全文获取类型
收费全文 | 570篇 |
免费 | 52篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 11篇 |
妇产科学 | 12篇 |
基础医学 | 164篇 |
口腔科学 | 28篇 |
临床医学 | 43篇 |
内科学 | 138篇 |
皮肤病学 | 13篇 |
神经病学 | 18篇 |
特种医学 | 3篇 |
外科学 | 75篇 |
综合类 | 1篇 |
预防医学 | 44篇 |
眼科学 | 3篇 |
药学 | 33篇 |
中国医学 | 3篇 |
肿瘤学 | 25篇 |
出版年
2023年 | 6篇 |
2022年 | 18篇 |
2021年 | 13篇 |
2020年 | 22篇 |
2019年 | 22篇 |
2018年 | 22篇 |
2017年 | 15篇 |
2016年 | 17篇 |
2015年 | 24篇 |
2014年 | 30篇 |
2013年 | 31篇 |
2012年 | 47篇 |
2011年 | 40篇 |
2010年 | 26篇 |
2009年 | 14篇 |
2008年 | 28篇 |
2007年 | 20篇 |
2006年 | 20篇 |
2005年 | 15篇 |
2004年 | 20篇 |
2003年 | 24篇 |
2002年 | 23篇 |
2001年 | 11篇 |
2000年 | 8篇 |
1999年 | 10篇 |
1998年 | 4篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1992年 | 8篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1975年 | 6篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1972年 | 3篇 |
1969年 | 2篇 |
1968年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有624条查询结果,搜索用时 0 毫秒
41.
Castoldi G Galimberti S Riva C Papagna R Querci F Casati M Zerbini G Caccianiga G Ferrarese C Baldoni M Valsecchi MG Stella A 《Clinical science (London, England : 1979)》2007,113(2):103-108
Diabetes mellitus accelerates atherosclerotic processes, and it is known that inflammation plays a key role in atherosclerosis. The aim of the present study was to evaluate in patients with Type 2 diabetes whether serum levels of CRP (C-reactive protein) are associated with cytokine production in whole blood. A total of 89 outpatients with Type 2 diabetes were enrolled, and blood pressure, body mass index, fasting blood glucose, glycated haemoglobin, cholesterol, triacylglycerols (triglycerides) and hs-CRP (high-sensitivity CRP) were measured. IL-6 (interleukin-6), IL-1beta (interleukin-1beta) and TNF-alpha (tumour necrosis factor-alpha) were measured before and after 24 h of incubation of whole blood with LPS (lipopolysaccharide) or saline. The basal values of IL-1beta, IL-6 and TNF-alpha were low and were not significantly related to hs-CRP levels. A univariate analysis showed that the level of IL-1beta and IL-6, obtained after 24 h of incubation of whole blood with LPS, increased significantly with increasing levels of hs-CRP and, after adjusting for potential confounders, IL-1beta still remained statistically significant. In our sample of patients with Type 2 diabetes, there was no association between serum hs-CRP levels and basal levels of IL-6, IL-1beta and TNF-alpha. Conversely, a significant association was observed between serum hs-CRP levels and IL-1beta and IL-6 production after 24 h of incubation of whole blood with LPS. In conclusion, our data suggest that patients with Type 2 diabetes and high hs-CRP levels may have an enhanced reactivity in response to specific stimuli that produce different interleukins, with possible implications in inflammatory atherosclerotic processes. 相似文献
42.
Carlo Mancini Giulio Pisani Alberta Azzi Maria Luisa Zerbini Giuliano Gentili Guillermo Mario Bisso MS participants 《Journal of clinical virology》2004,30(4):313-319
BACKGROUND: The importance of the standardisation of nucleic acid amplification technology (NAT) assays for the detection of hepatitis C virus RNA is well known today, as many studies carried out in different European countries attest. The results of a previous study performed in Italy (J. Clin. Virol. 1 (2003) 83) by the Italian Society of Clinical Microbiology (AMCLI) showed that the use of external reference standards and of multicentre collaborative studies significantly improves laboratory performance for the qualitative evaluation of HCV RNA. OBJECTIVES: the AMCLI organised a new study on the standardisation of both the qualitative and the quantitative evaluation of HCV RNA with NAT in order to improve the implementation of the diagnostic methods for HCV RNA detection. STUDY DESIGN: seventeen diagnostic centres of major Italian Hospitals participated in this quality control study. The study consisted of testing three panels, each made up of 10 coded samples including negative and positive samples. Positive samples contained four levels of HCV RNA (genotype 1). RESULTS AND CONCLUSION: Seven out of 510 qualitative results obtained were incorrect (1.4%), two false negative and five false positive. The results gave a sensitivity of 99.5% and a specificity of 95.8%. Regarding quantitative tests, the geometric mean (GM) and standard deviation (S.D.) could be calculated only for the three highest HCV RNA levels. The percentage of results within the range of GM +/- 0.5 log(10) varied from 91% to 100%. Some laboratories had some difficulty in the exact quantification of the lowest (3.00 log IU/ml) as well as of the highest viral levels (6.35 log IU/ml) values, very near to the limits of the dynamic range of the assays. The comparison of the results of this study with that previously carried out one confirms that a regular participation in external quality assessment (EQA) assures the achievement of a high proficiency level in the diagnosis of HCV infection. 相似文献
43.
M. Musiani A. Roda M. Zerbini P. Pasini G. Gentilomi G. Gallinella S. Venturoli 《The American journal of pathology》1996,148(4):1105-1112
A chemiluminescent in situ hybridization assay that could combine the sensitivity of chemiluminescent substrates, the specificity of digoxigenin-labeled probes, and the spatial morphological resolution and localization of the signal of the in situ hybridization was developed for the detection of cytomegalovirus (CMV) DNA. CMV DNA in cultured CMV-infected cells and in different clinical samples (tissue sections and cellular smears) was detected using digoxigenin-labeled probes constructed in our laboratory that were immunoenzymatically visualized employing anti-digoxigenin Fab fragments labeled with alkaline phosphatase and the chemiluminescent adamantil-1,2-dioxetane phenyl phosphate substrate for alkaline phosphatase. The luminescent signal from the hybrid formation was detected, analyzed, and measured with a high performance, low light level imaging luminograph apparatus connected to an optical microscope and to a personal computer for quantitative image analysis. Increasing values of emitted photons per second per infected cell, corresponding to the presence of hybridized CMV DNA, could be found in infected cells fixed at various times after infection, following the CMV replication cycle. When the assay was performed on different clinical samples from patients with acute CMV infections, CMV DNA was detected in all positive samples tested, both in cellular samples and in frozen and paraffin-embedded tissue sections, proving specific and sensitive. The chemiluminescent in situ hybridization assay developed in this work can be a useful tool for a sensitive and specific diagnosis of viral infection and can be easily adapted to detect and study any specific gene sequence inside the cells. The assay may also be promising for an estimation and quantification of nucleic acids present in tissue samples or cellular smears and for imaging gene expression in cells. 相似文献
44.
Elisabetta Manaresi Giorgio Gallinella Marialuisa Zerbini Simona Venturoli Giovanna Gentilomi Monica Musiani 《Journal of medical virology》1999,57(2):174-178
Human B19 parvovirus recombinant capsid proteins VP1 and VP2 were expressed in E. coli and purified. Recombinant proteins were used to detect a specific IgG immune response against VP1 and VP2 linear epitopes by immunoblot assay. A total of 222 serum samples from 218 apparently immunocompetent subjects with different clinical conditions and laboratory evaluations with regards to B19 infection were analyzed. The sera had previously been tested for B19 DNA and for specific IgM and IgG against VP2 conformational antigens by ELISA assay. The data show that, during the active or very recent phase of infection, IgG anti-VP1 linear epitopes appear in concomitance and with the same frequency as IgG anti-VP2 conformational antigens. IgG against conformational VP2 antigens and against linear VP1 epitopes seem to persist for months or years in the majority of individuals. IgG against VP2 linear epitopes are generally present during the active or very recent phase of infection and during the convalescent phase, while they are present only in about 20% of subjects with signs of a past B19 infection. J. Med. Virol. 57:174–178, 1999. © 1999 Wiley-Liss, Inc. 相似文献
45.
46.
Luana Alves Dummer Fabricio Rochedo Conceio Leandro Quintana Nizoli Carina Martins de Moraes Andra Ramos Rocha Lorena Leonardo de Souza Talita Roos Telmo Vidor Fbio Pereira Leivas Leite 《Journal of virological methods》2009,161(1):84-90
Meningoencephalitis caused by Bovine herpesvirus type 5 (BoHV-5) is responsible for heavy economic losses in the cattle industry. As in other Alphaherpesviruses, the envelope glycoprotein IV (gD), which mediates penetration into host cells, is one of the major candidate antigens for a recombinant vaccine, since it induces a strong and persistent immune response. The DNA coding for a truncated form of BoHV-5 gD (tgD) has been cloned into the Pichia pastoris expression vector pPICZαB to allow protein secretion into the medium. After induction with methanol, a 55 kDa protein was obtained. Enzyme deglycosylation with Endo H showed a smaller size band in SDS-PGAE, with 50 kDa, suggesting that tgD has N-linked oligosaccharides and that it is not hyperglycosylated. The 55 kDa protein was recognized by several polyclonal antibodies, including polyclonal antibody anti-tgD and polyclonal antibodies of different animal species immunized with BoHV-5 and BoHV-1. This is the first report of BoHV-5 gD expression in yeast. It was shown that the recombinant truncated form of BoHV-5 gD has antigenic and immunogenic properties similar to the native BoHV-5 gD. Expression of tgD as a secreted protein allows simple and inexpensive purification methods that can be used for further studies to evaluate its immunogenicity in cattle. 相似文献
47.
Thoracic and retroperitoneal spindle-cell lesions represent a diagnostic challenge in the evaluation of fine-needle aspiration (FNA) specimens. The challenge is due to the morphologic similarities and wide variety of different entities with spindle-cell morphology in these two sites. The purpose of this study was to identify criteria helpful in the classification and differential diagnosis of spindle-cell lesions in these two locations. A set of cytologic features was analyzed in 57 thoracic or retroperitoneal spindle-cell lesions. Our results show that pleomorphism and abundant single cells were parameters associated with high-grade tumors in univariate and multivariate analysis, while coarse chromatin pattern was significant only in a univariate analysis. The combination of absence of pleomorphism, rare single cells, tight cluster arrangement, fine chromatin pattern, and absence of macronucleoli was seen only in benign cases. Assessment of background material was helpful in the differential diagnosis and classification. Necrosis was only found in high-grade cases. 相似文献
48.
49.
50.
Lucas Alves Moura Fernanda Vieira Ribeiro Talita Bianchi Aiello Eliana Ap. De Rezende Duek Enilson Antonio Sallum Francisco Humberto Nociti Junior 《Journal of biomaterials science. Polymer edition》2013,24(10):573-584
The aim of this pilot study was to assess the release of locally delivered doxycycline by poly (l-lactide-co-glycolide) (PLGA) microspheres in the periodontal pocket of patients with chronic periodontitis, treated by non-surgical periodontal therapy. Nineteen sites of non-adjacent teeth of four different patients were evaluated. Five milligram of PLGA microspheres loaded with 16 doxycycline hyclate (DOX) was administered per periodontal site. To quantify DOX released into the periodontal pocket, gingival crevicular fluid (GCF) was collected from the sites on days 2, 5, 7, 10, 15, and 20 after DOX application, and high-performance liquid chromatography was performed. Data were statistically assessed by ANOVA/Tukey test. At days 2, 5, and 7, the DOX concentration was stably sustained (23.33 ± 1.38, 23.4 ± 1.82, and 22.75 ± 1.33 μg/mL, respectively), with no significant differences over these assessment times (p > 0.05). At days 10 and 15, a tendency was observed toward a decrease in DOX concentration (21.74 ± 0.91 and 20.53 ± 4.88 μg/mL, respectively), but a significant decrease in GCF drug concentration (19.69 ± 4.70 μg/mL) was observed only on day 20. The DOX delivery system developed demonstrated a successful sustained release after local administration, as an adjunct to non-surgical periodontal therapy. 相似文献