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Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction.  相似文献   
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To enhance individual and family health during recovery from heart surgery, this study employed nursing interventions based on self-efficacy and family stress theory during the hospitalization period and for 3 months thereafter. The effectiveness of the interventions were assessed through a randomized trial in which 67 prospective bypass and valve surgery patients, aged 30-77 years, and their spouses, were allocated either the experimental interventions or usual care and followed for 6 months. At 3 months post-surgery, the only statistically significant differences between the experimentals and controls were on perceived self-efficacy for lifting and tolerating emotional distress. At 6 months no significant differences were found on individual or family measures. Analyses revealed that age, gender and preoperative cardiac status significantly affected individual recovery. The study is continuing with a larger sample in order to explicate the recovery process and to better determine whether a low intensity nursing intervention can effect changes in individual and family recovery.  相似文献   
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Following Kemp's original studies, several others have confirmed the existence of otoacoustic emissions. Their clinical relevance remains, however, to be clarified. The various published studies have concerned small series. This study sought to specify otoacoustic emission characteristics in relation to sensorineural hearing loss (148 ears of 76 subjects). The results show that the presence of otoacoustic emissions drops as a function of hearing loss and that there is a highly statistically significant correlation between otoacoustic emission threshold and hearing loss at the 1000-Hz frequency. Otoacoustic emissions are never found when hearing loss at 1000 Hz exceeds 40 dB hearing level and when the mean audiometric hearing loss (at 500, 1000, 2000, and 4000 Hz) exceeds 45 dB hearing level. The main practical conclusion is that otoacoustic emission presence indicates middle frequency functional integrity of the outer hair cells of Corti's organ. Absence of otoacoustic emissions is harder to interpret.  相似文献   
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Background: Liver dysfunction as a result of impaired oxygen availability frequently occurs following hemorrhage and contributes to delayed mortality. Artificial oxygen carriers may improve oxygen supply to vital organs while avoiding the need for allogeneic transfusion.

Methods: Rats were subjected to hemorrhagic hypotension (mean arterial pressure = 35-40 mmHg for 120 min) and were subsequently resuscitated with (1) stored whole rat blood, (2) pentastarch, or (3) pentastarch combined with perflubron emulsion (PFE; 2.7 or 5.4 g/kg body weight), a second-generation artificial oxygen carrier. Recovery of liver adenosine triphosphate, hepatocellular injury, and expression of glutamine synthetase 1, a gene that is induced by exposure of hepatocytes to low partial pressure of oxygen, were studied at 4 h of resuscitation.

Results: Stored whole blood or pentastarch failed to restore liver adenosine triphosphate concentrations after prolonged shock as compared to sham controls and resulted in increased gene expression of glutamine synthetase 1. Addition of 2.7 g PFE/kg restored liver adenosine triphosphate to control, whereas 5.4 g PFE/kg resulted in adenosine triphosphate concentrations significantly above control. Improved hepatocellular oxygen supply was also confirmed by restoration of the physiologic expression pattern of glutamine synthetase 1. Serum enzyme concentrations were highest after resuscitation with stored blood, whereas addition of PFE failed to further decrease enzyme concentrations as compared to pentastarch alone.  相似文献   

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The September 2002 COM. A 24-year-old female presented with a history of 3 generalized seizures, the first of which had occurred 6 months before admission. Her neurological examination was normal, but upon admission her MRI showed a small cystic lesion in the left parieto-occipital region. The lesion was hyper-intense on T-2 weighted images and did not show contrast enhancment. At surgery, the tumor was found to be deep to the cortex and was a cyst with amber fluid surrounded by gliotic brain. Microscopically, the tumor was well-demarcated from the surrounding tissues, which showed reactive changes, including Rosenthal fibers. The tumor was composed of GFAP-positive glial cells, which were arranged in a pseudopapillary fashion around blood vessels. In between, the tumor cells were positive for neuronal markers. The diagnosis was papillary glioneuronal tumor (PGNT), a relatively recently described lesion that may be a variant of ganglioglioma. The current literature on PGNTs is reviewed.  相似文献   
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Microdeletion syndromes are commonly transmitted as dominant traits and are frequently associated with variably expressed pleiotropic phenotypes. Nonlethal homozygous microdeletions, on the other hand, are very rare. Here, we delineate the fifth and so far largest homozygous microdeletion in nonmalignancies of approximately 400 kb on chromosome 4q11-q12 in a large consanguineous East-Anatolian family with six affected patients. The deleted region contains the beta-sarcoglycan gene (SGCB), the predicted gene SPATA18 (spermatogenesis associated 18 homolog) and several expressed sequence tags. Patients presented with a severe and progressive Duchenne-like muscular dystrophy phenotype, a combination of hyperlaxity and joint contractures, chest pain, palpitations, and dyspnea.  相似文献   
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Summary Lipoprotein(a), as an atherogenic particle, represents an independent risk factor for coronary heart disease. In the present study the morphological distribution of apoprotein (a) and apoprotein B within the arterial wall is described. Apoprotein B, a constituent of very low-density lipoprotein, low-density lipoprotein and lipoprotein(a) has previously been demonstrated in atheromatous lesions. Lipoprotein(a) possesses an additional protein, designated apoprotein (a). Autopsy material (n=74) from the left coronary artery and from the thoracic aorta has been examined by means of immunohistochemistry and both apoprotein (a) and apoprotein B were detected, primarily associated with the extracellular matrix and accumulating in lesions in the arterial wall. The staining pattern for both antigens was almost always found to be congruent, suggesting that the detection of (a)-antigen has to be attributed at least in part to the presence of lipoprotein(a). It is concluded that both low-density lipoprotein and lipoprotein(a) have an important role in the pathogenesis of atherosclerosis.  相似文献   
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