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791.
Dogs with clinical signs typical of cauda equina syndrome require careful evaluation to determine the cause of the disease as this strongly influences choice of treatment. Possible aetiologies include congenital or developmental, inflammatory, traumatic, neoplastic, and degenerative lesions that may involve vertebrae, vertebral joints, intervertebral discs, spinal cord, spinal nerves, or meninges. It must be determined whether clinical signs are due to musculoskeletal or neurological disease before performing special radiographic procedures. Non-contrast radiography permits false-positive diagnosis of obvious degenerative changes involving the L-S disc that may be without clinical signs or permits a false-negative diagnosis due to the failure to appreciate soft tissue lesions not seen radiographically. Special radiographic techniques are recommended and include: (1) stress radiography, (2) discography, and (3) epidural myelography. Evaluation of the results of these studies assists in determining the cause of the cauda equina syndrome and the type of therapy required.  相似文献   
792.
Colonization characteristics of Campylobacter jejuni in chick ceca   总被引:7,自引:0,他引:7  
We report our findings on several parameters influencing cecal colonization of chickens by Campylobacter jejuni. Thirty-five colony-forming units (CFU) of a composite culture of C. jejuni colonized the ceca of one-half of the newly hatched chicks challenged by oral gavage. A challenge dose of 3500 CFU/chick consistently colonized the ceca of all chicks challenged. Challenge doses of approximately 10(5) CFU of C. jejuni per chick resulted in consistent cecal colonization, regardless of whether the birds were challenged 1, 2, or 3 days post-hatch. Four isolates showed consistently strong cecal colonization abilities, whereas two isolates colonized the ceca in only 20 of 122 chicks when given levels of 10(5) CFU per chick. One of these poorly colonizing isolates was repeatedly transferred by fecal-oral passage through chicks; subsequently, this isolate was able to consistently colonize chicks. Competitive exclusion (CE) microflora did not diminish the colonization rates for C. jejuni. Birds treated with five different CE cultures were colonized at a rate of 81 of 84 chicks; control chicks were similarly consistently colonized (45 of 46 chicks).  相似文献   
793.
The concentrations of serum proteins (beta 1, beta 2, gamma, alpha 1, alpha 2 globulins and albumin) and absolute numbers of eosinophils, neutrophils and lymphocytes were examined in 64 naturally infected horses and ponies in which the number of larvae of Strongylus vulgaris in the cranial mesenteric artery and the severity of the lesion of verminous arteritis could be determined. The horses were grouped according to the number of larvae found and the severity of the arteritis. The results demonstrated that, although some significant deviation from a random distribution occurred in certain of the values (chi 2 test), there was considerable individual variation in the values obtained for individual animals within groups and overlap of the range of values between groups. Also the number of larvae present in the artery did not necessarily accurately reflect the severity of the arterial lesion. Thus, the parameters examined could not be used reliably to estimate the intensity of infection with S vulgaris in an individual animal.  相似文献   
794.
795.
The lengths of individual symbiotes and the numbers of these per unit area in ultrathin sections of the mycetomes did not differ significantly between strains of Myzus persicae (Sulz.) that were resistant or susceptible to demeton-S-methyl in Britain. This is contrary to observations made in Germany on the symbiotes of similar aphids resistant or susceptible to parathion.  相似文献   
796.
797.
Infection of the peritoneal cavity with cestode larvae, presumptively diagnosed as tetrathyridia of the genus Mesocestoides, was found by exploratory celiotomy in a dog with clinical signs consisting of episodic anorexia, vomiting, and depression. Lymphopenia and hypoalbuminemia were associated clinicopathologic abnormalities. Dystrophic calcification and midline duodenal displacement were found on abdominal radiographs. Therapy with mebendazole was instituted after recurrence of the initial episodic clinical signs postoperatively. Daily use of mebendazole for intermittent periods of up to 3 months led to remission of gastrointestinal signs for 30 months. However, 17 months after the initial diagnosis, infection of the vaginal tunic of the testicle with similar cestode larvae necessitated castration and removal of the vaginal tunic to the inguinal ring. Mebendazole therapy was reinstituted and continued for 31/2 months postoperatively. The dog was free of clinical signs of infection during and for the 16 months since this period of treatment.  相似文献   
798.
A new inhibitor of superficial scald, phorone (2,6-dimethylhepta-2,5-dien-4-one) is reported. Phorone reduced scald on ‘Granny Smith’ apples when applied by injection or as a vapour. Phorone was found to limit the accumulation of α-farnesene during storage and the amounts of conjugated triene oxidation products derived from α-farnesene. Monoterpenes also reduced α-farnesene, oxidation products and scald, but these compounds were less effective than phorone. In contrast, diphenylamine had little effect on the amount of α-farnesene in the fruit but it prevented the autoxidation of α-farnesene and controlled scald.  相似文献   
799.
800.
The agricultural/livestock system of a 40,000 km2 area in western Sudan is described. Details of the three main components—traditional rainfed agriculture, small-scale irrigation and animal husbandry—are given. Data on crop yields and livestock production at both the unit level and the system level are provided. Millet is the main cereal crop overall but sorghum occupies an important place in the intensively cultivated alluvial zones. Cash crops, including groundnuts, chillies and okra for drying, are of some importance. Onions are the main winter irrigated crop while mangoes and citrus are important tree crops. The livestock sector is dominated by cattle which account for more than 75% of the livestock units present. Gross output of the area at 1976 prices was calculated at £Sud 14·8 to £Sud 16·2 million (US$ 41·4 to US$ 45·4 million) equivalent to £Sud 41·7 to £Sud 45·6 per head of population and £Sud 3·70 to £Sud 4·05 per hectare. Of these totals between 33 and 36% could be attributed to livestock production.  相似文献   
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