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81.
A 10-month-old cat was diagnosed with congenital subvalvular aortic stenosis. To resolve its hypoxia, oxygen therapy was administered a couple of times a week during two months. The oxygen partial pressure in the chamber was maintained between 30 and 35%, and the time for one procedure was 12-24 hr. The animal died due to severe respiratory failure. At necropsy, the lungs were voluminous and had a rubbery texture. Histologically, large type II pneumocytes with occasional atypia had diffusely proliferated within the lungs. Interstitial fibrosis was not observed, although some alveolar septa were thickened along with fibrinous exudates and neutrophilic infiltration. The histology of these lesions was consistent with diffuse alveolar damage (DAD), which might have been partially due to oxygen toxicity.  相似文献   
82.
The purpose of the present study was to investigate the effect of milk in the early stage of lactation on the maturation of cholinergic neurons in the cerebral cortex of rats. Pups were removed from their mothers immediately following parturition and placed with foster dams at days 5–7 of lactation. At days 18 and 56 after birth, the activity of choline acetyltransferase (ChAT), an enzyme responsible for acetylcholine synthesis, in different areas of the cerebral cortex was examined by high‐performance liquid chromatography electrochemical detection. In the frontal and hindlimb/parietal regions of the cerebral cortex, the lack of early milk significantly decreased ChAT activity at days 18 and 56. There was no effect on gains in the body or brain weight of infants. ChAT activity in the occipital area tended to be lower in the early milk‐deprived rats. The intake of early milk potentially contributes not only to nutrients for the growth of newborn infants, but also to the functional maturation of the cholinergic neurotransmission system in a region‐specific manner.  相似文献   
83.
In the previous paper (1), liming an acid humus volcanic ash soil resulted in the formation of humic acids combined with calcium, but had no significant effect on acid brown forest soils containing humic acids of a lower degree of humification. Subsequently, the authors examined the humus composition of the soils treated with calcium acetate, and conducted some experiments on the combination reaction between humic acid and calcium ions. The results obtained are presented in this paper.  相似文献   
84.
Remote sensing, in particular satellite imagery, has been widely used to map cropland, analyze cropping systems, monitor crop changes, and estimate yield and production. However, although satellite imagery is useful within large scale agriculture applications (such as on a national or provincial scale), it may not supply sufifcient information with adequate resolution, accurate geo-referencing, and specialized biological parameters for use in relation to the rapid developments being made in modern agriculture. Information that is more sophisticated and accurate is required to support reliable decision-making, thereby guaranteeing agricultural sustainability and national food security. To achieve this, strong integration of information is needed from multi-sources, multi-sensors, and multi-scales. In this paper, we propose a new framework of satellite, aerial, and ground-integrated (SAGI) agricultural remote sensing for use in comprehensive agricultural monitoring, modeling, and management. The prototypes of SAGI agriculture remote sensing are ifrst described, followed by a discussion of the key techniques used in joint data processing, image sequence registration and data assimilation. Finally, the possible applications of the SAGI system in supporting national food security are discussed.  相似文献   
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86.
A novel angiotensin‐converting enzyme (ACE) inhibitory peptide was isolated and purified from chicken bone extract by enzymatic digestion. The peptide was defined as an ACE inhibitor, and it demonstrated antihypertensive activity following oral administration to spontaneously hypertensive rats (SHRs). The results of this study suggest that peptides derived from an extract of chicken bones, administered orally, have the ability to reduce the blood pressure of SHRs significantly over a short period of time (3 h). Moreover, the blood pressure then remains low for 3 h. This peptide derived from chicken bones may therefore have great value as a short‐term remedy for chronic conditions such as high blood pressure. The amino acid sequence of the peptide was YYRA (Tyr‐Tyr‐Arg‐Ala), which was the origin of the Ig heavy chain V region (27–30 position). The IC50 value of its synthetic peptide was 33.9 μg/mL. We suggest that the ACE inhibitory and antihypertensive peptides derived from chicken bone extract may contribute to develop physiologically functional foods or improve food functionality.  相似文献   
87.
Plant Foods for Human Nutrition - Our previous study showed anti-influenza virus activity in adlay tea prepared from adlay seeds, naked barley seeds, soybean, and cassia seeds. In this study, we...  相似文献   
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89.
We conducted laboratory experiments to examine the effects of turbidity on the survival of red sea bream Pagrus major and ayu Plecoglossus altivelis altivelis larvae when exposed to either visual (jack mackerel juveniles) or tactile (moon jellyfish) predators. The experiments were conducted in 30-l tanks with three different levels of turbidity obtained by dissolving 0, 50, or 300 ppm kaolin. Predators were introduced to the experimental tanks followed by larvae of either red sea bream (mean ± standard deviation 6.1 ± 0.3 to 11.4 ± 2.1 mm standard length) or ayu (6.6 ± 0.3 and 24.4 ± 1.8 mm). When exposed to jack mackerel, the mean survival rate of larvae was significantly higher in 300 ppm treatments compared with the other turbidity levels. When exposed to moon jellyfish, however, there was a less marked difference in the survival rates among different turbidity treatments. Survival rates of ayu larvae exposed to moon jellyfish were generally lower than those of red sea bream. Our study indicates that anthropogenic increases of turbidity may increase the relative impact of jellyfish predation on fish larvae.  相似文献   
90.
The Malabar grouper Epinephelus malabaricus is an important candidate species for commercial aquaculture in tropical and subtropical areas. In nature, this species requires more than 10 years to change sex from female to male and have active spermatogenic tissues in the testis. Thus, it is essential to find a means of producing sperm for seed production. This is the first report of artificial sex change in underyearling E. malabaricus . Female E. malabaricus with immature ovaries at 144 days post-hatch (DPH) were fed a diet with 17α-methyltestosterone (MT) at 50 μg g−1 diet for 6 months. Sex change occurred in most of the treated fish, which had testis with all stages of spermatogenic germ cells including spermatozoa. In contrast, most of the control fish had immature ovaries. These results, which reveal that germ cells in the underyearling grouper have the ability to produce spermatozoa in response to exogenous androgen, demonstrate that sex change can be artificially induced during ovarian development.  相似文献   
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