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The prefrontal cortex is strongly engaged by some, but not all, episodic memory tests. Prior work has shown that source recognition tests--those that require memory for conjunctions of studied attributes--yield deficient performance in patients with prefrontal damage and greater prefrontal activity in healthy subjects, as compared to simple recognition tests. Here, we tested the hypothesis that there is no intrinsic relationship between the prefrontal cortex and source memory, but that the prefrontal cortex is engaged by the demand to retrieve weakly encoded relationships. Subjects attempted to remember object/color conjunctions after an encoding task that focused on object identity alone, and an integrative encoding task that encouraged attention to object/color relationships. After the integrative encoding task, the late prefrontal brain electrical activity that typically occurs in source memory tests was eliminated. Earlier brain electrical activity related to successful recognition of the objects was unaffected by the nature of prior encoding.  相似文献   
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AimsTo assess the awareness of risk factors for type 2 diabetes and lifestyle changes that can decrease such risks in women with GDM.MethodsThe study comprised responses to health questionnaires by 319 women: 31 pregnant women with current GDM (CGDM), 88 women with previous GDM (PGDM), 100 pregnant women without DM (PWDM) and 100 non-pregnant women without DM (NPWDM). The CGDM group answered the questionnaires at the initiation and 4 weeks after participating in formal education on GDM. Two types of awareness scores (AS) were established. One AS was about the risks associated with GDM (GDMR), and the other was related to the awareness of lifestyle changes that can decrease the risks of type 2 diabetes (DM2R).ResultsThe PGDM group had the highest GDMR and DM2R scores (9.55 ± 2.66) (13.2 ± 2.26) compared with the other groups (CGDM 7.48 ± 3.14, NPWDM 6.10 ± 3.17, PWDM 2.89 ± 2.48) (p < 0.05) and (NPWDM 12.05 ± 2.73, CGDM 11.29 ± 2.45, PWDM 8.27 ± 4.14) (p < 0.05). The CGDM group increased the GDMR score from 7.48 ± 3.14 to 10.54 ± 2.57 (p < 0.0001) and the DM2R score from 11.29 ± 2.45 to 14.04 ± 1.26 (p < 0.001).ConclusionsWomen had limited awareness of risk factors for type 2 diabetes and lifestyle modifications that can decrease such risk of diabetes. AS were higher in women with current and previous GDM after receiving formal education.  相似文献   
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The adverse effect of treatment prolongation in cervical carcinoma   总被引:3,自引:0,他引:3  
: Proliferation of surviving tumor clonogens during a course of protracted radiation therapy may be a cause of local failure in cervical carcinoma. The effect of total treatment time was analyzed retrospectively in relation to pelvic control and overall survival for squamous cell carcinomas of the uterine cervix.

: Two hundred and nine patients (Stage IB-IIIB) treated with a combination of external beam and low dose rate intracavitary irradiation were evaluable for study. Multivariate analysis and Kaplan-Meier statistical methods were used to determine the effect of treatment time on pelvic control and survival at 5 years.

: The median treatment duration was 55 days. For all stages combined, the 5-year survival and pelvic control rates were significantly different with treatment times < days vs. ≥ 55 days 65 and 54% (p = 0.03), 87 and 72% (p = 0.006), respectively. By stage, a shorter treatment duration (i.e., < 55 days vs. ≥ 55 days) was significant for 5-year overall survival and pelvic control for Stages IB/IIA and III, but not for Stage IIB: Stage IB/IIA (81 and 67%, and 84%), Stage III disease (52 and 42%, 76 and 55%) and Stage IIB (43 and 50%, 74 and 80%, respectively). Survival decreased 0.6%/day and pelvic control decreased 0.7%/day for each additional day of treatment beyond 55 days for all stages of disease. Additionally, significantly late complications were not influenced by treatment time.

: These results that prolongation of treatment time is associated with decreased local control and survival in patients with cervical carcinoma. This is consistent with emerging data from other institutions. Therapeutic implications include avoidance of unnecessary treatment breaks, the design of fractionation schemes that decrease treatment duration, and possibly the use of tumor cytostatic drugs during conventional radiation.  相似文献   

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Because the potential urban yellow fever (YF) mosquito vectors Aedes aegypti and Ae. albopictus are at historical highs in Brazil, both in terms of density and geographical range, we assessed the risk of an urban YF epidemic in Brazil. We evaluated and confirmed in a laboratory setting the vector competence of Brazilian Ae. aegypti for a currently circulating strain of YF virus, and investigated the potential for Brazilian Ae. albopictus to transmit YF.  相似文献   
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Body mass and stage of breast cancer at diagnosis   总被引:9,自引:0,他引:9  
Obesity is a well-known risk factor for postmenopausal breast cancer. In contrast, the relationship between obesity and stage of breast cancer at diagnosis is less clear. We hypothesized that increased breast size in obese women may delay discovery of breast tumors. Thus, the purpose of our study was to examine whether there is an association between body mass and stage of breast cancer at diagnosis using hospital medical records. Newly diagnosed breast cancer cases (n = 966) in the Baltimore metropolitan area from 1991 to 1997 were included in our study. Patient information including age, ethnicity, weight, height and pathology data were obtained from hospital medical records. High body mass was significantly associated with late stage of breast cancer at diagnosis. Women who were obese (body mass index [BMI] > or = 27.3) were more likely to be at an advanced stage at diagnosis compared with women with a BMI of < 27.3 (multivariate-adjusted odds ratio [OR] 1.57, 95% confidence interval [CI] 1.15-2.14). The association between body mass and stage at diagnosis was stronger among women younger than 50 years (OR 2.34, 95% CI 1.34-4.08) compared with women 50 years or older (OR 1.30, 95% CI 0.89-1.91). Our study suggests that higher body mass is associated with advanced stage of breast cancer at diagnosis. This finding may be of considerable concern, given the increasing prevalence of obesity in women in the United States and the poor prognosis associated with late-stage tumors.  相似文献   
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We report an unusual case of aggressive ALK-positive anaplastic large cell lymphoma with widespread mediastinal involvement immediately preceded by an acute Epstein-Barr virus (EBV) infection. Following initiation of chemotherapy and radiological evidence of significant tumor regression, the patient suffered a fatal massive upper gastrointestinal hemorrhage from an aorto-esophageal fistula. The relevant literature relating to EBV in the pathogenesis of ALK-lymphomas and literature relating to aorto-enteric fistula (AEF) in mediastinal lymphoma is reviewed.  相似文献   
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