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191.
A range of lignocellulosic feedstocks (including agricultural, softwood and hardwood substrates) were pretreated with either
sulfur dioxide-catalyzed steam or an ethanol organosolv procedure to try to establish a reliable assessment of the factors
governing the minimum protein loading that could be used to achieve efficient hydrolysis. A statistical design approach was
first used to define what might constitute the minimum protein loading (cellulases and β-glucosidase) that could be used to
achieve efficient saccharification (defined as at least 70% glucan conversion) of the pretreated substrates after 72 hours
of hydrolysis. The likely substrate factors that limit cellulose availability/accessibility were assessed, and then compared
with the optimized minimum amounts of protein used to obtain effective hydrolysis. The optimized minimum protein loadings
to achieve efficient hydrolysis of seven pretreated substrates ranged between 18 and 63 mg protein per gram of glucan. Within
the similarly pretreated group of lignocellulosic feedstocks, the agricultural residues (corn stover and corn fiber) required
significantly lower protein loadings to achieve efficient hydrolysis than did the pretreated woody biomass (poplar, douglas
fir and lodgepole pine). Regardless of the substantial differences in the source, structure and chemical composition of the
feedstocks, and the difference in the pretreatment technology used, the protein loading required to achieve efficient hydrolysis
of lignocellulosic substrates was strongly dependent on the accessibility of the cellulosic component of each of the substrates.
We found that cellulose-rich substrates with highly accessible cellulose, as assessed by the Simons' stain method, required
a lower protein loading per gram of glucan to obtain efficient hydrolysis compared with substrates containing less accessible
cellulose. These results suggest that the rate-limiting step during hydrolysis is not the catalytic cleavage of the cellulose
chains per se, but rather the limited accessibility of the enzymes to the cellulose chains due to the physical structure of the cellulosic
substrate. 相似文献
192.
Shirlee Jaffe Georgios Doulaveris Theofano Orfanelli Mariana Arantes Débora Damasceno Iracema Calderon Marilza V. C. Rudge Steven S. Witkin 《Cell stress & chaperones》2013,18(4):527-530
Obese Black women are at increased risk for development of gestational diabetes mellitus and have worse perinatal outcomes than do obese women of other ethnicities. Since hsp72 has been associated with the regulation of obesity-induced insulin resistance, we evaluated associations between glucose ingestion, hsp72 release and insulin production in Black pregnant women. Specifically, the effect of a 50-g glucose challenge test (GCT) on heat shock protein and insulin levels in the circulation 1 h later was evaluated. Hsp27 and hsp60 levels remained unchanged. In contrast, serum levels of hsp72 markedly increased after glucose ingestion (p = 0.0054). Further analysis revealed that this increase was limited to women who were not obese (body mass index <30). Insulin levels pre-GCT were positively correlated with body mass index (p = 0.0189). Median insulin concentrations also increased post GCT in non-obese women but remained almost unchanged in obese women. Post-GCT serum hsp72 concentrations were inversely correlated with post GCT insulin concentrations (p = 0.0111). These observations suggest that glucose intake during gestation in Black women rapidly leads to an elevation in circulating hsp72 only in non-obese Black women. The release of hsp72 may regulate the extent of insulin production in response to a glucose challenge and, thereby, protect the mother and/or fetus from development of hyperglycemia, hyperinsulinemia, and/or immune system alterations. 相似文献
193.
Eliane Matos dos Santos Gloria Regina da Silva e Sá Marilda Mendon?a Siqueira Reinaldo de Menezes Martins Luiz Antonio Bastos Camacho Vanessa dos Reis von Doellinger Maria de Lourdes de Sousa Maia 《Memórias do Instituto Oswaldo Cruz》2014,109(3):335-339
A non-controlled longitudinal study was conducted to evaluate the combined vaccine
against measles, mumps and rubella (MMR) immunogenicity in 150 children vaccinated in
the routine of three health units in the city of Rio de Janeiro, Brazil, 2008-2009,
without other vaccines administered during the period from 30 days before to 30 days
after vaccination. A previous study conducted in Brazil in 2007, in 1,769 children
ranging from 12-15 months of age vaccinated against yellow fever and MMR
simultaneously or at intervals of 30 days or more between doses, had shown low
seroconversion for mumps regardless of the interval between administration of the two
vaccines. The current study showed 89.5% (95% confidence interval: 83.3; 94.0)
seroconversion rate for mumps. All children seroconverted for measles and rubella.
After revaccination, high antibody titres and seroconversion rates were achieved
against mumps. The results of this study and others suggest that two MMR doses confer
optimal immunoresponses for all three antigens and the possible need for additional
doses should be studied taking into account not only serological, but also
epidemiological data, as there is no serological correlate of protection for
mumps. 相似文献
194.
I G Arantes A A do Nascimento E I Gon?alves O Ferrari 《Arquivos do Instituto Biológico》1977,44(1-2):115-116
Cooperia curticei Giles, 1892 (Nematoda: Trichostrongylidae) is reported, for the first time, parasitizing the small intestine of goats (Capra hircus) in the State of S?o Paulo, Brazil. The animals came from the Region of the Alta Araraquarense. The spicules of the worms were well chitinized and measured, on the average, 153,68 micrometer with a standard error of 0,91 micrometer. 相似文献
195.
196.
Heterochromatin Bands and rDNA Sites Evolution in Polyploidization Events in Cynodon Rich. (Poaceae)
Chiavegatto Raquel Bezerra Chaves Ana Luisa Arantes Rocha Laiane Corsini Benites Flávio Rodrigo Gandolfi Peruzzi Lorenzo Techio Vânia Helena 《Plant Molecular Biology Reporter》2019,37(5-6):477-487
Plant Molecular Biology Reporter - Cynodon is a genus with a wide distribution in tropical and subtropical areas. Ploidy levels in Cynodon range from diploid to hexaploid; hence, polyploidy is the... 相似文献
197.
Rafael Magno Costa Melo Fábio Pereira Arantes Yoshimi Sato José Enemir dos Santos Elizete Rizzo Nilo Bazzoli 《Journal of morphology》2011,272(5):525-535
We studied the relationship between the morphology of the reproductive system and the reproductive strategies of six neotropical catfishes using macroscopic and microscopic analyses. The reproductive system of the examined Siluriformes showed diversified characteristics, but permitted their being grouped according to three reproductive strategies: pelagic spawning, demersal spawning, and internally fertilizing. The pelagic spawners Pseudoplatystoma corruscans and Conorhynchos conirostris have testes that are characterized by filiform lobes, absence of testicular secretion, full‐grown oocytes of small diameter, thin zona radiata, and cuboidal follicular cells. Pimelodus maculatus is morphologically distinct from the other two pelagic spawners catfishes due to the presence of testicular secretion. The demersal spawners Lophiosilurus alexandri and Rhinelepis aspera possess homogeneous testicular secretion, large mature oocytes, and columnar follicular cells. The most specialized reproductive system was observed in the internally fertilizing Trachelyopterus galeatus, which possesses a seminal vesicle accessory to the testes, spermatozoa with elongated nuclei that form spermatozeugmata, and a secretory ovarian lamellar epithelium that is associated with sperm storage. The reproductive system observed in Neotropical catfishes showed a relationship associated with the type of fertilization and the reproductive strategies of the six species studied. © 2011 Wiley‐Liss, Inc. 相似文献
198.
Dream thought is both impoverished and non-logical. While some inferential reasoning is present in dreaming, many illogicalities that would demand cognitive attention during waking go unnoticed during sleep. The physiological basis of this illogicality may include frontal lobe inactivation and amionergic demodulation. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
199.
Paola Cristina Resende Fernando Couto Motta/+ Priscila Silva Born Milene Miranda Marilda M Siqueira 《Memórias do Instituto Oswaldo Cruz》2015,110(1):148-150
The influenza A(H3N2) virus has circulated worldwide for almost five decades and is
the dominant subtype in most seasonal influenza epidemics, as occurred in the 2014
season in South America. In this study we evaluate five whole genome sequences of
influenza A(H3N2) viruses detected in patients with mild illness collected from
January-March 2014. To sequence the genomes, a new generation sequencing (NGS)
protocol was performed using the Ion Torrent PGM platform. In addition to analysing
the common genes, haemagglutinin, neuraminidase and matrix, our work also comprised
internal genes. This was the first report of a whole genome analysis with Brazilian
influenza A(H3N2) samples. Considerable amino acid variability was encountered in all
gene segments, demonstrating the importance of studying the internal genes. NGS of
whole genomes in this study will facilitate deeper virus characterisation,
contributing to the improvement of influenza strain surveillance in Brazil. 相似文献
200.
I G Arantes A A do Nascimento E I Gon?alves O Ferrari 《Arquivos do Instituto Biológico》1977,44(1-2):103-106
The authors verified for the first time in the State of S?o Paulo, Brazil, the presence of Cooperia curticei Giles, 1892 (Nematoda: Trichostrongylidae), parasitizing the small intestine of cattle at the Region of Alta Araraquarense. 相似文献