全文获取类型
收费全文 | 997555篇 |
免费 | 75068篇 |
国内免费 | 2616篇 |
专业分类
耳鼻咽喉 | 12961篇 |
儿科学 | 34464篇 |
妇产科学 | 28460篇 |
基础医学 | 145275篇 |
口腔科学 | 27714篇 |
临床医学 | 90265篇 |
内科学 | 193541篇 |
皮肤病学 | 22912篇 |
神经病学 | 79106篇 |
特种医学 | 38385篇 |
外国民族医学 | 305篇 |
外科学 | 149483篇 |
综合类 | 23738篇 |
一般理论 | 385篇 |
预防医学 | 77818篇 |
眼科学 | 22606篇 |
药学 | 71860篇 |
3篇 | |
中国医学 | 2029篇 |
肿瘤学 | 53929篇 |
出版年
2018年 | 10555篇 |
2017年 | 8235篇 |
2016年 | 9373篇 |
2015年 | 10594篇 |
2014年 | 14415篇 |
2013年 | 22000篇 |
2012年 | 28980篇 |
2011年 | 30824篇 |
2010年 | 18487篇 |
2009年 | 17435篇 |
2008年 | 28786篇 |
2007年 | 30459篇 |
2006年 | 30959篇 |
2005年 | 29637篇 |
2004年 | 28924篇 |
2003年 | 27796篇 |
2002年 | 26812篇 |
2001年 | 46924篇 |
2000年 | 48033篇 |
1999年 | 40262篇 |
1998年 | 11177篇 |
1997年 | 10095篇 |
1996年 | 10160篇 |
1995年 | 9775篇 |
1994年 | 9090篇 |
1993年 | 8480篇 |
1992年 | 32248篇 |
1991年 | 31458篇 |
1990年 | 31006篇 |
1989年 | 29874篇 |
1988年 | 27167篇 |
1987年 | 27325篇 |
1986年 | 25434篇 |
1985年 | 24601篇 |
1984年 | 18397篇 |
1983年 | 15515篇 |
1982年 | 9288篇 |
1981年 | 8375篇 |
1979年 | 16859篇 |
1978年 | 12217篇 |
1977年 | 10314篇 |
1976年 | 9754篇 |
1975年 | 10178篇 |
1974年 | 12317篇 |
1973年 | 11843篇 |
1972年 | 10884篇 |
1971年 | 10113篇 |
1970年 | 9375篇 |
1969年 | 8724篇 |
1968年 | 8104篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
941.
942.
Stereological evaluation of liver volume in living donor liver transplantation using MDCT via the Cavalieri method. 总被引:4,自引:0,他引:4
Cihan Duran Bulent Aydinli Yaman Tokat Yildiray Yuzer Mecit Kantarci Metin Akgun Kamil Yalcin Polat Bünyami Unal Refik Killi S Selcuk Atamanalp 《Liver transplantation》2007,13(5):693-698
In living donor liver transplantation (LDLT), obtaining the precise volume of the graft is very important to decrease volume-related postoperative complications, especially in cases with suspected small-for size grafts. We used stereology based on the Cavalieri method (CM), a new method to measure liver graft volume, and compared the results with those obtained through intraoperative measurement (IOM) and through multidetector computed tomography (MDCT) measurement. Liver volumes estimated using the 3 methods were well-correlated with each other (r(2) = 0.94 and P < 0.001 for IOM and CM; r(2) = 0.91 and P < 0.001 for IOM and MDCT, and r(2) = 0.95 and P < 0.001 for CM and MDCT); however, they were different from each other (in descending order, 908 +/- 124 cm(2), 861 +/- 121 cm(2), and 777 +/- 168 cm(2) for MDCT, CM, and IOM, respectively). Although MDCT and CM overestimated the volumes, the results of CM were almost similar to those obtained via IOM. In conclusion, our results suggest that CM measured the liver graft volume more reliably. Thus, its use, particularly in cases with suspected small-for-size graft, may prove useful. 相似文献
943.
A. S. Mühlfeld M. Ketteler K. Schwamborn F. Eitner B. Schneider U. Gladziwa R. Knüchel J. Floege 《American journal of transplantation》2007,7(7):1865-1868
Sticky platelet syndrome (SPS) leads to hyperaggregabilty of platelets in response to physiologic stimuli. In this report we describe three patients with clinical symptoms of SPS after renal transplantation. The first patient developed an infarction of her transplant kidney with additional, subsequent renal microinfarctions. The second patient suffered multiple strokes and deep vein thrombosis with episodes of pulmonary embolism and ischemic bowel disease due to colonic microinfarctions. The third patient experienced a long episode of unexplained respiratory and graft dysfunction immediately after transplantation until therapy for SPS was initiated, at which point symptoms resolved quickly. Kidney transplant recipients with SPS may be at increased risk of developing thrombosis, given that most immunosuppressive drugs are known to induce either endothelial cell damage or augment platelet aggregation. All patients awaiting renal transplantation should be screened for a history of thrombosis and, if appropriate, tested for SPS. Affected patients should receive dose-adjusted acetylsalicylic acid. 相似文献
944.
R. A. Wolfe F. B. LaPorte A. M. Rodgers E. C. Roys G. Fant A. B. Leichtman 《American journal of transplantation》2007,7(S1):1404-1411
Turndowns of offers of deceased donor kidneys for transplantation can contribute to inefficiencies in the organ distribution system and inequality in access to donated organs. Match run data were obtained for 4967 'good' kidneys placed and transplanted in 2005 after fewer than 50 offers. These kidneys were not recovered from donation after cardiac death or expanded criteria donors, or from donors with a history of substance abuse. On average, these good kidneys were not accepted until after seven offers to candidates and after offers to 2.4 programs. Models for the likelihood of acceptance found several donor and candidate characteristics to be significantly related to acceptance rates (p < 0.05). After accounting for these variables, there remained 2- to 3-fold differences among transplant programs in acceptance rates. These models could be used to identify kidney transplant centers with exceptional acceptance practices. Several strategies might be employed to increase acceptance rates for good organs. 相似文献
945.
A K Konstantinidis S J Barton I Sayers I A Yang J L Lordan S Rorke J B Clough S T Holgate J W Holloway 《The European respiratory journal》2007,30(1):40-47
Interleukin (IL)-13 plays a central role in asthma pathogenesis by binding to the IL-13 receptor, which is a heterodimer composed of the IL-13 receptor alpha1 subunit (IL-13Ralpha1) and IL-4Ralpha. The genetic diversity at the IL-13Ralpha1 gene (IL13RA1) locus on chromosome Xq24 was characterised and the association of identified polymorphisms with asthma and atopy phenotypes examined. The promoter and coding region of IL13RA1 were screened for common genetic variants, and polymorphisms found were genotyped in a large cohort of 341 asthmatic Caucasian families (each containing at least two asthmatic siblings) and 182 nonasthmatic control subjects. Genetic association was determined using case-control and transmission disequilibrium test analyses. Two common polymorphisms were identified, a newly found thymidine (T) to guanine (G) transition of nucleotide -281 (-281T>G) single nucleotide polymorphism in the IL13RA1 promoter and the previously described 1365A>G variant in the IL13RA1 proximal 3' untranslated region. No significant association of either -281T>G or 1365A>G with risk of asthma or atopy phenotypes was found, apart from a suggestive association between the IL13RA1 -281T/1365A haplotype and raised total serum immunoglobulin E levels in adult female asthmatics. These findings indicate that the interleukin-13 receptor alpha1 subunit gene -281T>G and 1365A>G polymorphisms do not contribute to asthma susceptibility or severity, although the interleukin-13 receptor alpha1 subunit gene locus might be involved in the control of immunoglobulin E production. 相似文献
946.
947.
Conger KB 《Annals of surgery》1941,113(6):1105-1106
948.
J. M. McGree J. A. Eccleston S. B. Duffull 《Journal of pharmacokinetics and pharmacodynamics》2009,36(2):101-123
We consider nested multiple response models which are used extensively in the area of pharmacometrics. Given the conditional
nature of such models, differences in predicted responses are a consequence of different assumptions about how the models
interact. As such, sequential versus simultaneous and First Order (FO) versus First Order Conditional Estimation (FOCE) techniques
have been explored in the literature where it was found that the sequential and FO approaches can produce biased results.
It is therefore of interest to determine any design consequences between the various methods and approximations. As optimal
design for nonlinear mixed effects models is dependent upon initial parameter estimates and an approximation to the expected
Fisher information matrix, it is necessary to incorporate any influence of nonlinearity (or parameter-effects curvature) into
our exploration. Hence, sequential versus simultaneous design with FO and FOCE considerations are compared under low, typical
and high degrees of nonlinearity. Additionally, predicted standard errors of parameters are also compared to empirical estimates
formed via a simulation/estimation study in NONMEM. Initially, design theory for nested multiple response models is developed
and approaches mentioned above are investigated by considering a pharmacokinetic–pharmacodynamic model found in the literature.
We consider design for situations where all responses are continuous and extend this methodology to the case where a response
may be a discrete random variable. In particular, for a binary response pharmacodynamic model, it is conjectured that such
responses will offer little information about all parameters and hence a sequential optimization, in the form of product design
optimality, may yield near optimal designs. 相似文献
949.
950.