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121.
Most of the studies on organic acids and sugars in citrus were performed during fruit maturation, and less is known before this stage of development. The aim of our study was to investigate acids and sugars in lemon, lime, and orange from fruit-set toward development. We chose to compare organic acid and sugar accumulation among acidic and acidless varieties within three species. We estimated the acidity by titrimetry and quantified the concentrations of seven organic acids and three sugars by reverse HPLC. During the first 50 days of development, quinic acid was the major organic acid whatever the variety. Afterward, citric acid predominated in acidic varieties, while in acidless, malic acid exceeded it. Fructose substituted citric acid in acidless and could be synthesized either from citric acid or directly from glucose. Our results provided the first complete report on sugar and organic acid accumulation during the early stages of fruit development in several citrus varieties.  相似文献   
122.
Background – Hypersensitivity dermatitides (HD) are frequently suspected in cats, but there are few clinical studies on safe and effective treatments in the published literature. Objectives – To establish a safe and effective dose of ciclosporin in the treatment of feline HD. Animals – One hundred client‐owned cats with feline HD. Methods – Double‐blind study, with cats randomly assigned to receive ciclosporin at either 7.0 mg/kg once daily (n = 33) or 2.5 mg/kg once daily (n = 32) or a placebo (n = 35) for 6 weeks. Results – Mean Total Lesion Scores with 7.0 mg/kg ciclosporin were significantly lower than with 2.5 mg/kg ciclosporin (P = 0.0047) or placebo (P = 0.0003) at study end. Individual Total Lesion Scores improved by >50% in 70% of the 7.0 mg/kg group, compared with 47% in the 2.5 mg/kg group and 23% in the placebo group (P = 0.0006). The investigators’ Global Assessment of Improvement was ‘excellent’ or ‘good’ in 61% of cats treated with 7.0 mg/kg ciclosporin, compared with 47% of cats given 2.5 mg/kg and 23% given placebo. The improvement in Investigator Pruritus Scores was significantly greater in cats treated with 7.0 mg/kg ciclosporin (54%) compared with both 2.5 mg/kg ciclosporin (32%; P = 0.0232) and placebo (21%; P = 0.0063). Mild gastrointestinal disorders were the most common adverse events, but these did not require cessation of therapy. Conclusions and clinical importance – Results suggest that 7.0 mg/kg ciclosporin once daily in food or per os for 6 weeks is effective and well tolerated in feline HD.  相似文献   
123.
In 2006, a cross-sectional survey was carried out in 206 herds in southern Belgium to estimate the proportion of herds with Q fever-seropositive bulk tank milk (BTM), i.e. herds with an intra-herd seroprevalence >10%. Of the tested herds, 119 (57.8%; 95% CI: 51.1-64.4%) were seropositive. Most had a low antibody titre. Of these herds, 50 were randomly subjected to a real time Coxiella burnetii PCR analysis. The proportion of herds excreting Coxiella in BTM was 30.0% with only 2.0% of herds having a high level of shedding. An additional questionnaire and logistical regression identified some factors which increased the risk of BTM seroconversion (in heifers, drinking water from watercourse or well water) and some which decreased it (in heifers, tie- and free-stalling, and animals of all age in the same shed; in heifers and cows, shed disinfection).  相似文献   
124.
One hundred and twenty five chickens from Grenada, consisting of 77 broilers and 48 layers were examined for carriage of thermophilic campylobacters in their ceca by culture. Seventy nine percent of chickens were positive for campylobacters, with an isolation rate of 93.5% for broilers and 56.3% for layers, the difference being significant. Sixty-four pure cultures comprising 39 Campylobacter coli, 21 Campylobacter jejuni, and 4 Campyilobacter lari isolates were tested for their resistance against 7 antibiotics using the E-test. None of the isolates were resistant to chloramphenicol and gentamicin. Resistance rates to other drugs were: ampicillin, 9.4%; ciprofloxacin, 12.5%; erythromycin, 3.1%; metronidazole, 9.4%, and tetracycline, 50% with MICs of >or=256 microg/mL for tetracycline. There were no significant differences in resistance rates between C. coli and C. jejuni. Multiple resistance to >or=2 drugs was seen in 15.6% of total isolates. All C. lari isolates were resistant to ciprofloxacin, and 3 of 4 isolates had multiple drug resistance. Overall, erythromycin, which is the drug of choice for treatment of Campylobacter infections in humans, is effective in vitro against 97% of chicken isolates in Grenada.  相似文献   
125.
Water from 48 channel catfish Ictalurus punctatus ponds at Auburn and Greensboro, Alabama, USA, usually contained less than 1,000 total coliform and 200 fecal coliform bacteria per 100 mL. There were no sources of human fecal matter to ponds. Also, the fecal coliform: fecal streptococci ratio was less than 1.0 and typical of fecal contamination by warm-blooded animals other than humans. The abundance of coliforms was greater in spring and summer than in fall and winter in catfish ponds and sportfish ponds at Auburn, Alabama. In spite of high organic matter inputs in feed, catfish ponds had no greater abundance of coliforms than sportfish ponds.  相似文献   
126.
The technique of polymerase chain reaction (PCR) associated to hybridization was used to screen 123 samples collected from wild and synanthropic rodents captured in a cutaneous and visceral leishmaniasis endemic area in the State of Minas Gerais, Brazil. The detection of Leishmania spp in naturally infected rodents is of fundamental importance for incriminating them as possible reservoir hosts of the diseases in Minas Gerais. A total of 62 specimens belonging to wild (Thrichomys apereoides, Oryzomys subflavus, Galea spixii, Bolomys lasiurus and Wiedomys pyrrhorhinos) and synanthropic (R. rattus) rodent species were captured in different ecotopes. Blood and skin samples were submitted for PCR analyses followed by molecular hybridization with specific probes for the three Leishmania-species complexes. Fifteen samples were found positive after PCR-hybridization and identified as follows: nine belonging to the L. mexicana complex, three to the L. braziliensis complex and three to the L. donovani complex. Positive PCR results were found in 11 out of the 61 (18%) blood samples and in four out of the 62 (6.4%) skin fragments screened. R. rattus and T. apereoides were the most abundant species in the area also presenting high prevalence of natural infection. The presence of parasite DNA belonging to L. braziliensis, L. mexicana and L. donovani complexes was confirmed in several individuals of a rodent species, R. rattus. This work is the first report of the detection of L. (L.) chagasi in a naturally infected T. apereoides. The utility of filter paper as a substrate for PCR analyses and the efficacy of the procedure associated to the hybridization is emphasized.  相似文献   
127.
The kaka (Nestor meridionalis) is a threatened, endemic New Zealand parrot that is declining primarily because of predation by introduced mammals. Numbers of female kaka surviving to sexual maturity more than compensated for adult female mortality at three sites with predator control but not at three unmanaged sites. Nesting success at the sites with predator control was significantly greater (?80%) than at unmanaged sites (?38%) while predation on adult females was significantly less (5% c.f. 65%). Predation was the most common cause of nesting failure at all sites. Stoats (Mustela erminea) appeared to be the main predator, although evidence of possum (Trichosurus vulpecula) predation on eggs, nestlings and nesting females was also found. These results suggest that control of stoats and possums can potentially reverse the decline of the kaka on the main islands of New Zealand.  相似文献   
128.
A sexagenarian couple operating a dairy farm, where there were also many horses, suffered a severe respiratory infection associated with the bacterium Streptococcus equi ssp. zooepidemicus. The investigation revealed that the source of infection was due to contacts with a horse having an infected wound from which we isolated this zoonotic agent.  相似文献   
129.
A retrospective study of the medical records of 33 horses was performed to determine the clinical and diagnostic abnormalities associated with temporohyoid osteoarthropathy. Data collected from medical records included signalment, presenting complaints, history, physical examination findings, laboratory data, results of diagnostic imaging studies, and treatments. Follow-up information was obtained from a review of case records; by telephone conversation with the owner, veterinarian, or trainer; or by both methods. Of 33 horses with temporohyoid osteoarthropathy, 29 presented with facial nerve (cranial nerve VII) deficits and 23 presented with vestibulocochlear nerve (cranial nerve VIII) deficits. Guttural pouch endoscopy was more reliable than radiography for diagnosis. Of horses with unilateral clinical signs, 22.6% actually had bilateral disease. Magnetic resonance imaging and computed tomography identified the lesions in all horses in which these tests were performed. Of 30 horses for which follow-up information was obtained, 20 (67%) were alive. Eight horses were euthanized and 1 died because of problems associated with temporohyoid osteoarthropathy. Nineteen of 20 surviving horses (95%) were considered by the owner or trainer to be suitable for athletic use. Twelve surviving horses (60%) had residual facial nerve deficits; 11 horses (55%) had residual vestibulocochlear nerve deficits. Horses with temporohyoid osteoarthropathy have a fair prognosis for return to some type of athletic function, but there is risk of acute death. The majority of horses would be expected to have some residual cranial nerve dysfunction, and it could take a year or longer for maximal improvement to occur.  相似文献   
130.
Nutrient-agar plates containing isoxaben (500 mg litre(-1)) were used to isolate isoxaben-metabolising bacteria from four European soils incubated with the herbicide under laboratory conditions. In flask experiments, inoculation of a basal salts medium containing nitrogen and [phenyl-U-14C]isoxaben with an isolate (B2b) resulted in 33% recovery of the initial radioactivity as [14C]carbon dioxide after 2 weeks. A major metabolite identified by GC-MS and NMR analysis as 3-(1-ethyl-1-methylpropyl)isoxazol-5-ylamine accumulated both in basal salts and nutrient broth media. 2,6-Dimethoxybenzoic acid, a suspected metabolite of isoxaben, was not detected in either liquid media. However, the capability of the B2b isolate to use 2,6-dimethoxybenzoic acid as a source of carbon was demonstrated. Soil inoculation with the B2b strain resulted in an increase in the recovery of [14C] carbon dioxide from both [phenyl-U-14C] and [isoxazole-5-14C]isoxaben. The metabolite identified as 3-(1-ethyl-1-methylpropyl)isoxazole-5-ylamine only accumulated if the soil was autoclaved before inoculation. This metabolite was rapidly mineralized by the microflora of a natural soil without history of isoxaben treatment. Homology patterns of sequenced 16S rDNA between isoxaben-transforming isolates and reference strains showed that the four isolates identified belonged to the genus Microbacterium.  相似文献   
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