MPO和NAT2基因多态性与成人急性白血病易感性

目的研究髓过氧化物酶（MPO）和N-乙酰基转移酶2（NAT2）基因多态性与成人急性白血病易感性的关系.方法用1∶1配对病例-对照研究方法,收集成人急性白血病患者和对照各139例,应用聚合酶链-内切酶片段（PCR-RFLP）方法分析病例组和对照组MPO和NAT2的基因多态性,比较不同基因型与成人急性白血病易感性.结果 MPO-463A等位基因分布频率病例组低于对照组,MPO（G-463A）各基因型在病例组与对照组中的分布差异有统计学意义（χ^2=7.026,P〈0.05,OR=0.505,95%CI=0.325～0.847）.NAT2乙酰化表型频率在病例组与对照组的分布差异无统计学意义（χ^2=2.260,P〉0.05）;但NAT2＊5 481T等位基因和NAT2＊6 590A等位基因分布频率病例组高于对照组（P〈0.05）.结论 MPO与成人急性白血病易感性相关,携带MPO（G-463A）突变基因型（GA/AA）个体可降低白血病的发病风险;NAT2乙酰化表型可能与白血病的易感性无关,但NAT2＊5（C481T）、NAT2＊6（G590A）单核苷酸突变频率病例组明显高于对照组.     

17β-雌二醇对大鼠脊髓损伤后神经保护作用的研究

目的：探讨17β-雌二醇（E2）对大鼠脊髓损伤（SCI）后的神经保护作用及其机制。方法：应用改良的Allen′s重物打击法建立大鼠急性脊髓损伤模型,将大鼠随机分为两组：A组（PBS对照组）和B组（E2治疗组）,每组42只,B组造模成功后15min及24h腹腔注射E2（4.0mg/kg,以PBS溶解）,A组在相同时间给予等量无菌PBS。分别于伤后7d、14d、21d及28d,应用改良Tarlov评分法和Rivlin斜板试验评价大鼠脊髓神经功能恢复情况。于伤后6h、24h、3d、7d、14d及28d时处死动物,以损伤部位为中心取材,HE染色观察脊髓组织病理变化,TUNEL法染色检测细胞凋亡,免疫组化染色检测caspase-3、Bcl-2的表达情况。结果：从伤后14d起,B组Tarlov评分和斜板试验角度与A组相比差异有显著性（P〈0.01）。TUNEL法检测表明,大鼠SCI后存在细胞凋亡,3d时达高峰,与caspase-3的表达基本一致,B组伤后24h、3d及7d时凋亡细胞比率显著低于A组（P〈0.01或P〈0.05）。免疫组化结果显示B组伤后24h、3d、7d、14d及28d时caspase-3表达低于A组（P〈0.01或P〈0.05）,而Bcl-2表达高于A组（P〈0.01或P〈0.05）。结论：E2能促进大鼠SCI后的神经功能恢复,具有一定的神经保护作用;E2可能是通过减少SCI后继发性细胞凋亡的机制发挥作用的。     

Iowa's High School High Tech Goes to College Program: Preparing Students with Mild Disabilities for Careers in Technology

This paper describes an innovative approach to preparing high school students with mild disabilities for challenging careers in high tech industries, called High School High Tech (HSHT). Iowa's HSHT Goes to College program has three central elements, each of which is discussed in this paper: High School Preparation—assisting students in identifying a suitable high tech career goal; Higher Education Preparation and Supports—assisting students in selecting college/training programs that match their career goal, and in successfully completing their postsecondary programs; Workforce Entry Assistance—linking students with employers and launching their high tech careers. The paper concludes with a presentation of outcomes to date and recommendations for program enhancements. The information presented here is intended to assist education and rehabilitation professionals interested in establishing similar efforts across the nation.     

三氧化二砷纳米微粒对抑制兔血管平滑肌细胞增殖作用的实验研究

目的 了解纳米微粒与普通剂型的三氧化二砷（As2O3）对抑制体外培养的兔血管平滑肌细胞（VSMC）增殖作用的差别。方法 对照组为不加药物的细胞，实验组为3μmol／L纳米微粒和普通剂型的As2O3，干预体外培养的兔VSMC细胞72h，进行四唑氮盐（MTT）染色测定细胞吸光度（A）值。用流式细胞仪检测细胞凋亡情况，提取细胞DNA，进行凝胶电泳分析，将3组的结果进行比较。结果 3μmol／L纳米剂型的As2O3，干预细胞，细胞数量随作用时间的延长逐渐减少，细胞生长明显受抑制，而普通剂型干预细胞，生长受抑制程度较纳米剂型弱。24h时，对照组、3μmol／L普通剂型组与纳米组，A值分别为0．68±0．10、0．58±0．12、0．33±0．12，48h时分别为0．79±0．11、0．48±0．14、0．28±0．11，72h时分别为0．96±0．13、0．34±0．15、0．20士0．06，差异均有统计学意义（Ⅳ值分别为10．934、15．039、15．539，P值均〈0．01）。流式细胞仪检测，纳米剂型As2O3、普通剂型As2O3干预及对照组的细胞干预48h，细胞增殖率分别为44．97％、58．54％、74．02％，早期凋亡率分别为16．89％、11．27％、11．20％，晚期凋亡率分别为26．56％、23．60％、12．46％，坏死细胞分别为11．58％、6．59％、2．32％。DNA电泳，As2O3干预细胞，可见凋亡梯形条带，部分细胞坏死，呈模糊的无间隔片状条带。纳米剂型药物作用的细胞DNA条带，梯形条带更多、更模糊。结论 As2O3，可以抑制体外培养的VSMC增殖，且纳米剂型As2O3较普通剂型的As2O3，对细胞抑制作用更强。     

计算机X线摄影图像的静止滤线栅伪影分析

目的通过分析计算机X线摄影（CR）系统的采样频率和栅密度频率，提出尽可能有效避免滤线栅伪影出现的抑制方法。方法实际测试不同栅密度的滤线栅与不同规格的成像板（IP）匹配使用，得到不同效果的图像；模拟2种信号频率（即2种栅密度的滤线栅），采用3种采样频率[6、8、10图像空间分辨率（pixels／mm）]，得到不同的模拟图像效果。结果通过对比分析模拟图和实际图像，发现在采样频率正好等于信号频率的2倍时，可以得到正确的信号频率，图像清晰，无混淆现象。栅密度〈4LP／mm时，可较好地与14in×14in、10in×12in（1in=2．54cm）IP匹配使用。结论CR系统与普通IP匹配使用合适的采样频率和栅密度频率，可以有效避免滤线栅伪影出现。     

An exploration of gifted programs

This article presents findings on an exploration of gifted programs in the state of Missouri. Over 60 percent of the state supported public school gifted programs participated in the study. The study concludes that the guidelines for gifted education in Missouri create extreme variability in the standards of the programs. Strong national policy for gifted education is needed to insure gifted children are properly served and protected by law.     

An analysis of the deep social structure preventing the development of a national policy for children and families in the United States

The United States is one of the few economically developed nations without a national policy supporting children and their families. This paper suggests that the United States has a unique national ideology, based on the “Calvinistic Ethic,” which results in opposition to not only social programs for children and families, but to all government supported welfare programs. Such an ethic is not found in European countries. Finally, since the United States does not have a national family policy, millions of children and their families go without health care, lack social services, and suffer from inadequate economic supports.     

咳嗽从肾论治

基于中医有关古代文献和个人的临床经验，作者举例说明咳嗽不仅能从肺治疗，从肾治疗也是行之有效的方法。