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21.
180例慢性粒细胞白血病骨髓染色体畸变及意义 总被引:3,自引:0,他引:3
目的 研究骨髓染色体畸变与慢性粒细胞白血病 (慢粒 )不同病期的相关性及其临床意义。方法 采取新鲜骨髓 ,进行短期培养 (48小时或 12小时预加秋水仙素培养 )制备染色体标本 ,分析 180例慢粒患者慢性期、加速期、急变期骨髓染色体的变异情况。结果 180例慢粒患者 ,其中 16 4例Ph染色体阳性 (Ph ) ,占 91 1% ;16例Ph染色体阴性(Ph - ) ,占 8 9%。慢性期 133例Ph ,占总数的 73 9% ;加速期 9例Ph ,占总数 5 0 % ;急变期 2 2例Ph ,占总数12 2 %。 16 4例Ph 慢粒患者中 2 5例 (15 2 % )伴有额外染色体异常 ,其中慢性期占 4 2 7%、加速期占 2 4 %、急变期占8 5 3%。结果表明随着病情的进展 ,Ph 阳性率明显增高 ,其它染色体异常率也明显增高。结论 骨髓染色体畸变与慢粒白血病的病程进展、疾病预后有着十分重要的相关性 ,随着病情的演变 ,骨髓染色体畸变趋于复杂化。进行染色体分析对临床诊断及治疗慢粒具有十分重要的指导意义。 相似文献
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Karen G. Henderson Fred J. Dill Stephen Wood 《American journal of medical genetics. Part A》1992,44(5):615-618
A de novo chromosome aberration in a woman with severe mental retardation and minor anomalies has been characterized cytogenetically. The patient's karyotype was described as 46, XX, inv dup (8)(p12 → p23.1). Previous Southern blot dosage studies with the marker locus D8S7 demonstrated that the patient was monosomic for this locus, suggesting that the rearrangement generated a duplication-deficiency chromosome. We have reinvestigated this patient using fluorescent in situ hybridization with chromosome 8 cosmids and an Alu-PCR product specific for 8p. These studies have confirmed directly that the duplicated chromosome also has undergone deletion. © 1992 Wiley-Liss, Inc. 相似文献
24.
Prevalence of chromosomal abnormalities in 2078 infertile couples referred for assisted reproductive techniques 总被引:2,自引:0,他引:2
Clementini E Palka C Iezzi I Stuppia L Guanciali-Franchi P Tiboni GM 《Human reproduction (Oxford, England)》2005,20(2):437-442
BACKGROUND: This study analyses the prevalence of karyotype changes and Yq11 microdeletions among couples referred for assisted reproduction techniques. METHODS: Prior to receiving either IVF or ICSI treatment, each partner of 2078 infertile couples was screened for karyotype changes by GTG-banding technique on peripheral lymphocytes. No subject presented with obvious phenotype of chromosomal rearrangement. All the oligo/azoospermic men with normal karyotype were further investigated by PCR for Yq11 microdeletions. RESULTS: Eighty-two out of 2078 couples (3.95%) had one partner carrying a chromosomal change, and 10 out of 202 (4.95%) men showed Yq11 microdeletions. The chromosomal rearrangements were 44 (2.1%) translocations, 23 (1.1%) gonosomal mosaics, six (0.3%) 47,XXY, five (0.24%) marker chromosomes, three (0.14%) inversions and one (0.05%) duplication. Frequency of anomalies in men and women were similar: 42 and 40 cases respectively. CONCLUSIONS: Partners of infertile couples requiring IVF or ICSI treatment appear to be affected by higher frequency of chromosomal rearrangements than the general population. Categories with greater risk were represented by men with sperm cell count <20 x 10(6) sperm/ml, and women with history of pregnancy loss. 相似文献
25.
本文报告小儿遗传咨询门诊及新生儿科确诊的遗传病:染色体病23例,其中核型异常16例,结构异常7例;常染色体显性遗传病11例,常染色体隐性遗传病28例;性连锁遗传病6例;血红蛋白异常1例,共计69例。常染色体遗传病占55%,染色体异常综合征占33%。常染色体病种类繁多,尽管发病率不高,但危害很大,给诊断带来困难。 相似文献
26.
Chromosomal factors of infertility in candidate couples for ICSI: an equal risk of constitutional aberrations in women and men 总被引:8,自引:0,他引:8
Gekas J Thepot F Turleau C Siffroi JP Dadoune JP Briault S Rio M Bourouillou G Carré-Pigeon F Wasels R Benzacken B;Association des Cytogeneticiens de Langue Francaise 《Human reproduction (Oxford, England)》2001,16(1):82-90
To assess the frequency of chromosomal aberrations in French candidates for intracytoplasmic sperm injection (ICSI), and to explore the existence of a female chromosomal factor in some cases of couple infertility, a collaborative retrospective clinical and cytogenetic study was performed, launched by the Association des Cytogénéticiens de Langue Franciaise (ACLF). The karyotypes of 3208 patients [2196 men (68.4%), 1012 (31.6%) women] included in ICSI programmes over a 3-year period in France were collected. A total of 183 aberrant karyotypes was diagnosed, corresponding to an abnormality frequency of 6.1% (134/2196) for men and 4.84% (49/1012) for women. The following frequencies of abnormalities were observed respectively for men and women: 1.23% (n = 27) and 0.69% (n = 7) for reciprocal translocations, 0.82% (n = 18) and 0.69% (n = 7) for Robertsonian translocations, 0.13% (n = 3) and 0.69% (n = 7) for inversions, 3.32% (n = 73) and 2.77% (n = 28) for numerical sex chromosome aberrations, and 0.59% (n = 13) and 0% for other structural aberrations. Among the male patients of this latter group, 0.40% (n = 9) had a Y chromosome abnormality. Among the male patients with numerical sex chromosome abnormalities, 2.23% (n = 49) were 47,XXY, 0.32% (n = 7) were 47,XYY, and 0.77% (n = 17) had a mosaicism for numerical sex chromosome anomalies. All the female patients with sex chromosome abnormalities (2.77%, n = 28) had mosaicism for numerical sex chromosome anomalies. Even if these cases-the significance of which was sometimes questioned-were disregarded in the analysis, 2.08% (21/1012) of abnormal karyotypes remained in women. An overall increased frequency of chromosomal aberrations was found, and this confirmed that in some cases of poor reproductive outcome there may be a contribution of maternal chromosome aberrations. Indeed, the existence of a chromosome abnormality in the female partner was associated with the group of infertile men in which there was no apparent cause of infertility. 相似文献
27.
Summary The gene FUR4, coding for the uracil permease in Saccharomyces cerevisiae, was mapped on chromosome II, at a distance of 7.8 cM from the centromere on the right arm of the chromosome. In a first step, we used the chromosome loss mapping method developed by Falco and Botstein (1983) to determine on which chromosome the gene mapped. After the observation that FUR4 was closely linked to GAL10, one of the three genes forming the gal cluster (Bassel and Mortimer 1971), we could determine precisely the position of the gene on chromosome II. 相似文献
28.
The insecticides demeton, dimetoat, dichlorovos, endosulfan, trichlorofon, carbaryl, lindane, methoxychlor, propoxur and malathion were examined for their ability to induce chromosomal aberrations in the bone marrow cells of the Syrian hamster (Mesocricetus auratus) treated in vivo. Mutagenicity of commercial preparations was examined at four doses: LD50; 1/2, 1/5 and 1/10 LD50. The positive control was an IP injection of cyclophosphamide to hamsters at a dose of 40 mg/kg body wt. Demeton, dichlorovos and endosulfan gave positive results. Malathion, dimethoate and the mixture of methoxychlor and propoxur were weakly clastogenic; at some doses these compounds induced statistically significant increases in the number of aberrations. Trichlorfon and the mixture of carbaryl and lindane were negative in this test.This work was supported by the Polish Academy of Sciences within the projet 09.7.3.4.3 相似文献
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30.
快杀灵对小鼠骨髓细胞的细胞毒性和遗传毒性检测 总被引:3,自引:2,他引:1
目的检测快杀灵是否具有细胞毒性和诱变性.方法按受试药物LD50的1/4×、1/2×、1×和2×四种不同剂量,分5次(间隔24小时)经口灌胃给小鼠染毒,然后用细胞遗传学方法,检测骨髓细胞的有丝分裂指数、染色体结构畸变率和畸变细胞率的变化.结果与阴性对照组比较,18.2mg/kg的剂量就使骨髓细胞的有丝分裂指数显著降低(P<0.001).18.2mg/kg和36.4mg/kg剂量组的染色体结构畸变率和畸变细胞率有增高,但无显著性差异(P>0.05),72.8mg/kg和145.6mg/kg剂量组的染色体结构畸变率和畸变细胞率均有显著增高(P<0.01).结论快杀灵既可抑制细胞增殖,又可诱发染色体损伤.快杀灵对细胞增殖的抑制作用比对染色体的损伤作用更加强烈. 相似文献