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121.
This study was conducted to investigate the effects of dietary synthetic β‐carotene on growth performance, haematological and immunological parameters, energy reserves and antioxidant status of juvenile fish Piaractus mesopotamicus. Two hundred and ten fish (12.24 ± 2.98 g) were fed with a control extruded feed (CEF) and the same diet supplemented with β‐carotene (BEF) for 90 days. A higher weight gain and specific growth rate were found in fish fed BEF in comparison with those fed CEF. In addition, BEF‐fed fish showed lower liver somatic index and a higher percentage of eosinophils. No statistical differences were found in energy reserves, except for plasma triglycerides which decreased in fish fed with BEF. Regarding oxidative stress markers, decreased activities of antioxidant enzymes were found in intestine and gills of BEF‐fed fish (SOD and GST, respectively). In the liver, both LPO levels and CAT activity decreased in fish fed with BEF. Additionally, lower brain LPO levels without changes in the antioxidant enzymes were observed in BEF‐fed fish. The inclusion of dietary synthetic β‐carotene improved growth and antioxidant status, and had a plasma triglyceride‐lowering effect in juvenile P. mesopotamicus.  相似文献   
122.

Purpose  

The rooted zone of a soil, more precisely the rhizosphere, is a very dynamic system. Some of the key processes are water uptake and root respiration. We have developed a novel method for measuring the real-time distribution of water and oxygen concentration in the rhizosphere as a biogeochemical interface in soil. This enables understanding where and when roots are active in respect to root respiration and water uptake and how the soil responds to it.  相似文献   
123.
The karyotype, the histological structure of the testis and the synaptonemal complex (SC) of the mammalian species Tayassu tajacu , Tayassu pecari and of an interspecific male hybrid captured in nature were analysed. The specimens of T. tajacu (2n=30) and T. pecari (2n=26) exhibited seminiferous tubules with germ cells in all spermatogenesis stages. In the SC studies both species had a regular structure, easily identified in the autosomes and in the sex chromosomes. The hybrid (2n=28) had seminiferous tubules with almost all germinal cells in the spermatogonium stage and only a few cells in the primary spermatocyte stage. Gross abnormalities in SC were observed. A few lateral elements showed regular or partially regular synapsis, other lateral elements were synapsed as multivalents, and most axial elements remained unsynapsed. The results suggest that the karyotypes of the parental species have sufficient differentiation to avoid chromosome synapsis. Alternatively, the hypothesis of the existence of genetic incompatibilities between the parental species is discussed.  相似文献   
124.
The medical records of 220 dogs with inflammatory/infectious diseases of the central nervous system (CNS) were retrospectively examined. The aims of the study were to determine if clinical and clinicopathologic data (not including biopsy or necropsy examination) could distinguish inflammatory CNS diseases from diseases of other types, and to search for criteria allowing differentiation of specific inflammatory diseases. The signalment, historical findings, extraneural and neurological signs, and the lesion site contributed marginally to a specific diagnosis. Multifocal signs were only noticed in one third of the dogs with inflammatory/infectious diseases. Particular neurological abnormalities were more frequent in certain diseases than in others (eg, myoclonus was frequent in dogs with distemper, but it was also found in those with other meningoencephalomyelitides). Hematologic findings contributed to the diagnosis in certain conditions (eg, canine distemper encephalitis, protozoal encephalomyelitis, steroid-responsive meningitis-arteritis). Cerebrospinal fluid examinations, including immunoglobulin G index and cytology were useful to separate meningoencephalomyelitides from the other CNS diseases and to distinguish certain conditions from others. In most cases a specific diagnosis depended on a combination of clinical signs and ancillary diagnostic aids. Still, a specific diagnosis remained very difficult, if not impossible, in at least one third of the dogs.  相似文献   
125.
The ochratoxin A (OTA) content of urine samples from 88 healthy humans living at five settlements in three counties of Hungary was determined by immunoaffinity column cleanup and high-performance liquid chromatography (HPLC). OTA was detected in 61% of the samples in an average concentration of 0.013 ng/ml (range: 0.006-0.065 ng/ml). OTA concentrations measured in urine samples from men and women were not significantly different. The OTA concentration of samples from Heves county was significantly (t-test; p < 0.003) higher than that of samples from Hajdú-Bihar and Somogy counties. The regional differences in OTA concentration of urine samples indicate regional differences in the OTA exposure of the human population. Further studies are necessary to determine the cause of the regional differences in the OTA intake. The studies allow us to conclude that the OTA intake of the majority of the Hungarian population is low (< 1 ng/kg of body weight per day) but a certain part of the rural population may take up higher levels of OTA.  相似文献   
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127.
A large splenic mass was found during exploratory celiotomy in a 12-year-old Labrador retriever. Histologic examination of the mass revealed a mesenchymal chondrosarcoma. The dog was euthanatized 7 wk postoperatively, due to suspected tumor recurrence. Extraskeletal mesenchymal chondrosarcomas are rare in dogs and are associated with a guarded prognosis.  相似文献   
128.
A 12-year-old, intact male, mixed-breed dog was evaluated after surgical removal of a mast cell tumor from the shoulder. Results of laboratory tests were within the reference ranges, but examination of urinary sediment identified epithelial cells of the upper urinary tract and microscopic hematuria. Abdominal ultrasound examination performed after a 12-hour fast identified a simple cyst in the left kidney. The cyst was approximately 26 mm in diameter, was anechoic, and had a thin, slightly hyperechoic wall with distal acoustic enhancement accompanied by dilatation of the caudal papillary duct and renal pelvis (Fig 1). Excretory urography with iopamidola contrast (800 mg/kg IV) confirmed the presence of dilatation of the left renal pelvis and collecting system (Fig 2).  相似文献   
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