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81.
Makoto Watanabe Naoki Matsuo Masahiro Yamaguchi Hideyuki Matsumura Yoshihisa Kohno Takeshi Izuta 《European Journal of Forest Research》2010,129(3):421-430
A risk assessment of ozone (O3) impact on the annual carbon absorption (ACA) of Japanese representative conifers was conducted based on the results of an experimental study, monitoring data of oxidant
concentrations and vegetation surveys. The areas with high O3-induced reduction in ACA did not necessarily correspond to the areas with relatively high O3-exposure. Widespread distribution of O3-sensitive tree species such as Pinus densiflora and Larix kaempferi, and high ACA were important factors that induced a high risk of O3 impact on the ACA. Therefore, we concluded that not only the accumulated O3-exposure but also the variety of tree habitat, the tree sensitivity to O3 and the ACA among the tree species must be taken into account to assess the risk of O3 impact on the ACA of Japanese conifers. The O3-induced reduction in the total ACA of the three tree species in Japan was estimated to be 0.8%. 相似文献
82.
Taizo Nakamori Satoshi Yoshida Yoshihisa Kubota Tadaaki Ban-nai Nobuhiro Kaneko Makiko Hasegawa Ryosaku Itoh 《European Journal of Soil Biology》2008,44(3):266-270
Knowing whether test species used for single-species toxicity tests are representative of other species provides valuable information because contaminant effects are often extrapolated to the community level based on these tests. To evaluate how representative the sensitivity of the standard test collembolan species Folsomia candida is for Collembola, we devised toxicity tests using the collembolan species Onychiurus yodai and Sinella umesaoi, which exhibit life-forms different from F. candida. Sensitivity to cadmium (Cd) was compared between F. candida and the novel test species. The 50% effective concentrations for reproduction were 154.7, 72.2 and 40.9 mg Cd/kg dry soil for O. yodai, F. candida and S. umesaoi, respectively. Thus, the reproductive sensitivity of F. candida to Cd was between that of the other two species. Increasing reproductive sensitivity to Cd corresponded to increasing activity levels and a more surface-dwelling life-form. Our data may facilitate the generalisation of effect data for F. candida to other species. 相似文献
83.
A piglet with concurrent polioencephalomyelitis due to porcine teschovirus and postweaning multisystemic wasting syndrome 总被引:4,自引:0,他引:4
Takahashi M Seimiya YM Seki Y Yamada M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(5):497-500
A piglet developed respiratory distress followed by difficulty in standing and unsteady gait. The lesions were characterized by polioencephalomyelitis with the predominant distribution in the brain stem, as well as lymphocyte depletion and histiocyte infiltration with cytoplasmic inclusion bodies in the lymphoid tissues throughout the body and interstitial pneumonia. Porcine teschovirus (PTV) antigens were found in the former lesions and porcine circovirus 2 (PCV2) in the latter two lesions. PTV genes were detected from the diencephalon. The results suggest that the piglet was concurrently affected with polioencephalomyelitis due to PTV and postweaning multisystemic wasting syndrome (PMWS) associated with PCV2. They also suggest that the immunosuppressive condition developing in PMWS may have facilitated the infection of the brain with PTV. 相似文献
84.
Masafumi Amano Katsumi Aida Naoto Okumoto Yoshihisa Hasegawa 《Fish physiology and biochemistry》1993,11(1-6):233-240
Levels of two types of gonadotropin-releasing hormone (salmon GnRH and chicken GnRH-II) in the brain and pituitary, and content of gonadotropin (GTHIβ and IIβ) in the pituitary were measured in male masu salmon from hatching to gonadal maturation for three years in order to clarify the involvement of GnRHs in precocious maturation. Underyearling precocious males were distinguishable in summer of year 1 and were marked by an increased GSI. Spermiation was observed among these individuals thereafter every autumn. Pituitary GTHIβ content in both precocious and immature males, and GTHIIβ content in precocious males showed seasonal fluctuations — high in autumn and low in winter. Pituitary GTHIIβ content was low in immature males. Pituitary sGnRH content in precocious males increased from spring to autumn during the three-year period. sGnRH concentrations in discrete brain areas showed seasonal changes — high during autumn to winter and low in summer. Concentrations in the olfactory bulbs and hypothalamus increased significantly in association with testicular maturation during year 3. sGnRH concentrations in the hypothalamus were significantly higher in precocious males than in immature males; this was possibly due to positive feedback of steroid hormones. cGnRH-II was undetectable in the pituitary and no distinct changes were observed in its concentration in the brain in relation to maturation. The phenomenon of underyearling precocious maturation is considered to be triggered before the onset of early summer. It is suggested that males which mature precociously are larger in size and contain much sGnRH in the pituitary before the outward signs of precocity appear; sGnRH may stimulate GTH II synthesis and induce precocious maturation. 相似文献
85.
豌豆根系分泌物自毒作用的研究 总被引:69,自引:4,他引:69
向营养液中添加活性炭显著促进了豌豆植物株的生长,而未添加活性炭的栽培残液提取物则对豌豆和莴苣胚根伸长均表现出明显的抑制作用。生长抑制物质主要在花前分泌,分泌物中酸性,中性和碱性物质均具有较强的生长抑制活性。用气相色谱/质谱联用仪从根系分泌筘鉴定出苯甲酸,对羟基本甲酸,香草酸,肉桂酸,香豆酸,3,4-二羟在苯甲酸,3-5二甲羟基香豆酸等7个生长抑制物质。 相似文献
86.
Derar RI Maeda Y Hoque SM Osawa T Watanabe G Taya K Miyake Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(1):31-35
Two pony mares were immunized against recombinant porcine inhibin alpha subunit three times with 39 day intervals. Clinical findings and endocrinological changes before immunization were taken as the control. The first significant rise in the anti-inhibin titre (P<0.05) in the circulation was found 27 days after the first injection. Maximum binding activity was reached by the 12th day after the second booster dose. The number of small, medium and large sized follicles had increased significantly compared to before immunization (11.75 +/- 4.30, 2.75 +/- 0.69 and 2.51 +/- 0.63 vs 6.50 +/- 1.43, 1.83 +/- 0.44 and 1.33 +/- 0.38, respectively), but the ovulation rate remained unchanged after immunization. The average plasma concentration of FSH and estradiol-17beta during the estrous cycle increased significantly (P<0.05) after immunization. These results suggest that immunization against inhibin is a useful tool to increase the number of ovarian follicles during the estrous cycle of pony mares. Moreover, the present study supported the concept that inhibin plays a major role in the control of follicular growth through its inhibitory effect on FSH secretion synergistically with steroid hormones. 相似文献
87.
Miyake M Yaguchi T Saze K Wang J Ogawa T Endo Y Suzuta Y Okazaki M Haga Y Waki T Takahashi SY Yamamoto Y Iwabuchi S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(1):9-14
Hepatocyte growth factor (HGF) is a pleiotropic cytokine that stimulates a wide array of cellular targets, including hepatocytes and other epithelial cells, melanocytes, endothelial and hematopoietic cells. We have cloned a different form of cDNA, with a deletion of 15 base pairs predicted to result in the loss of 5 amino acids from the first kringle domain. To investigate the biological activity, original and deleted variant of feline HGF cDNAs were transiently expressed in COS-7 cells. Both recombinant feline HGFs showed almost the same dose-response curves in the stimulation of the growth of BNL CL.2 cells (a mouse hepatocyte cell line) and scatter activity of Madin-Darby canine kidney (MDCK) cells. The findings reported here suggest that the deleted variant of feline HGF has almost the same biological activity as the original in terms of the proliferation and scatter activity. 相似文献
88.
Hirao H Inoue T Hoshi K Kobayashi M Shimamura S Shimizu M Tanaka R Takashima K Mori Y Noishiki Y Yamane Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(4):357-362
A new valved conduit was developed using a canine aortic valve. The bioprosthetic valve was fixed with glutaraldehyde and epoxy compound (Denacol-EX313/810). A vascular graft composed of ultra-fine polyester fiber (10 mm in diameter, 200 mm in length) was used. Four dogs underwent apico-aortic valved conduit (AAVC) implantation and aortic banding (bypass group, BG), while another 4 dogs underwent aortic banding without AAVC implantation (control group, CG). Cardiac catheterization and angiocardiography were performed for assessment of hemodynamics 2 weeks and 6 months after surgery. Left ventricular systolic pressure, left ventricular end-diastolic pressure and the left ventricular-aortic pressure gradient differed significantly (P<0.01) between the BG and CG dogs. Left ventricular angiocardiography showed patency of the valved conduit in all the BG dogs. Echocardiography was performed before and 2, 4 and 6 months after surgery, and showed that while pressure overload caused concentric myocardial hypertrophy in the CG dogs, the left ventricle dilated eccentrically in the BG dogs. Furthermore, relief of left ventricular pressure overload by AAVC was maintained. 相似文献
89.
Percutaneous transcatheter coil embolization of a ventricular septal defect in a dog 总被引:1,自引:0,他引:1
Shimizu M Tanaka R Hirao H Kobayashi M Shimamura S Maruo K Yamane Y 《Journal of the American Veterinary Medical Association》2005,226(1):69-72, 52-3
A 4-month-old male French Bulldog weighing 5.0 kg (11 lb) was referred for a heart murmur. A grade 3/6 systolic murmur was detected at the left heart base and a grade 4/6 systolic murmur was detected at the right heart base. By use of color-flow Doppler ultrasonography and cardiac catheterization, a diagnosis of supracristal ventricular septal defect (VSD) with accompanying aortic regurgitation was made. Percutaneous transcatheter coil embolization was used to close the VSD. Because residual shunt was detected via echocardiography after coil implantation, the residual shunt was followed periodically via echocardiography to detect spontaneous closure of the VSD. Volume overload in the left ventricle was detected in the dog 131 days after admission. Additional coils were placed 137 days after admission. Hemolysis resulting in hemoglobinuria was detected, but this complication was mild. In the dog of this report, results of coil occlusion for correction of VSD were promising. Thus, coil occlusion should be considered as an alternative treatment for VSD in dogs. 相似文献
90.
Ando T Annaka A Ohtsuka H Kohiruimaki M Hayashi T Hasegawa Y Watanabe D 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(1):95-98
To investigate the effect of hoof trimming before the dry period, the hooves of 10 cows (trimmed group) were trimmed at 79.6 +/- 8.6 days before parturition and the hooves of 52 cows were left untrimmed (control group). Blood biochemistry and hormone concentrations were investigated for 6 cows from each group. The daily milk yield after parturition in the trimmed group tended to be higher than that of the control group. Between 0 and 30 days after parturition, the levels of non-esterified fatty acids were significantly lower stet, and the plasma glucose and glucose disposal rates were significantly higher in the trimmed group. The plasma cortisol concentration was stable before and after parturition in the trimmed group. Hoof trimming before the dry period appears to reduce stress and maintain the nutritional conditions of perinatal dairy cows. 相似文献