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41.
A Jack Russell terrier with a history of progressive exercise intolerance was examined at the age of four months and again 10 months later. Clinical examination revealed a stunted, thin dog with a stilted gait. The dog had raised lactate levels before and after feeding and a raised lactate/pyruvate ratio after feeding, indicating a metabolic abnormality. Histochemical evaluation of muscle biopsies revealed subsarcolemmal accumulation of oxidative activity when stained with nicotinamide adenine dinucleotide tetrazolium reductase and ragged red fibres when stained with modified Gomori trichrome; all fibre types were involved. Ultrastructural examination of the muscle confirmed the presence of subsarcolemmal accumulations of mitochondria. Histochemical staining for the activity of enzymes of the Krebs cycle, oxidative phosphorylation and other metabolic cytosolic enzymes failed to demonstrate an abnormality. In view of the clinical picture and the biochemical and histological findings, a tentative diagnosis of mitochondrial myopathy was made. The difficulties associated with diagnosing mitochondrial disorders are discussed.  相似文献   
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An angiosarcoma involving the right frontal and maxillary sinuses in a nine-year-old Thoroughbred mare was studied post mortem by light and electron microscopy. Important diagnostic features included malignant endothelial cells lining ill-defined vascular spaces, supported by other vasoformative elements. Rhabdomyoblasts were also found. The tumour is apparently rarely seen in the nasal passages of the horse.  相似文献   
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Avian influenza outbreaks have occurred during winter months, and effective disinfection of poultry premises at freezing temperatures is needed. The commercial disinfectants Virkon and Accel, supplemented with an antifreeze agent [propylene glycol (PG), methanol (MeOH), or calcium chloride (CaCl2)], were evaluated for their effectiveness in killing avian influenza virus (AIV) at −20°C or 21°C. An AIV suspension was applied to stainless steel disks, air-dried, and covered with a disinfectant or antifreeze agent for 5 to 30 min. Virkon (2%) and Accel (6.25%) with 30% PG, 20% MeOH, or 20% CaCl2 inactivated 6 log10 AIV within 5 min at −20°C and 21°C. At these temperatures PG and MeOH alone did not kill AIV, but the 20% CaCl2 solution alone inactivated 5 log10 AIV within 10 min. The results suggested that CaCl2 is potentially useful to enhance the effectiveness of disinfection of poultry facilities after outbreaks of AIV infection in warm and cold seasons.  相似文献   
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In this study, we measured the effect of ginsenosides on glucose uptake using the Caco-2 cell system. At submicromolar concentrations, these compounds exhibited marked effects on the rate of glucose transport across the differentiated Caco-2 cell monolayer. Compound K (CK), the main intestinal bacterial metabolite of the protopanaxadiol ginsenosides, significantly enhanced the steady-state glucose transport rate to about 50% of the control sample rate (from 1.54 +/- 0.09 to 2.25 +/- 0.15 nmol/min). Conversely, the protopanaxatriol ginsenoside Rg1 inhibited glucose transport to about 70% of the original rate (from 1.54 +/- 0.09 to 1.02 +/- 0.05 nmol/min). Consistent with the effect on glucose uptake rate, CK and Rg1 conferred a significant and paralleled alteration on both the protein and mRNA expression levels of the Na+/glucose cotransporter 1 (SGLT1) gene. Unlike SGLT1, there is no significant alteration on the protein or mRNA levels of GLUTs in CK- or Rg1-treated cells. Taken together, our results demonstrate that ginsenosides CK and Rg1 elicited potent enhancing and suppressing effects, respectively, on glucose uptake across human intestinal Caco-2 monolayer through modulation of SGLT1 expression.  相似文献   
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OBJECTIVE: Throughout the world, the proportion of the male population aged 65 years and older is increasing. Yet, we have limited information regarding diet quality and predictors of diet quality in this segment of the population. The objectives of the current analyses are to describe the diet quality of a cohort of men >65 years of age, and identify lifestyle factors associated with poor diet quality. METHODS: We present a cross-sectional analysis of the diet quality of 5928 men, aged 65-100 years, who are participants in the Osteoporotic Fractures in Men (MrOS) cohort study. Dietary intake was determined using a modified Block 98 food-frequency questionnaire. Diet quality was calculated using the previously validated Diet Quality Index-Revised (DQI-R). Univariate and multivariate modelling was used to estimate the variance in diet quality predicted by a number of sociodemographic factors, including age, race/ethnicity, body mass index (BMI), marital status, education, smoking status, physical activity, self-perceived health and nutritional supplement use. RESULTS: Overall, we found that in this geographically diverse group of older men, diet quality was low, with a mean modified DQI-R for the entire study population of 62.5 (standard deviation 13.1) out of an ideal of 100. Further, younger age, very low total calorie intake (< or = 1187 kcal day- 1), higher BMI, residence in a North or Southeast community, being of African-American or Hispanic race, being less educated, not using dietary supplements and smoking were each significant independent predictors of a poorer diet. CONCLUSION: These data may prove useful in both understanding the dietary intake of older US men as it relates to published dietary guidelines, and for targeting future dietary intervention programmes.  相似文献   
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Lee YA  Chan CW 《Phytopathology》2007,97(2):195-201
ABSTRACT Burkholderia cenocepacia (genomovar III of B. cepacia complex), the causal agent of banana finger-tip rot, is a common plant-associated bacterium but also an important opportunistic pathogen of humans. To better understand the nature of B. cenocepacia from banana, the genetic variation among B. cenocepacia isolates from various banana-growing regions in southern Taiwan was examined. Forty-four serial isolates recovered from diseased banana stigmata from three banana-growing regions during the periods ranging from 2002 to 2004 were investigated. All B. cenocepacia isolates picked from quinate-yeast extract tetracycline-polymyxin semiselective medium could cause onion maceration and were polymerase chain reaction (PCR) positive for bcscV, which is a type III secretion gene present in all members of the B. cepacia complex except B. cepacia (formerly genomovar I). Genetic diversity was assessed using recA PCR restriction fragment length polymorphism, recA nucleotide sequence analysis, and pulsed-field gel electrophoresis assays. The assays revealed the genetic variability among the isolates and also allowed us to trace the relationship among isolates. The isolates all were assigned to genomovar III and consisted of two groups, A and B, which corresponded to recA lineage IIIA and IIIB. The group B strains were separated into B1 and B2 subgroups and the B1 strains were further divided into distinct lineages. The B1 strains were the most frequently detected and occurred in all regions tested. There was no significant difference between strains from each subgroup in the virulence on banana fingers of cv. Cavendish. PCR assays were further used to determine whether B. cenocepacia from banana contained the cable pilus subunit gene (cblA), IS1356, and B. cepacia epidemic strain marker (BCESM), which are DNA markers associated with epidemic B. cepacia clinic strains. The results indicated that cblA and IS1356 were absent but the BCESM was found in all isolates. The present study revealed that banana is a natural reservoir of genetically diversified B. cenocepacia strains.  相似文献   
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Brucellosis is a zoonotic disease that is transmitted from animals to humans, and the development of a rapid, accurate, and widely available identification method is essential for diagnosing this disease. In this study, we developed a new Brucella canis species-specific (BcSS) PCR assay and evaluated its specificity and sensitivity. A specific PCR primer set was designed based on the BCAN_B0548-0549 region in chromosome II of B. canis. The PCR detection for B. canis included amplification of a 300-bp product that is, not found on other Brucella species or, genetically or serologically related bacteria. The detection limit of BcSS-PCR assay was 6 pg/μl by DNA dilution, or 3 × 103 colony-forming units (CFU) in the buffy coats separated from whole blood experimentally inoculated with B. canis. Using the buffy coat in this PCR assay resulted in approximately 100-times higher sensitivity for B. canis as compared to detect directly from whole blood. This is the first report of a species-specific PCR assay to detect B. canis, and the new assay will provide a valuable tool for the diagnosis of B. canis infection.  相似文献   
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