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51.
Peripheral blood neutrophils (PMN) from patients with paracoccidioidomycosis killed and digested Paracoccidioides brasiliensis much less than did PMN from normal individuals or from patients with other diseases. However, deficiency in killing ability was less specific than digestive deficiency and correlated poorly with it. We conclude that the capacities of PMN to digest and kill P. brasiliensis are not intimately related phenomena, and that in paracoccidioidomycosis the key deficiency of neutrophil function is that of digestion of P. brasiliensis.  相似文献   
52.
Minor experience still exists in our country with regard to the use of valve homografts in cardiac surgery. Only a few implantations have been performed in cases of right ventricular outflow tract reconstruction in addition to our own experience in cases of infective endocarditis of the aortic valve. We present a case of aortic valve replacement by using an antibiotic-sterilized fresh pulmonary valve autograft. The case is described and the possible advantages of the use of pulmonary allografts in the aortic position are discussed.  相似文献   
53.
A commercial double-test tablet (Rosco PGUA/indole) for detection of beta-glucuronidase (beta-GUR) activity and indole production was evaluated on a collection of 393 isolates of Enterobacteria. Both beta-GUR and indole were positive on 96.6% of Escherichia coli strains. beta-GUR, only, was also detected in 25 Shigella spp., four Enterobacter cloacae, eight Citrobacter freundii, and five Salmonella enteritidis strains, none of which were indole producers. An additional 261 consecutive clinical isolates of oxidase-negative nonswarming Gram-negative bacilli were studied in a parallel comparative field trial against conventional identification methods. For 200 strains, the standard method and PGUA/indole test were performed from the primary culture plate. The remaining 61 (23.4%) required subculture before testing. Sensitivity, specificity, positive predictive value, and negative predictive value of PGUA/indole test in the screening for E. coli were, respectively, 94.1%, 100%, 100%, and 87.1%. In our experience, PGUA/indole test is a rapid, precise, simple-to-perform, and economical method for screening E. coli. However, the need for a large inoculum may limit its application on primary cultures.  相似文献   
54.
A case-control study was designed to identify associations between polymorphisms at p53, cytochrome P-450 (CYP1A1) and glutathione-S-transferases and endometrial cancer susceptibility. Among all polymorphisms analysed, an insertional variant in p53 (P53PIN3) and two polymorphisms in the 3''-end and exon 7 of CYP1A1 showed significant association with enhanced endometrial cancer risk.  相似文献   
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56.
The binding of racemic warfarin, its enantiomers, and several nonsteroidal anti-inflammatory agents to human serum albumin was investigated by equilibrium dialysis at 4 degrees C in pH 7.4 phosphate buffer. The primary binding constant for the S(-) enantiomer of warfarin was approximately two times greater than the corresponding binding of the R(+) enantiomer. The effect of azapropazone, phenylbutazone, naproxen, ibuprofen, mefenamic acid, and tolmetin on the binding of racemic warfarin and its enantiomers was studied. Warfarin was displaced by all of the nonsteroidal anti-inflammatory agents except tolmetin. Azapropazone caused the largest displacement of warfarin (39 to 46% free warfarin versus 2.5 to 6% free warfarin without competing drug), followed by phenylbutazone (23 to 43% free warfarin), naproxen (9 to 24% free warfarin), mefenamic acid (5 to 11.5% free warfarin), and ibuprofen (5 to 9% free warfarin). Azapropazone and phenylbutazone competed with warfarin for the same primary binding site on the albumin molecule. Naproxen appeared to affect warfarin binding at both primary and secondary sites. Ibuprofen and mefenamic acid interfered with the binding of warfarin at its secondary sites. In contrast to the other drugs studied, tolmetin caused an increase in the primary binding constant of warfarin. Structural analysis indicated that a common feature of those compounds which primarily bind at the warfarin site is a hydrophobic area bearing a widely delocalized negative charge.  相似文献   
57.
The purpose of this study was to analyze the clinical aspects in 130 patients presenting periodic lateralized epileptiform discharges (PLEDs) in their EEG and to compare these results with those found in the literature. Etiology, neurologic deficit, seizure occurrence, and evolution were studied in each patient by historical review. The recordings were obtained on 8- or 16-channel EEGs with electrode placement according to the International 10-20 System. Recordings containing PLEDs were selected. PLEDs were defined as repetitive periodic, focal, or hemispheric epileptiform discharges (spikes, spike and waves, polyspikes, sharp waves) usually recurring every 1 to 2 seconds. The statistical study was carried out via the chi(2) test using the computer program SPSS. The main etiology found in this group of patients was stroke (61 of 130 patients). Other processes found were brain infections, tumors, hematomas, and several other entities grouped together as miscellaneous (anoxic encephalopathy, subarachnoid hemorrhage, craniocerebral trauma, Creutzfeldt-Jacob disease, migraine, multiple sclerosis, and aminophylline intoxication). Half of these patients (65 of 130) developed seizures, mostly partial motor seizures. No significant relation between etiology and seizures was found (chi(2) = 2.81, P = 0.4222). Seizures recurred in 14 of 130 patients during a follow-up of 14.5 months. PLEDs were not recorded in any EEG at the time of seizure recurrence. PLEDs constitute a distinctive but uncommon EEG phenomenon of repetitive, periodic, and stereotyped lateralized complexes. In agreement with the literature, PLEDs were associated with an acute process and occurred early during the course of the illness in all patients studied and were usually associated with structural lesions, with stroke being the main etiology. Traditionally, seizures occur with PLEDs but it is also accepted that they can exist in patients who never develop epileptic activity, either clinically or electrically, as demonstrated in 50% of the patients studied. No significant association between seizures and any etiology could be found. It was not demonstrated that the occurrence of seizures may influence the outcome in any way.  相似文献   
58.
Rising serum tumor markers may be associated with negative imaging in the presence of cancer. CT and (18)F-FDG PET may yield incongruent results in the assessment of tumor recurrence. The present study evaluates the incremental role of (18)F-FDG PET/CT for the diagnosis and management of cancer patients with increasing levels of tumor markers as the sole indicator of potential recurrence after initial successful treatment. METHODS: Thirty-six cancer patients with increasing levels of tumor markers during follow-up and negative CT underwent (18)F-FDG PET/CT, which showed 111 sites of increased tracer uptake. PET/CT was compared with PET results on a site-based analysis for characterization of (18)F-FDG foci and on a patient-based analysis for diagnosis of recurrence. The clinical impact of PET/CT on further patient management was evaluated. RESULTS: Thirty patients (83%) had recurrence in 85 malignant sites (77%). For the site-based analysis, PET had a sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of 96%, 50%, 85%, 85%, and 82%, respectively, as compared with the performance indices of PET/CT of 100%, 89%, 97%, 97%, and 100%, respectively. There was a statistically significant difference between the specificity (P < 0.05) and accuracy (P < 0.001) of PET and PET/CT for precise characterization of suspected lesions. For the patient-based analysis, PET had a sensitivity, specificity, and accuracy of 93%, 50%, and 86%, respectively, as compared with PET/CT with values of 93%, 67%, and 89%, respectively (P = not significant). PET/CT was the single modality that directed further management and treatment planning in 12 patients (33%). CONCLUSION: The results of this study indicate that PET/CT may improve the accuracy of occult cancer detection and further lead to management changes in patients with increasing levels of tumor markers as the sole suspicion of recurrent malignancy.  相似文献   
59.
60.
Prosopagnosia is currently viewed within the constraints of two competing theories of face recognition, one highlighting the analysis of features, the other focusing on configural processing of the whole face. This study investigated the role of feature analysis versus whole face configural processing in the recognition of facial expression. A prosopagnosic patient, SC made expression decisions from whole and incomplete (eyes-only and mouth-only) faces where features had been obscured. SC was impaired at recognizing some (e.g., anger, sadness, and fear), but not all (e.g., happiness) emotional expressions from the whole face. Analyses of his performance on incomplete faces indicated that his recognition of some expressions actually improved relative to his performance on the whole face condition. We argue that in SC interference from damaged configural processes seem to override an intact ability to utilize part-based or local feature cues.  相似文献   
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