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991.
Several outbreaks caused by pathogenic bacteria are related to the consumption of raw produce contaminated by animal manure. The majority of these outbreaks have been linked to Salmonella spp. We examined the ability of Salmonella enterica serovar Weltevreden to persist and survive in manure and soil as well as disseminate to, and persist on, spinach roots and leaves. Significantly higher numbers of S. Weltevreden inoculated into manure and applied to soil before planting spinach were found in soil than in pot cultures, where the pathogen had been inoculated directly into soil 14 days postplanting. Moreover, the pathogen seemed to disperse from manure to spinach roots, as we observed a continuous increase in the number of contaminated replicate pot cultures throughout the evaluation period. We also found that, in some cases, S. Weltevreden present in the phyllosphere had the ability to persist for the entire evaluation period (21 days), with only slight reductions in cell numbers. The results from the present study show that S. Weltevreden is capable of persisting in soil, roots and shoots for prolonged periods, indicating the importance of strict monitoring of untreated animal manure before considering its application to agricultural land. 相似文献
992.
993.
Pita J Rado-Peralta S Gavela-Pérez T Aragón I Barrios V Rovira A Argente J Soriano-Guillén L 《Peptides》2011,32(5):983-988
Kisspeptin, the product of the hypothalamic KISS1 gene, is a main regulator of the hypothalamic-pituitary-gonadal axis and could be a link between metabolism and reproduction through its interaction with leptin. Kisspeptin could be involved in gonadotropin regulation and responsive to leptin levels from the first stages of life, exhibiting, as does leptin, sexual dimorphism. To test our hypothesis, we have analyzed plasma kisspeptin levels and their possible relationship with gonadotropins and leptin in a cohort composed of newborns (n = 86) and adults (n = 55). Plasma kisspeptin, gonadotropin and leptin levels were measured by RIA and multiplexed bead immunoassays, respectively. We have built a multivariate linear regression model (analyzing kisspeptin and LH separately as dependent variables) by stepwise analysis, incorporating the variables that had shown significant correlation in the univariate analysis. Cord blood samples exhibited high kisspeptin levels 127.01(113-141.02 pmol/l), but these were not sexually dimorphic. The adult population exhibited sexual dimorphism (3.72(2.95-4.49) vs. 1.77(1.23-2.31) pmol/l women vs. men, p < 0.05). Leptin levels showed sexual dimorphism in cord blood samples and also in the adult population. Furthermore, there was a significant interaction between LH and kisspeptin levels and kisspeptin was negatively correlated with age. The high kisspeptin levels observed in cord blood, with no sexual dimorphism, suggest a placental source. The sexual dimorphism exhibited in adulthood supports the notion that there are different sources and/or differential kisspeptin regulation between men and women. 相似文献
994.
Firmino Viviane Caetano Brasil Leandro Schlemmer Martins Renato Tavares Ligeiro Raphael Tonin Alan Júnior José Francisco Gonçalves Juen Leandro 《Limnology》2021,22(3):289-297
Limnology - The conversion of riparian vegetation into monocultures alters the input of allochthonous energy and the heterotrophy of streams. Here, we aimed to assess the implication of leaf litter... 相似文献
995.
Davide Gobbin Leandro Hohl Lisa Conza Mauro Jermini Cesare Gessler Marco Conedera 《Génome》2007,50(12):1089-1103
Southern Switzerland has a long tradition of chestnut cultivation as a staple food. Local inhabitants constantly selected varieties according to the ripening period, the type of use, and the adaptability to the territory. As a result, the panorama of chestnut varieties is very complex, as reflected by more than 120 different variety names in an area of 26,000 ha. Since 1994, 47 varieties have been conserved in the chestnut germplasm of southern Switzerland (CSS), including Marroni, Euro-Japanese, and French varieties. A selection of 164 individuals from the CSS was analysed by 8 SSR markers (4 of which were developed in this study). Microsatellite analysis indicated that the CSS was accurately established, as 86% of the individuals grafted were correctly labeled. The identification of 98 genotypes, 10 clonal chestnut groups, 4 synonym groups, and 12 homonym groups reflected the complex ethnogeographical structure of the chestnut distribution. The 17 Marroni individuals considered clustered in 2 differentiated genetic groups instead of only 1 as expected. The fundamental problem of the frequent cases of homonymy and synonymy is discussed, as is the need for criteria for discriminating between polyclonal varieties and distinct homonymous varieties. 相似文献
996.
997.
Federico Serana Luisa Imberti Maria Pia Amato Giancarlo Comi Claudio Gasperini Angelo Ghezzi Vittorio Martinelli Leandro Provinciali Maria Rosa Rottoli Stefano Sotgiu Sergio Stecchi Michele Vecchio Mauro Zaffaroni Cinzia Cordioli Ruggero Capra 《PloS one》2014,9(4)
Even though anti-interferon beta (IFNβ) antibodies are the main determinants of IFNβ bioactivity loss and Myxovirus-resistance protein A (MxA) is the most established marker of IFNβ biological activity in IFNβ-treated multiple sclerosis patients, their usefulness in the routine clinical practice is still debated. Therefore, 118 multiple sclerosis patients naïve for treatment were enrolled for a 3-year longitudinal observational study mimicking the conditions of a real-world setting. In order to evaluate the kinetics of bioactivity loss in blood samples obtained every 6 months after therapy initiation, MxA and interferon receptor isoform/subunit mRNA were quantified by real-time PCR, anti-IFNβ binding antibodies were detected by radioimmunoprecipitation, and neutralizing antibodies by cytopathic effect inhibition assay. Clinical measures of disease activity and disability progression were also obtained at all time points. We found that, at the individual-patient level, the response to IFNβ therapy was extremely heterogeneous, including patients with stable or transitory, early or late loss of IFNβ bioactivity, and patients with samples lacking MxA mRNA induction in spite of absence of antibodies. No interferon receptor isoform alterations that could explain these findings were found. At the group level, none of these biological features correlated with the measures of clinical disease activity or progression. However, when MxA mRNA was evaluated not at the single time point as a dichotomic marker (induced vs. non-induced), but as the mean of its values measured over the 6-to-24 month period, the increasing average MxA predicted a decreasing risk of short-term disability progression, independently from the presence of relapses. Therefore, a more bioactive treatment, even if unable to suppress relapses, reduces their severity by an amount that is proportional to MxA levels. Together with its feasibility in the routine laboratory setting, these data warrant the quantification of MxA mRNA as a primary tool for a routine monitoring of IFNβ therapy. 相似文献
998.
Leandro M. Vieira Mary E. Spencer Jones Judith E. Winston Alvaro E. Migotto Antonio C. Marques 《PloS one》2014,9(4)
The bryozoan genus Scrupocellaria comprises about 80 species in the family Candidae. We propose a hypothesis for the phylogenetic relationships among species assigned to Scrupocellaria to serve as framework for a phylogenetic classification using 35 morphological characters. Our results suggest that the genus Scrupocellaria is polyphyletic. Scrupocellaria s. str. is redefined according to four morphological features: vibracular chamber with a curved setal groove, ooecium with a single ectooecial fenestra, two axillary vibracula, and a membranous operculum with a distinct distal rim. Thus, the genus includes only 11 species: Scrupocellaria aegeensis, Scrupocellaria delilii, Scrupocellaria harmeri, Scrupocellaria incurvata, Scrupocellaria inermis, Scrupocellaria intermedia, Scrupocellaria jullieni, Scrupocellaria minuta, Scrupocellaria puelcha, Scrupocellaria scrupea, and Scrupocellaria scruposa. The monophyly of Cradoscrupocellaria is supported and five new genera are erected: Aquiloniella n. gen., Aspiscellaria n. gen., Paralicornia n. gen., Pomocellaria n. gen. and Scrupocaberea n. gen. Two other new genera, Bathycellaria n. gen. and Sinocellaria n. gen., are erected to accommodate two poorly known species, Scrupocellaria profundis Osburn and Scrupocellaria uniseriata Liu, respectively. Scrupocellaria congesta is tentatively assigned to Tricellaria. Fifteen species are reassigned to Licornia: Licornia cookie n. comb., Licornia micheli n. comb., Licornia milneri n. comb., Licornia curvata n. comb., Licornia diegensis n. comb., Licornia drachi n. comb., Licornia mexicana n. comb., Licornia pugnax n. comb., Licornia raigadensis n. comb., Licornia regularis n. comb., Licornia resseri n. comb., Licornia securifera n. comb., Licornia spinigera n. comb., Licornia tridentata n. comb., and Licornia wasinensis n. comb. Notoplites americanus n. name is proposed as a replacement name for Scrupocellaria clausa Canu & Bassler. Three fossil species are reassigned to Canda: Canda rathbuni n. comb., Canda triangulata n. comb. and Canda williardi n. comb. A species is reassigned to Notoplites, Notoplites elegantissima n. comb. The generic assignment of eleven species of Scrupocellaria, including Scrupocellaria macandrei, remains uncertain. 相似文献
999.
Anna Carolina Ratto Tempestini Horliana Leandro Chambrone Adriana Moura Foz Hilana Paula Carillo Artese Mariana de Sousa Rabelo Cláudio Mendes Pannuti Giuseppe Alexandre Romito 《PloS one》2014,9(5)
Background
To date, there is no compilation of evidence-based information associating bacteremia and periodontal procedures. This systematic review aims to assess magnitude, duration, prevalence and nature of bacteremia caused by periodontal procedures.Study Design
Systematic ReviewTypes of Studies Reviewed
MEDLINE, EMBASE and LILACS databases were searched in duplicate through August, 2013 without language restriction. Observational studies were included if blood samples were collected before, during or after periodontal procedures of patients with periodontitis. The methodological quality was assessed in duplicate using the modified Newcastle-Ottawa scale (NOS).Results
Search strategy identified 509 potentially eligible articles and nine were included. Only four studies demonstrated high methodological quality, whereas five were of medium or low methodological quality. The study characteristics were considered too heterogeneous to conduct a meta-analysis. Among 219 analyzed patients, 106 (49.4%) had positive bacteremia. More frequent bacteria were S. viridans, A. actinomycetemcomitans P. gingivalis, M. micros and species Streptococcus and Actinomyces, although identification methods of microbiologic assays were different among studies.Clinical Implications
Although half of the patients presented positive bacteremia after periodontal procedures, accurate results regarding the magnitude, duration and nature of bacteremia could not be confidentially assessed. 相似文献1000.
Geraldine Cambridge Rita A. Moura Tania Santos Akif A. Khawaja Joaquim Polido-Pereira Helena Canh?o Maria J. Leandro Jo?o E. Fonseca 《PloS one》2014,9(9)