全文获取类型
收费全文 | 4240篇 |
免费 | 585篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 31篇 |
儿科学 | 178篇 |
妇产科学 | 66篇 |
基础医学 | 572篇 |
口腔科学 | 117篇 |
临床医学 | 479篇 |
内科学 | 1019篇 |
皮肤病学 | 73篇 |
神经病学 | 583篇 |
特种医学 | 165篇 |
外科学 | 542篇 |
综合类 | 11篇 |
预防医学 | 352篇 |
眼科学 | 119篇 |
药学 | 188篇 |
中国医学 | 5篇 |
肿瘤学 | 348篇 |
出版年
2024年 | 8篇 |
2023年 | 66篇 |
2022年 | 68篇 |
2021年 | 120篇 |
2020年 | 128篇 |
2019年 | 102篇 |
2018年 | 170篇 |
2017年 | 177篇 |
2016年 | 169篇 |
2015年 | 185篇 |
2014年 | 215篇 |
2013年 | 300篇 |
2012年 | 268篇 |
2011年 | 265篇 |
2010年 | 197篇 |
2009年 | 263篇 |
2008年 | 238篇 |
2007年 | 239篇 |
2006年 | 219篇 |
2005年 | 217篇 |
2004年 | 184篇 |
2003年 | 153篇 |
2002年 | 169篇 |
2001年 | 56篇 |
2000年 | 42篇 |
1999年 | 52篇 |
1998年 | 64篇 |
1997年 | 63篇 |
1996年 | 62篇 |
1995年 | 47篇 |
1994年 | 37篇 |
1993年 | 36篇 |
1992年 | 40篇 |
1991年 | 27篇 |
1990年 | 9篇 |
1989年 | 22篇 |
1988年 | 10篇 |
1987年 | 18篇 |
1986年 | 14篇 |
1985年 | 16篇 |
1984年 | 15篇 |
1983年 | 12篇 |
1982年 | 9篇 |
1981年 | 9篇 |
1978年 | 6篇 |
1977年 | 8篇 |
1975年 | 7篇 |
1974年 | 6篇 |
1973年 | 6篇 |
1971年 | 6篇 |
排序方式: 共有4848条查询结果,搜索用时 46 毫秒
991.
992.
993.
Xianzheng Zhou Frank Momburgu Tianmin Liuu Ussama M. Abdel Motalu Mikael Jondalu Günter J. Hmmerlingu Hans-Gustaf Ljunggren 《European journal of immunology》1994,24(8):1863-1868
In the class II region of the major histocompatibility complex (MHC), four genes implicated in MHC class I-mediated antigen processing have been described. Two genes (TAP 1 and TAP 2) code for multimembrane-spanning ATP-binding transporter proteins and two genes (LMP 2 and LMP 7) code for subunits of the proteasome. While TAP 1 and TAP 2 have been shown to transport antigenic peptides from the cytosol into the endoplasmic reticulum, where the peptides associate with MHC class I molecules, the role of LMP 2/7 in antigen presentation is less clear. Using antigen processing mutant T2 cells that lack TAP 1/2 and LMP 2/7 genes, it was recently shown that expression of TAP 1/2 alone was sufficient for processing and presentation of the influenza matrix protein M1 as well as the minor histocompatibility antigen HA-2 by HLA-A2. To understand if presentation of a broader range of viral antigens occurs in the absence of LMP 2/7, we transfected T2 cells with TAP 1, TAP 2 and either of the H-2Kb, Db or Kd genes and tested their ability to present vesicular stomatitis vires and influenza virus antigens to virus-specific cytotoxic T lymphocytes. We found that T2 cells, expressing TAP 1/2 gene products, presented all tested viral antigens restricted through either the H-2Kb, Db or Kd class I molecules. We conclude that the proteasome subunits LMP 2/7 as well as other gene products in the MHC class II region, except from TAP 1/2, are not generally necessary for presentation of a broader panel of viral antigens to cytotoxic T cells. However, the present results do not exclude that LMP 2/7 in a more subtle way may, or in rare cases completely, affect processing of antigen for presentation by MHC class I molecules. 相似文献
994.
Multi-locus analysis of HLA class II genes in DR2-positive IDDM haplotypes in Finland 总被引:1,自引:0,他引:1
Helena Reijonen Jorma Ilonen Hans K. Åkerblom Mikael Knip Hans-Michael Dosch "Childhood Diabetes in Finland" Study Group 《Tissue antigens》1994,43(1):1-6
Abstract: In this study we characterized the haplotypes found in IDDM patients that normally confer resistance to the disease in order to localize the polymorphisms relevant for the protection. We studied 15 DR2-positive subjects with IDDM for their DRB1, DRB5 and DQB1 genes using RFLP, polymerase chain reaction (PCR), oligonucleotide typing, and in some specific cases direct sequencing after allele-specific PCR. In addition we analyzed 39 DR2-positive, IDDM non-associated haplotypes representing those haplotypes that are not inherited to probands and hence are present only in healthy family members. The frequency of the DRB1*1501-DRB5*0101-DQB1*0602 haplotype was slightly decreased among diabetic patients (80% vs. 92%). In addition, two unconventional haplotypes DRB1*1501-DRB5*0101-DQB1*05031 and DRB1*1501-DRB5*0101-DQB1*0502 were found in patients with IDDM while all the control ones were conventional. The sequencing of the DQB1*0602 allele present in IDDM haplotypes showed no differences when compared to the controls. These results support the primary but not absolute role of DQ in the protection against IDDM. An additional role of factors centromeric to DQB1 gene was suggested by findings based on the biallelic TaqI RFLP polymorphism of the DQA2 gene. All DR2-DQB1*0602 IDDM haplotypes were associated with the 2.1-kb fragment while in the control group the 2.1-kb and 1.9-kb fragments were evenly distributed. 相似文献
995.
Kee Thai Yeo Ju Lee Oei Daniele De Luca Georg M. Schmölzer Robert Guaran Pamela Palasanthiran Kishore Kumar Giuseppe Buonocore Jeanie Cheong Louise S. Owen Satoshi Kusuda Jennifer James Gina Lim Ankur Sharma Sabita Uthaya Christopher Gale Elizabeth Whittaker Cheryl Battersby Neena Modi Mikael Norman Lars Naver Eric Giannoni Yenge Diambomba Prakeshkumar S. Shah Luigi Gagliardi Michael Harrison Shakti Pillay Abdullah Alburaey Yuan Yuan Huayan Zhang 《Acta paediatrica (Oslo, Norway : 1992)》2020,109(11):2192-2207
996.
Background: The Swedish adjustable gastric band (SAGB) was introduced in 1985 and rapidly gained popularity.Today more than
21,000 gastric banding procedures have been performed in Europe. The reported results of gastric banding operations are mainly
good, although the method is not without controversies and risks. We report here our initial experience with the SAGB. Methods:
60 patients (44 women, 16 men) were treated surgically for morbid obesity between the years 1996 and 1999, with SAGB. Median
age of the patients was 44 years (range 21-64) and preoperative median Body Mass Index (BMI, kg/m2) was 45 (range 35-55).
3 patients were operated by an open approach, and the remaining 57 laparoscopically. Results:Operative time was 62-206 minutes
(median 97 minutes). Only one operation was converted to open approach (1.8%), due to extensive adhesions. No intraoperative
complications occurred. At 1 year follow-up, mean weight loss was 30 kg, mean excess weight loss was 50%, and median BMI was
35. 4 patients have been reoperated so far (6.7%) due to slippage of the band (2 patients), infection of the band (1 patient),
and leaking of the filling system (1 patient). Median postoperative hospital stay was 3 days (range 2-53). Mortality was 0%.
Immediate postoperative mor- bidity-rate was 12% (7/60), although serious morbidity occurred in only 1 patient (1.7%). Conclusions:
Laparoscopically placed adjustable gastric band is a good option for the morbidly obese patient. 相似文献
997.
Cholecystectomy: costs and health-related quality of life: a comparison of two techniques. 总被引:3,自引:0,他引:3
Erik Nilsson Axel Ros Mikael Rahmqvist Karin B?ckman Per Carlsson 《International journal for quality in health care》2004,16(6):473-482
BACKGROUND: Outcomes of previous health economic evaluations comparing minilaparotomy cholecystectomy and laparoscopic cholecystectomy have been inconsistent. OBJECTIVE: To compare costs for minilaparotomy cholecystectomy and laparoscopic cholecystectomy and to study changes in quality of life induced by these operations. DESIGN: Single-blind, randomized controlled trial, run from 1 March 1997 to 30 April 1999. SETTING: One university hospital and four non-university hospitals in Sweden. MAIN MEASURE: : Cost and perceived health estimation according to the global quality of life instrument EuroQol-5D. RESULTS: Of 1719 cholecystectomy patients at five centres, 724 entered the trial and were treated with minilaparotomy cholecystectomy or laparoscopic cholecystectomy, 362 in each group. Total health care costs were less for minilaparotomy cholecystectomy than for laparoscopic cholecystectomy (median values US$2428 for minilaparotomy cholecystectomy versus US$2613 or US$3006 for laparoscopic cholecystectomy with 100 operations per year and reusable trocars or 50 operations per year and disposable trocars, respectively). There was no significant difference in total costs (including costs due to loss of production) between minilaparotomy cholecystectomy and laparoscopic cholecystectomy with 100 operations per year and reusable trocars in laparoscopic cholecystectomy (US$3731 versus US$3649, respectively). However, in calculations assuming 50 operations per year and disposable trocars in laparoscopic cholecystectomy, this technique was more expensive than minilaparotomy cholecystectomy (US$4042 versus US$3731). Health-related quality of life was slightly but significantly lower for the minilaparotomy cholecystectomy group 1 week after surgery. One month and 1 year postoperatively no difference between the randomized groups was found. CONCLUSION: Total costs did not differ between minilaparotomy cholecystectomy and laparoscopic cholecystectomy with high-volume surgery and disposable trocars, whereas laparoscopic cholecystectomy was more expensive with fewer operations and disposable trocars. The gain in health-related quality of life with laparoscopic cholecystectomy compared with minilaparotomy cholecystectomy was small and of limited duration. 相似文献
998.
OBJECTIVES: Portfolio theory has been suggested as a means to improve the risk-return characteristics of investments in health-care programs through diversification when costs and effects are uncertain. This approach is based on the assumption that the investment proportions are not subject to uncertainty and that the budget can be invested in toto in health-care programs. METHODS: In the present paper we develop an algorithm that accounts for the fact that investment proportions in health-care programs may be uncertain (due to the uncertainty associated with costs) and limited (due to the size of the programs). The initial budget allocation across programs may therefore be revised at the end of the investment period to cover the extra costs of some programs with the leftover budget of other programs in the portfolio. RESULTS: Once the total budget is equivalent to or exceeds the expected costs of the programs in the portfolio, the initial budget allocation policy does not impact the risk-return characteristics of the combined portfolio, i.e., there is no benefit from diversification anymore. CONCLUSION: The applicability of portfolio methods to improve the risk-return characteristics of investments in health care is limited to situations where the available budget is much smaller than the expected costs of the programs to be funded. 相似文献
999.
1000.
Tina R. Kilburn Merete Juul Sørensen Mikael Thastum Ronald M. Rapee Charlotte Ulrikka Rask Kristian Bech Arendt 《Nordic journal of psychiatry》2013,67(4-5):273-280
AbstractPurpose: Autism spectrum disorder (ASD) includes core symptoms that affect general and social development. High risk of developing comorbid disorders such as anxiety is prominent. Up to 60% of children with ASD suffer from anxiety disorders which can negatively influence educational, social and general development together with quality of life. This study is the first to investigate the feasibility of the manualised cognitive behavioural therapy (CBT) group programme 'Cool Kids ASD' for anxiety adapted for children with ASD in a general hospital setting.Methods: Nine children, aged 9–13 years, with ASD and anxiety recruited from a public child psychiatric health clinic were enrolled in the study. Outcome measures were collected from both child and parent pre- and post-treatment and at 3-month follow-up and included scores from a semi-structured anxiety interview, together with questionnaires on anxiety symptoms, life interference, children's automatic thoughts and satisfaction with the programme.Results: Eight out of nine families found the programme useful and would recommend it to other families in a similar situation. Six families attended all 12 sessions in the programme, two missed one session and one family only managed to attend eight sessions. At follow-up, five children were free of all anxiety diagnoses and a further two out of the nine children no longer met the criteria for their primary anxiety diagnosis.Conclusions: This study suggests that the transition of the group programme 'Cool Kids ASD' from University Clinics to standard child psychiatric clinical settings is feasible. Further randomised studies are needed to confirm the efficacy of the programme in a larger sample. 相似文献