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11.
Penetrating cardiac trauma is a life-threatening condition and presents a therapeutic challenge for the surgeon. Additional multiple organ-system injuries, as are common in the setting of war, further complicate the management of such patients. We present the case of a 9-year-old girl who sustained multiple injuries from an unexploded artillery shell, resulting in a retained intracardiac shrapnel. Her cardiac pathology consisted of a shrapnel located in the interventricular septum accompanied by a pneumopericardium and a right-sided hemopneumothorax. The presentation and management of this patient are the subjects of this report.  相似文献   
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We studied distraction osteogenesis in canine experimental model using two types of external fixators, Ilizarov (n=6) or AO unilateral (n=9) external fixator. Distraction started 1 week after surgery (2 x 0.5 mm/day) and lasted for 3 weeks. Specimens were harvested from weeks 7 through 12. The outcome was assessed by X-ray, histology, histomorphometry and microradiography. Bone regeneration as observed by X-rays was satisfactory and similar in both groups. Both endochondral ossification and intramembranous ossification were found simultaneously in both groups. In both groups, bone formation parameters were significantly higher in the area of consolidating bone. No differences in histomorphometric parameters existed between the groups. In the study period, the bone formation was enhanced and prevailed in the distraction area. This study demonstrated the utility of the canine experimental model for the study of distraction osteogenesis.  相似文献   
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The objective of this study was to assess whether reduced glucose metabolism (rCMRGlu) and cognitive functioning could predict development of Alzheimer's disease (AD) in subjects with mild cognitive impairment (MCI). Twenty MCI patients underwent baseline and follow-up investigations of rCMRGlu, as measured by PET, and cognitive function measured by neuropsychological test assessments. Subjects were clinically followed up with an average interval of 36.5 months. Two groups were obtained after the second clinical assessment. Nine patients were diagnosed as AD and classified as progressive MCI (P-MCI), whereas 11 patients remained clinically stable and were classified as stable MCI (S-MCI). There were no differences in demographic variables or baseline MMSE between the two subgroups. Logistic regression indicated the two variables that most effectively predicted future development of AD were rCMRGlu from the left temporoparietal area and performance on the block design. These combined measures gave an optimal 90% correct classification rate, whereas only rCMRGlu or neuropsychology alone gave 75% and 65% correct classification, respectively. Measures of temporoparietal cerebral metabolism and visuospatial function may aid in predicting the evolution to AD for patients with MCI.  相似文献   
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A proportion of Alzheimer's disease (AD) patients treated for several months with cholinesterase (ChE) inhibitors have shown some favorable response on cognition, but the characteristics of the responders are still unclear. This study attempts to identify the characteristics of individuals with a positive behavioral response after a double-blind randomized administration of a single oral dose of tacrine (40 mg) and placebo to AD patients. Furthermore, the relationship between single-dose and long-term responders are examined. Twenty-four mildly to very mildly demented AD patients participated in the study. They all fulfilled the diagnosis of probable AD according to NINCDS-ADRDA criteria. Active treatment (tacrine 40 mg) and placebo was administered in random order on 2 consecutive days, and the effects were evaluated within 2 h using neuropsychological tests (assessing visuospatial ability, episodic memory and attention), registration of EEG activity and measurement of red blood cells (RBC) acetylcholinesterase (AChE), ChE activity and concentrations of tacrine and its metabolites in plasma. Results demonstrated significant improvement, tacrine compared to placebo, in measures of attention, but not in episodic memory or visuospatial ability. A single-dose response was therefore defined in terms of improvement in attention. The tacrine plasma concentration (pcTHA) showed a positively skewed distribution (mean +/- SD: 10.5 +/- 11.8, range: 1.0-51.8 ng/ml). There were no significant differences between single-dose responders compared to nonresponders in pcTHA, metabolites of tacrine, inhibition of AChE in RBC, tau levels in CSF, AChE activity in CSF or plasma and demographic variables. However, single-dose responders showed a higher right frontal alpha/theta ratio on EEG and had lower glucose metabolism in the parietal-temporal association cortex at baseline. In addition, the frequency of apolipoprotein E (APOE) epsilon 4 alleles was higher in responders. Interestingly, the single-dose response was related to the long-term response, although not significantly, which probably was due to lack of power. To conclude, the present study identified single-dose responders in terms of improved attentional performance associated with a relatively higher alpha/theta activity in the right frontal regions of the brain measured on EEG and predominance of APOE epsilon 4 allele.  相似文献   
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Medical Oncology - First-line treatments of metastatic melanoma are usually decarbazine (DTIC) and/or α-interferon based, with response rates in the range of at most 20–30%. In this...  相似文献   
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OBJECTIVES: We determined the frequencies of apolipoprotein E (apo E) alleles and examined the effect of apo E polymorphism on lipoprotein particle sizes in Serbian healthy, middle-aged individuals. DESIGN AND METHODS: We performed apo E phenotype by immunobloting method in 183 men and 143 women (mean years: 56.3+/-10.60 and 54.9+/-10.31, respectively). Plasma lipid and apolipoprotein levels were measured by routine laboratory methods. LDL and HDL particle sizes were determined by nondenaturing polyacrylamide gradient (3-31%) gel electrophoresis. RESULTS: The apo E allele frequencies were epsilon2--4.9%, epsilon3--86.5%, and epsilon4--8.6%. Men with epsilon4 allele had lower HDL-C and Apo AI concentrations than epsilon3 men. The epsilon2 allele men had the smallest LDL particles, highest percent of subjects with LDL phenotype B and highest TG/HDL-C ratio. Women with epsilon2 allele had lowest concentration of apo B. The epsilon4 allele women had smallest HDL particles and highest percent of the subjects with small-sized HDL phenotype. CONCLUSIONS: This study showed gender-related effect of apo E polymorphism on lipoprotein particle size. In men, possession of the epsilon2 allele is associated with small LDL particles, whereas in women, epsilon4 allele is associated with small HDL particles. Differences in gender-related influence of apo E polymorphism on LDL and HDL particle sizes could be clinically useful in strategy for reduction of coronary disease risk in middle-aged men and women.  相似文献   
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Maintenance of airway secretion clearance, or airway hygiene, is important for the preservation of airway patency and the prevention of respiratory tract infection. Impaired airway clearance often prompts admission to the intensive care unit (ICU) and can be a cause and/or contributor to acute respiratory failure. Physical methods to augment airway clearance are often used in the ICU but few are substantiated by clinical data. This review focuses on the impact of oral hygiene, tracheal suctioning, bronchoscopy, mucus-controlling agents, and kinetic therapy on the incidence of hospital-acquired respiratory infections, length of stay in the hospital and the ICU, and mortality in critically ill patients. Available data are distilled into recommendations for the maintenance of airway hygiene in ICU patients.  相似文献   
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