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1.
OBJECTIVE: Visual symptoms are common in patients with preeclampsia, and are caused by various underlying pathological changes in the retina. Blurred vision may be one of these symptoms. We describe three cases in which the underlying retinal pathology of blurred vision was clarified using optical coherence tomography (OCT), a novel, non-invasive ophthalmic imaging technique that provides micrometer-scale resolution images of the human retina. METHODS: Three patients with preeclampsia complained of blurred vision postpartum. In all cases, ophthalmoscopy was performed at the bedside, followed by the assessment of best corrected visual acuity, slit-lamp biomicroscopy, fluorescein angiography (FLA), and OCT. In all cases, the presence of central visual defects was examined by an Amsler-grid. RESULTS: In one case, the symptoms were bilateral. In all affected eyes, the patients complained of a relative central scotoma. Ophthalmoscopy showed edema in the affected maculae, while OCT examination clarified a serous neurosensory detachment of the macula. In one case, a neurosensory detachment was also detected in the papillomacular region of a fellow eye with no symptoms. In two cases, FLA was performed, but only in one case could we detect late leakage and subretinal exudates. The serous detachments observed showed total resolution in all cases within 5 to 10 weeks, with restoration of visual acuity. CONCLUSION: In patients with preeclampsia, OCT may provide a useful method for the precise assessment of retinal changes, distinguishing retinal edema from serous neurosensory detachments. This finding may help to clarify the pathophysiological circulatory changes seen in preeclampsia.  相似文献   
2.
Renal excretion of endothelin in children   总被引:1,自引:0,他引:1  
Endothelin (ET) is a peptide with profound vasoconstrictive potential. First isolated from porcine endothelial cell supernatant, it is produced also by smooth muscle, epithelial and circulating cells. Besides vasoconstriction, a wide spectrum of biological activities of ET (via activation of membrane receptors) has been described. These include regulation of other hormones and neurotransmitters, cellular growth and proliferation, bronchoconstriction, and, in the kidney, natriuresis and water diuresis. ET exerts its effects mainly in an autocrine and paracrine fashion. A high concentration of ET is found in urine, compared with plasma originating mainly from the kidney itself. In this review we focus on the role of urinary excretion of ET in children. ET excretion was determined under different physiological and pathological conditions. In premature infants and newborns, the daily excretion of ET (corrected for body surface) was higher than in older children; it was constant, and comparable to the values in healthy adults after the age of 2 years. Renal ET excretion correlated positively with urine flow in both healthy and sick children. Conditions with tubular and/or collecting duct cell damage, such as severe hypoxia, hemolytic-uremic syndrome, renal transplantation, diabetes mellitus, chronic renal failure, and contrast media cytotoxicity were characterized by elevated urinary excretion of ET. In conclusion, the renal excretion of ET is influenced by several factors, probably reflecting the intrarenal ET production. ET has a low specificity with regard to renal injury. Received May 7, 1996; received in revised form January 14, 1997; accepted January 17, 1997  相似文献   
3.
Twenty-four-hour blood pressure and heart rate measurements were carried out in 14 newly diagnosed diabetics and in 28 diabetics with 5–13 years' duration of the disease; 8 healthy children were used as controls. Mean arterial blood pressure increased at night in 5, decreased slightly (less than 10%) in 5 and decreased markedly (more than 10%) in 18 diabetics with longer duration of the disease. The diurnal-nocturnal differences in heart rates were significantly lower in diabetics with relative "nocturnal hypertension" compared to the control group ( p < 0.05). A significant negative correlation was found between maximal arterial blood pressure during physical exercise and the diurnal-nocturnal differences in mean arterial blood pressure in diabetics ( r =−0.58; p < 0.02). In conclusion, we found elevated nocturnal blood pressure in a subgroup of children with longer duration of diabetes and without increased albumin excretion. However, longitudinal studies of blood pressure profiles are needed to identify the candidates for diabetic vasculopathy among diabetic children.  相似文献   
4.
K Jellinek  T Tulassay  T Verebély  W Rascher 《Orvosi hetilap》1989,130(43):2299-300, 2303-4
Authors investigated the concentration changes of arginine vasopressin (AVP) and of atrial natriuretic peptide (ANP) in plasma. The renal characteristics of water- and sodium metabolism in the first 24 hours of the postoperative period in 11 children operated with acute appendicitis have been studied. Crystalloid infusion was applied in 60 ml/kg/24 h dose, in 5 cases however, 1 g/kg albumin vas also administered during the operation. In children getting crystalloid infusion (group "A") the initial AVP value was 29.9 +/- 8.8 pg/ml, which further increased to 58.2 +/- 15.2 pg/ml (p 0.05) by the 6. postoperative hour and even in the 24. hour it remained above the physiological value (19.9 +/- 5.3 pg/ml). During the observation time significant Na- and water retention developed. The albumin administration (group "B") stopped the further increase of AVP values, the Na-household remained in equilibrium and the water retention developed only in smaller degree. The ANP plasma concentration of both groups was in the normal range and did not change during observation time. Our data show that for the postoperative water retention first of all the increased AVP activity is responsible. The more intensive AVP secretion may be induced by the relative intravascular hypovolemia since by enhancing the plasma volume the further increase of postoperative hormone activity could be prevented.  相似文献   
5.
BACKGROUND AND AIM: Determination of the local densities of Helicobacter pylori and its genotypic variations in gastric biopsy specimens by using novel real-time PCR-based methods could support the precise diagnosis and understanding of H. pylori infections. METHODS: Serial dilutions of H. pylori (0.016-16 microg/microl), control, bacterial, and human DNA samples were prepared. Fresh-frozen gastric biopsy specimens were taken from 103 patients, and the DNA was isolated. Quantitative determination of the ureaseA gene using hybridization probes with parallel evaluation of an internal human control gene (beta-globin) was performed by real-time PCR. CagA and VacA s1 genotypic characterizations were also performed. The data were compared with urea breath test (UBT), histology, and serological testing. RESULTS: The presence of H. pylori could be detected by ureaseA-fluorescence energy transfer (53%), UBT (51%), serological testing (48%), and histology (52%) when compared with the gold standard (54%). A significant correlation was found between the quantitative real-time ureaseA/beta-globin ratio-based H. pylori frequency and the UBT results (P<0.01). Significantly increased bacterial density was found in the erosions when compared with the healthy part of the antrum and corpus (P<0.01). Real-time PCR VacA s1 results were in significant correlation (P<0.01) with those of serological tests, but CagA results were not. The genomic profiles (VAC/GAC) were different in 13.7% of the cases, which involved three different locations in the stomach. CONCLUSION: Real-time PCR was the most reliable method for H. pylori diagnosis. Furthermore, quantification and genotyping could also be performed using this technique. The density of H. pylori was significantly increased in macroscopic erosions.  相似文献   
6.
7.
The efficacy of pirenzepin--of anticholinergic effect--and the H2-receptor blocking cimetidine has been studied in duodenal ulcer with random, double blind fashion. Recurrence examinations were carried out 6 and 12 months following the treatment. 50 patients were given pirenzepin and 50 cimetidine. The average age of the patients was 44.5 and 43.8 years respectively. Of them 60 (24 + 36) were men and 40 (26 + 14) women. At the start, 6 weeks following the start 6 and 12 months after the finishing of the treatment gastroscopy was performed. In the course of the six-week-long treatment 38 (76%) of the pirenzepin taking patients and 36 (72%) of the cimetidine taking patients recovered. No significant difference was found between the efficacy of the both treatments. In the respect of the half and one year recurrence, no significant difference was observed between the two patient groups. Ten of the patients taking pirenzepin and 4 of those taking cimetidine complained of side effects. Dryness of mouth, visual disturbance in the former group and constipation in the latter one. On the basis of the examinations both secretion inhibitors were found equally suitable for the therapy of duodenal ulcer.  相似文献   
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9.
Chronic inflammation is an important risk factor for the development of cancers. The link between chronic inflammation and the risk of developing cancer is now well established. At least 20% of all cancers arise in association with infection and chronic inflammation. Inflammation and cancer are linked both along intrinsic (driven by genetic events causing malignancy) and extrinsic (driven by inflammatory conditions predisposing to tumor) pathways. Proteinases are key contributors to the breakdown and reconstitution of extracellular matrix components in physiological processes and pathological conditions, including destructive diseases and tumor progression. Matrix metalloproteinases are especially essential in the complex process of coregulation between cellular components of the tumor environment, and they are considered as potential diagnostic and prognostic biomarkers in many types and stages of cancer. Although the link between chronic inflammation, proteinases and risk of developing cancer is now well established, several open questions remain. The most exciting challenge is to find the best approach to target cancer-associated inflammation in patients with cancer. With respect to matrix metalloproteinases, the development of a new generation of selective inhibitors is a promising area of research.  相似文献   
10.
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