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141.
142.
Barbara J. Watrous DVM Peter F. Suter Dr med vet 《Veterinary radiology & ultrasound》1983,24(1):11-24
Cinefluorography and videofluorography were used to record and analyze functional swallowing deficits of 12 dogs with spontaneously occurring oropharyngeal dysphagias and six experimental dogs with selected neurectomies. Ten of the 12 dogs had dysphagias affecting the cricopharyngeal stage of the oropharyngeal phase of swallowing. Two dogs had mixed oropharyngeal dysphagias. Clinical signs of cricopharyngeal dysphagia could not be differentiated from those of dysphagias due to pharyngeal or mixed oropharyngeal deficits. Signs of cricopharyngeal dysphagia consisted of: 1) repeated attempts to swallow; 2) excessive head movement; 3) dropping food from the mouth after unsuccessful swallowing attempts; 4) reingestion of dropped food. Nine of these dogs had cinefluorographic evidence of asynchrony between the normal pharyngeal contraction and relaxation, and subsequent cricopharyngeal relaxation and contraction. Only one dog demonstrated a consistent cricopharyngeal non-opening (achalasia). Seven of the dogs responded dramatically to cricopharyngeal myotomy. Two dogs with mixed oropharyngeal dysphagias had poor contractility of the pharyngeal muscles in addition to cricopharyngeal dysphagia. Clinical and cinefluorographic evaluation following cricopharyngeal myotomy of one dog verified exacerbation of functional deficits due to the iatrogenic cricopharyngeal chalasia. Esophagopharyngeal reflux accentuated the contrast medium retention in the pharynx and laryngotracheal aspiration. The need was stressed for careful differentiation between cricopharyngeal dysphagia and dysphagias involving the pharyngeal stage. Four experimental dogs with selective bilateral neurectomies of branches of the glossopharyngeal (IX) and vagus (X) nerves were evaluated clinically and cinefluorographically in an attempt to identify the pathogenesis of cricopharyngeal dysphagia. The variable results in the four dogs and the observed recovery in two dogs suggested that peripheral motor nerve deficits are not a major cause of cricopharyngeal dysphagia. Glossopharyngeal neurectomy in two dogs induced a profound functional disorder involving the pharyngeal and cricopharyngeal stages and the esophageal phase of swallowing. This would support a new hypothesis that the glossopharyngeal nerve is sensory to the esophagus as well as the pharynx, and may play a major role in disorders of the pharynx, upper esophageal sphincter, and esophagus, including congenital or acquired megaesophagus. 相似文献
143.
Joyce E. Obradovich DVM Stephen J. Withrow DVM Barbara E. Powers DVM PhD Richard Walshaw BVSc 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(2):96-101
Case records of 11 dogs with histologically confirmed carotid body tumors were reviewed. Surgical excision had been attempted in ten dogs with carotid body tumors, and one dog had been euthanatized at diagnosis. There were no intraoperative deaths but perioperative mortality was 40%. Horner's syndrome and laryngeal paralysis were the most common postoperative morbidities. The median survival time after surgery alone in the four dogs that survived the perioperative period was 25.5 months (range, 12-45 months). Two dogs treated with postoperative radiation therapy had survival times of 6 and 27 months. Of the six dogs surviving the perioperative period, two dogs are still alive at 19 and 32 months postoperatively. Of the four dogs that died, one was euthanatized 12 months postoperatively for nontumor-related causes. The remaining three dogs died of distant metastases. The carotid body tumors studied were characterized by local tissue invasion, neurovascular complications after therapy, and a propensity to metastasize to multiple sites in the body. 相似文献
144.
Clive A. Henrick Barbara A. Garcia Gerardus B. Staal David C. Cerf Richard J. Anderson Karen Gill Henry R. Chinn Jeffrey N. Labovitz Michael M. Leippe Sam L. Woo Robert L. Carney Douglas C. Gordon Gustave K. Kohn 《Pest management science》1980,11(2):224-241
A new series of substituted 2-anilino-3-methylbutyrates has been prepared; bioassay data for these compounds on Heliothis virescens, Musca domestica, Aphis fabae and Tetranychus urticae are presented and discussed. Some unexpected relationships were observed between the nature of the substituents and the biological activity. Increases in foliar stability were noted with certain substitution patterns. Both α-cyano-3-phenoxybenzyl 3-methyl-2-(α, α, α,2-tetrafluoro-p-toluidino)butyrate and the corresponding 2-(2-chloro-α, α, α-trifluoro-p-toluidino)-3-methylbutyrate showed good stability in air and light, and exhibited biological activities of a similar nature and potency to those of previously known synthetic pyrethroids. Esters of the (R)-2- anilino-3-methylbutyric acids are far more active than those prepared from the (S)-enantiomers. The (R)-configuration at C-2 in these acids is sterically equivalent to the active absolute configuration at the chiral carbon α to the carboxylate group in both the permethrin and the fenvalerate types of pyrethroids. A new class of insecticidal 2-(isoindolin-2-yl)alkanoates is also reported. In this series the most biologically active analogue was α-cyano-3-phenoxybenzyl 3-methyl-2-(4,5,6,7-tetrafluoroisoindolin-2-yl)butyrate. These esters were considerably less stable than the anilino analogues on exposure to air and light. 相似文献
145.
146.
147.
Sexual dimorphism of the kidney in the NMRI mouse as shown by Dolichos biflorus agglutinin labelling
Johanna Plendl Barbara Schoenlejber W. Schmahl A. Beatrice Murray F. Sinowatz 《Anatomia, histologia, embryologia》1992,21(2):118-126
The histological affinity pattern of Dolichos biflorus agglutinin (DBA) in kidneys from mice (NMRI, Balb/c, CBA) and rats (Wistar) fixed by perfusion with formalin, Bouin, or HgCl2 was investigated with a horseradish peroxidase conjugate. The animals were examined from fetal stage to adulthood. Adult female NMRI mice exhibited constant DBA labelling, with DBA binding to cells of the proximal and collecting tubules. Moreover the vascular endothelium of the renal papilla was found to be DBA-positive in 50% of adult female animals. In contrast, there was only very little DBA binding in the kidneys of male adult NMRI mice. There was no sexual dimorphism in lectin labelling in kidneys from other strains of mice or from rats. 相似文献
148.
ULTRASONOGRAPHIC EVALUATION OF THE FETUS AND INTRAUTERINE ENVIRONMENT IN HEALTHY MARES DURING LATE GESTATION 总被引:3,自引:0,他引:3
Virginia B. Reef DVM Wendy E. Vaala VMD Leila T. Worth VMD PhD Pamela A. Spencer ScM Barbara Hammett 《Veterinary radiology & ultrasound》1995,36(6):533-541
Mares with uncomplicated pregnancies (n = 33) underwent transabdominal sonography to evaluate fetal well-being, obtain measurements of fetal size and characterize the intrauterine environment. Data from the last examination obtained prior to parturition were used for statistical analysis. All mares had one active fetus with good fetal tone. The maximal vertical depth of amniotic fluid (7.9 ± 3.5 cm) was less than allantoic (13.4 ± 4.4 cm) and fewer echogenic particles were detected in amniotic fluid. The maximal uteroplacental thickness was 1.38 ± 0.23 cm (retrospective) and 1.15 ±± 0.24 cm (propspective). In 3 mares small anechoic spaces were imaged between the uterus and placenta. Fetuses had a regular cardiac rhythm with a mean heart rate of 75 ± 7 beats/minute and breathing movements. The diameter of the fetal aorta (mean = 22.8 ± 2.15 mm) was significantly correlated with neonatal foal weight (P<0.0008, r = 0.72) and maternal prepartum weight (P<0.002, r = 0.86). This information of the normal intrauterine environment and fetal well-being can be used to develop a biophysical profile specific for the equine fetus. 相似文献
149.
HOST PLANTS OF WHEAT BULB FLY 总被引:1,自引:1,他引:0
150.