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The aim of this study was to examine hormonal and metabolic changes in a group of 18 professional male cyclists ((.)VO(2)max 69.9 [95 % CI 64.9 to 74.9] mL x kg(-1) x min(-1) ) during two successive periods of adapted intensive training. The second training period included 4 days of cycling competition. Intensity was increased while volume was decreased in the second training. Anthropometric data were collected before and at the end of the two training periods. Venous blood samples were taken in a basal state before the two training sessions and after each training session. Serum concentrations of cortisol (C), testosterone (T), dehydroepiandrosterone sulfate (DHEAs), and catecholamines were determined as well as branched-chain amino acids (valine, leucine, isoleucine) (BCAA) and free fatty acids (FFAs). At the end of the two training periods, the subjects lost fat mass whereas mean body mass was unchanged. The T/C ratio was reduced transiently after the first training session (45.90 %), while DHEAs/C remained unchanged. T/C and DHEAs/C were significantly increased after the second training session compared to the first (48.40 and 97.18 %, respectively). Catecholamines and FFAs were unchanged. The significant increase in BCAA levels after the second training session was of note as it might constitute a "store shape" of amino acids in anticipation of future intense training loads. Based on the responses of testosterone, DHEAs, and cortisol, and on the training-induced increase in BCAA, there appeared to be hormonal and metabolic adaptation despite the inherent psychological stress of competition.  相似文献   
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Analysis of the HIV-1 V3 quasispecies present in an individual at the time of seroconversion was carried out. The polymerase chain reaction (PCR) was used to amplify proviral HIV-1 DNA extracted from peripheral blood mononuclear cells from a patient who was viraemic (p24 = 15 pg/ml) and had an equivocal HIV-1 antibody status. The PCR products were cloned and the DNA sequence determined for 15 clones. These data showed that the V3 region contained only limited sequence heterogeneity with a major variant accounting for 66% of the protein quasispecies present. The protein sequence of the principal neutralising domain on all species contained the relatively rare GPGKTL motif rather than GPGRAF. The relevance of these data for early stages of HIV infection are discussed.  相似文献   
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We are elaborating on the kinetics and mechanisms of septic rabbit liver to de novo biosynthesize acute-phase response (APR) proteins under in vitro conditions of deepening ischemia in reference to their in vivo prevalence in serum and cerebrospinal fluids (CSF) collected at predetermined times. The significance of the data is interpreted as relevant to grafting cadaveric liver into end-stage liver diseased patients and APR-induced ischemic heart diseases (IHD). Hepatic APR was induced by CCl(4)-intubation, and the administration of cholera toxin (CT) or scorpion venom (SV), or both, to rabbits. Hepatic functional efficiency, in terms of biosynthesis of APR proteins in closed circuit perfusion of the isolated intoxicated liver with oxygenated saline or L-15 media paralleled the two-dimensional immunoelectrophoresis (2D-IEP) spectrum of APR serum proteins at time of liver isolation. We are suggesting: (a) in vitro biosynthesis of plasma proteins by isolated perfused liver is the result of in vivo decoded and retained APR inflammatory signals; and (b) decoded inflammatory signals are expressed not withstanding the perfusate's organic composition. Furthermore, 90 min of ischemic perfusion in saline or L-15 medium precipitated mitochondrial aberrations which resulted in further deterioration of de novo biosynthesis of APR plasma proteins. Regardless of the nature of the inflammatory stimuli, mitochondrial aberrations rendered the perfused organ a biologically inert tissue mass that was incapable of resuming biological function upon perfusion with oxygenated L-15 medium. This is most likely due to ischemia-induced irreversible hepatic necrosis. Thus, in vitro aberrations of mitochondrial function(s) critically limit the capability of the isolated liver to resume its organic function to sustain biosynthesis of de novo plasma proteins. Extrapolation of these results to the surgical management of end-stage liver diseases points to the importance of the status and the handling protocol(s) of the cadaver donor liver prior to successful grafting. We conclude that although histology of a cadaver liver may reveal well-preserved hepatic cellular organelles with at least minimal intra- and intercellular communication required for viable hepatic function, we deem it essential to further define acceptable minimal capabilities to de novo biosynthesize plasma proteins by a cadaver liver as a measure of its functional viability and suitability for transplantation. Ultimately, this measure may improve the success of liver transplants with minimal surgical and drug interventions.  相似文献   
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BACKGROUND: We report a case of non-Hodgkin's malignant lymphoma of the cervicofacial region revealed by unilateral exophthalmos and blindness, an unusual mode of expression. CASE REPORT: A 40-year-old man with a 4-month history of diabetes mellitus had suffered from exophthalmos and blindness of the right eye for 20 years. Physical examination showed a homolateral hemifacial tumefaction and ophthalmoplegia. The right ocular fundus showed papillar edema and non-proliferative diabetic retinopathy. The left eye was normal. The otolaryngology explorations revealed a voluminous tumor in the anterior nasal cavity and in the cavum. Two biopsies were performed. Histology reported non-Hodgkin's T-cell lymphoma. Orbitocerebral and cervicofacial computed tomography visualized the aggressive ethmoidomaxillary extension with intraorbital and intracranial involvement. Chemotherapy (CHOP) combined with radiotherapy led to tumor regression and involution of the exophthalmos. Diagnostic difficulties, management and prognosis are discussed.  相似文献   
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PURPOSE: - To assess the outcome and prognostic factors of patients with primitive intracranial ependymomas treated at the department of radiotherapy of Salah-Aza?z Institute. METHODS AND MATERIAL: - Between 1972 and 1997, 31 patients aged one to 53 years received postoperative radiotherapy. There were 16 males and 15 females. Location of tumor was infratentorial in 24 cases and supratentoriel in seven cases. Surgical treatment consisted of complete resection in 14, incomplete resection in 13 and unknown type in four patients. All patients were treated with radiotherapy to the craniospinal axis in 26 cases, whole brain in five cases. RESULTS: - Five years survival rate was 63%. For infratentorial tumors, two patients failed locally, two patients failed locally and at distance and four patients failed only at distance, while one patient with supratentorial tumor relapsed locally. Age, performances status, tumor site, gender and extent of surgery had no impact on survival. The treatment field extent was the only variable predictive of outcome. Patients treated with craniospinal irradiation had a survival rate of 86% compared with 37,5% for patients treated with whole brain irradiation. CONCLUSION:- Infratentorial ependymomas seem to have a worse prognosis than supratentorial ones. Irradiation field extent should be correlated to prognostic factors.  相似文献   
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Primary intramedullary ependymomas: retrospective study of 16 cases]   总被引:2,自引:0,他引:2  
PURPOSE: To review the radiotherapy department experience in treating primary spinal cord ependymomas (PSCE), analyse prognostic factors and provide treatment recommendations regarding literature review. MATERIALS AND METHODS: Sixteen patients with PSCE received postoperative radiotherapy between 1972 and 1997. There were 10 male and 6 female patients with a mean age of 34 years (range 2-63). Surgery was gross total resection in 2 cases, subtotal resection in 9, biopsy in 4 and of unknown type in one patient. All patients were treated with radiotherapy to the craniospinal axis (4 cases), spinal cord (1 case) and to the site of primary tumour in 11 cases. RESULTS: Five year-survival rate was 73%. Two patients had recurrent tumours within the primary site. Gender, extent of surgery and treatment field extent were not prognostic factors. Histologic type was the only variable predictive of outcome. Patients with myxopapillary type had a 5-year survival rate of 100% compared with 47% for those with other histology types. CONCLUSION: We conclude that aggressive surgery is not necessary in the management of PSCE, localised field radiotherapy is associated with favourable outcome, and tumour grade is an important prognostic factor.  相似文献   
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