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31.
Most studies that investigate the prevalence of infections with feline leukemia virus (FeLV) are based on the detection of p27 antigen in blood, but they do not detect proviral DNA to identify the prevalence of regressive FeLV infections. The aim of the present study was to assess the prevalence and status of FeLV infection in cats in Southern Germany. P27 antigen enzyme-linked immunosorbent assay (ELISA), anti-p45 antibody ELISA, DNA polymerase chain reaction (PCR) of blood and RNA PCR of saliva were performed. Nine out of 495 cats were progressively (persistently) infected (1.8%) and six were regressively (latently) infected (1.2%). Cats with regressive infections are defined as cats that have been able to overcome antigenemia but provirus can be detected by PCR. Twenty-two unvaccinated cats likely had abortive infections (regressor cats), testing FeLV antigen- and provirus-negative but anti-p45 antibody-positive. Most of the FeLV-vaccinated cats did not have anti-FeLV antibodies. Both progressive, as well as regressive infections seem to be rare in Germany today.  相似文献   
32.
Based on isolations from naturally infected fish in Florida, we investigated the role of the fungi Aphanomyces invadans, Achlya bisexualis, and Phialemonium dimorphosporum in the etiology of ulcerative mycosis (UM) in striped mullet Mugil cephalus. We injected healthy striped mullet subcutaneously with secondary zoospores of four oomycete isolates: two concentrations (50 and 115 zoospores/mL) of SJR (an endemic isolate of Aphanomyces invadans in American shad Alosa sapidissima from the St. Johns River); two concentrations each of CAL (25 and 65 zoospores/mL) and ACH (1,400 and 2,000 zoospores/mL; endemic isolates of Aphanomyces invadans and Achlyva bisexualis, respectively, in striped mullet from the Caloosahatchee River); and two concentrations of the ascomycete culture MTZ (2,500 and 3,500 zoospores/mL; endemic isolate of P. dimorphosporum from whirligig mullet M. gyrans in the Matanzas Inlet). All fish injected with either concentration of SJR developed granulomatous ulcers after 8 d and died within 21 d. Eighty percent (8/10) of fish injected with the high dose of CAL developed ulcers after 13 d and died within 28 d, but only 30% (3/10) of fish injected with the low dose of CAL developed ulcers. Four of the ulcerated fish died within 28 d, and the remaining fish were terminated after 32 d. Fish injected with zoospores of Aphanomyces invadans developed ulcers that were grossly and histologically similar to those observed in naturally infected striped mullet with UM from several estuaries or rivers in Florida. These hemorrhagic skin ulcers were characterized by myonecrosis and the presence of mycotic granulomas. None of the fish injected with ACH, MTZ, or sterile water developed ulcers. This study fulfilled Koch's postulates and demonstrated that ulcers could be experimentally induced in striped mullet after exposure via injection to secondary zoospores of an endemic Florida strain of Aphanomyces invadans.  相似文献   
33.
Two main factors have impeded the progress of work on the lymphatic vessels…, namely lack of methods of investigation and lack of interest. The latter has been partly due to the paucity of efective therapeutic methods to deal with lymphatic vessel disorders.  相似文献   
34.
Technetium-99m hexamethylpropyleneamine oxine (99mTc-HMPAO) and Indium-111 oxine (111In-oxine) labeled canine gramulocytes were evaluated in vitro over a six hour period. Labeling efficiency for 99mTC-HMPAO and 111In-oxine labeled granulocytes was 39.6%± 8.0% and 60.6%± 17.6% (mean ± SD) respectively. The mean in vitro elution of the radiolabel ranged from 8.7-14.0% for the 99mTc-HMPAO grannulocytes and from 6.1-9.0% for the 111In-oxine granulocytes. Mean cell viability, for the 99mTc-HMPAO, 111In-oxine and non-radiolabeled control granulocytes ranged from 97.8-99.4%, 96.4-98.5% and 98.2-99.0%, respectively. The phagocytic ability of the 99mTc-HMPAO, 111In-oxine and control granulocytes ranged from 47.5-54.1%, 38.9-56.2% and 46.6-57.8% respectively over the six hour study period. Although labeling efficiency using 111In-oxine was significantly (P=0.05) better than 99mTc-HMPAO, there was no significant difference in label retention of the two radiolabels. There was no significant difference in viability or phagocytic function during the six hour study period. Considering the potential cost advantage and the superior imaging qualities of Technetium-99m relative to Indium-111, 99mTc-HMPAO appears to be a good alternative to 111In-oxine as a granulocyte label.  相似文献   
35.
OBJECTIVE: To validate four scales -- outcome expectancies for purchasing fruit and for purchasing vegetables, and comparative outcome expectancies for purchasing fresh fruit and for purchasing fresh vegetables versus other forms of fruit and vegetables (F&V). DESIGN: Survey instruments were administered twice, separated by 6 weeks. SETTING: Recruited in front of supermarkets and grocery stores; interviews conducted by telephone. SUBJECTS: One hundred and sixty-one food shoppers with children (18 years or younger). RESULTS: Single dimension scales were specified for fruit and for vegetable purchasing outcome expectancies, and for comparative (fresh vs. other) fruit and vegetable purchasing outcome expectancies. Item Response Theory parameter estimates revealed easily interpreted patterns in the sequence of items by difficulty of response. Fruit and vegetable purchasing and fresh fruit comparative purchasing outcome expectancy scales were significantly correlated with home F&V availability, after controlling for social desirability of response. Comparative fresh vegetable outcome expectancy scale was significantly bivariately correlated with home vegetable availability, but not after controlling for social desirability. CONCLUSION: These scales are available to help better understand family F&V purchasing decisions.  相似文献   
36.
A 14-year-old, spayed female Cocker Spaniel was presented to the Boren Veterinary Medical Teaching Hospital at Oklahoma State University with acute loss of vision in the right eye and a history of intermittent bloody diarrhea of unknown duration. Small, white, plaque-like lesions in the retina and subretina were visualized by direct ophthalmic examination, and aspirated with ultrasound-guidance. A direct smear of the subretinal fluid was highly cellular and contained large numbers of pleomorphic organisms consistent with Prototheca sp. The structures were round, oval, or elongated, 4-6 microm width and 8-16 microm in length and surrounded by a thin, clear cell wall. Small, central, pink to purple nuclei were observed in some organisms, but in most, the nuclei were obscured by a deeply basophilic, granular cytoplasm. Some organisms contained endospores. Negatively-stained structures of similar size and shape were considered to be empty casings (theca) of ruptured sporulating and nonsporulating forms of the organism. Protothecosis usually is a disseminated, fatal disease in dogs. The Prototheca organisms observed in this case showed characteristic morphology, illustrating the ability to diagnose protothecosis in cytologic samples.  相似文献   
37.
Riparian forests are assumed to play a crucial role in the global carbon cycle. However, little data are available on C stocks of floodplains in comparison to other terrestrial ecosystems. In this study, we quantified the C stocks of aboveground biomass and soils of riparian vegetation types at 76 sampling sites in the Donau‐Auen National Park in Austria. Based on our results and a remotely sensed vegetation map, we estimated total C stocks. Carbon stocks in soils (up to 354 t ha–1 within 1 m below surface) were huge compared to other terrestrial ecosystems. As expected, soils of different vegetation types showed different texture with a higher percentage of sandy soils at the softwood sites, while loamy soils prevailed at hardwood sites. Total C stocks of vegetation types were significantly different, but reflect differences in woody plant biomass rather than in soil C stocks. Mature hardwood and cottonwood forests proved to have significantly higher total C stocks (474 and 403 t ha–1, respectively) than young reforestations (217 t ha–1) and meadows (212 t ha–1). The C pools of softwood forests (356 t ha–1) ranged between those of hardwood/cottonwood forests and of reforestations/meadows. Our study proves the relevance of floodplains as possible C sinks, which should be increasingly taken into account for river management. Furthermore, we conclude that plant‐species distribution does not indicate the conditions of sedimentation and soil C sequestration over the time span of interest for the development of soil C stocks.  相似文献   
38.
The growth of herbicide-resistant canola varieties increased from 10% of the canola area in Canada in 1996, when the technology was first introduced, to 80% in 2000. From 1995 to 2000, the amount of herbicide active ingredient applied per hectare of canola declined by 42.8% and the Environmental Impact (EI) per hectare, calculated using the Environmental Impact Quotient for individual herbicides and the amounts of active ingredients applied, declined 36.8%. The amount of herbicide active ingredient per hectare applied to conventional canola was consistently higher than that applied to herbicide-resistant canola each year between 1996 and 2000. Similarly, the EI of herbicide use per hectare in conventional canola was higher than that of herbicide-resistant canola during the same time period. Since 1996, herbicide use has shifted from broadcast applications of soil-active herbicides to post-emergence applications of herbicides with broad-spectrum foliar activity. The decline in herbicide use and EI since the introduction of herbicide-resistant varieties was due to increased use of chemicals with lower application rates, a reduced number of applications and a decreased need for herbicide combinations.  相似文献   
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40.
Chylothorax is a devastating disease, and the success rates from either medical or surgical management are less than satisfactory. In some animals with chylothorax, a thickening of the pericardium occurs that is associated with chronic irritation induced by chyle. We hypothesized that pericardial thickening would lead to increased right-sided venous pressures and that abnormal venous pressures would act to impede the drainage of chyle via lymphaticovenous communications after thoracic duct (TD) ligation. We also hypothesized that serosanguineous effusions that occurred after TD ligation could effectively be treated or prevented by pericardectomy in affected animals. TD ligation plus pericardectomy was performed in 17 animals, and pericardectomy alone was performed in an additional 3 animals that presented during a 5.5-year period to the Texas A&M University (College Station, TX). Nineteen animals presented for an evaluation of idiopathic chylothorax (9 dogs and 10 cats), and 1 dog presented for serosanguineous pleural fluid after TD ligation that had been performed elsewhere. Echocardiography was normal in all animals, except for a subjectively thickened pericardium in 7 cats and 6 dogs. Clinical signs of pleural fluid accumulation resolved in 10 of 10 dogs and in 8 of 10 cats after surgery. The overall success rate for the surgical treatment of chylothorax (ie, the resolution of pleural fluid accumulation) in this study was 90% (100% in dogs and 80% in cats). These data suggest that TD ligation in conjunction with pericardectomy has a favorable outcome in animals with idiopathic chylothorax.  相似文献   
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