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31.
Chronic exposure to trace levels of waste anesthetic gases has been linked to higher incidences of neurologic and reproductive dysfunction, hepatic and renal toxicity, and neoplasia in health care professionals. We have shown that low levels of isoflurane emissions are likely in conventional laboratory animal treatment rooms during the use of standard anesthesia delivery systems equipped with activated charcoal canisters for passive gas scavenging. In the present study, we surveyed the effectiveness of canisters (attached to well‐maintained precision isoflurane vaporizers) in current use throughout our AAALAC‐accredited laboratory animal facility. Canisters (Omnicon f/air) had been weighed prior to use and then attached to dual‐loop systems (face mask and induction box circuits) from 1 week to 6 months of service. Isoflurane emissions were measured using a pre‐calibrated, portable infrared spectrophotometer by attaching each canister to the face‐mask circuit, occluding the face mask and closing the stopcock to the induction circuit, and running the system at uniform isoflurane concentration (2%) and oxygen flow rate (1 L minute?1). Samples were taken in animal procedure rooms (size range, 45–80 m3) in which the air turnover rate ranged between 20 and 30 nonrecirculating changes per hour. Nine of the 60 canisters (15%) in current use were found to have exceeded the manufacturer's recommended use‐life (defined as a weight increase of 50 g). Of these nine, seven canisters did not scavenge isoflurane at all (indicated by emissions greatly exceeding 100 ppm). Isoflurane was not detected in the operator's breathing zone under normal use conditions (i.e. gas directed to both circuits at once). Of the 51 canisters that had not exceeded their rated use‐life, 12 (23.5%) exhausted isoflurane at >2 ppm. Our data show that (i) the potential for exposure to waste isoflurane emissions will depend on the configuration of the delivery system and that (ii) enhanced attention to canister surveillance may be warranted even in well‐run facilities.  相似文献   
32.
A total of 154 feral pig carcases and 81 kangaroo carcases were examined for the presence of Salmonella, coliforms and total aerobic counts. Approximately 34% of pig carcases yielded one or more serotypes of Salmonella, while about 11% of kangaroo carcases were contaminated with salmonella. The results differed widely between sampling occasions. A total of 13 serotypes were isolated from feral pigs with S. anatum (31 isolates) and S. typhimurium (9 isolates) being the predominant serotypes. Coliforms were isolated from approximately 90% of carcases. The mean log10 coliform count on feral pigs was 4.39 +/- 1.45/g and the mean log10 total count was 6.15 +/- 1.15/g. About 21% of carcases were contaminated with more than 100,000 coliforms/g. A total 3 serotypes were isolated from kangaroos (S. bahrenfeld, S. binza, and S. onderstepoort). The mean log10 coliform count on kangaroos was 3.54 +/- 1.04. More than 50% of kangaroo carcases were contaminated with less than 100 coliforms/g. About 15% of carcases were contaminated with more than 10,000 coliforms/g. The mean log10 total count was 5.2 +/- 1.01/g.  相似文献   
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The serological response of pigs to Erysipelothrix rhusiopathiae inoculation was monitored by a gel diffusion precipitin test (GDPT) using a crude, serotype-specific, autoclaved antigen and an enzyme-linked immunosorbent assay (ELISA) using a heat-extracted, alcohol precipitated and molecular seived antigen previously shown to react with serum from pigs infected with serotypes 1 or 2. All pigs receiving 3 or 5 weekly intravenous inoculations of either a highly virulent (VRS 229) or a lowly virulent isolate (VRS 252) produced GDPT-reactive antibody within 3 weeks, but only 44% were still reactive at 8 to 9.5 weeks. The ELISA response was significantly higher in pigs inoculated with the highly virulent strain, and was similar in pigs receiving 3 or 5 doses of either strain. In a dose-response trial, after 3 doses of VRS 229, GDPT reactivity occurred earlier and was stronger in pigs given higher doses of E. rhusiopathiae, but the response peaked 3 to 5 weeks after the start of challenge and was short lived. GDPT reactivity correlated with dose, but not with the severity of arthritis. The ELISA demonstrated specific IgG antibody was present by 2 weeks, and persisted to at least 11 weeks. The ELISA reactivity was significantly higher in pigs with arthritis than in pigs that received low doses and were not arthritic. Within groups of pigs with arthritis a significant, dose dependent, linear ELISA response developed but did not correlate with the presence or degree of arthritis at slaughter. Non-arthritic pigs had similar low ELISA responses to uninoculated controls.  相似文献   
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Medical records of 40 dogs presented for evaluation of acute-onset, nonprogressive, intracranial dysfunction by means of magnetic resonance imaging (MRI) diagnosis of brain infarction were reviewed. Location of the brain infarcts was: 11 of 38, telencephalic; 8 of 38, thalamic/midbrain; 18 of 38, cerebellar; and 3 of 38, multifocal. Telencephalic infarcts developed within the territory of the middle cerebral (4/11), rostral cerebral (2/11), and striate (5/11) arteries. Thalamic/midbrain infarcts developed within the territory of perforating arteries of the caudal portion of the thalamus and rostral portion of the brainstem (8/8). All cerebellar infarcts (18/38) were within the territory of the rostral cerebellar artery or one of its branches. All infarcts appeared nonhemorrhagic, with marked contrast enhancement observed in only 3 of 38 dogs, all of which were imaged more than 7 days after the onset of signs of neurologic dysfunction. Diffusion-weighted imaging (DWI) sequences were available from 6 dogs, all imaged within 5 days of the onset of signs of neurologic dysfunction. Suspected infarcts were hyperintense on DWI sequences and were hypointense on the apparent diffusion coefficient map. Telencephalic infarcts caused abnormal mental status, contralateral postural reaction deficit, contralateral nasal hypalgesia, contralateral menace deficit, and ipsilateral circling. Thalamic/midbrain infarcts caused contralateral or ipsilateral postural reaction deficit, contralateral menace deficit, ipsilateral head tilt or turn, nystagmus, ventrolateral strabismus, and anisocoria. Cerebellar infarcts caused ipsilateral asymmetric cerebellar quality ataxia, head tilt, intermittent opisthotonus, nystagmus, and ipsilateral menace deficit with apparent normal vision.  相似文献   
37.
Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV) and Ganjam virus (GV) are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated it in a pilot study of the pathogenicity induced by two different isolates of NSDV/GV. One isolate was highly adapted to tissue culture, grew in most cell lines tested, and was essentially apathogenic in sheep. The second isolate appeared to be poorly adapted to cell culture and retained pathogenicity in sheep. The real-time PCR assay for virus easily detected 4 copies or less of the viral genome, and allowed a quantitative measure of the virus in whole blood. Measurement of the changes in cytokine mRNAs showed similar changes to those observed in humans infected by the closely related virus Crimean Congo hemorrhagic fever virus.  相似文献   
38.
Electrocardiographic tracings of an English Bulldog referred for cardiogenic shock due to an orthodromic atrioventricular reciprocating tachycardia conducted with intraventricular conduction disturbance and mimicking ventricular tachycardia (VT) are presented. At admission the surface ECG showed a wide QRS complex tachycardia (WCT) that was converted to sinus rhythm using manual cardioversion (chest thump). This change revealed pre-existing right bundle branch block, and a final diagnosis of supraventricular tachycardia (SVT) with intraventricular conduction disturbance was made. Electrophysiologic study defined the SVT mechanism as an atrioventricular macroreentrant tachycardia mediated by a single mid-septal accessory pathway. The differentiation between various types of WCT is essential when antiarrhythmic therapy is considered. The surface ECG should be systematically evaluated in order to recognize the characteristic features of SVT and VT. Moreover chest thump procedure can be very helpful in the attempt to convert the rhythm to sinus rhythm and to correctly recognize the underlying arrhythmia.  相似文献   
39.
Due to their antioxidant activity, anthocyanins are of increasing interest for nutritionists, food scientists and plant breeders. Anthocyanins in wheat grains are expressed in either the pericarp or aleurone layer. Previous studies revealed that different anthocyanins are present in wheat varieties carrying genes for either the purple pericarp or the blue aleurone trait. Progeny from crosses between red‐, purple‐ and blue‐grained wheat varieties were selected over several cycles for grain colour by visual scoring. Bulked F5 grains were evaluated for their total anthocyanin content by UV‐VIS spectrophotometry and HPLC‐MS. The results demonstrate that it is possible to increase the anthocyanin content by the combination of the different genetic backgrounds for purple pericarp and blue aleurone, even though the majority of progeny were within the range of the purple‐ and blue‐grained check varieties. Visual scoring for grain colour is efficient, reliable and fast for selection in early breeding generations. Advanced breeding lines with high anthocyanin content can be identified by simple extraction methods and spectrophotometric measurements.  相似文献   
40.
This study was performed to evaluate the structural preservation of antral follicles after bovine ovarian tissue vitrification using histological analysis. Ovaries (n = 30) of slaughtered cows were cut into small fragments using a scalpel blade, and the ovarian tissues were randomly assigned to vitrification using 15% dimethyl sulphoxide (DMSO) and 15% ethylene glycol (EG) and fresh tissues (control) groups. For histological evaluations, fresh and post‐thawing ovarian tissues were immediately fixed, serially sectioned into 5‐μm sections and stained with haematoxylin and eosin (H&E). Nine serial sections per fragment were subjected for morphological assessment. The diameter of the antral follicles was determined and classified into four groups: 1 (≤1 mm), 2 (>1–2 mm), 3 (>2–3 mm) and 4 (>3–4 mm). Then, follicular morphology was evaluated in relation to atresia and categorized into seven grades: Grade A (healthy follicle); Grades B, C and D (early atresia); Grades E and F (moderate atresia); and Grade G (advanced atresia). The results revealed that small diameters of antral follicles (1 and 2 mm) were more susceptible for cryoinjury. The normal follicular morphology (Grade A) was not affected by vitrification throughout follicle diameters. Nevertheless, some damage features were monitored after vitrification. In conclusion, the morphological structure of bovine antral follicles could be successfully preserved by ovarian tissue vitrification.  相似文献   
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