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2.
Chromosome abnormalities in tuberous sclerosis 总被引:1,自引:1,他引:0
Susi Scappaticci D. Cerimele M. Tondi Rossella Vivarelli A. Fois M. Fraccaro 《Human genetics》1988,79(2):151-156
Summary In fibroblasts cultured from biopsies of the skin lesions of six patients with tuberous sclerosis (TS) there was a variable but consistent degree of karyotypic variation. Premature centromere disjunction (PCD) of all or part of the chromosomes, micronuclei, an increased incidence of breaks, dicentric chromosomes and the presence of polyploid metaphases were found in all cultures. The PCD was of the type encountered in Roberts syndrome and its frequency varied from 8% to 30%. In metaphases with PCD of one and of two chromosomes, the chromosome involved were identified, and chromosome 3 was involved 21 times among 59 chromosomes with PCD. Chromosome 3 tends to be preferentially involved in dicentric formation. In lymphocyte cultures from the same patients there were no metaphases with PCD, but there was a slight increase of breaks and the presence of dicentric chromosomes, also involving chromosome 3. Polyploid metaphases were increased in some of the cases. Karyotypic variation can be considered a cellular phenotypic characteristic of TS in fibroblasts cultured from the skin lesions, and its type indicates disturbances in the mechanics of centromere division and of chromosome distribution at cell division. 相似文献
3.
Rossella Serra Gloria Isani Otello Cattani Emilio Carpené 《Biological trace element research》1996,51(1):107-116
Gilthead were fed three diets. Diet A was the control diet, whereas diets B and C were supplemented with 300 and 900 mg Zn/kg,
respectively. Fish fed with diet C, at the end of the experiment, showed the lowest weight. Zinc concentrations presented
the higher values in gills, liver, and kidney. Muscle and brain had the lower mean values and showed a tight control of zinc
levels. These results reinforce the hypothesis that zinc in the CNS should be strictly controlled in order to maintain the
functional role of the metal. Significant differences in tissue zinc concentrations were obtained between fish fed different
amounts of zinc, the metal concentrations being higher in tissues of fish fed diet C. The tissue decrease of zinc, found at
the end of the experiment, may depend on a lower feed consumption or on different zinc requirements during the cold season.
These changes, even if not univocal among the three diets, may be associated with the life cycle of fish. Furthermore, copper
concentrations were little affected by the different concentrations of zinc in the three diets; liver and kidney presented
the highest concentrations; liver showed a significant decrease in copper content at the end of the experiment. We conclude
that: zinc concentrations of the diet may affect the gilthead weights and the tissual metal content; and zinc concentrations
in the diets, depending on the growth rate, may be varied depending on the season. 相似文献
4.
Abstract This paper deals with the anatomical and histological study of a silicified specimen of a palm consisting of a part of the trunk surrounded by roots. The sample comes from the Lower Miocene of North West Sardinia. The comparison with fossil species and exsting species leads to the conclusion that the specimen belongs to a new fossil species closely related to Chamaerops humilis L., widespread throughout the Mediterranean area. Paleo-environmental considerations confirm the presence in Sardinia, in the epoch in question, of formations of Mediterranean forest corresponding in part to forest existing in North Africa today. 相似文献
5.
Stefania Galdiero Annarita Falanga Rossella Tarallo Luigi Russo Emilia Galdiero Marco Cantisani Giancarlo Morelli Massimiliano Galdiero 《Journal of peptide science》2013,19(3):148-158
Herpes simplex virus (HSV) is a significant human pathogen causing mucocutaneous lesions primarily in the oral or genital mucosa. Although acyclovir (ACV) and related nucleoside analogs provide successful treatment, HSV remains highly prevalent worldwide and is a major cofactor for the spread of human immunodeficiency virus. Encephalitis, meningitis, and blinding keratitis are among the most severe diseases caused by HSV. ACV resistance poses an important problem for immunocompromised patients and highlights the need for new safe and effective agents; therefore, the development of novel strategies to eradicate HSV is a global public health priority. Despite the continued global epidemic of HSV and extensive research, there have been few major breakthroughs in the treatment or prevention of the virus since the introduction of ACV in the 1980s. A therapeutic strategy at the moment not fully addressed is the use of small peptide molecules. These can be either modeled on viral proteins or derived from antimicrobial peptides. Any peptide that interrupts protein–protein or viral protein–host cell membrane interactions is potentially a novel antiviral drug and may be a useful tool for elucidating the mechanisms of viral entry. This review summarizes current knowledge and strategies in the development of synthetic and natural peptides to inhibit HSV infectivity. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
6.
Rossella Falcone Sara Bevacqua Erika Cerasti Emiliano Brunamonti Milena Cervelloni Aldo Genovesio 《PloS one》2013,8(12)
To solve novel problems, it is advantageous to abstract relevant information from past experience to transfer on related problems. To study whether macaque monkeys were able to transfer an abstract rule across cognitive domains, we trained two monkeys on a nonmatch-to-goal (NMTG) task. In the object version of the task (O-NMTG), the monkeys were required to choose between two object-like stimuli, which differed either only in shape or in shape and color. For each choice, they were required to switch from their previously chosen object-goal to a different one. After they reached a performance level of over 90% correct on the O-NMTG task, the monkeys were tested for rule transfer on a spatial version of the task (S-NMTG). To receive a reward, the monkeys had to switch from their previously chosen location to a different one. In both the O-NMTG and S-NMTG tasks, there were four potential choices, presented in pairs from trial-to-trial. We found that both monkeys transferred successfully the NMTG rule within the first testing session, showing effective transfer of the learned rule between two cognitive domains. 相似文献
7.
Rossella Valentino Vittoria D’Esposito Federica Passaretti Antonietta Liotti Serena Cabaro Michele Longo Giuseppe Perruolo Francesco Oriente Francesco Beguinot Pietro Formisano 《PloS one》2013,8(12)
Current evidence indicates that chemical pollutants may interfere with the homeostatic control of nutrient metabolism, thereby contributing to the increased prevalence of metabolic disorders. Bisphenol-A (BPA) is a lipophilic compound contained in plastic which is considered a candidate for impairing energy and glucose metabolism. We have investigated the impact of low doses of BPA on adipocyte metabolic functions. Human adipocytes derived from subcutaneous adipose tissue and differentiated 3T3-L1 cells were incubated with BPA, in order to evaluate the effect on glucose utilization, insulin sensitivity and cytokine secretion. Treatment with 1nM BPA significantly inhibited insulin-stimulated glucose utilization, without grossly interfering with adipocyte differentiation. Accordingly, mRNA levels of the adipogenic markers PPARγ and GLUT4 were unchanged upon BPA exposure. BPA treatment also impaired insulin-activated receptor phosphorylation and signaling. Moreover, adipocyte incubation with BPA was accompanied by increased release of IL-6 and IFN-γ, as assessed by multiplex ELISA assays, and by activation of JNK, STAT3 and NFkB pathways. Treatment of the cells with the JNK inhibitor SP600125 almost fully reverted BPA effect on insulin signaling and glucose utilization. In conclusion, low doses of BPA interfere with inflammatory/insulin signaling pathways, leading to impairment of adipose cell function. 相似文献
8.
Ada Rispoli Elena Cipollini Sandra Catania Rossella Di Giaimo Giuseppe Pulice Stineke van Houte Francesca Sparla Fabrizio Dal Piaz Davide Roncarati Paolo Trost Marialuisa Melli 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(12):2591-2599
Cystatin B (CSTB) is an anti-protease frequently mutated in progressive myoclonus epilepsy (EPM1), a devastating degenerative disease. This work shows that rat CSTB is an unstable protein that undergoes structural changes following the interaction with a chaperone, either prokaryotic or eukaryotic. Both the prokaryotic DnaK and eukaryotic HSP70 promote CSTB polymerization. Denaturated CSTB is polymerized by the chaperone alone. Native CSTB monomers are more stable than denatured monomers and require Cu2 + for chaperone-dependent polymerization. Cu2 + interacts with at least two conserved histidines, at positions 72 and 95 modifying the structure of native monomeric CSTB. Subsequently, CSTB becomes unstable and readily responds to the addition of DnaK or HSP70, generating polymers. This reaction depends strictly on the presence of this divalent metal ion and on the presence of one cysteine in the protein chain. The cysteine deletion mutant does not polymerize. We propose that Cu2 + modifies the redox environment of the protein, allowing the oxidation of the cysteine residue of CSTB that triggers polymerization. These polymers are sensitive to reducing agents while polymers obtained from denatured CSTB monomers are DTT resistant. We propose that the Cu2 +/HSP70 dependent polymers are physiological and functional in eukaryotic cells. Furthermore, while monomeric CSTB has anti-protease function, it seems likely that polymeric CSTB fulfils different function(s). 相似文献
9.
Tiziana Bozzini Giorgia Botta Michela Delfino Silvano Onofri Raffaele Saladino Donatella Amatore Rossella Sgarbanti Lucia Nencioni Anna Teresa Palamara 《Bioorganic & medicinal chemistry》2013,21(24):7699-7708
Catechol derivatives with lipophilic properties have been selectively synthesized by tyrosinase in high yield avoiding long and tedious protection/deprotection steps usually required in traditional procedures. The synthesis was effective also with immobilized tyrosinase able to perform for more runs. The novel catechols were evaluated against influenza A virus, that continue to represent a severe threat worldwide. A significant antiviral activity was observed in derivatives characterized by antioxidant activity and long carbon alkyl side-chains, suggesting the possibility of a new inhibition mechanism based on both redox and lipophilic properties. 相似文献
10.
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)