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41.
Although the dog breeding industry is common in many countries, the presence of antimicrobial resistant bacteria among pups in kennels has been infrequently investigated. This study was conducted to better understand the epidemiology of antimicrobial-resistant Escherichia coli isolates from kennel pups not treated with antimicrobials. We investigated susceptibilities to 11 antimicrobials, and prevalence of extended-spectrum β-lactamase (ESBL) in 86 faecal E. coli isolates from 43 pups in two kennels. Genetic relatedness among all isolates was assessed using pulsed-field gel electrophoresis (PFGE). Susceptibility tests revealed that 76% of the isolates were resistant to one or more of tested antimicrobials, with resistance to dihydrostreptomycin most frequently encountered (66.3%) followed by ampicillin (60.5%), trimethoprim-sulfamethoxazole (41.9%), oxytetracycline (26.7%), and chloramphenicol (26.7%). Multidrug resistance, defined as resistance against two or more classes of antimicrobials, was observed in 52 (60.5%) isolates. Three pups in one kennel harboured SHV-12 ESBL-producing isolates. A comparison between the two kennels showed that frequencies of resistance against seven antimicrobials and the variation in resistant phenotypes differed significantly. Analysis by PFGE revealed that clone sharing rates among pups of the same litters were not significantly different in both kennels (64.0% vs. 88.9%), whereas the rates among pups from different litters were significantly different between the two kennels (72.0% vs. 33.3%, P < 0.05). The pups in the two kennels had antimicrobial-resistant E. coli clones, including multidrug-resistant and ESBL-producing clones. It is likely that resistant and susceptible bacteria can clonally spread among the same and/or different litters thus affecting the resistance prevalence.  相似文献   
42.
A new type of natural pyrrhotite, orthorhombic 11C type (a = 6.892, b = 11.952, c = 5.744 x 11 angstroms), and the hexagonal 6C type (a = 6.89, c = 5.76 x 6 angstroms) are described. Their compositions are Fe(10)S(11) and Fe(11)S(12), respectively. Pyrrhotites stable in nature have essentially stoichiometric composition, Fe(n)-(l)S(n) (n>/=8), with the structures of n/2C type for n even and of nC type for n odd. The solid solutions between Fe(11)S(12) and Fe(10)S(11), and between Fe(10)S(11) and Fe(9)S(10) are considered metastable in nature.  相似文献   
43.
Temperature pervasively affects all cellular processes. In response to a rapid increase in temperature, all cells undergo a heat shock response, an ancient and highly conserved program of stress-inducible gene expression, to reestablish cellular homeostasis. In isolated cells, the heat shock response is initiated by the presence of misfolded proteins and therefore thought to be cell-autonomous. In contrast, we show that within the metazoan Caenorhabditis elegans, the heat shock response of somatic cells is not cell-autonomous but rather depends on the thermosensory neuron, AFD, which senses ambient temperature and regulates temperature-dependent behavior. We propose a model whereby this loss of cell autonomy serves to integrate behavioral, metabolic, and stress-related responses to establish an organismal response to environmental change.  相似文献   
44.
A new high-pressure polymorph with a modified spinel structure, beta-Mn(2)GeO(4), is stable in a pressure range intermediate between the field of the polymorph with the olivine structure and that of another high-pressure polymorph. Oxygen atoms are located approximately in cubic close packing with manganese and germanium atoms in octahedral and tetrahedral interstices, respectively, as in the spinel structure; however, germanium atoms form Ge(2)O(7) groups instead of isolated GeO(4) groups.  相似文献   
45.
46.
Winter cover crops increase the amount of indigenous arbuscular mycorrhizal fungi (AMF) in the soil, providing beneficial effects such as enhancement of phosphorus uptake by the subsequent crop. However, its impact on the AMF community structure is not well understood. In the present study, we aimed to reveal the effect of winter wheat cover cropping with no-till cultivation on the AMF community structures in soil and roots of the subsequent soybean. For this purpose, we conducted a field experiment consisting of two treatments, no-till soybean cultivation after winter wheat cover cropping (NTWC) and conventional soybean cultivation after winter fallow management as a control (CONT). At the flowering stage of soybean, higher AMF colonization of soybean roots was observed in the NTWC plots compared with the CONT plots. Additionally, aboveground biomass and phosphorus uptake of soybean in the NTWC plots were significantly higher than those in the CONT plots. Molecular community analyses based on PCR-denaturing gradient gel electrophoresis (DGGE) of AMF 18S rRNA genes indicated that the AMF community structures in the soil and soybean root of the NTWC plots were clearly different from those of the CONT plots. The DGGE profiles showed that the wheat cover cropping preferentially increased some phylotypes belonging to Glomeraceae and Claroideoglomeraceae. In addition, most of the phylotypes were characteristically observed in the subsequent soybean root of the NTWC plots, strongly suggesting that these phylotypes colonizing the cover crop wheat were taken over by the subsequent soybean. Our study revealed the significant effect of winter cover cropping with no-till cultivation on the structure of AMF community colonizing the subsequent soybean.  相似文献   
47.
Paddy and Water Environment - There has been a growing global interest in urban agriculture that contributes to the well-being of urban dwellers by providing various ecosystem services. Focusing on...  相似文献   
48.
We determined the analgesic effects of epidural administration of either bupivacaine at 62.5, 125, 250, and 500 micrograms/kg; buprenorphine at 5 and 10 micrograms/kg; and the combination of bupivacaine at 125 micrograms/kg and buprenorphine at 5 or 10 micrograms/kg, using the tail flick (TF) and colorectal distension (CD) tests in rats and compared the results with those obtained using morphine at 100 micrograms/kg. In both the TF and CD tests, all doses of bupivacaine alone produced potent anti-nociceptive effects, although the effect rapidly diminished after 20-30 min of administration. The administration of buprenorphine at 10 and 5 micrograms/kg produced mild to moderate anti-nociceptive effects in both the TF and CD tests, and the effects were relatively constant throughout the 2-h experimental period. Combinations of 5 or 10 micrograms/kg of buprenorphine with 125 mg/kg of bupivacaine produced a significantly higher percentage of maximum possible analgesic effect (%MPE) than that of the calculated additive effect of each drug alone in the TF and CD tests. The analgesic effect of this combination was similar to that of morphine. Minimal ataxia was observed in rats administered this combination.  相似文献   
49.
The effects of interferon (IFN)-gamma induced by virus infection on eosinophil reaction in allergic airway inflammation are not yet clear. We investigated the effects of lactic dehydrogenase virus (LDV) infection, which increases IFN -gamma production with no viral infection or replication in respiratory epithelium, on allergic airway hypersensitivity. LDV infection suppressed antigen-induced eosinophil recruitment into the airway in sensitized mice. IL -5 gene expression in bronchoalveolar lavage (BAL) cells was significantly suppressed in LDV -infected mice compared with uninfected controls. The numbers of total T cells and CD 4+ T cells were significantly reduced in LDV -infected mice compared with controls. The present results suggested that the increase in production of IFN -gamma by viral infection suppresses the eosinophil reaction, and this suppressive effect may be mediated by inhibition of the recruitment of CD 4+ T cell and IL -5 production.  相似文献   
50.
内蒙古红花尔基鸟类群落与植被类型相互关系研究   总被引:4,自引:0,他引:4  
调查了内蒙北部红花尔基夏季鸟类群落,一共记录了28种鸟类。在每个实验地取5个10m×10m的样方进行植被调查。利用线性回归方程来确定植被郁闭度和鸟类数量和鸟类密度的关系。分析结果显示鸟类数量和鸟类密度的变化及鸟类群落的形成是随着森林类型和总植物量而变化。鸟类数量和密度都随总植物量的降低而减少。鸟类群落的相似性在繁殖时期非常低,在同一分类簇中,最大相似性不超过0.65。这表明鸟类群落间种类的构成存在着显著差异。鸟类的繁殖密度与森林的生长阶段具有密切的关系,一般情况下,从稀疏的草原生态系统到顶级生态系统鸟类的密度呈现逐渐增加的趋势。图3表4参21。  相似文献   
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