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871.
After giving an account of the principles of pressure measurement in flowing air and a review of the literature on tracheal catheters, the authors describe the construction, the introduction and the function of their own transtracheal catheter. This is a teflon catheter with several side–ports which is introduced into the cervical trachea by a guide technique. After introduction, the catheter is stiffened by the insertion of 2 steel wires. The catheter was studied in model experiments concerning: a) the ability to measure the static pressure in flowing air, and b) the dynamic accuracy of a recording system built up around the catheter.The results indicated that the intratracheal pressure sensed in exercising horses well reflected the static pressure, and that the dynamic accuracy of the recording system was good to about 60 Hz. The present technique of recording the intratracheal pressure was used on 122 occasions in 69 exercising horses with only one complication referable to the catheter occurring. The transtracheal route of catheterisation may be superior, as catheters introduced by this route do not appear to influence the function of the pharynx and larynx. In contrast, nasotracheal catheters that traverse the larynx, might interfere with the respiratory function. kw|Keywords|k]upper airway obstruction k]frequency response 相似文献
872.
The morphologic and morphometric features of the lower respiratory system in mole rats were examined. It was seen that the low respiratory system of this species leading a special life under highly hypoxic/hypercapnic conditions underground is structurally similar to other mammals living on land in terms of the parts examined; trachea was formed by 29.5 ± 4 oval‐formed cartilaginous tracheals arranged backwards and became gradually more stenotic diameter from cranial to the caudal of the neck. The trachea was separated in two principal bronchus at the fourth thoracal intercostal spatium level. The angle between the two main principal bronchi was 60.5 ± 2.35°. The lung constituted 1.29 ± 0.03% of the body weight and the right lung was heavier than the left lung. Fissura inter‐lobaris was deep and separated the lung lobes wholly, and the right lung was separated in four lobes, whereas the left lung was not separated into the lobes. Also, the medial lobe of the left lung was the lightest lobe. 相似文献
873.
Y. R. A. van Zeeland A. Lennox J. F. Quinton N. J. Schoemaker 《The Journal of small animal practice》2014,55(11):593-596
Preputial tumours in ferrets are frequently malignant and therefore warrant prompt investigation. As many cases do not respond favourably to surgery, even in combination with radiation therapy, wide surgical resection has been recommended. Such a procedure may necessitate partial or total penile resection but outcomes have thus far not been well described. The current case series describes two ferrets in which surgical resection, including penile amputation, was performed using 10 and 5 mm margins, respectively. In the first case, no recurrence of preputial gland adenocarcinoma was noted for 32 months postsurgery, whereas multiple attempts at surgery and radiation therapy were unsuccessful in the second. These cases suggest that margins of at least 1 cm may help achieve a better outcome. Penile amputation for the treatment of preputial tumours appears to be well tolerated by ferrets, as demonstrated by these cases. 相似文献
874.
875.
With 8 figures SUMMARY: This study aimed at revealing the origin, course and distribution of the hypoglossal nerve in 20 adult male New Zealand rabbits. In all the animals dissected, the hypoglossal nerve arose from the ventrolateral side of the medulla oblongata with two main roots and gave off a descending branch to the ansa cervicalis before reaching the division of the common carotid artery. This branch was not seen on the right side of only one case. At the lateral aspect of the hyoglossus muscle, the nerve then divided into the lateral and medial main branches, sent branches to the styloglossus, hyoglossus, genioglossus and geniohyoideus muscles and terminated in the intrinsic tongue muscles. A communicating branch was observed between the hypoglossal and accessory nerves in the right side of one animal and between the hypoglossal nerve and the ganglion nodosum in the right retropharyngeal area of another animal. An additional branch was observed innervating the stylohyoideus muscle in one animal only. A lateral lingual-hypoglossal communication was also seen between the lateral branch of the hypoglossal nerve and terminal branches of the lingual nerve. 相似文献
876.
Wedley AL Maddox TW Westgarth C Coyne KP Pinchbeck GL Williams NJ Dawson S 《The Veterinary record》2011,168(13):354
The prevalence of carriage of antimicrobial-resistant (AMR) and extended-spectrum β-lactamase (ESBL)-producing Escherichia coli was determined in 183 healthy dogs from a semi-rural community in Cheshire. Isolates were tested against a panel of antimicrobials and by PCR to detect resistance genes. In the suspected ESBL-producing isolates, the presence of bla(SHV), bla(TEM), bla(CTX-M) and bla(AmpC) genes was determined by PCR and sequencing. A total of 53 (29 per cent, 95 per cent confidence interval [CI] 22.4 to 35.5 per cent) dogs carried at least one AMR E coli isolate. Twenty-four per cent (95 per cent CI 17.9 to 30.2 per cent) of dogs carried isolates resistant to ampicillin, 19.7 per cent (95 per cent CI 13.9 to 25.4 per cent) to tetracycline and 16.9 per cent (95 per cent CI 11.5 to 22.4 per cent) to trimethoprim. A bla(TEM) gene was detected in 39 of 54 ampicillin-resistant isolates, a tet(B) gene in 12 of 45 tetracycline-resistant isolates, and a dfr gene in 22 of 33 trimethoprim-resistant isolates. Multidrug-resistant isolates were demonstrated in 15 per cent (28 of 183; 95 per cent CI 10.1 to 20.5 per cent) of dogs. Nine suspected ESBL-producing E coli were isolated, of which only one was confirmed by double disc diffusion testing. Two of these isolates carried the bla(TEM-1) gene and seven carried the bla(CMY-2) gene. 相似文献
877.
Blood was obtained from 61 neonatal Holstein calves originating from a farm in Germany with a high incidence of bovine neonatal pancytopenia (BNP). In order to detect alterations that might be related to BNP, selected haematological analytes were determined. Haematological examinations demonstrated alterations in at least two of the three cell lineages in 10 calves (16.39 per cent). Six animals (9.84 per cent) developed a bleeding disorder indicative of BNP at approximately two weeks of age. None of these animals showed alterations in complete blood cell count at sampling in the first week of life. In weeks when calves with BNP were born, an increase in the number of apparently healthy calves demonstrating decreases in blood cell counts was observed. 相似文献
878.
The aim of this questionnaire-based retrospective study was to ascertain veterinary practitioners in the British Isles' approaches to osteoarthritis in dogs. The Mann-Whitney U test, Kruskal-Wallis test and multiple ordinal logistic regression were used to compare demographic data with treatment options. Questionnaires were returned by 228 practitioners (a response rate of 22.8 per cent). The majority of responses were from males (70 per cent). Eighty-six per cent (188 of 220) of the respondents had graduated from veterinary schools in the UK and Ireland. Veterinarians who had graduated less recently used exercise modulation less frequently (P<0.004, odds ratio [OR]=1.06) and ranked exercise modulation as less important (P=0.008, OR=1.04). Veterinarians who had graduated outside the UK or Ireland were less likely (P=0.033, OR=0.46) to use exercise modulation than those who had graduated in the UK or Ireland. Veterinarians who had graduated more recently were less likely (P=0.008, OR=0.95) to use medications. Female veterinary surgeons were less likely to rank medications as important (P<0.0001, OR=0.29) and less likely to rank corticosteroids as important (P=0.046, OR=0.42) than male veterinary surgeons. Practitioners who had graduated outside the UK or Ireland were less likely (P=0.01, OR=0.30) to rank corticosteroids as important. There was a significant mild negative correlation between the frequency of use of structure-modifying osteoarthritis drugs (SMOADs) and practitioners' opinions on rank importance (-0.32, P<0.0001). Medications such as SMOADs and nutraceuticals were ranked as not important but were used frequently. Overall, age, sex, the university of graduation and the number of canine consultations per day had an impact on the practitioners' treatment protocols. 相似文献
879.
880.
The interest in the effect of genotype × environment interaction is increasing because animal breeding programs have become geographically broader. Climate changes in the next decades are also expected to challenge the present breeding goals, increasing the importance of environmental sensitivity. The aim of this work was to analyze genotype × environment interaction effect on cattle BW using the environmental sensitivity predicted by random regression reaction norm models, including sex and age effects as additional dimensions in the study. Genetic parameters were estimated for adjusted BW of Brazilian Nelore cattle at different ages (120, 210, 365, and 450 d), using linear polynomials for random regression analysis. The analyses with sex as a fixed effect (total analyses) were compared with those with sex-separated progenies (male and female progeny analyses, respectively). (Co)variance components were estimated and breeding values calculated EPD. The results showed important differences in reaction norm model genetic parameter estimates according to different age and sex analyses. The results confirmed the presence of an important genotype × environment × sex × age interaction for Nelore cattle BW. The patterns in these results lead to a revision of the importance of sexual and developmental factors on plasticity and adaptation concepts. 相似文献