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861.
In recurrent calcium stone formers interfering factors or changes in receptor sensitivity may alter the interrelationships among calcium-regulating hormones, and hormonal behavior often does not fit with the theoretical assumptions. The vitamin D system appears to have the most important metabolic and clinical effects. Abnormal up-regulation of the synthesis of calcitriol and the consequent parathyroid hormone (PTH) suppression can induce hypercalciuria. Consequently, the hypocalciuric effect of thiazide would be caused by an enhanced response to PTH and by a reduction in 1,25(OH)2-vit D. A negative role of vitamin D on the skeleton has been observed in the presence of a negative calcium balance. Moreover, vitamin D also plays a role in urine oxalate excretion. PTH seems not to be directly stimulated in hypercalciuria and recurrent calcium nephrolithiasis, and patients with hyperparathyroidism and recurrent calcium nephrolithiasis show a similar degree of bone demineralization, irrespective of the presence of absence of the so-called 'primary hyperparathyroidism.' Calcitonin plays a contributory role in the pathogenesis of recurrent calcium nephrolithiasis that seems to be strictly related to dietary calcium intake. A higher sensitivity of thyroid C cells, particularly in absorptive hypercalciuric patients, could be related to the pathogenesis of hypercalciuria and contribute to its persistence. 相似文献
862.
A Avogaro F Piarulli A Valerio M Miola M Calveri P Pavan P Vicini C Cobelli A Tiengo L Calò S Del Prato 《Canadian Metallurgical Quarterly》1997,46(6):1040-1046
Endothelium-dependent and -independent vascular responses were assessed in 10 NIDDM patients and 6 normal subjects with no evidence of atherosclerotic disease. Changes in forearm blood flow and arteriovenous (AV) serum nitrite/nitrate (NO2-/NO3-) concentrations were measured in response to intra-arterial infusion of acetylcholine (ACh) (7.5, 15, 30 microg/min, endothelium-dependent response) and sodium nitroprusside (SNP) (0.3, 3, 10 microg/min, endothelium-independent response). Insulin sensitivity (determined by minimal model intravenous glucose tolerance test) was lower in NIDDM patients (0.82 +/- 0.20 vs. 2.97 +/- 0.29 10(4) min x microU(-1) x ml(-1); P < 0.01). Baseline forearm blood flow (4.8 +/- 0.3 vs. 4.4 +/- 0.3 ml x 100 ml(-1) tissue x min(-1); NS), mean blood pressure (100 +/- 4 vs. 92 +/- 4 mmHg; NS), and vascular resistance (21 +/- 1 vs. 21 +/- 1 units; NS), as well as their increments during ACh and SNP, infusion were similar in both groups. No difference existed in baseline NO2-/NO3- concentrations (4.09 +/- 0.33 [NIDDM patients] vs. 5.00 +/- 0.48 micromol/l [control subjects]; NS), their forearm net balance (0.31 +/- 0.08 [NIDDM patients] vs. 0.26 +/- 0.08 micromol/l x 100 ml(-1) tissue x min(-1); NS), and baseline forearm glucose uptake. During ACh infusion, both NO2- and NO3- concentrations and net balance significantly increased in both groups, whereas glucose uptake increased only in control subjects. When data from NIDDM and control groups were pooled together, a correlation was found between the forearm AV NO2- and NO3- differences and blood flow (r = 0.494, P = 0.024). On the contrary, no correlation was evident between NO2- and NO3- concentrations or net balance and insulin sensitivity. In summary, 1) no difference existed in basal and ACh-stimulated NO generation and endothelium-dependent relaxation between uncomplicated NIDDM patients and control subjects; 2) in both NIDDM and control groups, forearm NO2- and NO3- net balance following ACh stimulation was related to changes in the forearm blood flow; and 3) ACh-induced increase in forearm blood flow was associated with an increase in glucose uptake only in control subjects but not in NIDDM patients. In conclusion, our results argue against a role of impaired NO generation and blood flow regulation in determining the insulin resistance of uncomplicated NIDDM patients; rather, it supports an independent insulin regulation of hemodynamic and metabolic effects. 相似文献
863.
E Arrigoni A Caprez R Amadò H Neukom 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1984,178(3):195-198
The present paper describes a simple method for the determination of the insoluble and soluble dietary fibres in food. In a first step, starch and proteins are removed by enzyme treatment. The insoluble dietary fibres are determined gravimetrically after centrifugation and washing of the residue with water, ethanol, acetone and diethyl ether. The water-soluble dietary fibres are recovered from the supernatant liquid of the centrifugation by dialysis, freeze-drying, and subsequent weighing. The method has been used for the determination of dietary fibres in by-products from the industry. 相似文献
864.
Assessed filtering and the ability to narrow attentive focusing among 30 persons with schizophrenia (mean age 44 yrs), 14 persons with major depression (MDD; mean age 46 yrs), and 20 normal persons (mean age 46 yrs). Conditions varied with the presence of distracters and their proximity to a target, and the presence of a window cue used to facilitate filtering. Among both the persons with schizophrenia and those with no psychiatric history, RTs were longest with distracters located closest to targets, and performance was not related to the presence of the window. The performance of persons with MDD was adversely affected with distracters located closest to targets, and facilitated with the presence of the window. These findings are consistent with relatively intact filtering and focusing in schizophrenia, and a filtering deficiency in MDD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
865.
C Cristòfol B Pérez M Pons JE Valladares G Martí M Arboix 《Canadian Metallurgical Quarterly》1998,709(2):310-314
Linear IgA disease (LAD) is characterized by circulating and tissue-bound IgA antibodies against heterogeneous antigens in the cutaneous basement membrane zone. In most cases the cause is unknown, but a minority of cases has been drug induced. We report a 76-year-old man who developed an acute blistering eruption following high-dose penicillin treatment for pneumococcal septicaemia. Indirect immunofluorescence demonstrated dermal binding IgA antibodies, and Western blotting of serum showed reactivity with a 250 kDa dermal antigen corresponding to collagen VII of anchoring fibrils. Indirect immunoelectron microscopy showed antibody labelling in the lamina densa and sublamina densa zone. This is one of the few cases of drug-induced LAD in which the target antigen profile has been characterized, and the first in which the antigen has been shown to correspond to collagen VII. 相似文献
866.
867.
MP Hilbers A Rossi A Finazzi-Agrò GA Veldink JF Vliegenthart 《Canadian Metallurgical Quarterly》1994,1211(2):239-242
A case of intramedullary neuroschistosomal granuloma in a 15-year-old girl is reported. Despite the fact that Saudi Arabia is endemic for schistosomiasis, neuroschistosomiasis has rarely been reported from that country. A review of the literature on the incidence, pathogenesis, clinical patterns and management of neuroschistosomiasis, particularly myelopathy, is given. 相似文献
868.
869.
Adele Carradò Heinz‐Guenter Brokmeier Thilo Pirling Robert Charles Wimpory Norbert Schell Heinz Palkowski 《Advanced Engineering Materials》2013,15(6):469-475
The residual stress state and the texture in Cu‐tubes, drawn without a plug under controlled laboratory conditions, are presented. Neutron stress determination confirms a stress gradient from the outer to the inner surface of the tube walls. High energy X‐rays were used to analyze the texture gradient around the perimeter of the tubes as well as over the wall thickness. Anisotropic flow during tube processing results in texture variations described by ODF‐analysis. 相似文献