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81.
Six clones of monoclonal antibodies (Mabs) to fowl adenovirus (FAV) serotype 1 were produced. All Mabs reacted positively by enzyme-linked immunosorbent assay. Three Mabs recognized the putative 100-kD hexon protein and reacted to serotype 1 specifically by western blot analysis but did not react to other FAV serotypes (2, 3, 4, 5, 6, 7, and 8a). These Mabs will be useful for immunodiagnosis of FAV serotype 1 infection in chickens with gizzard erosion and in further research studies involving the genomes and proteins of FAV serotype 1.  相似文献   
82.
Three beagle dogs were inoculated with mice spleen/liver homogenate infected with Ehrlichia species detected from Ixodes ovatus (EIO) and one dog was used as a control. All three infected dogs did not show clinical signs of disease except for mild pyrexia throughout the 41-day study period. Splenomegaly was observed from Day 7 post-inoculation (p.i.) in two of the dogs. Hematological and biochemical abnormalities included mild thrombocytopenia, hypoproteinaemia, hypoalbuminaemia and increased C-reactive protein values. One of the dogs' splenic aspirate sample was PCR-positive for Ehrlichia Day 7 p.i. and another dogs' blood and bone marrow aspirate sample was PCR-positive Day 41 p.i. Sequence analysis of the PCR products showed 100% homology with the 16SrRNA partial gene sequence of Ehrlichia sp. HF565. Antibody titers to EIO were observed in all three experimentally infected dogs starting from the first week p.i. and cross-reactivity with Ehrlichia canis was detectable in one of the dogs starting Day 7 p.i. These data suggest that infection of dogs with EIO is possible, though is probably of low pathogenic importance. Cross-reactivity of EIO infected dog serum with E. canis raises the likelihood of false E. canis seropositive dogs.  相似文献   
83.
Keratinocyte differentiation-associated protein, Kdap, is a recently identified small secretory protein that may act as a soluble regulator for the cornification and/or desquamation of keratinocytes. To clarify the role of Kdap in the terminal differentiation of keratinocytes, detailed in situ localisation of Kdap was studied using canine skin with normal, hyperplastic and neoplastic epidermis. In normal canine trunk skin, Kdap was expressed by granular keratinocytes, with polarity to the apical side of the cells, suggesting that canine Kdap is present in lamellar granules, as in humans. Expression of Kdap was widespread in the spinous layers in hyperplastic epidermis, but was undetectable in squamous cell carcinomas. These findings suggest that Kdap is closely related to the delay of terminal differentiation and/or release of cells in hyperplastic epidermis.  相似文献   
84.
Carbon fibers have excellent physicochemical and electrical properties. Vapor-grown carbon fibers are a type of carbon fibers that have a multi-walled carbon tube structure with a high aspect ratio. The representative vapor-grown carbon fiber, VGCFTM-H, is extremely strong and stable and has superior thermal and electrical conductivity. Because some high-aspect-ratio multi-walled carbon nanotubes (MWCNTs) have been reported to have toxic and carcinogenic effects in the lungs of rodents, we performed a 13-week lung toxicity study using VGCFTM-H in comparison with one of MWCNTs, MWNT-7, in rats. Male and female F344 rats were intratracheally administered VGCFTM-H at doses of 0.2, 0.4, and 0.8 mg/kg bw or MWNT-7 at doses of 0.4 and 0.8 mg/kg bw once a week for 8 weeks and then up to week 13 without treatment. The lung burden was equivalent in the VGCFTM-H and MWNT-7 groups; however, the lung weight had increased and the inflammatory and biochemical parameters in the broncho-alveolar lavage fluid and histopathological parameters, including inflammatory cell infiltration, alveolar type II cells proliferation, alveolar fibrosis, pleural fibrosis, lung mesothelium proliferation, and diaphragm fibrosis, were milder in the VGCFTM-H group than in the MWNT-7 group. In addition, the proliferating cell nuclear antigen (PCNA)-positive index in the visceral and pleural mesothelium was significantly higher in the MWNT-7 group than in the controls, but not in the VGCFTM-H group. Thus, the results of this study indicate that the lung and pleural toxicities of VGCFTM-H were less than those of MWNT-7.  相似文献   
85.
86.
It has recently been shown that neurokinin B, a tachykinin, is associated with GnRH pulse generation in sheep and goats. The aim of the present study was to clarify the role of tachykinin receptors in the control of LH secretion in rats. To this end, we evaluated the effect of CS-003, an antagonist for all three neurokinin receptors (NK1, NK2 and NK3 receptors), on pulsatile LH secretion in both sexes of rats with different routes of administration. Both oral and third ventricular administration of CS-003 suppressed LH secretion in both sexes of gonadectomized animals. Furthermore, intact male rats with oral administration of CS-003 showed decreased serum testosterone levels, which might be due to suppressed LH secretion. None of the three subtype-specific neurokinin receptor antagonists showed a significant effect on LH secretion in ovariectomized rats when each antagonist was singly administered. The present results suggest that neurokinins play a role in the control of pulsatile GnRH/LH secretion via multiple neurokinin receptors in both male and female rats.  相似文献   
87.
The stratum corneum of epidermis is an essential barrier against the external environment and water loss. This study aimed to develop an organotypic culture model that targets the reconstruction of the stratum corneum using canine keratinocyte-derived CPEK cells. The CPEK cells cultured at the air-liquid interface became stratified and formed a stratum corneum-like layer on stratum spinosum- and stratum granulosum-like layers. The CPEK cells in the stratum granulosum-like layer expressed the cornified cell envelope (CCE)-related proteins loricrin and keratinocyte differentiation-associated protein. Organotypically cultured CPEK cells were considered to form a CCE at the stratum granulosum-like layer, allowing the formation of a stratum corneum-like layer. The organotypic culture of CPEK cells could be useful for studying the barrier function of canine stratum corneum.  相似文献   
88.
The first chordates appear in the fossil record at the time of the Cambrian explosion, nearly 550 million years ago. The modern ascidian tadpole represents a plausible approximation to these ancestral chordates. To illuminate the origins of chordate and vertebrates, we generated a draft of the protein-coding portion of the genome of the most studied ascidian, Ciona intestinalis. The Ciona genome contains approximately 16,000 protein-coding genes, similar to the number in other invertebrates, but only half that found in vertebrates. Vertebrate gene families are typically found in simplified form in Ciona, suggesting that ascidians contain the basic ancestral complement of genes involved in cell signaling and development. The ascidian genome has also acquired a number of lineage-specific innovations, including a group of genes engaged in cellulose metabolism that are related to those in bacteria and fungi.  相似文献   
89.
Diploid yeast cells repeatedly polarize and bud from their poles, probably because of highly stable marks of unknown composition. Here, Rax2, a membrane protein, was shown to behave as such a mark. The Rax2 protein itself was inherited immutably at the cell cortex for multiple generations, and Rax2 was shown to have a half-life exceeding several generations. The persistent inheritance of cortical protein markers would provide a means to couple a cell's history to the future development of a precise morphogenetic form.  相似文献   
90.
Agricultural soil is a major source of nitrous oxide (N2O), and the application of nitrogen and soil drainage are important factors affecting N2O emissions. This study tested the use of polymer-coated urea (PCU) and polymer-coated urea with the nitrification inhibitor dicyandiamide (PCUD) as potential mitigation options for N2O emissions in an imperfectly drained, upland converted paddy field. Fluxes of N2O and methane (CH4), ammonia oxidation potential, and ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) abundances were monitored after the application of PCU, PCUD, and urea to upland soil. The results showed that urea application increased the ammonia oxidation potential and AOB and AOA abundances; however, the increase rate of AOB (4.6 times) was much greater than that of AOA (1.8 times). These results suggested that both AOB and AOA contributed to ammonia oxidation after fertilizer application, but the response of AOB was greater than AOA. Although PCU and PCUD had lower ammonia oxidation potential compared to urea treatment, they were not effective in reducing N2O emissions. Large episodic N2O emissions (up to 1.59 kg N ha?1 day?1) were observed following heavy rainfall 2 months after basal fertilizer application. The episodic N2O emissions accounted for 55–80 % of total N2O emissions over the entire monitoring period. The episodic N2O emissions following heavy rainfall would be a major source of N2O in poorly drained agricultural fields. Cumulative CH4 emissions ranged from ?0.017 to ?0.07 kg CH4 ha?1, and fertilizer and nitrification inhibitor application did not affect CH4 oxidation.  相似文献   
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