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71.
Heartwood extracts from Amazonian trees cumaru-ferro (Dipteryx odorata), jatoba (Hymenaea courbaril), and guarita (Astronium lecointei) exhibit antioxidant activities comparable with that of α-tocopherol, a well-known antioxidant. This article reports the characterization of the antioxidant compounds in the extracts of the three heartwoods. Silica gel column chromatography of the cumaru-ferro EtOAc extract yielded (−)-(3R)-7,2′,3′-trihydroxy-4′-methoxyisoflavan and (+)-(3R)-8,2′,3′-trihydroxy-7,4′-dimethoxyisoflavan. Silica gel column chromatography followed by preparative high-performance liquid chromatography of the jatoba EtOAc extract yielded (−)-fisetinidol and (+)-trans-taxifolin. Chemical structures were assigned using electron-ionization mass spectrometry, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy including nuclear Overhauser effect spectroscopy (NOESY), as well as optical rotation and circular dichroism. Gas chromatography-mass spectrometry demonstrated that the isolated compounds were predominant in the EtOAc extracts. In the guarita EtOAc extract, catechin and gallic acid were identified by comparing their retention times and mass fragmentation patterns with those of authentic samples. Antioxidant activity determined by the 1,1-diphenyl-2-picrylhydrazyl assay demonstrated that all these compounds had activities comparable with that of α-tocopherol. Part of this report was presented at the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, August 2007  相似文献   
72.
A dog presented with hematuria, and two small polypoid masses were detected in the urinary bladder. Histopathologically, the masses were located in the mucosal or submucosal layer. That tissue consisted of a random proliferation of spindle-shaped, round and pleomorphic cells with single or multiple large atypical nuclei and abundant cytoplasm, and eosinophil infiltration. These large cells were confirmed by immunohistochemical staining as fibroblasts, myofibroblasts and macrophages. Mitotic figure was rarely seen. These masses were diagnosed as eosinophilic polypoid cystitis with pseudosarcomatous proliferative tissue, since they consisted of a wide variety of cells and showed low growth activity.  相似文献   
73.
Data from 18 β‐carotene‐deficient Japanese Black cows were collected to clarify the effects of feeding β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin (Ig) in cows. Cows were assigned to control or carrot groups from 3 weeks before the expected calving date to parturition, and supplemental β‐carotene from dry carrots was 138 mg/day in the carrot group. Plasma β‐carotene concentrations in the control and carrot groups at parturition were 95 and 120 μg/dL, and feeding dry carrots slightly improved plasma β‐carotene at parturition. Feeding dry carrots increased colostral IgA concentrations in cows and tended to increase colostral IgG1, but colostral IgM, IgG2, β‐carotene and vitamin A were not affected by the treatment. Feeding dry carrots had no effects on plasma IgG1, IgA and IgM concentrations in cows, but plasma IgG1 concentrations decreased rapidly from 3 weeks before the expected calving date to parturition. These results indicate that feeding β‐carotene‐enriched dry carrots is effective to enhance colostral IgA and IgG1 concentrations in β‐carotene‐deficient cows.  相似文献   
74.
The relationship between hypertension and diabetic peripheral neuropathy (DPN) has recently been reported in clinical research, but it remains unclear whether hypertension is a risk factor for DPN. To investigate the effects of hypertension on DPN, we analyzed morphological features of peripheral nerves in diabetic rats with hypertension. Male WBN/Kob rats were divided into 2 groups: alloxan-induced diabetic rats with deoxycorticosterone acetate-salt (DOCA-salt) treatment (ADN group) and nondiabetic rats with DOCA-salt treatment (DN group). Sciatic, tibial (motor) and sural (sensory) nerves were subjected to qualitative and quantitative histomorphological analysis. Systolic blood pressure in the two groups exhibited a higher value (>140 mmHg), but there was no significant difference between the two groups. Endoneurial blood vessels in both groups presented endothelial hypertrophy and narrowing of the vascular lumen. Electron microscopically, duplication of basal lamina surrounding the endothelium and pericyte of the endoneurial vessels was observed, and this lesion appeared to be more frequent and severe in the ADN group than the DN group. Many nerve fibers of the ADN and DN groups showed an almost normal appearance, whereas morphometrical analysis of the tibial nerve showed a significant shift to smaller fiber and myelin sizes in the ADN group compared with DN group. In sural nerve, the fiber and axon-size significantly shifted to a smaller size in ADN group compared with the DN group. These results suggest that combined diabetes and hypertension could induce mild peripheral nerve lesions with vascular changes.  相似文献   
75.
Objective Fatty liver Shionogi (FLS) mice exhibit characteristic retinochoroidal coloboma because of a failure in fusion of the embryonic optic fissure. However, the same pathogenesis should result in iridal coloboma that has not been reported in this strain. The purpose of this study was to describe the physiologic and morphometric changes in iridal tissue involved in ocular coloboma in FLS mice. Procedures The miotic response after light exposure was evaluated in three strains of live mice, and the shape and location of the pupil were judged macroscopically. Subsequently, macroscopic abnormalities in the anterior segment and fundus were observed postmortem in all mice. During miotic and mydriatic responses in the eyes of live male FLS mice with dyscoric and normal pupils, each iris was measured in four radial directions. The enucleated eyes were examined morphometrically and histologically in both sexes of FLS mice. Results Inferior corectopia upon light‐induced miosis was clearly detected in live FLS mice. The deviated pupils were not round but oval‐shaped. Clinical and postmortem examination revealed that all dyscoric eyes had hypoplastic and dysfunctional irides inferiorly in FLS mice. Histopathological examination confirmed that both the dilator and sphincter muscles and iris stroma were quantitatively diminished in the affected inferior iris. Meanwhile, the rate of fundus (retinochoroidal) coloboma in eyes exhibiting dyscoria was remarkably high, although some dyscoric eyes had no fundus coloboma. Conclusions Fatty liver Shionogi mice had iridal coloboma, resulting in inferior corectopia upon light‐induced miosis as an indicator of ocular coloboma.  相似文献   
76.

Abstracts from the Journal of Japanese Forestry Society

The original papers appeared in the Journal of Japanese Forestry Society vol. 86, no. 3 in Japanese with English abstracts  相似文献   
77.
It is important to conserve forest-dependent organisms not only in broadleaved forests but also in plantation forests. We examined how surrounding forest areas affect forest bird assemblages inhabiting conifer plantations and broadleaved forests in a rural landscape in central Japan. Surrounding forest areas were measured separately as plantation area and broadleaved forest area within 200 m of each sampling site. We used hierarchical partitioning to analyze the effects of surrounding forest areas and stand structures (stand height and understory coverage) on the occurrence of four species groups. We especially focused on mature forest users that are most sensitive to loss of broadleaved forests. Occurrence of mature forest users inhabiting plantation sites was positively affected both by plantation area and broadleaved forest area whereas the occurrence of mature forest users inhabiting broadleaved forests was affected by stand height only. These results suggest that surrounding forest areas were more important to mature forest users in plantations than in broadleaved forests. To conserve mature forest users, increasing surrounding forest areas are important in plantations whereas increasing stand heights would be effective in broadleaved forests.  相似文献   
78.
To investigate the late effects of neutrons at the energy below 1 MeV on the liver carcinogenesis as a function of age, one-week old mice were exposed to 1.0 Gy monoenergetic neutrons (0.317, 0.525 and 1.026 MeV) or 137Cs gamma rays. Survival and carcinogenesis were examined by 18 months of age. Following radiation, tumor incidences in liver, Harderian gland, lung, ovary and pituitary gland were compared. The proportion of the lifespan with liver tumors exposed to neutrons to that exposed to gamma rays was calculated as a function of age. Survival rates among the three groups exposed to neutrons of different energies were not significantly different from one another but shorter than those treated with gamma rays for both sexes. With regard to liver tumor incidence evaluated at 18 months of age, the effectiveness of neutrons to gamma rays was 2.54 for females, and 2.08 for males by the factor. Levels of estrogen in the serum were similar between mice bearing liver tumors and those devoid of tumors. In conclusion, all three energies of neutrons induced similar effectiveness with respect to liver carcinogenicity. Proportions of the lifespan with liver tumors of neutron-exposed to gamma-exposed were shorter in females than males along with ages over 12 months. To obtain this factor at every age contributed for the evaluation of the biological effectiveness of radiations with the parameter of tumor incidence and latency simultaneously.  相似文献   
79.
A 9-year-old, castrated male Japanese domestic cat presented with a complaint of exertional dyspnea. Based on the radiographic findings, presumptive diagnosis of aspiration pneumonia or primary diffuse pulmonary neoplasia in the right middle lobe was made. Histologically, the pulmonary lesion was characterized by diffuse thickening of alveolar wall with the proliferation of apparently atypical irregular-shaped cells. Immunohistochemical staining using anti-human factor VIII-related antigen antiserum showed positive reaction in the cytoplasm of the atypical cells. According to the findings, the lesion was diagnosed as pulmonary intravascular hemangiosarcoma.  相似文献   
80.
To develop ELISA to detect antibodies specific to Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis), the carboxyl termini of the 34 kDa proteins of M. paratuberculosis and Mycobacterium avium subsp. avium (M. avium) were expressed in Escherichia coli expression system. Antibodies specific to M. paratuberculosis were detected with the truncated 34 kDa protein of M. paratuberculosis in ELISA after pre-absorption of serum samples with the truncated 34 kDa protein of M. avium. All the serum samples from cattle confirmed to be infected with M. paratuberculosis were positive and those from healthy cattle were negative in the present ELISA system. These results indicate that the established ELISA detects antibodies specific to M. paratuberculosis with high specificity and sensitivity and is an useful tool for the screening of Johne's disease.  相似文献   
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