全文获取类型
收费全文 | 1066篇 |
免费 | 104篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 32篇 |
妇产科学 | 24篇 |
基础医学 | 189篇 |
口腔科学 | 59篇 |
临床医学 | 122篇 |
内科学 | 217篇 |
皮肤病学 | 16篇 |
神经病学 | 70篇 |
特种医学 | 43篇 |
外科学 | 155篇 |
综合类 | 16篇 |
一般理论 | 1篇 |
预防医学 | 87篇 |
眼科学 | 27篇 |
药学 | 50篇 |
中国医学 | 6篇 |
肿瘤学 | 42篇 |
出版年
2024年 | 3篇 |
2023年 | 16篇 |
2022年 | 30篇 |
2021年 | 38篇 |
2020年 | 34篇 |
2019年 | 59篇 |
2018年 | 40篇 |
2017年 | 44篇 |
2016年 | 26篇 |
2015年 | 42篇 |
2014年 | 43篇 |
2013年 | 63篇 |
2012年 | 64篇 |
2011年 | 58篇 |
2010年 | 35篇 |
2009年 | 32篇 |
2008年 | 50篇 |
2007年 | 55篇 |
2006年 | 31篇 |
2005年 | 26篇 |
2004年 | 24篇 |
2003年 | 16篇 |
2002年 | 15篇 |
2001年 | 22篇 |
2000年 | 21篇 |
1999年 | 22篇 |
1998年 | 6篇 |
1997年 | 9篇 |
1996年 | 7篇 |
1995年 | 6篇 |
1994年 | 12篇 |
1993年 | 4篇 |
1992年 | 21篇 |
1991年 | 19篇 |
1990年 | 16篇 |
1989年 | 16篇 |
1988年 | 24篇 |
1987年 | 15篇 |
1986年 | 13篇 |
1985年 | 11篇 |
1984年 | 15篇 |
1983年 | 10篇 |
1982年 | 4篇 |
1981年 | 6篇 |
1980年 | 4篇 |
1979年 | 20篇 |
1978年 | 7篇 |
1974年 | 3篇 |
1973年 | 2篇 |
1915年 | 2篇 |
排序方式: 共有1171条查询结果,搜索用时 15 毫秒
51.
Objective:Dysregulation of lncRNAs and the absence of coordination between them could affect the normal placentation, uteroplacental circulation, and endothelial cell function. All these misfunctions can finally lead to preeclampsia.
Methods: In the present review, we discuss current literature (till May 2018) about lncRNAs expression and function in the placenta, trophoblast cells, and decidua.
Results and conclusion: It is explained how altered expression of the lncRNAs and abnormal regulation of them affect the risk of preeclampsia. However, the interaction between various lncRNAs and coordinate regulation of them in health and failure of such coordinative mechanisms in diseases such as preeclampsia need to be elucidated. 相似文献
52.
53.
J. C. van Es 《The British journal of general practice》1972,22(118):291-296
54.
M J Nubé G G Persijn A van Es M W Kalff J de Graeff J J van Rood 《Transplantation》1983,35(6):556-561
The effects of HLA-A and B matched pretransplant blood transfusions on the survival of a primary cadaveric kidney graft were studied prospectively in a group of 15 patients who had never received a transfusion and had never been pregnant. Kidney graft survival at one year was 87%, whereas a group of 14 nontransfused patients who underwent transplantation in the same center (before this study was initiated) had a graft survival of only 7%. Twenty-six patients who received a transplant in the same center just before and after each protocol patient served as controls. There were no prior pregnancies in this group; all patients had received blood transfusions from random blood bank donors. Kidney graft survival at one year was 76% for this control group, which is not statistically different from that found for the protocol group. Graft survival for the 13 contralateral kidneys from the protocol group donors was only 50% at one year. These kidneys, however, were transplanted in various other centers. From our study, prolongation of kidney graft survival could be demonstrated for patients receiving pretransplant HLA-A-and-B-matched blood transfusions. Sera screening indicated that lymphocytotoxicity might be reduced by pretransplant HLA-A-and-B-matched blood transfusions. The presence of pretransplant antibodies with specificities for HLA-A and/or B could be significantly correlated with poor graft survival. 相似文献
55.
56.
Effect of warm ischemia time and HLA (A and B) matching on renal cadaveric graft survival and rejection episodes 总被引:1,自引:0,他引:1
A van Es J Hermans J H van Bockel G G Persijn J P van Hooff J de Graeff 《Transplantation》1983,36(3):255-258
In a retrospective single-center study the influence of warm ischemia time and simultaneous influence of HLA (A and B) matching on one-year renal graft survival was analyzed in 170 adult recipients of primary cadaveric renal grafts. One-year survival of grafts with warm ischemia times longer than 50 min was only 40% (n = 10). When warm ischemia time was shorter than 50 min, a 1-min increase of warm ischemia time correlated with 1% decrease in one-year graft survival as a result of rejection. This detrimental effect of warm ischemia time on graft survival was not yet significant one month after transplantation, but became more evident as follow-up time was lengthened. Warm ischemia time also correlated with the number of reversible rejection episodes in patients with a graft functioning for longer than one year (P less than 0.04). The beneficial influence of HLA (A and B) matching on one-year graft survival was significant (P less than 0.05 log linear test). This influence was even more evident with longer warm ischemia times. It is concluded that warm ischemia has a detrimental influence on graft survival that is mediated by rejection, and it is suggested that this might be due in part to altered presentation or expression of HLA-antigens of ischemically damaged kidney tissues. 相似文献
57.
58.
Kheradvar A Tabassi AR Nikbin B Khosravi F Naroueynejad M Moradi B Amirzargar AA 《Multiple sclerosis (Houndmills, Basingstoke, England)》2004,10(5):526-531
BACKGROUND: Genetic predisposition in multiple sclerosis (MS) has always been a critical concern in aetiology and progress of the disease. The present study looks into the relations between human leukocyte antigen (HLA), optic neuritis (ON) and MS in the Iranian population. METHODS: Patients with potential diagnosis of acute ON underwent a standardized clinical examination for confirming the diagnosis. Selected patients were gathered for HLA typing and clinical follow up. RESULTS: Of the 55 patients, 46 (83.6%) were female. The mean age was 25(+/-7.3) with a range of 12-43. Twenty of the 55 (36%) were confirmed for the diagnosis of clinically definite MS (CDMS). Results show that A23, B21, A11 and B51 alleles were present in 4 (20%), 6 (30%), 2 (10%) and 1 (5%) of the CDMS patients, respectively. Ten (50%) and 17 (85%) CDMS patients were positive for HLA class II alleles, DR2 and DQ1, correspondingly. CONCLUSIONS: The study strongly suggests the association among DR2, A23 and B21 allele and the evolution of ON to MS. High prevalence of A23 and DR2 alleles in CDMS patients compared with the normal population may suggest an important role for these alleles in the development of MS. The study suggests B51 as a protective factor against development of ON in the normal population. In addition, results do not confirm previous studies considering A11 as a predisposing factor. The present study finally evokes that different classes of HLA have different roles in susceptibility to MS and confirms disease heterogeneity as an important emerging concept in MS. 相似文献
59.
Durrani OM Tehrani NN Marr JE Moradi P Stavrou P Murray PI 《The British journal of ophthalmology》2004,88(9):1159-1162
BACKGROUND/AIMS: Uveitis is a major cause of visual morbidity in the working age group. The authors investigated the duration, degree, and causes of visual loss in uveitis patients with the aim of better defining the visual morbidity and identifying potential risk factors. METHODS: A retrospective, non-interventional, observational survey of 315 consecutive patients attending a tertiary referral uveitis service. RESULTS: The mean duration of follow up was 36.7 months. Reduced vision (< or =6/18) was found in 220/315 (69.95%) of the patients with a subset of 120 patients having vision < or =6/60. Unilateral visual loss occurred in 109 (49.54%), while 111 (50.45%) had bilateral loss. The mean duration of visual loss was 21 months. Of the 148 patients with pan-uveitis, 125 (84.45%) had reduced vision, with 66 (53%) having vision < or =6/60. Main causes of visual loss were cystoid macular oedema (CMO) (59/220, 26.8%), cataract (39/220, 17.7%), and combination of CMO and cataract (44/220, 20%). The following were predictive of a poorer visual prognosis: pan-uveitis (p = 0.0005), bilateral inflammation (p = 0.0005), increasing duration of reduced vision (p = 0.0005), an Indian or Pakistani ethnic background (p = 0.004), and increasing patient age (p = 0.02). CONCLUSION: Prolonged visual loss occurred in two thirds of uveitis patients, with 70 (22%) patients meeting the criteria for legal blindness at some point in their follow up. Older patients with bilateral inflammation and an increasing duration of reduced vision are at the greatest risk of severe visual loss (< or =6/60). CMO and cataract were responsible for visual loss in 64.5% of patients. 相似文献
60.
Howell E Chen YT Moradi M Concato J 《American journal of obstetrics and gynecology》2000,183(2):407-413
OBJECTIVE: This study was undertaken (1) to describe practice patterns for treatment of cervical cancer on a national scale, including patient characteristics associated with receiving appropriate versus inappropriate therapy, and (2) to determine whether mortality rate differences exist between patients who were treated appropriately and those who were treated inappropriately. STUDY DESIGN: We defined treatment appropriateness in cases of cervical cancer according to general recommendations for therapy for each International Federation of Gynecology and Obstetrics stage. In an analysis of data obtained from the Surveillance, Epidemiology, and End Results Program for 1988 through 1994 we determined the associations of patient demographic characteristics and tumor characteristics with treatment appropriateness. The association between treatment appropriateness and overall mortality for as long as 7 years of follow-up was adjusted for age; marital status; Surveillance, Epidemiology, and End Results Program location; International Federation of Gynecology and Obstetrics stage of disease; lymph node status; tumor grade; and histologic classification. RESULTS: Overall 90% of all patients were found to have received appropriate therapy. Important variables significantly associated with being treated inappropriately versus appropriately included age <40 years, positive nodal status, and International Federation of Gynecology and Obstetrics stage IB disease. Important variables significantly associated with receiving no therapy versus receiving appropriate therapy were age >/=60 years, International Federation of Gynecology and Obstetrics stage IV disease, positive nodal status, and unknown nodal status. In a comprehensive model that included demographic factors and tumor characteristics, the adjusted hazard ratio for mortality among patients who were treated inappropriately versus appropriately was 0.87 (95% confidence interval, 0.70-1.09). The adjusted hazard ratio for mortality among patients who did not receive therapy versus those who were treated appropriately was 2.92 (95% confidence interval, 2.44-3.48). CONCLUSIONS: In an analysis of data from a tumor registry, cervical cancer practice patterns were generally found to follow accepted treatment guidelines. Appropriateness of therapy did not vary widely according to demographic variables. Although patients who received no therapy had an elevated risk of death with respect to that of patients who were treated appropriately, patients who were treated inappropriately had a mortality rate similar to that among those who were treated appropriately (perhaps because of limitations in Surveillance, Epidemiology, and End Results Program data). Results of this preliminary study suggest a need for further research on effectiveness of cervical cancer therapies in the general population. 相似文献