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31.
This study evaluated factors influencing fracture (n = 197) and osteotomy (n = 200) healing in children with moderate to severe OI. Pamidronate treatment was associated with delayed healing after osteotomy, but not after fracture. The data suggest that both pamidronate and mechanical factors influence bone healing in this cohort. INTRODUCTION: Intravenous pamidronate is widely used to treat children with moderate to severe osteogenesis imperfecta (OI). However, the effect of this treatment on bone healing is not well characterized. We therefore retrospectively analyzed the healing of lower limb fractures and osteotomies in children with moderate to severe OI, both before and after the start of pamidronate treatment. MATERIALS AND METHODS: Bone healing was evaluated on standard radiographs after 197 lower limb fractures (132 femur and 65 tibia) in 82 patients (age at fracture, 0.0-19.9 years) and 200 intramedullary rodding procedures in 79 patients (age at surgery, 1.2-19.8 years). Delayed healing was diagnosed when a fracture or osteotomy line was at least partially visible 12 months after the event. RESULTS: Delayed fracture healing was observed more frequently during than before pamidronate treatment. However, the effect of pamidronate was no longer significant when age differences were taken into account (odds ratio [OR], 1.76; 95% CI, 0.61-5.10). Better mobility status was a strong independent predictor of delayed healing after fractures that occurred during pamidronate treatment. After osteotomies, delayed healing was more frequent when pamidronate had been started before surgery (OR, 7.29; 95% CI, 2.62-20.3), and this effect persisted after adjustment for multiple confounders. During pamidronate treatment, older age (OR per year of age, 1.25; 95% CI, 1.06-1.47) and osteotomy of the tibia (OR, 3.51; 95% CI, 1.57-7.82) were independent predictors of delayed healing. CONCLUSIONS: This study suggests that pamidronate therapy is associated with delayed healing of osteotomy sites after intramedullary rodding procedures. Better mobility status, but not pamidronate treatment, seems to be predictive of delayed healing after fractures.  相似文献   
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Management of an indeterminate pulmonary nodule is a diagnostic challenge that commonly confronts primary care physicians and specialists. Patients often present with this radiographic finding in the course of an unrelated medical evaluation. We examined our institution's experience with percutaneous biopsy of lung nodules to determine the impact of this procedure on overall patient care. Although significant complications are uncommon, the expedience of percutaneous lung biopsy often supplants a surgical opinion prior to initiation of therapy without added diagnostic benefit or cost-savings. Hence, we caution practitioners to use this technique as an adjunct to diagnosis and not a substitute for multidisciplinary care.  相似文献   
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OBJECTIVE Protein hypercatabolism and preservation of fat depots are hallmarks of critical illness, which is associated with blunted pulsatile GH secretion and low circulating IGF-I, TSH, T4 and T3. Repetitive TRH administration is known to reactivate the pituitary-thyroid axis and to evoke paradoxical GH release in critical illness. We further explored the hypothalamic-pituitary function in critical illness by examining the effects of GH-releasing hormone (GHRH) and/or GH-releasing peptide-2 (GHRP-2) and TRH administration. PATIENTS AND DESIGN Critically ill adults (n=40; mean age 55 years) received two i.v. boluses with a 6-hour interval (0900 and 1500 h) within a cross-over design. Patients were randomized to receive consecutively placebo and GHRP-2 (n=10), GHRH and GHRP-2 (n=10), GHRP-2 and GHRH+GHRP-2 (n=10), GHRH+GHRP-2 and GHRH+GHRP-2+TRH (n=10). The GHRH and GHRP-2 doses were 1μg/kg and the TRH dose was 200μg. Blood samples were obtained before and 20, 40, 60 and 120 minutes after each injection. MEASUREMENTS Serum concentrations of GH, T4, T3, rT3, thyroid hormone binding globulin (TBG), IGF-I, insulin and cortisol were measured by RIA; PRL and TSH concentrations were determined by IRMA. RESULTS Critically ill patients presented a striking GH response to GHRP-2 (mean±SEM peak GH 51±9 μg/l in older patients and 102±2μg/l in younger patients; P=0.005 vs placebo). The mean GH response to GHRP-2 was more than fourfold higher than to GHRH (P=0.007). In turn, the mean GH response to GHRH+GHRP-2 was 2.5-fold higher than to GHRP-2 alone (P=0.01), indicating synergism. Adding TRH to the GHRH+GHRP-2 combination slightly blunted this mean response by 18% (P=0.01). GHRP-2 had no effect on serum TSH concentrations whereas both GHRH and GHRH+GHRP-2 evoked an increase in peak TSH levels of 53 and 32% respectively. The addition of TRH further increased this TSH response < ninefold (P=0.005), elicited a 60% rise in serum T3 (P=0.01) and an 18% increase in T4 (P=0.005) levels, without altering rT3 or TBG levels. GHRH and/or GHRP-2 induced a small increase in serum PRL levels. The addition of TRH magnified the PRL response 2.4-fold (P=0.007). GHRP-2 increased basal serum cortisol levels (531±29nmol/l) by 35% (P=0.02); GHRH provoked no additional response, but adding TRH further increased the cortisol response by 20% (P=0.05). CONCLUSIONS The specific character of hypothalamic-pituitary function in critical illness is herewith extended to the responsiveness to GHRH and/or GHRP-2 and TRH. The observation of striking bursts of GH secretion elicited by GHRP-2 and particularly by GHRH+GHRP-2 in patients with low spontaneous GH peaks opens the possibility of therapeutic perspectives for GH secretagogues in critical care medicine.  相似文献   
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Central nervous system decompression sickness: latency of 1070 human cases   总被引:1,自引:0,他引:1  
Many aspects of central nervous system (CNS) decompression sickness (DCS) are poorly understood, including the temporal pattern of its presentation and the pathogenic mechanisms involved in the development of the disease. Using case histories and clinical series published in the literature and retrieved from treatment center records, this study is an attempt to define the interval between surfacing from a hyperbaric exposure and the onset of symptoms of CNS DCS. The results of 1070 cases of human CNS DCS were included in the study. The results show that the disease generally occurs rapidly: over 50% became symptomatic within 10 min of returning to 1 ATA, and in only 15% of cases was the onset of symptoms delayed for more than 1 h. Cerebral DCS had a more rapid onset than spinal cord disease: 50% of cerebral cases became apparent within about 3 min and a similar proportion of spinal cord cases within about 9 min from surfacing. The influence of these results on the diagnosis and treatment of dysbaric illness, on the safety of certain diving practices, and on possible pathogenic mechanisms is discussed.  相似文献   
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A 32–year–old man had an unusual gunshot wound to the leg, causing a peroneal nerve palsy. Sonography provided useful complementary findings to the electrodiagnostic localization of the injury.  相似文献   
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The purpose of this study was to determine normal, mean quadriceps angles (Q angles) for college-aged men and women, and to compare Q angles measured in the supine and the standing positions. The Q angles of 269 men and 257 women were measured in both positions by use of a specially modified goniometer. The mean Q angle for men was 12.7 degrees in the supine position and 13.6 degrees in the standing position; for women the mean Q angle was 15.8 degrees in the supine position and 17.0 degrees in the standing position. All of these differences were statistically significant. We calculated the incidence of an abnormally high Q angle, and will discuss the implications of our findings.  相似文献   
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