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41.
Juvenile Pacific bluefin tuna (Thunnus orientalis; PBT) often experience high mortality during ship transportation. This study investigated whether the addition of colours or patterns to the walls of tanks affected survival rate. In the first experiment, three colours and lattice patterns were tested: dark blue single‐colour, red single‐colour, and red–blue lattice pattern. Fish in all tanks exhibited abnormal behaviours when sunlight entered the tanks between 0800 and 1000 hours, but mortality only increased in the single‐coloured tanks as a result of collision with the tank walls. In the second experiment, four colours and patterns were tested: dark blue single‐colour, red–blue lattice pattern, red–blue lattice pattern with shade sheet and red–green lattice pattern with shade sheet. Again, we visually observed that fish in all treatment groups exhibited abnormal behaviour when sunlight entered the tanks, but there were no collision deaths in the lattice‐patterned tanks and survival in this group was significantly higher than in the single‐coloured tanks. Thus, the use of a high‐contrast colour pattern can prevent mass death of juvenile PBT during ship transportation.  相似文献   
42.
To investigate the factors affecting the surface-check variation in boxed-heart square timber of sugi (Cryptomeria japonica), surface checks formed by the conventional kiln drying were compared for two stem heights of five cultivars with different wood properties. The total length and average length of the surface checks were greater at the upper part of the stems for all the cultivars. This might be caused by more sapwood at the upper part of the stem, and large drying stresses between the outer sapwood and the inner heartwood. The cultivars, in which tangential shrinkage was large owing to small microfibril angle, formed longer surface checks and smaller bow. There was a positive relationship between surface-check length and tangential shrinkage. The heartwood percentage and tangential shrinkage were thought to be important factors affecting the surface-check variation in sugi boxed-heart square timber.  相似文献   
43.
Mycobacterium tuberculosis complex, which includes Mycobacterium bovis, infrequently causes severe or lethal disease in captive wildlife populations. A dead coati from a wildlife triage center showing pulmonary lesions compatible with tuberculosis had raised suspicion of a potential disease caused by mycobacteria species and was further investigated. Four native coatis (Nasua nasua) with suspected mycobacterial infection were sedated, and bronchoalveolar lavages and tuberculin skin tests (TSTs) were performed. All animals tested positive upon TST. Mycobacterial culturing, Ziehl-Neelsen staining, and genetic testing were performed on postmortem samples and the etiologic agent was identified as M. bovis. Molecular genetic identification using a polymerase chain reaction panel was crucial to achieving a definitive diagnosis.  相似文献   
44.
Four acetophenone glycosides were isolated from the butanol-soluble fraction of thyme extracts. Their structures were determined by spectral methods (MS, NMR, and 2D-NMR). Among them, two new compounds, 4-hydroxyacetophenone 4-O-[5-O-(3, 5-dimethoxy-4-hydroxybenzoyl)-beta-D-apiofuranosyl]-(1-->2)-beta-D -gl ucopyranoside (1) and 4-hydroxyacetophenone 4-O-[5-O-(4-hydroxybenzoyl)-beta-D-apiofuranosyl]-(1-->2)-beta-D-+ ++gluc opyranoside (2), were determined. Compound 1 showed weak cytotoxicity, inhibiting DNA synthesis of human leukemia cells.  相似文献   
45.
The spatial distributions and feeding habits of Pacific cod ( Gadus macrocephalus ) larvae, and the spatial distributions of copepod nauplii and copepodites, their main prey, were examined in Mutsu Bay from February to March during 1989–92. Yolk-sac larvae were caught at 30–45 m depth at the bay mouth. Larvae without yolk were collected at 8–45 m depth at the bay mouth and the inner part of the bay, and large larvae were chiefly found in the bay. This geographical pattern in larval size may have been because of transport to the inner part of Mutsu Bay by the Tsugaru Warm Current. The dominant taxa of copepod nauplii and copepodites in the diet and the environment changed each year. Larvae fed mainly on abundant taxa in the environment, suggesting that larvae are opportunistic feeders. Nauplii and copepodites were abundant in the bay, especially in 1992. Copepodites were slightly more abundant in the diet of cod larvae in 1992 than in 1991, but this difference was smaller than in the environment. In addition, larvae with empty digestive tracts were scarce in 1991 and 1992. Prey concentrations in the bay in 1991 and 1992 seem to have been high enough to sustain most Pacific cod larvae.  相似文献   
46.
To investigate the effects of rearing practices of commercial broiler chickens on the incidence of antimicrobial resistance in commensal Escherichia coli isolates, fecal E. coli isolates obtained in 4 farms were screened for anitimicrobial resistance. Ten E. coli isolates were recovered from each of the fecal samples collected from 10 birds in the farms at the ages of 2 days, 14-17 days, and 47-50 days. In 2 out of the 4 farms, no antimicrobials were used during the rearing period. In the other two farms, following collection of the fecal samples at 14 and 15 days of age, oxytetracycline (OTC), sulfadimethoxine (SDMX), and tylosin were given to birds on one farm and SDMX was used in the other. Isolates resistant to ampicillin and OTC that were obtained from an untreated flock at different sampling times were closely related to each other by pulsed-field gel electrophoresis patterns (PFGE) of XbaI-digested chromosomal DNA. PFGE analysis together with in vitro conjugation experiments suggested that diversity of resistance phenotypes within a clone may be resulted from the acquisition and loss of R-plasmids in an untreated and a treated flock. The numbers of resistance phenotypes observed among fecal isolates increased during the growth of the chickens in all the farms. The results in the present study suggest that persistence of commensal E. coli strains resistant to antimicrobials even in the absence of antimicrobial administration. It is also hypothesized that horizontal transmission of resistance determinants resulted in the emergence of different resistance phenotypes in those farms.  相似文献   
47.
Dilated cardiomyopathy is a severe pathology of the heart with poorly understood etiology. Disruption of the gene encoding the negative immunoregulatory receptor PD-1 in BALB/c mice, but not in BALB/c RAG-2-/- mice, caused dilated cardiomyopathy with severely impaired contraction and sudden death by congestive heart failure. Affected hearts showed diffuse deposition of immunoglobulin G (IgG) on the surface of cardiomyocytes. All of the affected PD-1-/- mice exhibited high-titer circulating IgG autoantibodies reactive to a 33-kilodalton protein expressed specifically on the surface of cardiomyocytes. These results indicate that PD-1 may be an important factor contributing to the prevention of autoimmune diseases.  相似文献   
48.
49.
Intercalated layered materials comprising an organic dye and inorganic MPS(3) [where M is either the manganese ion (Mn(2+)) or the cadmium ion (Cd(2+))] phases have been prepared. The intercalation process induces a spontaneous poling, giving rise to an efficiency of 750 times that of urea in second-harmonic generation for the cadmium derivative. In addition, the manganese derivative displays a permanent magnetization below 40 kelvin. Thus, these materials exhibit both a large optical nonlinearity and magnetic ordering.  相似文献   
50.
Among domestic animals, teat order is only observed in the pig. In order to achieve the healthy growth and weaning of piglets, it is important to elucidate if volume of colostrum secretion and immunoglobulin A (IgA) and IgG concentrations differ among the teats of a sow. Nine sows were used to evaluate the difference in colostrum secretion volume (CSV) and four of these sows were assessed for IgA and IgG concentrations from each teat. Samples were collected five times during 21 h following parturition. Teats were assigned anatomical locations of teat (1 to 7) from anterior to posterior. The CSV of anterior (locations 1 and 2) and middle teats (locations 3–5) was significantly higher than those of posterior teats (locations 6 and 7) throughout the experiment except for 18 h post‐parturition (P < 0.05). The CSV of the teats at location 1 was significantly higher at most collection times than those at locations 6 and 7. A positive correlation of CSV was observed with IgA and IgG concentrations from 12 h and 6 h post‐parturition, respectively (P < 0.05). The results suggest that anterior teats secrete greater volumes of colostrum and that these tend to contain higher IgA and IgG than posteriors teats.  相似文献   
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