全文获取类型
收费全文 | 3709篇 |
免费 | 268篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 26篇 |
儿科学 | 144篇 |
妇产科学 | 92篇 |
基础医学 | 546篇 |
口腔科学 | 73篇 |
临床医学 | 421篇 |
内科学 | 845篇 |
皮肤病学 | 77篇 |
神经病学 | 346篇 |
特种医学 | 108篇 |
外科学 | 378篇 |
综合类 | 15篇 |
一般理论 | 3篇 |
预防医学 | 297篇 |
眼科学 | 53篇 |
药学 | 267篇 |
中国医学 | 8篇 |
肿瘤学 | 297篇 |
出版年
2023年 | 40篇 |
2022年 | 60篇 |
2021年 | 129篇 |
2020年 | 81篇 |
2019年 | 99篇 |
2018年 | 96篇 |
2017年 | 69篇 |
2016年 | 110篇 |
2015年 | 108篇 |
2014年 | 124篇 |
2013年 | 182篇 |
2012年 | 252篇 |
2011年 | 259篇 |
2010年 | 141篇 |
2009年 | 108篇 |
2008年 | 207篇 |
2007年 | 220篇 |
2006年 | 205篇 |
2005年 | 195篇 |
2004年 | 169篇 |
2003年 | 153篇 |
2002年 | 161篇 |
2001年 | 69篇 |
2000年 | 53篇 |
1999年 | 61篇 |
1998年 | 40篇 |
1997年 | 28篇 |
1996年 | 17篇 |
1995年 | 16篇 |
1994年 | 23篇 |
1992年 | 38篇 |
1991年 | 32篇 |
1990年 | 29篇 |
1989年 | 25篇 |
1988年 | 29篇 |
1987年 | 19篇 |
1986年 | 24篇 |
1985年 | 19篇 |
1984年 | 21篇 |
1983年 | 20篇 |
1982年 | 15篇 |
1981年 | 10篇 |
1979年 | 18篇 |
1978年 | 12篇 |
1977年 | 11篇 |
1976年 | 10篇 |
1973年 | 10篇 |
1972年 | 11篇 |
1969年 | 9篇 |
1966年 | 10篇 |
排序方式: 共有3996条查询结果,搜索用时 31 毫秒
111.
Frank Serge Lehmann Francesca Trapani Ida Fueglistaler Luigi Maria Terracciano Markus von Flüe Gieri Cathomas Andreas Zettl Pascal Benkert Daniel Oertli Christoph Beglinger 《World journal of gastroenterology : WJG》2014,20(17):4994-4999
AIM:To determine calprotectin release before and after colorectal cancer operation and compare it to tumor and histopathological parameters.METHODS:The study was performed on patients with diagnosed colorectal cancer admitted for operation.Calprotectin was measured in a single stool sample before and three months after the operation using an enzymelinked immunosorbent assay(ELISA).Calprotectin levels greater than or equal to 50μg/g were considered positive.The compliance for collecting stool samples was assessed and the value of calprotectin was correlated to tumor and histopathological parameters of intra-and peri-tumoral inflammation.Surgical specimens were fixed in neutral buffered formalin and stained with hematoxylin and eosin.Staging was performed according to the Dukes classification system and the 7th edition tumor node metastasis classification system.Intra-and peri-tumoral inflammation was graded according to the Klintrup criteria.Immunohistochemical quantification was performed for MPO,CD45R0,TIA-1,CD3,CD4,CD8,CD57,and granzyme B.Statistical significance was measured using Wilcoxon signed rank test,Kruskal Wallis test and Spearman’s rank correlation coefficient as appropriate.RESULTS:Between March 2009 and May 2011,80 patients with colorectal cancer(46 men and 34 women,with mean age of 71±11.7 years old)were enrolled in the study.Twenty-six patients had rectal carcinoma,29 had left-side tumors,23 had right-side tumors,and2 had bilateral carcinoma.In total,71.2%of the patients had increased levels of calprotectin before the operation(median 205μg/g,range 50-2405μg/g)and experienced a significant decrease three months after the operation(46μg/g,range 10-384μg/g,P<0001).The compliance for collecting stool samples was 89.5%.Patients with T3 and T4 tumors had significantly higher values than those with T1 and T2 cancers(P=0.022).For all other tumor parameters(N,M,G,L,V,Pn)and location,no significant difference in calprotectin concentration was found.Furthermore,the calprotectin levels and histological grading of both peri-and intra-tumoral inflammation was not correlated.Additional testing with specific markers for lymphocytes and neutrophils also revealed no statistically significant correlation.CONCLUSION:Fecal calprotectin decreases significantly after colorectal cancer operation.Its value depends exclusively on the individual T-stage,but not on other tumor or histopathological parameters. 相似文献
112.
Lene Hansen Lars Christian PetersenBrian Lauritzen Jes Thorn ClausenSusanne Nedergaard Grell Henrik AgersøBrit Binow Sørensen Ida HildenKasper Almholt 《Thrombosis research》2014
Introduction
A humanised monoclonal antibody, concizumab, that binds with high affinity to the Kunitz-type protease inhibitor (KPI) 2 domain of human tissue factor pathway inhibitor (TFPI) is in clinical development. It promotes coagulation by neutralising the inhibitory function of TFPI and may provide a subcutaneous prophylaxis option for patients with haemophilia. We aimed to study biodistribution and pharmacokinetics (PK) of concizumab.Materials and Methods
Blockage of cellular TFPI by concizumab was measured by tissue factor/Factor VIIa-mediated Factor X activation on human EA.hy926 cells. Biodistribution of concizumab was analysed in rabbits by immunohistology, and the PK was measured in rabbits and rats.Results and Conclusions
Concizumab bound to cell surface TFPI on EA.hy926 cells and neutralised TFPI inhibition of Factor X activation. The antibody cross-reacted with rabbit TFPI, but not with rat TFPI, allowing for comparative PK studies. PK data in rats described a log-linear profile typical for a non-binding antibody, whereas PK data in rabbits revealed a non-linear, dose-dependent profile, consistent with a target-mediated clearance mechanism. Immunohistology in rabbits during target-saturation showed localisation of the antibody on the endothelium of the microvasculature in several organs. We observed a marked co-localisation with endogenous rabbit TFPI, but a negligible sub-endothelial build-up. Concizumab binds and neutralises the inhibitory effect of cell surface-bound TFPI. The PK profile observed in rabbits is consistent with a TFPI-mediated drug disposition. Double immunofluorescence shows co-localisation of the antibody with TFPI on the endothelium of the microvasculature and points to this TFPI as a putative target involved in the clearance mechanism. 相似文献113.
Aizawa Y Jastrzebski M Ozawa T Kawecka-Jaszcz K Kukla P Mitsuma W Chinushi M Ida T Aizawa Y Ojima K Tagawa M Fujita S Okabe M Tsuchida K Miyakita Y Shimizu H Ito S Imaizumi T Toba K 《Journal of electrocardiology》2012,45(3):252-259
Background and PurposeSome de- and re-polarization patterns can reflect an increased risk of ventricular tachyarrhythmias. We studied whether some electrocardiographic (ECG) patterns are able to predict the development of ventricular fibrillation (VF) during acute myocardial infarction (MI).MethodsWe compared the patterns of ST-T segment of 78 patients who developed VF during acute MI (patient with VF) vs 170 comparable patients with acute MI but with no VF complications.ResultsOf the VF group, 47 developed out-of-hospital VF and 31 developed VF after their admission to the hospital. A steep downsloping ST segment toward a negative T wave with or without a short, flat, or rising portion at the initial portion was observed in 69.2% of the 78 patients: 61.3% in patients with pre-VF and 74.5% in patients with post-VF, vs 9.4% of patients who did not develop VF (P < .0001). In 90.6% of the latter, a typical upward-concave or convex “ischemic” pattern of the ST segment was observed. Thus, the characteristic ST-T patterns were highly associated with VF with a specificity greater than 90%.ConclusionsA steep downsloping ST segment may characterize the ECGs of patients who develop VF during acute MI. 相似文献
114.
115.
Zhou M Ottenberg G Sferrazza GF Lasmézas CI 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(8):3113-3118
Prion diseases are infectious and belong to the group of protein misfolding neurodegenerative diseases. In these diseases, neuronal dysfunction and death are caused by the neuronal toxicity of a particular misfolded form of their cognate protein. The ability to specifically target the toxic protein conformer or the neuronal death pathway would provide powerful therapeutic approaches to these diseases. The neurotoxic forms of the prion protein (PrP) have yet to be defined but there is evidence suggesting that at least some of them differ from infectious PrP (PrP(Sc)). Herein, without making an assumption about size or conformation, we searched for toxic forms of recombinant PrP after dilution refolding, size fractionation, and systematic biological testing of all fractions. We found that the PrP species most neurotoxic in vitro and in vivo (toxic PrP, TPrP) is a monomeric, highly α-helical form of PrP. TPrP caused autophagy, apoptosis, and a molecular signature remarkably similar to that observed in the brains of prion-infected animals. Interestingly, highly α-helical intermediates have been described for other amyloidogenic proteins but their biological significance remains to be established. We provide unique experimental evidence that a monomeric α-helical form of an amyloidogenic protein represents a cytotoxic species. Although toxic PrP has yet to be purified from prion-infected brains, TPrP might be the equivalent of one highly neurotoxic PrP species generated during prion replication. Because TPrP is a misfolded, highly neurotoxic form of PrP reproducing several features of prion-induced neuronal death, it constitutes a useful model to study PrP-induced neurodegenerative mechanisms. 相似文献
116.
Livshits G Malkin I Williams FM Hart DJ Hakim A Spector TD 《Age (Dordrecht, Netherlands)》2012,34(5):1285-1294
The importance of changing patterns of obesity in society and its implications for public health are well recognized. However, the adult life course of body mass index (BMI) changes in individuals over time is largely unknown and has mostly been extrapolated from cross-sectional studies. The present study examines individual specific variation of BMI during a 15-year follow-up period in a community-based sample of UK females. We attempted to establish whether there is a common, generalized pattern which captures variation in BMI over time. The participants of this study belong to a prospective population cohort of British women studied intensively since 1989: the Chingford Study. The sample originally consisted of 1,003 women aged 45-68 years, who were assessed annually for BMI during follow-up period. Polynomial regression models were used to assess longitudinal BMI variation. We observed a great stability in individual BMI variation during the follow-up period, reflected by high correlations between the baseline BMI and follow-up BMI 10 and 15 years later (r = 0.876, N = 810, and r = 0.824, N = 638, respectively). We also found that three different major age-related patterns in BMI could be clearly identified: no change in 30.6% in 58% it increased and in 11.4% it decreased with age. Thus, our data suggest that individual age-related changes in BMI are very different. Therefore, simply combining all individuals into groups by any other criteria (age, sex, etc.) and overlooking the distinctive patterns of BMI change may lead to biased inferences in epidemiologic and etiologic research of the future. 相似文献
117.
118.
Ichinose K Origuchi T Kawashiri SY Iwamoto N Fujikawa K Aramaki T Kamachi M Arima K Tamai M Nakamura H Ida H Kawakami A Eguchi K 《Rheumatology international》2012,32(2):483-487
We present six cases of patients with Japanese rheumatoid arthritis (RA) treated with a tumor necrosis factor (TNF)-alpha blocking agent, adalimumab as monotherapy for 220?weeks. All six patients were women, and the median age was 54.0?±?7.07?years old. The median duration of the disease was 7.43?±?11.1?years, and the median disease activity score (DAS28-CRP) was 5.35?±?0.69. Three of six patients were able to continue to receive this treatment for 220?weeks successfully, and the DAS28-CRP decreased to 1.89?±?0.75. Two patients withdrew because of lack of efficacy, and one patient withdrew because of adverse events (non-Hodgkin lymphoma). Adalimumab resulted in a sustained clinical response in RA patients during 220-week follow-up. 相似文献
119.
120.