effective half-life in plasma of 25.4 h, and no patient developed immunoglobulin G antibody to MAB-T88.  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