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41.
OBJECTIVE: An evaluation of growth hormone (GH) testing for GH deficiency (GHD) in childhood is confounded by the lack of a world-wide consensus on the definition of GHD. Although a single GH test remains the most powerful biochemical tool in the evaluation of a child with growth failure, the test remains far from ideal. Withdrawal of somatostatin (SS) infusion is followed by a rebound rise of GH thought to be mediated by endogenous GH-releasing hormone (GHRH) function. This study was designed to compare the GH response to 90 min SS infusion in children with normal GH secretion versus children with GH deficiency. METHODS: Ten children with GHD and 10 healthy controls (NC) have been evaluated for GH response to somatostatin infusion withdrawal (SSIW) and compared with response of two provocative tests, glucagon plus propranolol test and L-Dopa test. All children received constant infusion of somatostatin for 90 min (3 microg/kg per h, Stilamin, Serono, Aubonne, Switzerland). In order to determine GH, blood samples were obtained 90 min before the SS infusion and 0, 15, 30, 45, 60, 75, and 90 min after the cessation of infusion. RESULTS: Growth hormone peak levels with SSIW were significantly lower in GH deficient children than in healthy children (2.5 +/- 1.2 ng/dL, vs 21.9 +/- 5.3 ng/dL, respectively, P < 0.01). No adverse effects were observed during or after somatostatin infusion. CONCLUSION: In the present study, SSIW elicited a significant GH rise in healthy children but not in children with GH deficiency. Although further controlled studies using more data are necessary to expand these findings, the results suggested that children with GH deficiency can be reliably discriminated from healthy children by SSIW.  相似文献   
42.
The effect of combined spinal epidural (CSE) anaesthesia and size of spinal needle on postoperative hearing loss after elective caesarean section The exact aetiology of vestibulocochlear dysfunction after spinal anaesthesia is unknown. Low‐frequency hearing loss occurs after spinal anaesthesia. The aim of this study was to investigate the effects of combined spinal–epidural (CSE) anaesthesia and size of spinal needle on vestibulocochlear dysfunction, using pure tone audiometry performed pre‐ and on the first and the second day postoperatively. Forty‐five patients who were to undergo elective caesarean section were evaluated. In group I, CSE anaesthesia (18 G Tuohy, 25 G Whitacre pencil‐point‐design spinal needles) was performed in 15 patients. In group II, spinal anaesthesia was performed in 15 patients with 25 G Whitacre pencil‐point‐design spinal needles and, in group III, spinal anaesthesia was performed in 15 patients with 22 G Whitacre pencil‐point‐design spinal needles. In the pre‐ and on the first and the second day postoperatively, the pure tone audiogram was performed in the audiology laboratory of our hospital, using a calibrated Kamplex Diagnostic Audiometer AC 40 in a noise‐free room. When the CSE anaesthesia group and 22 G spinal group were compared for change in hearing between the pre‐ and postoperative periods, a statistically significant difference was observed at R‐right ear 125 Hz (P < 0.025) and at L‐left ear 125 Hz (P < 0.023), and at L‐left ear 1000 Hz (P < 0.036) and at R‐right ear 1500 Hz (P < 0.006), and at L‐left ear 1500 Hz (P < 0.022). At other frequencies, the difference was insignificant. When the CSE anaesthesia group and 25 G spinal group were compared for change in hearing between the pre‐ and postoperative periods, no statistically significant difference was detected at any frequency tested. When 22 G spinal group and 25 G spinal group were compared for change in hearing between the pre‐ and postoperative periods, there was some hearing loss at low frequency, although this difference did not reach statistical significance. The positive correlation of low‐frequency hearing loss and increased pressure in the epidural space (which decrease the risk of cerebrospinal fluid leakage through the dura) suggests that cerebrospinal fluid leakage via the spinal puncture hole is not the only factor involved. Perioperative fluid replacement alone may not prevent hearing loss but CSF loss through the dural puncture site should also be prevented.  相似文献   
43.
The objectives of this study were to establish whether there is an obvious difference between intact mucosa and abraded mucosa of the middle-ear cavity in respect to the potential side effects from the application of absorbable gelatine sponge (Gelfoam) and to investigate if Gelfoam combined with corticosteroid ointment (cortimycine, sterile 1% hydrocortisone acetate) can reduce the occurrence of these effects. Twenty Albino rats were used in the study. These animals were divided into four groups, with ten ears in each group. In group A, the middle-ear mucosa was kept intact, and Gelfoam was inserted into the middle-ear cavity. In group B, the middle-ear mucosa was abraded, and Gelfoam was inserted. In group C, Gelfoam with corticosteroid was implanted over the intact mucosa, and in group D, the mucosa was abraded prior to the insertion of Gelfoam with corticosteroid. The changes were evaluated 8 weeks postoperatively. In group A, there was a minimal increase in fibroblastic activity, vascular proliferation with mild to moderate fibrosis and all but two tympanic membranes were perfectly normal. However, in group B, we encountered a significant increase in fibroblastic activity, vascular proliferation and fibrosis, and we observed that all tympanic membranes were moderately to severely thickened. These histopathologic changes related to Gelfoam were noted to be decreased in group C and especially in group D. As previously reported in the literature, Gelfoam was found to promote the formation of connective tissue in the middle-ear cavity regardless of the status of the mucosa. The unwanted effects of this material may be decreased if it is combined with corticosteroids in the middle-ear cavity.  相似文献   
44.
Sprengel deformity is a rare orthopedic condition that is associated with functional and cosmetic impairment. Results of orthopedic procedures are usually inconsistent and cosmetic results are far from satisfactory in these patients. A silicone-gel-filled calf prosthesis was used to correct the shoulder contour in a patient with Sprengel deformity. Cosmetically the deformity can be restored by using a calf implant for patients in whom orthopedic procedures are not likely to yield a satisfactory outcome.  相似文献   
45.
Stress and sulfite can stimulate numerous pathways leading to an increased production of free radicals which generate a peroxidation cascade producing lipid peroxidation, protein oxidation, DNA damage and cell death, and contribute to the occurrence of pathologic conditions. The purpose of our study was to investigate the effects of stress and sulfite on visual evoked potentials (VEPs) and to examine the relationship between lipid peroxidation and VEP changes. Forty male wistar rats, aged three months were used. They were equally divided into four groups: control (C), the group exposed to restraint stress (R), the group treated with sulfite (S) and the group exposed to stress and treated with sulfite (RS). Chronic restraint stress was applied for 21 days (1h/day) and sodium metabisulfite (520 mg/kg/day) was given by gavage for the same period. All latencies of VEP components were prolonged in the R, S and RS groups with respect to the C group. Brain and retina TBARS levels were found to be increased in those groups compared to the C group. Our results strongly suggest that the latency prolongations of all VEP components may have resulted from the enhancement of lipid peroxidation. Correlation analysis between brain and retina TBARS levels and VEP latencies also support this conclusion. Our data in regard to latency prolongations of all VEP components in the stress group exposed to sulfite, reflected an additive effect of sulfite toxicity on VEP components. Therefore it could be suggested that chronic exposure to stress and sulfite together is associated with a considerable health risk.  相似文献   
46.
Segmental myoclonus is described as the involuntary contractions of contiguous muscles innerved by the brain stem or by spinal cord. The underlying causes of segmental myoclonus in children are demyelinating diseases and intrinsic tumors. Here, we report a case who was presented with segmental myoclonus on his left arm and later diagnosed as atypical monosymptomatic presentation of acute disseminated encephalomyelitis (ADEM). The case represents the first in the literature in which ADEM is considered as the possible cause of segmental myoclonus. Our findings demonstrate that: (i) in focal movement disorders such as segmental myoclonus, a careful neuroradiological examination of the neuroanatomical region for the possible presence of organic lesions might be rewarding, (ii) ADEM might be one of the potentially reversible causes of myoclonus.  相似文献   
47.
Mycobacterium tuberculosis (H(37)R(v))-infected guinea-pig model was used to investigate the effect of water extract of propolis (WEP). After subcutaneous inoculation of tubercle bacilli, each animal received oral WEP (n=9), isoniazid (n=5) or saline (n=6) as placebo and were sacrificed 30 days later. Formation of necrosis was less prominent in the group treated with WEP, but was not statistically significant (P>0.05). The granuloma formation in the same group was more prominent than the placebo and isoniazid groups; however, this finding failed to reach statistical significance by the Kruskal-Wallis test (P>0.05). These findings suggest that Turkish WEP may have a limited effect on the development of tuberculosis infection in this guinea-pig model.  相似文献   
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