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B Petit

Publications and source records attributed to B Petit.

61 records · Page 4Linked to original sources
PubMedDate not supplied

Time to exhaustion at VO2max and lactate steady state velocity in sub elite long-distance runners.

The aim of the present study was to estimate the importance of lactate steady state velocity (WCL) of the running velocity at maximal oxygen uptake (Va max) and its time to exhaustion (Tlim), in the performance of a half marathon stated by the velocity over 21.1 km sustained by the runners during 1 h 12 min +/- 2 min 27 s. The population consisting of ten sub-elite male long distance runners (32 +/- 4 years old) was homogeneous with regard to their velocities on 21 km (V21 = 17.5 +/- 0.88 km.h-1, coefficient of variation, CV = 5%) and their aerobic maximal speed (Va max) (21.6 +/- 1.2 km.h-1, CV 6%). The fractional utilization of VO2max on 21 km was calculated from their own running economy (oxygen consumed per kilo of body mass and kilometer run (194 +/- 74 ml.kg-1.km-1). V21 represented 83 +/- 5% VO2max (VO2max = 68.1 +/- 4.1 ml.kg-1.min-1) and 81 +/- 3.3% Va max. The velocity corresponding to lactate steady state and called "lactate steady state velocity" (WCL) was measured according to a protocol proposed by CHASSAIN (1986). The subjects ran twenty minutes at a constant velocity representing 70-75% and 85-90% VO2max. Lactatemia was measured at the fifth (Lact 5) and the twentieth minute (Lact 20). Lactate slope was measured for two running velocities in order to determine the velocity (WCL) corresponding to lactate steady state, i.e. the lactate slope is equal to zero.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Cytokeratins expression in paragangliomas of the cauda equina.

BACKGROUND: Paragangliomas rarely involve the cauda equina region. In this location, these tumors can show misleading morphological features such as trabecular or papillary growth patterns and variable expression of cytokeratins. METHODS: We comparatively studied the immunohistochemical and ultrastructural patterns of 3 paragangliomas of the cauda equina (PCE) and of 8 paragangliomas from other sites. RESULTS: All the paragangliomas expressed neuroendocrine markers (neuron-specific enolase, chromogranin A, synaptophysin and neurofilament protein). In PCE, chief cells exhibited a strong positivity with a broad spectrum anti-cytokeratin antibody. The staining was diffuse in the cytoplasm or had a paranuclear dot-like disposition. In other sites, only one paraganglioma showed a focal expression of cytokeratins. At ultrastructural level, chief cells of PCE contained characteristic dense core granules and intermediate-sized filaments sometimes grouped in paranuclear whorls. CONCLUSION: The dual immunophenotype of PCE, paraganglionic and epithelial, must be recognized in order to distinguish these tumors from, for example, a metastasis of a neuroendocrine carcinoma. PCE are slow-growing tumors and have mostly a favorable prognosis after complete surgical excision.

Adolescent↗
PubMedDate not supplied

[Importance of elastic compression of the lower limbs in the prevention of venous thrombosis in digestive surgery].

A group of 25 patients having to undergo laparotomy were prescribed thrombo-embolic preventive stockings of graduated elasticity to be worm from 48 hours before the operation until 9 days afterwards. This group was compared to another group of 25 patients. The thromboses were detected using the fibrinogen test and the Doppler. This study demonstrates the efficiency of prophylactic anti-thrombotic stockings using graduated compression.

Adult↗