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81.
?smet Berber Suat Ekin Peyami Battal Harun ?nlü M. Emre Erez 《Biological trace element research》2010,133(1):98-109
The present study investigated the levels of trace elements (Zn, Cu, Fe, Pb, and Cd), major elements (Ca and K), phytohormones
(trans-Zeatin [t-Z] and gibberellic acid [GA]), and sugars (sucrose and glucose) following inoculation with Pseudomonas syringae pv. tomato strain. The results of the trace elements analysis showed that Fe (in the first, fourth, eighth, and tenth study days), Cd
(in the fourth, eighth, and tenth study days), Cu (in the fourth and eighth study days), and Zn (in the eighth and tenth study
days) increased in bacterium-infected tomato plants, compared to healthy plants. The levels of Pb, Ca, and K did not meaningfully
determine a change after inoculation with pathogen. In this vein, the increase accumulation rates of Cu, Zn, and Fe in the
injured plants can be an important indicator for the plant defense processes towards pathogen attack. Furthermore, in the
first, fourth, eighth, and tenth study days, the glucose and sucrose contents crucially decreased in bacterium-infected plants
compared to the control groups. The lowest level of sucrose in bacterium-infected plants was observed on the first day. The
findings displayed that, when endogenous t-Z levels did not change after inoculation with virulent bacterium strain, there was a reduction in the first, fourth, eighth,
and tenth days in the level of GA when compared with the control group levels. Therefore, there may be a link between lower
GA level and enhancement in the expression of defense-related genes. The results of this study showed that there are complex
relationships among levels of sugar, trace element, and endogenous phytohormone in the regulation of defense mechanisms against
bacterial pathogen attacks. 相似文献
82.
Qaisar Abbas M. Emre Celebi Irene Fondón Garcı́a 《Biomedical signal processing and control》2013,8(2):204-214
Mass segmentation in mammograms is a challenging task due to problems such as low contrast, ill-defined, fuzzy or spiculated borders, and the presence of intensity inhomogeneities. These facts complicate the development of computer-aided diagnosis (CAD) systems to assist radiologists. In this paper, a novel mass segmentation algorithm for mammograms based on robust multiscale feature-fusion, and automatic estimation based maximum a posteriori (MAP) method is presented. The proposed segmentation technique consists of mainly four stages: a dynamic contrast improvement scheme applied to a selected region-of-interest (ROI), background-influence correction by template matching, detection of mass candidate points by prior and posterior probabilities based on robust multiscale feature-fusion, and final delineation of the mass region by a MAP scheme. This segmentation method is applied to 480 ROI masses that used ground truth from two radiologists. To compare its effectiveness with the state-of-the-art segmentation methods, three statistical metrics are employed. The experimental results indicate that the developed methods can reliably segment ill-defined or spiculated lesions when compared to other algorithms. Its integration in a CAD system may result in an improved aid to radiologists. 相似文献
83.
Romain Ballet Yalin Emre Stéphane Jemelin Mélanie Charmoy Fabienne Tacchini-Cottier Beat A. Imhof 《PLoS pathogens》2014,10(12)
The recruitment of dendritic cells to sites of infections and their migration to lymph nodes is fundamental for antigen processing and presentation to T cells. In the present study, we showed that antibody blockade of junctional adhesion molecule C (JAM-C) on endothelial cells removed JAM-C away from junctions and increased vascular permeability after L. major infection. This has multiple consequences on the output of the immune response. In resistant C57BL/6 and susceptible BALB/c mice, we found higher numbers of innate immune cells migrating from blood to the site of infection. The subsequent migration of dendritic cells (DCs) from the skin to the draining lymph node was also improved, thereby boosting the induction of the adaptive immune response. In C57BL/6 mice, JAM-C blockade after L. major injection led to an enhanced IFN-γ dominated T helper 1 (Th1) response with reduced skin lesions and parasite burden. Conversely, anti JAM-C treatment increased the IL-4-driven T helper 2 (Th2) response in BALB/c mice with disease exacerbation. Overall, our results show that JAM-C blockade can finely-tune the innate cell migration and accelerate the consequent immune response to L. major without changing the type of the T helper cell response. 相似文献
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Anti-inflammatuar and anti-oxidative effects of Nigella sativa L.: 18FDG-PET imaging of inflammation
Emre Entok Mehmet Cengiz Ustuner Cansu Ozbayer Neslihan Tekin Fahrettin Akyuz Berat Yangi Hulyam Kurt Irfan Degirmenci Hasan Veysi Gunes 《Molecular biology reports》2014,41(5):2827-2834
Inflammation has an important role in many diseases such as cystic fibrosis, allergies and cancer. The free radicals produced during inflammation, can induce gene mutations and posttranslational modifications of cancer related proteins. Nigella sativa L. (N. sativa) is herbaceous plant and commonly used as a natural food. It has many pharmacological effects including antibacterial, antifungal, antitumor, analgesic, antipyretic activity. The aim of this study was to investigate the anti-inflammatuar and anti-oxidant activity of N. sativa in acute inflammation. Thus we used the experimental lipopolysaccharides (LPS)-induced model. Intraperitoneal LPS 1 mg/kg was administered to groups. N. sativa (500 mg/kg) and essential oil (5 ml/kg) were given orally to treatment groups, after 24-h of intraperitoneal LPS-injection. To determine the lung inflammation, 18F-fluoro-deoxy-d-glucose (0.8 ml/kg) was administrated under the anesthesia before the 1 h of PET-scanning. After the FDG-PET, samples were collected. Lung and liver 18F-FDG-uptake was calculated. Serum AST, ALT, LDH and hcCRP levels were determined and liver, lung and erythrocyte SOD, MDA and CAT levels were measured. Liver and lung NO and DNA fragmentation levels were determined. MDA levels were decreased in treated inflammation groups whereas increased in untreated inflammation group. SOD and CAT activities in untreated inflammation group were significantly lower. According to the control group, increased AST and ALT levels were found in untreated inflammation group. 18F-FDG uptake of inflammation groups were increased when compare the control group. We found increased 18F-FDG uptake, DNA fragmentation and NO levels in LPS-induced inflammation groups. We conclude that, in LPS-induced inflammation, N. sativa have therapeutic and anti-oxidant effects. 相似文献
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Tepeli E Caner V Büyükpınarbaşılı N Çetin GO Düzcan F Elmas L Bağcı G 《Molecular biology reports》2012,39(1):335-341
Excision Repair Cross-Complementing Group 1 (ERCC1) is an important DNA repair gene, playing critical role in nucleotide excision repair pathway and having a significant influence
on genomic instability. Some studies support that ERCC1 might be a potential predictive and prognostic marker in non-small cell lung cancer (NSCLC). ERCC1 has also been shown to be a promising biomarker in NSCLC treated with a cisplatin-based regimen. Therefore, the determination
of ERCC1 expression at DNA, mRNA and protein level in different stages of NSCLC is still an important topic in the cancer.
Ninety-one formalin-fixed paraffin-embedded tumor samples histopathologically diagnosed as NSCLC were examined in this study.
ERCC1 expression at protein level were scored by immunohistochemistry. The gene amplification and mRNA expression levels for
ERCC1 were determined by real-time quantitative PCR. There was complete concordance among the three methods in 39 tumor samples
(42.9%). A strong correlation was found between DNA amplification and mRNA expression (r = 0.662) while there was no correlation between mRNA and protein assessment for ERCC1 expression (r = −0.013). ERCC1 expression at mRNA and DNA level (63.1 and 84.2%, respectively) in tumors at stage III was higher than at
the other stages. In contrast, the protein expression at stage II and III (56.6 and 52.6%, respectively) of NSCLC was lower
than that of tumors with stage I NSCLC. These results show that the mechanism by which ERCC1 expression might play a role
in tumor behavior. This study was also confirmed that the appropriate validation and qualification in methods used for ERCC1
status were needed before its clinical application and implementation. 相似文献