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71.
We investigated the effect of group culture on bovine embryo development, and also investigated the effect of embryo-culture conditioned medium on developmental competence of individually cultured bovine embryos. Slaughterhouse-derived bovine oocytes were matured and fertilized in vitro. The presumptive zygotes were cultured individually or cultured in groups of 2 to 5 embryos with a constant culture density (5 mul/embryo). After 7 days of culture, the rates of embryos developed to the blastocyst stage were significantly higher (P < 0.05) in group cultures of more than 3 embryos/drop than for embryo culture of 1 or 2 embryos/drop. These results suggest a beneficial effect of group culture may be exerted by possible growth promoting factors secreted by embryos. In the next experiment, we investigated the effect of timing of fresh medium replacement on the development of embryos cultured in groups. The blastocyst formation rate was lower when culture medium was replaced freshly on days 2-4 after fertilization than on days 5-6. The blastocyst formation rates of single-cultured embryos were significantly (p < 0.05) increased by the addition of conditioned medium derived from multiple-embryo culture. These results indicate that group culture promotes embryo development and that embryo culture-derived conditioned medium is effective for supporting development of single cultured embryos.  相似文献   
72.
Medullary sponge kidney was diagnosed in a 10-year-old male Shih Tzu dog with a long history of hyposthenuria, but with no other findings indicating renal failure or hormonal aberration. At the dog's death from heart failure, an autopsy was performed. On gross morphology, bilateral kidneys were normal size and had many cysts ranging from the corticomedullary junction to renal papillae. Histopathologic findings showed that almost all of the cysts were lined by monolayered or multilayered and columnar or cuboidal epithelium with chilium similar to epididymis. Immunohistochemically, all of these cells were strongly positive for AE1/AE3 and negative for vimentin. Many of these cells were positive for cytokeratin 7 (CK7), and only a few cells were positive for desmin. The results of staining are the same as those for epithelium of the collecting duct of normal canine kidney. This is the first report of this pathologic entity in the canine kidney.  相似文献   
73.
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   
74.
Capsinoids are a group of nonpungent capsaicinoid analogues produced in Capsicum fruits. They have similar bioactivities to capsaicinoids such as suppression of fat accumulation and antioxidant activity. They are more palatable ingredients in dietary supplements than capsaicinoids because of their low pungency. Previous studies on nonpungent Capsicum annuum cultivars showed that capsinoid biosynthesis is caused by loss-of-function putative aminotransferase (p-amt) alleles. This study showed that three mildly pungent cultivars of Capsicum chinense (Zavory Hot, Aji Dulce strain 2, and Belize Sweet) contain high levels of capsinoid. It was shown that these cultivars have novel p-amt alleles, which contain mutations that differ from those of C. annuum. Sequence analysis of p-amt in Belize Sweet revealed that a 5 bp insertion (TGGGC) results in a frameshift mutation. A transposable element (Tcc) was found in the p-amt of Zavory Hot and Aji Dulce strain 2. Tcc has features similar to those of the hAT transposon family. This was inserted in the fifth intron of Zavory Hot and in third intron of Aji Dulce strain 2. The p-amt alleles harboring Tcc cannot produce an active p-AMT. These mildly pungent cultivars will provide a new natural source of capsinoids.  相似文献   
75.
管道进口空气吸入的临界水深试验研究   总被引:1,自引:0,他引:1  
制作1∶3比尺的大小水槽模型,试验研究了灌溉管道进口空气吸入的形式及临界水深与管道流速的关系,得出空气吸入的形式及临界水深与水槽内水流的紊动状态有关,且临界水深随流速的增加而增加的结论。相似性分析表明,临界水深在流速较小时大致符合0.2次方准则,而当流速较大时接近流速一致准则。此外,还根据试验结果对日本有关最小水深标准值进行了讨论  相似文献   
76.
SUMMARY: Adenocarcinomatous growths comprising glandular cavities surrounded by cuboidal to low columnar cells and a large amount of mucus produced by the mucous cells, were observed in the the gastric lymph nodes of a harbor seal Phoca largha. The seal was stranded on the coast of Toyama Bay, Sea of Japan, on 2 March, 1998. Necroscopic examination also showed the animal had significant signet ring cell carcinoma in the stomach, as has been reported elsewhere. The adenocarcinoma may have developed from metastatic cells arising in the gastric carcinoma.  相似文献   
77.
Oxaliplatin (OXL) therapy often causes side effects including chronic peripheral neuropathy. We investigated the pain-relieving effects of recombinant human lactoferrin (rhLf) as well as a long-acting IgG-Fc fused rhLf (rhLf-Fc) on OXL-induced neuropathic pain. We used the hLf in this study, because the homology between mouse Lf and hLf is higher than that of bovine Lf. In addition, rhLf-Fc is expected to enhance the analgesic effect due to the life extension effect in the body. We administered OXL (2 mg/kg, i.v.) to mice twice weekly for 4 weeks. Phosphate buffered saline (PBS), rhLf (100 mg/kg, i.p.) or rhLf-Fc (100 mg/kg, i.p.) was administered once a week from day 15 to 32. We also assessed the continuous infusion of same drugs (10 mg/kg/day) into the external jugular vein by using an osmotic pump. Both of rhLf and rhLf-Fc significantly reduced the hypersensitivity to mechanical stimulation when they were administered intraperitoneally. The continuous infusion of rhLf resulted in a more pronounced effect. Histopathological analysis of sciatic nerve showed that both rhLf and rhLf-Fc tended to reduce nerve fiber damage, but no significant difference was observed in nerve fiber cross-sectional area. Therefore, it was suggested that rhLf or rhLf-Fc injection could be an option for controlling neuropathic pain, which are side effects of OXL.  相似文献   
78.
Decreased cardiac contractility is a central feature of systolic heart failure. Existing drugs increase cardiac contractility indirectly through signaling cascades but are limited by their mechanism-related adverse effects. To avoid these limitations, we previously developed omecamtiv mecarbil, a small-molecule, direct activator of cardiac myosin. Here, we show that it binds to the myosin catalytic domain and operates by an allosteric mechanism to increase the transition rate of myosin into the strongly actin-bound force-generating state. Paradoxically, it inhibits adenosine 5'-triphosphate turnover in the absence of actin, which suggests that it stabilizes an actin-bound conformation of myosin. In animal models, omecamtiv mecarbil increases cardiac function by increasing the duration of ejection without changing the rates of contraction. Cardiac myosin activation may provide a new therapeutic approach for systolic heart failure.  相似文献   
79.
Psittacid herpesvirus type 1 (PsHV-1) was isolated from a captive galah (Eolophus roseicapillus) in Japan that was suspected of having Pacheco's disease (PD), an acute fatal disease in psittacine birds. PsHV-1 has been classified into four genotypes based on the UL16 gene sequence. In the present study, we investigated the genetic and pathogenic characteristics of the isolated virus, FOY-1, compared with a reference strain, RSL-1. The FOY-1 strain was classified into PsHV-1 genotype 2. The FOY-1 strain was found to be less pathogenic to budgerigars than RSL-1, which was classified as genotype 4 in an in vivo study. This is the first report regarding the classification of originally isolated PsHV-1 in Japan and its characterization by animal infection experiment.  相似文献   
80.
Asparagus (Asparagus officinalis L.) is a dioecious plant. In general, male and female plants are used for open-field culture and intensive cultivation, respectively. Farmers distinguish between the sexes by observing the form of the flower organs. However, because flowering begins 2?C3 years after planting, the sexes cannot be differentiated at transplantation by using this method, and planting of an all-male population is not possible. In this study, the usefulness of loop-mediated isothermal amplification (LAMP), a simple method of gene amplification, for sex distinction at the DNA level was determined. In addition, the phenotypic differences in seeds and seedlings of male and female plants were investigated for application as a method of early sex distinction. By using the LAMP method, the sex could be correctly identified in 100% of the seedlings, suggesting that this method is effective for sex distinction at the gene level. Principal component analysis was conducted with 11 selected parameters after investigating the seeds and seedlings of both male and female plants. The results revealed that male plants tend to have many stalks or cladophylls and female plants tend to have large plant forms, suggesting that the sexes can be distinguished by the external appearance of the seedlings before planting. LAMP and observation of the seedling phenotypes could be useful methods of sex distinction for increasing the efficiency of asparagus breeding.  相似文献   
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