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41.
Qin W Hu J Guo M Xu J Li J Yao G Zhou X Jiang H Zhang P Shen L Wan D Gu J 《Biochemical and biophysical research communications》2003,308(2):379-385
The execution phase of apoptosis is characterized by marked changes in cell morphology that include contraction and membrane blebbing. Little is known about the mechanisms underlying this process. We report here the identification of a novel member of BNIPL family, designated Bcl-2/adenovirus E1B 19kDa interacting protein 2 like-2 (BNIPL-2), which interacts with Bcl-2 and Cdc42GAP. We found that the human BNIPL-2 shares homology to human BNIP-2 and also possesses a BNIP-2 and Cdc42GAP homology (BCH) domain. Deletion experiments indicated that the BCH domain of BNIPL-2 is critical for its interactions with the Bcl-2 and Cdc42GAP and also for its cell death-inducing function. Our data showed that BNIPL-2 may be a linker protein located at the front end of Bcl-2 pathway for DNA fragmentation and Cdc42 signaling for morphological changes during apoptosis. We propose that BNIPL-2 protein may play an important role in regulation of both pathways for DNA fragmentation and for formation of membrane blebs in apoptotic cells. 相似文献
42.
Improved paclitaxel accumulation in cell suspension cultures of Taxus chinensis by brassinolide 总被引:3,自引:0,他引:3
When brassinolide was added at 17 ng l–1 to Taxus chinensis cell suspension cultures, the paclitaxel content was increased by over 100% to 580 g g–1 dry weight. Brassinolide may therefore be a novel regulator of paclitaxel biosynthesis. 相似文献
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Kim Y. C. Fung Bruce Tabor Michael J. Buckley Ilka K. Priebe Leanne Purins Celine Pompeia Gemma V. Brierley Trevor Lockett Peter Gibbs Jeanne Tie Paul McMurrick James Moore Andrew Ruszkiewicz Edouard Nice Timothy E. Adams Antony Burgess Leah J. Cosgrove 《PloS one》2015,10(3)
Background
The majority of colorectal cancer (CRC) cases are preventable by early detection and removal of precancerous polyps. Even though CRC is the second most common internal cancer in Australia, only 30 per cent of the population considered to have risk factors participate in stool-based test screening programs. Evidence indicates a robust, blood-based, diagnostic assay would increase screening compliance. A number of potential diagnostic blood-based protein biomarkers for CRC have been reported, but all lack sensitivity or specificity for use as a stand-alone diagnostic. The aim of this study was to identify and validate a panel of protein-based biomarkers in independent cohorts that could be translated to a reliable, non-invasive blood-based screening test.Principal Findings
In two independent cohorts (n = 145 and n = 197), we evaluated seven single biomarkers in serum of CRC patients and age/gender matched controls that showed a significant difference between controls and CRC, but individually lack the sensitivity for diagnostic application. Using logistic regression strategies, we identified a panel of three biomarkers that discriminated between controls and CRC with 73% sensitivity at 95% specificity, when applied to either of the two cohorts. This panel comprised of Insulin like growth factor binding protein 2 (IGFBP2), Dickkopf-3 (DKK3), and Pyruvate kinase M2(PKM2).Conclusions
Due to the heterogeneous nature of CRC, a single biomarker is unlikely to have sufficient sensitivity or specificity for use as a stand-alone diagnostic screening test and a panel of markers may be more effective. We have identified a 3 biomarker panel that has higher sensitivity and specificity for early stage (Stage I and -II) disease than the faecal occult blood test, raising the possibility for its use as a non-invasive blood diagnostic or screening test. 相似文献45.
Gongguan Liu Jinjun Xu Hui Wu Donglei Sun Xiquan Zhang Xiaoping Zhu Stefan Magez Meiqing Shi 《PLoS pathogens》2015,11(7)
African trypanosomes are extracellular protozoan parasites causing a chronic debilitating disease associated with a persistent inflammatory response. Maintaining the balance of the inflammatory response via downregulation of activation of M1-type myeloid cells was previously shown to be crucial to allow prolonged survival. Here we demonstrate that infection with African trypanosomes of IL-27 receptor-deficient (IL-27R-/-) mice results in severe liver immunopathology and dramatically reduced survival as compared to wild-type mice. This coincides with the development of an exacerbated Th1-mediated immune response with overactivation of CD4+ T cells and strongly enhanced production of inflammatory cytokines including IFN-γ. What is important is that IL-10 production was not impaired in infected IL-27R-/- mice. Depletion of CD4+ T cells in infected IL-27R-/- mice resulted in a dramatically reduced production of IFN-γ, preventing the early mortality of infected IL-27R-/- mice. This was accompanied by a significantly reduced inflammatory response and a major amelioration of liver pathology. These results could be mimicked by treating IL-27R-/- mice with a neutralizing anti-IFN-γ antibody. Thus, our data identify IL-27 signaling as a novel pathway to prevent early mortality via inhibiting hyperactivation of CD4+ Th1 cells and their excessive secretion of IFN-γ during infection with African trypanosomes. These data are the first to demonstrate the essential role of IL-27 signaling in regulating immune responses to extracellular protozoan infections. 相似文献
46.
Yu Hua Tong Tie Pei Zhu Ze Lin Zhao Hai Jing Zhan Fang Zheng Jiang Heng Li Lian 《PloS one》2015,10(12)
Objectives
In this study, we develop a microdensitometry method using full width at half maximum (FWHM) analysis of the retinal vascular structure in a spectral-domain optical coherence tomography (SD-OCT) image and present the application of this method in the morphometry of arteriolar changes during hypertension.Methods
Two raters using manual and FWHM methods measured retinal vessel outer and lumen diameters in SD-OCT images. Inter-rater reproducibility was measured using coefficients of variation (CV), intraclass correlation coefficient and a Bland-Altman plot. OCT images from forty-three eyes of 43 hypertensive patients and 40 eyes of 40 controls were analyzed using an FWHM approach; wall thickness, wall cross-sectional area (WCSA) and wall to lumen ratio (WLR) were subsequently calculated.Results
Mean difference in inter-rater agreement ranged from -2.713 to 2.658 μm when using a manual method, and ranged from -0.008 to 0.131 μm when using a FWHM approach. The inter-rater CVs were significantly less for the FWHM approach versus the manual method (P < 0.05). Compared with controls, the wall thickness, WCSA and WLR of retinal arterioles were increased in the hypertensive patients, particular in diabetic hypertensive patients.Conclusions
The microdensitometry method using a FWHM algorithm markedly improved inter-rater reproducibility of arteriolar morphometric analysis, and SD-OCT may represent a promising noninvasive method for in vivo arteriolar morphometry. 相似文献47.
Lei-Lei Chen Tie Bin Zhu Hang Yin Jun Huang Lian Sheng Wang Ke Jiang Cao Zhi Jian Yang 《Molecular biology reports》2010,37(7):3067-3072
Endothelial nitric oxide synthase (eNOS) and nitric oxide (NO) may play an important role in attenuating cardiac remodeling
and apoptosis after myocardial infarction. However, the anti-inflammation effects of eNOS in infarcted myocardium and the
role of MAPK signaling in eNOS/NO mediated cardiac remodeling have not yet been elucidated. Adenovirus carrying Human eNOS
gene was delivered locally into heart 4 days prior to induction of myocardial infarction (MI) by left anterior descending
coronary artery ligation. Monocyte/macrophage infiltration was detected by ED-1 immunohistochemistry. Western blot was employed
to examine the activation of MAPK. eNOS gene transfer significantly reduced myocardial infarct size and improved cardiac contractility
as well as left ventricle (LV) diastolic function at 7 days after MI. In addition, eNOS gene transfer decreased monocyte/macrophage
infiltration in the infarct region of the heart. Phosphorylation of MAPK after MI were also dramatically reduced by eNOS gene
transfer. All the protective effects of eNOS were blocked by N(ω)-nitro-l-arginine methyl ester (L-NAME) administration, indicating a NO-mediated event. These results demonstrate that the eNOS/NO
system provides cardiac protection after MI injury through inhibition of inflammation and suppression of MAPK signaling. 相似文献
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