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目的探讨骨性Ⅲ类错手术与非手术边缘病例的颅面特征,为选择临床治疗方法提供参考。方法选择完成治疗的骨性Ⅲ类错边缘病例,单纯正畸组13例,手术治疗组12例,统计分析2组病例治疗前的X线头影测量值。结果Mann-Whitneyu检验显示2组下颌骨前颅底长度比Go-Me/S-N(P=0.026)、上下颌切牙的交角U1-L1(P=0.030)、Holdaway角(P=0.026)的差异有统计学意义,逐步判别分析后仅有Holdaway角能对2组进行预测区分,区分值为12°,总判别准确率为72%。结论制定骨性Ⅲ类错边缘病例治疗计划时,下颌骨前颅底长度比、上下颌切牙的交角以及软组织的凹陷度是要重点分析的颅面结构项目,小于12°的Holdaway角可以作为需手术改善软组织侧貌的初步判定指标。 相似文献
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Background
Abnormal NF-??B2 activation has been implicated in the pathogenesis of multiple myeloma, a cancer of plasma cells. However, a causal role for aberrant NF-??B2 signaling in the development of plasma cell tumors has not been established. Also unclear is the molecular mechanism that drives the tumorigenic process. We investigated these questions by using a transgenic mouse model with lymphocyte-targeted expression of p80HT, a lymphoma-associated NF-??B2 mutant, and human multiple myeloma cell lines.Methods
We conducted a detailed histopathological characterization of lymphomas developed in p80HT transgenic mice and microarray gene expression profiling of p80HT B cells with the goal of identifying genes that drive plasma cell tumor development. We further verified the significance of our findings in human multiple myeloma cell lines.Results
Approximately 40% of p80HT mice showed elevated levels of monoclonal immunoglobulin (M-protein) in the serum and developed plasma cell tumors. Some of these mice displayed key features of human multiple myeloma with accumulation of plasma cells in the bone marrow, osteolytic bone lesions and/or diffuse osteoporosis. Gene expression profiling of B cells from M-protein-positive p80HT mice revealed aberrant expression of genes known to be important in the pathogenesis of multiple myeloma, including cyclin D1, cyclin D2, Blimp1, survivin, IL-10 and IL-15. In vitro assays demonstrated a critical role of Stat3, a key downstream component of IL-10 signaling, in the survival of human multiple myeloma cells.Conclusions
These findings provide a mouse model for human multiple myeloma with aberrant NF-??B2 activation and suggest a molecular mechanism for NF-??B2 signaling in the pathogenesis of plasma cell tumors by coordinated regulation of plasma cell generation, proliferation and survival. 相似文献35.
Al-Delaimy WK Stampfer MJ Manson JE Willett WC 《American journal of epidemiology》2008,167(11):1342-1348
The authors assess the ability of toenail nicotine levels as a biomarker to predict incident coronary heart disease (CHD). A nested case-control study was carried out among 62,641 women aged 36-61 years in the Nurses' Health Study cohort who provided toenail clippings in 1982. Between 1984 and 1998, 905 incident CHD cases were diagnosed and matched with two controls by age and date of toenail collection. Using multivariate logistic regression analyses, the authors found a statistically significant dose-response association between increasing toenail nicotine levels and risk of CHD (p(trend) < 0.0001); women in the highest quintile had a relative risk of 3.44 (95% confidence interval (CI): 2.56, 4.62) compared with women in the lowest quintile. With each increase in the log-transformed unit of continuous toenail nicotine levels, there was a 42% increase in the risk of CHD (relative risk = 1.42, 95% CI: 1.33, 1.52). The association remained significant when the number of cigarettes smoked and passive smoking were included as covariates (relative risk = 1.12, 95% CI: 1.01, 1.24). In conclusion, toenail nicotine levels are predictive of CHD among women independent of other risk factors and remained significant even after adjustment for history of cigarette smoking. 相似文献
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Al-Delaimy WK Natarajan L Sun X Rock CL Pierce JP Pierce JJ;Women's Healthy Eating Living 《Epidemiology (Cambridge, Mass.)》2008,19(2):338-344
BACKGROUND: The reliability of biomarkers profoundly impacts validity of their use in epidemiology and can have serious implications for study power and the ability to find true associations. We assessed reliability of plasma carotenoid levels over time and how it could influence study power through sample size and effect-size. METHODS: Plasma carotenoid levels were measured in a cohort study of 1323 women participating in the control arm of the Women's Healthy Eating and Living Study. We compared mean plasma levels at baseline, year 1, and year 4 of the study for alpha-carotene, beta-carotene, lycopene, lutein, and beta-cryptoxanthin. Reliability of these levels over time was assessed by Spearman correlations and intraclass correlation. RESULTS: We found limited variation in mean levels between any 2 time points. Variation did not exceed 8% for lycopene, lutein, and beta-cryptoxanthin, 15% for alpha-carotene, and 18% for beta-carotene. Spearman correlations for individual carotenoids over time varied between 0.50 and 0.80, with lycopene having the lowest correlation. Intraclass correlations ranged from 0.47 to 0.66 for carotenoids. CONCLUSION: Intraclass correlations for plasma carotenoids over a period of several years are acceptable for epidemiologic studies. However, such variation is enough to decrease statistical power and increase the sample size needed to detect a given effect. 相似文献
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Cynthia A. Thomson Cheryl L. Rock Bette J. Caan Shirley W. Flatt Wael A. Al-Delaimy Vicky A. Newman 《Nutrition and cancer》2013,65(1):11-19
Consumption of cruciferous vegetables has been associated with reduced breast cancer risk mechanistically and in population-based studies, although evidence has been inconsistent. This inconsistency may be related to limitations in quantifying and qualifying cruciferous vegetable exposure using standard instruments for dietary assessment (for example, food-frequency questionnaires, FFQs) or due to low levels of intake demonstrated among U.S. population samples. Cruciferous vegetable intake data are presented from a longitudinal study of a high-vegetable dietary intervention to reduce breast cancer recurrence among breast cancer survivors (n = 1,156; 536 intervention and 620 comparison group subjects). Intake was assessed using repeat administration of an FFQ and cross-sectional administration of a cruciferous vegetable–specific FFQ (CVFFQ). Mean intake in the intervention group assessed using the standard FFQ was 37.7 g/day at baseline and increased to 57.1 g/day at 12 mo (P = 0.0001) and was sustained through 48 mo. Broccoli and cabbage were the most commonly consumed cruciferous vegetables, regardless of the instrument used to assess intake. Differences in intake by group assignment were shown for raw cruciferous vegetables (30.2 g/day vs. 24.6 g/day, assessed using the CVFFQ), suggesting increased exposure to biologically active, cancer-preventive food constituents. These data suggest that this study population will be the first U.S. population sample to provide ample quantity and variety in cruciferous intake to examine whether these vegetables are protective against breast cancer recurrence. 相似文献
40.
The Queensland Sport and Recreation Injury Survey (QSRIS) is a retrospective study describing the annual incidence of injuries in the state of Queensland, Australia, resulting from sport and recreational activity involvement. Data were collected by means of a computer-assisted-telephone-interview (CATI) survey of a representative sample of Queenslanders in the spring of 2000. The sample produced a total of 1337 respondents aged 18 to 94 years. The survey asked information regarding medically attended, non-fatal injuries resulting from sport and recreational activities in the past 12 months. Of the 1337 individuals surveyed, 191 of the respondents reported one or more injuries that required medical attention resulting in a total of 222 Injuries. This represents an overall rate of 1,666 medically attended injuries per 10,000 people. Among those reporting a sport or recreational injury, the most common types of injuries were a strained/pulled muscle (30.9%), sprained/torn ligament (24.1%), and fracture (12.6%). The most common bodily locations of injuries were the shoulders (13.0%) and knees (12.5%). Results detail the nature and type of injury, medical professional attending to the injury and the nature of the sport or recreational activity that led to the reported injury, highlighting the number of injuries associated with general fitness activities achieved through high participation rates and low injury rates. This remains an area of much needed attention given the promotional push towards raising the levels of physical activity at a population level. 相似文献