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141.
142.
Hugo M. Botelho Sónia S. Leal Isabel Cardoso Kiran Yanamandra Ludmilla A. Morozova-Roche Günter Fritz Cláudio M. Gomes 《The Journal of biological chemistry》2012,287(50):42233-42242
S100A6 is a small EF-hand calcium- and zinc-binding protein involved in the regulation of cell proliferation and cytoskeletal dynamics. It is overexpressed in neurodegenerative disorders and a proposed marker for Amyotrophic Lateral Sclerosis (ALS). Following recent reports of amyloid formation by S100 proteins, we investigated the aggregation properties of S100A6. Computational analysis using aggregation predictors Waltz and Zyggregator revealed increased propensity within S100A6 helices HI and HIV. Subsequent analysis of Thioflavin-T binding kinetics under acidic conditions elicited a very fast process with no lag phase and extensive formation of aggregates and stacked fibrils as observed by electron microscopy. Ca2+ exerted an inhibitory effect on the aggregation kinetics, which could be reverted upon chelation. An FT-IR investigation of the early conformational changes occurring under these conditions showed that Ca2+ promotes anti-parallel β-sheet conformations that repress fibrillation. At pH 7, Ca2+ rendered the fibril formation kinetics slower: time-resolved imaging showed that fibril formation is highly suppressed, with aggregates forming instead. In the absence of metals an extensive network of fibrils is formed. S100A6 oligomers, but not fibrils, were found to be cytotoxic, decreasing cell viability by up to 40%. This effect was not observed when the aggregates were formed in the presence of Ca2+. Interestingly, native S1006 seeds SOD1 aggregation, shortening its nucleation process. This suggests a cross-talk between these two proteins involved in ALS. Overall, these results put forward novel roles for S100 proteins, whose metal-modulated aggregation propensity may be a key aspect in their physiology and function. 相似文献
143.
Gregório Miguel Ferreira de Camargo Diercles Francisco Cardoso Fernanda Maria Monsalves Gil Patrícia Dias da Silva Fonseca Larissa Zetouni Camila Urbano Braz Ana Claudia de Freitas Fábio Ricardo Pablos de Souza Rusbel Raul Aspilcueta-Borquis Fernando Baldi Lucia Galv?o de Albuquerque Luciana Correia de Almeida Regitano Humberto Tonhati 《Molecular biology reports》2012,39(12):10105-10109
Protein JY-1 is a bovine oocyte-specific protein that regulates granulosa cell function and is involved in early embryonic development, influencing the chance of pregnancy. This study investigated molecular markers for the JY-1 gene. Seven SNPs were identified in exon 3 of the gene. The positions of the SNPs in the exon and the respective substitutions are: 163 (T/C), 281 (T/C), 321 (T/C), 532 (T/C), 652 (A/G), 679 (T/C), and 722 (G/C) (GenBank: JN592587 and JF262042.2). SNP 163 is located in a coding region and causes a proline-to-leucine substitution. The other SNPs are located in the 3′UTR region. SNPs 163, 281, 321, and 679 were genotyped in 297 Nellore heifers and the haplotypes were constructed. The haplotypes of JY-1 were not correlated with the traits studied at 5?%. 相似文献
144.
Tatiane Katsue Furuya Patrícia Natália Oliveira da Silva Spencer Luiz Marques Payão Lucas Trevizani Rasmussen Roger Willian de Labio Paulo Henrique Ferreira Bertolucci Ianna Lacerda Sampaio Braga Elizabeth Suchi Chen Gustavo Turecki Naguib Mechawar Jonathan Mill Marília de Arruda Cardoso Smith 《Neurochemistry international》2012
Alzheimer’s Disease (AD) is a neurodegenerative disorder and the most common cause of dementia among the elderly. Efforts have been made to understand the genetic and epigenetic mechanisms involved in the development of this disease. As SORL1 (sortilin-related receptor) and SIRT1 (sirtuin 1) genes have been linked to AD pathogenesis, we aimed to investigate their mRNA expression and promoter DNA methylation in post mortem brain tissues (entorhinal and auditory cortices and hippocampus) from healthy elderly subjects and AD patients. We also evaluated these levels in peripheral blood leukocytes from young, healthy elderly and AD patients, investigating whether there was an effect of age on these profiles. The comparative CT method by Real Time PCR and MALDI-TOF mass spectrometry were used to analyze gene expression and DNA methylation, respectively. SORL1 gene was differently expressed in the peripheral blood leukocytes and might act as a marker of aging in this tissue. Furthermore, we found that SORL1 promoter DNA methylation might act as one of the mechanisms responsible for the differences in expression observed between blood and brain for both healthy elderly and AD patients groups. The impact of these studied genes on AD pathogenesis remains to be better clarified. 相似文献
145.
do Prado MF Coelho AC de Brito JP Ferreira DO Junior AW Menecucci Cda S de Queiroz AB Garcia LB Cardoso CL Tognim MC 《Letters in applied microbiology》2012,54(6):564-567
Aims: The objective of this study was to assess the antimicrobial efficacy of alcohol‐based hand gels according to European Norm 1500 (EN 1500). Methods and Results: We assessed the antimicrobial efficacy of 12 alcohol‐based hand gels produced in Brazil, containing 70% w/w or v/v ethyl alcohol as the active ingredient, according to EN 1500, with a 30‐s application. In addition, 70% w/w ethyl alcohol and three alcohol‐based hand rubs commonly used in Europe and effective according to EN 1500 were also tested. Eight of 12 (67%) alcohol‐based hand gels produced in Brazil failed by EN 1500. In contrast, 70% w/w ethyl alcohol and European alcohol‐based hand rubs were approved by EN 1500. Conclusions: In this study, the majority of Brazilian alcohol‐based hand gels showed limited efficacy on hand hygiene within 30 s. Significance and Impact of the Study: The findings of this study may be used as an important argument to motivate Brazilian manufacturers to improve the antimicrobial efficacy of alcohol‐based hand gels, because it is prudent to suppose that alcohol‐based hand gels can be recommended for use in healthcare settings only if they show antimicrobial activity at least similar to that of alcohol‐based liquid preparations, including the traditional 70% w/w ethyl alcohol. 相似文献
146.
Although many studies have evaluated the possible rules used by males to settle territorial contests, few have simultaneously
considered the possibility of mutual or self-assessment of fighting ability and the effect of prior residence on the chances
of winning. Here, we experimentally investigated the influence of previous residency on the development and outcome of contests
between males of the butterfly Hermeuptychia fallax. By comparing the frequency of resident victories in nonmanipulated disputes versus interactions in which both rivals were
induced to behave as residents, we showed that prior residency may interact with body mass in contest resolution. In nonmanipulated
disputes, resident males showed high winning probabilities, although they were similar to losers in body mass. However, when
both males behaved as residents, the disputes were longer and were settled in favor of the heavier male. This indicates that,
although residency is an important component of male willingness to fight, it is not the only factor influencing conflict
resolution. Despite the correlation between body mass and territorial success, the weight of neither winners nor losers correlated
with fighting duration. We conclude that residence asymmetry may sometimes conceal male traits important to contest resolution
and that it may obscure the identification of the assessment strategy used in contests. 相似文献
147.
Cardoso CA Pinto JA Candiani TM Carvalho IR Linhares RM Goulart EM 《Memórias do Instituto Oswaldo Cruz》2012,107(4):532-538
The use of highly active antiretroviral therapy (HAART) for human immunodeficiency virus (HIV)-infected patients has reduced the number of acquired immune deficiency syndrome-related deaths worldwide. This study assessed the impact of HAART on the survival and death rates of vertically HIV-infected children and adolescents in Belo Horizonte, Brazil. Data were obtained from a historic cohort of vertically HIV-infected children and adolescents aged zero-19 years old who were admitted from March 1989-December 2004 and were followed until June 2006. Patients who used HAART were included if they were treated for at least 12 weeks. Of 359 patients, 320 patients met the inclusion criteria. The overall mortality rate was 9.7% [31/320; 95% confidence interval (CI): 6.0-13%]. The median survival for the non-HAART and HAART groups was 31.5 and 55.9 months, respectively (log rank = 22.11, p < 0.0001). In the multivariate analysis, the statistically significant variables were HAART and the weight-for-age Z score < -2, with HAART constituting a protective factor [relative risk (RR): 0.13; CI 95%: 0.05-0.33] and malnutrition constituting a risk factor (RR: 3.44; CI 95%: 1.60-7.40) for death. The incidence of death was 5.1/100 person-years in the non-HAART group and 0.8/100 person-years in the HAART group (p < 0.0001). 相似文献
148.
Procópio L Alvarez VM Jurelevicius DA Hansen L Sørensen SJ Cardoso JS Pádula M Leitão AC Seldin L van Elsas JD 《Antonie van Leeuwenhoek》2012,101(2):289-302
The draft genome of Dietzia cinnamea strain P4 was determined using pyrosequencing. In total, 428 supercontigs were obtained and analyzed. We here describe and
interpret the main features of the draft genome. The genome contained a total of 3,555,295 bp, arranged in a single replicon
with an average G+C percentage of 70.9%. It revealed the presence of complete pathways for basically all central metabolic
routes. Also present were complete sets of genes for the glyoxalate and reductive carboxylate cycles. Autotrophic growth was
suggested to occur by the presence of genes for aerobic CO oxidation, formate/formaldehyde oxidation, the reverse tricarboxylic
acid cycle and the 3-hydropropionate cycle for CO2 fixation. Secondary metabolism was evidenced by the presence of genes for the biosynthesis of terpene compounds, frenolicin,
nanaomycin and avilamycin A antibiotics. Furthermore, a probable role in azinomycin B synthesis, an important product with
antitumor activity, was indicated. The complete alk operon for the degradation of n-alkanes was found to be present, as were clusters of genes for biphenyl ring dihydroxylation. This study brings new insights
in the genetics and physiology of D. cinnamea P4, which is useful in biotechnology and bioremediation. 相似文献
149.
André Luiz Alves de Lima Everardo Valadares de Sá Barretto Sampaio Cibele Cardoso de Castro Maria Jesus Nogueira Rodal Ant?nio Celso Dantas Antonino André Laurênio de Melo 《Trees - Structure and Function》2012,26(5):1605-1616
The phenology of tree species in environments that are subject to strong climatic seasonality is mainly determined by water availability, which may vary as a function of wood density. The relationship among phenology, water potential, wood density and the capacity of water storage in the stem were determined for woody species of caatinga vegetation (dry forest) in the semiarid region of NE Brazil. Leaf flush and fall, flowering and fruiting events were recorded over a 31-month period, and the water potential was measured over a two-year period. These data were related to precipitation, water availability in the soil and photoperiod. Seven deciduous species exhibited low wood density (DLWD,?<0.5?g?cm?3), high capacity of water storage in the stem (until 250?% of the dry weight) and high water potential during the year, as opposed to 15 deciduous species that showed high wood density (DHWD,?≥0.5?g?cm?3). Leaf flush, flowering and the fruiting of DHWD species were related to precipitation, whereas these phenological events occurred at the end of the dry season and/or the beginning of the rainy season for DLWD species and were related to the photoperiod. The two evergreen species showed variations of water potential that were intermediate between those of DHWD and DLWD deciduous species, leaf flush during the dry season and flowering at the end of dry season. These results suggest the existence of three functional groups: evergreen species, DHWD deciduous species and DLWD deciduous species. 相似文献
150.
Ferreira SM Domingos GP Ferreira Ddos S Rocha TG Serakides R de Faria Rezende CM Cardoso VN Fernandes SO Oliveira MC 《Bioorganic & medicinal chemistry letters》2012,22(14):4605-4608
Osteomyelitis is an infectious disease located in the bone or bone marrow. Long-circulating and pH-sensitive liposomes containing a technetium-99m-labeled antibiotic, ceftizoxime, (SpHL-(99m)Tc-CF) were developed to identify osteomyelitis foci. Biodistribution studies and scintigraphic images of bone infection or non infection-bearing rats that had been treated with these liposomes were performed. A high accumulation in infectious foci and high values in the target-non target ratio could be observed. These results indicate the potential of SpHL-(99m)Tc-CF as a potential agent for the diagnosis of bone infections. 相似文献