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1.
ABSTRACT: To clarify the quantitative changes in the transport of orally intubated protein into the blood circulation as macromolecules in development, immunoglobulin Y (IgY) extracted from chicken eggs was administered orally to juvenile Japanese eel, Anguilla japonica . For the first experiment, which was performed before the commencement of artificial feeding, the oral delivery of 2.0 μg/0.1 g bodyweight of IgY resulted in a rapid increase in plasma IgY to a maximum of 2.30 μg/mL. However, the transport of IgY into the blood decreased significantly in the experiments that followed, which were performed after 12, 25 and 42 days. During this period, bodyweight increased approximately by a factor of eight, and rapid growth of the stomach was observed histologically. Possible contributions for the development of the alimentary canal to the diminishment of intestinal protein assimilation are discussed.  相似文献   
2.
A diagnosis of toxic necrotizing cholangiohepatitis was made in approximately 35% of a flock of 23,000 commercial broiler chickens. Affected chickens were small, and had discrete green foci throughout the liver. Seven to twelve days prior to shipping the flock to slaughter, premixes containing oxytetracycline, monensin, and 3-nitro-4-hydroxyphenylarsonic acid had been added to the ration because the birds had wet droppings and were growing slowly. The 3-nitro-4-hydroxyphenylarsonic acid had been inadvertently incorporated at ten times the recommended level. Liver and kidney of affected birds had elevated levels of total arsenic, and special strains demonstrated arsenic in necrotic foci in liver. Histologically there was marked dilation of intrahepatic bile ducts, and patchy necrosis and hyperplasia of the bile duct epithelium. Damage to bile ducts may have been a toxic manifestation of altered metabolism and excretion of the three drugs being fed to birds suffering from intercurrent diarrhea and/or undefined interactions among the drugs.  相似文献   
3.
Porcine circovirus type 2 (PCV2) shedding patterns were investigated by polymerase chain reaction (PCR) for the detection of PCV2 DNA, and the diagnostic suitability of a sample for the PCR was examined by using different types of samples. In the experimental infection, sixteen pigs were inoculated intranasally with PCV2. The samples, including oropharyngeal and nasal swabs, feces, whole blood and serum became positive for PCV2 DNA by PCR immediately after the inoculation, and almost all samples remained positive during the observation period, post-inoculation-day 70. Field samples were collected from 313 pigs in five different age groups. The overall percentages of positive samples in the whole blood, nasal swabs, and feces detected by PCR were 30.4%, 19.2%, and 20.4%, respectively. The frequency of positive samples increased after the nursery stages and reached a peak in the 3 to 4-month-old pigs. These results indicate that PCV2 infection may occur after weaning, that PCV2 DNA may be present in whole blood for a long period after infection, and that whole blood and serum are the most suitable sample types for the PCR analysis of PCV2.  相似文献   
4.
5.
Neural cadherin: role in selective cell-cell adhesion   总被引:20,自引:0,他引:20  
Cadherins are a family of Ca2+-dependent intercellular adhesion molecules. Complementary DNAs encoding mouse neural cadherin (N-cadherin) were cloned, and the cell binding specificity of this molecule was examined. Mouse N-cadherin shows 92 percent similarity in amino acid sequence to the chicken homolog, while it shows 49 percent and 43 percent similarity to epithelial cadherin and to placental cadherin of the same species, respectively. In cell binding assays, mouse N-cadherin did not cross-react with other mouse cadherins, but it did cross-react with chicken N-cadherin. The results indicate that each cadherin type confers distinct adhesive specificities on different cells, and also that the specificity of N-cadherin is conserved between mammalian and avian cells.  相似文献   
6.
We performed a comparative experiment to investigate: (1) how the ubiquitous soil bacterium Bacillus subtilis weathers granite; and (2) which granite-forming minerals weather more rapidly via biological processes. Batch system experiments (granite specimen in a 500 ml solution including NaCl, glucose, yeast extract and bacteria B. subtilis at 27 °C) were carried out for 30 days. Granite surfaces were observed by SEM before and after the experiment. B. subtilis had a strong influence on granite weathering by forming pits. There were 2.4 times as many pits and micropores were 2.3 times wider in granite exposed to B. subtilis when compared with bacteria-free samples. B. subtilis appear to preferentially select an optimum place to adhere to the mineral and dissolve essential elements from the mineral to live. Plagioclase was more vulnerable to bacterial weathering than biotite among the granite composing minerals.  相似文献   
7.
Dual infection of pigs with swine influenza virus (SIV) and Mycoplasma hyopneumoniae was carried out to compare the clinical and pathological effects of dual infection in caesarian derived and colostrums deprived (CDCD) pigs, with that of a single infection with M. hyopneumoniae. In Experiment 1, 40-day-old CDCD pigs were inoculated only with SIV (A/Sw/Hok/2/81, H1N1). The virus was isolated from nasal swabs for 5-6 days. None of these pigs showed clinical signs of infection throughout the experimental period. These results suggested that this strain can infect pigs but is only slightly pathogenic when it is inoculated singly to a CDCD pig. In Experiment 2, 60-day-old CDCD pigs were inoculated with M. hyopneumoniae and then were inoculated with SIV (A/Sw/Hok/2/81) at 1 week (MHYO-7d-SIV-7d group) or 3 weeks (MHYO-21d-SIV-7d group) after M. hyopneumoniae inoculation. Macroscopically, dark red-to-purple lung lesions were observed in all of pigs at 14 or 28 days post-inoculation. Percentages of dark red-to-purple lung lesions in dual infection groups (MHYO-7d-SIV-7d group: 18.7 +/- 4.2%, MHYO-21d-SIV-7d group: 23.0 +/- 8.0%) were significantly (P < 0.05) increased compared to those of each control group in which pigs were inoculated only with M. hyopneumoniae (MHYO-14d group: 4.7 +/- 2.9%, MHYO-28 group: 3.3 +/- 2.4%). Microscopically, bronchial epithelial lesions (epithelial disruption, degeneration, hyperplasia and formation of microabscess) were frequently observed in dark red-to-purple lung lesions of only the dual infection groups. These results demonstrate that the lung lesion of pigs inoculated with M. hyopneumoniae and SIV is more severe than that of pigs inoculated only with M. hyopneumoniae.  相似文献   
8.
  • 1. SECORE (SExual COral REproduction) Project is an initiative of public aquariums and research institutions to produce and exchange sexual coral recruits for the sustainable management of ex situ populations. Here we present the results of the initial three years (2002–2004).
  • 2. Primary polyps (n=501) of corals (Acropora tenuis, Agaricia humilis, Favia fragum) were transported from Rotterdam Zoo to Cologne, Burgers', Hagenbeck and London Zoos, where development of juveniles was monitored for 10 months. All polyps were produced at Rotterdam Zoo from laboratory colonies (A. humilis, F. fragum), and from larvae generated from field collected gametes at Akajima, Okinawa, Japan (A. tenuis). Additionally, planulae of A. tenuis (n=1440) were transported from Rotterdam Zoo to Burgers' Zoo and to London Zoo to obtain primary polyps.
  • 3. Larval settlement (A. tenuis) was observed to be 3.00 ± 2.57% (mean ± SD; n=1480) in 2002 and 17.36 ± 6.01% (mean ± SD; n=1480) in 2003, significantly lower compared to settlement at Rotterdam Zoo (57.84 ± 11.01% in 2003; mean ± SD, n=1480). High post‐transport survival rates of 95.18 ± 4.86% (mean ± SD; n=501) were observed in primary polyps of all species.
  • 4. Juvenile survival (t=10 months; A. tenuis: 18.4–86.2%; A. humilis: 0–19.7%; F. fragum: 13.3–72.7%) differed significantly between institutions. Mean colony sizes (measured 10 months after transportation) were, in all cases, similar or higher to those reported from literature.
  • 5. The results demonstrate the potential of this method to serve as an economical and sustainable alternative to existing mostly exploitative techniques for aquarium stocking. The use of sexual recruits provides an effective and low cost alternative, which is, in principle, applicable to all coral species.
  • 6. The project was extended from 9 to 28 institutions across Europe, the USA and Japan in 2004.
Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
9.
The radical-scavenging antioxidants play an important role against oxidative stress in the defense system in vivo. The beneficial effects of antioxidants contained in foods and beverages have been well-accepted, and their antioxidant capacity has been assessed by various methods. In the present study, a simple method is proposed in which the total radical scavenging capacity is assessed from the bleaching of pyranine and pyrogallol red induced by free radicals generated from azo initiator. The total content of antioxidants contained in red wine, green tea, and cassis drink and their reactivities toward peroxyl radicals were measured from the lag phase and rate of bleaching using pyranine and pyrogallol red as a probe, respectively. It was found that this method to follow the bleaching of two probes by visible light spectrophotometer is convenient and applicable for assessment of total radical scavenging capacity of both content and activity of the antioxidants contained in beverages.  相似文献   
10.
The role of radical scavenging antioxidants against oxidative stress has received much attention, and the antioxidant capacity has been assessed by various methods. Among them, a method that measures the effect of antioxidant on decay of the probe is one of the most widely used methods. The present study was performed to compare the two methods to assess the antioxidant capacity, one to follow the decay of the probe and the other to measure lipid peroxidation products in human plasma. It was shown that the method following probe decay was suitable for assessment of radical scavenging capacity of antioxidant, but not for the capacity to inhibit lipid peroxidation in plasma. This is true whether a hydrophilic or lipophilic probe is used. Such different results arise from the fact that the efficacy of inhibition of lipid peroxidation by antioxidants depends on the fate of antioxidant-derived radical and interaction between antioxidants as well as the capacity of free radical scavenging. Thus, the capacity of antioxidants for inhibition of lipid peroxidation should be assessed from the effect on the extent of oxidation, not from the effect on probe decay.  相似文献   
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