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601.
In this study, we investigated diabetic stage dependent cyclooxygenase-2 (COX-2) immunoreactivity in the dentate gyrus in streptozotocin (STZ)-induced type 1 diabetic rats. The animals were sacrificed at 2, 3 and 4 weeks after STZ treatment. Blood glucose levels were increased after STZ treatment. COX-2 immunoreactivity in dentate gyrus was significantly increased in these regions 3 weeks after STZ treatment and restored to its basal level to 4 weeks after STZ treatment. In contrast, COX-2 immunoreactivity was not changed in CA3 region in all groups. These results suggest that STZ-induced type 1 diabetes transiently, but not permanently, decreased synaptic transmission and plasticity 3 weeks after STZ treatment in the dentate gyrus.  相似文献   
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604.
Treatment of pepper plants with the nonprotein amino acid, DL-ß-amino-n-butyric acid (BABA) induced resistance to subsequent infection byPhytophthora capsici. In contrast, theα-, andγ-isomers of aminobutyric acid were ineffective as inducers of resistance. A relatively high concentration of BABA at 1,000μg ml?1, which had no antifungal activityin vitro againstP. capsici, was required to induce resistance against Phytophthora blight with a foliar and stem spray, thus leading to complete control of the disease. About 1 day interval between BABA-treatment and challenge inoculation was sufficient to induce resistance in pepper plants. High inoculum levels ofP. capsici caused Phytophthora development slowly in pepper stems treated with BABA, especially at early plant growth stage, which suggests that the induced resistance in pepper plants may be more quantitative rather than qualitative. BABA applied to the root system also protected pepper stems fromP. capsici infection.  相似文献   
605.
Journal of Plant Diseases and Protection - Sixty-three isolates of Didymella rabiei collected from southern Alberta were analyzed for pathogenic variability using six differential chickpea...  相似文献   
606.
The pharmacokinetics and dosage regimen of norfloxacin-glycine acetate (NFLXGA) was investigated in pigs after a single intravenous (i.v.) or oral (p.o.) administration at a dosage of 7.2 mg/kg body weight. After both i.v. and p.o. administration, plasma drug concentrations were best fitted to an open two-compartment model with a rapid distribution phase. After i.v. administration of NFLXGA, the distribution (t1/2α) and elimination half-life (t1/2β) were 0.36 ± 0.07 h and 7.42 ± 3.55 h, respectively. The volume of distribution of NFLXGA at steady state (Vdss) was 4.66 ± 1.39 l/kg. After p.o. administration of NFLXGA, the maximal absorption concentration (Cmax) was 0.43 ± 0.06 µg/ml at 1.36 ± 0.39 h (Tmax). The mean absorption (t1/2ka) and elimination half-life (t1/2β) of NFLXGA were 0.78 ± 0.27 h and 7.13 ± 1.41 h, respectively. The mean systemic bioavailability (F) after p.o. administration was 31.10 ± 15.16%. We suggest that the optimal dosage calculated from the pharmacokinetic parameters is 5.01 mg/kg per day i.v. or 16.12 mg/kg per day p.o.  相似文献   
607.
Foliar pathogens attack alfalfa wherever the crop is grown, but their impact, especially on seed production, is poorly understood. In greenhouse trials, leaf spot injury caused by inoculation with various pathogens reduced the crude protein content of infected alfalfa leaves by 22% compared with a healthy control. There was a negative relationship between disease injury and the photosynthetic efficiency of alfalfa plants, as determined by measuring chlorophyll fluorescence in leaves from inoculated vs. non-inoculated seedlings. In field trials at two sites in Alberta from 2001 to 2003, inoculation with Phoma medicaginis increased disease incidence in four of six trials, Phoma sclerotioides increased incidence in four of five trials, and Leptosphaerulina trifolii and Stemphylium botryosum increased incidence in two of six trials. There was a trend for inoculation treatments to reduce seed yield, despite high levels of background infection by indigenous pathogens. The fungicides benomyl and propiconazole inhibited radial growth of Phoma spp. in vitro and reduced disease incidence in inoculated greenhouse experiments. In field trials, applications of benomyl and propiconazole reduced disease incidence, but did not always increase seed yield.  相似文献   
608.
A seven-year-old castrated male Yorkshire terrier dog was presented for a recurrent skin disease. Erythematous skin during the first visit progressed from multiple plaques to patch lesions and exudative erosion in the oral mucosa membrane. Biopsy samples were taken from erythematous skin and were diagnosed with epitheliotropic T cell cutaneous lymphoma by histopathology and immunochemical stain. In serum chemistry, the dog had a hypercalcemia (15.7 mg/dl) and mild increased alkaline phosphatase (417 U/l). Immunohistochemistry was performed to detect parathyroid hormone-related peptide (PTH-rP) in epitheliotropic cutaneous lymphoma tissues but the neoplastic cells were not labeled with anti-PTH-rP antibodies. The patient was treated with prednisolone and isotretinoin. However, the dog died unexpectedly.  相似文献   
609.
The hypoglycemic effects after oral administration of vanadium have been studied previously in many species such as rats, mice and even humans. However, there has been no prior report on the glucose lowering effect of vanadium on diabetic dogs. Therefore, the purpose of this study was to evaluate the hypoglycemic effects of oral vanadium on diabetic dogs. Diabetes mellitus in the dogs studied was induced by alloxan monohydrate intravenous injection. The dogs were divided into two groups, one was the diabetic control (DC) group (n = 4) and the other was the vanadium treated (DV) group (n = 6). Fresh water was supplied to the dogs in the DC group, but sodium metavanadate solution (0.1~0.2 mg/ml) was given to the dogs in DV group from one week after the alloxan injection. The fasting glucose levels, fructosamine and serum chemistry profiles were compared between the two groups weekly for three weeks. The fasting blood glucose levels in DV group were significantly lower than those in the DC group (p < 0.01). Fructosamine levels in the DV group were also lower than those in the DC group (p < 0.05). The serum chemistry profiles were not significantly different in comparisons between the two groups. However, the cholesterol levels were significantly lower in the DV group compared to the DC group (p < 0.05). Our findings showed that oral vanadium administration had a hypoglycemic effect on chemically induced diabetic dogs.  相似文献   
610.
柑桔黄龙病在福建省从1955年以后逐年增长。大家已一致认为这是一种病毒病害。现在就最近两年在漳州进行的嫁接接种、蚜虫传染和遮荫防病的试验报告如下。在1961年做了病梢皮贴接接种的两个试验。试验地周围400—500米内均无柑园,但接种树和对照树仅距离7—8米。在试验期间经常防治虫害并加强栽培管理。苗木是由病区南靖苗圃选择来的一年生健壮桶柑(即焦柑)嫁接苗(砧木是红桔)。三月间定植后一般生长良好。接种方法系  相似文献   
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