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61.
Distractibility, which can be defined as an attention deficit in which orientation toward irrelevant targets can be hardly inhibited, is commonly related to a dysfunction of the dorsolateral prefrontal cortex. Here, we show that increased distractibility, observed in a patient with an exceptionally small lesion located in the upper brainstem, may result from the interruption of a direct tract that connects the prefrontal cortex to the superior colliculus, a structure involved in both eye movement control and attentional shifts.  相似文献   
62.
Combined treatment of metastatic osteosarcoma of the spine   总被引:1,自引:0,他引:1  
We report on a 28-year-old male with a single metastasis of an osteosarcoma in the twelfth thoracic vertebra occurring 9 years after initial diagnosis of the primary tumour in the left distal femur and neoadjuvant treatment according to a modified T-10 protocol. After pre-operative second-line combination chemotherapy with doxorubicin, carboplatin and etoposide leading to regression of the primarily inoperable metastasis wide resection of the tumour employing total spondylectomy was done. The duration of response had been 65 months since the end of subsequent postoperative chemotherapy with the same regimen. Copyright Copyright 1999 S. Karger AG, Basel  相似文献   
63.
The "at birth" system which is used in Sheffield to identify children likely to die unexpectedly in infancy, was tested retrospectively in Birmingham (83 cases) and in Newcastle upon Tyne (56 cases). The discrimination between cases and age-matched controls was poor in both cities. Analysis of the 8 factors used in the system showed that only 2 maintained significant case/control differences in Birmingham and Newcastle. Further investigation showed that other factors from maternity records showed significant case/control differences in these cities. Although the system used in Sheffield would not be of use in a prospective prevention programme in either Newcastle or Birmingham, the possibility of evolving an "at risk" system which might apply more widely is discussed.  相似文献   
64.
Processing of tactile stimuli within somatosensory cortices has been shown to be complex and hierarchically organized. However, the precise organization of nociceptive processing within these cortices has remained largely unknown. We used whole-head magnetoencephalography to directly compare cortical responses to stimulation of tactile and nociceptive afferents of the dorsum of the hand in humans. Within the primary somatosensory cortex (SI), nociceptive stimuli activated a single source whereas tactile stimuli activated two sequentially peaking sources. Along the postcentral gyrus, the nociceptive SI source was located 10 mm more medially than the early tactile SI response arising from cytoarchitectonical area 3b and corresponded spatially to the later tactile SI response. Considering a mediolateral location difference between the hand representations of cytoarchitectonical areas 3b and 1, the present results suggest generation of the single nociceptive response in area 1, whereas tactile stimuli activate sequentially peaking sources in areas 3b and 1. Thus nociceptive processing apparently does not share the complex and hierarchical organization of tactile processing subserving elaborated sensory capacities. This difference in the organization of both modalities may reflect that pain perception rather requires reactions to and avoidance of harmful stimuli than sophisticated sensory capacities.  相似文献   
65.
Head injury in child abuse: evaluation with MR imaging   总被引:3,自引:0,他引:3  
To evaluate the usefulness of magnetic resonance (MR) imaging in the diagnosis of head injury in child abuse, the authors compared the findings at head MR imaging and computed tomography (CT) in 19 abused children. Subdural hematomas (15 cases), cortical contusions (six cases), and shearing injuries (five cases) were demonstrated to particular advantage with MR imaging. CT remained superior in the detection of subarachnoid hemorrhage. MR imaging appears to be valuable in the assessment of patients with suspected intracranial injury due to child abuse.  相似文献   
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The Model for End-Stage Liver Disease (MELD) is widely used to predict the short-term mortality in patients with cirrhosis, but potential limitations of this score have been reported. The aim of this study was to improve the score's prognostic accuracy by assessing new objective variables. Data of 310 consecutive patients with cirrhosis who underwent elective transjugular intrahepatic portosystemic shunt placement between July 1995 and March 2005 were analyzed retrospectively. Bivariate and multivariate analyses were performed by proportional hazard Cox regression models. The area under the receiver operating characteristic curve (auROC) and the likelihood ratio test were used to evaluate the performance of the models for predicting early mortality. Findings were validated in a cohort of 451 consecutive patients with cirrhosis on waiting list for liver transplantation. Bivariate analyses showed that the following variables correlated with time to death: age, serum bilirubin, serum creatinine, international normalized ratio of prothrombin time, serum albumin, serum sodium, and MELD. Multivariate analysis revealed that MELD, serum sodium, and age were independently associated with the risk of death. The integrated MELD model (iMELD, incorporating serum sodium and age) was better than original MELD in predicting 12-month mortality: auROC increased by 13.4% and the likelihood ratio statistic from 23.5 to 48.2. The improved accuracy of iMELD was confirmed in the validation sample of 451 patients with cirrhosis on the waiting list for liver transplantation by increasing auROC (+8%) and likelihood ratio statistic (from 41.4 to 82.0). This study shows that in patients with cirrhosis, serum sodium and age are predictors of mortality independent of the MELD score. The incorporation of these variables into the original MELD formula improves the predictive accuracy of time to death.  相似文献   
69.

Background

Adequate vitamin D concentrations during pregnancy are necessary to neonatal calcium homeostasis, bone maturation and mineralization. The aim of study is to evaluate serum vitamin D concentrations in mothers and their newborns and effect of vitamin D deficiency on pregnancy outcomes.

Methods

552 pregnant women were recruited from Tehran University educating hospitals in the winter of 2002. Maternal and cord blood samples were taken at delivery. The serum was assayed for 25-hydroxyvitamin D3, calcium, phosphorus and parathyroid hormone.

Results

The prevalence of vitamin D deficiency in maternal and cord blood samples were 66.8% and 93.3%, respectively (<35 nmol/l). There was significant correlation between maternal and cord blood serum concentrations of vitamin D. In mothers with vitamin D deficiency, cord blood vitamin D concentrations was lower than those from normal mothers (P = .001). Also, a significant direct correlation was seen between maternal vitamin D intake and weight gain during pregnancy.

Conclusion

Consideration to adequate calcium and vitamin D intake during pregnancy is essential. Furthermore, we think it is necessary to reconsider the recommendation for vitamin D supplementation for women during pregnancy.  相似文献   
70.
Cadmium is a highly toxic, carcinogenic, and atherogenic element. A central principle in many Cd-induced pathophysiologies is the induction of cell death. In past studies Cd was shown to cause apoptosis, necrosis, programmed necrosis, or autophagy. This study was conducted to precisely define the end stage processes and outcome of Cd-induced cell death in endothelial cells (ECs). We show that Cd leads to acidification and permeabilization of lysosomes, followed by the release of active DNAse II from lysosomes. The absence of nuclear DNA due to DNAse II activity may have lead to misinterpretations of the type of cell death outcome in previous studies. Further, Cd-induced cell death is characterized by a massive release of lactate dehydrogenase (LDH), a gold standard marker for the occurrence of plasma membrane rupture i.e. necrosis. Importantly, lentivirus-based over-expression of the anti-apoptotic protein BCL-XL abrogates lysosomal rupture, DNA degradation and LDH release, clearly indicating that Cd induces a programmed form of cell death with a necrotic endpoint.  相似文献   
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