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51.
Foam stability is an important quality trait of beer. Our previous results of two-dimensional gel electrophoresis (2DE) analyses of beer proteins implied a relationship between barley dimeric alpha-amylase inhibitor-1 (BDAI-1) and beer foam stability as judged by the NIBEM-T analyzer. To develop a novel prediction method of beer foam stability under different conditions of barley cultivar and malt modification, multiple linear regression analysis was applied. The spot intensities of major beer proteins on 2DE gel were quantified and used as explanatory variables. The foam stabilities of 25 beer samples each brewed from malt with different malt modification in one of the three cultivars (cultivars A, B, and C) were explained by the spot intensities of BDAI-1 at the 5% significance level ( r = 0.421). Furthermore, two other major protein spots (b0 and b5) were observed on the 2DE gels of Japanese commercial beer samples with different foam stability. Then, multiple regression for foam stability was calculated using these three spot intensities as explanatory variables. As a result, 72.1% of the beer foam stability in 25 beer samples was explained by a novel multiple regression equation calculated using spot b0 and BDAI-1 as positive explanatory variables and spot b5 as a negative variable. To verify the validity of the multiple regression equation and the explanatory variables, the beer foam stability in practical beer samples was analyzed. As a result, 81.5% of the beer foam stability in 10 Japanese commercial beer samples was also explained by using spot b0 and BDAI-1 as positive explanatory variables and spot b5 as a negative variable. Mass spectrometry analyses followed by database searches revealed that protein spots b0 and b5 were identified as protein Z originated from barley and thioredoxin originated from yeast, respectively. These results confirm that BDAI-1 and protein Z are foam-positive factors and identify yeast thioredoxin as a possible novel foam-negative factor.  相似文献   
52.
The objective of this study was to investigate the changes in secretion of inhibin and cellular localization of the inhibin alpha and inhibin/activin (beta(A) and beta(B)) subunits in male Japanese quail from 1 to 7 weeks after hatching. The post-hatch profile of plasma luteinizing hormone (LH), immunoreactive (ir) inhibin and testosterone were measured by radioimmunoassay. Testes were immunostained by the avidin-biotin-peroxidase complex method (ABC) using polyclonal antisera raised against inhibin alpha, inhibin/activin beta(A) and inhibin/activin beta(B) from one week of age to sexual maturity. Testicular weight increased gradually until 4 weeks and abruptly increased from 5 weeks of age onwards. The plasma concentrations of LH and ir-inhibin increased significantly at 5 weeks of age, and the plasma concentration of testosterone increased significantly at 6 weeks of age. Pituitary contents of LH showed a steady increase until 6 weeks of age and then abruptly increased at 7 weeks of age. Coincident to the increase in plasma testosterone, the testicular contents of testosterone significantly increased from 5 weeks through sexual maturity. Immunohistochemically, localization of the inhibin/activin alpha, beta(A) and beta(B) subunits was found in the Sertoli and Leydig cells at all ages of development from one week of age to sexual maturity. These results suggest that Sertoli and Leydig cells are the major source of inhibin secretion during development in male Japanese quail.  相似文献   
53.
To clarify the cellular source and secretory pattern of inhibin in the Japanese quail during follicular development, the plasma concentrations of immunoreactive (ir) inhibin were measured from 1 to 7 weeks after hatching. Localization of the inhibin/activin alpha, beta A and beta B subunits was investigated by immunohistochemistry. To monitor development of the pituitary and ovarian functions, the plasma luteinizing hormone (LH) and progesterone concentrations were also measured. Ovarian weight increased gradually until 6 weeks of age and then abruptly increased at 7 weeks of age just at the onset of egg production. Plasma concentrations of LH increased significantly at 6 weeks of age. The plasma concentrations of ir-inhibin and progesterone and the pituitary contents of LH also increased significantly at 7 weeks of age. Immunohistochemically, the inhibin/activin alpha, beta A and beta B subunits were localized in the granulosa cells of all follicles during different stages of development from 1 to 7 weeks after hatching. The inhibin alpha, beta A and beta B subunits were also found in the interstitial cells but not theca cells of all follicles. These results demonstrated that the plasma concentrations of ir-inhibin of the female Japanese quails rose with ovarian development. The immunohistochemical results suggested that granulosa and interstitial cells are the major source of ovarian inhibins in female Japanese quails.  相似文献   
54.
Characteristic daily increases in the plasma levels of luteinizing hormone (LH) are present every afternoon during lactation in golden hamsters. The objective of this study was to investigate the effect of the diurnal rhythm of increases in LH on expression of nerve growth factor (NGF), its receptors trkA and p75 and inhibin alpha-subunit in the ovarian interstitial cells of lactating golden hamsters. Both lactating and non-lactating groups of postpartum golden hamsters were used in this study. The expression of NGF, its receptors trkA and p75 and inhibin alpha-subunit were determined by immunohistochemistry. Positive staining of NGF, trkA and p75 was found in the interstitial cells of the lactating group, and no immunoreactivity for NGF, trkA or p75 was observed in the ovarian interstitial cells of the non-lactating group. In addition, immunostaining of inhibin alpha-subunit was also observed in the interstitial cells of the lactating group but not in those of the non-lactating group. Immunostaining of the inhibin/activin beta(A)- and beta(B)-subunits was observed in the granulosa cells of antral follicles, but not in the interstitial cells of the lactating and non-lactating animals. These results suggest that the diurnal rhythm increases in LH can induce expression of NGF, trkA, p75 and inhibin alpha-subunit in the ovarian interstitial cells of lactating golden hamsters and that NGF, its receptors trkA and p75 and inhibin alpha-subunit may have the capacity for autocrine or paracrine modulation of interstitial cell differentiation in golden hamsters.  相似文献   
55.
To investigate the androgenic effect of Kaempferia parviflora (KP), a Thai herbal plant, adult male rats were randomized into control and KP-treatment groups. Rats were treated orally with water in the control group and with 1,000 mg/kg/day of KP in the treatment group for 45 days. Blood samples were collected on days 10, 20, 30 and 45 for measurement of the serum follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone, progesterone and corticosterone levels. The reproductive and non-reproductive organs were dissected on day 45 and weighed. Mating behavior was also observed on days 20 and 30. Body weight was measured throughout the study period. The results showed that KP induced an increase in body weight compared with the controls. There were no significant differences in the weights of either reproductive (testis, seminal vesicle plus coagulating gland, levator ani muscle plus bulbocarvernosus muscle and glans penis, except the prostate gland) or non-reproductive organs (kidney, adrenal gland and gastracnemius muscle). There were no significant differences in serum levels of either FSH or LH between the two groups. The serum testosterone and progesterone levels were insignificantly lower in the KP group during the first 30 days. The serum corticosterone levels in the KP group were lower than those in the controls throughout the study period and were significantly low on days 20 and 30. There were no significant changes in mating behavior in the rats treated with KP. Although KP affected the body weight and serum corticosterone level, it did not affect mating behavior, reproductive and non-reproductive organ weights or hormones related to the reproductive system in the adult male rats. Therefore, we conclude that the testosterone-like effect of KP did not disturb the hypothalamic-pituitary-testicular axis or male reproduction.  相似文献   
56.
In China, the first Przewalski’s horse (Equus przewalskii) group was released in Kalamaili Ungulate Protected Area in Xinjiang, in August 2001. The objective of this study was to investigate reproduction and development of released Przewalski’s horses in Xinjiang, China from 2002 to 2006. Twenty-four descendants were naturally born, average reproduction rate was 38.7%, and average survival rate of foals was 69.1% in this interim. Frequent alternation of the leading stallion and infertility in female horses due to environmental factors were main causes for the low reproduction rate. The infant mortality rate of released Przewalski’s horses was 25.0%, and 83.3% of death in infants was due to the leading stallion infanticide. The released Przewalski’s horses exhibited seasonal breeding, 70.8% of infants were born in May and June. The fertility rates were 8.3% in April and 37.5% in May, which were lower compared to those of the captive Przewalski’s horse groups (18.3% and 44.3%, respectively). Furthermore, the fertility rate in June was 33.3% and higher than the captive groups (18.3%). These findings showed that the breeding peak of the released Przewalski’s horse groups was later than the captive groups, and suggested that the altered survival environment and food supplies were the main reasons contributing to the delayed breeding peak.  相似文献   
57.
Spontaneously Diabetic Torii (SDT) fatty rats, made by introducing the fa allele of the Zucker fatty rat into the SDT rat genome, represent a new model of obese type 2 diabetes. SDT fatty fa/fa (SDT fatty) rats exhibit overt obesity, hyperglycemia, and hyperlipidemia from about six weeks of age, and this is associated with hyperphagia by an induced disorder of leptin action. The present study was conducted to elucidate whether suppression of hyperphagia can improve reduce abnormalities in SDT fatty rats. SDT fatty rats were subjected to pair-feeding with SDT fatty +/ + (SDT) rats from 6 to 26 weeks of age, and the effects on metabolic parameters and diabetic complications were assessed. Body weights of the pair-fed rats were similar with those of SDT rats during the experimental period. Improvement of hyperglycemia or hypertriglyceridemia was observed from 8 to 16 or 12 weeks of age in the pair-fed rats, but hypercholesterolemia was not entirely improved during the experimental period. We also examined mRNAs expression in liver, and found that the expression associated with glyconeogenesis, such as glucose-6-phosphatase (G-6-Pase) and phosphoenolpyruvate carboxykinase (PEPCK), tended to decrease in the pair-fed rats, and the mRNA expression of hydroxymethylglutaryl-CoA (HMG-CoA) was elevated. Renal parameters, such as blood urea nitrogen and urinary albumin excretion, were improved in the pair-fed rats. The incidence or progression of diabetic complications, such as renal lesions and cataract, was reduced. In conclusion, suppression of hyperphagia in SDT fatty rats was effective in temporally improving hyperglycemia or hypertriglyceridemia, and reducing the incidence or progression of diabetic complications, but was ineffective in reducing hypercholesterolemia.  相似文献   
58.
To obtain basic knowledge about selecting horses for therapeutic riding, the influence of equine conformation on rider oscillation and relationships between these factors and the evaluation on horses as the therapeutic riding were studied. Thirty-five riding horses were used. Equine conformation was estimated by 24 indices. Rider oscillation was measured by an accelerometer fixed at the rider’s waist. The spatial position of the oscillation was estimated by a double integration of the acceleration. Horses were evaluated for therapeutic riding by a Riding for the Disabled Association instructor as a rider. Evaluations were on a scale of 1 to 5, with 5 being the highest score for 27 items. Horses were classified into 4 groups: the short and narrow (SN), short and wide (SW), tall and narrow (TN), and tall and wide (TW). The frequencies of rider oscillation both at walk and trot were higher (P<0.01), and the vertical (P<0.01) and longitudinal (P<0.05) amplitudes at trot were smaller, on short horses than on tall horses. The vertical amplitude at walk was smaller (P<0.05) and the lateral amplitude at trot was larger (P<0.01) on wide horses than on narrow horses. Short horses could be used for the rider who requires side walkers. Wide horses could be used for relieving muscular tension and for the rider who could not maintain good balance on the horse. Short and wide horses should be suitable for therapeutic riding.  相似文献   
59.
The inheritance of gramine indole alkaloid was studied in F1 and F2 generations derived from crosses between wild ( Hordeum vulgare subsp. spontaneum) and cultivated ( H. vulgare subsp. vulgare) barley at adult stage in the field. The means of gramine content were very low in F1s and F2s in April and May. The ratio of progeny containing gramine to those without gramine (near zero or undetectable) fit a mono-genic or di-genic model in F2 generation. However, the content of gramine might be controlled by minor genes in the gramine-containing plants. The direction of dominance was toward lower gramine content. The averages of dominance ( h/d) in F1 and F2 ranged from partial to complete. Broad-sense heritabilities were high (0.70 to 0.77). The usefulness of hybrids for breeding aphid resistance and possibility increasing palatability of grazing pasture for sheep and cattle is discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
60.
Methanolic extracts of 79 Malaysian plants representing 42 families were assessed for antinematodal activity against Bursaphelenchus xylophilus using a fungal-feeding assay. Extracts of 27 plants from 19 families showed antinematodal activity, while 52 species were inactive. Five extracts (Sauropus androgynus, Eugenia polyantha, Areca catechu, Piper betle and Piper nigrum) exhibited very strong activity against Bursaphelenchus xylophilus at a minimum effective dose (MED) of 0·625 mg per ball. Strong antinematodal activity (MED: 1·25–2·5 mg per ball) was shown by the extracts of Spondias cyntherea, Codiageum variegatum, Euodia glabra and Cicca acida. Eleven extracts (Carica papaya, Ipomoea aquatica, Ocimum basilicum, Leea gigantea, Pithecellobium jiringa, Crypteronia paniculata, Myristica fragrans, Murraya koenigii, Leucaena leucocephala, Melastoma malabathricum and Morinda citrifolia) demonstrated moderate activity between MED of 5 and 10 mg per ball, and weak activity was observed in seven extracts (Ipomoea batatas, Cymbopogon citratus, Garcinia atroviridis, Psophocarpus tetragonolobus, Tamarindus indica, Allium odorum and Stenochalaena palustris). © 1997 SCI  相似文献   
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