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41.
The ochratoxin A (OTA) content of urine samples from 88 healthy humans living at five settlements in three counties of Hungary was determined by immunoaffinity column cleanup and high-performance liquid chromatography (HPLC). OTA was detected in 61% of the samples in an average concentration of 0.013 ng/ml (range: 0.006-0.065 ng/ml). OTA concentrations measured in urine samples from men and women were not significantly different. The OTA concentration of samples from Heves county was significantly (t-test; p < 0.003) higher than that of samples from Hajdú-Bihar and Somogy counties. The regional differences in OTA concentration of urine samples indicate regional differences in the OTA exposure of the human population. Further studies are necessary to determine the cause of the regional differences in the OTA intake. The studies allow us to conclude that the OTA intake of the majority of the Hungarian population is low (< 1 ng/kg of body weight per day) but a certain part of the rural population may take up higher levels of OTA.  相似文献   
42.
In this work the antiviral activity of 20 dehydroepiandrosterone (DHEA) analogs with different substituents at positions C-3, C-15, C-16 and C-17 were evaluated against vesicular stomatitis virus (VSV) in Vero cell cultures. The selectivity indexes (SI) obtained with DHEA and epiandrosterone (EA) were 50 and 72.6, respectively. The work showed that the compounds 21-norpregna-5,17(20)-dien-3β,16α-diyl-diacetate, 17,17-ethylendioxyandrostan-5,15-dien-3β-ol and 3β-hydroxypregn-17(20)-en-16-one had higher SI values than ribavirin, which was used as a reference drug. The antiviral mode of action of DHEA was also investigated against VSV replication in Vero cells, and time of addition experiments showed that DHEA mainly affected a late event in the virus growth cycle. Analysis of RNA and protein synthesis indicated that DHEA adversely affected positive strand RNA synthesis and viral mature particle formation.  相似文献   
43.
The objective of this study was to determine the associations among Haemophilus parasuis, Mycoplasma hyorhinis, and porcine reproductive and respiratory syndrome (PRRS) virus (EU-field strain) infections in 95 pigs with polyserositis. A significant association between H. parasuis and M. hyorhinis was identified. H. parasuis and M. hyorhinis were significantly more often detected in PRRS virus positive pigs.  相似文献   
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The medical records of 220 dogs with inflammatory/infectious diseases of the central nervous system (CNS) were retrospectively examined. The aims of the study were to determine if clinical and clinicopathologic data (not including biopsy or necropsy examination) could distinguish inflammatory CNS diseases from diseases of other types, and to search for criteria allowing differentiation of specific inflammatory diseases. The signalment, historical findings, extraneural and neurological signs, and the lesion site contributed marginally to a specific diagnosis. Multifocal signs were only noticed in one third of the dogs with inflammatory/infectious diseases. Particular neurological abnormalities were more frequent in certain diseases than in others (eg, myoclonus was frequent in dogs with distemper, but it was also found in those with other meningoencephalomyelitides). Hematologic findings contributed to the diagnosis in certain conditions (eg, canine distemper encephalitis, protozoal encephalomyelitis, steroid-responsive meningitis-arteritis). Cerebrospinal fluid examinations, including immunoglobulin G index and cytology were useful to separate meningoencephalomyelitides from the other CNS diseases and to distinguish certain conditions from others. In most cases a specific diagnosis depended on a combination of clinical signs and ancillary diagnostic aids. Still, a specific diagnosis remained very difficult, if not impossible, in at least one third of the dogs.  相似文献   
46.
BACKGROUND: Inflammation of the central nervous system (CNS) is a frequent condition in cats but etiology often remains unsolved. Routine cerebrospinal fluid (CSF) analysis can be extended through the calculation of the albumin quotient (Q(alb)), a marker of the integrity of the blood-brain barrier (BBB), and IgG index, an estimate of intrathecal IgG synthesis. OBJECTIVES: The purpose of this study was to validate nephelometric methods for CSF protein analysis, and to use the Q(alb) and IgG index to discriminate blood- and brain-derived immunoglobulin fractions in cats with feline infectious peritonitis (FIP). METHODS: Cats presented to our clinic between 2001 and 2005 were included in the study based on clinical and laboratory data and histopathologic findings at necropsy. Cats were grouped as having nonneurologic disease (controls; n=37), brain tumors (n=8), FIP involving the CNS (n=12), and extraneural FIP (n=12). CSF-total protein (TP) was measured and albumin and IgG concentrations were measured in paired CSF/serum samples; Q(alb) and IgG index were calculated. Intraassay and interassay precision of the nephelometric assays were determined using pooled samples. RESULTS: Coefficients of variation for the nephelometric assays ranged from 2.7% to 7.2%. In control cats, CSF-TP concentration ranged from 0.06 to 0.36 g/L, Q(alb) ranged from 0.6 to 5.7 x 10(-3), and IgG index ranged from 0.3 to 0.6. Q(alb) and IgG index were significantly higher in cats with brain tumors and cats with CNS-FIP compared with other groups. Compared with control cats, pleocytosis was evident in 8 of 12 (67%) cats and CSF-TP was increased in 3 of 12 (25%) cats with CNS-FIP. CONCLUSION: Nephelometry is a reliable method for measurement of CSF protein, albumin, and IgG in cats. The Q(alb) and IgG index did not identify a CSF protein pattern specific for BBB dysfunction or intrathecal IgG synthesis in cats with CNS-FIP.  相似文献   
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A 4-y-old, female mixed-breed dog was presented to the Ontario Veterinary College for further evaluation of multiple pulmonary and hepatic masses, intrathoracic lymphadenitis, and recent development of a pyogranulomatous pleural effusion. Along with other comprehensive tests, a thoracic lymph node biopsy was performed, and Mycobacterium tuberculosis complex infection was confirmed by real-time PCR. The dog’s condition declined post-operatively, and euthanasia was elected. Postmortem examination confirmed severe granulomatous pneumonia, hepatitis, intrathoracic and intraabdominal lymphadenitis, omentitis, and nephritis. Line-probe assays performed on samples collected postmortem confirmed the species as M. tuberculosis. 24-loci MIRU-VNTR genotyping, spoligotyping, and whole-genome sequencing revealed relations to known human isolates, but no epidemiologic link to these cases was investigated. Given the concern for potential human exposure during this animal’s disease course, a public health investigation was initiated; 45 individuals were tested for M. tuberculosis exposure, and no subsequent human infections related to this animal were identified. Our case highlights the need for more readily available, minimally invasive testing for the diagnosis of canine mycobacteriosis, and highlights the ability of canid species to act as potential contributors to the epidemiology of M. tuberculosis infections.  相似文献   
49.
意大利冷冻精液质量的官方监控   总被引:1,自引:0,他引:1  
1991年1月15日,意大利政府公布了动物生产法,即法律30(legge30),全面介绍了动物生殖细胞生产中心应具备的条件、建立养殖场的要求和动物繁殖的规章制度。1994年1月13日,意大利农业部依据法律30发布了第172号部长令,详细说明了自然交配、人工授精和胚胎移植的规章制度。部长令规定,意大利任何冻精生产中心(简称中心)生产的冻精或从国外引入的冻精,必须至少取出精液生产批次10%的样品,进行官方检测。司拜伦谨尼研究所(简称研究所)是意大利农业部委托的唯一的执行机构,检测的最后结果是:比较研究所…  相似文献   
50.
Buffalo milk represents an indispensable source of nourishment in many parts of the world and it is the second most consumed milk worldwide. Buffalo milk is actually used for the production of many dairy products such as pasteurized or concentrated milk, butter, yogurt, ice‐cream, dehydrated milk products and cheeses. Due to its high nutritional value and the presence of natural bioactive substances, buffalo milk can also provide health benefits to consumers. In Italy, buffalo milk is used mainly for cheese making, mozzarella PDO (Protected Designation of Origin), which is a highly valued dairy product. This 3‐year study, carried out between 2011 and 2013, was aimed at evaluating the quality of bulk Italian Mediterranean buffalo milk by monitoring physico‐chemical parameters, somatic cell and total bacterial counts. A total of 51 samples of bulk milk were collected from one herd throughout the monitored period. Analysis of variance, carried out to test month, season and year main effects, highlighted remarkable seasonal effects for fat, protein and lactose content, as well as for predicted mozzarella cheese yield, and somatic cell counts. The calculation of simple correlations allowed the identification of positive correlations between estimated cheese yield and fat and protein content.  相似文献   
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