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11.
The blue wildebeest (Connochaetes taurinus) is distributed throughout southern and east Africa while the black wildebeest (Connochaetes gnou) is endemic to South Africa and was driven to near extinction in the early 1900s due to hunting pressure and disease outbreaks. Extensive translocation of both species throughout South Africa is threatening the genetic integrity of blue and black wildebeest. To effectively manage these species, genetic tools that can be used to detect hybrid individuals, identify genetically unique subpopulations and determine the levels of genetic diversity are required. In this study, 11 microsatellite markers were developed for wildebeest through next-generation sequencing. The microsatellite loci displayed 2.00–4.14 alleles, unbiased heterozygosity values ranged from 0.32 to 0.60 and observed heterozygosity values ranged from 0.26 to 0.52. The comparatively high level of polymorphism observed in the microsatellite markers indicates that these markers can contribute significantly to our knowledge of population genetic structure, relatedness, genetic diversity and hybridization in these species.  相似文献   
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Arbuscular mycorrhizal fungi (AMF) are important members of the plant microbiome. They are obligate biotrophs that colonize the roots of most land plants and enhance host nutrient acquisition. Many AMF themselves harbor endobacteria in their hyphae and spores. Two types of endobacteria are known in Glomeromycota: rod-shaped Gram-negative Candidatus Glomeribacter gigasporarum, CaGg, limited in distribution to members of the Gigasporaceae family, and coccoid Mollicutes-related endobacteria, Mre, widely distributed across different lineages of AMF. The goal of the present study is to investigate the patterns of distribution and coexistence of the two endosymbionts, CaGg and Mre, in spore samples of several strains of Gigaspora margarita. Based on previous observations, we hypothesized that some AMF could host populations of both endobacteria. To test this hypothesis, we performed an extensive investigation of both endosymbionts in G. margarita spores sampled from Cameroonian soils as well as in the Japanese G. margarita MAFF520054 isolate using different approaches (molecular phylotyping, electron microscopy, fluorescence in situ hybridization and quantitative real-time PCR). We found that a single AMF host can harbour both types of endobacteria, with Mre population being more abundant, variable and prone to recombination than the CaGg one. Both endosymbionts seem to retain their genetic and lifestyle peculiarities regardless of whether they colonize the host alone or together. These findings show for the first time that fungi support an intracellular bacterial microbiome, in which distinct types of endobacteria coexist in a single cell.  相似文献   
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We report four cases of scalp white piedra (SWP) in Brazilian female children. Morphological and physiological approaches gave inconsistent results for identifying Trichosporon to species level, while the sequencing of the intergenic spacer 1 region of ribosomal DNA accurately identified the agent of SWP as T. inkin. These cases emphasize the occurrence of this species causing this type of infection. The molecular identification of the suspected agent is needed for appropriate epidemiological surveillance of superficial mycoses caused by Trichosporon species.  相似文献   
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X-linked adrenoleukodystrophy (X-ALD) is the most frequent peroxisomal disorder that is characterized by progressive demyelination of the white matter, adrenal insufficiency, and accumulation of very long-chain fatty acids in body fluid and tissues. This disorder is clinically heterogeneous with seven different phenotypes in male patients and five phenotypes in female carriers. An ultimate treatment for X-ALD is not available. Depending on the rate of the disease progression and the degree of an individual handicap, special needs and challenges vary greatly. The exact mechanisms underlying the pathophysiology of this multifactorial neurodegenerative disorder remains obscure. Previous studies has been related oxidative stress with the pathogenesis of several disease that affecting the central nervous system, such as neurodegenerative disease, epilepsy, multiple sclerosis, Alzheimer, and Parkinson diseases. In addition, oxidative damage has been observed in various in vivo and in vitro studies with inborn errors of metabolism, including X-ALD. In this context, this review is focused on oxidative stress in X-ALD, with emphasis on studies using biological samples from patients affected by this disease.  相似文献   
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Successful commercialization of microbial biocontrol agents, such as Metarhizium spp., is often constrained by poor drying survival and shelf life. Here, we hypothesized that culture age would influence endogenous arabitol, erythritol, mannitol and trehalose contents in M. brunneum mycelium and that elevated levels of these compounds would improve drying survival and shelf life of encapsulated mycelium coupled with enhanced fungal virulence against T. molitor larvae. We found that culture age significantly influenced endogenous arabitol and mannitol contents in mycelium with highest concentrations of 0.6?±?0.2 and 2.1?±?0.2 µg/mg after 72 h, respectively. Drying survival of encapsulated mycelium was independent of culture age and polyol content with 41.1?±?4.4 to 55.0?±?6.2%. Best shelf life was determined for biomass harvested after 72 h at all investigated storage temperatures with maximum values of 59.5?±?3.3% at 5 °C followed by 54.5?±?1.6% at 18 °C and 19.4?±?1.3% at 25 °C after 6 months. Finally, high fungal virulence against T. molitor larvae of 83.3?±?7.6 to 98.0?±?1.8% was maintained during storage of encapsulated mycelium for 12 months with larval mortalities being independent of culture age and polyol content. In conclusion, our findings indicate beneficial effects of endogenous polyols in improving shelf life of encapsulated mycelium and this may spur the successful development of microbial biocontrol agents in the future.  相似文献   
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Alzheimer's disease (AD) is characterized by severe neuronal loss as well as the accumulation of amyloid‐β (Aβ), which ultimately leads to plaque formation. Although there is now a general agreement that the aggregation of Aβ can be initiated by prion‐like seeding, the impact and functional consequences of induced Aβ deposits (Aβ seeding) on neurons still remain open questions. Here, we find that Aβ seeding, representing early stages of plaque formation, leads to a dramatic decrease in proliferation and neurogenesis in two APP transgenic mouse models. We further demonstrate that neuronal cell death occurs primarily in the vicinity of induced Aβ deposits culminating in electrophysiological abnormalities. Notably, environmental enrichment and voluntary exercise not only revives adult neurogenesis and reverses memory deficits but, most importantly, prevents Aβ seeding by activated, phagocytic microglia cells. Our work expands the current knowledge regarding Aβ seeding and the consequences thereof and attributes microglia an important role in diminishing Aβ seeding by environmental enrichment.  相似文献   
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Summary Sections of human skin were processed according to the indirect immunofluorescence technique with a rabbit antiserum against human protein gene product 9.5 (PGP 9.5). Immunoreactivity was detected in intraepidermal and dermal nerve fibres and cells. The intraepidermal nerves were varicose or smooth with different diameters, running as single processes or branched, straight or bent, projecting in various directions and terminating in the stratum basale, spinosum or granulosum. The density of the intraepidermal nerves varied between the different skin areas investigated. PGP 9.5-containing axons of the lower dermis were found in large bundles. They separated into smaller axon bundles within the upper dermis, entering this portion of the skin perpendicular to the surface. Then they branched into fibres mainly arranged parallel to the epidermal-dermal junctional zone. However, the fibres en route to the epidermis traversed the upper dermis more or less perpendicularly. Furthermore, immunoreactive dermal nerve fibres were found in the Meissner corpuscles, the arrector pili muscles, hair follicles, around the eccrine and apocrine sweat glands and around certain blood vessels. Such fibres were also observed around most subcutaneous blood vessels, sometimes heavily innervating these structures. Numerous weakly-to-strongly PGP 9.5-immunoreactive cells were found both in the epidermis and in the dermis.  相似文献   
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