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971.
Low colostrum intake at birth results in the failure of passive transfer (FPT) due to the inadequate ingestion of colostral immunoglobulins (Ig). FPT is associated with an increased risk of mortality and decreased health and longevity. Despite the known management practices associated with low FPT, it remains an important issue in the field. Neither a quantitative analysis of FPT consequences nor an assessment of its total cost are available. To address this point, a meta-analysis on the adjusted associations between FPT and its outcomes was first performed. Then, the total costs of FPT in European systems were calculated using a stochastic method with adjusted values as the input parameters. The adjusted risks (and 95% confidence intervals) for mortality, bovine respiratory disease, diarrhoea and overall morbidity in the case of FPT were 2.12 (1.43–3.13), 1.75 (1.50–2.03), 1.51 (1.05–2.17) and 1.91 (1.63–2.24), respectively. The mean (and 95% prediction interval) total costs per calf with FPT were estimated to be €60 (€10–109) and €80 (€20–139) for dairy and beef, respectively. As a result of the double-step stochastic method, the proposed economic estimation constitutes the first estimate available for FPT. The results are presented in a way that facilitates their use in the field and, with limited effort, combines the cost of each contributor to increase the applicability of the economic assessment to the situations farm-advisors may face. The present economic estimates are also an important tool to evaluate the profitability of measures that aim to improve colostrum intake and FPT prevention. 相似文献
972.
IL-1 signaling for IL-2 production in T cells involves a rise in phosphatidylserine synthesis 总被引:4,自引:0,他引:4
M Didier C Aussel C Pelassy M Fehlmann 《Journal of immunology (Baltimore, Md. : 1950)》1988,141(9):3078-3080
Activation of Jurkat T cells with anti-TCR, anti-CD3, anti-CD2, or PHA is accompanied by a strong inhibition of phosphatidylserine (PS) synthesis. The inhibition of the synthesis of this phospholipid could be partially reversed by IL-1. In Jurkat cells, IL-1 did not activate phosphodiesterases as demonstrated by the lack of change of inositol triphosphate and diacylglycerol levels as well as the lack of change in cytosolic Ca2+ concentration. Furthermore, IL-1 did not modify the intracellular level of cGMP and cAMP, suggesting that the observed rise of PS synthesis could play the role of mediator IL-1 action. As PS is a necessary cofactor for the activation of protein kinase C, our results suggest strongly that IL-1 modulate protein kinase C activity in the activated lymphocyte through its action on PS synthesis. 相似文献
973.
Covalent immobilization of pullulanase on alginate and study of its hydrolysis of pullulan 下载免费PDF全文
Ghina Ali Virginie Dulong Sarah N. Gasmi Christophe Rihouey Luc Picton Didier Le Cerf 《Biotechnology progress》2015,31(4):883-889
The immobilization of pullulanase from Klebsiella pneumoniae by grafting was investigated. Pullulanase was linked after activation of alginate via a covalent bond between the amine groups of the enzyme and the carboxylic acid groups of alginate. The immobilization yield was 60%. The activity of free pullulanase and immobilized pullulanase was followed by the quantification of reducing ends by colorimetric assay and the determination of the molar masses of the hydrolyzed pullulan by SEC/MALS/DRI. Compared to free pullulanase, the kinetics is largely slowed. The evolution of the weight average molar mass of pullulan leading to high production of shorter oligosaccharides during hydrolysis is not the same as that obtained with free enzyme. Immobilized pullulanase retained 75% and 30% of its initial activity after 24 h and 14 days of incubation at 60°C, respectively while free pullulanase lost its activity after 5 h of hydrolysis at the same temperature. The kinetic parameters of immobilized pullulanase were also investigated by isothermal titration calorimetry (ITC). The affinity of immobilized enzyme to its substrate was reduced compared to the free pullulanase due to steric hindrance and chemical links. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:883–889, 2015 相似文献
974.
Background
Airway wall remodeling in allergic asthma is reduced after treatment with humanized anti-IgE-antibodies. We reported earlier that purified IgE, without the presence of allergens, is sufficient to induce airway wall remodeling due to airway smooth muscle cell (ASMC) activity deposing extracellular matrix.Objective
We postulate that IgE contained in serum of allergic asthma patients, in the absence of allergens, stimulates ASMC remodeling activities and can be prevented by anti-IgE antibodies.Methods
Isolated human ASMC were exposed to serum obtained from: (i) healthy controls, or patients with (ii) allergic asthma, (iii) non-allergic asthma, and (iv) atopic non-asthma patients. Proliferation and the deposition of collagens and fibronectin were determined after 3 and 5 days.Results
Serum from patients with allergies significantly stimulated: (i) ASMC proliferation, (ii) deposition of collagen type-I (48 hours) and (iii) of fibronectin (24 hours). One hour pre-incubation with Omalizumab prevented these three effects of allergic serum, but had no significant effect on serum from healthy donors or non-allergic asthma patients. Interestingly, the addition of allergens did not further increase any of the IgE effects.Conclusion and Clinical Relevance
Our data provides experimental evidence that the beneficial effect of Omalizumab on airway wall remodeling and improved lung function may be due to its direct action on IgE bound ASMC. 相似文献975.
Marion Bougerol Frédéric Auradé Fran?ois M. Lambert Didier Le Ray Denis Combes Muriel Thoby-Brisson Frédéric Relaix Nicolas Pollet Hervé Tostivint 《PloS one》2015,10(2)
Xenopus is an excellent tetrapod model for studying normal and pathological motoneuron ontogeny due to its developmental morpho-physiological advantages. In mammals, the urotensin II-related peptide (UTS2B) gene is primarily expressed in motoneurons of the brainstem and the spinal cord. Here, we show that this expression pattern was conserved in Xenopus and established during the early embryonic development, starting at the early tailbud stage. In late tadpole stage, uts2b mRNA was detected both in the hindbrain and in the spinal cord. Spinal uts2b+ cells were identified as axial motoneurons. In adult, however, the uts2b expression was only detected in the hindbrain. We assessed the ability of the uts2b promoter to drive the expression of a fluorescent reporter in motoneurons by recombineering a green fluorescent protein (GFP) into a bacterial artificial chromosome (BAC) clone containing the entire X. tropicalis uts2b locus. After injection of this construction in one-cell stage embryos, a transient GFP expression was observed in the spinal cord of about a quarter of the resulting animals from the early tailbud stage and up to juveniles. The GFP expression pattern was globally consistent with that of the endogenous uts2b in the spinal cord but no fluorescence was observed in the brainstem. A combination of histological and electrophysiological approaches was employed to further characterize the GFP+ cells in the larvae. More than 98% of the GFP+ cells expressed choline acetyltransferase, while their projections were co-localized with α-bungarotoxin labeling. When tail myotomes were injected with rhodamine dextran amine crystals, numerous double-stained GFP+ cells were observed. In addition, intracellular electrophysiological recordings of GFP+ neurons revealed locomotion-related rhythmic discharge patterns during fictive swimming. Taken together our results provide evidence that uts2b is an appropriate driver to express reporter genes in larval motoneurons of the Xenopus spinal cord. 相似文献
976.
Ga?l Mourembou Florence Fenollar Jean Bernard Lekana-Douki Angelique Ndjoyi Mbiguino Sydney Maghendji Nzondo Pierre Blaise Matsiegui Rella Zoleko Manego Cyrille Herve Bile Ehounoud Fadi Bittar Didier Raoult Oleg Mediannikov 《PLoS neglected tropical diseases》2015,9(10)
Background
Like other tropical African countries, Gabon is afflicted by many parasitic diseases, including filariases such as loiasis and mansonellosis. This study aimed to assess the prevalence of these two filarial diseases in febrile and afebrile children using quantitative real-time PCR and standard PCR assays coupled with sequencing.Methodology/Principal Findings
DNA from blood specimens of 1,418 Gabonese children (1,258 febrile and 160 afebrile) were analyzed. Overall, filarial DNA was detected in 95 (6.7%) children, including 67 positive for M. perstans (4.7%), which was the most common. M. perstans was detected in 61/1,258 febrile children (4.8%) and 6/160 afebrile children (3.8%, P = 0.6). Its prevalence increased statistically with age: 3.5%, 7.7% and 10.6% in children aged ≤5, 6–10 and 11–15 years, respectively. M. perstans prevalence was significantly higher in Koulamoutou and Lastourville (12% and 10.5%, respectively) than in Franceville and Fougamou (2.6% and 2.4%, respectively). Loa loa was detected in seven febrile children including one co-infection with M. perstans. Finally, 21 filarial DNA positive were negative for M. perstans and Loa loa, but ITS sequencing could be performed for 12 and allowed the identification of a potential new species of Mansonella provisionally called “DEUX”. Mansonella sp. “DEUX” was detected only in febrile children.Conclusions/Significance
Further study should be performed to characterize Mansonella sp. “DEUX” and evaluate the clinical significance of mansonellosis in humans. 相似文献977.
Giorgia Urbinati Hafiz Muhammad Ali Quentin Rousseau Hubert Chapuis Didier Desma?le Patrick Couvreur Liliane Massaad-Massade 《PloS one》2015,10(5)
TMPRSS2-ERG junction oncogene is present in more than 50% of patients with prostate cancer and its expression is frequently associated with poor prognosis. Our aim is to achieve gene knockdown by siRNA TMPRSS2-ERG and then to assess the biological consequences of this inhibition. First, we designed siRNAs against the two TMPRSS2-ERG fusion variants (III and IV), most frequently identified in patients’ biopsies. Two of the five siRNAs tested were found to efficiently inhibit mRNA of both TMPRSS2-ERG variants and to decrease ERG protein expression. Microarray analysis further confirmed ERG inhibition by both siRNAs TMPRSS2-ERG and revealed one common down-regulated gene, ADRA2A, involved in cell proliferation and migration. The siRNA against TMPRSS2-ERG fusion variant IV showed the highest anti-proliferative effects: Significantly decreased cell viability, increased cleaved caspase-3 and inhibited a cluster of anti-apoptotic proteins. To propose a concrete therapeutic approach, siRNA TMPRSS2-ERG IV was conjugated to squalene, which can self-organize as nanoparticles in water. The nanoparticles of siRNA TMPRSS2-ERG-squalene injected intravenously in SCID mice reduced growth of VCaP xenografted tumours, inhibited oncoprotein expression and partially restored differentiation (decrease in Ki67). In conclusion, this study offers a new prospect of treatment for prostate cancer based on siRNA-squalene nanoparticles targeting TMPRSS2-ERG junction oncogene. 相似文献
978.
Nassima Benzoubir Charlotte Mussini Charlène Lejamtel Alexandre Dos Santos Claire Guillaume Christophe Desterke Didier Samuel Christian Bréchot Marie-Fran?oise Bourgeade Catherine Guettier 《PloS one》2015,10(6)
Background and Aims
The prognosis of hepatocellular carcinoma (HCC) is hampered by frequent tumour recurrence and metastases. Epithelial-Mesenchymal Transition (EMT) is now recognized as a key process in tumour invasion, metastasis and the generation of cancer initiating cells. The morphological identification of EMT in tumour samples from the expression of novel mesenchymal markers could provide relevant prognostic information and aid in understanding the metastatic process.Methods
The expression of Smooth Muscle Actins was studied using immunofluorescence and immunohistochemistry assays in cultured liver cells during an induced EMT process and in liver specimens from adult and paediatric HCC series.Results
We report here that in HCC cell lines treated with TGF-β and in HCC specimens, the expression of αSMA, a known mesenchymal marker of EMT, could never be detected. In addition, our in vitro studies identified the enteric form of SMA, γSMA, as being a marker of EMT. Moreover, this SMA isoform was expressed in 46% of 58 tumours from 42 adult HCC patients and in 90% of 16 tumours from 12 paediatric HCC patients. Interestingly, this expression was significantly correlated with poor tumour differentiation and progenitor cell features characterized by the expression of EpCAM and K19.Conclusion
Taken together, our results support the conclusion that γSMA expression in HCC is strongly correlated with the EMT process, HCC aggressiveness and the identification of cancer stem cells. This correlation suggests that γSMA represents a novel and powerful marker to predict HCC progression. 相似文献979.
We report exceptionally well-preserved plant remains ascribed to the extinct conifer Glenrosa J. Watson et H.L. Fisher emend. V. Srinivasan inside silica-rich nodules from the Cenomanian of the Font-de-Benon quarry, Charente-Maritime, western France. Remains are preserved in three dimensions and mainly consist of fragmented leafy axes. Pollen cones of this conifer are for the first time reported and in some cases remain connected to leafy stems. Histology of Glenrosa has not previously been observed; here, most of internal tissues and cells are well-preserved and allow us to describe a new species, Glenrosa carentonensis sp. nov., using propagation phase-contrast X-ray synchrotron microtomography, a non-destructive technique. Leafy axes consist of characteristic helically arranged leaves bearing stomatal crypts. Glenrosa carentonensis sp. nov. differs from the other described species in developing a phyllotaxy 8/21, claw-shaped leaves, a thicker cuticle, a higher number of papillae and stomata per crypt. Pollen cones consist of peltate, helically arranged microsporophylls, each of them bearing 6–7 pollen sacs. The new high resolution tomographic approach tested here allows virtual palaeohistology on plants included inside a dense rock to be made. Most tissues of Glenrosa carentonensis sp. nov. are described. Lithological and palaeontological data combined with xerophytic features of Glenrosa carentonensis sp. nov. suggest that this conifer has been adapted to survive in harsh and instable environments such as coastal area exposed to hot, dry conditions. 相似文献
980.
The Corynebacterium glutamicum mycothiol peroxidase is a reactive oxygen species‐scavenging enzyme that shows promiscuity in thiol redox control 下载免费PDF全文
Brandán Pedre Inge Van Molle Almudena F. Villadangos Khadija Wahni Didier Vertommen Lucía Turell Huriye Erdogan Luis M. Mateos Joris Messens 《Molecular microbiology》2015,96(6):1176-1191
Cysteine glutathione peroxidases (CysGPxs) control oxidative stress levels by reducing hydroperoxides at the expense of cysteine thiol (‐SH) oxidation, and the recovery of their peroxidatic activity is generally accomplished by thioredoxin (Trx). Corynebacterium glutamicum mycothiol peroxidase (Mpx) is a member of the CysGPx family. We discovered that its recycling is controlled by both the Trx and the mycothiol (MSH) pathway. After H2O2 reduction, a sulfenic acid (‐SOH) is formed on the peroxidatic cysteine (Cys36), which then reacts with the resolving cysteine (Cys79), forming an intramolecular disulfide (S‐S), which is reduced by Trx. Alternatively, the sulfenic acid reacts with MSH and forms a mixed disulfide. Mycoredoxin 1 (Mrx1) reduces the mixed disulfide, in which Mrx1 acts in combination with MSH and mycothiol disulfide reductase as a biological relevant monothiol reducing system. Remarkably, Trx can also take over the role of Mrx1 and reduce the Mpx‐MSH mixed disulfide using a dithiol mechanism. Furthermore, Mpx is important for cellular survival under H2O2 stress, and its gene expression is clearly induced upon H2O2 challenge. These findings add a new dimension to the redox control and the functioning of CysGPxs in general. 相似文献