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51.
Souma?la Pagabeleguem Geoffrey Gimonneau Momar Talla Seck Marc J. B. Vreysen Baba Sall Jean-Baptiste Rayaissé Issa Sidibé Jérémy Bouyer Sophie Ravel 《PLoS neglected tropical diseases》2016,10(2)
Background
The Government of Senegal has embarked several years ago on a project that aims to eradicate Glossina palpalis gambiensis from the Niayes area. The removal of the animal trypanosomosis would allow the development more efficient livestock production systems. The project was implemented using an area-wide integrated pest management strategy including a sterile insect technique (SIT) component. The released sterile male flies originated from a colony from Burkina Faso.Methodology/Principal Findings
Monitoring the efficacy of the sterile male releases requires the discrimination between wild and sterile male G. p. gambiensis that are sampled in monitoring traps. Before being released, sterile male flies were marked with a fluorescent dye powder. The marking was however not infallible with some sterile flies only slightly marked or some wild flies contaminated with a few dye particles in the monitoring traps. Trapped flies can also be damaged due to predation by ants, making it difficult to discriminate between wild and sterile males using a fluorescence camera and / or a fluorescence microscope. We developed a molecular technique based on the determination of cytochrome oxidase haplotypes of G. p. gambiensis to discriminate between wild and sterile males. DNA was isolated from the head of flies and a portion of the 5’ end of the mitochondrial gene cytochrome oxidase I was amplified to be finally sequenced. Our results indicated that all the sterile males from the Burkina Faso colony displayed the same haplotype and systematically differed from wild male flies trapped in Senegal and Burkina Faso. This allowed 100% discrimination between sterile and wild male G. p. gambiensis.Conclusions/Significance
This tool might be useful for other tsetse control campaigns with a SIT component in the framework of the Pan-African Tsetse and Trypanosomosis Eradication Campaign (PATTEC) and, more generally, for other vector or insect pest control programs. 相似文献52.
Absence of replication of porcine endogenous retrovirus and porcine lymphotropic herpesvirus type 1 with prolonged pig cell microchimerism after pig-to-baboon xenotransplantation 下载免费PDF全文
Issa NC Wilkinson RA Griesemer A Cooper DK Yamada K Sachs DH Fishman JA 《Journal of virology》2008,82(24):12441-12448
Porcine endogenous retrovirus (PERV), porcine cytomegalovirus (PCMV), and porcine lymphotropic herpesvirus (PLHV) are common porcine viruses that may be activated with immunosuppression for xenotransplantation. Studies of viral replication or transmission are possible due to prolonged survival of xenografts in baboon recipients from human decay-accelerating factor transgenic or alpha-1,3-galactosyltransferase gene knockout miniature swine. Ten baboons underwent xenotransplantation with transgenic pig organs. Graft survival was 32 to 179 days. Recipient serial samples of peripheral blood mononuclear cells (PBMC) and plasma were analyzed for PCMV, PERV, and PLHV-1 nucleic acids and viral replication using quantitative PCR assays. The PBMC contained PERV proviral DNA in 10 animals, PLHV-1 DNA in 6, and PCMV in 2. PERV RNA was not detected in any PBMC or serum samples. Plasma PLHV-1 DNA was detected in one animal. Pig cell microchimerism (pig major histocompatibility complex class I and pig mitochondrial cytochrome c oxidase subunit II sequences) was present in all recipients with detectable PERV or PLHV-1 (85.5%). Productive infection of PERV or PLHV-1 could not be demonstrated. The PLHV-1 viral load did not increase in serum over time, despite prolonged graft survival and pig cell microchimerism. There was no association of viral loads with the nature of exogenous immune suppression. In conclusion, PERV provirus and PLHV-1 DNA were detected in baboons following porcine xenotransplantation. Viral detection appeared to be due to persistent pig cell microchimerism. There was no evidence of productive infection in recipient baboons for up to 6 months of xenograft function. 相似文献
53.
Rahul Aggarwal Robert W. Yeh Issa J. Dahabreh Sarah E. Robertson Rishi K. Wadhera 《PLoS medicine》2022,19(10)
BackgroundUS policymakers are debating whether to expand the Medicare program by lowering the age of eligibility. The goal of this study was to determine the association of Medicare eligibility and enrollment with healthcare access, affordability, and financial strain from medical bills in a contemporary population of low- and higher-income adults in the US.Methods and findingsWe used cross-sectional data from the National Health Interview Survey (2019) to examine the association of Medicare eligibility and enrollment with outcomes by income status using a local randomization-based regression discontinuity approach. After weighting to account for survey sampling, the low-income group consisted of 1,660,188 adults age 64 years and 1,488,875 adults age 66 years, with similar baseline characteristics, including distribution of sex (59.2% versus 59.7% female) and education (10.8% versus 12.5% with bachelor’s degree or higher). The higher-income group consisted of 2,110,995 adults age 64 years and 2,167,676 adults age 66 years, with similar distribution of baseline characteristics, including sex (40.0% versus 49.4% female) and education (41.0% versus 41.6%). The share of adults age 64 versus 66 years enrolled in Medicare differed within low-income (27.6% versus 87.8%, p < 0.001) and higher-income groups (8.0% versus 85.9%, p < 0.001). Medicare eligibility at 65 years was associated with a decreases in the percentage of low-income adults who delayed (14.7% to 6.2%; −8.5% [95% CI, −14.7%, −2.4%], P = 0.007) or avoided medical care (15.5% to 5.9%; −9.6% [−15.9%, −3.2%], P = 0.003) due to costs, and a larger decrease in the percentage who were worried about (66.5% to 51.1%; −15.4% [−25.4%, −5.4%], P = 0.003) or had problems (33.9% to 20.6%; −13.3% [−23.0%, −3.6%], P = 0.007) paying medical bills. In contrast, there were no significant associations between Medicare eligibility and measures of cost-related barriers to medication use. For higher-income adults, there was a large decrease in worrying about paying medical bills (40.5% to 27.5%; −13.0% [−21.4%, −4.5%], P = 0.003), a more modest decrease in avoiding medical care due to cost (3.5% to 0.6%; −2.9% [−5.3%, −0.5%], P = 0.02), and no significant association between eligibility and other measures of healthcare access and affordability. All estimates were stronger when examining the association of Medicare enrollment with outcomes for low and higher-income adults. Additional analyses that adjusted for clinical comorbidities and employment status were largely consistent with the main findings, as were analyses stratified by levels of educational attainment. Study limitations include the assumption adults age 64 and 66 would have similar outcomes if both groups were eligible for Medicare or if eligibility were withheld from both.ConclusionsMedicare eligibility and enrollment at age 65 years were associated with improvements in healthcare access, affordability, and financial strain in low-income adults and, to a lesser extent, in higher-income adults. Our findings provide evidence that lowering the age of eligibility for Medicare may improve health inequities in the US.Rahul Aggarwal and colleagues explore the association of Medicare eligibility and enrollment with health care access, affordability, and financial strain from medical bills in low- and higher-income adults in the US. 相似文献
54.
Histone deacetylase inhibitor activity in royal jelly might facilitate caste switching in bees 总被引:2,自引:0,他引:2
Spannhoff A Kim YK Raynal NJ Gharibyan V Su MB Zhou YY Li J Castellano S Sbardella G Issa JP Bedford MT 《EMBO reports》2011,12(3):238-243
Worker and queen bees are genetically indistinguishable. However, queen bees are fertile, larger and have a longer lifespan than their female worker counterparts. Differential feeding of larvae with royal jelly controls this caste switching. There is emerging evidence that the queen-bee phenotype is driven by epigenetic mechanisms. In this study, we show that royal jelly--the secretion produced by the hypopharyngeal and mandibular glands of worker bees--has histone deacetylase inhibitor (HDACi) activity. A fatty acid, (E)-10-hydroxy-2-decenoic acid (10HDA), which accounts for up to 5% of royal jelly, harbours this HDACi activity. Furthermore, 10HDA can reactivate the expression of epigenetically silenced genes in mammalian cells. Thus, the epigenetic regulation of queen-bee development is probably driven, in part, by HDACi activity in royal jelly. 相似文献
55.
We previously demonstrated that expression of IGF-II modulates the routing of cathepsin D in MCF-7 cells. In our present study, we transfected antisense IGF-II into IGF-II secreting MCF-7 cells to test the hypothesis that blocking IGF-II may reduce the secretion of cathepsin D in breast cancer cells. The concentration of IGF-II in media conditioned by the antisense clone was reduced to almost undetectable levels. Likewise, Northern blotting analysis revealed that IGF-II mRNA was nearly undetectable in the antisense transfected cells. Metabolic labeling experiments performed with 10 mM mannose 6-phosphate present in the medium to block reuptake of lysosomal enzymes demonstrated that cathepsin D secretion was dramatically reduced. Similarly, a significant reduction in cathepsin D was observed when conditioned media and cell extracts were examined by Western blotting after a 48 h incubation. No changes in cathepsin D mRNA in antisense cells were detected by Northern blot analysis. We conclude that endogenous IGF-II may modulate the routing of cathepsin D by interfering with receptor trafficking in MCF-7 cells, and that this modulation is reversible. Abnormally high levels of IGF-II may alter this homeostasis, conferring on breast cancer cells an advantageous mechanism that promotes rapid growth, and may facilitate metastasis. 相似文献
56.
57.
Chunlei Jin Taichun Qin Michelle Craig Barton Jaroslav Jelinek Jean-Pierre J Issa 《Epigenetics》2015,10(11):1006-1013
Oxidation of 5-methylcytosine by TET family proteins can induce DNA replication-dependent (passive) DNA demethylation and base excision repair (BER)-based (active) DNA demethylation. The balance of active vs. passive TET-induced demethylation remains incompletely determined. In the context of large scale DNA demethylation, active demethylation may require massive induction of the DNA repair machinery and thus compromise genome stability. To study this issue, we constructed a tetracycline-controlled TET-induced global DNA demethylation system in HEK293T cells. Upon TET overexpression, we observed induction of DNA damage and activation of a DNA damage response; however, BER genes are not upregulated to promote DNA repair. Depletion of TDG (thymine DNA glycosylase) or APEX1 (apurinic/apyrimidinic endonuclease 1), two key BER enzymes, enhances rather than impairs global DNA demethylation, which can be explained by stimulated proliferation. By contrast, growth arrest dramatically blocks TET-induced global DNA demethylation. Thus, in the context of TET-induction in HEK293T cells, the DNA replication-dependent passive mechanism functions as the predominant pathway for global DNA demethylation. In the same context, BER-based active demethylation is markedly restricted by limited BER upregulation, thus potentially preventing a disastrous DNA damage response to extensive active DNA demethylation. 相似文献
58.
59.
Influence of selenium on toxicity of some heavy metals in the green algaScenedesmus obliquus 总被引:1,自引:0,他引:1
The green alga Scenedesmus obliquus was incubated with heavy metals (Cd2+, Zn2+, Mn2+, Ni2+) with and without selenium. S. obliquus exhibited higher rates of growth and some metabolic activities in cultures containing 0.1 mmol/L Se than those only containing the heavy metals. The positive effect of Se was found with all metals but was negligible with Mn2+. 相似文献
60.
Effects of the inoculation of cyanobacteria on the microstructure and the structural stability of a tropical soil 总被引:3,自引:0,他引:3
Oumarou Malam Issa Christian Défarge Yves Le Bissonnais Béatrice Marin Odile Duval Ary Bruand Luigi Paolo D’Acqui Sofie Nordenberg Marcus Annerman 《Plant and Soil》2007,290(1-2):209-219
Cyanobacteria are widespread photosynthetic microorganisms among which some are able to fix atmospheric nitrogen. We investigated
the impact of indigenous cyanobacteria strains (Nostoc) inoculation on physical characteristics of poorly aggregated soils from Guquka (Eastern Cape, South Africa). The soil aggregates
(3–5 mm) were arranged into a layer of 10–20 mm thick, and sprayed with cyanobacteria solution. Subsequently the inoculated
and un-inoculated samples were incubated (30°C, 80% humidity, continuous illumination at 100 μmol m−2 s−1). Their micromorphological characteristics and aggregate stability were investigated, after 1, 2, 3, 4 and 6 weeks of incubation,
by using high resolution Cryo-SEM and aggregate breakdown tests.
Micromorphological investigations revealed that the surface of un-inoculated samples remained uncovered, while the inoculated
samples were partially covered by cyanobacteria material after one week of incubation. A dense superficial network of cyanobacterial
filaments and extracellular polymer secretions (EPS) covered their surface after 4 and 6 weeks of incubation. Organo-mineral
aggregates comprising cyanobacterial filaments and EPS were observed after 6 weeks of incubation. The results of aggregate
breakdown tests showed no significant difference between un-inoculated samples after 1, 2, 3, 4 or 6 weeks, while they revealed
improvement of aggregate stability for inoculated samples. The improvement of aggregate stability appeared in a short while
following inoculation and increased gradually with time and cyanobacteria growth. The increase in aggregate stability is likely
related to the changes induced in micromorphological characteristics by cyanobacterial filaments and EPS. It reflects the
effect of coating, enmeshment, binding and gluing of aggregates and isolated mineral particles by cyanobacteria material.
Our study presents new data demonstrating the improvement of soil physical quality in a few weeks after cyanobacteria inoculation.
The interaction of the inocula and other biotic components is worthy of study before field application of cyanobacteria. 相似文献