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   31869篇
  免费   1677篇
  国内免费   185篇
耳鼻咽喉   229篇
儿科学   736篇
妇产科学   461篇
基础医学   3992篇
口腔科学   829篇
临床医学   2153篇
内科学   8268篇
皮肤病学   657篇
神经病学   2527篇
特种医学   1098篇
外科学   5232篇
综合类   170篇
一般理论   1篇
预防医学   790篇
眼科学   541篇
药学   2258篇
中国医学   46篇
肿瘤学   3743篇
  2023年   263篇
  2022年   502篇
  2021年   796篇
  2020年   441篇
  2019年   596篇
  2018年   779篇
  2017年   556篇
  2016年   630篇
  2015年   688篇
  2014年   863篇
  2013年   1015篇
  2012年   1618篇
  2011年   1682篇
  2010年   987篇
  2009年   821篇
  2008年   1422篇
  2007年   1653篇
  2006年   1527篇
  2005年   1563篇
  2004年   1501篇
  2003年   1384篇
  2002年   1412篇
  2001年   1007篇
  2000年   967篇
  1999年   935篇
  1998年   387篇
  1997年   301篇
  1996年   339篇
  1995年   208篇
  1994年   202篇
  1993年   186篇
  1992年   563篇
  1991年   519篇
  1990年   529篇
  1989年   474篇
  1988年   450篇
  1987年   444篇
  1986年   381篇
  1985年   401篇
  1984年   287篇
  1983年   199篇
  1979年   215篇
  1978年   145篇
  1977年   144篇
  1974年   131篇
  1971年   136篇
  1970年   132篇
  1969年   129篇
  1968年   139篇
  1967年   141篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
We report 3 cases of müllerian duct cyst. Percutaneous puncture, aspiration and instillation of a sclerosing agent under ultrasound guidance was performed in each case. Ultrasound is valuable in the diagnosis is of cysts in the region of the prostate and seminal vesicles. Aspiration under ultrasound guidance would also be of therapeutic value.  相似文献   
72.
The local hyperthermochemotherapy for pleural carcinomatosis]   总被引:2,自引:0,他引:2  
Local hyperthermochemotherapy was performed in 17 cases to control malignant effusion and intrathoracic disseminated lesions. Of these 15 patients, 11 cases primary lung cancer, 4 cases metastatic lung cancer had pleural carcinomatosis and 2 cases were malignant diffuse mesotheliomas. The procedure was radiofrequency hyperthermia (13.56 MHz) maintaining the peripleural temperature at 42-43 degrees C for 45-60 minutes, combined simultaneously with the intrathoracic administration of cisplatin (1-2 mg/m2, bolus) through a thoracic double lumen trocar tube. The treatment was repeated from 2 to 4 times at 7-day intervals. In 14 cases (87.5%) complete or partial response according to the criteria of the Japan Lung Cancer Society were obtained. There were 2 cases of no change and one case that was impossible to evaluate. In one lung cancer case, the disappearance of pleural disseminated lesions was confirmed by flexible thoracoscopy after the procedure. In 12 cases, there were abdominal complaints due to side effects of the hyperthermochemotherapy, such as vomiting and nausea, but these symptoms were milder than those caused by intravenous injection of anti-cancer agents, for example cisplatin, in conventional chemotherapy treatment. The median survival time and 2 years survival of the patients with the present procedure were 15 months and 41.7% respectively. Although distant metastases appeared in most cases, none had local recurrence and particularly noteworthy pleural effusion was well controlled. The above experience suggested that the local hyperthermochemotherapy is useful to control pleural effusion and can improve the quality of life of patients with pleural carcinomatosis.  相似文献   
73.
Infective endocarditis of the mitral area accompanied by anorexia nervosa is extremely rare. A 34-year-old Japanese woman presented with high fever and a heart murmur that had developed over the previous 2-month period. Echocardiography revealed mitral regurgitation and vegetation attached to the anterior mitral leaflet, which had markedly prolapsed to the left atrium. We removed the vegetation with a small part of the anterior mitral leaflet and successfully repaired the mitral valve. The patient showed good recovery, and the mitral regurgitation and left ventricular chamber size had satisfactorily decreased at 2 months after the operation.  相似文献   
74.
An accurate and reproducible colorimetric assay was established to determine the concentration of basic fibroblast growth factor (bFGF) or bFGF-like activity in culture media and biological fluids. Fetal bovine heart endothelial cell line ATCC CRL 1395 was used as the bFGF-dependent cell line. The proliferation-stimulating activity of bFGF was determined by measuring the amount of formazan formed by the mitochondrial enzymes from a tetrazolium salt, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), instead of counting the viable cell numbers or measuring the incorporation of [3H]-thymidine. The addition of 250 ng/mL of heparin to the culture medium resulted in about a tenfold increase in the proliferation-stimulating activity of bFGF and allowed the detection of as low as 10 pg/mL of bFGF. Heparin also resulted in much smaller inter- and intraassay variations. The bFGF concentrations determined by this colorimetric assay correlated well with those determined by both the [3H]-thymidine incorporation assay using BALB/c 3T3 fibroblast cells (r = 0.998) and the cell number count assay (r = 0.996). This assay can be adapted to quantify bFGF or bFGF-like activity in tissue culture media and biological fluids such as plasma and organ extracts.  相似文献   
75.
76.
To examine the clinical characteristics of methamphetamine (MAP) psychosis in Japan, we evaluated 104 patients with MAP psychosis (80 men and 24 women) admitted to the closed psychiatric units of Tokyo Metropolitan Matsuzawa Hospital between 1988 and 1991. There has recently been a steep increase in the number of admissions for MAP psychosis, reflecting the growth of the epidemic of MAP abuse in Japan. Although more than half of the patients were discharged within one month, 16 patients were hospitalized for more than 3 months. Most of the patients showed paranoid psychotic state similar to schizophrenia, consistent with previous reports. Despite the abstinence from MAP and antipsychotic medication, psychotic symptoms tended to persist in some of the patients. The etiological role of MAP psychosis in the development of long-lasting psychotic state was discussed.  相似文献   
77.
Giant or large intracranial aneurysms are the vascular neurosurgeon's greatest challenge. At our department, we have treated one hundred and thirty nine patients with giant or large intracranial aneurysms between 1975 and 2001. These included 37 partially thrombosed giant aneurysms. 75 aneurysms were giant (> 2.5 cm) and 64 were large aneurysms (2-2.5 cm). Three-dimensional computed tomography angiograms were performed in patients besides MRI angiography and digital subtraction angiography. These were found to be very valuable in the preoperative assessment of surgical anatomy of the aneurysm with respect to the branch arteries and perforators origin besides knowing the relations to the skull base. With our experience in surgical treatment of these 139 cases, we find that the basic technique is trapping and evacuation and not just clipping of the aneurysm neck but also reconstruction of the artery bearing the aneurysm, especially with wide-necked aneurysms. Use of multiple clipping, tandem clipping or dome clipping as per the intraoperative situation, is very helpful in dealing with giant aneurysms as also is the use of different types of clips like fenestrated clip with straight clip (combination clipping), booster clip, dome clips etc. While selecting surgical strategy for partially thrombosed giant aneurysm, securing the neck is most important. If the neck is too narrow to reconstruct, aneurysmectomy with anastomosis is one of the surgical strategies. An extracranial intracranial bypass should be considered in cases where clipping or parent artery ligation is expected to be associated with compromise of cerebral circulation.  相似文献   
78.
Optical technological innovations enable us to visualize cellular nuclei endoscopically. Herein is described a protocol design for a multicenter study for the ex vivo evaluation of endocytoscopy. The present study was performed by the Endoscopy Forum Japan study group.  相似文献   
79.
The aim of this study was to fabricate an artificial bile duct for the development of a new treatment for biliary diseases. Eighteen hybrid pigs were implanted with a bile duct organoid unit (BDOU) made of a bioabsorbable polymer. Twelve of the transplanted BDOUs had been seeded with autologous bone marrow cells (BMCs) in advance. Six animals, the controls, were grafted with the scaffold alone with no BMCs seeded. The common bile duct was cut, the hepatic cut end of the native common bile duct was anastomosed to the BDOU and the other end was anastomosed to the duodenum. The controls underwent a similar operation. The neo-bile duct was removed at pre-determined time points and investigated histologically. All 18 recipient pigs survived until their sacrifice at 6 weeks, 10 weeks or 6 months. Histological examination revealed incomplete epithelialization of the neo-bile duct at 6 weeks and 10 weeks after transplantation. At 6 months, the organoid exhibited a morphology almost identical to that of the native common bile duct. No differences were found between the controls and BMC-seeded pigs. These results show that the artificial bile duct thus fabricated can serve as a substitute for the native bile duct.  相似文献   
80.
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms.  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