ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04383.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04384.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04385.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04386.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThe effects of oxytocin on the percentage of technetium99malbumin colloid (99mTc‐μAA), cleared from the uterine lumen was measured in 13 mares. Scintigraphy was performed during 4 consecutive oestrous cycles, on Day 3 of oestrus during Cycles one and 3 and 48 h after ovulation during Cycles 2 and 4. Oxytocin (20 iu) was given i.v. after the initial scintigraphy image during Cycles 3 and 4. Seven multiparous mares(Group 1)were classified as ‘susceptible’ and 6 mares (2 nulliparous and 4 multiparous;Group 2) were classified as ‘resistant’ to endometritis. All mares cleared>90% of99mTc‐μAA within 30 min of oxytocin injection. When no drug was given,Group 1mares cleared negligible amounts of radiocolloid (<5%) andGroup 2mares cleared 50–80%. No mares showed signs of colic after oxytocin administration. It is concluded that oxytocin enhances uterine clearance of radiocolloid and may be useful for treating mares exhibiting impaired ut

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04387.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryTo develop a bronchoscopic map of the equine respiratory tree, the major airways of the lungs of 6 healthy Thoroughbred horses were systematically explored with a flexible fibreoptic endoscope through a tracheostomy while the horses were sedated in stocks. With the carina as the reference point, measurements were made of distances to the branches of the major airways using markers on the shaft of the endoscope. All branches were explored until the narrowing of their diameters prevented further advancement of the endoscope. Positions of origins of branches from the parent bronchus were recorded in relation to a 12 h clock. Branching patterns of the right and left lungs were similar. Seventeen branches of the principal and caudal lobar bronchi of the left lung, and 18 branches of the principal and caudal lobar bronchi of the right lung were identified. Mean explorable distances from the carina to the ends of the right and left caudal lobar bronchi were 34.0 ± 3.5 (sd) and 34.5 ± 3.0 cm, respectively. Generally, smaller horses had shorter explorable bronchial lengths. Branching patterns of the parent bronchi were fairly consistent among horses, particularly the branches closest to the carina. After endoscopy and euthanasia, the lungs were removed, and dried with pressurised air flowing through them for 7–10 days. Attempts to explore the airways of the dried lungs endoscopically were relatively unsuccessful, because airways were much smaller in the dried lungs, and many of the branches were distorted when compared with their ante‐mortem appearances. However, having a dried lung specimen as a reference during the bronchoscopic procedure was useful for maintaining orientation in the lungs. Radiographs were used to estimate the location of the origin and destination of each airway branch in relation to the nearest intercostal space. This makes the airway map useful when lesions identified radiographically are to be la

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04388.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryDifferential scanning calorimetry (DSC) of equine superficial digital flexor tendons revealed the presence of a small exothermic peak at 23°C of unknown origin, and a large endothermic peak at 70°C due to denaturation of cross‐linked collagen fibres. In the central degenerated core of damaged tendons the denaturation temperature remained at 70°C but the enthalpy decreased in relation to the extent of degeneration of the tendon. We suggest that this reduction in enthalpy is due to depolymerisation and denaturation of the collagen fibres. This contention is supported by the observed increased activity of the degradative enzyme cathepsin B secreted by the fibroblasts. DSC analysis of cultured porcine tendon fibroblasts revealed a multicomponent endotherm, denaturation beginning at 46°C, a temperature capable of being achieved within the tendon during intensive exercise. DSC clearly has considerable potential in complementing morphological and biochemical studies to determine the aetiology and progress of equine tendon degener

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04389.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryThe effect of human recombinant interleukin‐1ß (rhIL‐1ß) on proteoglycan metabolism was investigated in cultures of full thickness explants of articular cartilage from horses 3–21 years of age. Proteoglycan synthesis was inhibited at all ages but no alteration in the hydrodynamic size or electrophoretic heterogeneity was observed in proteoglycan isolated from rhIL‐1ß stimulated cartilage. The sulphation pattern of the newly synthesised proteoglycan molecules was, however, significantly affected by the presence of the peptide regulatory factor. Interleukin‐1 had no effect on the rate of turnover of newly synthesised or endogenous proteoglycans in mature equine articular cartilage and did not influence the structure of proteoglycan fragments released into the culture medium. These observations suggest that IL‐1, released into synovial fluid during inflammation, may modify the proteoglycan composition of normal equine cartilage not by stimulating catabolic enzymes capable of degrading the resident proteoglycans but by promoting the deposition of a reduced number of newly synthesised proteoglycan molecules of abnorm

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04390.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryIn the foot of the horse, arteriovenous anastomoses (AVAs) of epithelioid type occurred in the dermis of the coronary band, in the coronary and terminal papillae, in neurovascular bundles and at the entrance to and along the length of the dermal laminae. A particular feature of the epithelioid segment of AVAs in the horse, compared with that of other species, was the height and surface complexity of many of the endothelial cells. They extended into the lumen, forming undercut and tunnel‐like areas which correlated with the characteristic surface marking of AVAs observed in vascular casts. The number of cell organelles, including the concentration of vesicles in the luminal cytoplasm, suggested cells with a high metabolic activity. The luminal surface possessed numerous microvilli and long cytoplasmic cell processes which appeared to surround material in the lumen.The innervation of AVAs was more dense than that of the arteries and consisted of adrenergic and peptidergic nerves. Noradrenaline‐ and neuropeptide Y‐containing nerves were identified as the vasoconstrictor components of the nerve supply and occurred along arteries and formed dense plexuses around AVAs. Calcitonin gene‐related peptide, substance P and vasoactive intestinal polypeptide are vasodilators and were present in single nerve fibres which accompanied arteries and AVAs along the length of the dermal laminae. In this study the distribution, density and innervation of AVAs in the equine foot are correlated with their proposed role in the development of acute laminitis. The release of vasoactive peptides from diseased organs remote from the foot may induce inappropriate prolonged dilatation of AVAs and thus contribute to the laminar ischaemia of acute la

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04391.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

SummaryFive Thoroughbred and Quarter Horse cross foals were given 20 μg canine recombinant granulocyte‐colony stimulating factor (rcG‐CSF) per kg bwt intramuscularly (i.m.) on the day of birth and 10 μg rcG‐CSF/kg for 13 additional days. During this time and for an additional 21 days haematology, bone marrow and clinical chemical analyses were performed. After one day of rcG‐CSF administration leucocyte and neutrophil counts increased from 9.16 × 109/1 to 23.44 × 109/1 and from 6.45 × 109/1 to 19.61 × 109/1, respectively. The counts continued to increase for the next 3–4 days and then there was a slight decrease. A second increase followed and the leucocyte and neutrophil counts increased to 52.84 × 109/1 and 45.16 × 109/1 on the day after the last rcG‐CSF administration (Day 15). The counts decreased rapidly immediately after the administration of rcG‐CSF was stopped and then at a slower rate. The cell counts were still higher than in the controls at the end of the study period (Day 35). Bone marrow cellularity increased from 10–25% before rcG‐CSF was given to 60–80% after 5 days. The increase in cellularity was due to increased myeloid activity because the myeloid to erythroid ratio increased from 2.7 to 8.8. Serum chemistry changes were minimal although foals given rcG‐CSF at various times had lower glucose concentrations and increased alkaline phosphatase and gamma gl

ISSN:0425-1644    

DOI:10.1111/j.2042-3306.1994.tb04392.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY