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1.
Despite evidence from previous unit recording, microstimulation, lesioning and anatomical studies, the functions of the midbrain periaqueductal gray (PAG) remain unclear. We attempted to clarify the function of the PAG by recording activity of PAG units along with laryngeal and respiratory electromyograms (EMG) during vocalization in awake monkeys. PAG units were classified with respect to vocalization on the basis of their discharge patterns as 'early burst', 'late burst', 'tonic-increase' and 'tonic-off', with the vast majority being of the early- and late-burst type. Early-burst cells were correlated most frequently with inspiratory muscles of the respiratory system and laryngeal abductor muscles. Late-burst cells were most clearly correlated with laryngeal adductor and expiratory respiratory muscles. Data from spike-triggered averaging and parametric correlations indicate that most cells are related to single muscles, but a significant number were related to functionally related groups of two or more muscles. The results suggest that the PAG determines qualitative aspects of vocalization by the multisynaptic action its cells have on laryngeal and respiratory motoneurons. 相似文献
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J W Cox L G Dring L C Ginsberg P G Larson D A Constable R G Ulrich 《Drug metabolism and disposition》1990,18(5):726-731
Trospectomycin sulfate is an experimental, aminocyclitol antibiotic. It has been shown in preclinical, chronic safety studies in the dog and rat to elicit a reversible, lysosomal phospholipidosis in liver. The present experiments were conducted to characterize the tissue distribution and disposition of 3H]trospectomycin sulfate in the male rat, perfused rat, perfused rat liver, and cultured rat hepatocytes. Following a 5 mg/kg iv dose to four rats, approximately 70% of the dose was recovered within 24 hr primarily in urine as unchanged drug, and the remainder was eliminated with a terminal phase half-life in blood and tissues of 3 days. Fecal excretion was relatively minor (16% of the dose recovered in feces in 7 days) until later timepoints, when it was the principal pathway of terminal phase elimination. The liver sequestered approximately 10% of the dose and had the highest tissue levels of drug at all times measured. Liver perfusion experiments indicated that trospectomycin accumulated in a hepatic depot compartment as parent drug by a first-order process which was nonsaturable up to a 1 mM concentration of drug. Biliary excretion of unchanged trospectomycin by the perfused liver was slow (approximately 3% of the dose in 2 hr) and occurred by both paracellular and transcellular mechanisms. The hepatic depot compartment appeared to be responsible for transcellular biliary excretion, and thus for the sustained fecal excretion observed in vivo. Subcellular distribution experiments indicated that at least 50% of the drug in the hepatic depot was sequestered in organelles having a broad density range. The existence of a trospectomycin depot compartment was also demonstrated in cultured hepatocytes.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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M J Pliskin M L Dresner L H Hassell J R Gusz P W Balkin K S Lerud A W Larson 《The Journal of urology》1990,144(6):1459-1461
We report a case of a 5.8 cm. right renal artery aneurysm diagnosed intact 8 weeks post partum. Rupture of a renal arterial aneurysm during pregnancy is a rare but well described catastrophic event. There are no previous reports of an intact renal artery aneurysm diagnosed either ante partum or post partum. To our knowledge, this also represents the largest reported renal artery aneurysm. The aneurysm was repaired successfully with kidney salvage and closure of the fistulous connection to the renal vein. 相似文献
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V Brattstr?m J McWilliam G Semb O Larson 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》1992,26(1):55-63
Lateral skull radiographs of 85 patients with unilateral clefts of the lip, alveolus and palate treated according to four different regimes were compared longitudinally, at three different ages, regarding mandibular and vertical facial development. It was found that there were no lasting differences in mandibular morphology resulting from regimes including primary or early secondary bone grafting. The non grafted group, however, showed increased mandibular length and anterior height. The jaw angle was increased and there was a more favourable sagittal jaw relationship. Regimes that included primary bone grafting were associated with reduced upper anterior facial height, which resulted in less harmonious facial proportions compared with treatment regimes including early secondary bone grafting done during the mixed dentition, or no bone grafting at all. Vertical development was greatest where bone grafting was excluded. 相似文献
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L H Daltroy C B Phillips H M Eaton M G Larson A J Partridge M Logigian M H Liang 《American journal of public health》1995,85(4):558-560
The Physical Capacity Evaluation, a performance measure of functional capabilities comprised of 13 tasks simulating those used in activities of daily living, was tested on 289 community-dwelling elderly people and compared against a widely used self-report measure of function, the Health Assessment Questionnaire. Factor analysis identified one dominant component in each instrument. Internal consistency reliability (Cronbach's alpha) was .90 for both instruments. Global disability (Health Assessment Questionnaire) and function (Physical Capacity Evaluation) scores were correlated -.74. One-week retest reliabilities on 58 subjects were .94 for the Physical Capacity Evaluation and .95 for the Health Assessment Questionnaire. The Physical Capacity Evaluation is a valid and reliable measure of physical performance for use with elderly people. 相似文献
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