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931.
GM Kavanagh JP Leeming GM Marshman NJ Reynolds JL Burton 《Canadian Metallurgical Quarterly》1993,129(6):696-699
Twenty-two male and 20 female adults with Down's syndrome were examined. Ten of the men and two of the women had a follicular rash consistent with Malassezia folliculitis. Oral itraconazole treatment produced a significant improvement in the rash, accompanied by a decrease in the skin Malassezia count. Clinical relapse occurred when therapy was discontinued, and was accompanied by return of the Malassezia yeasts. 相似文献
932.
The ionic components of the action potential (AP) in rabbit right papillary muscle (RRPM) were determined by simple methods such as changes in external concentrations of sodium and calcium ions and addition of MnCl2 ot the perfusion fluid. Two components (fast and slow) were clearly visible in the upstroke of AP in normal Tyrode solution. MnCl2 (5 mmol/l) eliminated the slow component which forms the overshoot (OS) leaving the fast one unaffected, indicating that the former was related to a slow inward current. Mn also drastically reduced AP duration without changing the slope of phase 3 of repolarization. Reduction of Na concentration to 90 mmol/l did not affect the peak voltage of the OS but shortened AP. This low-Na solution reduced both (Vmax)f and the amplitude of the fast component. Ca-free solution reduced OS and increased AP duration. In high-Ca Tyrode (7.2 mmol/l) OS was increased and AP shortened. The effects of MN were reversed in this solution. The results suggest that the upstroke of the RRPM action potential is determined by two different ionic currents: a fast Na current responsible for the fast component and a slow inward current carried mainly by Ca, this latter being responsible for the slow component in the upstroke and for the plateau phase. The existence of propagated, Ca-dependent slow responses was demonstrated. Emphasis is placed on the fact that the major determination of the repolarization process in this type of AP is probably the inactivation of the slow inward Ca current. 相似文献
933.
J Saiz Martínez-Acitores I Saiz Martínez-Acitores A Sánchez-García JL González de Zárate A Velasco-Martín 《Canadian Metallurgical Quarterly》1980,35(8):691-697
Clozapine, a neuroleptic drug isostere of the phenothiazines, at a dose of 10(-3) M decreased the oxygen consumption of rat brain slices and homogenates. However, this effect was not potentiated when brain slices were incubated with 100 mM potassium or in a calcium-free medium, the uncoupling of brain mitochondrial oxidative phosphorylation by 10(-3) M clozapine can also be rulled out. 相似文献
934.
H Pavlovitch TL Clemens D Laouari JL O''Riordan S Balsan 《Canadian Metallurgical Quarterly》1980,86(3):419-424
A 20-year-old woman lost all useful vision over a 2 1/2-month period as a result of a necrotizing and occlusive vasculitis of the retina. Treatment with prednisone, immunosuppressants, and aspirin was unsuccessful. No systemic manifestations of the disease were found and no cause was discovered. Kodachromes and fluorescein angiograms showed the progression in one eye from normal to near total retinal necrosis. The process began with a mild venous dilation and peripheral arteritis that progressed into an obliterative vasculitis with abrupt vessel dilation, hemorrhages, and retinal swelling. This was followed by necrosis and sloughing of the retina into the vitreous. Vitreous contraction and necrotic retina produced unrepairable retinal detachments. 相似文献
935.
936.
MJ Kantor Herring KH Leef RG Locke JL Stefano L Bartoshesky DA Paul 《Canadian Metallurgical Quarterly》2003,20(6):333-339
Transient hypothyroxinemia is common in premature infants and has been associated with intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL), poor neurodevelopmental outcomes, and mortality. Recent trials have failed to show that supplemental thyroid hormone improves overall neurodevelopmental outcome. The objective of this article is too determine perinatal risk factors for transient hypothyroxinemia (TH). We studied a cohort of infants born between July 1993 and July 2000 who were less than 1500 g and who received a newborn screening for thyroid function ( n = 932). Total serum thyroxine (T(4)) was collected routinely on the fifth day of life. T (4) was correlated with gestational age (R = 0.59, p < 0.01). After controlling for potential confounding variables, gestational age, dopamine, and mechanical ventilation were found to be independently associated with low T (4) (overall model: r(2) = 0.41, p < 0.01). Number needed to treat (NNT) analysis showed treating all infants less than 27 weeks would lead to treating 6.3 infants for every one with a subsequent T(4) < 5 microg/dL. By combining gestational age and need for dopamine support, NNT = 2.4 for every one infant with subsequent T(4) < 5 microg/dL. Low gestational age, mechanical ventilation, and need for dopamine were associated with low T(4) levels and may be helpful in optimizing treatment strategies for TH. 相似文献
937.
A shortage of occupational medicine physicians exists for which a number of solutions have been proposed. The lack of board-certified specialists to address the increasingly complex issues encountered in this area of medicine has contributed to a credibility and identity crisis within the occupational medicine community. This article will review the significance of board certification and its importance for enhancing and preserving the specialty of occupational medicine. 相似文献
938.
939.
GN Piquette JL Tilly LE Prichard C Simón ML Polan 《Canadian Metallurgical Quarterly》1994,1(4):297-301
OBJECTIVE: The purpose of this study was to determine whether cells acquired from individual human preovulatory follicles undergo apoptosis (physiologic cell death) and, if so, to correlate the degree of apoptosis with characteristics of the follicles or the oocytes derived from the follicles. METHODS: We devised a sensitive nonradioactive method for detecting apoptotic DNA fragmentation in small numbers of cells derived from rat atretic follicles and follicular aspirates of patients undergoing assisted reproductive technologies. RESULTS: Using this method, apoptotic DNA was detected in rat atretic follicles, with optimal detection at 10-100 ng. Furthermore, apoptotic DNA was detected in some, but not all individual human follicular aspirates from several patients, and was found in follicles that produced oocytes that fertilized and developed into embryos. CONCLUSION: Apoptosis occurs in cells from human ovarian preovulatory follicles and may be a normal physiologic process of the follicle during luteinization. 相似文献
940.