全文获取类型
收费全文 | 1140461篇 |
免费 | 72985篇 |
国内免费 | 1768篇 |
专业分类
耳鼻咽喉 | 14802篇 |
儿科学 | 37410篇 |
妇产科学 | 28760篇 |
基础医学 | 181713篇 |
口腔科学 | 30520篇 |
临床医学 | 102573篇 |
内科学 | 215091篇 |
皮肤病学 | 25737篇 |
神经病学 | 79429篇 |
特种医学 | 42222篇 |
外国民族医学 | 126篇 |
外科学 | 169567篇 |
综合类 | 21626篇 |
现状与发展 | 3篇 |
一般理论 | 251篇 |
预防医学 | 83229篇 |
眼科学 | 26410篇 |
药学 | 86689篇 |
4篇 | |
中国医学 | 3244篇 |
肿瘤学 | 65808篇 |
出版年
2021年 | 8657篇 |
2018年 | 12562篇 |
2017年 | 9481篇 |
2016年 | 10733篇 |
2015年 | 11987篇 |
2014年 | 16216篇 |
2013年 | 24320篇 |
2012年 | 33551篇 |
2011年 | 35972篇 |
2010年 | 21028篇 |
2009年 | 19473篇 |
2008年 | 33157篇 |
2007年 | 36010篇 |
2006年 | 35920篇 |
2005年 | 33930篇 |
2004年 | 33034篇 |
2003年 | 31633篇 |
2002年 | 30695篇 |
2001年 | 54892篇 |
2000年 | 55784篇 |
1999年 | 46147篇 |
1998年 | 12255篇 |
1997年 | 10360篇 |
1996年 | 10649篇 |
1995年 | 10030篇 |
1994年 | 9172篇 |
1992年 | 34737篇 |
1991年 | 35351篇 |
1990年 | 34688篇 |
1989年 | 34324篇 |
1988年 | 31286篇 |
1987年 | 30663篇 |
1986年 | 28901篇 |
1985年 | 27372篇 |
1984年 | 20213篇 |
1983年 | 17182篇 |
1982年 | 9365篇 |
1979年 | 18806篇 |
1978年 | 13255篇 |
1977年 | 10941篇 |
1976年 | 10946篇 |
1975年 | 12542篇 |
1974年 | 14479篇 |
1973年 | 13940篇 |
1972年 | 13009篇 |
1971年 | 12307篇 |
1970年 | 11765篇 |
1969年 | 10880篇 |
1968年 | 10123篇 |
1967年 | 9022篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Elizabeth Campbell Ph.D. Danna Peterkin R.N. Richard Abbott M.B. B.S. John Rogers M.B. B.S. 《Preventive medicine》1997,26(6):801-807
Background.Computers that collect data from patients and provide both patients and practitioners with printed feedback on a range of health risks are a tool for assisting general practitioners with preventive care. This study assessed the impact of computer-generated printed feedback on cervical screening among women who were underscreened for cervical cancer.Method.Female attenders at two Australian general practices were randomly allocated to Experimental or Control groups. Women in both groups completed a health risk survey on a touch screen computer prior to their consultation. Those in the Experimental group received printed pages summarizing their results, including their eligibility for cervical screening and last Pap test, for themselves and their doctor. The number and proportion of underscreened women who had a Pap test in the 6 months after completing the computer survey, as determined by pathology records, were examined.Results.Of the 679 participants, 139 were classified as underscreened on the basis of self-report (74 Experimental, 65 Control) and 272 on the basis of their pathology records (148 Experimental, 124 Control). Overall about one-third of women had a test in the 6-month period, and the differences between the groups were not significant for women overall (18–70 years) or for women 18–49 years. Among women 50–70 who were underscreened based on self-report, those receiving the printout were more likely to have a Pap test in the next 6 months (P< 0.05). This pattern was also evident, but did not reach statistical significance, for older women who were underscreened based on pathology records.Conclusions.We are unable to draw conclusions regarding the effectiveness of the computer system due to the modest proportions of women screened, the small numbers, and the fact that the computer survey may have created an intervention effect in the Control group. As the study suggests the computer system is acceptable to women and may be effective for encouraging screening among older women, further exploration of the system is desirable. 相似文献
72.
J Grogan B H Nowicki T A Schmidt V M Haughton 《AJNR. American journal of neuroradiology》1997,18(7):1325
PURPOSETo study the relationship of lumbar facet joint tropism to degeneration of the cartilage and subcortical bone in the facet joints and the effect of tropism in intervertebral disk degeneration.METHODSThe orientation of 104 cadaveric lumbar facet joints with respect to sagittal plane was measured on CT scans, and the joints were classified as having no tropism, mild tropism, or severe tropism. On MR images, the severity of cartilage degeneration and bony sclerosis was measured. The correlation between tropism and degeneration was calculated, as was the relationship among age, spinal level, and degeneration.RESULTSWe identified four spinal levels with severe tropism, six with moderate tropism, and 94 without tropism. Cartilage degeneration was not significantly more severe in the joints with tropism than in the joints without. Sclerosis was slightly greater in the joints with tropism than in the joints without it. Sclerosis and cartilage degeneration were significantly related to age and spinal level.CONCLUSIONAge, spinal level, and overall facet joint angle are more important factors in facet joint degeneration than is tropism. 相似文献
73.
In this paper, the authors describe some of the complexities of collecting and presenting data on race and ethnicity based on the experiences of the Bureau of the Census. Different methods of data collection, different content and format of questions, and different definitions make it difficult to collect consistent race and ethnic data across data systems. The Bureau of the Census experiences have shown that changing ethnic self-identity and concepts, intent of the question, consistency of reporting, and the classification of persons of mixed racial parentage affect the quality of the data. These are some of the issues that must be addressed as statistical agencies and researchers seek to provide comparable race and ethnic data. 相似文献
74.
V. S. Akhunov T. V. Mirenburg X. D. Krasnopolskaya 《Journal of inherited metabolic disease》1994,17(1):104-111
Summary GM1- and GM2-gangliosides were isolated from brain and radio-labelled. The labelled moieties were localized by hydrolysis with lysosomal enzymes, followed by thin-layer chromatography of the products. High-resolution loading tests with labelled gangliosides were developed and found to differentiate infantile and juvenile forms of GM1- and GM2-gangliosidoses as well as the identification of B, O and AB types of GM2-gangliosidosis. 相似文献
75.
The effect of localized hyperthermia on blood flow and cis-diamminedichloroplatinum(II) (CDDP) pharmacokinetics in 7,12-dimethylbenz[a]anthracene-induced mammary adenocarcinomas was studied. Blood flow was determined in rat tumors and normal tissue immediately and 1, 2, and 3 h after local hyperthermia treatment (43 degrees C, 1 h) as well as in unheated tumors of rats. The rate of blood flow in the tumor was increased 1.9 times at the end of treatment relative to control values and returned to the control values by 3 h after hyperthermia. Similarly, the rate of blood flow in the peripheral skin around the tumor immediately after hyperthermia was 2.2 times greater than that of unheated skin and returned to near normal values by 3 h after heating. Tumor-bearing rats received CDDP 1 h before, at the beginning of, at the end of, and 1 h after hyperthermia administration. The CDDP plasma concentration versus time profiles for rats did not vary statistically between treatment groups. Two h after CDDP administration, the mean tumor CDDP concentration of the rats which received drug at the beginning of hyperthermia was statistically greater (P less than 0.05) than tumor CDDP concentrations in rats which received drug at the end of heat treatment. The latter group was given CDDP when tumor blood flow was the greatest; however, mean tumor drug concentration was lowest of all the groups. The mean drug concentration in tumor tissues of rats which received drug 1 h after hyperthermia was comparable to rats which received drug at the beginning of hyperthermia. This suggests that drug delivery or uptake in tumors may be altered when local hyperthermia is administered concurrently or sequentially. 相似文献
76.
C.I.V. FRANKLIN 《Journal of Medical Imaging and Radiation Oncology》1992,36(1):44-47
This paper examines the effect of patient age, tumour grade and extent of surgery on the outcome of treatment of 278 patients with high grade malignant gliomas referred to the Queensland Radium Institute between 1980 and 1987. The aim was to determine whether the extent of surgical resection alters survival rates. The extent of surgery had no effect on survival except for those patients with grade 3 tumours in whom a total excision was possible. Those in whom only a biopsy was done did not have a worse prognosis. Grading was found to be of importance, as patients with grade 3 tumours had a better survival than those with grade 4 tumours. In grade 4 tumours, those under 30 years of age had a better survival than those over 30 years, whereas with grade 3 tumours there was a gradation of age effect (under 40 years best, then 40–49 years, and those 50 years and over doing worst). 相似文献
77.
78.
79.
80.
Pankaj Hari Anand Srivastava Arun Kumar Gupta Rajendra N. Srivastava 《Pediatric nephrology (Berlin, Germany)》1997,11(4):497-498
Acute renal failure (ARF) developed in a 7-week-old infant due to bilateral candidal bezoars (fungal balls) causing obstruction
at the pelviureteric junction. The baby was born at term with an appropriate birthweight, and had been treated with broad-spectrum
antibiotics for respiratory distress and septicemia during the 1st week of life. Recovery from ARF followed renal decompression
with bilateral nephrostomy tube placement and parenteral administration of amphotericin B and 5-flucytosine.
Received August 21, 1996; received in revised form and accepted January 3, 1997 相似文献