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71.
Twenty-four-hour ambulatory blood pressure profiles in pediatric patients after renal transplantation 总被引:2,自引:2,他引:0
Nicolaus Lingens Eva Dobos Klaus Witte Christopher Busch Björn Lemmer Günther Klaus Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1997,11(1):23-26
Ambulatory blood pressure monitoring was applied in 27 pediatric patients aged 6.3 – 24.3 (median 15.0) years who had been
transplanted 1.5 – 8.4 years previously. Daytime values were compared with the mean of 10 concomitant casual blood pressure
recordings. At the time of the study, antihypertensive drugs were given to 17 patients. Inulin clearance ranged from 18 to
116 (median 66) ml/min per 1.73 m2. Ambulatory blood pressure monitoring confirmed hypertension or normotension determined by casual blood pressure measurements
in 63% of patients. The physiological nocturnal dip in blood pressure was attenuated or reversed in 8 of 27 patients. It was
reduced in all 3 patients with renal artery stenosis of the graft, in 3 of 4 patients with chronic rejection, in the only
patient with recurrent focal segmental glomerulosclerosis, and in 1 of 6 patients with past acute rejection. The dipping was
not related to inulin clearance. In conclusion, casual blood pressure measurements do not accurately reflect blood pressure
in pediatric patients transplanted more than 1.5 years previously. A reduced nocturnal dip in blood pressure may indicate
an underlying renovascular or renoparenchymal pathology. Ambulatory blood pressure monitoring should regularly be applied
in patients with renal transplants.
Received May 23, 1995; received in revised form June 18, 1996; accepted June 20, 1996 相似文献
72.
C Sch?fl K S Cuthbertson C A Walsh C Mayne P Cobbold A von zur Mühlen R D Hesch J A Gallagher 《Journal of bone and mineral research》1992,7(5):485-491
ATP released from damaged cells or by controlled secretion could be an important factor in the formation or remodeling of bone. In a variety of other tissues ATP has been shown to control cellular processes by acting on P2-purinoceptors and activating the calcium signaling pathway. Here we demonstrate for the first time that extracellular ATP increases the intracellular free calcium [Ca2+]i concentration in normal human osteoblasts and in SaOS-2 cells, a human osteosarcoma-derived cell line, but not in ROS 17/2.8 cells. The ATP-induced increase in [Ca2+]i was dose dependent, and the concentrations of ATP required were similar to those reported to regulate cellular functions in other cell types. Although ATP is metabolized rapidly by bone cells, the effects on [Ca2+]i appeared to be mediated directly by ATP rather than one of its metabolites. Adenosine 3-thiotriphosphate, a nonhydrolyzable analog of ATP, induced similar changes in [Ca2+]i. This indicates that P2-purinoceptors are present on osteoblast-like cells and that extracellular ATP from various sources might be an important factor in the regulation of osteoblast functions. 相似文献
73.
74.
75.
Emine Sözeri Dietrich Feist Hans Ruder Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1997,11(3):307-311
Renal lesions have repeatedly been described in Wilson’s disease (WD). We investigated the excretion of total protein, albumin,
low (LMW) and high molecular weight (HMW) proteins, N-acetyl-β-D-glucosaminidase (NAG), and calcium, as well as creatinine clearance, in 24-h urine samples of 41 patients with WD aged 6 – 37
(mean 17) years who had been treated for a period of 0 – 15 (mean 4.5) years with D-penicillamine (900 mg/day). The amount of all protein excreted was significantly increased compared with controls, 39% of
patients presenting with total proteinuria more than two standard deviations from the mean of controls. The changes in protein
excretion depended on the duration of treatment. LMW proteinuria was elevated almost exclusively in the first 2 years after
the start of treatment, indicating early tubular damage. This is supported by an initially high excretion of β2-microglobulin, NAG, and calcium. Increased excretion of HMW proteins, including albumin, persisted over longer periods, which
suggests glomerular injury in some patients, possibly related to the use of D-penicillamine. Creatinine clearance remained roughly within normal limits. We propose that renal function should regularly
be checked in patients with WD.
Received October 26, 1995; received in revised form August 27, 1996; accepted September 20, 1996 相似文献
76.
Summary. The ACL in the rabbit is innervated by three types of nerve fibres. These subserve vasoconstriction, nociceptive and proprioceptive
purposes. The aim of this paper was to investigate the revascularisation and reinnervation of cyropreserved ACL allografts
in 22 New Zealand white rabbits. Cyropreserved grafts were used as they may excite less host immune response. Both microangiographic
and immunohistochemical methods were used. We found that cryopreserved allografts exhibited little immune response, revascularisation
was considerable by the 24th postoperative week and reinnervation was essentially complete by then. No mechanoreceptors were
found in ACL allografts. In rabbits, the anatomical basis for the participation of ACL allografts in sensorimotor reflexes
is not given before the twelfth week after transplantation.
Accepted: 11 May 1995 相似文献
Résumé. Nous avons examiné par méthodes micro-angiographiques et immuno-histo-chimiques la revascularisation et l’innervation d’un allogreffon cryopréservé (os – ligament croisé antérieur – os), chez 22 lapins de Nouvelle Zélande. Au sein de la greffe, existe une hypervascularisation maximale à 6 semaines, persistante à 12 semaines et se normalisant 24 semaines après la transplantation. Le panicule adipeux du genou était une source importante pour la revascularisation du greffon. L’immuno-histo-chimie a montré la présence de 3 types de fibres nerveuses au sein du ligament croisé: des afférents sensoriels mécano-réceptifs, des afférents sensoriels nociceptifs et des efférents sympathiques vaso-moteurs. Les contr?les ont montré l’existence de plusieurs fibres des 3 types de nerf; les terminaisons sensitives étaient toutes des corpuscules de Ruffini. Il n’y avait pas de fibre nerveuse au sein de l’allogreffe du ligament croiséà 3 et 6 semaines après la transplantation. Des fibres d’aspect cicatriciel étaient détectées à 12 semaines, tandis que des contr?les plus tardifs montraient un nombre et une distribution presque normale des filets nerveux. Aucun récepteur mécanique ne fut trouvé dans l’allogreffe. Chez le lapin, les bases anatomiques de la participation sensitivo-motrice de l’allogreffe du ligament croisé antérieur n’existent pas avant la 12ème semaine après la transplantation.
Accepted: 11 May 1995 相似文献
77.
78.
Horst Claassen Frank Hornberger Katharina Scholz-Ahrens Michael Schünke Jürgen Schrezenmeir Bodo Kurz 《Annals of anatomy》2002,184(2):141-148
Clinical observations have suggested that estrogens are involved in the pathogenesis of postmenopausal osteoarthritis (OA). However, positive and negative associations between the incidence of OA and serum estrogen concentrations have been reported. In contrast to this, osteoporosis is regarded as a disease with a strong estrogen-dependent component. Moreover, there is an interaction between estrogen and calcium deficiency: calcium supplementation potentiates the effect of estrogen therapy. The present study was designed to investigate how estrogen deficiency affects the articular cartilage depending on calcium supply. The distribution of different types of glycosaminoglycans and collagens can be used as an indicator for extracellular matrix changes induced by estrogen deficiency. Different levels of dietary calcium were therefore fed to intact and ovariectomized G?ttingen miniature pigs for one year before articular cartilage was harvested. The histochemical staining for heavy sulfated glycosaminoglycans in the extracellular matrix of ovariectomized miniature pigs, especially of those fed with a low calcium diet, was stronger in comparison to intact animals. In intact animals type II-collagen was immunodetected in all zones of unmineralized and mineralized articular cartilage, while immunostaining for this protein was negative to weak in the deep radiated fiber zone of ovariectomized minipigs. These results suggest that the synthesis of heavy sulfated glycosaminoglycans and immunohistochemically detectable type II-collagen is possibly influenced by estrogen deficiency. In conclusion, under estrogen deficiency, the extracellular matrix of articular cartilage underwent similar changes to those observed in physiologically aging cartilage where keratan sulfate is increased as a heavy sulfated glycosaminoglycan. 相似文献
79.
Reepithelialization of experimental scalds effected by topically applied superoxide dismutase: controlled animal studies 总被引:1,自引:0,他引:1
Karola Vorauer-Uhl MD ; Eckhard Fürnschlief MD ; Andreas Wagner MD ; Boris Ferko MD ; Hermann Katinger MD 《Wound repair and regeneration》2002,10(6):366-371
Highly reactive metabolites, such as oxygen free radicals, initiate a cascade of inflammatory processes in thermally damaged skin, leading to enhanced tissue loss and delayed wound healing. The extent of tissue necrosis in the zone of stasis is of prognostic significance in the wound healing process. In this study, the effect of oxygen free radical removal by recombinant human-Cu/Zn-superoxide dismutase, given in three different formulations during the inflammatory postburn phase and wound repair, was examined. Recombinant human superoxide dismutase was either injected directly into the lesions, spread as enzyme-containing gel onto the burned tissue, or encapsulated into liposomes consisting of 1,2 dipalmitoy-sn-glycero-3-phosphocholine, cholesterol and stearylamine, suspended into a hydrophilic gel and administered to burned animals immediately after trauma. Controls were treated with plain gel or kept untreated. Edema formation, size of lesions, deepening of necrosis, and reepithelialization were examined. Results indicate that superoxide dismutase treatment resulted in reduced and faster recruitment of edema formation, smaller wound sizes, and minor tissue necrosis compared to the controls, thus resulting in significantly faster reepithelialization after 3 weeks. These animal studies on the efficacy of liposomal oxygen free radical scavenger showed accelerated wound healing in all parameters tested. 相似文献
80.