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991.
Pantelis C Harvey CA Plant G Fossey E Maruff P Stuart GW Brewer WJ Nelson HE Robbins TW Barnes TR 《Psychological medicine》2004,34(4):693-703
BACKGROUND: Behavioural syndromes (thought disturbance, social withdrawal, depressed behaviour and antisocial behaviour) offer a different perspective from that of symptomatic syndromes on the disability that may be associated with schizophrenia. Few studies have assessed their relationship with neuropsychological deficits. We hypothesized that these syndromes may represent behavioural manifestations of frontal-subcortical impairments, previously described in schizophrenia. METHOD: Long-stay inpatients (n=54) and community patients (n=43) with enduring schizophrenia were assessed, using measures of symptoms and behaviour and tests of executive functioning. The relationship between syndromes and neuropsychological function was assessed using multiple regression and logistic regression analyses. RESULTS: Significant associations were found between performance on the spatial working memory task and the psychomotor poverty symptomatic syndrome, and between attentional set-shifting ability and both disorganization symptoms and the thought disturbance behavioural syndrome. These results were not explained by the effect of premorbid IQ, geographical location, length of illness or antipsychotic medication. Length of illness was an independent predictor of attentional set-shifting ability but not of working memory performance. CONCLUSION: The specific relationship between negative symptoms and spatial working memory is consistent with involvement of the dorsolateral prefrontal cortex. The associations between difficulty with set-shifting ability and both disorganization symptoms and behaviours may reflect inability to generalize a rule that had been learned and impaired ability to respond flexibly. The specific relationship of illness duration to set-shifting ability may suggest progressive impairment on some executive tasks. The nature of these relationships and their neurobiological and rehabilitation implications are considered. 相似文献
992.
Flat and polypoid adenocarcinomas of the colorectum: A comparative histomorphologic analysis of 47 cases 总被引:2,自引:0,他引:2
Nasir A Boulware D Kaiser HE Bodey B Siegel S Crawley S Yeatman T Marcet JE Coppola D 《Human pathology》2004,35(5):604-611
"Flat" colorectal adenomas and adenocarcinomas are well documented in the Japanese literature but only sporadically reported in the English literature. The present study involved systematic morphological analysis of a large series of colorectal carcinomas (CRCs) to determine the frequency of these "flat" CRCs (FCRCs) and analyze their pathological characteristics and associated patient survival. The study group comprised 47 patients (19 females and 28 males) with primary CRC who underwent colorectal resection at the H. Lee Moffitt Cancer Center between 1997 and 2002. These cases were selected based on the gross appearance of the tumors and after review of all of the hematoxylin and eosin-stained tumor sections in a series of 190 consecutive colorectal resections for CRCs. Application of strict morphological criteria classified 22 tumors as FCRCs. For comparison, 25 "polypoid" CRCs (PCRCs) were also identified. Cases of ulcerative fungating annular CRCs and CRCs with mixed gross appearance were excluded from this analysis. Clinicopathologic data, including patient survival, were compared for FCRCS and PCRCs. Statistical analyses were carried out using the chi(2) or Fisher's exact test and log-rank tests. Overall, 22 of 190 CRCs (11%) were found to meet the morphological criteria of FCRCs. Mean patient age was 70.6 years (range, 55 to 87) for FCRCs versus 68.5 years (range, 54 to 91) for PCRCs, and mean tumor size was 4.7 cm (range, 1.6 to 9) for FCRCs versus 4.4 cm (range, 0.5 to 10) for PCRCs. None of the 22 FCRCs and only 1 of 25 (4%) PCRCs were well differentiated; 17 of 22 (77%) FCRCs and 23 of 25 (92%) PCRCs were moderately differentiated; and 5 of 22 (22%) FCRCs and 1 of 25 (4%) PCRCs were poorly differentiated (P = 0.0087). FCRC cases were staged as 0 stage T1, 3 (14%) stage T2, and 19 (86%) stage T3; PCRC cases, as 4 (16%) stage T1, 14 (56%) stage T2, and 7 (28%) stage 3 (P = 0.000031). Similarly, angiolymphatic invasion was identified in 12 of 22 (54%) FCRCs versus 4 of 25 (16%) PCRCs (P = 0.0123). Although some differences between FCRCs and PCRCs were observed on resection in terms of nodal status (N), presence of metastases (M), and perineural invasion, these differences were not statistically significant. In comparison with PCRCs, FCRCs were associated with significantly shorter postresection patient survival at 1 to 5 years (P = 0.028). We have demonstrated in this report that a proportion of primary CRCs resected at our institution were indeed "flat." Furthermore, these FCRCs exhibited higher histological grades, higher T stage, more frequent angiolymphatic invasion, and shorter patient survival compared with PCRCs. Based on these data, FCRC appears to be a worse subtype of colon cancer than PCRC. Further appraisal of FCRCs and additional studies to further elucidate the molecular mechanisms underlying their morphogenesis are warranted. 相似文献
993.
We provide a general framework for describing various roles for biomarkers in cancer prevention research (early detection, surrogate endpoint, and cohort identification for primary prevention) and the phases in their evaluation. 相似文献
994.
Avidity of antibodies to cytomegalovirus in HIV-seropositive patients with and without CMV retinitis
Marshall BC Jacobson MA Adler SP;Studies Of Ocular Complications Of AIDS Research Group 《Viral immunology》2004,17(1):101-108
Antibodies of high avidity may protect the fetus from CMV infection, but the association of avidity with other CMV infections is unknown. To determine if anti-CMV antibody avidity is altered in HIV-seropositive patients, either untreated or treated with HAART, and to determine if alterations in avidity are associated with CMV retinitis, we obtained sera from 164 CMV-seropositive adults: 68 were HIV-seronegative healthy adults and 96 were HIV seropositive. Of the HIV-positive, 57 had no current or prior evidence of CMV retinitis (29 were being treated with HAART, and 28 were receiving no therapy when sampled), and 39 had either active CMV retinitis or were immunorestored by HAART with quiescent CMV retinitis. IgG antibody avidity was determined for each serum run in duplicate using an EIA assay and 5M urea as a dissociating agent. After correction for the significantly higher levels of IgG antibodies to CMV in the HIV-seropositive sera as compared to the normal healthy individuals, both HIV-infected and HIV-uninfected individuals had nearly identical average avidity indices (avidity index = 76). There was also no significant difference in average avidity index between HAART-treated and untreated patients, or between patients with active and immunorestored, quiescent CMV retinitis). These results indicate antibody avidity is unaltered in HIV disease and does not play an important role in the pathogenesis of AIDS-related CMV disease. 相似文献
995.
BACKGROUND: The OM6 is a 6-item condition-specific handicap measure developed in the United States for children with recurrent acute otitis media and otitis media with effusion. Easy and quick to use, it has high test-retest repeatability and is sensitive to change after ventilation tube insertion. OBJECTIVES: To explore aspects of the validity of OM6 in a United Kingdom population and to specifically address the instrument's ability to discriminate between children with different burdens of disease. DESIGN: The parents of 179 consecutive newly referred children with otitis media with effusion or recurrent acute otitis media completed the OM6 on their first visit to the hospital. The parents of 72 children with sore throats completed the OM6 for comparison. Scores were compared with markers of disease severity, demographic variables, and generic quality-of-life measures. RESULTS: Poorer scores were found in those with ear complaints than in those with sore throats. The OM6 scores were not associated with age, sex, socioeconomic class, or respondent (mother vs father). The OM6 scores did not correlate with frequency of otalgia, frequency of otorrhea, or time off school in the recurrent acute otitis media group. In the otitis media with effusion group, poorer scores were associated with bilateral B or C2 tympanometric findings but not with a better ear threshold of more than 20 dB. Correlation with a global 10-cm visual analog scale for quality of life and with the Health Utilities Index Mark III was good. CONCLUSIONS: The OM6 scores correlate well with global quality-of-life measures and are free from many potential biases. However, OM6 does not adequately reflect disease severity, which may limit its usefulness as a discriminative measure. 相似文献
996.
Stuart A 《American journal of audiology》2004,13(1):23-28
The equivalency of Lists 1 to 4 of the Northwestern University Auditory Test No. 6 (NU-6; T. W. Tillman and R. Carhart, 1966) was investigated in interrupted broadband noise. Forty-eight young adults with normal hearing participated. All lists were administered at 50 dB sensation level re: listener spondee recognition thresholds at signal-to-noise ratios (S/Ns) of 10, 5, 0, -5, -10, -15, -20, -25, and -30 dB. Significant differences in listener performance were observed only at S/Ns ranging from 10 to -10. Significant mean list differences varied from 5.8% to 12.0%. These findings support the notion that caution should be exercised in the interpretation of listener performance differences with NU-6 stimuli presented in a background of interrupted noise. 相似文献
997.
This 4-year project investigated the pass/refer rates of preschool children in a hearing screening program. Three- and 4-year-old children who attended Head Start centers in rural, traditionally medically underserved, eastern North Carolina participated (n = 1,462). Screening procedures and pass/refer criteria were based on the Guidelines for Audiologic Screening (American Speech-Language-Hearing Association [ASHA], Panel on Audiologic Assessment, 1997). Only 54% (n = 787) of children passed the initial screening (i.e., passed all three of the screening components, which included pure-tone audiometry, tympanometry, and otoscopy), and an additional 22% (n = 323) passed the rescreening, for an overall pass rate of 76%. The initial pass rate was 90%, 71%, and 71% for otoscopy, tympanometry, and pure-tone audiometry, respectively. After the initial screening, 675 children were referred (i.e., 83%, 2%, and 15% for audiologic rescreening, medical evaluation, or both, respectively). About 71% (n = 478) received the recommended evaluation. Follow-up assessment compliance after the rescreening was poor. Slightly more than 10% of children were evaluated. The hearing status of 267 (i.e., 18.3%) children was never determined. Six (i.e., 0.5%) of the 1,195 children who completed the audiologic screening and/or received diagnostic audiologic assessment were confirmed to have hearing loss. Methodological factors that may have contributed to this high refer rate include the use of all screening techniques (pure tones, tympanometry, and otoscopy), procedural considerations in testing protocol and pass/refer criteria, and the demographic characteristics of the children screened. 相似文献
998.
The purpose of this study was to investigate distortion product otoacoustic emissions (DPOAEs) and outer/middle ear status in 12 African American children with normal hearing and homozygous sickle cell disease (SCD) and age-, gender-, and ear-matched African American controls. C. R. Downs, A. Stuart, & D. Holbert (2000) reported that DPOAE amplitudes were significantly larger for children with SCD. Because the integrity of the middle ear system directly influences OAE characteristics, it was felt that concurrent investigation of DPOAE amplitudes and outer/middle ear function in children with SCD was warranted. DPOAEs were evoked by 13 primary-tone pairs with f2 frequencies ranging from 1000 to 4500 Hz. Outer/middle ear status was assessed with tympanometry through indices of peak compensated static acoustic admittance, tympanometric width, tympanometric peak pressure, ear canal volume, and middle ear resonance frequency. Tympanograms were recorded with probe-tone frequencies of 226 and 678 Hz. DPOAE amplitudes were significantly larger for children with SCD (p < .05). There were no group differences in any of the middle ear indices (p > .05). These findings suggest that increased DPOAE amplitudes for children with SCD cannot be attributed to differences in outer/middle ear function as assessed with tympanometry. 相似文献
999.
There are many conceptual and practical difficulties in teaching culturally sensitive issues to student nurses. There is little clear evidence about the most effective way that the subject of racism can be explored in the classroom setting. This critical appraisal is a collation of the evidence as a means of identifying current practice and the theoretical difficulties and debates that characterise this area. The evidence is based on English language material, largely if not exclusively, from the United States of America and the United Kingdom. We used CINAHL 1982-2003 and MEDLINE 1993-2003 using the search terms 'curriculum', 'education', 'nursing', 'teaching', 'minority groups', 'race relations', 'prejudice', and 'ethnic groups'. The central tension lies between a multicultural and an anti-racist approach, which reflects philosophically diverse opinions about what should be included in the nursing curriculum. The outcome of this tension is reliant on providing evidence about the experiences of students and tutors and whether the problem is one of difficulties in cross-cultural communication or racism. Recommendations from the literature for the teaching of multiculturalism and/or anti-racism are synthesised and discussed in light of the tension existing between the two philosophies. 相似文献
1000.
Hot cooking oil burns resulted in 316 admissions to the Burns Unit at The Royal Brisbane Hospital between January 1, 1981, and December 31, 2000. Notable demographics of this group were a male:female ratio 1.74:1 and that 24% of all patients were between the ages of 16 and 20. Workplace burns accounted for 6% of admissions only, but these tended to be of a larger total body surface area involvement. The mean duration of admission was 8.5 days, with 40% of patients undergoing surgical débridement and split-skin grafting. Two hundred thirty-nine patients had 5% or less TBSA burned, most commonly involving the hands, legs, feet, and the forearms. No patients in our study died. The proportion of patients undergoing débridement and grafting increased from zero patients at commencement of this study to a peak of 82.5% in 1998. We believe this reflects changing practice with earlier excision and grafting trying to achieve the best functional and cosmetic results. The lack of predisposing factors and the accidental nature of these burns mean appropriate prevention strategies are paramount to decreasing the number of burns of this type. Suggestions discussed include school-based education programs, warning labels included in product information, and mandatory fire blankets within the home. 相似文献