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1.
Canine cationic trypsin was purified by salting-out, gel filtration and affinity chromatography. Purity was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weight was ca. 28 kDa by SDS-PAGE.

Thirty hybridomas were obtained which produced mAb to canine cationic trypsin by the cell fusion technique. Twenty-two of these recognized cationic trypsin only, while eight hybridomas recognized both cationic and anionic trypsin. Several of the anti-canine cationic trypsin mAb were purified by salting-out and DEAE ion-change chromatography using ascites fluid of immunized BALB/c mice. The mAb proved to have very high specificity to canine cationic trypsin as shown by immunoblotting and it may be possible to use them to develop clinical assays.  相似文献   

2.
Bentazon, 3-isopropyl-2,1,3-benzothiadiazin-4-one-2,2-dioxide is effective for weed control in flooded rice fields not only as a foliar treatment but also as a flooded-water or paddy soil treatment. Generally the herbicidal effect develops slowly only after translocation of the herbicide has occurred, but when the weeds contacted directly with relatively high concentrations of the herbicide, the effects appear rather rapid.The slow herbicidal effect appears to be an important mode of action of bentazon applied practically on weeds under flooded rice field conditions. The slow effect may be caused by inhibition of photosynthesis as supported by the following experimental results: a) Bentazon inhibited the Hill reaction in isolated chloroplasts; b) bentazon rapidly inhibited photosynthetic CO2 fixation in susceptible Cyperus serotinus and other plants; c) the herbicidal effects appeared much slower when bentazon was applied as a flooded-water treatment; d) bentazon injury was prevented by endogenous or exogenously supplied carbohydrates.  相似文献   
3.
A class III chitinase gene (CHI2) is induced in cucumber plants (Cucumis sativa L.) in response to infection by pathogenic microorganisms. Infection of Botrytis cinerea, causal agent of gray mold disease on cucumber, also induces CHI2 expression. To investigate whether CHI2 is involved in resistance to gray mold disease, transgenic cucumber plants were produced to overexpress the CHI2 gene. One line was analyzed in detail in terms of disease resistance. The transgenic cucumber plant (CC2) constitutively expressed CHI2 and reduced the symptoms of B. cinerea for 4 days after inoculation compared with nontransgenic plants. However, this inhibitory effect was not absolute, and CC2 eventually developed serious disease symptoms. Chitinase activity of the crude extract from CC2 leaves was higher than that from nontransgenic plants. A high-molecular-weight fraction containing CHI2 from CC2 leaves had fungistatic activity against B. cinerea. Interestingly, the low-molecular-weight fraction from CC2 leaves with CHI2 removed also had fungistatic activity against B. cinerea. Not only the introduced chitinase activity but also the endogenous defense reactions activated by overexpression of CHI2 may be involved in the enhanced gray mold disease resistance in CC2.  相似文献   
4.
Paddy and Water Environment - In Japan, since ancient times, numerous small- to medium-size agricultural ponds have been constructed to irrigate paddy rice fields. Economic growth and urbanization...  相似文献   
5.
The aim of the present study was to examine whether cumulus and fibroblast cell nuclear-transferred oocytes, which have high and low potential to develop into normal calves, respectively, are different in terms of in their patterns of timing of first cleavage and in their relationships between timing of first cleavage and in vitro developmental potential. The timing of first cleavage was similar in both types of nuclear-transferred and in vitro fertilized oocytes. More than 86% of the oocytes cleaved within 24 h after activation or in vitro fertilization; these oocytes contributed to more than 98% of the total number of blastocysts in all three groups. The potential of oocytes that cleaved at different intervals to develop into blastocysts differed among the groups. The developmental potential of the cumulus cell nuclear-transferred oocytes and in vitro fertilized oocytes decreased with the increase in time required for cleavage. Fibroblast cell nuclear-transferred oocytes that cleaved at 20 h, an intermediate cleaving time, had higher potential to develop into blastocysts. The results of the present study suggest that the type of donor nucleus used for nuclear transfer affects the timing of first cleavage.  相似文献   
6.
Feces were collected from two female and one male Siberian tigers, Panthera tigris altaica. Steroid hormones were extracted from lyophilized feces and quantified by enzyme immunoassay. The fecal contents of estradiol-17beta (E(2)) and testosterone in the females and male, respectively, changed markedly throughout the year. The fecal E(2) contents of females Nos. 179 and 238 increased at 26.4 +/- 8.0 and 28.0 +/- 14.2 day intervals, respectively. However, the fecal contents of progesterone (P(4)) in the female kept alone did not change. In contrast, the other female, which was kept with a male, had increased fecal P(4) contents after copulation. The fecal progesterone levels of the pregnant female remained high during her 106-day pregnancy.  相似文献   
7.
Abstract:   Heterosigma akashiwo virus (HaV) is a large icosahedral virus (∼0.2 μm) harboring a double-stranded DNA (dsDNA) genome (∼294 kbp). The virus is the only member of the genus Raphidovirus in the family Phycodnaviridae. Since its first discovery, a number of ecologic, physiologic and genetic studies about HaV have been conducted; especially, the relationship between H. akashiwo and HaV in nature was studied and viral infection is now regarded as a significant factor influencing the dynamics and termination of H. akashiwo blooms. HaV infection has considerable impacts on H. akashiwo populations in both aspects of fluctuation in biomass (quantity) and changes in clonal composition (quality). Partial sequencing of the HaV genome revealed that a number of genes showed considerable similarity to those of other protist-infecting viruses; still, the phylogenetic position of HaV suggested a number of enigmas in host–virus coevolution. Here are summarized the ecology, physiology and genetics of HaV especially from the viewpoint of the host–virus relationship.  相似文献   
8.
9.
Oat globulin was modified by a calcium-independent microbial transglutaminase (TG). The TG-polymerized protein had higher solubility than the control at acidic pH and had improved water- and fat-binding properties. Incubation of 10% (w/v) oat globulin dispersions in the presence of TG at 37 degrees C led to the formation of a well-developed viscoelastic gel network with a microstructure characterized by thick strands and large clusters. The TG-induced gels had higher modulus values, lower loss tangent values, and lower frequency dependency than the heat-induced gels. The TG-induced gel system has the characteristics of classical polymer gel with permanent "chemical" cross-links, whereas the heat-denatured system has the characteristics of a temporary "physical" gel with breakable cross-links. Fourier transform infrared spectroscopy showed marked shift and intensity changes in several major bands, suggesting pronounced changes in protein conformation during TG-induced gelation. Aggregation of protein molecules was also indicated by the progressive increases in two infrared bands (1679-1682 and 1622-1625 cm(-)(1)) associated with the formation of intermolecular beta-sheets and strands. Results suggest that new food polymers with unique functionality can be produced from oat globulin treated with TG and that elastic gels can be formed near neutral pH, instead of the alkaline pH required for thermally induced oat globulin gels.  相似文献   
10.
A novel fibrinolytic enzyme was purified from fermented shrimp paste, a popular seasoning used in Asian countries. The enzyme is a monomer with an apparent molecular weight of 18 kDa, and it is composed primarily of beta-sheet and random coils. The N-terminal amino acid sequence was determined to be DPYEEPGPCENLQVA. It is a neutral protease with an optimal activity from pH 3 to 7. No inhibition was observed with PMSF, Pepstatin A, E64, and 1,10-phenanthroline, but the enzyme was slightly inhibited by EDTA and Cu(2+). It was relatively specific to fibrin or fibrinogen as a protein substrate, yet it hydrolyzed none of the plasma proteins in the studies. In vitro, the enzyme was resistant to pepsin and trypsin digestion. It also had an anticoagulant activity measured with activated partial thrombin time and prothrombin time tests. The novel fibrinolytic enzyme derived from traditional Asian foods is useful for thrombolytic therapy. In addition, this enzyme has a significant potential for food fortification and nutraceutical applications, such that its use could effectively prevent cardiovascular diseases.  相似文献   
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