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151.
The schistosomal parasite plays a critical role in the development of malignant lesions in different organs. The pathogenesis of cancer is currently under intense investigation to identify reliable prognostic indices for disease detection. The objective of this paper is to evaluate certain biochemical parameters as diagnostic tools to efficiently differentiate between colonic carcinoma and colonic carcinoma associated with schistosomal infection among Egyptian patients. The parameters under investigation are interleukin 2 (IL-2), tumour necrosis factor alpha (TNF-α), carcinoembryonic antigen (CEA) levels, tissue telomerase, pyruvate kinase (PK), glucose-6-phosphate dehydrogenase (G-6-PD) and lactate dehydrogenase (LDH) enzyme activities. The results revealed a significant elevation in the level of the tumour markers IL-2, TNF-α and CEA as well as the activities of LDH, telomerase and G-6-PD among non-bilharzial and bilharzial colonic cancer groups, with a more potent effect in bilharzial infection-associated colonic cancer. A significant inhibition in PK activity was recorded in the same manner as compared to normal tissues. The efficacy of this biomarker was also evaluated through detecting sensitivity, specificity, negative and positive predictive values. In conclusion, schistosomal colonic carcinoma patients displayed more drastic changes in all parameters under investigation. The combination of the selected parameters succeeded in serving as biomarkers to differentiate between the two malignant types. 相似文献
152.
The effects of pH value and presence of serum in an incubation medium on photosensitizer drug cellular uptake in MCF7 cancer
cells have been investigated. The results showed that the presence of serum in an incubation medium reduced the drug cellular
uptake at all pH values. It has been found that decreasing on pH values of the incubation medium increased the cellular uptake
of the drug, demonstrating selective uptake of the sensitizer. The HepG2 liver cancer cells exhibited more drug cellular uptake
than CCD-18CO normal colon cells, which assessed the selectivity uptake of photosensitizer on cancerous cells. The concentration
of photosensitizer measured in 106 cells showed a good correlation to the incubation time. Fluorescence and absorption spectroscopy been have used to examine
the cells. 相似文献
153.
154.
Chtourou Y Trabelsi K Fetoui H Mkannez G Kallel H Zeghal N 《Neurochemical research》2011,36(8):1546-1557
Manganese (Mn) is an essential trace element required for ubiquitous enzymatic reactions. Chronic overexposure to this metal
may promote potent neurotoxic effects. The mechanism of Mn toxicity is not well established, but several studies indicate
that oxidative stress play major roles in the Mn-induced neurodegenerative processes. Silymarin (SIL) has antioxidant properties
and stabilizes intracellular antioxidant defense systems. The aim of this study was to evaluate the toxic effects of MnCl2 on the mouse neuroblastoma cell lines (Neuro-2A), to characterize the toxic mechanism associated with Mn exposure and to
investigate whether SIL could efficiently protect against neurotoxicity induced by Mn. A significant increase in LDH release
activity was observed in Neuro-2A cells associated with a significant decrease in cellular viability upon 24 h exposure to
MnCl2 at concentrations of 200 and 800 μM (P < 0.05) when compared with control unexposed cells. In addition, exposure cells to MnCl2 (200 and 800 μM), increases oxidant biomarkers and alters enzymatic and non enzymatic antioxidant systems. SIL treatment
significantly reduced the levels of LDH, nitric oxide, reactive oxygen species and the oxidants/antioxidants balance in Neuro-2A
cells as compared to Mn-exposed cells. These results suggested that silymarin is a powerful antioxidant through a mechanism
related to its antioxidant activity, able to interfere with radical-mediated cell death. SIL may be useful in diseases known
to be aggravated by reactive oxygen species and in the development of novel treatments for neurodegenerative disorders such
as Alzheimer or Parkinson diseases. 相似文献
155.
Ghassen Abid Yordan Muhovski Jean-Marie Jacquemin Dominique Mingeot Khaled Sassi André Toussaint Jean-Pierre Baudoin 《Plant Cell, Tissue and Organ Culture》2011,107(2):341-353
Two genotypes of common bean (Phaseolus vulgaris L.) were studied to determine the structural cause of seed abortion in this species. In the non-abortive control (wild-type,
cultivar BAT93), the histological analysis revealed a classical pattern of seed development and showed coordinated differentiation
of the embryo proper, suspensor, endosperm tissue and seed coat. In contrast, the ethyl methanesulfonate (EMS) mutant (cultivar
BAT93) showed disruption in the normal seed development leading to embryo abortion. Aborted embryos from these degenerate
seeds showed abnormalities in suspensor and cotyledons at the globular, heart, torpedo and cotyledon stages. Exploring the
feasibility of incorporating the available online bioinformatics databases, we identified 22 genes revealing high homology
with genes involved in Arabidopsis
thaliana embryo development and expressed in common bean immature seeds. The expression patterns of these genes were confirmed by
RT–PCR. All genes were highly expressed in seed tissues. To study the expression profiles of isolated genes during Phaseolus embryogenesis, six selected genes were examined by quantitative RT–PCR analysis on the developing embryos of wild-type and
EMS mutant plants. All selected genes were expressed differentially at different stages of embryo development. These results
could help to improve understanding of the mechanism of common bean embryogenesis. 相似文献
156.
157.
Ghada Baraket Khaled Chatti Olfa Saddoud Ahmed Ben Abdelkarim Messaoud Mars Mokhtar Trifi Amel Salhi Hannachi 《Plant Molecular Biology Reporter》2011,29(1):171-184
This study characterises the genetic variability of fig, Ficus carica L., using simple sequence repeat (SSR) and amplified fragment length polymorphism (AFLP) markers. It compares the efficiency
and utility of the two techniques in detecting variation and establishing genetic relationships among Tunisian fig cultivars.
Our results show that using both marker systems, the Tunisian fig germ plasm is characterised by having a large genetic diversity
at the deoxyribonucleic acid level, as most of AFLP bands were detected and all SSR markers were polymorphic. In fact, 351
(342 polymorphic) and 57 (57 polymorphic) bands were detected using AFLP and SSR primers, respectively. SSR markers were the
most polymorphic with an average polymorphic information content value of 0.94, while AFLP markers showed the highest effective
multiplex ratio (56.9) and marker index (45.2). The effective marker index was recorded highest (4.19) for AFLP markers and
lowest (0.70) for the SSR ones. Our results demonstrate that (1) independent as well as combined analyses of cluster analyses
of SSR and AFLP fragments showed that cultivars are clustered independently from their geographical origin, horticultural
classifications and tree sex; (2) the analysis of molecular variance allowed the partitioning of genetic variation within
and among fig groups and showed greater variation within groups and (3) AFLP and SSR markers datasets showed positive correlation.
This study suggests the SSR and AFLP markers are suitable for diversity analysis and cultivars fingerprinting. An understanding
of the genetic diversity and population structure of F. carica in Tunisia can also provide insight into the conservation and management of this species. 相似文献
158.
Sarra Migaw Taoufik Ghrairi Yanath Belguesmia Yvan Choiset Jean-Marc Berjeaud Jean-Marc Chobert Khaled Hani Thomas Haertlé 《World journal of microbiology & biotechnology》2014,30(4):1207-1217
Nine lactic acid bacteria strains showing bacteriocin-like activity were isolated from various fresh fish viscera. The following species were identified based on 16S rDNA sequences: Enterococcus durans (7 isolates), Lactococcus lactis (1) and Enterococcus faecium (1). These strains were active against Listeria innocua and other LAB. Random amplified polymorphic DNA analyses showed four major patterns for the E. durans species. PCR analyses revealed a nisin gene in the genome of the Lc. lactis strain. Genes coding enterocins A, B and P were found in the genome of the E. faecium isolate. Enterocins A and B genes were also present in the genome of E. durans GM19. Hence, this is the first report describing E. durans strains producing enterocins A and B. Electrospray ionization mass spectrometry revealed that the purified bacteriocin produced by the E. durans GMT18 strain had an exact molecular mass of 6,316.89 Da. This bacteriocin was designated as durancin GMT18. Edman sequencing failed to proceed; suggesting that durancin GTM18 may contain terminal lanthionine residues. Overall, the results obtained revealed the presence of a variety of enterococci in Mediterranean fish viscera, as evidenced by their genetic profiles and abilities to produce different bacteriocins. These strains could be useful for food biopreservation or as probiotics. 相似文献
159.
Adrian Egli Deanna M. Santer Daire O'Shea Khaled Barakat Mohammedyaseen Syedbasha Madeleine Vollmer Aliyah Baluch Rakesh Bhat Jody Groenendyk Michael A. Joyce Luiz F. Lisboa Brad S. Thomas Manuel Battegay Nina Khanna Thomas Mueller D. Lorne J. Tyrrell Michael Houghton Atul Humar Deepali Kumar 《PLoS pathogens》2014,10(12)
Influenza is a major cause of morbidity and mortality in immunosuppressed persons, and vaccination often confers insufficient protection. IL-28B, a member of the interferon (IFN)-λ family, has variable expression due to single nucleotide polymorphisms (SNPs). While type-I IFNs are well known to modulate adaptive immunity, the impact of IL-28B on B- and T-cell vaccine responses is unclear. Here we demonstrate that the presence of the IL-28B TG/GG genotype (rs8099917, minor-allele) was associated with increased seroconversion following influenza vaccination (OR 1.99 p = 0.038). Also, influenza A (H1N1)-stimulated T- and B-cells from minor-allele carriers showed increased IL-4 production (4-fold) and HLA-DR expression, respectively. In vitro, recombinant IL-28B increased Th1-cytokines (e.g. IFN-γ), and suppressed Th2-cytokines (e.g. IL-4, IL-5, and IL-13), H1N1-stimulated B-cell proliferation (reduced 70%), and IgG-production (reduced>70%). Since IL-28B inhibited B-cell responses, we designed antagonistic peptides to block the IL-28 receptor α-subunit (IL28RA). In vitro, these peptides significantly suppressed binding of IFN-λs to IL28RA, increased H1N1-stimulated B-cell activation and IgG-production in samples from healthy volunteers (2-fold) and from transplant patients previously unresponsive to vaccination (1.4-fold). Together, these findings identify IL-28B as a key regulator of the Th1/Th2 balance during influenza vaccination. Blockade of IL28RA offers a novel strategy to augment vaccine responses. 相似文献
160.
Khaled Abdel-Aziz Bhavana S. Solanky Marios C. Yiannakas Daniel R. Altmann Claudia A. M. Wheeler-Kingshott Alan J. Thompson Olga Ciccarelli 《PloS one》2014,9(10)
Magnetic resonance spectroscopy (MRS) studies have previously described metabolite changes associated with aging of the healthy brain and provided insights into normal brain aging that can assist us in differentiating age-related changes from those associated with neurological disease. The present study investigates whether age-related changes in metabolite concentrations occur in the healthy cervical spinal cord. 25 healthy volunteers, aged 23–65 years, underwent conventional imaging and single-voxel MRS of the upper cervical cord using an optimised point resolved spectroscopy sequence on a 3T Achieva system. Metabolite concentrations normalised to unsuppressed water were quantified using LCModel and associations between age and spinal cord metabolite concentrations were examined using multiple regressions. A linear decline in total N-Acetyl-aspartate concentration (0.049 mmol/L lower per additional year of age, p = 0.010) and Glutamate-Glutamine concentration (0.054 mmol/L lower per additional year of age, p = 0.002) was seen within our sample age range, starting in the early twenties. The findings suggest that neuroaxonal loss and/or metabolic neuronal dysfunction, and decline in glutamate-glutamine neurotransmitter pool progress with aging. 相似文献