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31.
32.
Salmonella typhimurium was cultured in presence or absence of norepinephrine in conditioned media. Two conditioned media containing bovine and pig serum were prepared. Supplementation of fresh cultures with norepinephrine (5 x 10(-5) M per mL of medium) resulted in ten-fold increase in growth as compared to controls. No significant difference in growth of organisms in media containing bovine and pig serum was observed. Growth was more in culture incubated under shaking condition than in non-shaking condition. Enterotoxin production increased by two to eight-folds in the medium supplemented with norepinephrine. 相似文献
33.
Asma Haque Tayyaba Shaheen Tahsin Gulzar Mahmood ur Rahman Fatima Jalal Summera Sattar Beenish Ehsan Zafar Iqbal Muhammad Younas 《Bioinformation》2014,10(6):371-377
Wheat is a vital dietary component for human health and widely consumed in the world. Wheat rusts are dangerous pathogens
and contribute serious threat to its production. In present study, PCR-Based DNA Markers were employed to check the rust
resistance genes among 20 wheat genotypes and 22 markers were amplified. NTSYS-pc 2.2 was used to calculate genetic diversity
and Nei and Li''s coefficients ranged from 0.55 to 0.95. Cluster analysis was obtained using UPGMA (Unweighted Pair Group
Method of Arithmetic Average) algorithm. Maximum no. of genes (23) was amplified from TW-760010 genotype whereas
minimum no of genes (14) were amplified from TW-76005 genotype. The data gained from present study open up new ways to
produce new varieties by breeding rust resistant germplasm to avoid the economic and food loss and varieties with improved
characteristics. 相似文献
34.
Khaled M. Abdel Rahman Marek Barta Ľudovít Cagáň 《Central European Journal of Biology》2010,5(4):472-480
We tested the combined effect of the fungus Beauveria bassiana and the microsporidium Nosema pyrausta on the European corn borer larvae, Ostrinia nubilalis, in the laboratory. The first instar of O. nubilalis larvae was the most sensitive to the B. bassiana infection followed by the fifth, second, third, and fourth instar (LC50s were 4.91, 6.67, 7.13, 9.15, and 6.51 × 105 conidia/ml for the first to fifth instars, respectively). Mortality of each instar increases positively with concentration
of conidia. When B. bassiana and N. pyrausta were used in combination, mortality increased significantly in all instars. Relative to the B. bassiana treatment alone, the B. bassiana + N. pyrausta treatment decreased the LC50s by 42.16%, 37.63%, 21.60%, 27.11%, and 33.95% for the first to fifth instars, respectively. The combined effects of the
two pathogens were mostly additive. However, at the two highest concentrations the pathogens interacted synergistically in
the first and second instar. Individuals that survived the B. bassiana and B. bassiana + N. pyrausta treatments and developed into adults had significantly shorter lifespans and females oviposited fewer eggs than non-exposed
insects. The effects on the longevity and the egg production were most pronounced at high concentration of B. bassiana conidia. 相似文献
35.
36.
The potential of Mg(x)Co(2-)(x)O(2) as heterogeneous reusable catalyst in transesterification of palm oil to methyl ester was investigated. The catalyst was prepared via co-precipitation of the metal hydroxides at different Mg-Co ratios. Mg(1.7)Co(0.3)O(2) catalyst was more active than Mg(0.3)Co(1.7)O(2) in the transesterification of palm oil with methanol. The catalysts calcined at temperature 300 °C for 4 h resulted in highly active oxides and the highest transesterification of 90% was achieved at methanol/oil molar ratio of 9:1, catalyst loading of 5.00 wt.%, reaction temperature of 150 °C and reaction time of 2 h. The catalyst could easily be removed from reaction mixture, but showed 50% decrease in activity when reused due to leaching of active sites. 相似文献
37.
Rebecca S. Pelc Jennifer C. McClure Simran J. Kaur Khandra T. Sears M. Sayeedur Rahman Shane M. Ceraul 《PloS one》2015,10(3)
Peptide Nucleic Acids (PNAs) are single-stranded synthetic nucleic acids with a pseudopeptide backbone in lieu of the phosphodiester linked sugar and phosphate found in traditional oligos. PNA designed complementary to the bacterial Shine-Dalgarno or start codon regions of mRNA disrupts translation resulting in the transient reduction in protein expression. This study examines the use of PNA technology to interrupt protein expression in obligate intracellular Rickettsia sp. Their historically intractable genetic system limits characterization of protein function. We designed PNA targeting mRNA for rOmpB from Rickettsia typhi and rickA from Rickettsia montanensis, ubiquitous factors important for infection. Using an in vitro translation system and competitive binding assays, we determined that our PNAs bind target regions. Electroporation of R. typhi and R. montanensis with PNA specific to rOmpB and rickA, respectively, reduced the bacteria’s ability to infect host cells. These studies open the possibility of using PNA to suppress protein synthesis in obligate intracellular bacteria. 相似文献
38.
Respiratory Viruses Associated Hospitalization among Children Aged <5 Years in Bangladesh: 2010-2014
Nusrat Homaira Stephen P. Luby Kamal Hossain Kariul Islam Makhdum Ahmed Mustafizur Rahman Ziaur Rahman Repon C. Paul Mejbah Uddin Bhuiyan W. Abdullah Brooks Badrul Munir Sohel Kajal Chandra Banik Marc-Alain Widdowson Melisa Willby Mahmudur Rahman Joseph Bresee Katharine-Sturm Ramirez Eduardo Azziz-Baumgartner 《PloS one》2016,11(2)
Background
We combined hospital-based surveillance and health utilization survey data to estimate the incidence of respiratory viral infections associated hospitalization among children aged < 5 years in Bangladesh.Methods
Surveillance physicians collected respiratory specimens from children aged <5 years hospitalized with respiratory illness and residing in the primary hospital catchment areas. We tested respiratory specimens for respiratory syncytial virus, parainfluenza viruses, human metapneumovirus, influenza, adenovirus and rhinoviruses using rRT-PCR. During 2013, we conducted a health utilization survey in the primary catchment areas of the hospitals to determine the proportion of all hospitalizations for respiratory illness among children aged <5 years at the surveillance hospitals during the preceding 12 months. We estimated the respiratory virus-specific incidence of hospitalization by dividing the estimated number of hospitalized children with a laboratory confirmed infection with a respiratory virus by the population aged <5 years of the catchment areas and adjusted for the proportion of children who were hospitalized at the surveillance hospitals.Results
We estimated that the annual incidence per 1000 children (95% CI) of all cause associated respiratory hospitalization was 11.5 (10–12). The incidences per 1000 children (95% CI) per year for respiratory syncytial virus, parainfluenza, adenovirus, human metapneumovirus and influenza infections were 3(2–3), 0.5(0.4–0.8), 0.4 (0.3–0.6), 0.4 (0.3–0.6), and 0.4 (0.3–0.6) respectively. The incidences per 1000 children (95%CI) of rhinovirus-associated infections among hospitalized children were 5 (3–7), 2 (1–3), 1 (0.6–2), and 3 (2–4) in 2010, 2011, 2012 and 2013, respectively.Conclusion
Our data suggest that respiratory viruses are associated with a substantial burden of hospitalization in children aged <5 years in Bangladesh. 相似文献39.
Computational fluid dynamics as a tool for testing functional and ecological hypotheses in fossil taxa 下载免费PDF全文
Imran A. Rahman 《Palaeontology》2017,60(4):451-459
Computational fluid dynamics is a method for simulating fluid flows that has been widely used in engineering for decades, and which also has applications for studying function and ecology in fossil taxa. However, despite the possible benefits of this approach, computational fluid dynamics has been used only rarely in palaeontology to date. The theoretical basis underlying the technique is outlined and the main steps involved in carrying out computer simulations of fluid flows are detailed. I also describe previous studies that have applied the method to fossils and discuss their potential for informing future research directions in palaeontology. Computational fluid dynamics can enable large‐scale comparative analyses, as well as exacting tests of hypotheses related to the function and ecology of ancient organisms. In this way, it could transform our understanding of many extinct fossil groups. 相似文献
40.
Raja Noor Zaliha Raja Abd Rahman Thean Chor Leow Abu Bakar Salleh Mahiran Basri 《BMC microbiology》2007,7(1):77