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101.
A bacterial leaf spot disease was observed on Hedera helix (English ivy) and H. canariensis (Algerian ivy) in Japan. The causal agent was identified as Xanthomonas campestris pv. hederae (Arnaud 1920) Dye 1978. Received 13 May 2002/ Accepted in revised form 3 July 2002  相似文献   
102.
Lactoferrin has several biological activities, including antitumor activities in some human and animal tumor cells. Clinical trials have been carried out in human medicine based on these effects. However, the antitumor effects of lactoferrin in veterinary medicine remain unknown. In this in vitro study, we demonstrated that co-incubation of canine mammary gland tumor cells (CIPp and CHMp) and bovine lactoferrin induced growth arrest of tumor cells. This growth arrest was associated with induction of G1 arrest. Furthermore, this effect was stronger in tumor cells than in normal cells. These findings demonstrate that bovine lactoferrin has anti-tumor activity in canine mammary tumors and has the potential for use in tumor-bearing dogs.  相似文献   
103.
Feline immunodeficiency virus (FIV) infection is characterized by chronic overactivation of immune and inflammatory system, resulting in anergic state and dysfunction of immune cells. Lactoferrin (LF), a glycoprotein present in exocrine secretions and neutrophils, plays an important role in host defense system. Our previous study showed that oral administration of bovine LF (bLF) suppressed oral inflammation, improved the clinical symptoms and decreased serum gamma-globulin as a marker of inflammation in FIV-infected cats with intractable stomatitis. The anti-inflammatory effect was partly involved in regulation of neutrophil function by bLF. In this study, to clarify the relationship between anti-inflammatory effects of bLF and peripheral blood mononuclear cells (PBMC), we examined the effect of bLF on proliferation, cell cycle progression and cytokine expression in mitogen-activated PBMC. MTT [3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl tetrazolium bromide] assay showed that bLF inhibited the concanavalin A (ConA)-induced cell proliferation in FIV-infected cats with the asymptomatic carrier and AIDS-related complex (ARC) phase. Bovine LF restored ConA-induced cell cycle progression and resulted in suppression of the induced apoptosis in feline PBMC. Real-time RT-PCR showed that bLF suppressed ConA-induced expression of interferon-gamma and interleukin-2 in cells of the ARC group regardless of the time of its addition to the medium. These results suggest the hypothesis that therapy with bLF may have the potential to improve and protect functions of overactivated lymphocytes by modulating the cell proliferation, cell cycle and cytokines expression in cats in terminal stage of FIV infection.  相似文献   
104.
Plant Foods for Human Nutrition - Amyloid β (Aβ) peptides produced from the amyloid precursor protein, a transmembrane protein, are neurotoxic and blocking the neurotoxicity may lead to...  相似文献   
105.
Five species ofOphiostoma, twoLeptographium species and aGraphium species were isolated from two morphologically and ecologically similar bark beetle species,Tomicus piniperda andT. minor, and their infested Japanese red pine (Pinus densiflora) in Yamanashi Prefecture, central Honshu, Japan. An underscribedOphiostoma species andO. minus were isolated mainly fromT. piniperda and its galleries.Ophiostoma canum which was found for the first time in Japan was mainly fromT. minor and its galleries. Specific relationships between the beetles and fungal species are suggested. Contribution No.140, Laboratory of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba. Part of this study was presented at 108th Annual meeting of Japanese Forestry Society, April 2, 1997, Fukuoka, Japan.  相似文献   
106.
Some physicochemical properties and molecular structures of starches from millet (Pennisetum typhoides, Doro and Gero) and sorghum (Sorghum bicolor, red and white) in Nigeria were examined. Starch granules of millet and sorghum were 3–14 μm and 4–26 μm in diameter, respectively. Millet cultivars had similar peak viscosities (204–205 RVU) on pasting, while sorghum showed similar minimum viscosities (155–156 RVU). The actual amylose content (%) calculated from iodine affinity (IA, g/100 g) was 20.1 and 21.4 for sorghum and 21.3 for millet. The IA of amylopectin was high (1.27–1.42) and its average chain lengths were 20–21 with β‐amylolysis limit of 56%. Amylopectins showed a polymodal molecular weight distribution on a molar basis. The distributions differed among the samples with a higher amount of larger molecules in Doro and red sorghum. Weight‐ and molar‐based distributions of debranched amylopectins on HPSEC were polymodal with weight‐based distribution showing presence of long chains. Peak DP values for A+B1 and B2+B3 chain fractions were 13–16 and 42–43, respectively. The (A+B1)/(B2+B3) ratio on molar basis (9.0–11.5) was similar to maize and rice amylopectins. Peak DP on molar‐based distribution for white sorghum and millet amyloses were similar (490–540) and the DPn range was narrow (1,060–1,300), but weight‐based distribution profiles differed. The average chain lengths were 260–270 with 3.9–4.8 chains per molecule.  相似文献   
107.
To elucidate the physiological role of calcitonin (CT) in stingrays (cartilaginous fish), an enzyme-linked immunosorbent assay (ELISA) system using a specific antibody against stingray CT has been developed. Synthetic stingray CT was subcutaneously injected into mice four times—once every 2 weeks—together with an adjuvant. We purified the IgG antibody fraction using the protein A affinity chromatography from collected antiserum. Evaluating the antibody titer, we found the antibody’s optimum dilution ratio to be 600 times. Competitive ELISA has been developed using the antibody diluted 600 times. Our antibody did not cross-react with teleost CTs and muscle extraction, but cross-reacted with stingray plasma and the extract of the ultimobranchial gland, the secretary organ of stingray CT. Using this ELISA, we measured the plasma CT level in stingrays and examined its correlation with several mineral concentrations. Plasma CT did not show significant correlation to calcium, magnesium, inorganic phosphorus, sodium, chlorine, or urea, although there was a correlation among the factors involved in osmoregulation, such as sodium, chlorine, and urea. On the other hand, plasma CT was significantly correlated to body weight and length. Furthermore, there was a significant correlation between plasma CT and gonad weight. Since plasma CT was correlated with the weight of liver, which is involved in the synthesis of egg yolk protein, we examined the influence of 17β-estradiol (E2) on CT secretion. After E2 injection, the plasma CT level increased significantly. This is the first study to demonstrate that E2 induced plasma CT secretion in cartilaginous fish.  相似文献   
108.
Expressed sequence tag (EST) analyses were performed with the aim of identifying enzyme genes in the liver of the Bleeker’s squid Loligo bleekeri. Of the 768 ESTs identified and sequenced, 669 were grouped into 324 clusters. Of these clusters, 123 comprising 245 ESTs were found to be homologous to genes reported to date. Among these, 43 clusters were annotated as enzymes according to the Enzyme Commission (EC) numbering system. Two EC groups, oxidoreductases and hydrolases, possessed a large number of ESTs. A cluster homologous to the glutathione peroxidase, an enzyme in the oxidoreductase group, contained 16 ESTs, which accounted for 2.4% of the total ESTs sequenced. There are three serine proteases, three cathepsins, two triacylgricerol lipases, and two chitinases among the clusters homologous to the enzymes in the hydrolase group. Since the squid liver functions in the digestive process, these enzymes would be involved in food digestion. Our data provide information on the various types of enzymes expressed in the squid liver and may provide a useful basis for further characterization of these enzymes.  相似文献   
109.
Larvae of jack mackerel Trachurus japonicus were sampled in seven depth layers (0–10 m, 10–20 m, 20–30 m, 30–40 m, 40–50 m, 50–70 m, and 70–100 m), with a closing-type frame net, on 26th–27th February, 2003, at Sta. V (27°50′N, 126°00′E) continental shelf edge in the southern part of East China Sea, to examine their vertical distribution. Most of the larvae (>90%) occurred in the upper 50 m layer during both day and night. In the daytime, larvae of length from 3.0 mm to 4.5 mm were most abundant in the 10–20 m layer, those from 5.0 to 6.0 mm were most abundant in the 20–30 m layer, those from 6.0 to 8.0 mm occurred at greater depth, in the 30–40 m layer, and those more than 9.0 mm were found in the 0–10 m layer and performed ontogenetic vertical migrations. Larvae from 6 mm to 8 mm length performed diurnal vertical migration, for the percentage (16.7%) of larval number in the 0–20 m layer in the daytime increased to 42.1% at night and the percentage (78.1%) in the 20–50 m layer in the daytime decreased to 49.0% at night.  相似文献   
110.
Sikimi plant (also known as Japanese star anise), Illicium anisatium, is toxic to mammals. Extracts of Sikimi were studied for their insecticidal activity against the larvae of mosquito, Culex quinquefasciatus, and for their mechanism of action on ion channels. Crude methanol extract and its ethyl acetate-soluble fractions were insecticidally active, with EC50 values of 63·0 μg ml-1 and 43·7 μg ml-1, respectively. The ethyl acetate-soluble fraction was perfused through the bathing solution and the current induced by a brief (10 ms) application of GABA by pressure ejection through pipette electrode was recorded by the whole-cell patch clamp technique. The extract suppressed GABA-induced currents irreversibly with an EC50 value of 0·42 μg ml-1. The time constant of current fitted to the single exponential function was shortened by the ethyl acetate-soluble fraction at concentrations ranging from 0·1 μg ml-1 to 10 μg ml-1 in a concentration-dependent manner. It was concluded that Sikimi extracts decreased the affinity of GABA for its binding site on the GABA receptor, thereby suppressing GABA-induced currents. © 1998 SCI  相似文献   
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