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31.
Morphological variation of the skull was examined in the northern treeshrew (Tupaia belangeri) from various localities across Southeast Asia. Through a multivariate analysis, the treeshrews from South Vietnam exhibited distinct morphological characteristics compared to other populations from Thailand and Laos, and Malaysia. The plots of the specimens of North Vietnam are not randomly mixed with Thailand plots segregation in the scatteregrams of canonical discriminant analysis. Since the skulls of the population from North Vietnam were morphologically similar to those form central Laos and northern and northeastern Thailand, the zoogeographical barrier effect of Mekong River was not clearly confirmed. The population of the Kanchanaburi in western Thailand is clearly smaller in size compared to the other populations. The southern border of the distribution of this species is determined by the Isthmus of Kra or Kangar-Pattani Line. In the northern treeshrew, which is distributed from southern China to Bangladesh and southern Thailand, we have detected osteometrical geographical variation driven by geography. These results indicate that the skull morphology in the Tupaia glis-belangeri complex distinctively differs in South Vietnam, western Thailand, and southern Thailand. The zoogeographical barrier and factor separating these districts are expected to clarify in the future.  相似文献   
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A dog with purulent vulval discharge was found to have many cysts containing purulent mucus in the uterine cervix. The uterine horns did not contain any pus. Histological examination revealed a cervical adenomyosis infiltrated by many neutrophils. After an ovariohysterectomy including the whole cervix, the dog recovered well.  相似文献   
33.
Bovine interferon (bIFN) tau, which plays a key role in maternal-fetal recognition of pregnancy, was expressed by an Autographa californica nuclear polyhedrosis virus expression system. cDNA coding bIFNtau was derived from cultured trophoblast cells. The recombinant (r) bIFNtau had high antiviral activity (1 x 10 (8) IU/mg) and the molecular weight of rbIFNtau was estimated to be 23 kDa by Western blotting analysis. We investigated the biological effect of rbIFNtau on prostaglandin (PG) F(2alpha) synthesis in cultured bovine endometrial epithelial cells in the presence or absence of oxytocin (OT, 100 nM). rbIFNtau suppressed basal and OT-induced PGF(2alpha) production in a dose-dependent manner (1-1,000 ng/ml). These results showed that biologically active rbIFNtau was produced in the baculovirus expression system, and that rbIFNtau had the ability to suppress the synthesis of PGF(2alpha) from bovine endometrial epithelial cells.  相似文献   
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This study was conducted to improve the developmental ability of nuclear transfer (NT) embryos by using blastomeres from in vitro fertilized (IVF) embryos with high quality as donor cells. The IVF embryos selected at the 2-cell stage at 24-h postinsemination (hpi) and again at the ≥8-cell stage at 48 hpi (Selected-IVF-embryos) showed the highest blastocyst formation rate among embryos. When blastomeres from the Selected-IVF-embryos (Selected-NT group) or Nonselected-IVF-embryos (Non-selected-NT group) were used as donor cells for NT, the blastocyst formation rate in the Selected-NT group (25.6%) was significantly higher than that in the Non-selected-NT group (13.5%). When blastomeres from the Selected-IVF-embryos at 108 (contained many cells before cell division) and 126 hpi (contained many cells immediately after cell division) were used as donor cells for NT (108- and 126-NT groups, respectively), the 126-NT group showed a significantly higher blastocyst formation rate (32.1%) than the 108-NT group (16.8%). Embryo transfer of blastocysts in the 126-NT group showed that 11 of 23 recipients became pregnant; nine calves were obtained. For the NT embryos reconstructed using in vivo derived embryos, 9 of 20 recipients became pregnant; seven calves were obtained. These results indicate that the blastocyst formation rate of NT embryos can be improved by using blastomeres from IVF embryos selected at the early developmental stage, especially immediately after cell division, and that the resultant NT embryos have a high developmental ability to progress to term that is comparable to NT embryos reconstructed using in vivo derived embryos.  相似文献   
36.
We noted that ammonia nitrogen was not adsorbed by the cultivated layers of highly permeable paddy fields during the initial fertilization period, but reached the lower layers relatively early. In our study, we considered an exponential equation from an aqua-environmental perspective with the goal of obtaining good growth of rice plants in order to estimate the concentrations and integrated volume of ammonia nitrogen accompanying paddy percolation. Using this exponential equation, we were able to derive a relation between time and concentrations of paddy percolation water, and hypothesized that if percolation rates were less than 10 mm/day, percolation would have no effect on rice growth, while simultaneously helping to maintain the good water quality of the extra-paddy environment. We also clarified the differences between the potential ammonia nitrogen adsorption volume derived from the CEC value and the integrated amount of ammonia nitrogen water in soil, and considered the causes from the perspectives of solute movement and water movement. Electronic Publication  相似文献   
37.
Volcanogenous soils are widely distributed in Japan. Andosols, a group of volcanogenous soil, are known to show several physicochemical characteristics such as high porosity, presence of allophane, and high content of organic carbon (FitzPatrick 1980). The formation of Andosols is a very rapid process resulting from the large surface area of the volcanic ash-derived parent materials.  相似文献   
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ABSTRACT

Wheat (Triticum aestivum L.) grain yield is predicted to decrease in the future because of an increase in air temperature globally. To clarify the effects of the vernalization response gene in wheat to warmer winters, we compared dry matter production and grain yield between spring wheat ‘Asakazekomugi’ and its winter-type near-isogenic line (NIL) carrying different alleles of the vernalization response gene Vrn-D1 under early-, standard-, and late-sowing conditions. Under early-sowing conditions, dry matter production of the NIL carrying the winter allele of Vrn-D1, named Asa (Vrn-D1b), exceeded that of ‘Asakazekomugi’ from mid-March (after stem elongation in Asa (Vrn-D1b)) when the temperatures rose. Tiller number and leaf area index under early-sowing conditions were consistently higher in Asa (Vrn-D1b) than in ‘Asakazekomugi’ from mid-March onward. It was suggested that the early-sown ‘Asakazekomugi’ could not effectively absorb solar radiation to produce dry matter because of the acceleration of stem elongation caused by the Vrn-D1 gene during the cold season. The grain yield of Asa (Vrn-D1b) with early sowing was higher than with standard sowing. In contrast, the grain yield of ‘Asakazekomugi’ was lower in the early-sown crop than in the crop sown at the standard date. These results suggested that the higher grain yield of Asa (Vrn-D1b) than that of ‘Asakazekomugi’ under early-sown conditions could be due to Asa (Vrn-D1b) maintaining high dry matter production after the jointing stage by suppressing acceleration of growth caused by warm conditions after sowing.  相似文献   
40.
We investigated the effects of a low crude protein (CP) diet and a low CP diet supplemented with synthetic essential amino acids (EAA) on the meat quality of broiler chickens. Twenty‐one‐day‐old chickens were assigned to one of three diets: control, low CP (LCP), or low CP supplemented with EAA (ELCP). The chickens received these diets for 10 days. The shear force value (SFV) and free glutamate content of the Pectoralis major muscle were measured as indicators of the meat toughness and taste. The collagen and crude fat content of the muscle and the cross‐sectional area of myofibers were measured to evaluate the effects of the LCP and ELCP diets on meat toughness. The SFV of the ELCP group was 47% lower than that of the control group (P < 0.01). However, the LCP diet did not affect the SFV. The collagen and crude fat content were not affected by the dietary treatment. The cross‐sectional area was lower in the LCP and ELCP groups (P < 0.05) than the control group. The free glutamate content of muscle was not affected by the dietary treatment. Thus, a low CP diet supplemented with EAA is an effective means of producing tender meat.  相似文献   
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