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31.
Seasonal changes in the spermatogenic epithelium of adult Japanese macaques (Macaca fuscata fuscata)
Tomoo Enomoto Kiyoaki Matsubayashi Yasukazu Nagato Mayumi Nakano 《Primates; journal of primatology》1994,35(4):465-472
A histological study was undertaken to clarify seasonal changes in the spermatogenic epithelium of Japanese macaques. Testicular
tissue samples were excised by biopsies from five adult laboratory-maintained males in mating and non-mating seasons. The
samples were fixed with Bouin's solution, embedded in paraffin, and stained with PAS and hematoxylin. Microscopic observations
on cross-sections of seminiferous tubules revealed that the seminiferous epithelium in the mating season was thicker than
in the non-mating season. PAS-stained granules were found in some of the dark A-type spermatogonia, which significantly increased
in the non-mating season. Spermatids of the steps preceding the appearance of the acrosomic cap in stages I to III were observed
significantly more often than those in the step coinciding with the formation of the acrosomic cap in stage IV. In stage I,
the ratio of mature spermatids or spermatozoa to immature spermatids in the mating season was higher than that in the non-mating
season. These findings suggest that spermiogenesis, as well as spermatocytogenesis, is inhibited in the non-mating season. 相似文献
32.
The human gene encoding the mutual signal-transducing subunit (-chain) of granulocyte-macrophage colony-stimulating factor, interleukin-3, and interleukin-5 receptor complexes has been mapped to chromosome 22q13.1 by the fluorescence in situ hybridization method. 相似文献
33.
S. Takai M. Kasama K. Yamada N. Kai N. Hirayama H. Namiki T. Taniyama 《Human genetics》1994,93(1):13-15
The human FcRI gene encodes for a highaffinity Fc receptor that plays pivotal roles in the immune response. We have used fluorescence in situ hybridization analysis to localize the FcRI gene to human chromosome 1. The human FcRI (CD64) gene has been assigned to human chromosome 1q21.2-q21.3 using R-banded human (pro)metaphase chromosomes. 相似文献
34.
Hideaki Sato Hideki Hirayama Takeshi Yamamoto Yoshimasa Lchio Fumiaki Ishizawa Michinao Mizugaki 《Luminescence》1994,9(2):73-77
The purpose of the study was to evaluate the quality of Toki-shakuyaku-san extract granules (TJ-23) using chemiluminescence (CL). A linear relationship was obtained between the log value of the CL of TJ-23 and the reaction temperature. An excellent correlation (r= 0.999) was found between the slope of this curve (ΔA) and the colour intensity due to the browning reaction occurring at the early stage of the Maillard reaction. 相似文献
35.
Fecundity patterns of S and L type rotifers Brachionus plicatilis, which were previously found to have distinct growth ability, were analyzed using data of age-specific fecundity. The data were obtained by individual cultures of S and L type strains at 17, 24 and 34 °C. The pattern was analyzed by using normal probability functions. When the age was transformed into logarithmic value, the S and L types had an identical pattern of fecundity at every temperature. This fact indicates that the difference of the growth response to the temperature between S and L type strains stemmed only from the differences in net reproduction rate, not from the pattern. 相似文献
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38.
Mayumi Nishikata Aki Nakai Hitomi Fushida Keishiro Miyake Takaichi Arita Ken Iseki Katsumi Miyazaki Akikazu Nomura 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1993,612(2)
A method is described for the simultaneous determination of (+)- and (−)-homochlorcyclizine (HCZ) in human urine by high-performance liquid chromatography on a chiral stationary phase of ovomucoid-bonded silica. The pH of the buffer and organic modifier in the mobile phase markedly affected the chromatographic separation. A mobile phase of methanol—0.02 M acetate buffer (pH 4.7) (25:75, v/v) at a flow-rate of 1.0 ml/min was used for the urine assays. The ultraviolet absorption was monitored at 240 nm, and diphenhydramine was employed as the internal standard for the quantitation. (+)-HCZ, (−)-HCZ and the internal standard were eluted at retention times of 15, 25 and 8 min, respectively. The limit of determination for HCZ enantiomers was ca. 50 ng/ml of urine. One of the metabolites in human urine, which was a quaternary ammonium-linked glucuronide, could also be determined in a manner similar to unchanged HCZ after β-glucuronidase hydrolysis. A pharmacokinetic study was conducted with three healthy volunteers, who each received a single oral dose of racemic HCZ (20 mg). Distinct differences were found between the two enantiomers, particularly in the metabolic process, that is, the urinary excretion as (−)-HCZ-glucuronide within 48 h was ca. four times higher than that of the (+)-isomer. This method should be very useful for enantioselective pharmacokinetic studies of HCZ. 相似文献
39.
Mayumi Shimizu Kazunari Inaba Toyokazu Yoshida Takayoshi Toda Akio Iwashima Toshio Mitsunaga 《Physiologia plantarum》1995,93(1):93-98
Three thiamine-binding proteins of 17-19 kDa (STBP-I, II, and III) were purified from sesame seed (Sesamum indicum L.). Each of the proteins was composed of two subunits of equal molecular mass and each subunit consisted of a large polypeptide and a small polypeptide linked by a disulfide bond(s). They were rich in glutamic acid (or glutamine) and arginine. Their binding activities were optimal at neutral pH. They bound specifically free thiamine but not thiamine phosphates. STBP-I had higher affinity for thiamine than STBP-II or STBP-III. STBP-II and STBP-III bound one molecule of thiamine per molecule, and STBP-I bound 0.5 molecule. The amino acid composition and structure of the STPBs were similar to those of 2S storage proteins. 相似文献
40.
The concept of biological control methods in aquaculture 总被引:10,自引:0,他引:10
Masachika Maeda Kinya Nogami Masaei Kanematsu Kazutsugu Hirayama 《Hydrobiologia》1997,358(1-3):285-290
Microbial techniques of biocontrol using the interaction ofmicroorganisms to repress the growth of deleterious bacteria andviruses were developed. The bacterial strain used in this work alsoimproved the growth of fishes and crustaceans. Using the conceptandprocedures of the biocontrol method described here, the aquacultureproduction became stable and evenincreased. 相似文献