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Objective To determine the reliability of collecting serial 4-mL blood samples over 13 h using a 20-gauge, cephalic catheter in conscious dogs. Design Prospective, observational study. Animals Twelve (6 males, 6 females) healthy, neutered, lean dogs. Procedure Percutaneous placement of a 20-gauge, 1.1 × 30 mm intravenous over-the-needle catheter into the cephalic vein was performed in each dog on three occasions. Catheter patency was maintained by intermittent flushing with 0.9% saline and 1 IU/mL heparinised saline solutions. Blood samples (4 mL) were obtained at 10 time-points over 13 h, with close monitoring of the dogs and the indwelling catheters. Blood volume, resistance on aspirating blood sample (minimal or marked resistance) and the methods used to improve blood flow were recorded. Results A high proportion (93%) of blood sample collections achieved the required 4-mL volume, and the remaining samples were greater than 1.5 mL. Of the 358 collections via the cephalic catheter, 311 (87%) were obtained with ‘minimal resistance’. The remaining collections had ‘marked resistance’ (n=47) and were associated with a loose catheter in 11% (5/47) and of unknown cause in 89% (42/47). After ‘marked resistance’ had been encountered and the catheter was flushed with saline and heparin solutions, subsequent sampling with ‘minimal resistance’ was frequently possible from the same catheter. Conclusion Use of a percutaneous, 20-gauge intravenous cephalic catheter allowed reliable serial collection of 4-mL blood samples over 13 h in conscious dogs.  相似文献   
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The uterus plays an essential role in mammalian reproduction and is a target of several hormonal protocols used to improve fertility in cattle. Many studies highlighted the importance of eCG treatment following fixed‐time artificial insemination in improving follicular growth, ovulation and pregnancy rates in cattle. Moreover, eCG has been implicated in angiogenesis, leading to important changes in uterine blood flow and vascularisation. However, there is still a lack of information regarding the specific alterations induced by eCG upon glandular and vascular characteristics of bovine uterus. To investigate the influence of eCG on: uterine thickness and area; uterine artery diameter and area; uterine vascular and gland density; and the expression of the VEGFA‐system, the uteri of crossbred beef cows were collected. All cows were submitted to follicular wave emergence synchronization. On day four of protocol, cows submitted to superovulation (n = 6) received 2000 IU eCG, on day eight, after expected follicular deviation, cows submitted to stimulatory treatment (n = 5) received 400 IU eCG. Control cows (n = 5) did not receive eCG. On day five po cows were subjected to ultrassonographic evaluation and slaughtered for uterine tissue sampling on day six po. Uterine vessels and glands were quantified by the counting point stereological method. The VEGFA‐system was localized in different cellular types, showing no qualitative or quantitative differences in the site of expression or the intensity of the positive signal among the groups. Vascular density was decreased in the endometrium of stimulated and myometrium of superovulated cows compared with the control ones, which showed higher vascular density in the myometrium and endometrium of the ipsilateral uterine horn. The uterine gland density was higher in superovulated compared with stimulated and control cows. Thus, we can infer that stimulatory or superovulatory treatments with eCG influence the vascular density in the endometrium and myometrium in cattle.  相似文献   
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This report describes the diagnosis and treatment of vulvar papillomatosis with carcinoma in situ in a 25‐year‐old mare. Papillomavirus was demonstrated via immunohistochemical staining of biopsies of the lesion. The papillomas were removed via laser excision and the surrounding vulvar tissue injected with 5‐fluorouracil. Additional more extensive laser excisions were required due to recurrence.  相似文献   
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A methodology is developed for revealing and identifying genetically modified sources (GMSs) in plant raw material and food products obtained from it, which enables routine analyses. For optimization suitable for testing DNA, three methods of isolating it are compared: CTAB method, DNA-BioPro method with Wizard columns, and Silica M method with specific adsorbents. More than 400 food items from different populated areas of the Moscow region are analyzed.  相似文献   
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The atmospheres of Jupiter, Saturn, Uranus, and Neptune were modeled as shallow layers of turbulent fluid overlying a smooth, spherical interior. With only the observed values of radius, rotation rate, average wind velocity, and mean layer thickness as model parameters, bands and jets spontaneously emerged from random initial conditions. The number, width, and amplitude of the jets, as well as the dominance of anticyclonic vortices, are in good agreement with observations for all four planets.  相似文献   
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A yearling Arabian filly presented with a history of acute hindlimb lameness, marked tarsocrural effusion and associated soft tissue swelling and was diagnosed with fractures of both the lateral and medial malleoli of the distal aspect of the tibia. The fractures were repaired using a combination of cortical bone screws placed in lag fashion and a tension band wire. A full limb cast bandage was placed for recovery from general anaesthesia and the early post operative period. Despite radiographic development of osteoarthritis, 21 months after surgery the filly was clinically sound and racing successfully.  相似文献   
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