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71.
Whole animal transepithelial potentials (TEP) of yearling coho salmon (Oncorhynchus kisutch) in fresh water and after transfer to seawater were recorded throughout parr-smolt transformation (smoltification) from February to August 1984, along with plasma Na+ and Cl concentrations and osmolality. Based on plasma ion regulation in seawater, the yearling coho in this study completed smoltification and attained sea-water adaptability in April. TEP in freshwater fish decreased (became inside-negative) after smoltification, and the TEP increased significantly (P < 0.01) after seawater transfer. When fish were transferred into seawater, thyroxine increased TEP of the transferred smolts by approximately 30% over the control level (P < 0.01) in April, but this did not occur when freshwater postsmolts were transferred in July and August. Hypophysectomy increased TEP (P < 0.01) in fresh water; it did not affect the TEP of the fish after seawater transfer. Ovine prolactin (3 g/g body weight) implanted into seawater-adapted fish caused a reduction in TEP (P < 0.01) when fish were exposed to fresh water. Whole-animal TEP appears to provide a valuable index of the completion of smoltification (April–May) and a useful tool for investigating the endocrine control of salmonid osmoregulation.  相似文献   
72.
Acephate, amitraz, chlorpyrifos and formetanate hydrochloride were applied to orange trees. Test plots were treated at the maximum dose rates currently permitted in California in order to determine the consequent residues on and in the fruits. Applications were made with a low-volume airblast sprayer and used 0.94 klitres of spray per hectare. Fruit samples were collected at or near the legally prescribed California fruit-harvest waiting intervals. All residues were below the US tolerances for whole fruit. Analytical procedures for the gas chromatographic analysis of intact amitraz and formetanate and of 2,4-xylidine residues, without the necessity for derivative formation, are presented.  相似文献   
73.
Feline granulocyte colony-stimulating factor (G-CSF) with an N-terminal histidine hexamer tag was expressed as inclusion bodies in E. coli. The G-CSF solubilized in 6 M guanidine solution was absorbed onto a Ni-NTA column and, after washing with decreasing concentrations of guanidine, eluted with imidazole in a soluble and apparently pure form. The activity of the recombinant feline G-CSF was 3×106 U/mg protein, as assayed by its stimulatory effect on NFS-60 cell proliferation. When a low level of purified feline G-CSF was administered once a day for two successive days to cats, the number of neutrophil increased 4-fold while the levels of other blood cell types remained virtually unchanged. Daily administration of G-CSF for a total of 11 days led to a more than 10-fold increase in neutrophils, an 8-fold increase in the number of monocytes and 2-fold increase in lymphocytes. No severe side effects or antibody production was observed in cats after administration of G-CSF.  相似文献   
74.
Changes in the aroma of sake during aging were investigated by aroma extract dilution analysis (AEDA) and quantitative analysis using the stir bar sorptive extraction method. In AEDA, more odor zones were detected in aged sake than in fresh sake. The dilution factors of aldehydes, polysulfides, and some esters were greater in the aged sake, and their increase during aging was confirmed through a quantitative analysis of sake stored for 0-35 years. Among these compounds, 3-methylbutanal, methional, and dimethyltrisulfide (DMTS) were present in aged sake at concentrations exceeding their odor thresholds, and the highest odor active value was observed for DMTS. Sensory tests showed that supplementation with DMTS contributed to both the total odor intensity and the sulfury odor of aged sake aroma.  相似文献   
75.
We used a modified yeast-based human estrogen receptor alpha (ER alpha) bioassay to determine the estrogenic activity in 22 kinds of diets for experimental animals. The estrogenic activity of each diet was reevaluated by comparison with a calibration curve of 17 beta-estradiol. Almost all of the diets had estrogenic activity. The diets for rabbits and guinea pigs had the highest estrogenic activity compared to any other diets, including those for rats and mice. Estrogenic activity was found in dried skim milk, fishmeal, soybean meal, and alfalfa meal. In the NIH-07 diet opened for the ingredients, estrogenic activity was nearly all derived from the alfalfa meal. Multiple assays were performed to evaluate potential seasonal variations in the estrogenic potency in the raw materials of the rat and mouse diets. We found that the estrogenic activity in these raw materials changed throughout the year.  相似文献   
76.
Previous studies have shown the physiological significance of dietary conjugated linoleic acid (CLA) in various experimental animals and in human beings. One of the important problems to better elucidate is the difference between triglyceride (TG) and free (FFA) dietary CLA. Here, using splenocytes, this study assesses how TG- and FFA-CLA modulate immunoglobulin and various cytokine productions. In this study, C57BL/6N mice were fed an experimental diet containing 0% CLA, 0.1 or 1% FFA-CLA, or 0.1 or 1% TG-CLA for 3 weeks. The production of immunoglobulin tended to be up-regulated by 1% FFA-CLA. As a result of protein array analysis using the supernatant from splenocytes cultured with no CLA, 1% FFA-CLA, and TG-CLA, some cytokine production was shown to be remarkably regulated by dietary FFA- and TG-CLA. A total of 32 cytokines were examined, and 11-14 produced cytokines that were 2-fold up-regulated as compared with control for FFA- or TG-CLA, respectively. Especially, the production of IL-9 and MCP-5 and other cytokines was remarkably up-regulated by both FFA- and TG-CLA. In addition, seven cytokines were 2-fold down-regulated by TG-CLA. These data show that there is a slight but significant difference between the functionalities of FFA- and TG-CLA.  相似文献   
77.
The liver is an important organ that contributes to milk production in dairy cows. The aim of this study was to examine whether liver conditions affect the characteristics of blood plasma and follicular fluid (FF) and whether supplementing in vitro maturation medium with FF from either cows with damaged livers (DL) or those with healthy livers (HL) affects oocyte developmental competence. Biochemical characteristics of FF were significantly correlated with those in plasma. As such, the characteristics of both plasma and FF were similarly affected by liver conditions in that the concentrations of total protein and inorganic phosphorus were higher for the DL cow group than for the HL cow group, whereas the concentrations of albumin, lactate dehydrogenase and calcium were lower for DL cows than for HL cows. In addition, supplementing the medium with DL‐FF retarded the progression of the nuclear maturation of oocytes collected from the HL cows. On culturing oocytes in maturation medium containing HL‐FF, DL‐FF or foetal calf serum, the highest developmental rate to the blastocyst stage was observed in the HL‐FF group, while the lowest developmental ratio was observed in the DL‐FF group. The growth factor array of the FFs revealed that 10 growth factors were significantly downregulated in the DL‐FF compared with those in HL‐FF. In conclusion, the characteristics of plasma and FF are affected by liver conditions in a similar way. Concentrations of several growth factors were low in DL‐FF, as was the ability of DL‐FF to support oocyte maturation compared with that of HL‐FF.  相似文献   
78.
Unreduced gamete formation is significant in the evolutionary development of complex polyploidy series found in wild strawberry, genus Fragaria (Rosaceae). Also, it is important for genetics and breeding in strawberry plants to elucidate the mechanism of unreduced gamete formation. The objective of this study was to search for ploidy anomalies resulting from artificial diploid × octoploid crosses, and examine the mechanism through which these unreduced gametes were produced. Five everbearing cultivars of Fragaria vesca L. diploid (2n = 2x = 14) were crossed with pollen from six June-bearing cultivars of Fragaria × ananassa Duch., octoploid (2n = 8x = 56). A total of 3000 mature seeds, 100 from each of the 30 parental combinations were sown at 23 °C/20 °C (day/night) under artificial lighting with a 16 h day. The seedlings were transplanted to pots and grown in a greenhouse. Reproductive and morphological observations, flow cytometry analyses, chromosome counts and DNA analyses using CAPS markers were performed to identify the genetic background of the offspring. Most of the seed (79%) did not germinate or died soon after germination. Of the seedlings produced, 7% seemed to be pure F. vesca based on morphological characteristics, flow cytometry analyses and chromosome counts; 14% were pentaploids (2n = 5x = 35), 0.1% were hexaploids (2n = 6x = 42), and 0.03% (one individual) was aneuploid (2n = 8x + 2 = 58). Electrophoresis banding patterns obtained by CAPS marker analysis were heterozygotic in the 8x pollen parent but homozygotic in the aneuploid progeny. Judging from the chromosome counts and the CAPS marker analysis, the aneuploid was the result of a homozygous unreduced pollen grain (8x) crossed with an incomplete chromosome compliment from the egg. Because of the homozygosity, the unreduced male gamete must have been derived from second division restitution (SDR) in the octoploid pollen parent.  相似文献   
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