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991.
992.
Sandra Regina B. R. Sella Carla Masetti Luis Felipe M. Figueiredo Luciana P. S. Vandenberghe João Carlos Minozzo Carlos Ricardo Soccol 《Biotechnology and Bioprocess Engineering》2013,18(1):75-87
A novel cost-effective Bacillus atrophaeus Sterilization Bioindicator System (BIS) with a high quality and performance was developed from a soybean byproduct and compared with the commercial BIS. It was composed of recovery medium and dry-fermented spores with sand as the support. The BIS was developed and optimized using a sequential experimental design strategy. The recovery medium contained soluble starch (1.0 g/L), soybean molasses (30.0 g/L), tryptone (40.0 g/L), and bromothymol blue (0.02 g/L) at pH 8.5. The solid-state fermentation conditions of the bioreactor and environmental humidity had no significant effects on the spore yield and dry-heat resistance. The only substrate mineral that showed a positive effect was Mn2+, allowing Mg2+, K+, and Ca2+ to be eliminated from the formulation. Validation of optimized medium indicated D 160°C = 6.8±1.0 min (3.6 min more than the minimum) and spore yield = 2.3 ± 0.5 × 109 CFU/g dry sand (10,000 × initial values). BIS performance resulted in D 160°C = 6.6 ± 0.1 min. Sporulation and germination kinetics allowed the sporulation process to be reduced to three days, and the growth of heat-damaged spores was sufficient to achieve visual identification of a non-sterile BIS within 21 h. Process economics was a minimum of 23.9%, and process cycle time was reduced from 29 to 15 days. The new BIS parameters demonstrated compliance to all regulatory requirements. No studies have yet described a BIS production from soybean molasses. 相似文献
993.
Lucas Gabriel Viana Barbosa Ellen Nayara Silva de Jesus Lucas Botelho Jerônimo Jamile Silva da Costa Renata Cunha Silva Prof. Dr. William N. Setzer Prof. Dra. Joyce Kelly R. da Silva Prof. Dr. Jofre Jacob da Silva Freitas Prof. Dr. Pablo Luis B. Figueiredo 《化学与生物多样性》2023,20(10):e202301120
This work aims to evaluate the chemical composition, in vitro antioxidant capacity, and in vivo antitumoral activity of S. guianensis essential oil against Ehrlich's ascitic carcinoma and the effects on oxidative stress. The animals (Mus musculus) received a daily dose of S. guianensis oil orally (100 mg/kg) for 9 days. The main constituents of essential oil were curzerenone (16.4±1.5 %), drimenol (13.7±0.2 %), and spathulenol (12.4±0.8 %). S. guianensis oil showed antioxidant activity, inhibiting 11.1 % of DPPH radicals (95.7 mgTE/g); and 15.5 % of the β-carotene peroxidation. The group treated with S. guianensis showed a significant reduction in tumor cells (59.76±12.33) compared to the tumor group (96.88±19.15). Essential oil of S. guianensis decreased MDA levels and increased SOD levels in liver tissue. The essential oil of S. guianensis reduced oxidative stress, and showed antitumor and antioxidant activity, being characterized as a new chemical profile in the investigation of pathologies such as cancer. 相似文献
994.
G.V. Carbonell B.A.L. Fonseca L.T.M. Figueiredo A.L.C. Darini R.M. Yanaguita 《FEMS immunology and medical microbiology》1996,16(3-4):299-307
Abstract Cytotoxins have been implicated in the pathogenesis of bacterial infections. In this study, the influence of different culture conditions was evaluated on cytotoxin production by Serratia marcescens . Parameters such as culture media, incubation temperature, starting pH of culture medium, aeration, anaerobiosis, carbon sources, iron concentration in the culture media, and release of cell-bound toxin by polymyxin B were investigated. The data suggest that this cytotoxin is predominantly extracellular and is not induced by iron limitation. Aerobic culture with shaking resulted in higher cytotoxicity than static aerobic or anaerobic culture. Bacteria grown in glucose, sucrose or galactose were more cytotoxic than those grown in inositol or maltose. The culture conditions that were identified as optimal for cytotoxin production by Serratia marcescens were incubation temperature ranging from 30 to 37°C, in medium adjusted to pH 8.5, with shaking. This work will contribute to further studies on the identification of this cytotoxic activity. 相似文献
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Rodrigo Augusto Lima Santos Sara M. Santos Margarida Santos-Reis Almir Pican?o de Figueiredo Alex Bager Ludmilla M. S. Aguiar Fernando Ascens?o 《PloS one》2016,11(11)
Carcass persistence time and detectability are two main sources of uncertainty on roadkill surveys. In this study, we evaluate the influence of these uncertainties on roadkill surveys and estimates. To estimate carcass persistence time, three observers (including the driver) surveyed 114km by car on a monthly basis for two years, searching for wildlife-vehicle collisions (WVC). Each survey consisted of five consecutive days. To estimate carcass detectability, we randomly selected stretches of 500m to be also surveyed on foot by two other observers (total 292 walked stretches, 146 km walked). We expected that body size of the carcass, road type, presence of scavengers and weather conditions to be the main drivers influencing the carcass persistence times, but their relative importance was unknown. We also expected detectability to be highly dependent on body size. Overall, we recorded low median persistence times (one day) and low detectability (<10%) for all vertebrates. The results indicate that body size and landscape cover (as a surrogate of scavengers’ presence) are the major drivers of carcass persistence. Detectability was lower for animals with body mass less than 100g when compared to carcass with higher body mass. We estimated that our recorded mortality rates underestimated actual values of mortality by 2–10 fold. Although persistence times were similar to previous studies, the detectability rates here described are very different from previous studies. The results suggest that detectability is the main source of bias across WVC studies. Therefore, more than persistence times, studies should carefully account for differing detectability when comparing WVC studies. 相似文献
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Ana Paula de Torres Santos José Eduardo Levi Marcilio Figueiredo Lemos Samira Julien Calux Isabel Takano Oba Regina Célia Moreira 《Memórias do Instituto Oswaldo Cruz》2016,111(2):134-140
This study aimed to standardise an in-house real-time polymerase chain reaction
(rtPCR) to allow quantification of hepatitis B virus (HBV) DNA in serum or plasma
samples, and to compare this method with two commercial assays, the Cobas Amplicor
HBV monitor and the Cobas AmpliPrep/Cobas TaqMan HBV test. Samples from 397 patients
from the state of São Paulo were analysed by all three methods. Fifty-two samples
were from patients who were human immunodeficiency virus and hepatitis C virus
positive, but HBV negative. Genotypes were characterised, and the viral load was
measure in each sample. The in-house rtPCR showed an excellent success rate compared
with commercial tests; inter-assay and intra-assay coefficients correlated with
commercial tests (r = 0.96 and r = 0.913, p < 0.001) and the in-house test showed
no genotype-dependent differences in detection and quantification rates. The in-house
assay tested in this study could be used for screening and quantifying HBV DNA in
order to monitor patients during therapy. 相似文献