全文获取类型
收费全文 | 1613270篇 |
免费 | 132314篇 |
国内免费 | 2601篇 |
专业分类
耳鼻咽喉 | 21703篇 |
儿科学 | 53416篇 |
妇产科学 | 46675篇 |
基础医学 | 229085篇 |
口腔科学 | 47335篇 |
临床医学 | 142936篇 |
内科学 | 316590篇 |
皮肤病学 | 34231篇 |
神经病学 | 131102篇 |
特种医学 | 64931篇 |
外国民族医学 | 474篇 |
外科学 | 244743篇 |
综合类 | 39981篇 |
现状与发展 | 3篇 |
一般理论 | 568篇 |
预防医学 | 124887篇 |
眼科学 | 36625篇 |
药学 | 122025篇 |
4篇 | |
中国医学 | 2994篇 |
肿瘤学 | 87877篇 |
出版年
2018年 | 15169篇 |
2016年 | 13210篇 |
2015年 | 15350篇 |
2014年 | 21084篇 |
2013年 | 31952篇 |
2012年 | 43510篇 |
2011年 | 45754篇 |
2010年 | 26821篇 |
2009年 | 25732篇 |
2008年 | 43795篇 |
2007年 | 46081篇 |
2006年 | 46842篇 |
2005年 | 45417篇 |
2004年 | 44811篇 |
2003年 | 42815篇 |
2002年 | 41854篇 |
2001年 | 75797篇 |
2000年 | 78383篇 |
1999年 | 66476篇 |
1998年 | 17836篇 |
1997年 | 16394篇 |
1996年 | 16373篇 |
1995年 | 16078篇 |
1994年 | 15126篇 |
1993年 | 14268篇 |
1992年 | 55474篇 |
1991年 | 53802篇 |
1990年 | 52584篇 |
1989年 | 50853篇 |
1988年 | 47241篇 |
1987年 | 46586篇 |
1986年 | 44311篇 |
1985年 | 42859篇 |
1984年 | 32043篇 |
1983年 | 27582篇 |
1982年 | 16162篇 |
1981年 | 14457篇 |
1980年 | 13569篇 |
1979年 | 30469篇 |
1978年 | 21068篇 |
1977年 | 17765篇 |
1976年 | 16695篇 |
1975年 | 17576篇 |
1974年 | 21492篇 |
1973年 | 20677篇 |
1972年 | 18857篇 |
1971年 | 17773篇 |
1970年 | 16289篇 |
1969年 | 15273篇 |
1968年 | 13955篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
Deep-frozen cancellous allografts have been used to restore the proximal femur of 23 hips following failed total hip arthroplasty. The canal is cleared and reaming is performed under direct vision through a cortical window. A modified Huckstep prosthesis permits early weight-bearing on the distal femur regardless of the state of proximal bone, but retains the option for later restoration of proximal loading once grafts appear mature. This transfer has been performed on four occasions. All 23 patients have had relief of pain with early ambulation. The follow-up periods ranged from six to 30 months. With the exception of one deep infection, the grafts have not undergone resorption in this period of follow-up study. Consolidation appears slower when the defect has followed multiple operations than following an initial revision for prosthetic loosening. The basic bone bank facilities are required for the supply of frozen allografts. 相似文献
972.
973.
974.
975.
Malignant islet cell tumors are commonly treated with surgical resection. Chemotherapy is reserved for residual, unresectable, or metastatic disease. The role for radiotherapy has not been clearly defined. This article describes three cases of advanced islet cell tumors treated effectively with radiotherapy. This experience, in addition to that from other published reports, suggests that radiotherapy is a useful mode for treating advanced islet cell carcinoma. 相似文献
976.
Unemployment causes ill health: the wrong track 总被引:1,自引:0,他引:1
A R Kagan 《Social science & medicine (1982)》1987,25(2):217-218
It is not unemployment per se that causes ill health. It can be a very desirable state. There are no diseases specific to unemployment. Contrast this with employment. Unemployment shares with all other socio-environmental situations risk of exposure to common physical, social and psychological stressors that predispose to disease. Focus for action and research should be on reducing such stressors and not on provision of full employment. The former is likely to be possible and beneficial. The latter is likely to be impossible and carries a risk of making matters worse. As an immediate first step, that will reduce 'cratogenic' disease, people in authority should stop misleading the public into believing that unemployment is the cause of ill health. 相似文献
977.
Continuous mixed venous oximetry in critically ill surgical patients. 'High-tech' cost-effectiveness 总被引:2,自引:0,他引:2
R Orlando 《Archives of surgery (Chicago, Ill. : 1960)》1986,121(4):470-471
Mixed venous oxygen saturation (Svo2) provides a measure of cardiorespiratory ability to meet the body's needs for oxygen. The Svo2 was measured continuously in 20 critically ill surgical patients using a pulmonary-artery oximetry system. The accuracy of the technique was validated by comparing initial continuous Svo2 to the laboratory determination of Svo2. Oximetry was used to guide therapeutic decisions regarding fluid, inotropic agents, vasodilators and ventilator setting and was useful in ten cases. Sepsis developed in nine patients; this severely limited the usefulness of the technique. With clinical decision making based on oximetry, there was a savings per catheter of 2.65 cardiac output determinations and 5.9 venous blood gas determinations, resulting in a net savings per catheter of +75. 相似文献
978.
Curative local excision of rectal adenocarcinoma 总被引:3,自引:0,他引:3
The records of all 28 patients with rectal adenocarcinoma treated by potentially curative local excision by one surgeon (A.M.C.) between 1970 and 1984 were reviewed. Patient age, sex, tumour size, site, degree of differentiation and level of invasion are reported. The procedure was associated with no mortality and minimal morbidity. Twenty-two patients, followed for an average of 51 months, have either died of other causes or remain free of recurrent or disseminated malignancy. Six patients have required further surgery for local recurrence. Of these, one patient has had a repeat local excision while the remaining five patients have had an abdominoperineal excision of the rectum. All six patients, followed since the second operation for an average of 50 months, are free of further recurrent or disseminated disease. The results reported in this review suggest that in a selected group of patients with rectal adenocarcinoma curative local excision may offer a safe alternative to more radical forms of surgery. 相似文献
979.
Delta hepatitis virus infection in China 总被引:1,自引:0,他引:1
D Q Wang H H Cheng G Y Minuk L H Liu C M Anand T C Stowe H X Wang D C Ying Y R Tu K A Buchan 《International journal of epidemiology》1987,16(1):79-83
To assess the prevalence, epidemiological features and prognostic implications of hepatitis D (Delta) in Sichuan Province, The People's Republic of China, 649 sera (515 from HBsAg positive patients and 134 from HBsAg negative subjects) were tested by radioimmunoassay (RIA) for antibody to the hepatitis D virus (anti-HD). Forty-seven sera (7.2%) showed some degree of reactivity. Serial dilutions of these sera indicated that prozoning was not responsible for the equivocal results. Thirty-four of the 47 sera were submitted under code to a second laboratory for independent analysis. According to those results anti-HD antibodies were detected in four of these sera. The overall prevalence of anti-HD in the HBsAg positive patients therefore was 0.8% (4/515). On the basis of clinical, biochemical and histological data 427 HBsAg positive sera were further divided into acute Type B hepatitis, chronic Type B hepatitis, healthy carrier state and hepatocellular carcinoma (HCC) subgroups. Two of 65 (3.1%) anti-HD positive sera belonged to the acute Type B hepatitis group; one of 104 (0.9%), the chronic Type B hepatitis group and one of 246 (0.4%), the healthy carrier group. No antibody was detected in sera from 12 HBsAg positive HCC patients. All HBsAg negative patients were negative for anti-HD antibody. The results of this study indicate that despite a high prevalence of hepatitis B virus infection, positive serology for delta virus is uncommon in Sichuan Province, The People's Republic of China. 相似文献
980.
The influence of different levels of dietary fat on the incidence and growth of MNU-induced mammary carcinoma in rats 总被引:1,自引:0,他引:1
This study describes the influence of isocalorically fed diets (containing different amounts of fat) on tumor incidence and parameters of fat metabolism in female Sprague-Dawley rats. Comparisons are made between rats induced with methylnitrosourea (25 mg/kg body wt) and untreated controls (Group I). The animals received either control diets (3.9% fat by weight, Groups I and II) or fat-enriched diets (10.7%, Group III; 15.6%, Group IV; 21.4%, Group V) over a period of 180 days. At the termination of the experiment, intake of the diet containing 10.7% fat by weight (24% fat per total calories) was associated with the highest tumor incidence. Comparing the different diets, liver lipid concentrations in the individual groups increased with increasing dietary fat, whereas the total lipid in plasma decreased. During the feeding period, total lipid of the liver and plasma, and plasma cholesterol, increased in all groups, but triglycerides of plasma decreased. However, when plasma cholesterol and triglycerides were calculated as a relative amount of total lipid in plasma, cholesterol was found to be significantly decreased in Groups III and IV, and triglycerides were increased in Group III but decreased significantly in Groups I, II, and V at the end of the experiment. 相似文献