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101.
Hypervitaminosis D produces extensive vascular alterations which are similar to Monckeberg's calcinosis. The present study was undertaken to examine early changes in vascular ultrastructure of rats receiving tap water supplemented with either calcium chloride or a relatively low dosage of irradiated ergocalciferol ad libitum for 21 days. Untreated rats received normal tap water ad libitum. A significant increase in serum calcium levels was obtained in hypervitaminosis D treated rats. Calcium deposits were seen near the internal elastic lamina, within new elastic elements and around degenerating smooth muscle cell fragments in the extracellular organic matrix of hypervitaminosis D treated rats. Calcium deposits were not detected in vascular sections from untreated rats or those receiving calcium chloride. A complex pathogenesis of vascular lesions produced by hypervitaminosis is suggested. One possible pathogenic mechanism for calcification of elastic matrix may be via altered microfibrils. Our data support this hypothesis and indicate that much lower levels of vitamin D administration, compared to other reports, produce considerable vascular calcinosis in this experimental preparation. Several hypotheses regarding possible mechanisms of pathologic calcification are discussed. 相似文献
102.
103.
J J Defauw N M van Hemel F E Vermeulen J H Kingma J J Langemeyer J M de Bakker 《Nederlands tijdschrift voor geneeskunde》1990,134(28):1364-1369
From 1980 to 1988 direct arrhythmia surgery was performed in 121 patients suffering from postinfarction drug-refractory ventricular tachycardia (VT). By 1986 the initially high in-hospital mortality of 26% (18 of 69 patients) had decreased to 1.9% (1 of 52 patients). The 3-year actuarial survival of patients operated since 1986 is 90%. From 1985 the results of surgical therapy of VT have improved: 86% of the patients remained arrhythmia-free without drugs; none died suddenly. Residual left ventricular function was related to the prognosis, but the interval between the last myocardial infarction and time of surgery or the surgical technique were not. These results demonstrate that direct surgery has become a valuable method in the treatment of postinfarction VT, at least in patients with sufficient residual left ventricular function. 相似文献
104.
Jorden M Veeneman Hermi A Kingma Frans Stellaard Paul E de Jong Dirk-Jan Reijngoud Roel M Huisman 《Nephrology, dialysis, transplantation》2004,19(6):1533-1541
BACKGROUND: The PNA (protein equivalent of nitrogen appearance) is used to calculate protein intake from urea kinetics. One of the essential assumptions in the calculation of PNA is that urea accumulation in haemodialysis (HD) patients is equivalent to amino acid oxidation. However, urea is hydrolysed in the intestine and the resulting ammonia could be used metabolically. The magnitude and dependence on protein intake of this process are unknown in HD patients. METHODS: Seven HD patients were studied twice, 1 week apart, on a similar protocol. After an overnight fast, patients fasted in the morning and received meals in the afternoon. On one day, amino acid oxidation was measured by infusion of L-[1-(13)C]valine. Urea production, measured from the dilution of [(13)C]urea, and urea accumulation, calculated from the increase in plasma urea concentration multiplied by the urea dilution volume, were measured during the other day. PNA was calculated using standard equations. RESULTS: Amino acid oxidation and urea production were not significantly different during fasting. Urea accumulation during fasting was significantly lower than both amino acid oxidation and urea production. Urea accumulation during feeding remained significantly lower than amino acid oxidation. PNA was equal to the average of the urea accumulation values during fasting and feeding. CONCLUSION: We conclude that during fasting, urea accumulation is not associated with amino acid oxidation or urea production. During meal intake, amino acid oxidation, urea production and urea accumulation show acutely an almost identical increase. PNA represents the average of fasting and fed urea accumulation and is lower than average amino acid oxidation or urea production. 相似文献
105.
Simultaneous gas-chromatographic determination of free and acetyl-conjugated polyamines in urine 总被引:1,自引:0,他引:1
G A van den Berg F A Muskiet A W Kingma W van der Slik M R Halie 《Clinical chemistry》1986,32(10):1930-1937
A capillary gas-chromatographic method with nitrogen-phosphorus detection is used to determine simultaneously urinary 1,3-diaminopropane, monoacetyl-1,3-diaminopropane, putrescine, monoacetylputrescine, cadaverine, monoacetylcadaverine, spermidine, N1-acetylspermidine, N beta-acetylspermidine, spermine, N1-acetylspermine, isoputreanine, N-(3-aminopropyl)pyrrolidin-2-one, and putreanine. The compounds are isolated by adsorption onto silica and converted into their methyl-heptafluorobutyryl derivatives. We give quality-control data and age-dependent "normal" values for urinary excretion of these analytes from 51 apparently healthy control subjects. Normal values for 31 adults are compared with those reported in the literature. Monoacetyl-1,3-diaminopropane and N1-acetylspermine are identified by mass fragmentography. We applied the method to monitor chemotherapeutic treatment of a patient with advanced non-Hodgkin's lymphoma; we identified by mass spectrometry N1,N12-diacetylspermine in this patient's urine. 相似文献
106.
107.
Vestibular evoked myogenic potentials (VEMPs) were measured in 22 unilateral Menière patients with monaural and binaural stimulation with 250 and 500 Hz tone bursts. For all measurement situations significantly lower VEMP amplitudes were on average measured at the affected side compared to the unaffected side. Unilateral Menière patients have, in contrast to normal subjects, asymmetric VEMPs, indicating a permanently affected vestibular (most likely otolith) system at the side of hearing loss. The diagnostic value of VEMP amplitude asymmetry measurement in individual patients is low, because of the large overlap of the VEMP amplitude asymmetry range for unilateral Menière patients with that for normal subjects. 相似文献
108.
I Kingma O A Smiseth I Belenkie M L Knudtson R P MacDonald J V Tyberg E R Smith 《The American journal of cardiology》1986,57(8):673-677
Nitroglycerin has been shown to cause a downward shift in the left ventricular (LV) pressure-volume relation in patients. To test the hypothesis that this shift is mediated by an alteration in pericardial pressure, 13 patients undergoing diagnostic cardiac catheterization were studied. LV and right ventricular (RV) pressure (micromanometers) and LV diameter (2-dimensional echocardiography) were measured simultaneously before and after sublingual administration of 0.3 to 0.6 mg of nitroglycerin. In the 11 patients with hemodynamic effects from nitroglycerin, mean LV end-diastolic pressure decreased from 12.7 +/- 5 mm Hg (mean +/- standard deviation) to 7.3 +/- 3 mm Hg (p less than 0.002) and mean RV end-diastolic pressure declined from 7.7 +/- 3 mm Hg to 5.0 +/- 1 mm Hg (p less than 0.001). However, nitroglycerin caused only a slight (6%) reduction in LV minor axis diameter, from 52 +/- 8 mm to 49 +/- 9 mm (p less than 0.05). Diastolic pressure-diameter plots constructed from early and late diastolic measurements demonstrated a downward shift in the relation. However, when RV end-diastolic pressure was used as an estimate of pericardial pressure (a procedure validated by studies in our laboratory), the transmural pressure-diameter points before and after administration of nitroglycerin defined a single curve. These observations are in keeping with the conclusions that nitroglycerin did not alter the elastic properties of the myocardium and that the decrease in LV end-diastolic pressure induced by nitroglycerin was primarily attributable to a reduction in external constraint. 相似文献
109.
Background:
Background: Different micro-organisms can be cultured from abdominal fluid obtained from patients with intra-abdominal infection resulting from a perforated digestive tract. We evaluated a cohort of patients with abdominal sepsis admitted to the intensive care with the aim of obtaining more insight into the type of microorganisms involved and the efficacy of treatment. 相似文献110.