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A molecular beacon, bead-based assay for the detection of nucleic acids by flow cytometry 总被引:3,自引:1,他引:2
Horejsh D Martini F Poccia F Ippolito G Di Caro A Capobianchi MR 《Nucleic acids research》2005,33(2):e13
Molecular beacons are dual-labelled probes that are typically used in real-time PCR assays, but have also been conjugated with solid matrices for use in microarrays or biosensors. We have developed a fluid array system using microsphere-conjugated molecular beacons and the flow cytometer for the specific, multiplexed detection of unlabelled nucleic acids in solution. For this array system, molecular beacons were conjugated with microspheres using a biotin-streptavidin linkage. A bridged conjugation method using streptavidin increased the signal-to-noise ratio, allowing for further discrimination of target quantitation. Using beads of different sizes and molecular beacons in two fluorophore colours, synthetic nucleic acid control sequences were specifically detected for three respiratory pathogens, including the SARS coronavirus in proof-of-concept experiments. Considering that routine flow cytometers are able to detect up to four fluorescent channels, this novel assay may allow for the specific multiplex detection of a nucleic acid panel in a single tube. 相似文献
3.
Polito Francesca Famà Fausto Oteri Rosaria Raffa Giovanni Vita Gianluca Conti Alfredo Daniele Sacco Macaione Vincenzo Passalacqua Marcello Cardali Salvatore Di Giorgio Rosa Maria Gioffrè Maria Angileri Flavio F. Germanò Antonino Aguennouz M’Hammed 《Molecular biology reports》2020,47(4):2941-2949
Molecular Biology Reports - TBI is the main cause of death and disability in individuals aged 1–45 in Western countries. One of the main challenges of TBI at present is the lack of specific... 相似文献
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Umberto Raucci Rossella Rossi Roberto Da Cas Concita Rafaniello Nadia Mores Giulia Bersani Antonino Reale Nicola Pirozzi Francesca Menniti-Ippolito Giuseppe Traversa Italian Multicenter Study Group for Vaccine Safety in Drug Children 《PloS one》2013,8(7)
Objective
Stevens-Johnson Syndrome (SJS) is one of the most severe muco-cutaneous diseases and its occurrence is often attributed to drug use. The aim of the present study is to quantify the risk of SJS in association with drug and vaccine use in children.Methods
A multicenter surveillance of children hospitalized through the emergency departments for acute conditions of interest is currently ongoing in Italy. Cases with a diagnosis of SJS were retrieved from all admissions. Parents were interviewed on child’s use of drugs and vaccines preceding the onset of symptoms that led to the hospitalization. We compared the use of drugs and vaccines in cases with the corresponding use in a control group of children hospitalized for acute neurological conditions.Results
Twenty-nine children with a diagnosis of SJS and 1,362 with neurological disorders were hospitalized between 1st November 1999 and 31st October 2012. Cases were more frequently exposed to drugs (79% vs 58% in the control group; adjusted OR 2.4; 95% CI 1.0–6.1). Anticonvulsants presented the highest adjusted OR: 26.8 (95% CI 8.4–86.0). Significantly elevated risks were also estimated for antibiotics use (adjusted OR 3.3; 95% CI 1.5–7.2), corticosteroids (adjusted OR 4.2; 95% CI 1.8–9.9) and paracetamol (adjusted OR 3.2; 95% CI 1.5–6.9). No increased risk was estimated for vaccines (adjusted OR: 0.9; 95% CI 0.3–2.8).Discussion
Our study provides additional evidence on the etiologic role of drugs and vaccines in the occurrence of SJS in children. 相似文献6.
Daniela Tagliaferri Maria Teresa De Angelis Nicola Antonino Russo Maria Marotta Michele Ceccarelli Luigi Del Vecchio Mario De Felice Geppino Falco 《PloS one》2016,11(2)
Pluripotency confers Embryonic Stem Cells (ESCs) the ability to differentiate in ectoderm, endoderm, and mesoderm derivatives, producing the majority of cell types. Although the majority of ESCs divide without losing pluripotency, it has become evident that ESCs culture consists of multiple cell populations with different degrees of potency that are spontaneously induced in regular ESC culture conditions. Zscan4, a key pluripotency factor, marks ESC subpopulation that is referred to as high-level of pluripotency metastate. Here, we report that in ESC cultures treated with retinoic acid (RA), Zscan4 ESCs metastate is strongly enhanced. In particular, we found that induction of Zscan4 metastate is mediated via RA receptors (RAR-alpha, RAR-beta, and RAR-gamma), and it is dependent on phosphoinositide-3-kinase (PI3K) signaling. Remarkably, Zscan4 metastate induced by RA lacks canonical pluripotency genes Oct3/4 and Nanog but retained both self-renewal and pluripotency capabilities. Finally we demonstrated that the conditional ablation of Zscan4 subpopulation is dispensable for both endoderm and mesoderm but is required for ectoderm lineage. In conclusion, our research provides new insights about the role of RA signaling during ESCs high pluripotency metastate fluctuation. 相似文献
7.
Giacomo Zaccone John Maina Antonino Germanà Giuseppe Montalbano Gioele Capillo Luisa Aragona Michał J. Kuciel Eugenia Rita Lauriano José M. Icardo 《Acta zoologica》2019,100(2):160-166
Available studies that have examined O2 sensing in fish have indicated that oxygen-sensitive neuroepithelial cells (NECs) are O2 sensors in the gills and initiate cardiorespiratory reflexes in aquatic vertebrates. This is the first study describing the occurrence of NECs in accessory respiratory organs in the air-breathing catfish Clarias gariepinus. Immunocytochemical stainings with specific neuronal markers such as nNOS, VAchT, 5-HT and TH have been shown to be very useful for location and distribution of these cells in the gill fans and suprabranchial chamber that take origin from the transformation of the gill tissue. But the response of these putative O2 chemoreceptors, their role in the respiratory reflexes and their innervation await investigation. 相似文献
8.
Biodegradation of phenols by microalgae 总被引:7,自引:0,他引:7
Gabriele Pinto Antonino Pollio Lucio Previtera Fabio Temussi 《Biotechnology letters》2002,24(24):2047-2051
Two green microalgae, Ankistrodesmus braunii and Scenedesmus quadricauda, degraded phenols (each tested at 400 mg ml–1) selected from olive-oil mill wastewaters, within 5 days, with a removal greater than 70%. Green algae may, therefore, represent an alternative to other biological treatment used for the biodegradation of phenol-containing wastewaters. 相似文献
9.
We recently reported the isolation and sequencing of human cDNA clones corresponding to the alpha 3 chain of type VI collagen (Chu, M.-L., Zhang, R.-Z., Pan, T.-c., Stokes, D., Conway, D., Kuo, H.-J., Glanville, R., Mayer, U., Mann, K., Deutzmann, R., and Timpl, R. (1990) EMBO J. 9, 385-393). The study indicates that the amino-terminal globular domain of the alpha 3(VI) chain consists of nine repetitive subdomains of approximately 200 amino acid residues (N1-N9) and the gene appeared to undergo alternative splicing since some clones lacked regions encoding the N9 and part of the N3 subdomains. In the present study, we report the exon structure for the region encoding the amino-terminal globular domain of the human alpha 3(VI) chain. The nine repetitive subdomains are encoded by 10 exons spanning 26 kilobase pairs of genomic DNA. Eight of the repetitive subdomains (N2-N9) were found to be encoded by separate exons of approximately 600 base pairs each. The only exception is the N1 subdomain which is encoded by two exons of 417 and 146 base pairs. Characterization of the exon/intron structure showed that the cDNA variants were the result of splicing out of exon 9 (encoding the N9 subdomain) and part of exon 3 (encoding the N3 subdomain). Nuclease S1 analysis and the polymerase chain reaction demonstrated that exon 7 (N7 subdomain) was also subject to alternative splicing in normal skin fibroblasts. Examination of these splicing events by nuclease S1 analysis in normal fibroblasts, three different human tumor cell lines, and several human tissues showed that splicing out of exon 9 is much more efficient in normal as compared to tumor cells. 相似文献
10.
Oxidative damage of the gastric mucosa in Helicobacter pylori positive chronic atrophic and nonatrophic gastritis, before and after eradication 总被引:3,自引:0,他引:3
Iacopini F Consolazio A Bosco D Marcheggiano A Bella A Pica R Paoluzi OA Crispino P Rivera M Mottolese M Nardi F Paoluzi P 《Helicobacter》2003,8(5):503-512
Background. Helicobacter pylori is the main cause of gastritis and a primary carcinogen. The aim of this study was to assess oxidative damage in mucosal compartments of gastric mucosa in H. pylori positive and negative atrophic and nonatrophic gastritis. Materials and methods. Five groups of 10 patients each were identified according to H. pylori positive or negative chronic atrophic (Hp‐CAG and CAG, respectively) and nonatrophic gastritis (Hp‐CG and CG, respectively), and H. pylori negative normal mucosa (controls). Oxidative damage was evaluated by nitrotyrosine immunohistochemistry in the whole mucosa and in each compartment at baseline and at 2 and 12 months after eradication. Types of intestinal metaplasia were classified by histochemistry. Results. Total nitrotyrosine levels appeared significantly higher in H. pylori positive than in negative patients, and in Hp‐CAG than in Hp‐CG (p < .001); no differences were found between H. pylori negative gastritis and normal mucosa. Nitrotyrosine were found in foveolae and intestinal metaplasia only in Hp‐CAG. At 12 months after H. pylori eradication, total nitrotyrosine levels showed a trend toward a decrease in Hp‐CG and decreased significantly in Hp‐CAG (p = .002), disappearing from the foveolae (p = .002), but remaining unchanged in intestinal metaplasia. Type I and II of intestinal metaplasia were present with the same prevalence in Hp‐CAG and CAG, and did not change after H. pylori eradication. Conclusions. Oxidative damage of the gastric mucosa increases from Hp‐CG to Hp‐CAG, involving the foveolae and intestinal metaplasia. H. pylori eradication induces a complete healing of foveolae but not of intestinal metaplasia, reducing the overall oxidative damage in the mucosa. 相似文献