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   7657篇
  免费   323篇
  国内免费   48篇
耳鼻咽喉   62篇
儿科学   87篇
妇产科学   101篇
基础医学   845篇
口腔科学   319篇
临床医学   434篇
内科学   2061篇
皮肤病学   67篇
神经病学   451篇
特种医学   126篇
外科学   1411篇
综合类   47篇
预防医学   181篇
眼科学   129篇
药学   719篇
中国医学   23篇
肿瘤学   965篇
  2022年   70篇
  2021年   124篇
  2020年   65篇
  2019年   99篇
  2018年   137篇
  2017年   112篇
  2016年   111篇
  2015年   103篇
  2014年   151篇
  2013年   173篇
  2012年   303篇
  2011年   315篇
  2010年   207篇
  2009年   157篇
  2008年   273篇
  2007年   352篇
  2006年   313篇
  2005年   338篇
  2004年   335篇
  2003年   279篇
  2002年   344篇
  2001年   249篇
  2000年   269篇
  1999年   254篇
  1998年   98篇
  1997年   78篇
  1996年   77篇
  1995年   84篇
  1994年   49篇
  1993年   51篇
  1992年   207篇
  1991年   171篇
  1990年   159篇
  1989年   189篇
  1988年   163篇
  1987年   156篇
  1986年   150篇
  1985年   145篇
  1984年   105篇
  1983年   94篇
  1982年   59篇
  1979年   76篇
  1978年   64篇
  1977年   55篇
  1976年   58篇
  1974年   57篇
  1973年   48篇
  1972年   51篇
  1970年   48篇
  1969年   66篇
排序方式: 共有8028条查询结果,搜索用时 15 毫秒
71.
BACKGROUND: The purpose of this study is to evaluate the efficacy of postoperative adjuvant chemotherapy using uracil and tegafur (UFT) for colorectal cancer. METHODS: In a multicenter trial among 43 institutions for patients who underwent curative resection of Dukes' B or C colorectal cancer, a surgery alone group (control group) and a treatment group (UFT group) to which UFT was administered at 400 mg/day for 2 years following surgery were compared. A total of 320 patients were registered between March 1991 and April 1994, and 289 of these patients were analyzed as a full-analysis set. RESULTS: The 5-year disease-free survival rate was 75.7% in the UFT group and 60.1% in the control group, respectively, and the stratified log-rank test showed the statistical significance ( P=0.0081). This difference was marked in rectal cancer ( P=0.0016) and, in particular, the local recurrence was reduced. No significant difference was observed in the 5-year survival rate. The incidence of adverse reactions on administration of UFT was low, and there was no serious adverse reaction. CONCLUSION: It is suggested that the consecutive administration of UFT at 400 mg/day was an effective and highly safe therapeutic method as postoperative adjuvant chemotherapy for rectal cancer.  相似文献   
72.
We describe a 37-year-old man complaining of right back pain and gait disturbance. He had a big soft tumor on his right back, hemihypertrophy of the right lower extremity, and right thoracic scoliosis. We diagnosed Klippel-Trenaunay-Weber syndrome based on the pathological findings of the soft tumor. Computed tomography (CT) scan revealed severe spinal stenosis due to a hypertrophic vertebral body and facet joint at T7. Treatment by decompression of hypertrophic bone led to complete neurological recovery. To our knowledge, no case has been reported of Klippel-Trenaunay-Weber syndrome with myelopathy which originated from thoracic scoliosis with a hypertrophic facet joint and vertebral body. We suggest that the cause of myelopathy in Klippel-Trenaunay-Weber syndrome originated not only from arteriovenous fistula, medullary angioma, and extradural hemangioma but also vertebral hypertrophy with scoliosis.  相似文献   
73.
Purpose: We examined the feasibility and effectiveness of bronchial arterial infusion (BAI) as induction chemotherapy before surgery for locally advanced non-small cell lung cancer (NSCLC). Methods: Eighteen patients with locally advanced NSCLC were given BAI consisting of cis-diamminedichloroplatinum (CDDP) (50–100 mg/m2) as induction chemotherapy before surgery (induction BAI). Six patients with clinical stage IIIA cancer had bulky N2 metastatic lymph nodes, and 12 patients with clinical stage IIIB cancer had T4 disease. Results: Of the 18 patients, 12 (67%) showed a partial response to the BAI therapy. Standard pulmonary resection was performed in 5 patients, pulmonary resection with the combined resection of adjacent organs was performed in 10 patients, and pulmonary resection with carinal resection and reconstruction was performed in 3 patients. Complete resection was possible in 14 patients (78%). There were no serious BAI therapy-related complications or postoperative deaths. The 5-year survival rate of the 18 patients was 35.7% and the median survival time (MST) was 19.4 months. Survival was better when complete resection was achieved after the induction BAI, especially in patients with stage IIIB (T4) disease. Conclusion: Based on our preliminary findings, BAI with CDDP as induction chemotherapy is feasible and may be an effective therapeutic modality for locally advanced NSCLC. Received: July 26, 2001 / Accepted: March 5, 2002  相似文献   
74.
To evaluate the optimum treatment strategy for metastatic adrenal tumors derived from non-small cell lung cancer (NSCLC), we retrospectively analyzed 17 consecutive cases (8 resection cases: 4 synchronous and 4 metachronous: 9 non-resection cases: 3 synchronous and 6 metachronous) who received surgical resection for NSCLC. The patients included 12 males and 5 females with a mean age of 63.9 years. Of these, 9, 3, 2, 2, and 1 patient (s) were diagnosed as having adenocarcinoma, squamous cell carcinoma, pleomorphic carcinoma, large cell carcinoma, and adenosquamous cell carcinoma, respectively. The mean interval after lung resection and treatment of metachronous adrenal metastasis was 9.9 months. The mean time to progression from treatment of metachronous adrenal metastasis to disease progression was 8.9 months. A survival analysis showed no significant prognostic difference between the patient age, gender, pathological stage, synchronous/metachronous classification, CEA, and site of metastases. However, patients who received an adrenalectomy had a more favorable prognosis. The 2-year survival of patients following resection versus those who did not undergo a resection for adrenal metastasis was 62.5 and 22.8%, respectively. These data indicate that metastatic adrenal tumors should be resected if the patient can tolerate surgery after appropriate selection.  相似文献   
75.
This study aims to investigate the therapeutic and prognostic implications of esophageal cancer in patients with other primary cancer. Between April 1992 and December 2008, in 83 patients underwent surgery for esophageal cancer at our department. Among them, 24 patients (28.9%) had medical history of additional primary cancer. There were 16 metachronous cancers and 8 synchronous cancers. Six patients had antecedent other primary cancers, and subsequent primary cancers developed in 10 patients. The other primary cancers included head and neck cancer in 8 patients, gastric cancer in 8, lung cancer in 6, colorectal cancer in 3, and other cancer in 3. The patients with other primary cancers were both heavy smokers and heavy drinkers in comparison to those without other primary cancers. The post-operative 5-year survival rate in patients with subsequent cancers, antecedent cancers, and synchronous cancers were 100%, 70.0%, and 46.9%. The 5-year survival rate was 33.4% in patients without other primary cancers. A high incidence of multiple primary cancers was observed in patients with esophageal carcinoma but the prognosis of these patients with metachronous cancers are better than that of patient with synchronous cancers and patients without other primary cancers. Post-operative follow up is considered to be necessary for early detection of multiple occurrences of carcinoma, especially in the upper aerodigestive tract.  相似文献   
76.
A 52-year-old woman was referred to our hospital for treatment of urachal cancer. She complained of supurapubic dull pain and gross hematuria. Computed tomography and magnetic resonance imaging showed a non-papillary sessile tumor, which was located on the dome of the bladder and invaded the small intestine. The tumor was diagnosed as Sheldon's stage IIIC urachal cancer. After three courses of neoadjuvant chemotherapy with FOLFOX4 (oxaliplatin, 5-FU and leukovolin), the tumor was reduced from 7 x 6 cm to 5.5 x 5 cm in size. Consequently, the patient underwent an en-bloc resection of the urachal tumor with the dome of the bladder and the parts of the ileum invaded by the tumor. One course of adjuvant chemotherapy (FOLFOX4) was performed. Surgical specimen revealed histologically well differentiated squamous carcinoma and invasion to the propria of the ileum. The surgical margins were negative for the cancer. For 1.5 years after the surgery, no local recurrence or distant metastasis has been observed.  相似文献   
77.
Bone marrow stromal cells support osteoclast differentiation by expressing receptor activator of NF-kB ligand (RANKL). Although several bone marrow stromal cell lines have been established and characterized, the differentiation stage of the supporting cells for osteoclast differentiation remains unclear. We have established several bone marrow stromal cell lines from transgenic mice harboring the temperature-sensitive SV40 large T antigen. Some of these temperature-sensitive bone marrow stromal cell lines (TSB cell lines) support osteoclast differentiation and differentiate into osteoblasts, suggesting that osteoblast precursor cells support osteoclast differentiation. Here we show that the TSB cell lines that support osteoclast differentiation also expressed peroxisome proliferator-activated receptor γ1 (PPARγ1) and were able to differentiate into adipocytes. PPARγ1 is an alternatively spliced form of PPARγ that is responsible for the adipocyte differentiation and expressed in the adipocyte precursor cells. Immunofluorescence analysis of TSB cell lines and primary bone marrow stromal cells by use of anti-PPARγ and anti-RANKL antibodies showed that fluorescent signals for RANKL were observed in the cells that expressed PPARγ. Furthermore, activation of adipocyte differentiation by a PPARγ agonist led to decreased RANKL expression. These results demonstrate that PPARγ1-positive precursor cells for osteoblasts and adipocytes expressed RANKL and supported osteoclastogenesis.  相似文献   
78.
The leakage of tracheal anastomoses is one of the major complications that occurs after tracheal reconstruction. Improved reinforcing methods for anastomoses would thus be clinically useful. To find a better technique, we examined the postoperative would-healing effect of fibrin glue on tracheal anastomosis in the rat. Experimental rats were divided into two groups. In the control group (n = 21), the trachea was anastomosed by interrupted absorbable sutures. In the fibrin glue group (n = 21), the trachea was anastomosed in the same manner as the control group, with the addition of fibrin glue around the area of anastomosis. In the two groups, we studied the amount of hydroxyproline and histological findings on the seventh, 14th, and 21st postoperative day. The amount of hydroxyproline and collagen fibers in the fibrin glue group was more than in the control group on the seventh postoperative day. These results suggest that fibrin glue has a promotive effect in the healing of tracheal anastomosis. Received: August 24, 2000 / Accepted: May 15, 2001  相似文献   
79.
En bloc laminoplasty performed with threadwire saw   总被引:6,自引:0,他引:6  
OBJECTIVE: To introduce a method for a simple, nonexpansive laminoplasty that can be performed with a threadwire saw (T-saw) after en bloc laminotomy has been performed. The method can be applied along the entire spinal region, including the thoracic and lumbar spine. METHODS: An en bloc laminotomy of trapezoid shape at the cross section is performed bilaterally at the junctional area of the lamina and facet joint with a thin, flexible T-saw, while preserving the supraspinous, interspinous, and interlaminar ligaments. After the intradural procedure has been performed, the laminar flap is replaced in its original site and fixed with 1-0 nylon sutures, resulting in the complete reconstruction of the posterior supporting elements of the spinal column. RESULTS: En bloc laminoplasty was performed on 16 patients via a T-saw; most of the patients had intradural spinal tumors. The patients did not need their spinal canals to be enlarged after the intradural procedure had been performed. The follow-up period ranged from 2 to 40 months (mean +/- standard error, 22.6 +/- 3.4 mo). The laminoplasty was performed from the upper cervical to the sacral regions, although the most frequently operated level was the lower thoracic level. Two-level laminoplasty was performed in 12 patients, and three-level laminoplasty was performed in four. The laminoplasty was done safely and without any complications, except in one patient, who experienced thoracic root injury from a T-saw that was accidentally inserted anterior to the roots. No spinal column deformity or sinking of the replaced laminar flap was noted during the follow-up period; patients were assessed at follow-up via radiographs or computed tomographic scans. Computed tomographic scans obtained later indicated that bony fusion occurred at the cutting edges 1.0 to 4.0 months after surgery (mean, 1.90 +/- 0.34 mo). CONCLUSION: Simple en bloc laminoplasty performed with a T-saw is a useful, safe procedure that can be used to reconstruct the posterior spinal elements throughout the whole spinal region after the intradural procedure has been performed.  相似文献   
80.
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