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991.
We examined male shoal bass Micropterus cataractae from the Flint River, Georgia, to determine the prevalence of intersex. During March and April 2010, we sampled 61 shoal bass from six sites along the Flint River. Testes were examined histologically and classified as intersex if the presence of oocytes was noted. Using a severity index, we compared samples collected on different dates and from different locations according to age and testis weight. No significant variations were noted among any of the groupings. Further investigation is needed to determine whether the intersex condition in shoal bass is severe enough to warrant concern and whether it is a natural phenomenon.  相似文献   
992.
Understanding the inherent radiosensitivity and repair capacity of canine transitional cell carcinoma (TCC) can aid in optimizing radiation protocols to treat this disease. The objective of this study was to evaluate the parameters surviving fraction at 2 Gy (SF(2) ), α/β ratio and capacity for sublethal damage repair (SLDR) in response to radiation. Dose-response and split-dose studies were performed using the clonogenic assay. The mean SF(2) for three established TCC cell lines was high at 0.61. All the three cell lines exhibited a low to moderate α/β ratio, with the mean being 3.27. Two cell lines exhibited statistically increased survival at 4 and 24 h in the dose-response assay. Overall, our results indicate that the cell lines are moderately radioresistant, have a high repair capacity and behave similarly to a late-responding normal tissue. These findings indicate that the radiation protocols utilizing higher doses with less fractionation may be more effective for treating TCC.  相似文献   
993.
994.
The rate of osteogenesis was studied in 8 non-pregnant, non-lactating Friesian dairy sheep, 3–6 years old, by means of a treatment with 3 different bone seeking agents. Four sheep were fed a low calcium ration (LCa : 1.8 g Ca/d) and four other sheep a high calcium ration (HCa : 12.7 g Ca/d). The bone markers, oxytetracycline-HCl, alizarine-complexon and demeclocycline-HCl, were administred at intervals of 6 weeks, and the sheep were killed 1 week after administration of the last marker. In undecalcified cross sections from the middle of ribs 2, 10 and 12, and from the proximal and distal parts of rib 10, the numbers of labelled osteons and the number of osteons with 1, 2 or 3 markers were counted under fluorescent microscopy.In the ribs of sheep from the LCa group, the number of labelled osteons and the quantity of labels per osteon tended to be higher than those of sheep from the HCa group. When osteogenic activity was compared in the different sites of ribs analysed, lowest osteogenic activity was observed in the proximal part of the 10th rib.The use of fluorescing markers offers the possibility of studying osteogenic activity over a certain period of time in adult sheep.  相似文献   
995.
996.
Disseminated Mycobacterium paratuberculosis infection in a cow   总被引:7,自引:0,他引:7  
A cow with chronic diarrhea and weight loss caused by localization of Mycobacterium paratuberculosis in the intestinal tract (Johne's disease) had gross and microscopic changes indicative of a disseminated infection. A direct association between the remote lesions and the intestinal infection was shown by isolation of M paratuberculosis from renal tissue, detection of intracellular M paratuberculosis antigen(s), using an indirect immunoperoxidase method, and by the characteristic granulomatous nature of the lesions. This case illustrates the potential for extra-intestinal lesions in M paratuberculosis infection of cattle and should cause veterinarians to consider mycobacterial disease when confronted with multinodular lesions of the bovine kidney. The immunoperoxidase method was useful in determining the cause of the inflammatory lesion in which intact organisms were not evident.  相似文献   
997.
998.
The examination of 70 cattle with haematogenous osteomyelitis resulted in the classification of the bone lesions into two main groups: the physeal type, in which an infection, usually of metaphyseal bone, originated at or near the growth plate, usually in the distal metacarpus, metatarsus, radius or tibia, and the epiphyseal type, in which an infection originated near the junction of the subchondral bone and the immature epiphyseal joint cartilage, most often in the distal femoral condyle epiphysis, the patella and the distal radius. Combinations of physeal and epiphyseal defects and even diaphyseal involvement were occasionally seen. Epiphyseal osteomyelitis was mostly caused by salmonella infection, physeal by Corynebacterium pyogenes, salmonella and other bacteria. The salmonella affected animals were with one exception less than 12 weeks old and the majority had had some previous illness or came from a problem herd. The C pyogenes affected calves were in almost all cases more than six months old. The prognosis of the metaphyseal infection was in general satisfactory, and surgical intervention (osteotomy or sequestrectomy) was often required. The prognosis of the epiphyseal type was grave but two of the three animals in which physeal and epiphyseal defects were accompanied by diaphyseal lesions recovered.  相似文献   
999.
The mydriatic effect of 10% phenylephrine was evaluated in 9 horses. Base-line pupillary size in mesopic conditions and during light stimulation was ascertained before application of pharmacologic agents. In study 1, 10% phenylephrine was applied to each eye (n = 5 horses). After 15 minutes, the pupillary size was determined in both lighting conditions. Phenylephrine was again applied to each eye, and after an additional 15 minutes, the pupillary size was determined. In study 2, 1% tropicamide was applied to each eye (n = 4 horses), and after 30 minutes, the pupillary size was determined in both lighting conditions. Tropicamide and phenylephrine were applied to each eye immediately after determination of pupillary size, and after an additional 30 minutes, the pupillary size was determined. There was no significant change (P greater than 0.9) in pupillary size when phenylephrine was used alone or when phenylephrine was used in an eye that had been dilated with tropicamide.  相似文献   
1000.
Infection with Borrelia burgdorferi caused arthritis, myocarditis, glomerulonephritis, and pneumonitis in a cow. Spirochetes were detected by use of immunofluorescent staining in liver and lung specimens and were isolated from the liver. The carpal, stifle, and tarsal joints had marked synovial proliferation, and synovial fluid obtained from these joints had high antibody titers against B burgdorferi. The cow was from an area of Wisconsin that is not endemic for borreliosis.  相似文献   
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