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   7611篇
  免费   424篇
  国内免费   31篇
耳鼻咽喉   95篇
儿科学   356篇
妇产科学   112篇
基础医学   744篇
口腔科学   110篇
临床医学   519篇
内科学   1722篇
皮肤病学   101篇
神经病学   471篇
特种医学   240篇
外科学   1257篇
综合类   173篇
一般理论   2篇
预防医学   333篇
眼科学   270篇
药学   710篇
中国医学   59篇
肿瘤学   792篇
  2023年   67篇
  2022年   118篇
  2021年   271篇
  2020年   162篇
  2019年   226篇
  2018年   268篇
  2017年   171篇
  2016年   244篇
  2015年   212篇
  2014年   326篇
  2013年   407篇
  2012年   634篇
  2011年   629篇
  2010年   386篇
  2009年   318篇
  2008年   494篇
  2007年   496篇
  2006年   388篇
  2005年   379篇
  2004年   333篇
  2003年   253篇
  2002年   212篇
  2001年   70篇
  2000年   81篇
  1999年   71篇
  1998年   51篇
  1997年   34篇
  1996年   46篇
  1995年   36篇
  1994年   29篇
  1993年   29篇
  1992年   51篇
  1991年   46篇
  1990年   40篇
  1989年   60篇
  1988年   47篇
  1987年   38篇
  1986年   33篇
  1985年   32篇
  1984年   28篇
  1983年   28篇
  1982年   16篇
  1981年   18篇
  1979年   34篇
  1978年   15篇
  1976年   14篇
  1974年   10篇
  1973年   15篇
  1972年   15篇
  1970年   10篇
排序方式: 共有8066条查询结果,搜索用时 15 毫秒
1.
2.
3.
Liposarcomas are extremely rare in the mediastinum. They may achieve considerable size before causing any symptoms. Mediastinal liposarcomas may invade surrounding structures like the pericardium or the superior vena cava. Complete surgical excision is the optimal treatment in resectable cases. Excision of adjacent structures like the pericardium may be needed if the tumor infiltrates them. We report on a case of a giant liposarcoma of the mediastinum involving both hemithoraces and extending into the neck, which was successfully managed by complete surgical excision.  相似文献   
4.
Since the first transurethral resection of the prostate (TURP) was performed by Guyon at the Necker Hospital in Paris in 1901, this treatment modality has replaced open prostatectomy as the procedure of choice for more than 95% of patients. TURP has been used in surgical treatment of benign prostatic hyperplasia (BPH) and remains the gold standard treatment. Transurethral vapor resection of the prostate (TUVRP) and holmium laser enucleation of the prostate (HoLEP) are new treatment modalities for the treatment of BPH. Each procedure has its own advantages and disadvantages. Availability of instruments, surgical expertise, and specific indications for a particular procedure are of utmost importance for successful outcome, with minimal morbidity. TURP can be either monopolar or bipolar, using thin or thick loop. Bipolar TURP is associated with less bleeding and less chances of dilutional hyponatremia. TUVRP, using a thick wedge loop, causes vaporization and resection of the prostate, and is associated with less bleeding and short operative time. HoLEP is another effective alternative for the surgical treatment of BPH. The holmium laser possesses the ideal combination of cutting and coagulation; however, it has a learning curve.  相似文献   
5.
The abdominal compartment syndrome is a life threatening condition resulting from pathologic elevation of the intraabdominal pressure. Prompt diagnosis is required to avoid significant sequelae. Diagnosis of this syndrome is based on clinical findings and intra abdominal pressure monitoring. Treatment consists of decompressive laparotomy, which corrects the pathology. Various surgical techniques are described to manage the open abdomen. Despite considerable attention accorded to this disorder, it is still associated with high morbidity and mortality. This review article deals with the identification of risk factors, pathophysiology, diagnostic criteria and treatment of critically ill patients with the abdominal compartment syndrome.  相似文献   
6.
Carcinoma gallbladder is the commonest malignancy in the Northern part of India. The heavy metals are known carcinogens while trace metals have protective effect. Aim The aim of the study is to estimate the heavy and trace metal (Lead, Zinc, Copper, Cadmium, Chromium, Manganese and Selenium) concentration in serum, bile, tissue and gallstone in patients with gallbladder diseases. Method This is a pilot study conducted in 45 cases (Group – I: 15 cases of carcinoma gallbladder, Group II: 15 patients of cholecystitis with cholelithiasis and Group – III: 15 patients of healthy control), to detect the relationship between the heavy and trace metal concentration and gall bladder carcinoma. Analysis of metal was done using Perkins‐Elmer model 2380 atomic absorption spectrophotometer. Results The serum concentration of copper and nickel was significantly high in carcinoma gallbladder patients as compared to patients with cholecystitis while zinc and selenium is low in carcinoma gallbladder patients. Bile concentration of zinc, selenium and manganese was significantly low in carcinoma gallbladder patients (p < 0.05) as compared to patients of cholelithiasis while cadmium and nickel was high. Tissue concentration of manganese was significantly low in carcinoma gallbladder patients as compared to patients of cholelithiasis while chromium was high. Gallstone concentration of copper, manganese and lead was significantly low in carcinoma gallbladder patients as compared to patients of cholelithiasis. Conclusion The heavy metals are in higher concentration in carcinoma gallbladder while trace metals are in lower concentration indicating possible role of heavy metal in gallbladder carcinogenesis.  相似文献   
7.
8.
Growing rats were exposed to 5 mg/L Pb,ad libitum in drinking water, and administered low or high doses of Mn and Cd intraperitoneal (i.p.) for 30 days. Some groups of animals were also administered combinations of Pb + Mn and Pb + Cd in an identical manner. Analysis of Pb, Mn, and Cd in tissue samples showed the expected dose-dependent accumulation when the metal was administered singly. However, combined treatment produced different types of metal shift in different tissues. Enhanced accumulation of all three metals in the brain, Mn in liver, Pb in kidney and Cd in testis and kidney after combined exposure may make target organs vulnerable to the toxic effects of metals, even when encountered at low concentrations. Further, the decreased levels of blood Pb after combined treatment with Cd or Mn suggests that the significance of blood Pb level as a diagnostic aid for Pb toxicity in coexposed conditions may not be of much value. Changes in the metallic distribution within the tissues after coexposure may be the result of a competition between the administered metals for common binding sites.  相似文献   
9.
10.
A 50 year old man with a two month history of upper abdominal pain and a one month history of anorexia and weight loss, presented with icterus and evidence of peritonitis. Laparotomy revealed biliary peritonitis which had been caused by a rupture of the fundus of the gallbladder. The common bile duct was dilated and there was a large growth in the head of the pancreas with multiple hepatic metastases. A cholecysto-jejunostomy and gastrojejunostomy were done and the patient had an uneventful recovery.  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