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81.
Stephen Hunter Terry Gramlich Karen Abbott Vijay Varma 《Genes, chromosomes & cancer》1993,8(3):172-177
Carcinoma of the esophagus shows a strong male predominance and other epidemiologic differences from cancers arising at other sites. In this study, the prevalence of Y chromosome loss in 29 carcinomas of the esophagus and 53 carcinomas arising elsewhere in the aerodigestive tract was assessed by in situ hybridization of formalin-fixed paraffin-embedded tissue sections. Absence of the Y chromosome was defined as (1) negative staining for Y in neoplastic cells with positive staining for Y in immediately adjacent nonneoplastic epithelial and stromal cells, (2) positive staining of neoplastic cells with control probes for chromosomes X and 17, and (3) similar results at different stringencies and levels of protein digestion. According to these criteria, absence of the Y chromosome was observed in 13 of 14 (93%) adenocarcinomas of the esophagus, 8 of 13 (62%) squamous cell carcinomas of the esophagus, and 5 of 53 (9%) carcinomas arising in other sites. For the neoplasms examined, Y chromosome deletion was strongly and selectively associated with carcinomas, particularly adenocarcinomas, of the esophagus (P < .0001). These findings suggest that Y chromosome loss may be pathogenetically significant in these neoplasms. © 1993 Wiley-Liss, Inc. 相似文献
82.
E M Hunter 《The Australian and New Zealand journal of psychiatry》1988,22(3):264-271
Aboriginal suicide has become an issue receiving national attention because of the association with "deaths in custody". To date little systematic work has been directed to the investigation of suicide among a non-incarcerated Aboriginal population. This paper focuses on deaths by suicide within one geographical area. It identifies two factors, alcoholism and disruption of interpersonal attachments, which may play a causal role in male Aboriginal suicide. The sudden emergence of suicide in this partial descent population, in concert with suicides among incarcerated and non-incarcerated Aborigines elsewhere, suggests that socio-historical forces must be examined to further clarify the phenomenon. 相似文献
83.
Variability in portion sizes of commonly consumed foods among a population of women in the United States 总被引:1,自引:0,他引:1
D J Hunter L Sampson M J Stampfer G A Colditz B Rosner W C Willett 《American journal of epidemiology》1988,127(6):1240-1249
The use of food frequency questionnaires for measuring dietary intake has become widespread in epidemiologic studies. It has been suggested that inquiring about a person's usual serving size of each food, in addition to the frequency of consumption, will improve the accuracy of this method. This approach implies that individuals characteristically eat a specific amount of any particular food, and that this amount can be reported with reasonable accuracy. To investigate the variability of portion sizes, the authors analyzed data for 68 commonly consumed foods, based on four one-week weighed diet histories recorded by 194 Boston-area women aged 34-59 years during 1980 and 1981. For each food, total population variance in portion size was partitioned into within-person (intraindividual) and between-person (interindividual) components. For all but seven food items (yogurt, liver, mixed vegetables, watermelon, pancakes/waffles, cold cereal, and cooked cereal) the within-person variance in portion size exceeded the between-person variance. The mean of the within-person to between-person variance ratios, after exclusion of two outlying foods, was 3.4 for untransformed portion sizes, and 3.2 after portion sizes were loge-transformed. Foods with a high within-person variance also tended to have a high between-person variance. The dominance of within-person variance in portion sizes suggests that the concept of usual portion size is complex, and that subjects may experience substantial difficulty in specifying their "usual" portion size. The smaller contribution of between-person variance to the total variance in portion size suggests that specification of a standard portion size by the investigator may not introduce a large error in the estimation of food and nutrient intake. 相似文献
84.
Clinical applications of electrical stimulation for effecting change in the damaged or disabled nervous system are in their infancy. This technique is extremely powerful, because any neural structure that is electrically excitable can potentially be affected. Although early attempts to apply electrical stimulation were limited by insufficient physiological knowledge and undeveloped technology, developments over the past two decades now provide a strong base for clinical applications. Clinical systems for bladder control and respiration have been in use for many years. Some applications of FES to restore hand function and walking are in multicenter testing, whereas many others are being studied for clinical feasibility at single sites. Applications are focusing on safety and efficacy, as well as on clinical outcome measures to address the issues posed by the regulatory and reimbursement processes. As clinical systems become more routine, issues of multiple system applications will need to be addressed. Present and future applications of functional electrical stimulation may be expected to significantly enhance independence and improve the quality of life for individuals with central nervous system dysfunction. 相似文献
85.
The clinical course and outcome of 111 patients with tricuspid atresia, seen during 1972-1982, were reviewed. All clinical and investigation data, progress and management were analysed. The mean age at presentation was 21.9 +/- 8.8 days. Patients with reduced pulmonary blood flow presented earlier. Patients with normal or increased pulmonary blood flow usually presented in heart failure. "True" natural history was observed in 13 unoperated patients. Six of these died at the age of 7 days to 8 months (mean 32.2 days). Seven patients survived without surgery for 11 months to 24 years, the older ones developing pulmonary vascular obstructive disease. The overall mortality in the whole series was 32.4% (36/111), the mean age at death was 3.1 years (range 3 days-48 years). The mortality rate within the first year of life was 22.5%. The mean age of survivors at follow-up was 10.7 +/- 0.9 years (range 11 months-27 years). 相似文献
86.
Pearman P Hunter G Hendricks C O'Sullivan P 《The Journal of orthopaedic and sports physical therapy》1989,10(11):451-455
This study investigated the effect of dehydration on measurements of body composition by hydrostatic weighing (HW) and bioelectric impedance analysis (BIA). Ten endurance-trained male athletes between the ages of 18 and 42 years performed an endurance training session consisting of running until body weight was reduced by approximately 3%. Body composition was determined prior to exercise and immediately after exercise by HW and BIA techniques. A high correlation existed between pre- and postdehydration for both HW and BIA. Validity coefficients between HW and BIA were moderate (predehydration 0.85 and postdehydration 0.82). In addition, BIA percent fat was 3.5% higher than HW percent fat. The BIA revealed a mean loss of 2.1% fat BIA and only 0.9% fat HW after approximately 45 minutes of exercise. BIA also showed an increase in percent body water (mean = 2.6%) in all 10 subjects after dehydration. There are indications that BIA, with its present equational configuration, is measuring something other than lean body weight. J Orthop Sports Phys Ther 1989;10(11):451-455. 相似文献
87.
Optic nerve pseudomeningioma secondary to localized amyloidosis 总被引:1,自引:0,他引:1
A 55-year-old woman presented with a mass of the optic nerve sheath suggestive of a meningioma. On excision, this proved to be amyloid. No systemic involvement could be found. Although amyloid may arise as a solitary lesion of the orbit or extraocular muscle, this "pseudomeningiomatous" pattern has not been previously noted. A magnetic resonance scan was helpful because the amyloid imaged at a density similar to vitreous and cerebral white matter, unlike meningiomas, which appear more like bone. The diagnosis of localized amyloidosis, however, still remains dependent on histopathology and cannot be made on a clinical basis. 相似文献
88.
Sperm-agglutinating antibodies were present in three (2-6%) of 117 fertile men and in 19 (33-9%) of 56 men who had been vasectomized. Twenty-four of the 56 vasectomized men had been studied before vasectomy; sperm-agglutinating antibodies were present in one (4-3%) compared with eight (33-3%) after vasectomy. No sperm-immobilizing antibodies were detected before vasectomy but were present in 10 (17-9%) of the 56 men after vasectomy. 相似文献
89.
H. Zola H. A. Moore I. K. Hunter A. Hohmann P. J. Mcnamara J. Bradley P. Mum A. Morley J. V. Melo D. Catovsky 《Tissue antigens》1985,26(1):60-70
FMC3 and FMC29 are monoclonal antibodies which react with a 30,000 Dalton molecule expressed on the lymphocyte surface membrane. The molecule is a protein which does not appear to be N-glycosylated. The antigen, which is also expressed intracellularly, does not appear to be a marker of differentiation or maturation. Polyclonal cell populations, such as peripheral blood lymphocytes, show a bimodal distribution of surface antigen density, whilst monoclonal cell populations analysed quantitatively showed unimodal antigen density distributions. This suggests the antigen may be a clonal marker. 相似文献
90.
The relationship between cytotoxicity and prognostically significant histologic changes in lymph nodes from patients with cancer of the breast.
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Axillary lymph nodes obtained from 37 patients with cancer of the breast were used in a microcytotoxicity assay against a human mammary cancer cell line, ALAB. Cell suspensions made from 60 individual lymph nodes and 51 lymph node pools were tested. Each lymph node was graded for the extent of the histologic changes of sinus histiocytosis (SH), paracortical hyperplasia (PCH), and germinal center hyperplasia (GCH). High levels of cytotoxicity correlated significantly with the presence of SH and PCH. When multiple lymph nodes of individual patients were pooled and tested, a high intensity of GCH correlated with a low degree of cytototoxicity. The cytotoxic activity of pooled lymph nodes from different axillary regions was studied in 20 patients. In 7 of these patients, low axillary lymph node cells were more cytotoxic than high axillary node cells. The reverse was found for 7 patients, and there was no difference in cytotoxicity between axillary regions in 6. Cytotoxic lymph node pools had high SH and low GCH whether they were obtained from the low or high region. Noncytotoxic lymph node pools from the high axillary region had a low intensity of all three histologic reactions. In contrast, noncytotoxic lymph node pools from the low axillary regions had high intensities of SH, PCH, and GCH. These results suggest that germinal center hyperplasia in the lymph nodes nearest an advancing tumor is associated with a local suppression of cytotoxic cell activity. 相似文献