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Lindane analogs, in which one or two chlorine atoms are replaced by various substituents, exhibit convulsive and lethal effects on Periplaneta americana (L.). Some analogs are as active as lindane. These effects are well related to the neuroexcitatory action which produces after-discharges in the central nervous system. Carbamate insecticides have potent convulsive and lethal effects on P. americana, which are also related to after-discharges produced in nerve cords. Convulsion caused by lindane analogs and carbamates is solely attributable to their neuroexcitatory effects on the nervous system, in spite of the difference in their ultimate modes of action.  相似文献   
3.
 Reactive oxygen species (ROS) generation was examined in the interaction of Alternaria alternata Japanese pear pathotype and host plants using three methods: nitro blue tetrazolium (NBT) method for microscopic detection of O2 , diaminobenzidine (DAB) methods for microscopic detection of H2O2, and cerium chloride methods for ultrastructural detection of H2O2. ROS generation was detected by NBT and DAB methods at appressoria on leaves of susceptible cultivars and heat-shocked leaves of resistant cultivars but not in leaves of resistant cultivars. Ultrastructural detection by the cerium chloride method identified ROS generation at cell walls of appressoria and penetration pegs in susceptible, resistant leaves and heat-shocked leaves. These differences in the ultrastructural and microscopic data in resistant areas were due to the restriction of ROS generation in limited areas, the side facing the plant surface, of appressoria and penetration pegs. Therefore, ROS generation was apparently induced regardless of the resistance or susceptibility of the cultivar with the difference being in the volumes generated. After evaluating the pathological role of ROS generation in fungal structures, such generation was found to be associated with early penetration of cell walls in pear plants. Additionally, ROS generation in plants was also found in degrading pectin layers near infected hyphae and in plasma membrane modification sites in susceptible leaves but not in resistant leaves. ROS generation in susceptible leaves might be accompanied with plasma membrane damage, although the role of ROS generation in the pectin layers is not clear. ROS generation in both fungal and plant cells during their interaction was likely associated with the expression of susceptibility. Received: June 3, 2002 / Accepted: July 31, 2002  相似文献   
4.
Supplementation with both cystine and glutamic acid increases the synthesis of glutathione (GSH), which has a marked effect on immune cell function, as compared with supplementation with either amino acid alone in human macrophages in vitro. As dietary glutamic acid is metabolized during intestinal transport, oral administration of L-theanine (gamma-glutamylethylamide), which is metabolized to glutamic acid mainly in the liver, may act as a glutamic acid donor in vivo. The present study was performed to investigate the effects of oral administration of L-cystine and/or L-theanine on GSH levels and immune responses. Co-administration of L-cystine (200 mg/kg) and L-theanine (80 mg/kg) for 11 days before immunization significantly increased the levels of total GSH in the liver 6 hr after immunization as compared with the levels in control mice. To examine the effects of administration of L-cystine and/or L-theanine on the balance of T helper (Th) 1/Th2 cell responses, the serum ratios of the Th1 cytokine, interferon (IFN)-gamma, and the Th2 cytokine, interleukin IL-10, were investigated. At 24 hr after immunization, co-administration significantly increased the IL-10/IFN-gamma ratio compared with the ratios of the control and single-administration mice. Furthermore, co-administration before primary immunization significantly enhanced serum antigen-specific IgG levels. Taken together, these findings suggest that co-administration of L-cystine and L-theanine enhances antigen-specific IgG production partly through augmentation of GSH levels and Th2-mediated responses.  相似文献   
5.
Bacterial tests were used to assess bacterial contamination of game meat from Japanese wild boars. The bacterial contamination of wild boar meat was less than that of domestic pork, as determined by aerobic plate counts (APC) and coliform counts. None of the meat examined in this study was contaminated by Salmonella or E. coli O-157. To detect adulteration by domestic pig meat or European wild boar meat, 46 samples of game meat sold as Japanese wild boar were examined genetically. A total of 17 samples showed genetic haplotypes of European and Asian domestic pigs in the D-loop of mitochondrial DNA (mtDNA), and 16 samples showed nuclear glucosephosphate isomerase-processed pseudogene (GPIP) genotypes of European domestic pigs. The European GPIP genotypes of these samples were confirmed by PCR-RFLP analysis. These results indicate that some game meat sold as Japanese wild boar is adulterated by cross-breeding between pigs and wild boars or by contamination with meat from domestic pigs or European wild boars.  相似文献   
6.
The ability to stimulate N-acetylglucosamine (GluNAc) incorporation in-vitro of a number of N-tert-butyl-N,N′-dibenzoylhydrazines having various substituents on both phenyl rings was measured in cultured integument excised from the rice stem borer (Chilo suppressalis Walker). The relationship between in-vitro and larvicidal potency was approximately linear. The substituent effects on variations in the potency were similar between in-vitro and larvicidal activities. An inhibitor of oxidative detoxication, piperonyl butoxide, had no synergistic effects on the in-vitro potency. The ability of some dibenzoylhydrazines to inhibit GluNAc incorporation at exposure periods longer than the optimum for stimulation was also measured in a similar cultured integument system. The relationship between the inhibitory and stimulatory potency indices was linear, indicating that the larvicidal activity of dibenzoylhydrazines is closely related to its ability to stimulate as well as to inhibit GluNAc incorporation into the larval cuticle.  相似文献   
7.
OBJECTIVE: To evaluate the effects of a high-protein diet versus dietary supplementation with ammonium chloride (NH4Cl) on struvite crystal formation in the urine of clinically normal cats by measuring the urine concentration of hydrochloric acid (HCl)-insoluble sediment, urine pH, struvite activity product (SAP), number of struvite crystals in urine, and urine volume. ANIMALS: 23 healthy adult cats. PROCEDURE: Urine was fractionated by centrifugation with subsequent extraction of the sediment with 1 N HCl (study 1). Diets containing either 29% crude protein or 55% crude protein were fed to cats in a crossover trial of 3 weeks/period (study 2). Diets supplemented with either sodium chloride (NaCl) or NH4Cl were fed, by use of a 3 x 3 Latin-square design with 3 wk/period (study 3). In studies 2 and 3, urine samples were collected for the last 7 days of each period. RESULTS: The HCl-insoluble sediment contained Tamm-Horsfall glycoprotein (THP; study 1). The high-protein diet (study 2) and dietary supplementation with NH4Cl (study 3) resulted in a decrease in urine pH, SAP, and the number of struvite crystals in urine. However, the high-protein diet decreased urine concentrations of HCl-insoluble sediment containing THP (study 2), in contrast to the NH4Cl supplementation that increased urine volume without a significant effect on the urine concentration of the HCl-insoluble sediment (study 3). CONCLUSIONS AND CLINICAL RELEVANCE: Our results indicate that compared with dietary supplementation with NH4Cl, the high-protein diet is preferable as a urine acidifier for the prevention of struvite crystal formation in clinically normal cats.  相似文献   
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9.
This work was designed to observe the dentine incremental lines of the sika deer (Cervus nippon) fawns and to investigate their periodicity using the chronological labeling method with fluorochromes. The incremental lines were observed in decalcified specimens stained by Bodian's silver technique, and the fluorescence-labeled lines were observed in undecalcified and ground specimens. In the silver stained specimens, there were two types of lines, deeply stained thick lines and faintly stained minute regular incremental lines. The intervals and staining intensities of the deeply stained thick lines were very similar to those of the fluorescence-labeled lines in the ground specimens obtained from the same tooth, and hence, it appeared that the both lines were identical. The number of minute incremental lines between the deeply stained thick lines was the same as that of days between the time when each fluorescent labeling injection was made. Therefore, it seemed that each minute incremental line was formed each day. The possibility of age estimation in days using diurnal dentine increments was discussed.  相似文献   
10.
To evaluate the effectiveness of sodium bicarbonate (SB) in removing uranium and protecting animals from uranium toxicity, we intramuscularly administered 1 mg/kg of uranyl nitrate to 8-wk-old male SD rats, and 20 min after administration of uranyl nitrate, the animals were given a single oral administration of SB at 0.1, 0.3 or 1 g/kg. The SB treatment at a dose of 0.3 g/kg or more raised the pH of the rats’ urine until 4 h after treatment, and it significantly reduced the uranium amounts in the kidneys at 1 day after treatment. In another experiment, rats were intramuscularly administered 1 mg/kg of uranyl nitrate, and 20 min later, the animals were treated with sodium bicarbonate (0.1 or 1 g/kg). The rats were autopsied at 1, 3 and 7 days after uranium treatment. High-dose SB resulted in a significant increase in urinary uranium excretion in the first 24 h and a reduction of uranium deposition in the kidneys and femurs, and it also significantly suppressed uranium-induced renal toxicity, as shown by both histopathology and clinical chemistry at 3 days after uranium treatment. Low-dose SB did not show such marked effects. Our findings demonstrated that the uranium decorporation effect of sodium bicarbonate was observed at the dosage showing urine alkalinization in rats and that decorporation effect of sodium bicarbonate might be beneficial if it is administered immediately after incorporation of soluble uranium.  相似文献   
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