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91.
Since it has been suggested that lipid peroxidation following free radical overproduction may be one of the causes of physical exercise-induced myopathies and hemolysis in horses, we looked for the possible relationships between these phenomena and muscle fiber damage. We use a homogeneous group of Maremmana stallions which, after a 3-month training period, underwent a series of physical exercises of increasing intensity. We determined the contents of malondialdehyde (MDA), one of the main lipid peroxidation end-products, and glutathione the substrate of one of the most important free radical scavenger enzymes. We also measured creatine phosphokinase and serum lactate dehydrogenase isoenzyme activities whose modification may be indicative of muscle fiber damage. The results obtained indicated that the physical exercise we adopted was able to modify both MDA and glutathione contents in blood. However, its effect on some LDH isoenzyme activities suggested possible damage to tissues other than muscle.  相似文献   
92.
There is a controversy among prosthodontists concerning the most favourable superstructure design of a prosthesis supported by implants. Some investigators used the fully extended denture, others used a non extended. This study evaluated the load distribution pattern occurring in implants with the two designs. A real clinical situation which includes 4 osseointegrated implants that are connected to each other with a superstructure bar and support an acrylic dentures was transferred into a 3-D geometric model. With the 3-D FEM it was possible to compare between the two types of acrylic dentures.  相似文献   
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The accessory soleus muscle is a rare anatomic variant that may present as a mass in the posterior-medial aspect of the ankle in young adults. The presence of such a mass may result in pain and difficulty with running. We present a case of accessory soleus muscle in a 21-year-old soldier and review the literature. We present the first magnetic resonance imaging studies in the American literature, to our knowledge, of this unusual anomaly.  相似文献   
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T cells are normally activated when the peptide for which they are specific is presented to them in the context of the appropriate major histocompatibility complex (MHC) (class I and Class II for CD8+ and CD4+ T cells, respectively). An increasing body of evidence indicates that structural homologues of the immunogenic peptide can partially activate or antagonize CD4+ T cells. CD8+ T cells may also be partially antagonized by such peptides, and self-derived peptides of this type may play a role in CD8+ T cell selection in the thymus. Activated CD8+ T cells lyse their targets by perforin-dependent granule exocytosis and by inducing apoptosis mediated by CD95 (also known as Fas or APO1) with its ligand (CD95L). Here we show that a clone of Kd-restricted CD8+ T cells specific for influenza haemagglutinin, which can also be activated in a crossreactive manner by a peptide derived from a myeloma tumour immunoglobulin heavy-chain variable region (IgVH) to kill by both routes, kills only by the CD95-CD95L pathway when stimulated by the corresponding germline IgVH peptide. As this germline IgVH peptide differs from the tumour peptide only at a single position buried in the MHC-binding groove, this indicates that CD95-CD95L-mediated killing can be triggered independently of the perforin-mediated pathway, and can be selectively affected by changes in MHC conformation.  相似文献   
98.
Tumor markers are used to diagnose certain cancers and can be useful in monitoring the response to treatment. We describe a renal tumor with the features of a teratoid nephroblastoma associated with a raised serum level of alpha-fetoprotein (AFP). The serum AFP remained high during chemotherapy but returned to normal after nephrectomy. AFP was demonstrated by immunohistochemistry in cysts lined by enteric-type epithelium within the tumor. Cytogenetic examination of the tumor showed a clone of cells with trisomy 8. Raised serum AFP has not previously been described in teratoid Wilms' tumor.  相似文献   
99.
BACKGROUND: Escherichia vulneris is an enterobacteriaceae seldom isolated in microbiology laboratories. We report two cases of infection with positive cultures for this microorganism. METHODS: Microbiological cultures of wound secretion and peritoneal fluid on usual media. Identification by PASCO and API 20E systems. Antimicrobial sensitivity was performed by a commercial microdilution system. RESULTS: The first case is a postsurgical hand infection from which was isolated Escherichia vulneris with Enterococcus faecium, it shows the typical presentation of infection by this bacteria. The second case consists of a peritonitis after aggressive abdominal surgery. In the peritoneal fluid culture, Escherichia vulneris and Cedecea neteri were recovered. CONCLUSIONS: The isolation of Escherichia vulneris has not been reported previously in Spain. We contribute towards its better knowledge with two clinical reports: a typical infection and an exceptional isolation from peritoneal fluid.  相似文献   
100.
N-phenyl-carbamate of D-mannonohydroxymolactone (I) was synthesized from mannose and was shown to be the best competitive inhibitor of beta-mannosidase so far reported (Ki = 25 nM).  相似文献   
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