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1.
The objective of this study was to evaluate the efficiency of gonadotropin releasing hormone (GnRH) and GnRH doses in synchronizing follicular wave emergence as a pretreatment for superovulation in cattle. Fourteen Holstein-Friesian cows 6 days from estrus were randomly assigned to receive 100 microg (n=4), 50 microg (n=5), or 25 microg (n=5) of GnRH. Superovulation was induced with injections of porcine FSH (pFSH) twice daily, decreasing the dose (total 42 AU) over 5 days beginning 2.5 days after receiving GnRH. On the 7th and 8th injections of pFSH, 750 microg of PGF(2alpha) was also given. With the exception of one cow that was given 50 microg of GnRH, ovulation was induced in all cows from the three groups and the new follicular wave emergence was observed. The total number of follicles for the 25 microg GnRH group was less than that observed for the 100 microg GnRH group (P<0.05), although there were no differences between the 100 microg, 50 microg and 25 microg GnRH groups with respect to the number of preovulatory follicles (>or=10 mm) and CL. The numbers of normal embryos were greater for the 25 microg GnRH group than the 100 or 50 microg GnRH groups (P<0.01); however, the numbers of ova/embryos did not differ significantly between the three groups. These results suggest that 25 microg of GnRH was sufficient to induce ovulation and follicular wave emergence. On day 6 of the estrous cycle, a reduction of the dose of GnRH to synchronize follicular wave emergence as a pretreatment for superstimulation promotes transferable embryos.  相似文献   
2.
The KELP protein of Arabidopsis thaliana (AtKELP), which binds to the Tomato mosaic virus (ToMV) movement protein in vitro, can interfere with cell-to-cell movement of the virus under transient overexpression conditions. In this study, we constructed expression plasmids encoding a fluorescent protein fused to AtKELP or to its homolog from Brassica, Nicotiana, Solanum, or Oryza species. When expressed transiently, all the AtKELP homologs inhibited the cell-to-cell movement of ToMV with different efficiencies. The results of domain swapping between two selected AtKELP homologs suggest the importance of combination between the N- and C-terminal half regions for high inhibitory function.  相似文献   
3.
A computational analysis of the nuclear genome of a red alga, Cyanidioschyzon merolae, identified 11 transfer RNA (tRNA) genes in which the 3' half of the tRNA lies upstream of the 5' half in the genome. We verified that these genes are expressed and produce mature tRNAs that are aminoacylated. Analysis of tRNA-processing intermediates for these genes indicates an unusual processing pathway in which the termini of the tRNA precursor are ligated, resulting in formation of a characteristic circular RNA intermediate that is then processed at the acceptor stem to generate the correct termini.  相似文献   
4.
The transverse shrinkage variation within trees was examined for five sugi cultivars. The within-tree trends of tangential shrinkage (α T) were different by cultivar, whereas radial shrinkage (α R) increased from pith to bark in most cultivars. The tangential/radial shrinkage ratio (α T/α R) decreased from pith to bark in most cultivars, because the radial variation of α R was larger than that of α T. The cultivars showed significant differences among cultivars in α T, α R, and α T/α R, but the difference among cultivars for α T/α R was smaller. The relationships between transverse shrinkage and microfi bril angle (MFA), basic density (BD), tree ring parameters, and modulus of elasticity were examined. The α T and α R showed positive relationships with BD, latewood percentage, latewood density, and modulus of elasticity, and negative relationships with MFA and ring width. The relationships with earlywood density were weak. Sugi exhibited variation in transverse shrinkage within stem and among cultivars, with the variation affected by MFA, density, and tree ring parameters. Part of this article was presented at the 56th Annual Meeting of the Japan Wood Research Society, Akita, Japan, August 2006, and the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, Japan, August 2007  相似文献   
5.
Using soft X-ray photography, two-dimensional observations were made of the water distribution within the green stem ofCryptomeria japonica D. Don. Variations in the distribution pattern of the wet area in the horizontal plane of the lower stem were described. The distribution patterns showed extreme variation among individual trees, with broad wet-area distribution types appearing, namely, the regularly distributed wet area and the irregularly distributed wet area. We defined five basic types of wet-area distribution patterns on the basis of their regularity or irregularity. It was concluded that the between-tree variation in the wet-area distribution causes the between-tree variation in the mean moisture content of the heartwood. The distribution patterns of the wet area were similar for individual trees within each plus-tree clone.Part of this paper was presented at 46th annual meeting of the Japan Wood Research Society at Kumamoto, April 1996  相似文献   
6.
We conducted histological observation of male germ cells and reproductive organs of the starspotted smooth-hound Mustelus manazo in Tokyo Bay to reveal any abnormality in male reproductive traits, as part of a study to elucidate the factors causing recent fluctuation in abundance of the population. Spermatogenesis proceeded in spermatocysts from the germinal zone in the ventral part of the testis to the degenerative zone in the dorsal part, where the spermatozoa were conveyed into the ciliated lumina of the attached terminal branches of the intratesticular ducts. The intratesticular ducts were classified from their terminal ends into branch, stem, and collecting tubules. The ducts formed in the germinal zone and grew as the spermatocysts developed. An opening formed through the wall of each of the most mature spermatocysts into a branch tubule; bundles of spermatozoa were evacuated through this opening into the branch and then the stem tubule and subsequently into the collecting tubules in the rete testis and the efferent duct connected to the epididymis. Spermatocysts that were unable to emit sperm because of failure of adhesion to the branch tubules were disorganized in situ, as were their spermatozoa. The collapsed spermatocysts seem to be cleared by hemophagocytosis with lymphocytes and leukocytes, which may have been recruited from the epigonal organ. There were no specific abnormalities in the spermatogenesis or the morphological structure of testes, which suggested that an abnormality of male reproductive traits was not the major cause of the recent fluctuation in the population abundance of this species. Details of the intratesticular duct system for sperm emission to the epididymis are the first findings in elasmobranchs worldwide.  相似文献   
7.
Graft perfusion with cold heparinized saline has known to induce ischemia and reperfusion injury in feline kidney transplantation. In this study, the effects of phosphate-buffered sucrose solution and heparinized saline solution on early kidney graft function were compared in feline kidney autotransplantation. Perfusion of grafts with or without hypothermic storage with chilled phosphate-buffered sucrose solution prevented ischemia and reperfusion injury despite a very short ischemic time. The results of our study suggest that phosphate-buffered sucrose perfusion and storage solution should be effective to reduce ischemia and reperfusion injury despite a very short ischemic time in feline kidney transplantation.  相似文献   
8.
An analysis of ionizing radiation-induced damage in peripheral lymphocytes has been employed to predict the prognosis of radiotherapy in terms of toxicity in normal tissues. Therefore, understanding the sensitivity of lymphocytes to high linear energy transfer (LET)-charged particles would be indispensable for utilizing charged particle therapy in veterinary medicine. However, the availability of such information is very limited. This study aimed to compare the radiosensitivity of feline T lymphocytes to gamma-rays (0.2 keV/microm) and 4 different types of charged particles with LET values ranging from 2.8 to 114 keV/microm. It was observed that the relative biological effectiveness, inactivation cross-section, and isodose-induced apoptosis increased in an LET-dependent manner. On the other hand, no difference in apoptosis frequency was observed in the cells exposed to an isosurvival dose of all the radiation types tested. This is the first study that demonstrates the LET dependence of cell killing and apoptosis induction in feline T lymphocytes. Our results suggest that lymphocytes can be effectively used to predict the prognosis of charged-particle therapy in cat patients.  相似文献   
9.
We investigated the fundamental behaviour of Chisan (check) dams in response to the presence or absence of impounded sediment with different levels of saturation. Large-scale model flume experiments were conducted by use of a model Chisan dam that had been backfilled with pumiceous clasts taken from the Sakurajima volcano in Kagoshima prefecture, Japan. In these experiments, the miniature dam was situated midway down the flume under different backfill sediment conditions and the basal pore-fluid pressure, normal flow depth, and impact load of the granular mass were carefully monitored. Saturated sediment with a volume of 0.6 m3 was released along the slope of the flume segment at 30° and excess pore-fluid pressure was generated, corresponding to a sediment velocity of approximately 4.8 m s?1. Direct collision of the sediment with the Chisan dam meant the peak impact loads of granular mass against the back surface of the dam exceeded 157 N in experiments without backfill sediment but were as low as 32.1 N in experiments with sediment. Accordingly, placing the backfill sediment substantially reduced peak impact loads. The sediment captured by the Chisan dams was also calculated. For experiments using saturated backfill sediment, the dam captured only 35 % of the material, indicating that most of the granular mass passed over the dam. However, in experiments without backfill sediment or with unsaturated backfill sediment, over 90 % was captured. Although Chisan dams with unsaturated backfill sediment lacked pocket space, almost equivalent granular masses were trapped in these experiments. On the basis of these results, we suggest that Chisan dams with unsaturated backfill sediment could effectively counter debris flow, reducing sediment loads along the streams draining Sakurajima volcano.  相似文献   
10.
To evaluate the bow variation in boxed-heart square timber of sugi (Cryptomeria japonica), bows from kiln-dried timber for five sugi cultivars with different longitudinal shrinkage trends were compared for two stem heights. Two general trends were observed, depending on the cultivar: (1) either the bow was larger at the lower than at the upper part of the stem, or (2) the bows at the lower and the upper parts of the stem were similar. In timber that had larger bow values, the gradients of longitudinal shrinkage were large across the radius and along the length of the timber. There was a positive relationship between the bow and longitudinal shrinkage. These results suggest that the bow variation between the timbers was caused by a variation in longitudinal shrinkage, which was affected by the microfibril angle. Furthermore, the bow was inversely proportional to the modulus of elasticity, which suggests that timber with a low modulus of elasticity is susceptible to a large bow due to large longitudinal shrinkage.  相似文献   
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