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排序方式: 共有114条查询结果,搜索用时 13 毫秒
81.
This experimental study compares the efficiency of two fenestrated balloon catheters in allowing drainage of fluid during abdominal lavage in 12 healthy horses. Catheter A (with multiple side holes) or catheter B (with a single side hole) was placed in the ventral abdominal wall. Lactated Ringer's solution was instilled through a catheter in each paralumbar fossa of the standing horse. Drainage was performed through two catheters A in group 1, one catheter A in group 2, and one catheter B in group 3. Drainage was not significantly faster when using two, as compared with one, catheters A (P = 1). Amount of fluids recovered was greater using catheter A compared with catheter B (P = .004). Abdominal fluid analysis on day 30 was significantly higher (P = .008) for total protein in individuals with catheter B compared with catheter A. Use of one multiple fenestrated balloon catheter may be justified in clinical cases that need abdominal lavage and drainage.  相似文献   
82.
This study seeks to verify the perceptions of male and female respondents on the meaning and causes of success or failure in tree planting in public spaces and whether the specific projects were successful or failures. This was verified because the meaning and causes of success or failure in tree planting and whether a project is a success may have different meanings to different people in different parts of the world. This evaluation is motivated by the rising rates of tree planting failures recorded in Cameroon. Data were obtained through a focus group discussion, interviews with key informants, researcher’s observations and a survey. Statistical testing revealed that a major factor in success in tree planting is the active involvement of all stakeholders in the design, elaboration and implementation of the projects. A further factor is the diversification of livelihoods; when livelihoods are diversified the indigenes tend to have alternative income sources and reduced dependence on trees. To most respondents, the main criterion for judging success of a project is that trees grow to harvest age or become fully established.  相似文献   
83.
Advances in the understanding of guttural pouch physiology and novel therapeutic approaches to mycotic infections in the horse are reviewed. It is suggested that the guttural pouches may contribute to the regulation of arterial blood temperature, cooling the circulation to the brain to below body temperature. Aspergillus spp. is the major organism found in a guttural pouch affected with mycosis but it is unclear why this agent becomes aggressive. Conventional therapy aims to prevent fatal haemorrhage and to treat any neurological lesions but it is desirable to try to prevent the disease. A technique consisting of inserting a transarterial coil into the internal carotid, external carotid and maxillary arteries in normal and affected horses has been reported to be rapid, safe and effective in occluding the arteries and in inducing regression of the mycotic lesions without adjunctive medical treatment. When faced with acute and uncontrollable epistaxis in the field, the most effective means to reduce haemorrhage is probably the occlusion of both common carotid arteries. However, how such arterial occlusions can result in the successful management of guttural pouch mycosis without antifungal medication remains a mystery.  相似文献   
84.
REASON FOR PERFORMING STUDY: Diagnosis of osteochondrosis (OC) is based on clinical signs and radiography, but alternative methods for detection at an early stage would be useful. OBJECTIVES: To determine in the juvenile horse the relationship between serum concentrations of a number of biomarkers that reflect changes in cartilage and bone turnover and age, feeding level, growth, and the occurrence of OC. METHODS: Foals were assigned to a high (n = 20) or moderate (n = 19) feeding level group from birth to age 1 year. Bodyweight, withers height and cannon width were measured. Osteoarticular status was assessed radiographically at 5.5 and 11 months in all foals, and by necropsy at 12 months for 8 foals/group. Serum biomarkers of bone (osteocalcin, CTX-1) and cartilage (CPII, C2C) metabolism were assayed at 8 time points between ages 2 and 52 weeks. Ratios between biomarkers of tissue formation and degradation were calculated at each time point. RESULTS: Consistent age-related patterns in biomarker serum concentrates were found, indicating a markedly higher metabolism before age 20 weeks but concentrations were not affected by feeding level. Bodyweight was correlated negatively to C2C and CTX-1, and withers height was positively correlated to osteocalcin and the osteocalcin/CTX-1 and CPII/ C2C ratios. Osteocalcin concentration at 2 weeks and CPII/ C2C ratio at 20 weeks had strong positive correlations to OC, as diagnosed radiographically at 5.5 months. Osteocalcin had a strong correlation with radiographically detected OC at 11 months but at that time there was no significant relationship between CPII/C2C ratio and OC. CONCLUSIONS: Occurrence of OC lesions is significantly associated with anabolic changes in bone metabolism during the first weeks post partum, given the strong relation with osteocalcin. POTENTIAL RELEVANCE: Measuring osteocalcin concentrations during the first few weeks post partum may have potential value for the prediction of risk for OC development.  相似文献   
85.
The purpose of the study was to determine whether there were circadian variations in serum osteocalcin in normal horses and to determine whether it was important to regulate the time of blood sampling in clinical investigations. Osteocalcin or bone Gla-protein (BGP), alkaline phosphatase, total calcium, phosphate and total protein were studied over a 24 h period. Blood samples were taken every 60 min from nine adult Standardbred horses. There was a correlation between serum levels of alkaline phosphatase (r = 0.3, p less than 0.01), phosphate (r = 0.42, p less than 0.01) and serum osteocalcin levels. There was a very marked individual effect on serum levels of osteocalcin and alkaline phosphatase (p less than 0.01). This effect was present for phosphate levels but not significant for total calcium. The individual effect was lower and time effect was higher for serum osteocalcin if the subjects were divided into two age groups, one of horses of five years or less (n = 4) and a second group older than five years (n = 5). In both groups a circadian rhythmicity was observed. Serum osteocalcin showed a biphasic pattern. Levels were constant during daytime (light period) and underwent significant variations during the night (dark period), going through a nadir at 2000 h and through a maximum peak at 0500 h. It was concluded that in normal horses the blood osteocalcin level follows a circadian variation. Also daytime (light period) seems to be the more appropriate period for blood sampling.  相似文献   
86.
Conventional fluid resuscitation is unsatisfactory in a small percentage of equine emergency surgical cases because the large volumes of fluids required cannot be given rapidly enough to adequately stabilize the horse. In anesthetized horses, the volume expansion and cardiopulmonary effects of a small volume of highly concentrated hypertonic saline-dextran solution were evaluated as an alternative initial fluid choice. Seven halothane-anesthetized, laterally recumbent, spontaneously ventilating, normovolemic horses were treated with a 25% NaCl-24% dextran 70 solution (HSD) at a dosage of 1.0 ml/kg of body weight, IV, infused over 10 minutes, and the effects were measured for 120 minutes after infusion. Plasma volume expansion was rapid and significant (from 36.6 +/- 4.6 ml/kg to 44.9 +/- 4.8 ml/kg), and remained significantly expanded for the duration of the experiment. Packed cell volume, total blood hemoglobin, and plasma protein concentrations significantly decreased, confirming rapid and sustained volume expansion with hemodilution. Cardiac index and stroke index immediately increased and remained high for the entire study (from 69.6 +/- 15.3 ml/min/kg to 106.6 +/- 28.4 ml/min/kg, and from 1.88 +/- 0.49 ml/beat/kg to 2.50 +/- 0.72 ml/beat/kg, respectively). Systemic vascular resistance significantly decreased immediately after HSD infusion and remained decreased for the duration of the study (from 1.41 +/- 0.45 mm of Hg/ml/min/kg to 0.88 +/- 0.22 mm of Hg/ml/min/kg). Arterial and venous blood oxygen content decreased significantly because of hemodilution, but actual oxygen transport transiently increased at the 10-minute measurement before returning toward baseline.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
87.
OBJECTIVE: To evaluate the usefulness of multisite quantitative ultrasonography for noninvasive assessment of bone in horses. SAMPLE POPULATION: 12 healthy horses and both forelimbs from 8 clinically normal horses. PROCEDURE: For in vivo measurements, various regions of interest (ROI) were examined on the third metacarpal bone, radius, and tibia. Precision error for speed of sound (SOS) measurements was obtained by measuring each ROI of 4 horses 10 times with probe repositioning. Additionally, 3 operators measured each aspect of the third metacarpal bone of 6 horses 5 times each. For ex vivo measurements, third metacarpal bones were examined at 9 ROI, and SOS measurements were performed before and after soft tissue removal. One ROI of a single forelimb was subjected to 96 ex vivo measurements with 3 different contact media. RESULTS: The lateral aspect of the third metacarpal bone had significantly higher SOS values than the dorsal and medial aspect of the third metacarpal bone. No difference was obtained between SOS values of the lateral and medial aspect of the radius. The tibia had significantly higher SOS values than the lateral aspect of the radius and the dorsal and medial aspect of the third metacarpal bone. Intraoperator coefficients of variation ranged from 0.62 to 3.15%, and interoperator coefficients of variation ranged from 0.78 to 2.70%. Values of SOS were highest when silicone oil was used as the contact medium. CONCLUSIONS AND CLINICAL RELEVANCE: Speed of sound measurements obtained by quantitative ultrasonography in axial transmission mode can be used to precisely measure superficial cortical bone properties of third metacarpal bone, radius, and tibia in horses.  相似文献   
88.
This study reports on the effective use of a single transphyseal screw for the treatment of moderate to severe angular limb deformities (ALDs) of the fetlocks and carpi of 28 young Thoroughbred foals. The objective was to evaluate the surgical management of foals with moderate to severe ALDs treated with single transphyseal screws. Evaluation of medical records of 28 Thoroughbred foals treated with single transphyseal screws placed across the distal radial, metacarpal and metatarsal physes was undertaken. The angle of joint deviation was measured prior to implantation and at removal of the implants, and the degree of improvement was calculated. A total of 39 screws were placed: 24 in the distal metacarpus or metatarsus and 15 in the distal radial physis. Varus or valgus deformities in the fetlock improved by 4–5° over a period of 15–30 days. Varus or valgus deformities in the carpi improved by 8–11° in 11–56 days. One case failed to improve adequately due to implant infection. Single transphyseal screws were effective in treating moderate to severe varus and valgus ALD of the fetlocks and carpi in young Thoroughbred foals. Further investigation into their use in the distal radius in young foals is needed. While single transphyseal screws are almost exclusively used by some clinics in the distal metatarsal and metacarpal physes, many clinicians do not use them in the distal radial physis of young foals due to fear of over‐correction, physitis and metaphyseal collapse. This was not observed in any of our cases.  相似文献   
89.
Interleukin 4 (IL-4) is expected to play a dominant role in the development of T helper (Th) 2 cells. Th2 immune responses with expression of relatively large amounts of interleukin 4 (IL-4) but little interferon gamma (IFN-gamma) are characteristic for chronic helminth infections. But no information is available about IL4 expression during early Fasciola hepatica (F. hepatica) infections in cattle. Therefore, we investigated F. hepatica specific IL-4 and IFN-gamma mRNA expression in peripheral blood mononuclear cells (PBMCs) from calves experimentally infected with F. hepatica. Cells were collected prior to infection and on post-inoculation days (PIDs) 10, 28 and 70. Interestingly, PBMCs responded to stimulation with F. hepatica secretory-excretory products (FhSEP) already on PID 10 and expressed high amounts of IL-4 but not of IFN-gamma mRNA suggesting that F. hepatica induced a Th2 biased early immune response which was not restricted to the site of infection. Later in infection IL-4 mRNA expression decreased whereas IFN-gamma mRNA expression increased slightly. Isolated lymph node cells (LNCs) stimulated with FhSEP and, even more importantly, non-stimulated LN tissue samples indicated highly polarized Th2 type immune responses in the draining (hepatic) lymph node, but not in the retropharyngeal lymph node. During preliminary experiments, two splice variants of bovine IL-4 mRNA, boIL-4delta2 and boIL-4delta3, were detected. Since a human IL-4delta2 was assumed to act as competitive inhibitor of IL-4, it was important to know whether expression of these splice variants of bovine IL-4 have a regulatory function during an immune response to infection with F. hepatica. Indeed, IL-4 splice variants could be detected in a number of samples, but quantitative analysis did not yield any clue to their function. Therefore, the significance of bovine IL-4 splice variants remains to be determined.  相似文献   
90.
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