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Prolapse of vagina is one of the important maternal abnormalities during pregnancy in cattle and buffaloes. A field investigation was carried out on 26 Murrah graded buffaloes to study clinical characteristics of vaginal prolapse in buffaloes in Nepal. Fifty-seven percent of the 26 buffaloes with vaginal prolapse were either heifers or in first lactation. Sixty-five percent of the cases were in seventh month of pregnancy or later. About three quarters of the cases occurred between June and October. Twelve cases (63%) of the 19 animals excluding 7 heifers had a history of vaginal prolapse in previous gestations. A half of the buffaloes were showing prolapse of the vagina even when they were in standing position and showing moderate or vigorous straining. After the conventional treatments, twenty-three buffaloes retained the replaced vagina and calved normally. One animal aborted although the vagina was retained. Two buffaloes had severest degree of vaginal prolapse complicated with edema, injury and cyanosis, and they did not respond to the treatment. The two buffaloes had frequently recurrent prolapse and subsequently died. Early detection and prompt treatment may be imperative to control the vaginal prolapse in buffaloes.  相似文献   
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The aim of this study was to examine whether the nutritional state of cows peripartum was associated with the recovery of ovarian function and conception rates after synchronization of ovulation and fixed-time artificial insemination (OVSYNCH/TAI). The effect of the interval in days from calving to the first ovulation on conception rates after OVSYNCH/TAI was also investigated. Conception rates of cows after OVSYNCH/TAI (n=39) were 43.6%. The conception rates of cows with a body condition score (BCS) of 2.75-3.25 at 30 d postpartum and on the day of OVSYNCH treatment were significantly higher than in cows with a BCS < or =2.5 (P<0.05). The percentage of cows establishing ovarian cyclicity before 55 d postpartum in cows with a BCS of 2.75-3.25 at 30 d postpartum and on the day of OVSYNCH treatment were significantly higher than in cows with a BCS < or =2.5 (P<0.05). The conception rates after OVSYNCH/TAI in cows which recovered ovarian cyclicity within 34 d postpartum were significantly higher than in cows with first ovulation > or =56 d (P<0.05). These results indicated that the nutritional state in cows peripartum influenced the conception rates after OVSYNCH/TAI and the postpartum ovarian cyclicity and also suggested that the conception rates after OVSYNCH/TAI decreased in cows with delayed recovery of ovarian cyclicity.  相似文献   
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This study investigated the relationship between the cellulose crystal lattice strain (crystalline region) and the macroscopic surface strain in specimens of Chamaecyparis obtusa wood under repeated uniaxial tension stress in the fiber direction. Changes in the strain of the crystal lattice were measured from the peak of (004) reflection using the transit X-ray method. The macroscopic surface strain of each specimen was measured with a strain gauge. In both loading and unloading, the surface strain changed linearly with changes in stress. However, crystal lattice strain was not linear but exhibited changes along a curve with changing stress. Under stressed conditions, the crystal lattice strain was always less than the surface strain, regardless of the frequency of repetition in the loading and unloading cycle. The ratio of the crystal lattice strain to the surface strain showed a negative correlation for stress in both loading and unloading. That is, the ratio decreased with increasing stress, and finally tend to converge to a specific value. The ratio (I/I 0) between the diffracted intensity (I 0) in the (004) plane in the unloaded condition and the diffracted intensity (I) in the (004) plane in the loaded condition tend to converge on a specific value with increasing frequency of repetition. When the substantial tension Young’s modulus of the wood in the longitudinal direction decreased, the ratio of the strain of the crystal lattice to the surface strain also decreased. Moreover, the ratio decreased with increasing microfibril angle of the specimen.  相似文献   
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Balenine is one of the endogenous imidazole dipeptides. It is composed of beta-alanine and 3-methyl-l-histidine, which exist mainly in the muscles and the brain. The exact biological properties of balenine are still not well known, although the antioxidant activity of carnosine, another imidazole dipeptide, is known. In this study we investigated whether balenine exhibits antioxidant activity. It was found to decrease the superoxide anion (O2) and increased hydrogen peroxide (H2O2) generation. We found that SOD activity increased in balenine-treated C2C12 myotubes, although balenine did not increase expression of SOD mRNA. On the other hand, there were no changes in other antioxidant enzymes, CAT and GPX activity, and mRNA levels. In an in vitro assay, the direct activation of SOD treated by balenine was significantly higher than with carnosine treatment. Moreover, balenine constituent amino acids did not have the ability to activate SOD. Our results suggest that balenine contributes to antioxidant effects through activation of SOD.

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This study was designed to clarify the characteristics of changes in plasma concentrations of reproductive hormones in heifers from birth to puberty. Weekly or daily hormonal changes were observed in 39 heifers. Daily changes in the concentration of follicle-stimulating hormone (FSH) demonstrated a consistent cycle of hormone changes over a 7- to 8-day period in heifers from approximately 10 days to 9 months old. Weekly changes in reproductive hormones showed that there were three brief periods in heifers between birth and puberty in which dramatic changes occur. The first period was the first week after birth, during which a reciprocal relationship between steroid hormones and gonadotropins was observed. At birth, the concentrations of steroid hormones were higher than those at any other age. These hormone levels rapidly decreased within the first week after birth. Gonadotropin levels, however, increased from birth to 1 week of age. The second period of major change was at approximately 4 weeks of age when there was an increase in the concentrations of luteinizing hormone (LH), estradiol-17beta, testosterone, and immunoreactive inhibin. The third period was the last 5 weeks before the first ovulation, when there was an increase in the concentrations of estradiol-17beta followed by an increase in (LH). These results suggest that regular hormone changes start from 10 days after birth and that the periods from birth to 4 weeks of age and the last 5 weeks before the first ovulation in heifers are important to the development of reproductive functions before puberty.  相似文献   
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The effects of defatted safflower seed extract and its phenolic constituents, serotonin derivatives, on atherosclerosis were studied. Ethanol-ethyl acetate extract of safflower seeds (SSE) inhibited low-density lipoprotein (LDL) oxidation induced in vitro by an azo-containing free-radical initiator V70 or copper ions. Two serotonin derivatives [N-(p-coumaroyl)serotonin, CS; N-feruloylserotonin, FS] and their glucosides were identified as the major phenolic constituents of the extract. The study with chemically synthesized materials revealed that a majority of the antioxidative activity of SSE was attributable to the aglycones of these two serotonin derivatives. Orally administered CS and FS suppressed CuSO(4)-induced plasma oxidation ex vivo. Long-term (15 week) dietary supplementation of SSE (1.0 wt %/wt) and synthetic serotonin derivatives (0.2-0.4%) significantly reduced the atherosclerotic lesion area in the aortic sinus of apolipoprotein E-deficient mice (29.2-79.7% reduction). The plasma level of both lipid peroxides and anti-oxidized LDL autoantibody titers decreased concomitantly with the reduction of lesion formation. Serotonin derivatives were detected as both intact and conjugated metabolites in the plasma of C57BL/6J mice fed on 1.0% SSE diet. These findings demonstrate that serotonin derivatives of SSE are absorbed into circulation and attenuate atherosclerotic lesion development possibly because of the inhibition of oxidized LDL formation through their strong antioxidative activity.  相似文献   
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