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   7177篇
  免费   385篇
  国内免费   29篇
耳鼻咽喉   47篇
儿科学   242篇
妇产科学   103篇
基础医学   915篇
口腔科学   125篇
临床医学   638篇
内科学   1991篇
皮肤病学   354篇
神经病学   428篇
特种医学   245篇
外科学   887篇
综合类   21篇
预防医学   279篇
眼科学   111篇
药学   447篇
中国医学   9篇
肿瘤学   749篇
  2023年   27篇
  2022年   86篇
  2021年   152篇
  2020年   101篇
  2019年   152篇
  2018年   153篇
  2017年   110篇
  2016年   136篇
  2015年   140篇
  2014年   152篇
  2013年   232篇
  2012年   370篇
  2011年   393篇
  2010年   236篇
  2009年   176篇
  2008年   327篇
  2007年   345篇
  2006年   354篇
  2005年   353篇
  2004年   329篇
  2003年   333篇
  2002年   342篇
  2001年   202篇
  2000年   195篇
  1999年   198篇
  1998年   90篇
  1997年   72篇
  1996年   73篇
  1995年   46篇
  1994年   66篇
  1993年   47篇
  1992年   142篇
  1991年   132篇
  1990年   136篇
  1989年   146篇
  1988年   106篇
  1987年   116篇
  1986年   111篇
  1985年   108篇
  1984年   84篇
  1983年   81篇
  1982年   33篇
  1980年   24篇
  1979年   52篇
  1978年   39篇
  1977年   28篇
  1976年   24篇
  1974年   38篇
  1973年   23篇
  1972年   32篇
排序方式: 共有7591条查询结果,搜索用时 15 毫秒
991.
Although a sliding tube made of plastics is very effective to keep the sigmoid colon in a straight position, there is some difficulty in handling the colonoscope, being restricted by the length of the scope. For the purpose of covering the demerits of the conventional sliding tube, a new slit sliding tube which is made up of three parts was devised by us. After straightening the sigmoidal loop, the three parts of the apparatus are joined together. Then the slit sliding tube is inserted into the descending colon with safety and ease. By using the slit sliding tube, handling of the colonoscope is scarcely restricted and becomes easy. Moreover, the slit sliding tube can be used even for the shorter scopes, by which the distal parts of the colon can be more easily examined in comparison with conventional techniques.  相似文献   
992.
Three patients underwent surgery for postmyocardial infarction ventricular septal perforation (VSP) within 3 to 21 days after onset of infarction. The hemodynamic stabilization was not obtained despite aggressive medical treatment including Intra-aortic Balloon Pumping (IABP) in one patient. The others had sudden hemodynamic deterioration during IABP support. In two of the three cases, the VSP were closed via transinfarct ventriculotomy with double Dacron patch, and ventricular wall reconstruction was performed to sandwich the double septal patch between ventricular free walls with Dacron felt strips. Two of the three patients survived. Our experience suggests that early surgical intervention is essential unless medical therapy results in clinical improvement and the double patch method may provide a successful operative repair and comeout.  相似文献   
993.
Captafol was administered at dietary levels of 0 (control), 750 and 1,500 parts per million (ppm) to groups of 50 male and 50 female F344/DuCrj rats for 104 weeks, and then all animals were maintained without captafol for a further 8 weeks, and killed in week 113. Renal cell carcinoma was found in eight of 50 male rats treated with 1,500 ppm and in one of 50 male rats treated with 750 ppm of captafol. The incidences of renal adenomas, including micro-adenomas, and basophilic altered cell tubules were significantly higher in both sexes treated with captafol than in controls, and the increases were apparently dose-dependent except that of adenomas in females. The incidences of neoplastic and preneoplastic lesions of the kidney in captafol-treated animals were higher in males than in females. Captafol also induced hepatocellular carcinomas in four of 50 female rats in the 1,500 ppm group. The incidences of hyperplastic (neoplastic) nodules and foci of cellular alterations in the liver were also significantly increased in both sexes treated with captafol, the increases being dose-dependent. In conclusion, captafol induced renal cell carcinomas in male rats and hepatocellular carcinomas in female rats.  相似文献   
994.
995.
The anti-tumor effect of twice a week instillation of 30 mg mitomycin C combined with 200 mg cytosine arabinoside dissolved in 30 ml saline was studied in 37 bladder tumor patients. Endoscopic or histological disappearance of the tumor was observed in 19 cases, average instillation being 16.4 times. Small (less than 1 cm in diameter), low grade, low stage and villous-surfaced tumors were more sensitive to this therapy. Further more, in the cases showing a complete response, frequency of the intravesical tumor recurrence significantly decreased compared with the cases showing no response. The clinical results of this therapy are compared mainly with those of TUR performed at our hospital, and the usefulness and clinical limitation of this kind of management in the treatment of bladder tumors are discussed.  相似文献   
996.
A 63-year-old male was admitted with a complaint of right abdominal mass. A right renal tumor associated with direct invasion to liver and with lobulated cystic lesion and renal solitary cyst were diagnosed preoperatively by aortography and computed tomography. Transperitoneal radical nephrectomy and partial resection of liver metastasis were performed. Histological diagnosis was clear cell carcinoma with dilated tubuli. Tumor invasion to the inferolateral portion of the liver and to the renal solitary cyst wall were demonstrated by both gross and microscopic examinations. The coexistence of tumor and cyst in the same kidney is rare. Our case probably had both the type I and II or III tumors according to Gibson classification. Twenty months after radical nephrectomy, pulmonary metastases were detected by chest x-ray, tomography and bronchial arteriography. All metastatic lesions were replaced by fibrous change 7 months after the four bronchial arterial infusions (BAI) of ADM 30 mg and irradiation with a dose of 5,000 rads to each lesion. After 9 tumor-free months, recurrence of pulmonary metastases were pointed out by chest x-ray and tomography. They (four coin lesions) were treated with anticancer therapy, mainly irradiation and twice insufficient BAI. Three of them were occupied entirely by fibrous change and another solid one remained in the right pulmonary apex without enlargement for the past 4 months. Radical nephrectomy and partial resection of the liver for the primary renal cell carcinoma with direct invasion to liver, BAI and irradiation for the two pulmonary metastases have kept the patient alive for 4 years.  相似文献   
997.
The kinetics of high density lipoprotein apoprotein A-I were determined in three subjects with severe alcoholic hepatitis. Lipoprotein was obtained from three healthy subjects, radioiodinated, and injected into the patients and the donors. The catabolic rate of A-I was two to four times higher in the patients compared to a group of 18 control subjects studied previously. In the patients only, about 20% of the radiolabeled apoproteins rapidly appeared in the lipoprotein-poor fraction of plasma, which also contained substantial amounts of unlabeled A-I. The findings show that the reduced concentration of A-I in alcoholic hepatitis (less than half-normal), is due not to diminished synthesis (synthesis was normal) but to rapid degradation. This may reflect disruption of abnormal high density lipoproteins due to lack of cofactors.  相似文献   
998.
The statistics of urological operations performed at our department between Jan., 1, 1982 and Dec., 31, 1986 were reviewed. During the 5 year period, 2331 patients were admitted to our hospital and 2192 urological operations were performed on 1834 patients. These statistics were compared with earlier statistics for two periods (1972-1976 and 1977-1981) and the recent trend of urological operations was investigated. With regard to operated organ, operations on the kidney were the most frequent followed by those on the urinary bladder. Operations on the ureter decreased during the recent 5 year period and they were the fourth most frequent following those on the scrotum, scrotal contents and penis. Operations on the adrenal gland, retroperitoneal space and parathyroid gland have gradually increased. As in the former report, transurethral resection of bladder tumor (TUR-Bt) was the most frequent and nephrectomy, TUR of prostate (TUR-P) and renal allotransplantation have followed. TUR-Bt and TUR-P have increased more and more and due to the introduction of percutaneous nephrolithotripsy and transureteral lithotripsy, open surgery for urolithiasis has greatly decreased. Endourological operations will still be on the increase.  相似文献   
999.
1000.
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