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1.
Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment.  相似文献   
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Classification of injuries to the thoracolumbar spine   总被引:1,自引:0,他引:1  
Significant advances have been made over the past 40 years in the understanding of the pathoanatomy, biomechanics, and neurophysiology of thoracolumbar injuries. These improvements are reflected in the sophisticated classifications currently in use. Yet, we remain in a transitional phase of our classification of these fractures. Future schemes will probably offer two precise classifications--one neurologic and one structural--for every injury.  相似文献   
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The receptor tyrosine kinase (RTK) Ret is activated by the formation of a complex consisting of ligands such as glial cell line-derived neurotrophic factor (GDNF) and glycerophosphatidylinositol-anchored coreceptors termed GFRalphas. During activation, Ret translocates into lipid rafts, which is critical for functional responses to GDNF. We found that Ret was rapidly ubiquitinated and degraded in sympathetic neurons when activated with GDNF, but, unlike other RTKs that are trafficked to lysosomes for degradation, Ret was degraded predominantly by the proteasome. After GDNF stimulation, the majority of ubiquitinated Ret was located outside of lipid rafts and Ret was lost predominantly from nonraft membrane domains. Consistent with the predominance of Ret degradation outside of rafts, disruption of lipid rafts in neurons did not alter either the GDNF-dependent ubiquitination or degradation of Ret. GDNF-mediated survival of sympathetic neurons was inhibited by lipid raft depletion, and this inhibitory effect of raft disruption on GDNF-mediated survival was reversed if Ret degradation was blocked via proteasome inhibition. Therefore, lipid rafts sequester Ret away from the degradation machinery located in nonraft membrane domains, such as Cbl family E3 ligases, thereby sustaining Ret signaling.  相似文献   
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Background Cosmetic changes are to be expected after radiotherapy for skin tumours. Objectives This study aimed to answer the questions: How frequent are cosmetic changes after soft X‐ray therapy? Do treatment parameters, tumour thickness, localization and size of the irradiated field have a major influence? Were patients irritated by the visual appearance of the irradiated field? Methods In total, 2474 examinations of 1149 irradiated fields were performed. Results Hypopigmentation was found in 64.7% of examinations more than 90 days after therapy, teleangiectases in 43.1%, erythema in 24.8%, and hyperpigmentation in 16.8%. The frequency of hypopigmentation, teleangiectases and hyperpigmentation increased with time from X‐ray exposure; more than 4 years after therapy hypopigmentation was diagnosed in 91.8% and teleangiectases in 82.2% of examinations. Total dose, the time–dose–fractionation factor (TDF), field size and dose per fraction were significantly related to the frequency of cosmetic changes. Incidence rates of cosmetic changes differed by less than 15% if different treatment conditions were compared: thicker vs. thinner tumours, larger vs. smaller fields, higher vs. lower total doses, doses per fraction, and TDF. Frequencies of hypopigmentation, teleangiectases, erythema and hyperpigmentation differed by more than 15% between some localizations on the head. Women reported irritation by the visual appearance of the irradiated field in 12.6% of 1116 interviews, and men in 4.4% of 1284 interviews. Conclusions Cosmetic changes after soft X‐ray therapy are relatively frequent. Treatment parameters, tumour thickness and field size have only a minor influence. Few patients, but more women than men, were irritated by the visual appearance of the irradiated field.  相似文献   
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BACKGROUND: Epidemiologic studies reveal that posttraumatic stress disorder (PTSD) is highly comorbid with both conduct disorder and major depression in men. The genetic and environmental etiology of this comorbidity has not been examined. METHODS: Data were analyzed from 6744 middle-aged male-male monozygotic and dizygotic twins from the Vietnam Era Twin Registry. Conduct disorder, major depression, and PTSD were assessed via telephone interview using the Diagnostic Interview Schedule for the DSM-III-R in 1992. Structural equation modeling was used to estimate additive genetic, shared environmental, and individual-specific environmental effects common and specific to conduct disorder, major depression, and PTSD. RESULTS: The association between conduct disorder and PTSD was explained primarily by common shared environmental influences; these explained 10% (95% confidence interval: 6%-17%) of the variance in PTSD. The association between major depression and PTSD was largely explained by common genetic influences; these explained 19% (95% confidence interval: 11%-26%) of the variance in PTSD. CONCLUSIONS: Our findings suggest that different etiologic mechanisms explain the association of conduct disorder and major depression with PTSD in male veterans. If replicated in other populations, results suggest research aimed at identifying specific genetic and environmental factors that influence PTSD may benefit from starting with those that have been more consistently and strongly associated with major depression and conduct disorder.  相似文献   
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SUMMARY Serum potassium was measured within 24 hours in 156 patients (48 male, 108 female) with an average age of 81.9 years admitted to the unit with acute illness. Of the 156 patients, 88 (56.4%) were taking diuretics (none was on ACE inhibitors); 20 patients (12.8%) were also on digoxin therapy. In all, 24 patients (16%) had hypokalaemia and 3 (2%) hyperkalaemia. Hypokalaemia was seen in patients associated with acute illness. There was no significant difference between the diuretic and non-diuretic groups. Monitoring of serum potassium is not routinely indicated to detect hypokalaemia in patients on diuretic therapy except in those with severe hepatic or renal impairment or those on digoxin.  相似文献   
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The indications for surgical fusion, as opposed to halo fixation, in the management of cervical spine injury are still unclear. At St. Louis University Medical Center a conservative protocol has been adopted to treat almost all cervical spine fractures with halo fixation. To determine what factors have contributed to failure of halo fixation, the records and radiographs of all patients with cervical spine injuries who were treated at that institution between 1984 and 1986 were reviewed. During this interval, 124 patients were treated, consisting of 93 men and 31 women between 6 and 94 years old. Of these, 15 (12%) had cervical fusion without preoperative halo device application. This group included eight patients with old injuries and delayed diagnosis, three with nonreducible locked facets, and four with miscellaneous indications. The remaining 109 patients were treated with halo vests. Four died before completing the 3-month standard treatment. Of those completing the treatment, 48 had C1-2 level injuries and 57 had C3-T1 level injuries. Sixteen patients (15%) failed their halo treatments and required surgical fusion: eight while still in halo fixation and eight after they had completed treatment with a halo device. Failure of halo treatment was indicated by recurrent dislocation in 13 patients and increased neurological deficit in three. Thirteen of the patients who failed treatment had C3-T1 injuries and three had C1-2 injuries. Of 27 patients with odontoid fractures, only two (7.4%) failed halo fixation. There were no failures in 11 patients with hangman's fractures. Of the 57 patients with C3-T1 injuries, 13 (23%) failed treatment, nine of whom had locked or "perched" facets. The factors causing failure of halo fixation were analyzed. The overall success rate was 85%, suggesting that the halo vest can be used to treat most patients with cervical spine injuries. Under certain circumstances (in the presence of old injuries, difficult reduction, or locked or "perched" facets), surgery may be indicated to avoid unnecessary delay in definitive management.  相似文献   
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BACKGROUND: Genetic influences have been shown to play a major role in determining the risk of attention-deficit hyperactivity disorder (ADHD). In addition, prenatal exposure to nicotine and/or alcohol has also been suggested to increase risk of the disorder. Little attention, however, has been directed to investigating the roles of genetic transmission and prenatal exposure simultaneously. METHOD: Diagnostic telephone interview data from parents of Missouri adolescent female twin pairs born during 1975-1985 were analyzed. Logistic regression models were fitted to interview data from a total of 1936 twin pairs (1091 MZ and 845 DZ pairs) to determine the relative contributions of parental smoking and drinking behavior (both during and outside of pregnancy) as risk factors for DSM-IV ADHD. Structural equation models were fitted to determine the extent of residual genetic and environmental influences on ADHD risk while controlling for effects of prenatal and parental predictors on risk. RESULTS: ADHD was more likely to be diagnosed in girls whose mothers or fathers were alcohol dependent, whose mothers reported heavy alcohol use during pregnancy, and in those with low birth weight. Controlling for other risk factors, risk was not significantly increased in those whose mothers smoked during pregnancy. After allowing for effects of prenatal and childhood predictors, 86% of the residual variance in ADHD risk was attributable to genetic effects and 14% to non-shared environmental influences. CONCLUSIONS: Prenatal and parental risk factors may not be important mediators of influences on risk with much of the association between these variables and ADHD appearing to be indirect.  相似文献   
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