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81.
To recover peptides that antigenically and immunogenically mimic the p185HER2 oncoprotein, we selected the phage-peptide libraries pVIII-9aa and pVIII-9aa. Cys using murine monoclonal antibodies (mAb) MGr2 and MGr6, directed against two distinct epitopes of the p185HER2 extracellular domain. Phagedisplayed peptides containing consensus amino acid motifs were recovered and shown to compete specifically for mAb binding on tumor cells that overexpress p185HER2. The deduced amino acid sequence of the peptides suggests that both epitopes defined by the mAb on p185HER2 are discontinuous and that hydrophobic interactions are involved in binding with the mAb. A phage clone displaying the GPLDSLFAQ peptide elicited a specific immune response against the p185HER2 in BALB/c mice, demonstrating that this phage-displayed peptide represents an immunological equivalent of the MGr2 epitope on p185HER2 and might be used as a substitute for this oncoprotein in in vitro and in vivo immunological studies.  相似文献   
82.
Summary The Southern blot hybridization technique has been applied to study the configuration of immunoglobulin and T-cell receptor genes in 6 cases of the so called mediastinal large cell lymphoma with sclerosis. This lymphoma has been recently recognized as a separate entity among non-Hodgkin lymphomas mainly affecting young adult patients. The B-cell origin of this neoplasm was suggested by means of immunohistochemical analysis. However, the immunophenotypical B-cell related markers used do not always exhibit lineage fidelity. The Southern blot analysis demonstrated the presence of unique heavy and k-light chain immunoglobulin gene rearrangements, establishing genotypically their B-cell origin.This work was supported by the Associazione Italiana per la Ricerca sul Cancro, Milano, Italy, and Progetto finalizzato Oncologia (contratto no 86.00461.44), CNR, Rome, Italy. Aldo Scarpa and Maurizio Lestani are supported by a Scholarship from the Associazione Italiana per la Ricerca sul Cancro, Milano, Italy  相似文献   
83.
Gender, suicidality and bipolar mixed states in adolescents   总被引:1,自引:0,他引:1  
BACKGROUND: The purpose of this study was to determine the relationship between mixed states and suicidality among adolescent outpatients presenting with a DSM-IV defined major depressive episode (MDE). METHODS: Two-hundred and forty-seven adolescents meeting the criteria for MDE were screened for the presence of concurrent, intra-MDE hypomania/mania (i.e., mixed states). All patients were asked whether they had current suicidal ideation or had recently attempted any self-destructive physical act associated with the thought of dying (i.e., a suicide attempt). The data were subjected to analysis using univariate logistic regression. RESULTS: One hundred of the 247 (40.5%) adolescents were bipolar type I or type II. Of these, 82% were in mixed states. Of the patients with suicidal ideation, 62.8% were girls, and of those with histories of a suicide attempt, 69.4% were girls. Girls had more than twice the risk of having suicidal ideation (OR=2.2, p=0.004) and nearly 3 times the risk of having histories of a suicide attempt than boys (OR=2.87, p<0.0001). Being in a mixed state per se did not predict either suicidal ideation or a suicide attempt among all of the 247 patients. However, mixed states apparently independently contributed to the risk of (non-fatal) suicidal behavior among girls only. Of the mixed states, girls had nearly 4 times the risk of having made a suicide attempt compared with those without mixed states (OR=3.9, p=0.003). Age, presence of psychotic features and family history of mood disorder had little or no bearing on suicidality. LIMITATIONS: Correlational chart review study, no data collection on Axis I and Axis II comorbidity and adverse life-events. CONCLUSIONS: This report of greater suicidality in adolescent girls in a mixed state parallels the well-known adult literature of high frequency of mixed states in women. The findings are of relevance to the controversy of antidepressants and suicidality in juvenile depressives in that they identify a vulnerable group. In line with earlier suggestions by the senior author [Akiskal, H.S., 1995. Developmental pathways to bipolarity: are juvenile-onset depressions pre-bipolar? J. Am. Acad. Child Adolesc. Psych. 34, 754-763], our data highlight the public health importance of the wider recognition of bipolar mixed states in juvenile patients masquerading as unipolar depression. Finally, it appears to us that it is the failure of our formal nosology on mixed states--rather than the antidepressants per se--which is the root problem in this controversy.  相似文献   
84.
CD10 is expressed in a subset of chromophobe renal cell carcinomas.   总被引:2,自引:0,他引:2  
CD10 has been considered a useful marker in the diagnosis of renal carcinomas, because of its expression in clear cell and papillary renal cell carcinomas and its absence in chromophobe renal cell carcinomas. On the other hand, chromophobe renal cell carcinoma expresses parvalbumin, which is absent in clear cell and papillary renal cell carcinomas. To further address the relevance of these markers, we studied the expression of CD10 and parvalbumin in 42 samples of chromophobe renal cell carcinoma (seven of which had aggressive features, including invasion beyond the renal capsule, renal vein invasion, metastases, or sarcomatoid transformation), 75 clear cell renal cell carcinomas (eight metastatic) and 51 papillary renal cell carcinomas (two metastatic). CD10 was found in 100% of clear cell renal cell carcinomas, 63% of papillary renal cell carcinomas and in all metastatic cases of both types. At variance with previous studies, we found CD10 expression in from 30 to 90% of the neoplastic cells, in 11 of 42 (26%) chromophobe renal cell carcinomas. The CD10-positive cases included five of the seven (71%) chromophobe renal cell carcinoma with aggressive features. Statistical analysis showed significant association of CD10-positive tumors with clinicopathologic aggressiveness (P=0.003) and mitotic figures (P=0.04). Parvalbumin was strongly expressed in all primary and metastatic chromophobe renal cell carcinomas. Western blot analysis was utilized to confirm the expression of both CD10 and parvalbumin in chromophobe renal cell carcinomas.  相似文献   
85.
 Regional cerebral blood flow changes related to the performance of two oculomotor tasks and a central fixation task were compared in ten healthy human subjects. The tasks were: (a) performance of fast-regular saccades; (b) performance of voluntary antisaccades away from a peripheral cue; (c) passive maintenance of central visual fixation in the presence of irrelevant peripheral stimulation. The saccadic task was associated with a relative increase in activity in a number of occipitotemporal areas. Compared with both the fixation and the saccadic task, the performance of antisaccades activated a set of areas including: the superior and inferior parietal lobules, the precentral and prefrontal cortex, the cingulate cortex, and the supplementary motor area. The results of the present study suggest that: (a) compared with self-determined saccadic responses the performance of fast regular, reflexive saccades produces a limited activation of the frontal eye fields; (b) in the antisaccadic task the inferior parietal lobes subserve operations of sensory-motor integration dealing with attentional disengagement from the initial peripheral cue (appearing at an invalid spatial location) and with the recomputation of the antisaccadic vector on the basis of the wrong (e.g., spatially opposite) information provided by the same cue. Received: 20 May 1996 / Accepted: 28 January 1997  相似文献   
86.
The GafChromic film (GCF) MD-55-2, a radiochromic material, was examined for its optical properties through total reflectance and transmittance measurements in visible spectrum (400-700 nm). By using a multilayer model of the film and Kubelka-Munk's (KM) theory, absorption and scattering coefficients of the film sensitive layer (K and S, respectively) were obtained from measurements of irradiated and nonirradiated slides. This has allowed calculation of the absorbance A(KM) of the sensitive layer of the GCF. The model easily splits scattering from absorption. Unlike absorption, scattering is essentially insensitive to irradiation dose and decreases slowly as the wavelength increases. The scattering effect is predominant over absorption in the 400-500 nm range, while beyond 600 nm absorption prevails. The A(KM) absorbance of the sensitive layer was calculated using the K coefficient and compared with the optical densities (OD) measured considering only ballistic photons (as in a standard spectrophotometer) as well as the optical densities measured collecting all the transmitted photons (as in many densitometers). The values of A(KM) found were always lower than OD measured by the other methods and they had the best linearity on the whole visible range. These data support the hypothesis that the sensitive layer reacts to irradiation more linearly than that shown by measurements using standard commercial devices. However, in the 600-680 nm range, correction is not very important because absorption is predominant over scattering. When GCF is used for imaging, scattering produces a loss of spatial information. Consequently, it is necessary to collect only ballistic photons and to correct absorbance by K and S coefficients.  相似文献   
87.
OBJECTIVE: To evaluate the influence of a brief period of sleep deprivation on cardiac autonomic controls during sleep in healthy infants. DESIGN: Twelve healthy infants with a median age of 8 weeks (range, 7 to 18 weeks) were recorded polygraphically during a morning and an afternoon nap in a sleep laboratory. They were sleep deprived for approximately 2 hours, either in the morning or in the afternoon, before being allowed to fall asleep. Six infants were sleep deprived before the morning nap, and 6 before the afternoon nap. During both naps, their sleep, breathing, and heart-rate characteristics were continuously recorded. Spectral analysis of heart rate was evaluated as a function of sleep stages. Two major peaks were recognizable: a low-frequency component related to sympathetic and parasympathetic activities and a high-frequency component reflecting parasympathetic tonus. The ratio of low-frequency to high-frequency powers was calculated as an index of sympathovagal interaction. RESULTS: When sleep deprived, the infants had an increase in basal heart rate during non-rapid eye movement sleep (P=.021). With sleep deprivation, the ratio of low-frequency to high-frequency powers increased in non-rapid eye movement sleep (P=.005). These findings were consistent with an increase in sympathetic tone. CONCLUSION: Infants exposed to short-term sleep deprivation manifest changes in cardiac autonomic controls during sleep. These findings could be relevant to mechanisms associated with the sudden infant death syndrome.  相似文献   
88.
Dissecting aneurysms of coronary arteries are a rare finding and have never been reported in a cardiac allograft. We found two spontaneous dissecting aneurysms on the middle third of both the left anterior descending and the right coronary arteries in a female cardiac transplantation recipient. She died 43 days after cardiac transplantation after developing human cytomegalovirus pneumonia and pancreatitis. Dissecting coronary aneurysms, microfoci of subendocardial coagulative necrosis, and area of subepicardial dystrophic calcifications were discovered at necropsy examination.  相似文献   
89.
BACKGROUND: Infection with human papillomavirus (HPV) is a necessary step in the progression to cervical cancer. Many methods for HPV testing are currently available, most developed to detect pools of HPV types. OBJECTIVES: To evaluate the HPV typing by molecular methods and to compare commercial kits with an established laboratory method. STUDY DESIGN: Eighty-four cervical samples found to be positive for HPV DNA by GP5+/6+-polymerase chain reaction-enzyme immunoassay-reverse line blotting (PCR-EIA-RLB) were re-tested with two commercial methods, INNO-LiPA and Amplisense HPV typing, able to identify the HPV type predicted by PCR-EIA-RLB in 76 and 67 samples, respectively. RESULTS: The INNO-LiPA assay revealed HPV DNA in 75/76 samples (98.7%; 95% CI, 0.93-0.99) that would contain HPV types identifiable by this assay. The Amplisense HPV assay revealed HPV DNA in 58/67 samples (86.6%; 95% CI, 0.76-0.93) containing HPV types detectable by this assay. For samples with a single infection, the unweighted kappa for concordance of HPV typing was 0.87 (95% CI, 0.78-0.97) for PCR-EIA-RLB versus INNO-LiPA, 0.94 (95% CI, 0.87-0.99) for INNO-LiPA versus Amplisense HPV, and 0.82 (95% CI, 0.70-0.94) for PCR-EIA-RLB versus Amplisense HPV typing. PCR-EIA-RLB revealed 12 multiple infections, INNO-LiPA revealed 14, and Amplisense HPV revealed 5. The agreement among tests for samples with multiple infections was lower, giving kappa values of 0.44 (95% CI, 0.18-0.70) for PCR-EIA-RLB versus INNO-LiPA, 0.52 (95% CI, 0.19-0.85) for PCR-EIA-RLB versus Amplisense HPV and 0.43 (95% CI, 0.12-0.74) for INNO-LiPA versus Amplisense HPV. CONCLUSIONS: In HPV-positive samples, the agreement among tests for HPV typing was high for single infections but markedly lower for infections with multiple HPV types.  相似文献   
90.
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