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151.
152.
We evaluated the long-term effect of early angiotensin-converting enzyme (ACE) inhibition (enalapril maleate) as monotherapy to postpone or prevent congestive heart failure (CHF) in asymptomatic dogs with mitral regurgitation (MR) attributable to myxomatous valvular disease (MVD) in a prospective, randomized, double-blinded, placebo-controlled multicenter trial involving 14 centers in Scandinavia. Two hundred twenty-nine Cavalier King Charles (CKC) Spaniels with MR attributable to MVD but no signs of CHF were randomly allocated to treatment with enalapril 0.25-0.5 mg daily (n = 116) or to placebo groups (n = 113). Each dog was evaluated by physical examination, electrocardiography, and thoracic radiography at entry and every 12 months (+/-30 days). The number of dogs developing heart failure was similar in the treatment and placebo groups (n = 50 [43%] and n = 48 [42%], respectively; P = .99). The estimated means, adjusted for censored observations, for the period from initiation of therapy to heart failure were 1,150 +/- 50 days for dogs in the treatment group and 1,130 +/- 50 days for dogs in the placebo group (P = .85). When absence or presence of cardiomegaly at the entrance of the trial was considered, there were still no differences between the treatment and placebo groups (P = .98 and .51, respectively). Multivariate analysis showed that enalapril had no significant effect on the time from initiation of therapy to heart failure (P = .86). Long-term treatment with enalapril in asymptomatic dogs with MVD and MR did not delay the onset of heart failure regardless of whether or not cardiomegaly was present at initiation of the study.  相似文献   
153.
A 13-year-old male Setter-Springer crossbred dog was presented with signs of acute peritonitis three days after blunt abdominal trauma. In abdominal radiographs, a bubbly accumulation of gas in the central and cranioventral parts of the liver silhouette and mild peritoneal effusion were seen. At laparatomy, firm, necrotic, nodular hepatic masses containing gas were found to be ruptured. The histologic diagnoses were hepatic adenoma with hepatic necrosis and nodular hepatic hyperplasia. The pathogenesis of hepatic abscessation and the radiographic differential diagnosis of extraluminal abdominal gas are discussed.  相似文献   
154.
155.
The penetration of insecticides into houseflies, with and without the factor that delays penetration, was studied by measuring the amounts of the insecticides on the surface of the flies at intervals after treatment. The factor slowed the entry of all the insecticides tested, but its effect depended on the dose, and had little or no effect when the dose applied was big (20 μmUg/fiy). Penetration in all strains, susceptible and resistant, increased but not proportionally to the size of the dose. The rate insecticide was lost from the surface slowed with time and increasing age of the insects. It was faster in males than females, and was always faster in flies without the penetration factor. The differences in penetration between the flies with and without the factor was less with n-dodecane as solvent than with acetone. With all strains, rate of loss from the surface was slowest with dieldrin. Diazinon, parathion and chlorthion-ethyl were lost at about the same rate; diazoxon penetrated fastest.  相似文献   
156.
Six 3‐year‐old goats (three males and three females) weighing 60.0 ± 18 kg (mean ± SD) were used to investigate the effect of medetomidine (MED; 20 µg kg?1 IV) and its antagonism with atipamezole (ATI; 100 µg kg?1 IV) on physiologic responses (heart rate (HR; beats minute?1), respiratory rate (RR; breaths minute?1), electrocardiogram (ECG), rectal temperature (T; °C), blood pressure (oscillometric; mm Hg), sedation (SED), posture (REC), analgesia (ALG), and stress‐related hormonal and metabolic responses (epinephrine and norepinephrine (high performance liquid chromatography with electrochemical detection), cortisol (COR; µg dL?1; radioimmunoassay), glucose (GLU; mg mL?1; enzymatic colorimetric assay), and free fatty acids (modified enzymatic colorimetric assay)); each goat received ATI or SAL in random order separated by 1 week. Jugular catheters were placed for drug administration and blood sampling (10–12 mL sample?1) using a lidocaine skin block (20 mg) 2 hours prior to beginning of each trial; during this trial, goats breathed room air. Physiologic parameters were measured, SED, REC, and ALG were scored, and blood samples were collected from jugular catheters at baseline (time = ?30 minutes), 5 minutes post‐MED administration (time = ?25 minutes), 25 minute post‐MED administration and immediately prior to antagonism (time = 0 minute), and at 5, 30, 60, and 120 minutes after administering ATI or SAL. ALG was tested by clamping the withers and metacarpus with hoof testers fitted with a force transducer to measure applied isometric force (lb) (a technique used previously in goats to evaluate analgesia). Continuous variables were analyzed by Repeated Measures analysis of variance (anova ); categorical data were analyzed using a Friedman Repeated Measures anova on ranks. A p‐value of <0.05 was considered significant. If a significant difference was found, a Dunnett's pair‐wise comparison of means was conducted. Differences between ATI and SAL were examined at 5, 30, 60, and 120 minutes using a paired t‐test with a Bonferroni correction. Administration of MED resulted in a decrease in T (38.7 ± 0.3 to 34.5 ± 0.4 °C), HR (78 ± 19 to 55 ± 9), and RR (31 ± 12 to 14 ± 5) over time; an increase in mean arterial blood pressure (90 ± 19 to 132 ± 23), COR (0.254 ± 0.125 to 4.327 ± 1.233), and GLU (82.0 ± 13.2 to 255.9 ± 38.9); and changes in SED (alert to marked sedation), REC (standing to recumbent), and ALG (metacarpus = 5 ± 2 to 14 ± 0; withers = 3 ± 2 to 14 ± 0). GLU was 62–70% higher at 60 and 120 minutes and COR was 336% higher after SAL than after ATI at 120 minutes; at 30, 60, and 120 minutes, T was 4–10% higher after ATI than SAL. There were no other significant differences. REC, SED, and ALG were antagonized after ATI. ATI did not antagonize the effect of MED on HR, RR, or MAP, but stabilized T and antagonized the increase in GLU and COR.  相似文献   
157.
158.
Osteopetrosis is a rare disorder characterised by a defect in osteoclastic bone resorption. This report describes osteopetrosis in a neonatal donkey that suffered a displaced tibial fracture. Radiographic examination identified generalised reduction in medullary cavity size, thickened mid‐diaphyseal cortices and conical metaphyseal bone extending toward the mid‐diaphysis of long bones. Postmortem examination identified additional fractures and brittle bones. Histologically, osteoclasts were absent in multiple bone sections. Diaphyseal cortices consisted of concentric bone lamellae with marrow tissue infiltration. Large wedges of secondary spongiosa extended from the metaphyseal growth plate. Clinical and histopathological features were similar to an osteoclast‐deficient, autosomal recessive form of osteopetrosis in humans.  相似文献   
159.
With the development of the non‐surgical deep uterine (NsDU) embryo transfer (ET) technology, the commercial applicability of ET in pigs is now possible. There are, nevertheless, many factors that influence NsDU‐ET effectiveness that need to be addressed. The aim of this study was to evaluate the effects of the weaned recipients' parity on fertility and prolificacy following NsDU‐ET. The recipients (n = 120) were selected based on their reproductive history and body condition and grouped into three categories according to their parity: primiparous sows, sows of parity 2 and sows of parities from 3 to 5. Thirty fresh embryos (morulae and unhatched blastocysts) were non‐surgically transferred into one uterine horn of each recipient. It was possible to insert the NsDU‐ET catheter through the cervix along a uterine horn in 98.3% of the recipients. The parity had no influence on the difficulty grade of the insertions or on the percentage of correct insertions. The cervix and uterine wall were not perforated during the insertions, and vaginal discharge was not observed after transfer in any of the recipients. There were no differences in the pregnancy rates (74.8%), farrowing rates (71.2%) or litter sizes (9.6 ± 3.3) between groups. Also, there were no differences between groups regarding to the piglets' birthweights or piglet production efficiency. In conclusion, these results demonstrate that weaned sows from parity 1 to 5 are appropriate to be used as recipients in NsDU‐ET programs, which increase the possibilities for the utilization of ET in the recipient farms.  相似文献   
160.
The aims of this study were to assess the effects of the sex‐sorting process on post‐thaw sperm quality as well as on induced oxidative stress damage (H2O2 0 mm  = H000; H2O2 50 mm  = H050; H2O2 100 mm  = H100) and the protective action of reduced glutathione (GSH) and Trolox, when comparing sorted (BSS) and non‐sorted (NS) red deer spermatozoa incubated at 37°C. Sperm samples from three stags were collected by electroejaculation and frozen. Immediately after thawing, sperm motility was higher (p < 0.05) for NS (59% ± 3.3) than BSS (36.9% ± 5.8) sperm. Furthermore, the percentage of apoptotic sperm was higher (p < 0.05) for BSS (21.6% ± 5.0) than NS sperm (14.6% ± 1.2). The presence of H2O2 increased DNA damage in NS (H000 = 4.1% ± 0.9; H050 = 9.3% ± 0.7; and H100 = 10.9% ± 2.3), but not in BSS sperm. However, in the presence of oxidant, GSH addition improved (p < 0.05) sperm motility in both groups of sperm samples as compared to their controls (NS: 44.5 ± 4.8 vs 21.1 ± 3.9 and BSS: 33.3 ± 8.1 vs 8.9 ± 1.8). These results demonstrate that the sperm‐sorting process induces sublethal effects, albeit selecting a sperm population with a chromatin more resistant to oxidative stress than that in non‐sorted sperm. Moreover, addition of GSH at 1 mm may be a good choice for maintaining the quality of stressed sperm samples, unlike Trolox, which inhibited sperm motility.  相似文献   
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