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41.
Primitive Neuroectodermal Tumors of the Central Nervous System 总被引:2,自引:0,他引:2
Lucy Balian Rorke M.D. John Q. Trojanowski M.D. Ph.D. Virginia MY Lee Ph.D. Robert A. Zimmerman M.D. Leslie N. Sutton M.D. Jaclyn A. Biegel Ph.D. Joel W. Goldwein M.D. Roger J. Packer M.D. 《Brain pathology (Zurich, Switzerland)》1997,7(2):765-784
Controversial issues relating to the pathobiology and classification of central nervous system primitive neuroectodermal tumors (PNETs) have plagued neuropathologists for more than 70 years. Hypotheses advanced in the mid-1920's have remained as fixed concepts in contemporary literature, largely consequent to repetitious support by a small number of neuropathologists despite a growing body of information discrediting these ideas from neuroembryologists, oncologists, neuroscien-tists and pathologists.
Attention has largely focused upon PNETs arising in the cerebellum (commonly known as medul-loblastomas [MBs]), because about 80% of central nervous system (CNS) PNETs originate in this site. It has been asserted that the 20% which do not are biologically different, although most individuals agree that the histological features of PNETs that occur in different sites throughout the CNS are indistinguishable from those growing in the cerebellum.
The historical aspects of this controversy are examined in the face of evidence that there is, in fact, a unique class of CNS tumors which should appropriately be regarded as primitive neuroectodermal in nature. Specifically, a number of different approaches to the problem have yielded data supporting this hypothesis. These approaches include the identification of patterns of expression among a variety of cellular antigens (demonstrated by the use of immunopathological techniques), molecular analyses of cell lines derived from these tumors, experimental production of PNETs and molecular genetic analyses.
Differences of opinion among surgeons, oncologists and radiotherapists are typically resolved by conducting cooperative studies of patients with these tumors who are diagnosed and treated at multiple centers. 相似文献
Attention has largely focused upon PNETs arising in the cerebellum (commonly known as medul-loblastomas [MBs]), because about 80% of central nervous system (CNS) PNETs originate in this site. It has been asserted that the 20% which do not are biologically different, although most individuals agree that the histological features of PNETs that occur in different sites throughout the CNS are indistinguishable from those growing in the cerebellum.
The historical aspects of this controversy are examined in the face of evidence that there is, in fact, a unique class of CNS tumors which should appropriately be regarded as primitive neuroectodermal in nature. Specifically, a number of different approaches to the problem have yielded data supporting this hypothesis. These approaches include the identification of patterns of expression among a variety of cellular antigens (demonstrated by the use of immunopathological techniques), molecular analyses of cell lines derived from these tumors, experimental production of PNETs and molecular genetic analyses.
Differences of opinion among surgeons, oncologists and radiotherapists are typically resolved by conducting cooperative studies of patients with these tumors who are diagnosed and treated at multiple centers. 相似文献
42.
Helicobacter pylori seropositivity and IL-1B C-31T polymorphism among Japanese Brazilians 总被引:2,自引:0,他引:2
Uno M Hamajima N Ito LS Oba SM Marie SK Shinjo SK Onda H Saito T Takezaki T Tajima K Tominaga S 《International journal of molecular medicine》2002,10(3):321-326
We reported previously that anti-Helicobacter pylori antibody seropositivity (HP+) had an association with interleukin 1B (IL-1B) C-31T genotype, especially among smokers. This study examined the association for Japanese Brazilians. In this cross-sectional study, voluntary participation was announced through Japanese Brazilian communities in Sao Paulo, Curitiba, Mogi das Cruzes, and Mirandopolis; 963 Japanese Brazilians (399 males and 564 females) aged 33-69 years participated. Lifestyle data and peripheral blood were collected. An anti-HP IgG antibody test and genotyping for IL-1B C-31T and IL-1RN 86 bp VNTR were independently conducted. The genotype frequency of the IL-1B polymorphism among 947 individuals was 23.9% for C/C genotype, 45.6% for C/T genotype, and 30.5% for T/T genotype. Sex-age-adjusted odds ratio (aOR) of HP+ was 1.30 (95% confidence interval, 0.94-1.81) for C/T genotype and 1.45 (1.02-2.07) for T/T genotype relative to C/C genotype. The aOR for 127 current smokers was 2.45 (0.91-6.55) for C/T and 3.49 (1.17-10.46) for T/T, while that for 667 never smokers was 1.21 (0.82-1.78) and 1.36 (0.90-2.05), respectively. The corresponding figures were 2.42 (1.16-5.02) and 3.00 (1.33-6.78) for 226 current drinkers, and 1.21 (0.82-1.78) and 1.36 (0.90-2.05) for 667 non-drinkers. The difference in the OR was observed for milk consumption, salty pickled vegetable eating, and physical exercise practice. 4/4 Genotype of IL-1RN 86 bp VNTR was 84.8%, and had no association with the HP seropositivity. The observed association between HP+ and IL-1B -31TT indicated that the genetic trait also influences the susceptibility to HP for Japanese in Brazil. 相似文献
43.
44.
Smoking and Drinking Behavior in Patients with Head and Neck Cancer: Effects of Behavioral Self-Blame and Perceived Control 总被引:4,自引:0,他引:4
Christensen AJ Moran PJ Ehlers SL Raichle K Karnell L Funk G 《Journal of behavioral medicine》1999,22(5):407-418
Patients who continue to use tobacco or alcohol following treatment for head and neck cancers are at greater risk for cancer recurrence and mortality. The present study examined the effects of behavioral self-blame and perceived control over health on smoking and alcohol use in a sample of 55 patients with cancers of the head and neck. Measures of self-blame, perceived control, and depression were administered and an assessment of past and current smoking and drinking behavior was obtained. As anticipated, continued smoking after completion of oncologic treatment was predicted by the interaction of behavior specific self-blame and perceived control. Patients who attributed the cause of their cancer to their past substance use exhibited a lower likelihood of smoking only if they also held the expectancy that their future cancer-related health was contingent on their own behavior. Among patients not holding the belief that cancer recurrence was contingent on their own actions, self-blame was associated with a higher probability of continued smoking. Self-blame and perceived control had no effect on continued alcohol use. 相似文献
45.
P J de Pagter Rob Schuurman Ellen Meijer Debbie van Baarle E A M Sanders J J Boelens 《Journal of clinical virology》2008,43(4):361-366
Human herpesvirus type 6 (HHV6) is known to reactivate after hematopoetic stem cell transplantation (HSCT) and has been suggested to be associated with increased mortality and severe clinical manifestations, including graft versus host disease (GvHD). The exact etiological role of HHV6 reactivation in increased morbidity and mortality after HSCT remains unclear. This review will focus on the current available evidence of HHV6 reactivation after HSCT and its immuno-modulatory capacities, with particular emphasis on the severe complication GvHD. At present, no effective specific antiviral treatment for HHV6 reactivation has been identified. The currently available antiviral agents are outlined, as well as possible future strategies for the treatment of HHV6 reactivation. Non-toxic, specific treatment or prevention of HHV6 reactivation might improve the safety and efficacy of the HSCT procedure. 相似文献
46.
Andrew S Artz Daniel A Pollyea Masha Kocherginsky Wendy Stock Elizabeth Rich Olatoyosi Odenike Todd Zimmerman Sonali Smith Lucy Godley Michael Thirman Christopher Daugherty Martine Extermann Richard Larson Koen van Besien 《Biology of blood and marrow transplantation》2006,12(9):954-964
Comorbidity measurements have recently been used to improve estimation of tolerance to allogeneic hematopoietic cell transplantation (HCT). We sought to determine the independent effect of comorbidity and performance status on HCT outcome and to devise a simple risk classification system for transplant-related mortality. We analyzed 105 consecutively enrolled patients who underwent HCT and received reduced intensity conditioning with fludarabine, melphalan, and alemtuzumab. Comorbid conditions were tabulated using 2 scales, the Charlson Comorbidity Index (CCI) and the Kaplan-Feinstein Scale (KFS). Comorbid conditions were found in 47% of patients by the KFS and in 27% by the CCI (P < .001). Using the Eastern Cooperative Oncology Group Performance Status (PS) scale, 34% had a PS score >0 (range, 0-2). A simple scale combining the KFS and PS enabled separation of high- from low-risk patients, with 6-month cumulative incidences 50% and 15%, respectively for transplant-related mortality (P = .001) and enhanced prognostic power over the CCI alone (P = .018). Prospective studies evaluating more comprehensive functional and comorbidity measurements are warranted. 相似文献
47.
Fetoscopic visualization may be used for the prenatal diagnosis of external structural malformations of the fetus. Objective documentation of these fetoscopic findings would be desirable. The photographic equipment and techniques required for fetoscopic photography have been investigated, and the results of these investigations with standard fetoscopic instruments in current clinical usage are described. The factors evaluated include the light source, camera equipment, camera settings and film. 相似文献
48.
Murine model of pulmonary anthrax: kinetics of dissemination, histopathology, and mouse strain susceptibility 下载免费PDF全文
Lyons CR Lovchik J Hutt J Lipscomb MF Wang E Heninger S Berliba L Garrison K 《Infection and immunity》2004,72(8):4801-4809
Bioweapons are most often designed for delivery to the lung, although this route is not the usual portal of entry for many of the pathogens in the natural environment. Vaccines and therapeutics that are efficacious for natural routes of infection may not be effective against the pulmonary route. Pulmonary models are needed to investigate the importance of specific bacterial genes in virulence, to identify components of the host immune system that are important in providing innate and acquired protection, and for testing diagnostic and therapeutic strategies. This report describes the characteristics of host and Bacillus anthracis interactions in a murine pulmonary-infection model. The infective dose varied depending on the route and method of inoculation. The germination process in the lung began within 1 h of inoculation into the lung, although growth within the lung was limited. B. anthracis was found in the lung-associated lymph nodes approximately 5 h after infection. Minimal pneumonitis was associated with the lung infection, but significant systemic pathology was noted after dissemination. Infected mice typically succumbed to infection approximately 3 to 4 days after inoculation. The 50% lethal doses differed among inbred strains of mice, but within a given mouse strain, neither the age nor the sex of the mice influenced susceptibility to B. anthracis. 相似文献
49.
Temperament as a potential predictor of mortality: Evidence from a 41-year prospective study 总被引:3,自引:0,他引:3
Pirkko L. Graves Lucy A. Mead Nae-Yuh Wang Kung-Yee Liang Michael J. Klag 《Journal of behavioral medicine》1994,17(2):111-126
Psychological factors were hypothesized to influence mortality, in particular, early versus later mortality. To explore the relationship between temperament, a psychological factor, and mortality in a prospective study of 1337 medical students, we constructed a measure portraying three temperament types, using latent class analysis. Death occurred in 113 subjects over 25–41 years of follow-up. In univariate survival analysis, subjects tending to direct tension inward when under stress (Tension-In) had a higher risk of mortality than Tension-Out or Stable types. These associations persisted after adjustment for age, smoking, cholesterol level, and Quetelet Index. The relative risk (RR) of mortality for Tension-In was 1.56 (95% confidence interval, 1.00–2.44) compared with the Stable group. The risk was due entirely to the excess risk in persons under 55 years of age (RR, 2.59; 95% confidence interval, 1.46–4.62); the corresponding risk of death in older persons was 0.66 (0.30–1.48). Thus temperament is a significant risk factor for mortality, in particular, premature death. 相似文献
50.
Factors influencing help seeking in mentally distressed young adults: a cross-sectional survey. 下载免费PDF全文
Lucy Biddle David Gunnell Debbie Sharp Jenny L Donovan 《The British journal of general practice》2004,54(501):248-253
BACKGROUND: Young adults, especially men, are among those least likely to consult healthcare professionals when mentally distressed or suicidal. AIMS: To investigate the help-seeking behaviours of mentally distressed young adults. Design of study: Cross-sectional survey. SETTING: Bristol and surrounding areas, including inner-city, suburban and urban locations. METHOD: A questionnaire was sent to a sample of 3004 young adults aged 16-24 years. This assessed probable mental disorder (using the 12-item general health questionnaire [GHQ-12]), suicidal thoughts (GHQ-28 suicide subscale), and help-seeking behaviours. RESULTS: Most responders who were assessed as having probable mental disorders (GHQ "cases") had not sought help. Help seeking was more common in female GHQ cases than male cases (34.8% and 21.8%,respectively; P = 0.003) and women with suicidal thoughts more commonly sought help than men with suicidal thoughts (41.6% and 30.9%, respectively; P = 0.15). Small proportions of male and female GHQ cases (7.5% and 8.9%, respectively; P = 0.6), and less than one in five responders with suicidal thoughts, had consulted a general practitioner. In more female than male cases, help was sought from family and friends (30.7% and 18.4%, respectively; P = 0.004). GHQ score was the strongest predictor of help seeking. Men had a higher threshold of severity at which they would seek help than women. Recent experience of suicidal thoughts appeared to be a stronger predictor of formal help seeking in mentally distressed women than mentally distressed men. CONCLUSION: Distressed young adults are reluctant to seek help. Men are particularly unlikely to do so unless severely distressed and tend not to seek lay support. Sex differences in help seeking may be important in understanding the high suicide rate for men. 相似文献