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101.
Physical, chemical, and biological properties of S-allylcysteine (SAC) were investigated. SAC showed stable properties under tested conditions, and its acute/subacute toxicity was very minor in mice and rats (LD(50) value >54.7 mM/kg po; >20 mM/kg ip). The pharmacokinetics of SAC was investigated after oral administration of garlic supplement containing SAC to human volunteers. SAC from garlic consumption was rapidly absorbed from the gastrointestinal tract, however, the half-life and excretion time were more than 10 h and 30 h, respectively.  相似文献   
102.
In a series of studies, development of a new aqueous emulsion-type adhesive for use with wood or paper, which does not release formaldehyde or volatile organic solvents, was attempted. For the purpose of increasing both initial and final adhesive strengths, we selected a system consisting of acrylic monomers copolymerized with functional monomers such as diacetone acrylamide and some cross-linking agents such as dihydrazide or polymeric methylene diphenyl diisocyanate (pMDI). It was found that dihydrazide cross-linker was effective for both the initial and final adhesive strengths, suggesting contribution of hydrazone bonds to the bonding strengths. Cross-linking with pMDI might be slow and was not important in the initial bonding. However, its cross-linking effect might develop gradually, because the adhesive showed good final strengths using pMDI as a cross-linker.  相似文献   
103.
ABSTRACT:   The feeding habits of Lampanyctus jordani , an abundant mesopelagic fish in the subarctic North Pacific, was examined based on the stomach contents of 721 specimens collected over the continental slope off the Tohoku area, Pacific coast of northern Japan during April and October from 1996 to 1998. The prey items comprised mainly crustaceans such as copepods, amphipods, euphausiids and decapods. Euphausiids were the most important items in the diet both during April and October. During April, when the annual maximum of zooplankton biomass occurred and the Oyashio Intrusion Current prevailed, L. jordani fed intensively and consumed a high proportion of Euphausia pacifica . These seasonal variations also influenced the feeding intensity and dietary diversity. Feeding intensity, measured by the stomach contents index, was higher during April than October, reflecting the higher biomass of zooplankton in the Tohoku area during spring. The dietary diversity of L. jordani was lower during April than October, indicating that L. jordani shifted to a wider variety of prey when the availability of E. pacifica was limited.  相似文献   
104.
[目的]我国草莓以设施栽培为主,病虫发生多且严重,施用农药是草莓生产的重要环节.为了给草莓病虫害科学防控及农药登记提供参考,对目前我国草莓用农药登记现状进行分析.[方法]根据中国农药信息网登记的草莓用农药信息,对登记农药的种类、数量、防治对象、剂型及毒性进行统计分析.[结果]结果表明,截至目前,我国草莓用农药登记产品仅...  相似文献   
105.
For truncation selection on a proportion‐defined trait, an approximate expression for the true truncation point is currently available, which has been derived assuming that the component traits follow a curtailed normal distribution. This note deterministically examines the validity of the approximate expression in some details. We show that the value defined by the approximate expression is equivalent to that derived from an approximation to the true probability density function for the proportion trait of concern. We also show that the validity of the approximate expression is definitely dependent on the magnitude of the lower limit in the definite integral involved in the true probability density function for the proportion trait. We reveal some properties of the lower limit concerning its maximum and minimum. We indirectly assess the adequacy of the approximate expression under the settings of the altered coefficients of variation for the component traits and the changed correlation between them. The results indicate that the true value of the truncation point can be numerically represented quite sufficiently by the approximate expression, when the coefficients of variation are approximately below 25% and the positive correlation is not extremely high.  相似文献   
106.
There are a number of reports documenting skeletal development in groupers, but surprisingly little is known about muscle development. We have documented muscle development in the seven-band grouper Epinephelus septemfasciatus (Thunberg), focusing primarily on the cranial muscles from 0 days post-hatching (dph) to 28 dph, using a modified whole mount immunohistochemical staining method. The eye muscles developed first followed by the cheek muscles, which completed development prior to first feeding. The muscles associated with the opercle and the levator internus 1 developed gradually and were not linked to first feeding. Later, between 12 and 16 dph, the muscle composition in the dorsal branchial arches changed to the adult form. We observed a number of cultured larvae that exhibited abnormal musculature in the body and jaw. Our results provide the first documentation of muscle development in larval seven-band grouper. This information can be used to detect abnormalities during development and provide a marker to assess the effect of changes in larval rearing techniques.  相似文献   
107.
This experiment aimed to determine the changes in chemical composition, fermentation profile, in situ disappearance characteristics, and nutrient losses of ensiled total mixed ration (TMR) containing steam‐flaked corn or brown rice (BR) during storage. TMRs for dairy cows, containing either steam‐flaked corn or BR at 31.9% with 15.2% rye silage, 40.5% alfalfa silage, 5.0% beet pulp and 7.0% soybean meal, were prepared (dry matter (DM) basis). Each TMR was placed in a plastic drum silo, stored at 23°C in an air‐conditioned room and sampled 0, 7, 14, 30, 90 and 210 days after preparation. In both grain sources, the fermentation products increased, while DM and starch storage losses increased and starch content greatly decreased during storage. The rapidly degradable fraction and effective ruminal degradability of DM, crude protein and starch increased during storage. These changes of dietary characteristics were large during 30 days of storage, but small after 90 days of storage. Replacing corn with BR led to increased fermentation products, starch loss and effective ruminal degradability of the ensiled TMR. These results indicate that the ensiling process of TMR changes the dietary characteristics and replacing corn with BR in TMR had a large impact on these dietary characteristics.  相似文献   
108.
109.
Cellulose powders were pulverized by an ultra high-pressure counter-collision treatment in an aqueous suspension state, and then used in composites with vinyl polymers and graft copolymerized with methyl methacrylate using ceric ion initiator. The influence of freeze-drying methods after microfibrillation of cellulose was visualized by scanning electron microscopy (SEM). The coalescence of microfibrillar structures was observed to increase easily reflecting the freeze-drying conditions. While the degree of microfibrillation was unsatisfactory for use as fillers in preparing polymer-nanocellulose composites, the situation was found to be rectified with the use of a proper kneading technique. The roles of microfibrillated cellulose in processes producing bio-nano-composites suitable for practical uses were studied through SEM observations and measurements of physical properties. The characteristics of the successive graft copolymerization were studied through examining the monomer conversion and the grafting effi- ciency. The significant improvement in the grafting became apparent in response to the counter-collision pretreatment. Dynamic viscoelastic properties of the molded sheets of the grafted products were studied to measure the effects of the graft copolymerization compared with the corresponding physically blended material and neat poly(methyl methacrylate). The grafting reaction resulted in composites with much higher heat-resisting properties than those obtained for the latter two.  相似文献   
110.
The dominance genetic effects for reproductive and calf growth abilities in the practical Japanese Black populations were examined using average information (AI) algorithm restricted maximum likelihood (REML) under animal models. The reproductive traits were observed in Japanese Black cattle maintained at Tottori and Okinawa prefectures, and growth traits of calves were observed in cattle at Okinawa. The average of dominance relationships in Tottori ranged from 0.2 to 0.4%, while the level in Okinawa was lower and sparse compared with Tottori. The proportions of the dominance variances to sum of additive and dominance variances () were all 0.02 for reproductive traits in Tottori. In contrast, the proportion was 0.02–0.64 in Okinawa regardless of the level of dominance relationships. These proportions suggested that the dominance might affect the expression of calving interval, days open and gestation length in Okinawa, where breeding units were spread over many islands. Although the dominance variances could not estimate birthweight, w as 0.34 for calf market weight and 0.27 for average daily gain from birth to calf market in Okinawa. These values also suggested that the dominance might affect the early growth of calves. In the near future, genetic relationships will become more complicated with continuation of the current selection and mating systems. Therefore, genetic evaluation accounting for dominance effects would be necessary for particular traits and populations.  相似文献   
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