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141.
Theoni Margaritopoulou Loukia Roka Efi Alexopoulou Myrsini Christou Stamatis Rigas Kosmas Haralampidis Dimitra Milioni 《Molecular biotechnology》2016,58(3):149-158
New crops are gradually establishing along with cultivation systems to reduce reliance on depleting fossil fuel reserves and sustain better adaptation to climate change. These biological assets could be efficiently exploited as bioenergy feedstocks. Bioenergy crops are versatile renewable sources with the potential to alternatively contribute on a daily basis towards the coverage of modern society’s energy demands. Biotechnology may facilitate the breeding of elite energy crop genotypes, better suited for bio-processing and subsequent use that will improve efficiency, further reduce costs, and enhance the environmental benefits of biofuels. Innovative molecular techniques may improve a broad range of important features including biomass yield, product quality and resistance to biotic factors like pests or microbial diseases or environmental cues such as drought, salinity, freezing injury or heat shock. The current review intends to assess the capacity of biotechnological applications to develop a beneficial bioenergy pipeline extending from feedstock development to sustainable biofuel production and provide examples of the current state of the art on future energy crops. 相似文献
142.
Triantafilou M Gamper FG Lepper PM Mouratis MA Schumann C Harokopakis E Schifferle RE Hajishengallis G Triantafilou K 《Cellular microbiology》2007,9(8):2030-2039
Infection with bacteria such as Chlamydia pneumonia, Helicobacter pylori or Porphyromonas gingivalis may be triggering the secretion of inflammatory cytokines that leads to atherogenesis. The mechanisms by which the innate immune recognition of these pathogens could lead to atherosclerosis remain unclear. In this study, using human vascular endothelial cells or HEK-293 cells engineered to express pattern-recognition receptors (PRRs), we set out to determine Toll-like receptors (TLRs) and functionally associated PRRs involved in the innate recognition of and response to lipopolysaccharide (LPS) from H. pylori or P. gingivalis. Using siRNA interference or recombinant expression of cooperating PRRs, we show that H. pylori and P. gingivalis LPS-induced cell activation is mediated through TLR2. Human vascular endothelial cell activation was found to be lipid raft-dependent and to require the formation of heterotypic receptor complexes comprising of TLR2, TLR1, CD36 and CD11b/CD18. In addition, we report that LPS from these bacterial strains are able to antagonize TLR4. This antagonistic activity of H. pylori or P. gingivalis LPS, as well as their TLR2 activation capability may be associated with their ability to contribute to atherosclerosis. 相似文献
143.
Marios S Neofytou Vasilis Tanos Marios S Pattichis Constantinos S Pattichis Efthyvoulos C Kyriacou Dimitris D Koutsouris 《Biomedical engineering online》2007,6(1):44
Background
In the development of tissue classification methods, classifiers rely on significant differences between texture features extracted from normal and abnormal regions. Yet, significant differences can arise due to variations in the image acquisition method. For endoscopic imaging of the endometrium, we propose a standardized image acquisition protocol to eliminate significant statistical differences due to variations in: (i) the distance from the tissue (panoramic vs close up), (ii) difference in viewing angles and (iii) color correction. 相似文献144.
Comparative analysis of peripheral and localised cytokine secretion in glioblastoma patients 总被引:2,自引:0,他引:2
Zisakis A Piperi C Themistocleous MS Korkolopoulou P Boviatsis EI Sakas DE Patsouris E Lea RW Kalofoutis A 《Cytokine》2007,39(2):99-105
BACKGROUND: Malignant gliomas are the most common primary brain tumours of both children and adults. The unique aspects of their biology and anatomic site render them refractory to conventional therapeutic strategies such as surgery and chemotherapy. Significant attention has been given, recently, to immunotherapy which, although promising in preclinical studies, has not yet enhanced the survival of patients with glioblastomas. METHODS: To further understand the immunobiology of glioblastomas in clinical settings, we examined the secretion of four main cytokines in the peripheral blood and in primary cell cultures of 33 human glioblastoma patients. An ELISPOT methodology was used for the first time to examine Th1, and Th2 cytokine secretion from both peripheral lymphocytes and glioma tumour cells. RESULTS: Th1 cytokines (tumour necrosis factor (TNF-alpha), interferon (IFN-gamma) were markedly reduced compared to control levels (P=0.01 and P<0.001, respectively), whereas in contrast, Th2 (interleukin (IL)-4 and IL-10) were strongly expressed in both peripheral lymphocytes and glioma cell cultures (P=0.05 and P<0.001, respectively). CONCLUSION: This pattern indicates an 'immunosuppressive status' in glioblastomas which is related to their origination and the evasion of glioma cells from immune surveillance and could account for the failure of immunotherapy in such tumours. Furthermore, ELISPOT methodology can be used for monitoring of cytokine secretion from tumour cells, in addition to the well-established peripheral cytokine secretion. 相似文献
145.
Argyris Tzouvelekis Vassilis Aidinis Vagelis Harokopos Andreas Karameris George Zacharis Dimitrios Mikroulis Fotios Konstantinou Paschalis Steiropoulos Ioannis Sotiriou Marios Froudarakis Ioannis Pneumatikos Rodoula Tringidou Demosthenes Bouros 《Respiratory research》2009,10(1):14
Background
Recent evidence has underscored the role of hypoxia and angiogenesis in the pathogenesis of idiopathic fibrotic lung disease. Inhibitor of growth family member 4 (ING4) has recently attracted much attention as a tumor suppressor gene, due to its ability to inhibit cancer cell proliferation, migration and angiogenesis. The aim of our study was to investigate the role of ING4 in the pathogenesis of pulmonary fibrosis both in the bleomycin (BLM)-model and in two different types of human pulmonary fibrosis, including idiopathic pulmonary fibrosis (IPF) and cryptogenic organizing pneumonia (COP).Methods
Experimental model of pulmonary fibrosis was induced by a single tail vein injection of bleomycin in 6- to 8-wk-old C57BL/6mice. Tissue microarrays coupled with qRT-PCR and immunohistochemistry were applied in whole lung samples and paraffin-embedded tissue sections of 30 patients with IPF, 20 with COP and 20 control subjects.Results
A gradual decline of ING4 expression in both mRNA and protein levels was reported in the BLM-model. ING4 was also found down-regulated in IPF patients compared to COP and control subjects. Immunolocalization analyses revealed increased expression in areas of normal epithelium and in alveolar epithelium surrounding Masson bodies, in COP lung, whereas showed no expression within areas of active fibrosis within IPF and COP lung. In addition, ING4 expression levels were negatively correlated with pulmonary function parameters in IPF patients.Conclusion
Our data suggest a potential role for ING4 in lung fibrogenesis. ING4 down-regulation may facilitate aberrant vascular remodelling and fibroblast proliferation and migration leading to progressive disease. 相似文献146.
Dopaminergic activity is expected to be altered in patients with Huntington’s disease (HD) and be related to factors like
duration and severity of illness or patients’ specific symptomatology like dementia, depression, or psychotic features. We
assessed plasma homovanillic acid (pHVA) and plasma prolactin (pPRL), two correlates of dopaminergic activity, in 116 subjects
with CAG repeats expansion in the HD gene, 26 presymptomatic (18 females) and 90 with overt symptomatology (43 females). Patients
were evaluated using the Unified HD Rating Scale and the Total Functional Capacity Scale. Presence of dementia, depression,
and psychotic features were also assessed. The age range of the patients was 22–83 years, duration of illness from 0.5 to
27 years, and CAG repeat number from 34 to 66. A group of 60 age and sex matched healthy subjects served as control group.
Plasma PRL in subjects at risk and in neuroleptic-free patients, evaluated separately for males and females, did not differ
from controls. Plasma HVA levels did not differ from controls in the group of presymptomatic subjects, but were significantly
higher in the patients group. This increase was positively associated mainly with severity of illness and functional capacity
of the patients, and not with presence of depression or dementia. Plasma HVA levels may be proven to be a peripheral index
of disease progression. Reducing dopaminergic activity may have not only symptomatic, but also neuroprotective effects in
HD. 相似文献
147.
den Besten HM Mataragas M Moezelaar R Abee T Zwietering MH 《Applied and environmental microbiology》2006,72(9):5884-5894
The food-borne pathogen Bacillus cereus can acquire enhanced thermal resistance through multiple mechanisms. Two Bacillus cereus strains, ATCC 10987 and ATCC 14579, were used to quantify the effects of salt stress and physiological state on thermotolerance. Cultures were exposed to increasing concentrations of sodium chloride for 30 min, after which their thermotolerance was assessed at 50 degrees C. Linear and nonlinear microbial survival models, which cover a wide range of known inactivation curvatures for vegetative cells, were fitted to the inactivation data and evaluated. Based on statistical indices and model characteristics, biphasic models with a shoulder were selected and used for quantification. Each model parameter reflected a survival characteristic, and both models were flexible, allowing a reduction of parameters when certain phenomena were not present. Both strains showed enhanced thermotolerance after preexposure to (non)lethal salt stress conditions in the exponential phase. The maximum adaptive stress response due to salt preexposure demonstrated for exponential-phase cells was comparable to the effect of physiological state on thermotolerance in both strains. However, the adaptive salt stress response was less pronounced for transition- and stationary-phase cells. The distinct tailing of strain ATCC 10987 was attributed to the presence of a subpopulation of spores. The existence of a stable heat-resistant subpopulation of vegetative cells could not be demonstrated for either of the strains. Quantification of the adaptive stress response might be instrumental in understanding adaptation mechanisms and will allow the food industry to develop more accurate and reliable stress-integrated predictive modeling to optimize minimal processing conditions. 相似文献
148.
149.
Beauchamp KA El-Matbouli M Gay M Georgiadis MP Nehring RB Hedrick RP 《Journal of invertebrate pathology》2006,91(1):1-8
The competitive interactions between susceptible and resistant Tubifex tubifex (Oligochaeta: Tubificidae) exposed to Myxobolus cerebralis (Myxozoa: Myxobolidae) infections were investigated in two laboratory trials. Competition was assessed by the total parasite production over the course of the trials in mixed and pure cultures of M. cerebralis exposed worms, and by the genetic analyses of worms from the control and experimental groups at the beginning and end of the experiments. Mixed cultures of resistant and susceptible worms showed a 70% reduction in production of parasites released when compared with pure cultures of susceptible worms. In studies with laboratory and field-collected oligochaetes the mixed cultures at the end of the cohabitation experiments were dominated by resistant Tubifex from lineage V (HB strain) this strain of Tubifex has a competitive advantage over worms from other lineages. The results of this study suggest that certain species of Tubifex may be dead-end hosts to M. cerebralis by absorbing or inactivating the parasite and may also show greater survival compared to susceptible oligochaetes in certain whirling disease enzootic habitats. 相似文献
150.