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1.
Three dogs were presented to us for evaluation of cardiac problems. Electrocardiographic recordings revealed severe tachyarrhythmia and atrial fibrillation with ventricular tachycardia in 2 of the 3 dogs. The echocardiographic findings of the 3 dogs revealed markedly decreased fractional shortening and a marked increase in E-point septal separation. Based on the results of electrocardiographic and echocardiographic evaluation, the 3 dogs were diagnosed as dilated cardiomyopathy (DCM). The dogs were treated with conventional cardiac medication, but cardiac function did not improve and the clinical signs remained. We subsequently attempted treatment with granulocyte-colony stimulating factor (G-CSF; 10 microg/kg, subcutaneously). The specific purpose of G-CSF therapy for DCM was to improve cardiac function and a significant improvement in cardiac function was confirmed. The three dogs had no treatment side effects. This case report suggests that G-CSF might have therapeutic effects for medically refractory DCM in dogs.  相似文献   
2.
Heat stress has detrimental effects on lactating sows and their litters, including decreased feed intake and milk production in sows and decreased weight gain in their offspring. It also increases respiration rate, rectal temperature, and weaning to estrus interval in sows. This study was conducted to investigate the effects of chilled water (CW) on the performance of lactating sows and their litters exposed to high ambient temperatures for 21 days. Ninety multiparous sows (Yorkshire × Landrace; parity range: 2 to 5) and their litters (Yorkshire × Landrace × Duroc) were divided into 3 blocks (30 each). Sows and their litters within each block were randomly assigned to one of the three treatment groups (n = 10 each). Each group was provided with drinking water at 10, 15, or 22 °C (control) under farm conditions where ambient temperature above 25 °C was consistent during the experimental period. Sows on CW (both 10 and 15 °C) consumed more feed and water than did control (P < 0.01) and higher estimated milk production compared with control (P < 0.01), but had lower rectal temperature and respiration rate compared with control (P < 0.01). Mean weaning weight (P < 0.01) and average daily gain (P < 0.01) of litters in CW groups were higher than those in control group. There were no differences in the measured variables, with the exception of the respiration rates, between the two CW treatment groups. These results suggest that CW may improve the performance of sows and their litters exposed to high ambient temperatures and the 15 °C water, from an energy viewpoint, may be more effective.  相似文献   
3.
The aim of the present study was to assess the clinical and histopathological findings in a canine model of ischemic stroke. Cerebral ischemic stroke was induced by middle cerebral artery occlusion in four healthy beagle dogs using silicone plugs. They showed neurological signs of forebrain dysfunction such as reduced responsiveness, head turning, circling, postural reaction deficits, perceptual deficits, and hemianopsia. These signs gradually regressed within 4 weeks without therapy. On magnetic resonance imaging, T2 hyperintensity and T1 hypointensity were found in the cerebral cortex and basal ganglia. These lesions were well-defined and sharply demarcated from adjacent brain parenchyma with a homogenous appearance. No abnormalities of the cerebrospinal fluid were observed. At necropsy, atrophic and necrotic lesions were observed in the cerebral cortex. The cerebral cortex, basal ganglia, and thalamus were partially unstained with triphenyl-tetrazolium chloride. Histopathologically, typical features of infarction were identified in cortical and thalamic lesions. This study demonstrates that our canine model resembles the conditions of real stroke patients.  相似文献   
4.
Thyroid disease is common in dogs and conventional ultrasonography is a standard diagnostic test for diagnosis and treatment planning. Strain elastography can provide additional information about tissue stiffness noninvasively after applying external or internal compression. However, natural carotid artery pulsations in the canine thyroid gland are too weak to maintain sufficient internal compression force. The objective of the present study was to describe the feasibility of strain elastography for evaluating the canine thyroid gland and the repeatability of dobutamine‐induced carotid artery pulsation as an internal compression method. In seven healthy Beagle dogs, strain on each thyroid lobe was induced by external compression using the ultrasound probe and internal compression using carotid artery pulsation after dobutamine infusion. The thyroid appeared homogeneously green and the subcutaneous fat superficial to the thyroid lobe appeared blue. Strain values and strain ratios did not differ among dogs or between the left and right lobes. Interobserver repeatability was excellent for both compression methods. Intraobserver repeatability of the strain ratio measured using the carotid artery pulsation method (intraclass coefficient correlation = 0.933) was higher than that measured using the external compression method (0.760). Mean strain values of thyroid lobes for the external compression method (142.93 ± 6.67) differed from the internal method (147.31 ± 8.24; P < 0.05). Strain ratios between the two methods did not differ. Strain elastography was feasible for estimating thyroid stiffness in dogs. Carotid artery pulsation induced by dobutamine infusion can be used for canine thyroid strain elastography with excellent repeatability.  相似文献   
5.
In the present study, the use of dogs with experimental autoimmune encephalomyelitis (EAE) as a disease model for necrotizing encephalitis (NE) was assessed. Twelve healthy dogs were included in this study. Canine forebrain tissues (8 g), including white and grey matter, were homogenized with 4 mL of phosphate-buffered saline for 5 min in an ice bath. The suspension was emulsified with the same volume of Freund''s complete adjuvant containing 1 mg/mL of killed Mycobacterium tuberculosis H37Ra. Under sedation, each dog was injected subcutaneously with canine brain homogenate at four sites: two in the inguinal and two in the axillary regions. A second injection (booster) was administered to all the dogs using the same procedure 7 days after the first injection. Clinical assessment, magnetic resonance imaging, cerebrospinal fluid analyses, necropsies, and histopathological and immunohistochemical examinations were performed for the dogs with EAE. Out of the 12 animals, seven (58%) developed clinically manifest EAE at various times after immunization. Characteristics of canine EAE models were very similar to canine NE, suggesting that canine EAE can be a disease model for NE in dogs.  相似文献   
6.
Butylated hydroxyanisole (BHA) is a synthetic phenolic compound consisting of a mixture of two isomeric organic compounds: 2-tert-butyl-4-hydroxyanisole and 3-tert-butyl-4-hydroxyanisole. We examined the effect of BHA against hydrogen peroxide (H2O2)-induced apoptosis in primary cultured mouse hepatocytes. Cell viability was significantly decreased by H2O2 in a dose-dependent manner. Additionally, H2O2 treatment increased Bax, decreased Bcl-2, and promoted PARP-1 cleavage in a dose-dependent manner. Pretreatment with BHA before exposure to H2O2 significantly attenuated the H2O2-induced decrease of cell viability. H2O2 exposure resulted in an increase of intracellular reactive oxygen species (ROS) generation that was significantly inhibited by pretreatment with BHA or N-acetyl-cysteine (NAC, an ROS scavenger). H2O2-induced decrease of cell viability was also attenuated by pretreatment with BHA and NAC. Furthermore, H2O2-induced increase of Bax, decrease of Bcl-2, and PARP-1 cleavage was also inhibited by BHA. Taken together, results of this investigation demonstrated that BHA protects primary cultured mouse hepatocytes against H2O2-induced apoptosis by inhibiting ROS generation.  相似文献   
7.
The spined soldier bug, Podisus maculiventris (Say), is a generalist predator that can control >75 insect pests in various agroecosystems. Despite valuable results from the previous studies, thermal development and survival of P. maculiventris over a wide range of temperatures had not been elucidated completely. This study was conducted to investigate the stage-specific development and survival of P. maculiventris at eight constant temperatures (13.2, 18.4, 21.7, 23.7, 27.2, 32.7, 35.2, and 40.6 °C) covering the entire thermal range for P. maculiventris development. Completion of egg development was observed at 13.2–32.7 °C, whereas nymphs successfully developed into adults at 18.4–32.7 °C. Survival model using log-normal equations showed bell-shape patterns for all stages, and temperatures resulting in highest survival of P. maculiventris were 19.9, 24.3, and 24.5 °C for egg, nymph, and egg to adult, respectively. Developmental rates at the eight temperatures were fitted with a nonlinear Briere model, which estimated optimal temperatures for development as 31.2, 30.6, and 30.6 °C for egg, nymph, and egg to adult, respectively. Operative thermal ranges (i.e., in-between the lower and upper developmental thresholds) were estimated to be 8.9–35.2, 12.8–35.2, and 12.7–35.2 °C for egg, nymph, and egg to adult, respectively. In a linear model, the lower thresholds were 10.9, 13.1, and 13.0 °C for egg, nymph, and egg to adult, respectively. Findings herein provide comprehensive data and explanations on optimal temperature and thermal requirement for P. maculiventris, which can be used to optimize environmental condition in mass rearing and predicting phenology of P. maculiventris in the field.  相似文献   
8.
The effect of acidic deposition on the soil under red pine forest in Chunchon, Korea was investigated. Precipitation, stream water, and soil solution chemistry were monitored at the watershed from 1997 to 1998. Acidity of the open-bulk precipitation was often neutralized by large amounts of ammonia (NH3) that might have originated from livestock farming and fertilization. Estimated elemental budget at the watershed showed a positive correlation between loss of base cations and proton (H+) production due to nitrogen transformation in soil (ΔH+ NT: ([NH4 +]in-[NH4 +]out)- ([NO3 ?]in-[NO3 ?]out)). When ΔH+ NT increased, concentrations of nitrate in soil solutions also increased. Consequently, pH values of soil solutions decreased, although ion exchange with base cations contributed to buffer reaction. Since acid buffering capacity of the red pine forest soil was small, it was concluded that the input of ammonium nitrogen enhanced nitrification in soil thus causing soil acidification represented by loss of base cations from the watershed.  相似文献   
9.
Kim JE  Kim HJ  Pandit S  Chang KW  Jeon JG 《Fitoterapia》2011,82(3):352-356
Rheum undulatum root has been used traditionally in Korea for the treatment of dental diseases. The purpose of this study was to separate a fraction from R. undulatum showing anti-acid production activity against Streptococcus mutans biofilms and identify the main components in that fraction. Methanol extract of R. undulatum root and its fractions were prepared. To select a fraction exhibiting anti-acid production activity, suspension glycolytic pH-drop assay was performed. Among the fractions tested, dichloromethane fraction exhibited the strongest activity in a dose-dependent manner. To examine the effect of the selected fraction on the anti-acid production of S. mutans biofilms, 74 h old S. mutans biofilms were used. The selected fraction reduced the initial rate of acid production of S. mutans biofilms at sub-minimum inhibitory concentration (MIC) levels. HPLC qualitative analysis of the selected fraction indicated that the presence of anthraquinone derivatives, such as aloe-emodin, emodin, chrysophanol and physcion, as main components.  相似文献   
10.
5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline derivative was synthesized, and its herbicidal activity was assessed under glasshouse and flooded paddy conditions. 5-(2,6-Difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline demonstrated good rice selectivity and potent herbicidal activity against annual weeds at 125 g of a.i. ha(-1) under greenhouse conditions. Soil application of this compound showed complete control of barnyard-grass to the fourth leaf stage at 250 g of a.i. ha(-1). Field trials indicated that this compound controlled annual weeds rapidly with a good tolerance on transplanted rice seedlings by post-emergence and soil application. This compound showed a low mammalian and environmental toxicity in various toxicological tests.  相似文献   
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