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111.
A rock pigeon (Columba livia) caught in Akihabara, Tokyo, showed neurological symptoms, such as head tilt and circling. Pathological examinations revealed abundant Sarcocystic cysts in the skeletal muscle and myocardium with mild myositis, and numerous schizonts and sarcocysts with severe multifocal granulomatous T-lymphocytic infiltration in the central nervous system. A Sarcocystis calchasi-specific gene was detected in the muscle and brain. This case indicates S. calchasi was distributed in Japan and caused severe encephalitis to rock pigeons.  相似文献   
112.
Thyroid hormones and oxidative stress play significant roles in the normal functioning of the female reproductive system. Nitric oxide (NO), a free radical synthesized by nitric oxide synthases (NOS), participates in the regulation of thyroid function and is also a good biomarker for assessment of the oxidative stress status. Therefore, the purpose of this study was to investigate effects of thyroid hormones on uterine antioxidative status in young adult rats. Thirty immature female Sprague-Dawley rats were randomly divided into three groups: control, hypothyroid (hypo-T) and hyperthyroid (hyper-T). The results showed the body weights decreased significantly in both the hypo-T and hyper-T groups and that uterine weights were decreased significantly in the hypo-T group. The serum concentrations of total triiodothyronine (T3) and thyroxine (T4), as well as estradiol (E2), were significantly decreased in the hypo-T group, but increased in the hyper-T group. The progesterone (P4) concentrations in the hypo- and hyperthyroid rats markedly decreased. Immunohistochemistry results provided evidence that thyroid hormone nuclear receptor α/β (TRα/β) and three NOS isoforms were located in different cell types of rat uteri. The NO content and total NOS and inducible NOS (iNOS) activities were markedly diminished in the hypo-T group but increased in the hyper-T group. Moreover, the activities of both glutathione peroxidase (GSH-Px) and catalase (CAT) exhibited significant decreases and increases in the hypo-T and hyper-T groups, respectively. The malondialdehyde (MDA) contents in both the hypo-T and hyper-T groups showed a significant increase. Total superoxide dismutase (T-SOD) activity in the hypo- and hyper-T rats markedly decreased. In conclusion, these results indicated that thyroid hormones have an important influence on the modulation of uterine antioxidative status.  相似文献   
113.
Typical skeletal muscles are composed of mixed muscle fiber types, which are classified as slow-twitch (type I) and fast-twitch (type II) fibers, whereas pectoralis major muscles (PMs) in broiler chickens are 100% composed of type IIb fast-twitch fibers. Since metabolic properties differ among muscle fiber types, the combination of muscle fiber types is involved in physiological functions and pathological conditions in skeletal muscles. In this study, using serial block-face scanning electron microscopy, we compared three-dimensional (3D) mitochondrial properties in type IIb fibers in broiler PMs and those in type I fibers of broiler gastrocnemius muscles (GMs) heterogeneously composed of slow- and fast-twitch muscle fibers. In type I fibers in the GMs, elongated mitochondria with numerous interconnections to form a substantial network among myofibrils were observed. Along with lipid droplets sandwiched by mitochondria, these features are an adaptation to effective oxidative respiration and constant oxidative damage in slow-twitch muscle fibers. In contrast, type IIb fibers in the PMs showed small and ellipsoid-shaped mitochondria with few interconnections and no lipid droplets, forming a sparse network. The mitochondrial spatial network comprises of active mitochondrial dynamics to reduce mitochondrial damage; therefore, type IIb fibers possess physiologically low capacity to maintain mitochondrial wellness due to static mitochondrial dynamics. Based on 3D mitochondrial properties, we discussed the contrasting physiological functions between type I and IIb fibers and proposed a high contractile power and low stress resistance as unique physiological properties of broiler PMs.  相似文献   
114.
An 8-month-old thoroughbred colt presented with sudden onset right forelimb lameness. A radiographic series of the right carpus was performed, and it revealed a slab fracture of the fourth carpal bone and fracture of the proximal part of the third metacarpal bone. Arthroscopically guided repair of the slab fracture of the fourth carpal bone with a 3.5 mm cortex screw and lag screw fixation of the fracture of the proximal part of the third metacarpal bone were performed. The horse started to race at 32 months old and started in 65 races over three years without any trouble associated with the right carpus.  相似文献   
115.
“春阳”大米蛋白对大鼠胆固醇代谢的调控作用   总被引:1,自引:0,他引:1  
选用蛋白水平(CP)为14%的"春阳"大米蛋白(RP)、大豆蛋白(SP)、酪蛋白(CAS)为食物蛋白源.喂养雄性20周龄Wistar大鼠.经2周饲养后,各试验组间大鼠的生长性能、蛋白质功效无显著差异.与CAS组相比,RP及SP显著降低了大鼠血浆总胆固醇、血浆非高密度胆固醇(LDL-C、VLDL-C)水平及肝脏总脂质、肝脏胆固醇、肝脏甘油三酯含量.RP及SP显著阻碍大鼠的肠道胆固醇吸收,其肝脏胆固醇酯化率均显著低于CAS组.数据显示,RP显著刺激大鼠中性粪同醇、粪胆固醇的排泄,但大鼠粪胆汁酸的排泄与CAS组无显著差异.对比CAS,RP能够有效降低成熟期大鼠动脉硬化指数.结果表明.富含醇溶蛋白的"春阳"大米蛋白能够有效调控成熟期大鼠的胆固醇代谢.显示与大豆蛋白-致的降低机体胆固醇水平的作用效果,其主要作用机制之一是有效阻碍肠道胆固醇的吸收,而非单纯地刺激粪胆汁酸的排泄.  相似文献   
116.
The purpose of this observational study was to determine the characteristic computed tomographic (CT) myelography findings of cervical vertebral stenotic myelopathy (CVSM) lesions in Thoroughbred horses. A total of 23 Thoroughbred horses (age range, 155–717 days on CT examination; mean, 410.9 days) were analyzed. All 23 Thoroughbred horses underwent unenhanced radiography, radiographic myelography, and CT myelography. Unenhanced radiographs were observed the presence of cervical vertebral malalignment and osseous lesions. Radiographic myelograms were observed for signs of cervical spinal cord compression; additionally, CT myelograms were used to detect cervical vertebral osseous lesions. Ventral compressions were frequently observed in the cranial cervical vertebrae (C2–C4), whereas dorsal compressions were frequently observed in the caudal cervical vertebrae (C5–C7). Furthermore, osseous lesions of the caudal articular process developed more frequently than those of the cranial articular process. CT myelography in Thoroughbred horses is a useful method for detecting CVSM changes.  相似文献   
117.
The effect of estrus induction by cabergoline on gonadotropin and steroid hormone responses was examined in anestrous bitches. Eleven beagles were used in the study; seven were included in the estrus induction group and four were included in the spontaneous estrus group. Cabergoline was orally administered to the estrus induction group at 5 µg/kg once daily for four weeks, or until hemorrhagic discharge was detected. The inter-estrus interval in the estrus induction group was significantly shorter than the previous estrus interval. Bitches that showed proestrus within four weeks of treatment showed increased luteinizing hormone (LH) pulse frequency and, subsequently, increased estradiol (E2) levels. Prolactin (PRL) levels declined promptly after treatment, except in one bitch that did not show proestrus during the cabergoline treatment period. There was a significant correlation between the time to proestrus induction and the reduction in PRL levels. A positive correlation was found between the LH levels two weeks after cabergoline administration and PRL reduction. This study demonstrates that an abrupt reduction in PRL is likely to be important for initiation of estrus in bitches. A reduction in PRL indirectly leads to an increase in LH pulse frequency, which regulates follicular development in bitches. However, if the period from the end of the previous estrus to the cabergoline treatment is short, it may take some time to show proestrus without increasing E2 levels, even if the LH level increases after cabergoline administration.  相似文献   
118.
The objective of this study was to investigate immunolocalization of steroidogenic enzymes 3βHSD, P450c17 and P450arom and their expression during the breeding season in wild male raccoon dogs. The testicular weight, size and seminiferous tubule diameters were measured, and histological and immunohistochemical observations of testes were performed. The messenger RNA expression (mRNA) of 3βHSD, P450c17 and P450arom was measured in the testes during the breeding season. 3βHSD was found in Leydig cells during the breeding and non‐breeding seasons with more intense staining in the breeding season. P450c17 was identified in Leydig cells and spermatids in the breeding season, whereas it was present only in Leydig cells in the non‐breeding season. The localization of P450arom changed seasonally: no immunostaining in the non‐breeding season; more extensive immunostaining in Leydig cells, Sertoli cells and elongating spermatids in the breeding season. In addition, 3βHSD, P450c17 and P450arom mRNA were also expressed in the testes during the breeding season. These results suggested that seasonal changes in testicular weight, size and seminiferous tubule diameter in the wild raccoon dog were correlated with spermatogenesis and immunoreactivity of steroidogenic enzymes and that steroidogenic enzymes may play an important role in the spermatogenesis and testicular recrudescence and regression process.  相似文献   
119.
A 4-year-2-month-old female Japanese domestic cat was diagnosed with lymphangiosarcoma through tissue biopsy of an amputated leg. Two months later, the cat was euthanized, and postmortem findings revealed edema, and bruising at the caudal region of the trunk, pulmonary hemorrhage, pulmonary nodules and mediastinal lymphadenopathy. Microscopically, neoplastic tissues were observed in the dermis and subcutis of the trunk, lung, mediastinal lymph nodes, diaphragm, omentum and mesentery. The tumor cells were spindle to polygonal-shaped with nuclear pleomorphism aligning along pre-existing collagen bundles and forming irregular vascular channels in which the erythrocytes were rarely observed. These cells were immunopositive for vimentin, von Willebrand factor and CD31. Based on the histopathological and immunohistochemical features, the neoplasia was diagnosed as lymphangiosarcoma with systemic metastases.  相似文献   
120.
Feline renal diseases are increasingly noted in veterinary practice. It is important to diagnose and identify the pathological basis of renal dysfunction accurately at an early stage, but there are only a few reports on this area in clinical veterinary medicine. We investigated the efficacy of measurement of urinary albumin (u-Alb) and urinary transferrin (u-Tf) for early diagnosis using 5-µl urine samples collected noninvasively by catheterization from normal (IRIS stage I) cats and cats with stage I chronic kidney disease (CKD). The u-Alb levels in normal and stage I CKD cats were 6.0 ± 4.5 and 11.2 ± 8.4 mg/dl, respectively, and the u-Tf levels were 0.09 ± 0.42 and 0.52 ± 0.79 mg/dl, respectively. Based on ROC curve analysis, the sensitivity and specificity of u-Alb and u-Tf were higher than those of the currently used biomarker, the plasma creatinine level. The sensitivity of u-Alb was higher than that of u-Tf, whereas the specificity of u-Tf was higher than that of u-Alb. The validity of the threshold albumin level (20 mg/dl) was confirmed by measurements using SDS-PAGE. Since leakage of u-Tf in urine precedes leakage of u-Alb, inclusion of u-Tf in biochemistry tests may be appropriate for IRIS staging as a diagnostic marker of early diagnosis of renal disorder in cats.  相似文献   
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