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81.
The purpose of this study was to evaluate the feasibility, safety, and efficacy of transcatheter closure in dogs with a congenital perimembranous ventricular septal defect (VSD) by using a detachable coil. No dogs showed any symptoms, and results of chest X-rays and ECGs were normal. The diameters of VSD ranged from 2 to 4 mm on echocardiogram. The defect was 2-2.5 mm from the aortic valve. A detachable coil (size 5 mm with 5 loops) designed for patent ductus arteriosus was delivered via the transarterial route. The device was successfully employed in all dogs. A minimal residual shunt was observed in all dogs even though Qp/Qs decreased. Hemolysis and a rate-dependent right-bundle branch block were observed in 1 dog, but there was no clinical significance. No major complication was noted. Pathologic examination after 1 year revealed that the coils were covered with tissue without significant damage to the His-Purkinje conduction system. In conclusion, transcatheter closure of a small perimembranous VSD with a detachable coil can be achieved without major complications or significant pathologic damage at the lesion site.  相似文献   
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G8 bovine group A rotaviruses isolated in Japan were genetically and serologically characterized. The VP7 gene nucleotide and amino acid sequences revealed high identity with each other. All Japanese G8 strains were classified into the same lineage in the phylogenetic analysis based on VP7 gene sequences. Antisera to four Japanese G8 strains neutralized other G8 strains, but their neutralizing titers were between 8-fold lower and 2-fold higher than homologous strains. These results suggest that the VP7s of Japanese G8 strains have similar genetic and serologic characteristics. Observed differences in the neutralizing abilities of antisera for each strain appear to depend on differences in the P serotypes/genotypes.  相似文献   
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Structural and physicochemical characteristics of endosperm starch from milled rice grains of seven Japanese cultivars used in sake production were examined. Amylose content was 15.2–20.2%, number-average degree of polymerization (DPn) of amylose was 900–1,400, and the ratio of short-to-long chain amylopectin was 2.7–3.5, respectively. The degree of retrogradation of purified starch stored for seven days at 4°C after gelatinization was 20–31%. The degree of retrogradation correlated negatively with the ratio of short-to-long chain amylopectin. The effect of holding time after steaming on enzyme digestibility and starch retrogradation of steamed rice grains was investigated. The longer the holding time after steaming, the greater the extent of retrogradation, and the less the degree of enzymatic digestibility. The decreased rate of enzyme digestibility correlated with amylopectin chain length distribution. Samples with short-chain amylopectin exhibited a slow decrease in enzyme digestibility. It was determined that the structure and retrogradation properties of endosperm starch in Japanese rice cultivars affect the decreasing rate of enzyme digestibility of the steamed, milled rice grains.  相似文献   
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Feral raccoons (Procyon lotor) have been growing in number in Japan, and they are becoming a problematic invasive species. Consequently, they are commonly captured and killed in pest control programs. For effective population control of feral raccoons, it is necessary to understand their reproductive physiology and ecology. Although the reproductive traits of female raccoons are well known, those of the males are not well understood because specialized knowledge and facilities are required to study them. In this study, we first used a simple evaluation method to assess spermatogenesis and presence of spermatozoa in the tail of the epididymis of feral male raccoons by histologically examining the testis and epididymis. We then evaluated the possibility of using 7 variables—body weight, body length, body mass index, testicular weight, epididymal weight, testicular size and gonadosomatic index (GSI)—to estimate spermatogenesis and presence of spermatozoa in the tail of the epididymis. GSI and body weight were chosen as criteria for spermatogenesis, and GSI was chosen as the criterion for presence of spermatozoa in the tail of the epididymis. Because GSI is calculated from body weight and testicular weight, this model should be able to be used to estimate the reproductive state of male raccoons regardless of season and age when just these two parameters are known. In this study, GSI was demonstrated to be an index of reproductive state in male raccoons. To our knowledge, this is the first report of such a use for GSI in a member of the Carnivora.  相似文献   
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Insulin secretion from intact mouse pancreatic islets was investigated with two-photon excitation imaging. Insulin granule exocytosis occurred mainly toward the interstitial space, away from blood vessels. The fusion pore was unusually stable with a lifetime of 1.8 seconds. Opening of the 1.4-nanometer-diameter pore was preceded by unrestricted lateral diffusion of lipids along the inner wall of the pore, supporting the idea that this structure is composed of membrane lipids. When the pore dilated to 12 nanometers, the granules rapidly flattened and discharged their contents. Thus, our methodology reveals fusion pore dynamics in intact tissues at nanometer resolution.  相似文献   
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