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101.
Vertebral deformities were investigated in cultured red sea bream, Pagrus major. In the field, deformities in seedlings were categorized and their incidence was calculated. In the laboratory, the symptoms of major vertebral deformities were examined morphologically using radiographs and by making transparent skeletal specimens. The internal structure of deformed vertebrae was examined histologically. The shortened body condition had the highest incidence (0.9–8.3%) of all deformities in the seedlings. In individuals with the shortened body condition, the ratio of trunk and caudal part length to body height was smaller. These fish had skeletal anomalies in the vertebrae, mainly centrum defects (64.3%) or undersized centrums (25.2%). The specimens with centrum defects had a characteristic anomaly in the vertebrae, with plural pairs of neural and haemal spines on a single centrum. This anomaly was frequently observed in the posterior abdominal vertebrae. The internal skeletal structure of such abnormal centrums was basically the same as that of normal centrums. In all the specimens with undersized centrums, both the centrum length and diameter were shorter than normal except for the first and second centrum, and urostyle. 相似文献
102.
The time-course changes in calcium and phosphorus contents, dry weight, and area during scale regeneration in the goldfish,
Carassius auratus L. were quantified. Histological observations were then conducted to understand the mutual relationship between the quantitative
and morphological processes of scale regeneration. The quantitative study revealed that regenerating scales grow most rapidly
in area during the first 5 days of regeneration. The gradual decrease in the area growth rate coupled with the continuous
linear weight growth over the period of 5–28 days suggests a shift in growth priority from area growth to the apposition,
of the basal plate. Calcium and phosphorus deposition proceeded almost linearly during scale regeneration. Calcification of
the bony layer preceded that of the basal plate and, after 14 days of regeneration, calcification of the basal plate started
and gradually progressed. On day 28, recovery of calcium and phosphorus contents in the regenerating scales were approximatley
72% of ontogenetic scales, which is lower than the rates of area and weight regeneration (104 and 85%, respectively). Late
initiation and slow progress of calcification in the basal plate is suggested to be responsible for the slow regeneration
in calcium and phosphorus contents. 相似文献
103.
104.
Endosulfan, an organochlorine insecticide, and its metabolite endosulfan sulfate are persistent in environments and are considered
toxic. We investigate the possible nontoxic bioremediation of endosulfan. An endosulfandegrading fungus that does not produce
endosulfan sulfate was selected from eight species of white-rot fungi. High degradation of endosulfan and low accumulation
of endosulfan sulfate were found in cultures of Trametes hirsuta. A degradation experiment using endosulfan sulfate as the substrate revealed that T. hirsuta is able to further degrade endosulfan sulfate following the oxidative conversion of endosulfan to endosulfan sulfate. Endosulfan
and endosulfan sulfate were converted to several metabolites via hydrolytic pathways. In addition, endosulfan dimethylene,
previously reported as a metabolite of the soil bacterium Arthrobacter sp., was detected in T. hirsuta culture containing endosulfan sulfate. Our results suggest that T. hirsuta has multiple pathways for the degradation of endosulfan and endosulfan sulfate and thus has great potential for use as a
biocatalyst in endosulfan bioremediation. 相似文献
105.
Masaaki Sugiura Yoshihiro Horibe Hitoshi Kawada Masahiro Takagi 《Pest management science》2011,67(9):1115-1123
BACKGROUND: Although insecticidal aerosols have been widely accepted for household use, the discharged amount should be maintained at minimum levels because they contain volatile organic compounds. Hence, it would be valuable to develop a technique whereby insecticide droplets adhere efficiently to an insect's body. The present study was undertaken in order to clarify how differences in the mode of adhesion to the insect body influence the knockdown effect. RESULTS: When the discharged volume of droplets with different diameters was the same, the adhesion volume of larger droplets was twice that of smaller droplets, resulting in a higher insect knockdown. In contrast, when the adhesion volume of the two droplet types was the same, a greater number of smaller droplets than larger droplets adhered, and the smaller droplets caused higher insect knockdown. The knockdown effect of both droplet types was lowered when the mesothoracic spiracles of cockroaches were blocked; however, the effect of larger droplets was lowered to a lesser degree. CONCLUSION: The results suggest that, the probability of adhesion to the more susceptible regions of an insect's body, i.e., areas surrounding the mesothoracic spiracles, was improved when a greater number of smaller droplets were adhered, resulting in higher knockdown. Copyright © 2011 Society of Chemical Industry 相似文献
106.
Takami S Ogawa K Umemura T Hibi D Ishii Y Okamura T Tasaki M Inoue T Suzuki Y Jin M Cho YM Nishikawa A 《Journal of toxicologic pathology》2011,24(1):63-67
Carcinosarcomas are rare tumors in humans as well as rats and most commonly occur in the uterus. Recently, we observed a case of incidental carcinosarcoma of the uterus in a female Wistar Hannover GALAS [BrlHan:WIST@ Jcl (GALAS)] rat at 2 years of age. Histopathologically, the tumor was characterized by an admixture of malignant epithelial and nonepithelial elements. The carcinomatous components represented a type of endometrial carcinoma, consisting of glandular and solid proliferation of large-sized tumor cells. Prominent mitoses and tumor cell invasion were observed. The sarcomatous components were characterized by multifocal proliferation of severe atypical cells with cartilage matrix and were diagnosed as chondrosarcoma. Transitions between carcinomatous and sarcomatous components were observed, and many tumor cells in the solid lesion showed immunohistochemical reactivity with both cytokeratin and vimentin. Based on these findings, this tumor was diagnosed as a uterine carcinosarcoma. This is the first report of uterine carcinosarcoma in Wistar Hannover GALAS [BrlHan:WIST@Jcl (GALAS)] rats. 相似文献
107.
Toshiya HASUNUMA Kenji KAWASHIMA Kiyoshi AKIYAMA Kenji YASUDA Fuminori TERADA Shiro KUSHIBIKI 《Animal Science Journal》2011,82(4):543-548
We investigated the effect of cellooligosaccharide (CE) or a combination of dextran and Lactobacillus casei ssp. casei strain JCM1134T (synbiotic; SB) feeding on growth performance, fecal condition and hormone concentrations in Holstein calves. Fifty‐two female Holstein calves were randomly assigned to three treatment groups: CE feeding group (n = 16), SB feeding group (n = 18), and control group (n = 18). Body weight at 90 days of age, as well as daily body weight gain (DG) and feed efficiency after weaning to 90 days of age were greater (P < 0.05) in the CE feeding group than in the control group. The total fecal score tended to be lower (P < 0.1) in the SB feeding group than in the control group. Plasma insulin concentration was higher (P < 0.05) in the CE feeding group than in the control group at 90 days of age. Our results indicate that CE feeding improved DG and feed efficiency in calves. On the other hand, there was less effect on growth performance and fecal Escherichia coli counts in calves fed SB. 相似文献
108.
K Ono K Inui T Hasegawa N Matsuki H Watanabe S Takagi A Hasegawa I Tomoda 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(4):759-765
The change in activities of 3 major antioxidative enzymes in equine erythrocytes, superoxide dismutase (SOD), glutathione peroxidase (GSHpx), and catalase, was investigated in order to evaluate the effect of exercise. Blood samples were obtained from 11 thoroughbred horses before and immediately after vigorous exercise which induced the increase of plasma lipid peroxide (Lpx) concentration from 1.16 +/- 0.40 nmol/ml to 1.29 +/- 0.34 nmol/ml. Following the exercise, the GSHpx activity in erythrocytes was significantly reduced from 69 +/- 10 IU/gHb to 65 +/- 8 IU/gHb, whereas SOD and catalase activities were not changed. Effects of an antioxidative compound, containing selenium and vitamin E(Se-E), on the response of antioxidative enzyme activities following the exercise were examined. Seven horses were injected intramuscularly with Se-E(Se:25 mg, vitamin E:54.8 mg) and received the same vigorous exercise. After Se-E treatment, plasma Lpx levels before the exercise were decreased from 1.24 +/- 0.09 nmol/ml to 0.86 +/- 0.03 nmol/ml, however, SOD, GSHpx, and catalase activities were not varied. The Se-E treatment slightly prevented the decrease in GSHpx activity and the increase in plasma Lpx level after the exercise, having no effect on SOD and catalase activities. These results suggested that the changes of GSHpx activity in erythrocytes might reflect the protective condition against exercise-induced lipid peroxidation. 相似文献
109.
110.