全文获取类型
收费全文 | 9964篇 |
免费 | 880篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 74篇 |
儿科学 | 341篇 |
妇产科学 | 289篇 |
基础医学 | 1348篇 |
口腔科学 | 162篇 |
临床医学 | 1342篇 |
内科学 | 1847篇 |
皮肤病学 | 189篇 |
神经病学 | 956篇 |
特种医学 | 253篇 |
外科学 | 980篇 |
综合类 | 120篇 |
一般理论 | 16篇 |
预防医学 | 1292篇 |
眼科学 | 162篇 |
药学 | 732篇 |
中国医学 | 13篇 |
肿瘤学 | 749篇 |
出版年
2023年 | 120篇 |
2022年 | 138篇 |
2021年 | 242篇 |
2020年 | 220篇 |
2019年 | 271篇 |
2018年 | 288篇 |
2017年 | 236篇 |
2016年 | 282篇 |
2015年 | 290篇 |
2014年 | 347篇 |
2013年 | 532篇 |
2012年 | 758篇 |
2011年 | 799篇 |
2010年 | 397篇 |
2009年 | 332篇 |
2008年 | 637篇 |
2007年 | 616篇 |
2006年 | 604篇 |
2005年 | 560篇 |
2004年 | 434篇 |
2003年 | 467篇 |
2002年 | 410篇 |
2001年 | 114篇 |
2000年 | 111篇 |
1999年 | 115篇 |
1998年 | 87篇 |
1997年 | 58篇 |
1996年 | 66篇 |
1995年 | 48篇 |
1994年 | 60篇 |
1993年 | 46篇 |
1992年 | 72篇 |
1991年 | 59篇 |
1990年 | 75篇 |
1989年 | 67篇 |
1988年 | 63篇 |
1987年 | 56篇 |
1986年 | 56篇 |
1985年 | 34篇 |
1984年 | 36篇 |
1983年 | 52篇 |
1982年 | 36篇 |
1981年 | 32篇 |
1979年 | 39篇 |
1978年 | 33篇 |
1977年 | 31篇 |
1975年 | 30篇 |
1974年 | 34篇 |
1973年 | 45篇 |
1972年 | 31篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
21.
This paper reports the prevalence of chronic esophagitis and nutritional status among 538 young persons aged 15 to 26 years from the high risk area for esophageal cancer. Of these subjects, 166 were from households with history of esophageal cancer and 372 were from households without history of esophageal cancer. The Incidences of chronic esophagltis among male and female adolescents were 37. 6% and 36% respectively, which was significantly higher than those in the low risk area (17%). The frequency of chronic esophagltis in the adolescents in the households with history of esophageal cancer was aiso higher than in those In the households without history of esophageal cancer. The deficiencies of vitamins, especially of riboflavin and ascorbate, are prevalent and severe among these adolescents. Ascorbate deficiency Is correlated with the severity of the chronic esophagltis. These results indicate that chronic esophagltis may be involved in the natural history of esophageal carclnogenesis. Nutrient defic 相似文献
22.
23.
24.
Abstract: The development of a teaching package for nurse educators on drug and alcohol problems is described and the contents of its 16 modules outlined. 相似文献
25.
M Ingram S Jacques D B Freshwater G B Techy C H Shelden J T Helsper 《Archives of surgery (Chicago, Ill. : 1960)》1987,122(12):1483-1486
We present the preliminary results of a phase I trial of adoptive immunotherapy for recurrent or residual malignant glioma. The protocol is based on surgical debulking followed by implantation into the tumor bed of autologous lymphocytes that have been stimulated with phytohemagglutinin-P and then cultured in vitro in the presence of interleukin 2. Fifty-five patients with a mean Karnofsky rating of 64 were treated between February 1985 and March 1987. No significant toxicity was associated with the immunotherapy. Fifty patients had a positive initial response to therapy, nine patients had early recurrence (two to four months after treatment), and 22 patients died. We comment on major differences between the protocol described and other immunotherapy protocols. 相似文献
26.
OBJECTIVE--To examine trends (1979 through 1989) and current status in firearm and nonfirearm homicide rates by level of urbanization among persons 15 through 19 years of age. DESIGN--The Compressed Mortality File, a county-level mortality and population database maintained by the National Center for Health Statistics, Centers for Disease Control, Hyattsville, Md, and the 1980 Human Resource Profile County Codes are used to analyze age-, sex-, and race-specific firearm and nonfirearm homicide rates by urbanization level. SETTING--United States, 1979 through 1989. SUBJECTS--Black and white males and females 15 through 19 years of age whose underlying cause of death was either firearm homicide (E965.0 through E965.4 or E970) or nonfirearm homicide (E960 through E964, E965.5 through E969, or E971 through E978) in the ICD-9 (International Statistical Classification of Diseases, Injuries, and Causes of Death, Ninth Revision). MAIN OUTCOME MEASURES--Urbanization level-specific firearm and nonfirearm homicide rates. RESULTS--The 1989 firearm homicide rate in metropolitan counties was nearly five times the rate in nonmetropolitan counties (13.7 vs 2.9 deaths per 100,000 population). Firearm homicide rates were highest in core metropolitan counties, 27.7 per 100,000 population; rates were higher for black males than for any other race-sex group in each of five county urbanization strata for 1979 through 1989. Nonfirearm homicide rates are considerably lower, with smaller urban differentials; the rate in metropolitan counties was 1.4 times the rate in nonmetropolitan counties (2.6 vs 1.8 per 100,000 population). From 1979 through 1984, firearm homicide rates declined in each of the county strata. From 1984 through 1987, firearm homicide rates increased, and from 1987 through 1989 they increased rapidly, from 23% to 35% per year in the four metropolitan strata. From 1979 through 1989, nonfirearm homicide rates declined or remained stable. CONCLUSIONS--Large urbanization differentials in firearm homicide and smaller differentials in nonfirearm homicide are identified. Firearm homicide rates are highest and increasing the fastest among black teenage males in the core, fringe, and medium metropolitan strata. 相似文献
27.
28.
29.
Zvi Laron Jenny Frenkel lrit Gil-Ad Beatrice Klinger Ernesto Lubin Patrick Wuthrich François Boutignon Vincent Lengerts Romano Deghenghi 《Clinical endocrinology》1994,41(4):539-541
OBJECTIVE Hexarelin is a new synthetic growth hormone releasing peptide. We have tested the efficacy of intranasal (i.n.) administration of hexarelin to stimulate plasma GH and have compared this to the intravenous (i.v.) administration of the peptide. PATIENTS Ten children with familial short stature (FSS) aged 5·5-15·5 years and two known GH deficient patients aged 24 and 28 years without GH treatment. METHODS All 12 subjects were submitted to i.v. (1 μg/kg) and i.n. (20 μg/kg) hexarelin tests with a one-week interval between tests. Blood samples for GH, TSH, fT4 and T3 were obtained at 0, 15, 30, 60, 90 and 120 minutes. The hormone determinations were made by standard radio-immunoassays (RIA). RESULTS Both the i.n. and i.v. administration of hexarelin induced a large GH response, the mean (±SD) being 72·2± 35·5 mU/l for the i.n. test and 79·6 ± 53·0 mU/l for the i.v. test. The peak GH in the i.v. test occurred at 15–30 minutes and in the i.n. test between 30 and 60 minutes. The GH deficient patients showed no GH response In either test. Plasma TSH decreased in the FSS children from a mean (±SD) of 1.0 ± 0·26 to 0·64±0 2 mU/l (P<0 005) during the i.n. test and from 1·0±0·3 to 0·7±0·3mU/l (P> 0 05) during the I.v. test. In the isolated GH deficient patient, plasma TSH decreased from 1·06±0·38 mU/l to 0·86±0·17 during the i.v. test and from 1·60±0·01 to 1·11±0·06mU/l during the i.n. test. There were no significant changes in plasma fT4 or T3 in any of the tests. CONCLUSIONS The synthetic hexapeptide hexarelin is a potent pituitary GH stimulator when administered intra-nasally. The GH response was similar to that observed after intravenous hexarelin. Simultaneously, there was a significant decrease in plasma TSH but the concentrations remained in the normal range. These findings appear to be of theoretical and practical relevance to the investigation and management of short children. 相似文献
30.
Jenny Weinstein BPhil BA Msc 《Health expectations》2006,9(2):98-109
OBJECTIVE: This study compares the process and outcomes of two approaches to engaging mental health (MH) service users in the quality assurance (QA) process. BACKGROUND: QA plays a significant role in health and care services, including those delivered in the voluntary sector. The importance of actively, rather than passively, involving service users in evaluation and service development has been increasingly recognized during the last decade. DESIGN: This retrospective small-scale study uses document analysis to compare two QA reviews of a MH Day Centre, one that took place in 1998 as a traditional inspection-type event and one that took place in 2000 as a collaborative process with a user-led QA agenda. Setting and participants The project was undertaken with staff, volunteers and service users in a voluntary sector MH Day Centre. Intervention The study compares the management, style, evaluation tools and service user responses for the two reviews; it considers staff perspectives and discusses the implications of a collaborative, user-led QA process for service development. RESULTS: The first traditional top-down inspection-type QA event had less ownership from service users and staff and served the main purpose of demonstrating that services met organizational standards. The second review, undertaken collaboratively with a user-led agenda focused on different priorities, evolving a new approach to seeking users' views and achieving a higher response rate. CONCLUSIONS: Because both users and staff had participated in most aspects of the second review they were more willing to work together and action plan to improve the service. It is suggested that the process contributed to an evolving ethos of more effective quality improvement and user involvement within the organization. 相似文献