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991.
对33例初诊骨髓增生异常综合征病人的骨髓涂片及骨髓活检进行分析,表明涂片在初诊筛选中能对MDS作出诊断,而骨髓活检对判断增生度,显示各系病态造血,提供预后信息及确诊MDS合并骨髓纤维化中意义重大,后者对前者起补充、修正的作用. 相似文献
992.
993.
Sensorineural deafness inherited as a tissue specific mitochondrial disorder. 总被引:7,自引:0,他引:7 下载免费PDF全文
L Jaber M Shohat X Bu N Fischel-Ghodsian H Y Yang S J Wang J I Rotter 《Journal of medical genetics》1992,29(2):86-90
We present here a large Israeli-Arab kindred with hereditary deafness. In this family 55 deaf subjects (29M, 26F), who are otherwise healthy, have been identified and traced back five generations to one common female ancestor. The deafness is progressive in nature, usually presenting in infancy and childhood. Audiometry on six deaf and seven unaffected subjects was consistent with severe to profound sensorineural hearing loss. Based on formal family segregation analysis, the inheritance of deafness in this family closely fits the expectation of a two locus model owing to the simultaneous mutation of a mitochondrial gene and an autosomal recessive gene. Thus, this disorder appears to have the unusual features of being an inherited tissue specific mitochondrial disease and apparently requiring the homozygous presence of a nuclear gene for clinical expression. Most importantly, this disorder presents a unique opportunity to investigate the molecular basis of hereditary non-syndromic deafness and normal hearing. 相似文献
994.
National examinations for medical graduates were introduced on an experimental basis in the People's Republic of China in 1982. To estimate the predictive validity of the National Medical Examination (NME), an investigation of the postgraduate competence of a sample of the participating examinees was conducted in 1984. The sample consisted of 1,717 of the 4,995 graduates from 13 medical colleges who had taken the initial NME. Their scores on the NME and the ratings given them by directors of postgraduate programs in nine aspects of clinical competence were compared by frequency distribution and product-moment correlation coefficients. Scores on the NME were consistent with measures of postgraduate clinical competence and, as a whole, correlated significantly with the ratings of clinical competence, supporting the use of the score on the NME as a predictor of postgraduate clinical competence. However, the extent of the relationship between the NME score and postgraduate clinical competence varied according to the specialty program of postgraduate medical training. 相似文献
995.
深入探讨长骨骨折愈合塑形阶段的力学机理,采用骨表面再造理论与有限元结合的方法。我们选取用应变能密度作为力学激励的骨表面再造理论,有限元分析采用三维的空间模型,利用我们编制的长骨表面再造系统“BRSS97”对长骨骨折愈合塑形阶段的三种类型:外骨痂型、骨内缺损型和骨外缺损型的力学机理进行研究。结果表明:骨痂可以完全吸收,骨缺损可以恢复,三种情况下骨均可以恢复到正常状态。由此说明长骨骨折愈合塑形过程就是骨材料对力学激励的适应过程。 相似文献
996.
Priming with Chlamydia trachomatis major outer membrane protein (MOMP) DNA followed by MOMP ISCOM boosting enhances protection and is associated with increased immunoglobulin A and Th1 cellular immune responses 下载免费PDF全文
We previously reported that DNA vaccination was able to elicit cellular immune responses and partial protection against Chlamydia trachomatis infection. However, DNA immunization alone did not generate immune responses or protection as great as that induced by using live organisms. In this study, we evaluated the immunologic effects of a combinational vaccination approach using C. trachomatis mouse pneumonitis (MoPn) major outer membrane protein (MOMP) DNA priming followed by boosting with immune-stimulating complexes (ISCOM) of MOMP protein (MOMP ISCOM) for protection of BALB/c mice against MoPn lung infection. Substantially better protection to challenge infection was observed in mice given combinational vaccination compared with mice given MOMP ISCOM immunization alone, and the protection approximated that induced by live organisms. Enhanced protection was correlated with stronger delayed-type hypersensitivity, higher levels of gamma interferon production, and increased immunoglobulin A antibody responses in lung homogenates. The results indicate that DNA priming followed by ISCOM protein boosting may be useful in designing a fully protective chlamydial vaccine. 相似文献
997.
Jiang S Xin R Wu X Lin S Qian Y Ren D Tang G Wang D 《American journal of medical genetics》2000,96(3):289-292
Attention deficit hyperactivity disorder (ADHD) is a prevalent disorder in children. The etiology of this disease is not clear. Genetics studies have suggested the involvement of the dopamine DRD-4 receptor gene and dopamine transporter gene (DAT1). Clinical studies have shown that monoamine oxidase-B (MAO-B) inhibitors are effective in the treatment of ADHD. These findings suggest that monoamine oxidase (MAO) genes might be involved in the origin of ADHD. In the present work, the DXS7 locus of chromosome X, which is closely linked to MAO genes, was selected as a marker to study the possible association between ADHD and MAO genes in the Chinese population. Haplotype-based haplotype relative risk (HHRR) and the transmission disequilibrium test (TDT) methods were employed to analyze the association and the linkage disequilibrium, respectively. Significant association (X(2) = 15.86; 1 df; P < 0.001) and linkage (X(2) = 14.88; 1 df; P < 0.001) were detected between the 157-bp allele of the DXS7 locus and the DSM-III-R-diagnosed ADHD (N = 72) in trios composed of father, mother, and affected offspring. The data suggested that ADHD was associated and in linkage with DXS7 locus. 相似文献
998.
妊娠期糖尿病与瘦素水平变化的临床研究 总被引:4,自引:0,他引:4
目的 探讨瘦素水平与妊娠期糖尿病 (GDM)发病关系以及对其胎儿生长发育的影响。方法 采用放射免疫法测定GDM孕妇 2 0例 ,糖耐量减低 (IGT)孕妇 2 2例 ,正常孕妇 2 5例血清及其新生儿脐血的瘦素水平 ,同时测定这三组孕妇的胰岛素、C肽水平 ,并测量孕前体重指数和孕期体重增加指数 ,分析其与瘦素之间的关系。结果 GDM孕妇血清瘦素、胰岛素和C肽水平明显高于IGT组及正常组 (P <0 .0 0 1)。脐血瘦素水平与胎儿体重呈正相关 (P <0 .0 5 ) 。孕妇血清瘦素水平与胎儿体重无相关。孕妇血清瘦素水平与脐血瘦素水平无相关。GDM孕妇血清瘦素与孕前体重指数明显相关 (P <0 .0 5 ) ,与孕期体重增加指数无相关。结论 (1)GDM孕妇血清瘦素水平明显高于正常孕妇 ,故瘦素可作为监控GDM的指标之一。(2 )GDM孕妇瘦素水平与脐血瘦素水平虽然不相关 ,提示胎儿瘦素是自身产生 ,但母亲糖尿病也可以影响胎儿产生更多的瘦素。 相似文献
999.
Lü XY Huang Y Qian WP Tang ZM Lu ZH 《Journal of biomedical materials research. Part A》2003,66(3):722-727
An effective method for the quantitative evaluation of proteins adsorbed on biomaterial surfaces has been developed. First, the kinetic behavior of a range of human fibrinogen (Fib) adsorbed onto polystyrene (PS) films was investigated by using a reflectometry interference spectroscopy setup. The specific molecular number of adsorbed proteins, N(p,) was then defined. According to the definition, the numbers of Fib molecules adsorbed on PS films were calculated. An atomic force microscope (AFM) was used to scan the lateral distribution of the Fib molecules adsorbed on the PS films. From the AFM images, the practical specific molecular numbers were obtained by direct counting of the molecules. In order that the adsorbed number of Fib molecules on a unit area of the PS films could be counted easily, the solution concentration of proteins was reduced to 5 ag/mL (10(-18)g/mL). There was good consistency between the numbers calculated with the formula defined by us and the numbers counted from AFM images. Therefore, the results of the present study prove the validity of our definition of the specific molecular number of adsorbed proteins and the effectiveness of the reflectometry interference spectroscopy-based method for quantitative evaluation of adsorptive proteins. 相似文献
1000.
Germ cell transplantation: a review and progress report on ICSI from spermatozoa generated in xenogeneic testes 总被引:3,自引:0,他引:3
Sofikitis N Kaponis A Mio Y Makredimas D Giannakis D Yamamoto Y Kanakas N Kawamura H Georgiou J Schrader M Lolis E Giannakopoulos X Loutradis D Tarlatzis V Miyagawa I 《Human reproduction update》2003,9(3):291-307
Results from the transplantation of donor male germ cells into xenogeneic recipient seminiferous tubules indicate that donor spermatogonia are capable of differentiating to form spermatozoa morphologically characteristic of the donor species. Germ cell transplantation procedures combined with developments in freezing, culturing or enriching germ cell populations have applications of paramount importance in medicine, basic sciences and animal reproduction. Additionally, these techniques can serve as an alternative approach for gonadal protection and fertility preservation in patients with cancer. This article is a chronological critical review of the technological advances that followed the initial successful transplantation of mouse germ cells into recipient mice. Furthermore, the factors responsible for the immunological privilege properties of the testis and the parameters influencing the potential of mammalian germ cells to undergo mitosis and meiosis within a xenogeneic testis are described. Finally, the role of human germ cell transplantation procedures in the therapeutic management of non-obstructive azoospermia is discussed. 相似文献