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101.
OBJECTIVE: The authors used functional magnetic resonance imaging (fMRI) to investigate brain activation in patients with schizophrenia and major depression while they performed two tasks-a vigilance task and a mental arithmetic task-that differed in cognitive complexity. METHOD: In the vigilance task, the participants had to press a response button whenever a specific number was seen on a screen inside the MR scanner. In the mental arithmetic task, the participants had to add two consecutive numbers and press the response button whenever the sum was 10. fMRI was performed with a 1.5-T MR scanner. Twelve patients with recurrent nonpsychotic unipolar major depression, 12 patients with schizophrenia, and 12 healthy comparison subjects were included in the study. RESULTS: Performance data showed that the patients were impaired relative to the comparison subjects and showed no difference in performance between the patient groups. The patients with schizophrenia, but not those with major depression, had less activation in prefrontal brain regions, relative to the comparison participants. However, subtracting brain activation during the vigilance task from activation during the mental arithmetic task showed that the schizophrenia patients had activation in parietal areas. CONCLUSIONS: A double dissociation of parietal and frontal lobe activation was found for the schizophrenia patients and the depression patients. The greater parietal lobe activation in the patients with schizophrenia may reflect a compensatory strategy for the failure to recruit cognitive processes that involve frontal lobe areas when solving a mental arithmetic task.  相似文献   
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BACKGROUND: Avoiding damage to blood vessels is often the concern of the neurosurgeon during tumor surgery. Using angiographic image data in neuronavigation may be useful in cases where vascular anatomy is of special interest. Since 2003, we have routinely used 3D ultrasound angiography in tumor surgery, and between January 2003 and May 2005, 62 patients with different tumors have been operated using intraoperative 3D ultrasound angiography in neuronavigation. METHODS: An ultrasound-based neuronavigation system was used. In addition to 3D ultrasound tissue image data, 3D ultrasound angiography (power Doppler) image data were acquired at different stages of the operation. The value and role of navigated 3D ultrasound angiography as judged by the surgeon were recorded. RESULTS: We found that intraoperative ultrasound angiography was easy to acquire and interpret, and that image quality was sufficient for neuronavigation. In 26 of 62 cases, ultrasound angiography was found to be helpful by visualizing hidden vessels adjacent to and inside the tumor, facilitating tailored approaches and safe biopsy sampling. CONCLUSIONS: Intraoperative 3D ultrasound angiography is straightforward to use, image quality is sufficient for image guidance, and it adds valuable information about hidden vessels, increasing safety and facilitating tailored approaches. Furthermore, with updated 3D ultrasound angiography imaging, accuracy of neuronavigation may be maintained in cases of brain shift.  相似文献   
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BACKGROUND: The deleterious effects of perioperative malnutrition on recovery after general surgery are established. Since the effects of perioperative malnutrition on recovery after vascular surgery are not known, we examined the effects of nutritional status, and risk factors predictive of malnutrition, on outcome after vascular surgery. METHODS: The records of all open index vascular cases (abdominal aortic aneurysm [AAA] repair, carotid endarterectomy [CEA], lower extremity bypass) performed at the Veterans Affairs (VA) Connecticut between July 2004 and June 2005 were reviewed. The primary outcome was mortality; secondary outcomes included infection and nutritional risk index (NRI) scores. RESULTS: Sixty-eight open vascular cases were performed during the study period. Nutritional depletion developed in 55% of patients and was more likely in patients undergoing AAA (85%) or bypass (77%) than CEA (30%; P = .0005). Patients who developed malnutrition had similar mortality as patients who did not develop postoperative malnutrition (6.1% vs. 3.7%; P = .68); however, malnourished patients had higher rates of postoperative infection (24.2% vs. 3.7%; P = .03). Chronic renal failure was the only patient-associated risk factor predictive of postoperative nutritional depletion (odds ratio 5.9, confidence interval 1.0 to 33.6; P = .04). CONCLUSIONS: Patients undergoing major open vascular surgery have high rates of postoperative malnutrition, with patients undergoing AAA repair having the highest rates of postoperative malnutrition and infection. Patients with chronic renal failure undergoing vascular surgery are associated with increased risk for postoperative malnutrition and may be a group to target for perioperative risk factor modification and nutritional supplementation.  相似文献   
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Since the beginning of the 1990s the public health situation in Russia has been characterized by an extremely high mortality and a significant reduction in life expectancy. Cardiovascular diseases remained the major cause of death. Only a few large population studies were conducted in Russia during this period. A total of 1968 men and 1737 women aged 18–75 years participated in a health survey in Arkhangelsk, Russia, over the period 1999–2000. Investigation included assessment of classic cardiovascular risk factors (family history, smoking, blood pressure, and blood lipids) along with general health variables. The paper presents sex specific data on risk factors for coronary heart disease. Though the cardiovascular mortality is high in Russia, the calculated risk for coronary heart disease (the Framingham risk score and the Norwegian risk score) was lower in all age groups of men and women in Arkhangelsk compared with studies from the Western Europe and USA. Our data suggest that high cardiovascular mortality in Russia may be driven not only by the classic risk factors for coronary heart disease.  相似文献   
105.
We investigated the effects of conflicting cues in visual attention on brain function, based on a modified version of the Posner cue-target paradigm. The classic paradigm utilizes either a peripheral or centrally placed cue that involuntary or voluntary results in a shift of attention to the cued side. The modified paradigm involves presenting both a peripheral and central cue at the same time, but where the two cues convey conflicting information regarding direction of attention. Functional magnetic resonance imaging (fMRI) were used to record neuronal activation in localized brain areas and networks when the subjects performed the attention task. We hypothesized that the 'exogenous invalid/endogenous valid' condition would activate the anterior attention system to a larger extent than the 'exogenous valid/endogenous invalid' condition, reflecting a need for top-down information processing in this condition. The results for performance data showed that the peripheral cue took precedence over the centrally placed cue when the two cues were in conflict, since reaction times were significantly longer in the "exogenous invalid/endogenous valid" condition. The fMRI data showed an increase in activation in the visual cortex, the left parietal lobule, and in the left cingulate gyrus in both the exogenous valid/endogenous invalid and exogenous invalid/endogenous valid conditions. For the exogenous invalid/endogenous valid condition, there were, in addition, significant activations also in the inferior and middle frontal gyri, and in the precentral gyrus. We interpret these findings as reflecting that these brain areas particularly involved in top-down modulation of attention that interferes with a bottom-up, exogenous-driven effect.  相似文献   
106.
Background: Previous studies from Nordic countries suggest that parent ratings of children's emotional and behavioural problems using the Child Behavior Checklist (CBCL) are among the lowest in the world. However, there has been no Norwegian population study with acceptable response rates to provide valid Norwegian reference data. Aims: Firstly, to compare CBCL Internalizing, Externalizing, Total Problems and Competence scores of Norwegian children and adolescents with those from 1) previous Norwegian studies, 2) other Nordic countries, and 3) international data. Secondly, to present Norwegian reference data in order to perform these comparisons. Thirdly, to investigate the effects of age, gender, socio-economic and urban/rural status on the CBCL. Methods: A stratified cluster sample of 2582 school children (1302 girls and 1280 boys) was identified from the general Norwegian population and their parents were asked to complete the CBCL. Results: The response rate was 65.5%. The mean Total Problems score for the whole sample was 14.2 (standard deviation, s = 14.1). Girls were rated as having greater Competence and fewer Total Problems than boys. Younger children had more Total Problems than adolescents. Parents with low education reported more child Total Problems and lower Competence than those with high education. All effect sizes were small, except for the effect of parental education on child Competence, which was moderate. Conclusions: Total Problems scores were lower than in other societies. The data from this study obtained from one county in central Norway provide an important reference for clinical practice and treatment outcome research.  相似文献   
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Ipilimumab was the first treatment that improved survival in advanced melanoma. Efficacy and toxicity in a real-world setting may differ from clinical trials, due to more liberal eligibility criteria and less intensive monitoring. Moreover, high costs and lack of biomarkers have raised cost-benefit concerns about ipilimumab in national healthcare systems and limited its use. Here, we report the prospective, interventional study, Ipi4 (NCT02068196), which aimed to investigate the toxicity and efficacy of ipilimumab in a real-world population with advanced melanoma. This national, multicentre, phase IV trial included 151 patients. Patients received ipilimumab 3 mg/kg intravenously and were followed for at least 5 years or until death. Treatment interruption or cessation occurred in 38%, most frequently due to disease progression (19%). Treatment-associated grade 3 to 4 toxicity was observed in 28% of patients, and immune-related toxicity in 56%. The overall response rate was 9%. Median overall survival was 12.1 months (95% CI: 8.3-15.9); and progression-free survival 2.7 months (95% CI: 2.6-2.8). After 5 years, 20% of patients were alive. In a landmark analysis from 6 months, improved survival was associated with objective response (HR 0.16, P = .001) and stable disease (HR 0.49, P = .005) compared to progressive disease. Poor performance status, elevated lactate dehydrogenase and C-reactive protein were identified as biomarkers. This prospective trial represents the longest reported follow-up of a real-world melanoma population treated with ipilimumab. Results indicate safety and efficacy comparable to phase III trials and suggest that the use of ipilimumab can be based on current cost-benefit estimates.  相似文献   
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