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61.
L-精氨酸对肺动脉高压肉鸡肺小动脉平滑肌细胞凋亡的影响 总被引:5,自引:1,他引:4
将240羽14日龄艾维茵-2000商品代肉鸡于14d时随机等分为常温对照组(NT组),低温组(LT组)和低温加L-精氨酸组(LA),白14d起,LT和LA组舍内温度从28℃以1~2℃/d的速度下降,至21d降至12~14℃,并维持到试验结束。此外,LA组自14d起在饲料中按100mg/kg剂量添加L—Arg,直至试验结束。记录肺动脉高压综合征(PHS)发病率,并分别于24、32、39和45d测定右心室/全心室质量比(RV/TV)、血浆NO、肺小动脉管壁面积/管总面积(WA/TA)和平均中膜厚度(mMTPA),并用原位缺口末端标记法(TUNEL法)对肺小动脉凋亡平滑肌细胞进行染色和计数。结果:LT组肉鸡PHS发病率、RV/TV、mMTPA和WA/TA值较NT组升高(P〈0.05);LA组肉鸡PHS发病率较LT组降低(P〈0.05),mMTPA和WA/TA值与LT组相比呈下降趋势,在32d时显著降低(P〈0.05);LT组血浆N0浓度总体上与NT组差异不显著(P〉0.05),仅在39d时降低(P〈0.05),而LA组血浆N0浓度自32d时起较NT和LT组显著升高(P〈0.05);LA组肉鸡肺小动脉平滑肌凋亡细胞百分率较NT组和LT组均显著升高(P〈0.05),但LT组与NT组之间相比无显著差异(P〉0.05)。上述结果表明,L-Arg/NO通过促进肺小动脉平滑肌细胞凋亡,从而在一定程度上抑制了肺血管重构的形成。 相似文献
62.
Thoracic radiographs of 21 dogs with necropsy-confirmed pulmonary thrombosis or embolism (PTE) were reviewed. Two major lung patterns were seen: (1) regional oligemia, giving the impression of a hyperlucent zone; (2) alveolar pulmonary infiltrate, indicating hemorrhage or infarction. Hemorrhage and infarction could not be differentiated radiographically. Other common findings were attenuation or loss of visualization of a lobar artery or lobar vein and pleural effusion, particularly with infarction and cardiac disease. PTE was often associated with renal disease (glomerulonephritis, amyloidosis), septic processes, pancreatitis, systemic venous or right heart thrombosis, cardiac insufficiency, and hypercorticism. 相似文献
63.
Jarod E. Williams DVM Susan G. Hackner BVSc MRCVS DACVIM DACVECC 《Journal of Veterinary Emergency and Critical Care》2001,11(3):221-227
Objective: This report describes the perioperative management of a dog with a right adrenal pheochromocytoma that presented with acute retroperitoneal hemorrhage, cardiac arrhythmia and hypertension. Additionally, a summary of pheochromocytoma and the idiosyncrasies of perioperative management of a pheochromocytoma are provided.
Summary: A 7-year old male, neutered, Dalmation was presented for acute collapse, abdominal pain and tachycardia. Physical examination findings were consistent with hypoperfusion concurrent with multiple cardiac arrhythmias and hypertension. Abdominal ultrasound revealed retroperitoneal effusion and a right adrenal mass intimately associated with the caudal vena cava. Incomplete right adrenalectomy was performed. Histopathology confirmed a pheochromocytoma.
Unique information provided: To the authors' knowledge, this is the first definitive report of acute retroperitoneal hemorrhage as the initial clinical manifestation of histologically confirmed adrenal pheochromocytoma in the dog. ( J. Vet Emerg Crit Care 2001; 11(3): 221–227 ) 相似文献
Summary: A 7-year old male, neutered, Dalmation was presented for acute collapse, abdominal pain and tachycardia. Physical examination findings were consistent with hypoperfusion concurrent with multiple cardiac arrhythmias and hypertension. Abdominal ultrasound revealed retroperitoneal effusion and a right adrenal mass intimately associated with the caudal vena cava. Incomplete right adrenalectomy was performed. Histopathology confirmed a pheochromocytoma.
Unique information provided: To the authors' knowledge, this is the first definitive report of acute retroperitoneal hemorrhage as the initial clinical manifestation of histologically confirmed adrenal pheochromocytoma in the dog. ( J. Vet Emerg Crit Care 2001; 11(3): 221–227 ) 相似文献
64.
John R. Pascoe BVSc Timothy R. O'Brien DVM PhD John D. Wheat DVM Dennis M. Meagher DVM PhD 《Veterinary radiology & ultrasound》1983,24(2):85-92
Abnormal pulmonary radiopacities were identified in 13 racing horses in which a diagnosis of exercise-induced pulmonary hemorrhage (EIPH) had been confirmed. The lesions were in the caudal lung lobe in all horses; seven were on the right and three on the left, and the laterality for three could not be determined. In ten horses the opacities, which were large and peripherally located, obliterated the thoracophrenic angle. They merged with the silhouette of the diaphragm and had a circular or ovoid surface directed toward the hilum. The intensity of opacification of the consolidated areas varied, and they often were not sharply marginated. Dorsal displacement of the pulmonary arteries was noted in the region of the radiopacity in seven horses. Varying volumes of pleural effusion were observed in nine horses. Serial radiographic examinations were performed in seven horses. The pulmonary radiopacities cleared within ten days in two horses. In the remaining five horses, gradual resolution, characterized by a reduction in lesion size with improved margination, occurred during several months. The central region of the radiopaque lesion commonly had a patchy appearance, suggesting cavitation. Normal pulmonary vascular and interstitial markings were evident following complete resolution of these lesions. The cause of these abnormal pulmonary opacities has not been determined. Pathologic-radiologic correlations will be required to improve understanding of the pathophysiology of EIPH in the racing horse. 相似文献
65.
DeHeer HL McManus P 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(1):17-22
BACKGROUND: Hemosiderophages may be found in feline tracheal wash specimens in association with various disease conditions, including heart failure, trauma, infection, foreign body migration, lung lobe torsion, pulmonary embolism or infarction, neoplasia, and bleeding diathesis. Based on observations in our laboratory, we hypothesized that tracheal wash specimens from cats with asthma also frequently contain hemosiderophages, even in the absence of other known causes of pulmonary hemorrhage. OBJECTIVES: The purpose of this study was to determine the frequency and severity of hemosiderosis in tracheal wash fluid from cats with various diseases, including asthma. METHODS: Feline tracheal wash fluid specimens submitted for cytologic evaluation between March 2002 and August 2003 were included in the study. One hundred and one specimens from 96 cats were examined with both Wright's-Giemsa and Prussian blue stains. Cats were assigned to 6 disease categories: feline asthma, pneumonia, pulmonary neoplasia, rhinitis, heart disease, and other disorders. Based on the percentage of Prussian blue-positive macrophages, hemosiderosis was categorized as negative (0%), mild (<20%), moderate (21-50%), or marked (>50%). RESULTS: The frequency of tracheal wash hemosiderosis in the study population was 63.5% (61/96); hemosiderosis was mild (29/96, 30.2%), moderate (22/96, 22.9%), or marked (10/96, 10.4%). Hemosiderosis was found in 85.7% (6/7) of cats with rhinitis, 78.6% (11/14) of cats with pulmonary neoplasia, 75.0% (27/36) of cats with asthma, 71.4% (5/7) of cats with primary or concurrent heart disease, 25.0% (5/20) of cats with pneumonia, and 66.7% (12/18) of cats with other disorders. In cats with asthma, hemosiderosis was usually mild to moderate and frequently was accompanied by increased eosinophils. CONCLUSIONS: The results of this study confirm that hemosiderosis is a common finding in tracheal wash specimens collected from cats with diverse disease conditions, including feline asthma syndrome. 相似文献
66.
La Croix NC 《Clinical Techniques in Small Animal Practice》2005,20(2):121-128
Systemic feline diseases (parasitic, bacterial, fungal, viral, neoplastic, metabolic, vascular, and immune-mediated) are often associated with ocular symptoms. An ocular examination is an important diagnostic tool and should be part of any physical examination. Conversely, cats afflicted with systemic disease require periodic ocular examinations for prognostic information and to prevent vision threatening complications. Typical feline systemic diseases encountered by the practicing clinician are presented with their commonly associated ocular signs. 相似文献
67.
Senior M 《Veterinary anaesthesia and analgesia》2005,32(4):193-200
OBJECTIVES: To review information on the pathogenesis, diagnosis and treatment of post-anaesthetic pulmonary oedema in horses. DATABASES USED: Pubmed 1970-present, personal files. 相似文献
68.
Wilkins PA Boston R Palmer JE Armstead WM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(4):594-598
Increased endothelin-1 (ET-1) plasma concentration in human infants is associated with persistent pulmonary hypertension of the newborn, a problem also identified in calves derived from somatic cell clone technology. Increased ET-1 also is present in the amnionic fluid and plasma of the infant and mother in preeclampsia, a condition associated with abnormal placentation. Abnormalities in placentation are identified in clone calves. We measured ET-1 in fetal fluid, calf plasma, and surrogate dam plasma in 40 clone calves at the time of term delivery. Calves were subsequently identified as being either oxygen treated (O2) or non-oxygen treated based on their postpartum clinical course. Fetal fluid ET-1 concentration greater than 1.4 ng/mL carried a 3-fold increase in odds of the calf being treated with oxygen. Maternal plasma ET-1 concentration was greater in the O2 group (13 pg/ mL: [8-23 pg/mL] versus 25 pg/mL [12-40 pg/mL]; median, 25-75 percentile). Plasma ET-1 concentration in calves was not significantly different between groups. Fetal fluid ET-1 may serve as a marker for neonatal disorders of oxygenation in clone calves and the source of ET-1 may be the placenta. 相似文献
69.
Objective To evaluate the effect of topical ophthalmic 10% phenylephrine on systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), pulse rate (PR) and electrocardiogram (ECG) in dogs. Animals studied Nine clinically normal dogs. Procedure Arterial catheters were placed in the dorsal pedal artery of awake dogs and ECG leads were attached. After a 15‐min acclimatization period, baseline PR, SAP, DAP and MAP were recorded every 5 min for 20 min. Two treatment groups (eight dogs each) were studied. Group I: one drop of phenylephrine was placed in each eye once. Group II: one drop of phenylephrine was placed in each eye three times at 5‐min intervals. Following treatment, PR, SAP, DAP and MAP were recorded every 5 min for 90 min. The mixed procedure of the SAS system was used to perform a repeated measures analysis of variance to test for linear and quadratic trends across time. Results Group I: There was a significant quadratic decrease in PR across time (P = 0.0051). Systolic arterial pressure increased linearly with time (P = 0.0002), MAP increased linearly with time (P = 0.0131), and DAP increased linearly with time (P = 0.0001). Group II: There was a significant quadratic decrease in PR across time (P = 0.0023). There was a significant quadratic increase in SAP (P = 0.0324), MAP (P = 0.0103) and DAP (P = 0.0131) across time. Conclusions Topical ophthalmic application of 10% phenylephrine in normal dogs results in elevation of arterial blood pressure and reflex bradycardia. 相似文献
70.
Time-specific intraocular pressure curves in Rhesus macaques (Macaca mulatta) with laser-induced ocular hypertension 总被引:1,自引:0,他引:1
Ollivier FJ Brooks DE Kallberg ME Sapp HL Komáromy AM Stevens GR Dawson WW Sherwood MB Lambrou GN 《Veterinary ophthalmology》2004,7(1):23-27
Objective To detect and categorize time‐specific variations in daytime intraocular pressure (IOP) found in Rhesus monkeys with laser‐induced ocular hypertension. Procedures Ten male monkeys with argon laser‐induced ocular hypertension in one eye were anesthetized with ketamine hydrochloride, and the IOP measured in both eyes at 7 a.m., 7.30 a.m., and then hourly until 1 p.m. with a Tonopen? XL applanation tonometer. Intraocular pressure time profiles for both eyes in each animal were developed. The means ± SD of the IOPs for both eyes were calculated for the whole 6‐h study period, and the values compared statistically. The difference between the lasered eye mean IOP standard deviation and the normal eye mean IOP standard deviation for each animal during the 6‐h follow‐up was also calculated and compared. Results Mean IOP (± SD) in the glaucoma and normal eyes for the 10 animals during the 6‐h study was 32.6 ± 2.5 and 14.9 ± 2.5 mmHg, respectively. The IOP was significantly higher in the experimental eye than in the normal eye (P = 0.0008). The mean IOP in the lasered eye did not significantly change during the study period, whereas a slight but significant increase in IOP of the normal eye over the study period was recorded (P = 0.003). The variance in IOP in the hypertensive eyes was considerably greater than that in the untreated control eyes. From 7 a.m. to 1 p.m. the IOP declined in five eyes and increased in the other five eyes with laser‐induced ocular hypertension. Conclusions The time‐specific IOP variation pattern in the daytime in the laser treated eyes is significantly greater than the variation in the normotensive eyes. This shows that in order to detect statistical differences between IOP variations induced by an IOP‐reducing drug, and the exaggerated spontaneous IOP variations present in the laser‐induced hypertensive eye, sufficient animals should be included in any study. Understanding the time‐specific IOP variation present in a group of monkeys with laser‐induced ocular hypertension is essential prior to using the model for the evaluation of IOP‐reducing drugs. 相似文献