目的 探讨利用荧光激活细胞分选技术获得有效重组逆转录病毒包装细胞系的方法。方法 用脂质体介导pLEGFP转染PA317细胞用荧光显微镜观察转染结果：依据EGFP荧光利用流式细胞仪的分选技术获得多克隆和单克隆源性的包装细胞。并利用PCR、RT-PCR对其鉴定；以NIH3T3为靶细胞。对其滴度进行测定。结果 荧光显微镜显示用脂质体介导的方法成功的转染PA317细胞在4次连续流式细胞仪分选后得到了稳定表达的多克隆和单克隆源性的包装细胞。PCR和RT-PCR分别从多克隆和单克隆源性的包装细胞细胞基因组DNA以及多克隆和部分（6/8）单克隆源性的包装细胞培养上清中的重组逆转录病毒RNA中扩增出了插入的EGFP片段。滴度测定显示得到的包装细胞能够产生有效的病毒滴度。结论 荧光激活细胞分选技术是获得有效病毒滴度的包装细胞的有效方法。

目的：构建BMP2/pLEGFP重组逆转录病毒表达载体，并检测其表达的融合蛋白的生物活性。方法：用基因重组技术构建BMP2/pLEGFP重组逆转录病毒表达载体，并通过酶切和PCR鉴定。脂质体法转染COS27细胞，用荧光显微镜检测和Western blotting分析其在COS27细胞表达，细胞活性实验和动物体内异位成骨实验进一步检测融合蛋白的生物活性。结果：经酶切和PCR鉴定重组质粒BMP2/LEGFP构建成功。转染COS27细胞后，荧光显微镜和Western blotting检测均显示融合蛋白在细胞中表达；分泌的产物经细胞活性实验和动物体内异位成骨实验证实具有BMP2和EGFP的双重蛋白活性。结论：基因重组技术成功构建BMP2/pLEGFP重组体，重组体表达的融合蛋白具有GFP和BMP2的双重活性。

Objective To analyze the genetic polymorphism of 6 STR loci (D12S358, D12S1675, D12S1663, D12S1697, D12S1725 and D12S1613) on chromosome 12 in Chinese Han population. Methods EDTA-blood specimens were collected from 153 unrelated individuals of Chinese Han population in Shaanxi province. Allele and genotype frequencies for the 6 STR loci were estimated and statistical parameters of polymorphism were calculated. Re sults 8 alleles and 18 genotypes, 10 alleles and 17 genotypes, 9 alleles and 15 genotypes, 12alleles and 29 genotypes, 12 alleles and 31 genotypes, 8 alleles and 11 genotypes were observed at D12S358, D12S1675, D12S1663, D12S1697, D12S1725 and D12S1613, respectively. No deviations of the observed allele frequency from Hardy-weinberg equilibrium expectations were found for any of these loci. The Heterozygotes of these 6 loci were 78.89%, 66.10%, 54.95%, 79.10%, 71.98% and 59.48%, respectively. It indicated the high genetic polymorphism of the loci in Chinese Han population. Conclusion The 6 STR loci belonged to the genetic marker system of high discriminutesation and high information in Chinese Han population and can be used in the study of gene-related diseases.

Concentrations of selenium (Se), boron (B), and germanium (Ge) were determined in scalp hair of children with Kashin-Beck disease (KBD), in healthy children in KBD-disease endemic areas, and in healthy children in non-KBD areas. Mean Se, B, and Ge concentrations were low in children with KBD; in hair of healthy children in KBD areas, Se levels were normal but B and Ge levels were lower than in KBD-free areas. The hair levels of B and Ge were unaffected by selenium supplementation. It is suggested that B and Ge deficiency may be contributing factors in the etiology of KBD.