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161.
Recent evidence strongly suggests that oxidative stress due to redox imbalance is highly associated with metabolic syndrome. The objective of this study was to evaluate the effect of the supplementation of longan flower water extract (LFWE), which showed powerful antioxidative activity in vitro, on markers of metabolic syndrome in a fructose-fed rat model. Male Sprague-Dawley rats were randomly divided into four groups: group C, fed with standard Purina chow; group F, fed with high-fructose diet (HF) alone; group L, fed with HF plus LFWE 125 mg/kg bw per day by gavage; and group H, fed HF plus LFWE 250 mg/kg bw per day by gavage. The dietary manipulation lasted for 14 weeks. Results of our study showed that rats fed with HF resulted in oxidative stress and affected the antioxidant status including plasma thiobarbituric acid and liver antioxidant enzyme activity. Treatment with LFWE significantly augmented the antioxidant system. HF was able to cause insulin resistance and elevation of the blood pressure. The supplementation of LFWE ameliorated insulin resistance by enhancing the expression of insulin signaling pathway related proteins, including insulin receptor substrate-1 and glucose transporter 4. LFWE supplementation was also found to decrease systolic blood pressure. These findings indicate that longan flower water extract may improve the symptoms of metabolic syndrome in fructose-fed rats.  相似文献   
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Fallow deer were immobilised using a combination of xylazine and ketamine. Adult males (n = 10) and adult females (n = 10) received 4 mg/kg of each drug intramuscularly. Juveniles (n = 11) received 2 mg/kg of each drug, intravenously. Times to recumbency were as follows: adult males 4.9 +/- 2.9 min, adult females 4.1 +/- 1.9 min, juveniles 2.3 +/- 1.1 min. After 30 min each deer received 0.2 mg/kg of yohimbine, or an equal volume of sterile diluent intravenously. Yohimbine substantially reduced the recovery times of treated deer. Adults males were releasable 7.2 +/- 4.3 min after yohimbine administration, whereas control males were not releasable until 165 +/- 18 min. Treated adult females were releasable after 6.6 +/- 4.3 min, while control females were not releasable until 84 +/- 29 min. Juveniles were releasable 2.1 +/- 0.8 min after administration of yohimbine but control juveniles were not releasable until 62 +/- 16 min. Xylazine/ketamine administration produced statistically significant changes in packed cell volume, total plasma protein, albumin, sodium, glucose, creatine phosphokinase and inorganic phosphate values after 30 min. Yohimbine administration had no effect on these changes.  相似文献   
164.
This study presents evidence for the dehydrogenation of lindane by a hepatic microsomal mixed-function oxidase system. Preliminary investigation established that the incubation of lindane with rat liver homogenates produces a chlorinated, nonpolar compound identified as hexachlorocyclohexene. Differential centrifugation resulted in the sedimentation of most of the dehydrogenase activity in the microsomal fraction. Optimum in vitro assay conditions were established and it was found that the dehydrogenase system required molecular oxygen and reduced pyridine nucleotide coenzyme for maximum activity. Inhibition by SKF 525-A and CO suggested that the enzyme was cytochrome P-450 dependent. Lack of inhibition by cyanide indicated that the cytochrome b5 desaturase system was probably not involved. Pretreatment of rats with DDT, which stimulates lindane metabolism, also induced significantly higher dehydrogenase activity. Both the in vivo and in vitro metabolism of hexachlorocyclohexene produced previously identified lindane metabolites. The existence of a cytochrome P-450 dependent mixed-function oxidase which catalyzes the dehydrogenation of lindane has not previously been reported and may be of importance in the metabolism of other xenobiotics.  相似文献   
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166.
Earlier studies have shown that the B haplotype has a significant influence on the protective efficacy of vaccines against Marek's disease (MD) and that the level of protection varies dependent on the serotype of MD virus (MDV) used in the vaccine. To determine if the protective glycoprotein gene gB is a basis for this association, we compared recombinant fowlpox virus (rFPV) containing a single gB gene from three serotypes of MDV. The rFPV were used to vaccinate 15.B congenic lines. Nonvaccinated chickens from all three haplotypes had 84%-97% MD after challenge. The rFPV containing gB1 provides better protection than rFPV containing gB2 or gB3 in all three B genotypes. Moreover, the gB proteins were critical, since the B*21/*21 chickens had better protection than chickens with B*13/*13 or B*5/*5 using rFPV with gB1, gB2, or gB3. A newly described combined rFPV/gB1gEgIUL32 + HVT vaccine was analyzed in chickens of lines 15 x 7 (B*2/*15) and N (B*21/*21) challenged with two vv+ strains of MDV. There were line differences in protection by the vaccines and line N had better protection with the rFPV/gB1gEgIUL32 + HVT vaccines (92%-100%) following either MDV challenge, but protection was significantly lower in 15 X 7 chickens (35%) when compared with the vaccine CVI988/Rispens (94%) and 301B1 + HVT (65%). Another experiment used four lines of chickens receiving the new rFPV + HVT vaccine or CVI988/Rispens and challenge with 648A MDV. The CVI 988/Rispens generally provided better protection in lines P and 15 X 7 and in one replicate with line TK. The combined rFPV/gB1gEgIUL32 + HVT vaccines protected line N chickens (90%) better than did CVI988/Rispens (73%). These data indicate that rFPV + HVT vaccines may provide protection against MD that is equivalent to or superior to CVI988/ Rispens in some chicken strains. It is not clear whether the rFPV/gB1gEgIUL32 + HVT vaccine will offer high levels of protection to commercial strains, but this vaccine, when used in line N chickens, may be a useful model to study interactions between vaccines and chicken genotypes and may thereby improve future MD vaccines.  相似文献   
167.
A continuous glucose monitoring system (CGMS) was evaluated in 14 cats with naturally occurring diabetes mellitus. The device measures interstitial fluid glucose continuously, by means of a sensor placed in the subcutaneous tissue. All cats tolerated the device well and a trace was obtained on 15/16 occasions. There was good correlation between the CGMS values and blood glucose concentration measured using a glucometer (r=0.932, P<0.01). Limitations to the use of the CGMS are its working glucose range of 2.2-22.2 mmol/l (40-400 mg/dl) and the need for calibration with a blood glucose measurement at least every 12 h. When compared to a traditional blood glucose curve, the CGMS is minimally invasive, reduces the number of venepunctures necessary to assess the kinetics of insulin therapy in a patient and provides a truly continuous glucose curve.  相似文献   
168.
Objective: To report intussusception as a complication of methiocarb toxicity in dogs and discuss possible risk factors. Series summary: Intestinal intussusception was diagnosed from 24 hours to 18 days following symptomatic treatment of methiocarb toxicity in three dogs. All cases had persistent clinical signs of methiocarb toxicity despite initial treatment and attempts to eliminate residual toxin. Cases 1 and 3 recovered uneventfully following supportive care, enterectomy of the affected bowel and end‐to‐end anastamosis. All dogs were <8 months of age. New information provided: Details of three cases of methiocarb toxicity that later developed intussusception and possible risk factors in these cases.  相似文献   
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170.
No knowledge regarding the peripartum changes in mammary secretions in the jenny are presently available in literature. In the mare, instead, several studies report the role of these changes as indicators of foetal readiness for birth and impending parturition. This experiment was designed to determine calcium, sodium, potassium concentrations, and the value of sodium/potassium ratio in mammary fluids during prepartum in the jenny. Samples were daily collected by hand milking, after mammary gland size increased noticeably, from 17 Martina Franca jennies. Prepartum mammary secretions were analysed every other day between day 10 and day 2 antepartum, and then once a day from the day before to the day of parturition. Calcium concentration showed a significant increase between day 10 and day 6 antepartum and then between day 6 and days 4 and 2. Afterwards, another statistical significant increase was observed at parturition. Sodium concentration significantly decreased from day 10 to day 2 prepartum. Potassium concentration significantly increased between day 10 and day 8 before parturition, then showed a further increase at day 4, followed by none significant changes until foaling. All jennies showed a reversal in sodium/potassium ratio between 2 days antepartum and the day before. In conclusion, the evaluation of mammary fluid calcium concentrations and the reversal of sodium/potassium ratio could be used as good indicators of foetal maturity in the jenny. As far as the prediction of parturition is concerned, the reversal of sodium/potassium ratio is the best parameter, since it was detected 48–24 h before parturition in all considered animals.  相似文献   
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