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51.
Tada Y Yano N Takahashi H Yuzawa K Ando H Kubo Y Nagasawa A Chin K Kawamata Y Sakai R Ohashi N Ogata A Nakae D 《Journal of toxicologic pathology》2010,23(1):39-47
A subchronic feeding study of l-serine (l-Ser) was conducted with groups of 10 male and 10 female Fischer 344 rats fed a powder diet containing 0, 0.06, 0.5, 1.5 or 5.0% concentrations of l-Ser for 90 days. There were no toxicologically significant, treatment-related changes with regards to body weight, food intake, water intake or urinalysis data. In several of the hematology, serum biochemistry and organ weight parameters, significant changes were observed between some of the treated groups and the controls. All these changes, however, were subtle and lacked any corresponding pathological findings. In addition, the increased or decreased values remained within the range of the historical control values. In fact, histopathological assessment revealed only sporadic and/or spontaneous lesions. In conclusion, the no-observed-adverse-effect-level (NOAEL) for l-Ser was, therefore, determined to be at least a dietary dose of 5.0% (2765.0 mg/kg body weight/day for males and 2905.1 mg/kg body weight/day for females) under the present experimental conditions. 相似文献
52.
Osawa T Miura M Yamagishi N Kim D Fukuda N Fukuoka H Sasaki J Goryo M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(9):1253-1255
A six-month-old Japanese Black bull was found to have no left testis in the scrotum. A fist-sized mass was palpated per rectum. Two months later, hCG was injected and blood samples were collected before and after injection. No testosterone response to hCG was observed. On the cut surface of the excised mass, most of the mass was composed of homogeneous adipose-like tissue. The rest of the surface was composed of a well-circumscribed testicular parenchyma-like tissue (18 × 16 × 15 mm). Histology revealed diffusely distributed mature adipocytes and septa of fibrous connective tissue. Neither germ cells nor spermatozoa were observed in the seminiferous tubules. A diagnosis was made of fibrolipoma and aspermatogenesis of the left cryptorchid testis. 相似文献
53.
Devkota B Takahashi K Matsuzaki S Matsui M Miyamoto A Yamagishi N Osawa T Hashizume T Izaike Y Miyake Y 《The Journal of reproduction and development》2011,57(3):373-378
The present study investigated the basal levels and GnRH-induced responses of peripheral testosterone and estrogen in Holstein bulls with poor semen quality. On the basis of semen parameters, bulls (n=5) having poor semen quality were selected as experimental bulls, and good semen quality bulls (n=4) were used as control bulls. Both groups were treated intramuscularly once with GnRH (250 μg of fertirelin acetate). Blood samples were collected at -1 day (d), -30 min and 0 h (treatment) followed by every 30 min for 5 h and 1, 3 and 5 d post-GnRH treatment (PGT), and LH, testosterone and estradiol-17β (E(2)) concentrations were measured. The pretreatment concentrations were used as basal levels. The percentage increments based on the 0-h levels were calculated per bull for each sampling time until 5 h PGT, and differences were compared between the experimental and control groups. The PGT concentrations of testosterone and basal and PGT concentrations of E(2) were significantly lower in the experimental group. The testosterone increment in the experimental group was delayed and significantly lower from 1 to 5 h PGT than those in the control group. It can be suggested that bulls with poor semen quality have delayed and lower GnRH-induced testosterone response and may also have lower estrogen levels. 相似文献
54.
Michihiko Yatazawa Katsuhisa Furuhashi Norio Kurihara Yoshihisa Ohnishi 《Soil Science and Plant Nutrition》2013,59(3):85-88
There have been several papers dealing with the difference in chemical composition between callus tissue and normal parent tissue. WEINSTEIN, TULECKE, NICKELL, and LAURENCOT (1–3) revealed, in a series of papers, that the contents of amino acids, sugars, and nucleic acids often differed strikingly between callus and normal tissue of Agave toumeyana Trel. (1), Ginkgo biloba, L. (2), and PAUL's scarlet rose (3). STEWARD, THOMPSON, and POLLARD (4) also reported that the content of some amino acids of rapidly growing and randomly proliferating tissue is outstandingly different from that of normal tissue. 相似文献
55.
Botrytis aclada and Botrytis allii, associated with onion gray-mold neck rot and isolated in Hokkaido, were tested for sensitivity to benzimidazole. Of the B. aclada strains, 59% were highly resistant and the remaining 41% were sensitive; all strains of B. allii were sensitive. Resistant strains were widespread in Hokkaido. We analyzed the sequences of the β-tubulin gene of resistant strains and detected the replacement of glutamic acid (GAG) by lysine (AAG) at codon 198. This is the first report of benzimidazole resistance in B. aclada. This study revealed a difference in fungicide sensitivity between the two Botrytis species.
相似文献56.
In water-efficient rice production, grain yield is often constrained by panicle size. The objective of this study was to genetically dissect the response of panicle morphology to irrigation regimes in aerobic rice culture. We grew ‘Akihikari’ (a lowland japonica cultivar) × ‘IRAT109’ (an upland japonica cultivar) backcross inbred lines in aerobic soils with full or limited irrigation for 2 years, and examined 4 panicle traits—number of florets per panicle (FPP), number of primary branches per panicle (BPP), number of florets per primary branch (FPB), and frequency of pre-flowering floret abortion (%FA)—and grain yield. QTLs for BPP were detected in both the irrigation regimes but QTLs for FPB and %FA were detected mostly only in either of the irrigation regimes. The QTL for FPP on chromosome 2 (RM3421–RM213) coincided with that for yield under full irrigation, showing that this QTL is related to sink capacity and yield potential in aerobic rice culture. On the other hand, the QTL for FPB on chromosome 1 (RM3148–RM243) coincided with that for yield under limited irrigation, when water deficit was moderate. The QTL for root axis length at vegetative stage, previously identified in the same mapping population, was located near this region. This study unravelled the complicated genetic control on panicle morphology in aerobic rice culture, and suggested the positive roles of the dehydration avoidance mechanism by vigorous root growth on panicle size and yield under dry soil conditions. 相似文献
57.
The analysis of saltwater intrusion through Komesu underground dam and water quality management for salinity 总被引:2,自引:1,他引:1
The Komesu underground dam is the first full-scale underground dam constructed to prevent saltwater intrusion in Japan. Although
the cutoff wall of the dam effectively reduces the movement of saltwater into the reservoir area, saltwater masses remained
behind the dam at the time of its completion, and saltwater can intrude beneath and diffuse through the wall, particularly
when the reservoir level is below the sea level because of high pumping levels during the drought years. Therefore, it is
necessary to estimate in advance whether the saltwater concentration in the pumped water is likely to exceed or not the permissible
salinity level because of an increase in the residual saltwater mass as a result of saltwater intrusion and to take necessary
measures to suitably manage the saltwater level behind the dam. To analyze saltwater intrusion, we first selected the optimal
program suitable for the analysis of saltwater intrusion. Second, we examined the longitudinal dispersivity and the effect
of the cone of depression around the pumping wells. Then we analyzed saltwater intrusion into the reservoir area in detail
by using a two-dimensional convective–dispersive analysis. The results of the analysis make it possible to improve management
of saltwater in the reservoir area behind the underground dam. 相似文献
58.
Matsuda Y Ikeda H Moriura N Tanaka N Shimizu K Oichi W Nonomura T Kakutani K Kusakari S Higashi K Toyoda H 《Phytopathology》2006,96(9):967-974
ABSTRACT In an attempt to physically protect greenhouse tomato plants from the powdery mildew fungus Oidium neolycopersici, we developed a new electrostatic spore precipitator in which a copper wire conductor is linked to an electrostatic generator and covered with a transparent acrylic cylinder (insulator). The conductor was negatively charged by the generator, and the electrostatic field created by the conductor was used to dielectrically polarize the insulator cylinder. The dielectrically polarized cylinder also produced an electrostatic force without a spark discharge. This force was directly proportional to the potential applied to the conductor and was used to attract conidia of the pathogen. The efficacy of this spore precipitator in protecting hydroponically cultured tomato plants from powdery mildew was evaluated in the greenhouse. The hydroponic culture troughs were covered with a cubic frame installed with the spore precipitator, and the disease progress on precipitator-guarded and unguarded seedlings was traced after the conidia were disseminated mechanically from inoculum on tomato plants. Seedlings in the guarded troughs remained uninfected during the entire experiment, in spite of rapid spread of the disease to all leaves of the unguarded seedlings. 相似文献
59.
Norio Yamagishi DVM PhD Kazutaka Yamada DVM PhD Hiroshi Ishikawa DVM PhD Haruo Yamada DVM PhD 《Veterinary radiology & ultrasound》2000,41(5):422-424
A dog with a bronchocutaneous fistula is described. Contrast enhanced computed tomography was useful for diagnosis and treatment of the fistula in this dog. 相似文献
60.
以棉花为碳源去除地下水硝酸盐的研究 总被引:35,自引:0,他引:35
采用室内试验装置,研究了以棉花为碳源和反应介质的生物反应器去除地下水中的硝酸盐。结果表明,以棉花为碳源的反应器启动快。在室温25℃±1℃,进水硝酸盐氮浓度为22.6mgN·L-1,水力停留时间不小于9.8h时,反应器对硝酸盐氮可以100%去除,出水未检出亚硝酸盐。反硝化反应受温度变化及水力停留时间影响大:14℃的反硝化速率不到25℃的1/2;当水力停留时间为7.2h,N去除效率只有45%。反硝化反应受pH值和DO的影响小,当pH值在6~9,进水DO在2~6mg·L-1范围变化时,反应器去除效率没有变化。在反应进行过程中,棉花也被消耗掉。 相似文献