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Breast cancer screening is offered to BRCA1 and BRCA2 mutation carriers from the age of 25 years because of their increased risk of breast cancer. As ovarian cancer screening is not effective, risk-reducing salpingho-oophorectomy (RRSO) is offered after child bearing age. RRSO before menopause reduces the breast cancer risk as well as breast density. It can be questioned whether after premenopausal RRSO, the intensive breast cancer screening program needs modification. We evaluated the effectiveness of breast cancer screening by clinical breast examination (CBE), mammography, and MRI in a population of 88 BRCA1 and 51 BRCA2 mutation carriers who had RRSO before the age of 52. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each screening modality. During 422 women years, 14 breast cancers were diagnosed; 2 prevalent, 10 screen detected and 2 interval breast cancers (12 in BRCA1 and 2 in BRCA2 mutation carriers). Sensitivity, specificity, PPV, and NPV for the combined screening were 85.7%, 97.6%, 30.0%, and 99.8%, respectively. No tumors were found with CBE, MRI had a sensitivity of 60.0% and mammography of 55.6%. Off all the tumors, 60% were node positive. Effectiveness of CBE and mammography was comparable to earlier findings. MRI screening seemed less effective than earlier findings. After RRSO, the breast cancer risk in BRCA1 and BRCA2 mutation carriers is still high enough to justify intensive breast cancer screening with MRI and mammography.  相似文献   
203.
The ways in which resources are allocated within households and/or families, especially within the context of children's time allocation to labor and schooling, has long been a subject of concern to demographers and economists. Differential investment in children and resulting differences in activity budgets may have significant effects on children's growth and development as well as on aspects of reproduction. This study uses predictions regarding parental investment in the embodied capital of offspring generated by evolutionary theory to examine the pattern of children's time allocation to labor and schooling among the Okavango Delta Peoples of Botswana. Models incorporating individual costs and benefits of resource allocation, conflicts of interests between men and women and between parents and offspring, and the effects of family composition, subsistence ecology, and gender are developed and applied to data on time allocation, household demography, and household economy. Several findings emerged: (1) The availability of alternative productive tasks strongly affects intra‐ and intergenerational labor substitution. (2) The presence of similarly aged children of the same sex within the household decreases the likelihood of both boys and girls engaging in a specific productive activity and increases the likelihood of children's school attendance. (3) Birth order, the labor needs of the household, and parents’ marital status all affect school attendance. These results have implications for understanding the determinants of children's time allocation to labor and schooling and consequent impacts on development, health, and welfare. Am. J. Hum. Biol. 14: 206–221, 2002.© 2002 Wiley‐Liss, Inc.  相似文献   
204.
In aging brain, degenerative as well as compensatory regenerative processes are believed to occur. The neural cell adhesion molecule NCAM is involved in developmental and regenerative processes in the brain. However, the role of NCAM in aging brain has not been characterized. In this study, the expression of NCAM mRNAs and polypeptides was investigated in aging rat brain. The 7.4 and 6.7 kb NCAM mRNAs were selectively downregulated during postnatal development, and the 5.2 and 2.9 kb NCAM mRNAs were upregulated. However, from postnatal day 40 to old age no change in NCAM mRNA classes was observed. The fraction of NCAM mRNA containing the VASE exon increased postnatally but remained stable during adult life. VASE, which is believed to modulate the binding capacity, seemed to be relatively more abundant in the 7.4 and 6.7 kb NCAM mRNAs, encoding transmembrane NCAM forms, than in the 5.2 and 2.9 kb NCAM mRNAs, coding for glycosyl phosphatidylinositol (GPI) linked NCAM. Conversely, insertion of exons a and AAG between exons 12 and 13, a region containing two fibronectin type III repeats, seemed to be more pronounced in 5.2 and 2.9 kb NCAM mRNAs than in the 7.4 and 6.7 kb mRNAs. During postnatal development an increase in the fraction of 6.7 kb NCAM mRNA containing the exons a and AAG was observed. However, during aging the fraction of NCAM mRNAs containing this exon combination seemed constant. At the protein level, NCAM-A was downregulated both during development and aging. No changes were observed during aging in the composition of soluble NCAM forms in the brain, cerebrospinal fluid or blood plasma. The amount of NCAM in rat brain decreased during postnatal development, but remained at a constant level from postnatal day 40 to old age.To conclude, several changes in NCAM expression occur during early postnatal development emphasizing the important role of this molecule in the morphogenetic processes. During aging, a significant selective downregulation of NCAM-A was observed indicating that in general only minor regenerative processes occur in the brain.  相似文献   
205.
Systemic and superficial fungal infections are a major problem among immunocompromised patients with hematological malignancy. A double-blind, double-placebo, randomized, multicenter trial was performed to compare the efficacy and safety of itraconazole oral solution (2.5 mg/kg of body weight twice a day) with amphotericin B capsules (500 mg orally four times a day) for prophylaxis of systemic and superficial fungal infection. Prophylactic treatment was initiated on the first day of chemotherapy and was continued until the end of the neutropenic period (>0.5 x 10(9) neutrophils/liter) or up to a maximum of 3 days following the end of neutropenia, unless a systemic fungal infection was documented or suspected. The maximum treatment duration was 56 days. In the intent-to-treat population, invasive aspergillosis was noted in 5 (1.8%) of the 281 patients assigned to itraconazole oral solution and in 9 (3.3%) of the 276 patients assigned to oral amphotericin B; of these, 1 and 4 patients died, respectively. Proven systemic fungal infection (including invasive aspergillosis) occurred in 8 patients (2.8%) who received itraconazole, compared with 13 (4.7%) who received oral amphotericin B. Itraconazole significantly reduced the incidence of superficial fungal infections as compared to oral amphotericin B (2 [1%] versus 13 [5%]; P = 0.004). Although the incidences of suspected fungal infection (including fever of unknown origin) were not different between the groups, fewer patients were administered intravenous systemic antifungals (mainly intravenous amphotericin B) in the group receiving itraconazole than in the group receiving oral amphotericin B (114 [41%] versus 132 [48%]; P = 0.066). Adequate plasma itraconazole levels were achieved in about 80% of the patients from 1 week after the start of treatment. In both groups, the trial medication was safe and well tolerated. Prophylactic administration of itraconazole oral solution significantly reduces superficial fungal infection in patients with hematological malignancies and neutropenia. The incidence of proven systemic fungal infections, the number of deaths due to deep fungal infections, and the use of systemic antifungals tended to be lower in the itraconazole-treated group than in the amphotericin B-treated group, without statistical significance. Itraconazole oral solution is a broad-spectrum systemic antifungal agent with prophylactic activity in neutropenic patients, especially for those at high risk of prolonged neutropenia.  相似文献   
206.
PURPOSE: We assessed the cost-effectiveness of mammography screening for women under the age of 50, from breast cancer families without proven BRCA1/BRCA2 mutations, because current criteria for screening healthy women from breast cancer families are not evidence-based. METHODS: We did simulation studies with mathematical models on the cost-effectiveness of mammography screening of women under the age of 50 with breast cancer family histories. Breast cancer screening was simulated with varying screening intervals (6, 12, 18, and 24 months) and screening cohorts (starting at ages 30, 35, 40, and 45, and continuing to age 50). Incremental costs of screening were compared with those of women ages 50 to 52 years, the youngest age group currently routinely screened in the nationwide screening program of the Netherlands, to determine cost-effectiveness. Sensitivity analyses were done to explore the effects of model assumptions. The cost-effectiveness of breast cancer screening for women over the age of 50 was not debated. RESULTS: The most effective screening interval was found to be 12 months, which, however, seems only to be cost-effective in a small group of women under the age of 50 with at least two affected relatives, including at least one affected in the first degree diagnosed under the age of 50. Significantly, early breast cancer screening never seemed to be cost-effective in women with only one affected first-degree or second-degree relative. CONCLUSION: Annual breast cancer screening with mammography for women under the age of 50 seems to be cost-effective in women with strong family histories of breast cancer, even when no BRCA1/BRCA2 mutation was found in affected family members.  相似文献   
207.

Background  

High mobility group box-1 (HMGB1) is a newly recognized factor regulating cancer cell tumorigenesis, expansion and invasion. We investigated the correlation between the serum HMGB1 levels and the clinical and pathologic features of gastric cancer and evaluated the validity of HMGB1 as a potential biomarker for the early diagnosis of gastric cancer.  相似文献   
208.
209.
L-selectin mediates lymphocyte migration to peripheral lymph nodes and leukocyte rolling on vascular endothelium during inflammation. One unique feature that distinguishes L-selectin from other adhesion molecules is that it is rapidly cleaved from the cell surface after cellular activation. The biological significance of L-selectin endoproteolytic release was determined by generating gene-targeted mice expressing a modified receptor that was not cleaved from the cell surface. Blocking L-selectin cleavage on antigen-stimulated lymphocytes allowed their continued migration to peripheral lymph nodes and inhibited their short-term redirection to the spleen. Blocking homeostatic L-selectin cleavage also resulted in a constitutive 2-fold increase in overall L-selectin expression by leukocytes. As a result, neutrophils entered the inflamed peritoneum in greater numbers or for a longer duration. Thus, endoproteolytic cleavage regulates both homeostatic and activation-induced changes in cell surface L-selectin density, which directs the migration patterns of activated lymphocytes and neutrophils in vivo.  相似文献   
210.
Background: Healthcare workers have an increased risk of occupational dermatoses. In January 2002, the Department of Social Medicine, Occupational and Environmental Dermatology of the University of Heidelberg started organizing special prevention courses for this group of employees in cooperation with the Accident Prevention & Insurance Association for Health Care Workers (BGW). The major aims are to improve individual skin protection and skin care habits, as well as to optimize diagnostic procedures and therapy. Patients and Methods: The two‐day course has up to 14 participants. Teaching units mainly focus on skin structure and function, general aspects of occupational skin diseases, general information concerning skin protection and practical exercises emphasizing the correct use of skin cleansing and skin protection products. Additionally, every participant undergoes a dermatological examination including a detailed history and skin inspection. Individual skin protection strategies are developed, and the participants are provided with the opportunity to ask the dermatologist questions in confidence. Results: Most of the 355 participants have been female (87,3 %) with a mean age of 36,9 years. 95 % had hand eczema, predominantly dyshidrotic morphology. In many cases, there was a mixture of atopic, irritant and allergic contact dermatitis but irritant contact dermatitis was most common (43 %). Atopy was present in 68 % of the patients. The participants rated the course as good to excellent. Other benefits are the exchange of experience between patients working in the same or similar occupations and transfer of the new knowledge to colleagues, family and friends. Conclusions: Examinations and advisory services in occupational dermatology are still fragmentary. Skin barrier creams and moisturizers are not sufficiently utilized in daily practice. In the future, similar courses should be offered for employees in other professions with an increased risk of occupational skin diseases.  相似文献   
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