全文获取类型
收费全文 | 1341339篇 |
免费 | 112409篇 |
国内免费 | 6376篇 |
专业分类
耳鼻咽喉 | 16721篇 |
儿科学 | 43092篇 |
妇产科学 | 36621篇 |
基础医学 | 183956篇 |
口腔科学 | 36288篇 |
临床医学 | 121118篇 |
内科学 | 278914篇 |
皮肤病学 | 31924篇 |
神经病学 | 110758篇 |
特种医学 | 55602篇 |
外国民族医学 | 274篇 |
外科学 | 210689篇 |
综合类 | 31593篇 |
现状与发展 | 2篇 |
一般理论 | 421篇 |
预防医学 | 106886篇 |
眼科学 | 28112篇 |
药学 | 93829篇 |
6篇 | |
中国医学 | 2228篇 |
肿瘤学 | 71090篇 |
出版年
2018年 | 13420篇 |
2017年 | 10667篇 |
2016年 | 12830篇 |
2015年 | 14351篇 |
2014年 | 19999篇 |
2013年 | 29819篇 |
2012年 | 36364篇 |
2011年 | 39023篇 |
2010年 | 24443篇 |
2009年 | 23975篇 |
2008年 | 36510篇 |
2007年 | 38912篇 |
2006年 | 40046篇 |
2005年 | 38624篇 |
2004年 | 36850篇 |
2003年 | 35919篇 |
2002年 | 33925篇 |
2001年 | 66121篇 |
2000年 | 68021篇 |
1999年 | 56660篇 |
1998年 | 16751篇 |
1997年 | 15048篇 |
1996年 | 16034篇 |
1995年 | 16246篇 |
1994年 | 15120篇 |
1993年 | 14170篇 |
1992年 | 47142篇 |
1991年 | 45799篇 |
1990年 | 44007篇 |
1989年 | 41862篇 |
1988年 | 38794篇 |
1987年 | 38118篇 |
1986年 | 35888篇 |
1985年 | 34661篇 |
1984年 | 26387篇 |
1983年 | 22133篇 |
1982年 | 13872篇 |
1981年 | 12460篇 |
1980年 | 11734篇 |
1979年 | 23557篇 |
1978年 | 17092篇 |
1977年 | 14398篇 |
1976年 | 13196篇 |
1975年 | 13741篇 |
1974年 | 16109篇 |
1973年 | 15417篇 |
1972年 | 14186篇 |
1971年 | 13044篇 |
1970年 | 11894篇 |
1969年 | 11112篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
901.
This paper provides a comprehensive methodological review of the literature assessing the relationship between marital satisfaction and communication. The investigations vary greatly in the adequacy of their assessment measures and soundness of their research design. Although it is generally concluded that both content and process communication are related to marital satisfaction, replication of the better designs is necessary. Specific findings and their practical implications for both future research and marital therapy are discussed. 相似文献
902.
Intrathecal morphine for post-thoracotomy pain 总被引:1,自引:0,他引:1
We wished to investigate possible differences in the duration of postoperative analgesia and the incidence of respiratory depression after the intrathecal injection in the lumbar area of 10 micrograms/kg morphine in hypobaric and hyperbaric solution for relief of post-thoracotomy pain. Twenty-nine patients received morphine plus dextrose (hyperbaric) and 21 received morphine in preservative-free normal saline. The duration of analgesia was longer with the morphine in the normal saline group than in the hyperbaric group (P less than 0.04). One patient developed delayed respiratory depression. Our data support the use of morphine in normal saline mixtures for greater duration of analgesia after thoracic operations. 相似文献
903.
Do-not-resuscitate orders for critically ill patients in the hospital. How are they used and what is their impact? 总被引:9,自引:0,他引:9
We studied compliance with do-not-resuscitate (DNR) orders at a university hospital where a DNR protocol has existed since 1979. Documentation of DNR status in patient progress notes and chart orders increased through 1983. During a 12-month period (March 1983 through April 1984), we studied in detail the medical records of 521 patients who had a cardiopulmonary arrest in the hospital. Seventy-five percent (389 of 521) of these patients were designated DNR. Patients who were designated DNR were significantly more likely to be older, to have malignancy or an abnormal mental status, and to be less likely to have acute myocardial infarction, stroke, or chronic obstructive pulmonary disease than patients in whom resuscitation was attempted. Eighty-six percent of families, but only 22% of patients, were involved in the decision to designate a patient DNR. The decision to designate a patient DNR occurred late in the course of a patient's illness, often when the patient was in coma. For 28% of patients, some form of medical care was withdrawn or withheld after they were designated DNR. These data suggest that use of the DNR protocol requires changes if patients are to participate in the decision not to undergo cardiopulmonary resuscitation. 相似文献
904.
Apramycin and gentamicin resistance in Escherichia coli and salmonellas isolated from farm animals 总被引:2,自引:0,他引:2
Since the aminoglycoside antibiotic apramycin was licensed for veterinary use in 1980, all isolates of Escherichia coli and salmonellas received at the Central Veterinary Laboratory have been monitored for resistance to apramycin and the related antibiotic gentamicin. During the period 1982-4, the incidence of resistance in E. coli to apramycin increased from 0.6% in 1982 to 2.6% in 1984. In salmonellas the incidence of resistance to apramycin increased from 0.1% in 1982 to 1.4% in 1984. Resistance to both apramycin and gentamicin was detected in six different salmonella serotypes, although an isolate of Salmonella thompson from poultry was resistant to gentamicin but not apramycin. Most of the cultures were isolated from pigs, although the incidence of apramycin resistance in S. typhimurium (DT 204C) from calves has shown a recent dramatic increase. All the isolates with one exception produced the enzyme aminoglycoside 3-N-acetyltransferase IV (ACC(3)IV). The resistance was transferable by conjugation in most of the strains examined, and the plasmids specifying the resistance have been found to belong to a number of different incompatibility groups. Plasmids from three E. coli strains were compatible with all the reference plasmids and belonged to a previously undescribed group which was investigated further. It is suggested that bacteria from humans should be examined for resistance to apramycin and gentamicin to determine the possibility of the antibiotic-resistance bacteria, and their genes, spreading from animals to humans. 相似文献
905.
906.
M M O'Kane P A King H D Edmondson 《International journal of oral and maxillofacial surgery》1986,15(4):422-424
Button wiring has been used as an alternative to eyelet wiring in the Department of Oral and Dental Surgery of Birmingham General Hospital since 1977. This clinical update reviews 65 patients with mandibular fractures in which button wires were utilised in their treatment. 相似文献
907.
J D Fortenberry R F Hill 《Journal of adolescent health care : official publication of the Society for Adolescent Medicine》1986,7(3):202-204
Incestuous child sexual abuse has received increasing attention recently, but relatively little attention has focused on the multigenerational dimensions of this problem. The case presented places incest into a multigenerational context and demonstrates how quickly family relationships may become eroticized in an uncommon form: between sisters. 相似文献
908.
Comparison of two in vitro methods of bone lead analysis and the implications for in vivo measurements 总被引:4,自引:0,他引:4
L J Somervaille D R Chettle M C Scott A C Aufderheide J E Wallgren L E Wittmers G R Rapp 《Physics in medicine and biology》1986,31(11):1267-1274
Atomic absorption spectrometry and x-ray fluorescence have been used to determine the lead content of metatarsal and tibia bone samples. For a range of bone lead levels from 6.5 to 83 micrograms g-1 of ashed bone there is no evidence of a systematic difference between the two techniques of more than 1 microgram g-1. There is, however, some evidence that random differences between the two in vitro analyses applied to the same bone sample are larger than can be accounted for by known measurement uncertainties. Variations in bone composition could account for these differences. Because the x-ray fluorescence technique is applied in an identical way to in vivo analysis, it is concluded that the uncertainties in in vivo measurements are small. 相似文献
909.
Current status of research activity in American child and adolescent psychiatry: Part I 总被引:1,自引:0,他引:1
T Shapiro D Mrazek H A Pincus 《Journal of the American Academy of Child and Adolescent Psychiatry》1991,30(3):443-448
A survey of research activity of American academic child psychiatrists was completed in February, 1989. The survey demonstrated an increase in research activity since the 1983 report in the Current Status of Child Psychiatry. A definition of a researcher was derived from a study of internists and general psychiatrists and applied to the 488 respondents (78.5% of sample), and it was found that males outnumber females and that researchers contribute significantly more to the literature and education than nonresearchers. Early research exposure and mentoring are important influences on a research career. Recommendations by researchers for future training of researchers are presented. Periodic surveys are encouraged. 相似文献
910.
D Hadley 《Rhode Island dental journal》1986,19(4):6-7, 9-10, 12-6