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1.
The northeastern region of India constitutes one of the biodi-versity hotspots of the world. The ethnic groups inhabiting this region practice their distinctive traditional knowledge systems using biod...  相似文献   
2.
Several neurodegenerative diseases such as Alzeimer's and Parkinson's as well as septic shock and inflammation involve formation of reactive oxygen and nitrogen species that include peroxynitrite (PON). PON can also react with endogenous antioxidants. Therefore, dietary supplementation with antioxidants may help in these diseases. An exogenous antioxidant, vanillin (4-hydroxy-3-methoxybenzaldehyde), used widely as a food flavoring agent, was evaluated for its ability to scavenge PON and inhibit PON-mediated reactions. Nitration of tyrosine by PON was assessed by high-performance liquid chromatography (HPLC). This reaction was inhibited by vanillin. The oxidation of dihydrorhodamine 123 to fluorescent rhodamine 123 was also inhibited by vanillin. The kinetics of reaction between PON and vanillin was studied by stopped-flow technique. The products of this reaction were analyzed by HPLC, and hydroxyvanillin was identified as one of the five products with absorption at 350 nm. These data demonstrate that vanillin effectively scavenges PON in cell-free systems.  相似文献   
3.
Ellagic acid, a plant-derived polyphenol, inhibits gamma-radiation (hydroxyl radical) induced lipid peroxidation in rat liver microsomes in a dose- and concentration-dependent manner. Its antioxidant capacity has been estimated using the 1,1-diphenyl-2-picrylhydrazyl radical assay. To understand the actual mechanisms involved in antioxidant activity and the free radical scavenging ability,a nanosecond pulse radiolysis technique has been employed. The rate constants for the reactions of several reactive oxygen species and reactive nitrogen species such as hydroxyl, peroxyl, and nitrogen dioxide radicals have been found to be in the range of 10(6)-10(9) M(-1) s(-1). The ellagic acid radicals have been characterized by the absorption spectra and decay kinetics. Studies on the reactions of ellagic acid with the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) radical and the radicals of ellagic acid with ascorbate have been used to estimate its one-electron reduction potential. Ellagic acid has also been found to be a good scavenger of peroxynitrite. Using stopped-flow reaction analyzer with absorption detection, the rate constant for this reaction has been determined to be 3.7 x 10(3) M(-1) s (-1). The electron spin resonance spectra of the oxidized ellagic acid radicals have been recorded by horseradish peroxidase and hydrogen peroxide method.  相似文献   
4.
A 5-year-old, spayed female cat was referred because of a mass in the cranial mediastinum noted on thoracic radiographs. A thymoma was diagnosed following ultrasound and biopsy of the mass. Treatment was initiated with coarse-fraction radiation therapy using external-beam therapy (four fractions of 5 Gy). The mass responded, but granulocytopenia developed. Bone marrow examination showed a myeloid to erythroid ratio of approximately 1:1, with a left shift within the myeloid line. These findings, as well as the lack of toxic changes within the peripheral blood neutrophils, suggested immune-mediated destruction of peripheral granulocytes. Immune suppression with prednisone and cyclosporine was instituted. After 7 weeks, the neutrophil count returned to normal. The tumor was removed, and cyclosporine was reduced and eventually discontinued 3 weeks postsurgery.  相似文献   
5.
Charcoal rot caused byMacrophomina phaseolina (Tassi) Goid. damages stalk tissue and weakens stalk strength, leading to lodging of crop and loss in grain yield in sorghum. In an attempt to understand the pathogenicity byM. phaseolina in relation to stalk characters and plant outputs, the effects of morphological (stalk-thickness), anatomical (bundle-number, bundle-density, and vascular tissue) and physiological characters (water and soluble sugar content) of the stalks of winter sorghum genotypes on charcoal rot development were analyzed. Bundle-number and stalk-thickness had a significant influence on internal spread of charcoal rot. A thicker stalk facilitated the spread of lesions more than did a thinner one. A stalk with densely packed vascular bundles inhibited lesion advancement. Field studies with 24 winter sorghum genotypes demonstrated that most of the parameters that could improve grain and stover yield also increased the length of charcoal rot lesions. Lesion development in stalks showed a high degree of association with grain yield (R2=0.51) and 100-grain weight (R2=0.42). The rate of symptom development in stalks differed during dough and maturity stages. It was concluded that anatomical characters of sorghum stalk, especially bundle-number, along with yield parameters played an important role in determining the extent of stalk damage by charcoal rot in winter sorghum. http://www.phytoparasitica.org posting March 25, 2008.  相似文献   
6.
The objective of this study was to determine theeffects of country liquor Toddy and its equivalentquantity of ethanol on lipid metabolism duringgestation in rats. Female rats weighing an average of125 g were exposed to Toddy (24.5 ml/body weight/day)and ethanol (0.52 ml/kg body weight/day) for 15 daysbefore conception and throughout gestation. On the19th day of gestation, altered liver function andhyperlipidemia was seen in both the treated groups.Altered liver function was evidenced by the increasedactivity of alcohol dehydrogenase, aldehydedehydrogenase, glutamic oxaloacetic transaminase oraspartate amino transferase (GOT), glutamic pyruvictransaminase or alanine amino transferase (GPT) andgamma glutamyl transpeptidase (GGT). Hyperlipidemiawas caused by increased biosynthesis and decreaseddegradation of lipids. The incorporation of 14Cacetate in lipids and activities of HMG CoA reductaseand lipogenic enzymes were elevated and activity ofLPL and bile acids contents were decreased. Toddytreated rats were more severely affected than thosereceiving an equivalent quantity of ethanol. Toddyseemed to potentiate the toxicity induced by alcoholindicating the role of the nonethanolic portion.Hepatic functions were also affected.  相似文献   
7.
The objective of this study was to determine the effects of an alcoholic beverage (Toddy) and the equivalent quantity of ethanol on carbohydrate metabolism in utero. Female rats were exposed to Toddy from coconut palm (24.5 ml/kg body weight/day) and ethanol (0.52 ml/kg body weight/day) for 15 days before conception and throughout gestation. On the 19th day of gestation, hypoglycemia was seen in both the treated groups, but it was more in the Toddy-treated group. Synthesis of glycogen was elevated on exposure to ethanol/Toddy but its degradation was enhanced only in alcohol-exposed rats. Key enzymes of citric acid cycle and gluconeogenesis were inhibited on administration of both alcohol and Toddy. Activity of glycolytic enzymes were increased. Toddy seemed to potentiate the toxicity induced by alcohol, indicating the additive effects of congeners.  相似文献   
8.
Insecticidal seed treatment is an alternative method to spray and granular applications. It can protect the crop right from germination to reproductive stage. Recurrent use of chemical insecticides destabilizes the ecosystem and enhances the development of resistance in pest population. Use of biopesticides like neem oil (NO) is a promising one in this situation. Two field experiments were conducted to test the efficacy of NO as a seed dresser (20 ml kg−1) and the effect was compared with systemic chemical insecticides imidacloprid (7 g kg−1) and carbosulfan (7 g kg−1) and Pseudomonas fluorescens (10 g kg−1). Field studies revealed that the neem oil 60EC (C) (NO 60EC (C)) recorded minimum population of sucking pests Leafhopper—Amrasca biguttula biguttula Ishida and Aphids—Aphis gossypii Glover (Homoptera: Cicadellidae and Aphididae), i.e., below the ETL (2 number per leaf) up to 45 days after sowing and provided better yield compared to control. Although the systemic chemical insecticide imidacloprid performed better by recording 11,280 and 11,580 kg ha−1 of marketable fruit yield, NO 60EC (C) also recorded about twofold increase in marketable fruit yield 11,000 and 10,620 kg ha−1, respectively, in 2001 and 2002 experiments. Results of this study suggest that NO could be used as a potential seed dresser for managing sucking pests in okra.  相似文献   
9.
Approximately 0.2% (n=4397) of the bovids (cattle and buffalo) in Sri Lanka were sampled, from June 1992 using a multi-stage sampling procedure. Serum antibodies for the rinderpest virus were detected using the competitive enzyme-linked immunosorbent assay. The age, the agroclimatic zone, the management system practiced in the farms, and the vaccination history of the sampled bovids were studied as potential risk factors for being seropositive.

The prevalence of rinderpest antibodies in non-vaccinated bovids was 3.5% (n=4101). The prevalence was higher in the dry zone (9%; where the outbreak emerged in 1987), compared to bovids in the other zones (1%). Seropositive bovids over three years of age were approximately at fourfold higher chances of being seropositive compared to those that were ≤3 years old. The higher prevalence in older animals is probably due to exposure to the virus during the 1987 epidemic. Bovids from the dry zone (annual rainfall 20 to 35 inches) were at higher odds of being seropositive even after controlling for the possible effects of age, agroclimatic zone, management system and vaccination. The fact that 62% of bovids from the dry zone in this study were reared under extensive management system (free grazing) which allow unrestricted contact between animals, may be the reason for the above finding. A relatively poor response to vaccination observed in vaccinated bovids (seroprevalence=12%; n=296) could be attributed to difficulties in maintaining the vaccine at recommended temperatures in the field. This is the first island-wide study on seroprevalence of rinderpest in Sri Lanka.  相似文献   

10.
OBJECTIVE: To evaluate the suitability of etorphine with acepromazine for producing prolonged neuroleptanalgesia in wild Asian elephants. ANIMALS: Ten adult wild elephants (four males, six females), free-roaming in the jungles of the north-western province of Sri Lanka. MATERIALS AND METHODS: Ten wild elephants were tranquilized for attachment of radio transmitter collars from September to November 1997, using Large-Animal Immobilon (C-Vet Veterinary Products, Leyland, UK), which is a combination of etorphine (2.45 mg mL(-1)) and acepromazine (10 mg mL(-1)). This was injected using projectile syringes fired from a Cap-Chur gun (Palmer Chemical Co. Inc., Atlanta, USA). A volume of 3.3 (2.5-4.5) mL Immobilon (6.12-11.02 mg of etorphine and 25-45 mg acepromazine) was injected intramuscularly after body mass estimation of individual elephants. RESULTS: The body condition of all darted elephants was good, and the mean (minimum-maximum) shoulder height was 225 (180-310) cm. The average approximate distance to elephants at firing was 26 (15-50) m. The average time to recumbency after injection was 18 (15-45) minutes. Nine out of 10 elephants remained in lateral recumbency (and did not require additional dosing) for a period of 42 (28-61) minutes. The respiratory and heart rates during anaesthesia were 7 (4-10) breaths and 52 (40-60) beats minute(-1), respectively. An equal volume (8.15-14.67 mg) of diprenorphine hydrochloride (Revivon, 3.26 mg mL(-1) diprenorphine; C-Veterinary Products, Leyland, UK) was given intravenously when the procedure was completed. Recovery (return to standing position) occurred in 6 (2-12) minutes after diprenorphine injection. Immediately afterwards, all elephants slowly retreated into the jungle without complications. Continuous radio tracking of the animals involved in this study indicated no post-operative mortality for several months after restraint. CONCLUSIONS/CLINICAL RELEVANCE: Etorphine-acepromazine combinations can be used safely in healthy wild Asian elephants for periods of restraint lasting up to 1 hour.  相似文献   
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