全文获取类型
收费全文 | 4230篇 |
免费 | 430篇 |
国内免费 | 116篇 |
专业分类
耳鼻咽喉 | 32篇 |
儿科学 | 118篇 |
妇产科学 | 88篇 |
基础医学 | 257篇 |
口腔科学 | 106篇 |
临床医学 | 441篇 |
内科学 | 944篇 |
皮肤病学 | 80篇 |
神经病学 | 464篇 |
特种医学 | 151篇 |
外科学 | 692篇 |
综合类 | 311篇 |
现状与发展 | 1篇 |
预防医学 | 423篇 |
眼科学 | 32篇 |
药学 | 287篇 |
中国医学 | 129篇 |
肿瘤学 | 220篇 |
出版年
2024年 | 7篇 |
2023年 | 106篇 |
2022年 | 153篇 |
2021年 | 213篇 |
2020年 | 211篇 |
2019年 | 232篇 |
2018年 | 257篇 |
2017年 | 189篇 |
2016年 | 183篇 |
2015年 | 175篇 |
2014年 | 345篇 |
2013年 | 314篇 |
2012年 | 218篇 |
2011年 | 273篇 |
2010年 | 196篇 |
2009年 | 192篇 |
2008年 | 207篇 |
2007年 | 167篇 |
2006年 | 155篇 |
2005年 | 116篇 |
2004年 | 106篇 |
2003年 | 100篇 |
2002年 | 79篇 |
2001年 | 56篇 |
2000年 | 45篇 |
1999年 | 55篇 |
1998年 | 40篇 |
1997年 | 29篇 |
1996年 | 41篇 |
1995年 | 34篇 |
1994年 | 28篇 |
1993年 | 28篇 |
1992年 | 20篇 |
1991年 | 23篇 |
1990年 | 19篇 |
1989年 | 14篇 |
1988年 | 20篇 |
1987年 | 8篇 |
1986年 | 11篇 |
1985年 | 21篇 |
1984年 | 18篇 |
1983年 | 9篇 |
1982年 | 10篇 |
1981年 | 14篇 |
1980年 | 13篇 |
1979年 | 2篇 |
1978年 | 8篇 |
1977年 | 2篇 |
1976年 | 8篇 |
1975年 | 5篇 |
排序方式: 共有4776条查询结果,搜索用时 15 毫秒
11.
L. Matsuoka T. Shah S. Aswad S. Bunnapradist Y. Cho R. G. Mendez R. Mendez R. Selby 《American journal of transplantation》2006,6(6):1473-1478
The use of expanded criteria donors (ECD) has been proposed to help combat the discrepancy between organ availability and need. ECD kidneys are associated with delayed graft function (DGF) and worse long-term survival. The aim of this study is to evaluate the impact of pulsatile perfusion (PP) on DGF and graft survival in transplanted ECD kidneys. From January 2000 to December 2003, 4618 ECD kidney-alone transplants were reported to the United Network for Organ Sharing. PP was performed on 912 renal allografts. The prognostic factors of DGF were analyzed using multivariate logistic regression analysis. Risk factors for reduced allograft viability were greater in donors and recipients of PP kidneys. Three-year graft survival of ECD kidneys preserved with PP was similar to cold storage (CS) kidneys. The incidence of DGF in PP kidneys was significantly lower than CS kidneys (26% vs. 36%, p < 0.001). Despite having a greater number of risk factors for reduced graft viability, the ECD-PP kidneys had similar graft survival compared to ECD-CS kidneys. The use of PP, by decreasing the incidence of DGF, may possibly lead to lower overall costs and increased utilization of donor kidneys. 相似文献
12.
The Broad Spectrum of Quality in Deceased Donor Kidneys 总被引:7,自引:6,他引:1
Jesse D. Schold Bruce Kaplan Rajendra S. Baliga Herwig-Ulf Meier-Kriesche 《American journal of transplantation》2005,5(4):757-765
The quality of the deceased donor organ clearly is one of the most crucial factors in determining graft survival and function in recipients of a kidney transplant. There has been considerable effort made towards evaluating these organs culminating in an amendment to allocation policy with the introduction of the expanded criteria donor (ECD) policy.
Our study, from first solitary adult deceased donor transplant recipients from 1996 to 2002 in the National Scientific Transplant Registry database, presents a donor kidney risk grade based on significant donor characteristics, donor–recipient matches and cold ischemia time, generated directly from their risk for graft loss. We investigated the impact of our donor risk grade in a naïve cohort on short- and long-term graft survival, as well as in subgroups of the population.
The projected half-lives for overall graft survival in recipients by donor risk grade were I (10.7 years), II (10.0 years), III (7.9 years), IV (5.7 years) and V (4.5 years). This study indicates that there is great variability in the quality of deceased donor kidneys and that the assessment of risk might be enhanced by this scoring system as compared to the simple two-tiered system of the current ECD classification. 相似文献
Our study, from first solitary adult deceased donor transplant recipients from 1996 to 2002 in the National Scientific Transplant Registry database, presents a donor kidney risk grade based on significant donor characteristics, donor–recipient matches and cold ischemia time, generated directly from their risk for graft loss. We investigated the impact of our donor risk grade in a naïve cohort on short- and long-term graft survival, as well as in subgroups of the population.
The projected half-lives for overall graft survival in recipients by donor risk grade were I (10.7 years), II (10.0 years), III (7.9 years), IV (5.7 years) and V (4.5 years). This study indicates that there is great variability in the quality of deceased donor kidneys and that the assessment of risk might be enhanced by this scoring system as compared to the simple two-tiered system of the current ECD classification. 相似文献
13.
14.
15.
16.
17.
目的 评价Manning标准诊断肠易激综合征(IBS)的真实性。方法 采用自行设计的调查表对499例对象进行调查。结果 1.随着Manning标准中结合指标数的增多,IBS组与非溃疡性消化不良及溃疡性结肠炎组鉴别的灵敏度及其95%CI明显下降,特异度及其95%CI明显上升,同时阳性预测值、阳性似然比及阴性似然比也明显上升。2.符合Manning标准中二项以上结合指标,IBS组就具有较好与健康对照组鉴别的灵敏度及其95%CI、特异度及其95%CI。结论 Manning标准中需要3项以上结合指标可较好地使IBS与非溃疡性消化不良或溃疡性结肠炎鉴别;2项以上结合指标可较好地使IBS与健康人鉴别。 相似文献
18.
D. M. Jensen P. Damm B. Sørensen L. Mølsted-Pedersen J. G. Westergaard L. Korsholm P. Ovesen H. Beck-Nielsen 《Diabetic medicine》2003,20(1):51-57
AIMS: To study if established diagnostic threshold values for gestational diabetes based on a 75-g, 2-h oral glucose tolerance test can be supported by maternal and perinatal outcomes. METHODS: Historical cohort study of 3260 pregnant women examined for gestational diabetes on the basis of risk indicators. Information on oral glucose tolerance test results and clinical outcomes were collected from medical records. RESULTS: There was an increased risk of delivering a macrosomic infant in women with 2-h capillary blood glucose of 7.8-8.9 mmol/l compared with women with 2-h glucose < 7.8 mmol/l. Despite treatment, 2-h glucose of 9.0-11.0 mmol/l and > or = 11.1 mmol/l were both associated with increased rates of macrosomia, spontaneous preterm delivery, hypertensive complications, and neonatal hypoglycaemia. Adverse outcomes tended to be more frequent in women with 2-h glucose > or = 11.1 mmol/l than in women with 2-h glucose of 9.0-11.0 mmol/l. CONCLUSIONS: The risk for several maternal and perinatal complications increased with the diagnostic threshold for 2-h glucose. Large-scale blinded studies are needed to clarify the question of a clinically meaningful diagnosis of gestational diabetes mellitus. Until these results are available, a 2-h threshold level of 9.0 mmol/l after a 75-g oral glucose tolerance test seems acceptable. 相似文献
19.
D De AJ Kanwar S Handa 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):853-859
BACKGROUND: Diagnosis of atopic dermatitis (AD) depends on clinical features because no definitive diagnostic test exists. Criteria proposed by Hanifin and Rajka (Acta Derm Venereol (Stockh) 1980; Suppl 92: 44-47) were acceptable for hospital-based studies but were found not to be suitable for field studies. A UK working party formulated clinical diagnostic criteria that could be used in both hospital and epidemiological settings. Validation studies of the criteria showed widely variable results, probably due to different clinical settings and ethnicity. AIM AND OBJECTIVE: This study was undertaken to validate Hanifin and Rajka's criteria and to assess the comparative efficacy of their criteria and the UK working party's diagnostic criteria in the diagnosis of AD in a hospital setting in North India. SUBJECTS AND METHODS: This study serially included 101 patients with AD and 48 controls of paediatric age group. The study period was from July 2003 to December 2004. RESULTS: Hanifin and Rajka's criteria (sensitivity 96%, specificity 93.75%, positive predictive value 97% (PPV) and negative predictive value (NPV) 91.84%) had a statistical advantage over the UK working party's diagnostic criteria (sensitivity 86%, specificity 95.83%, PPV 97.75% and NPV 76.67%), with a P-value < 0.005. 相似文献
20.