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101.
Supernumerary marker chromosomes (SMC) can be associated with both normal and abnormal phenotypes. In addition, SMC are found at higher frequency in males with infertility. We identified a SMC, characterized as a del(15)(q11.2) chromosome, in a phenotypically normal male. Using fluorescence in situ hybridization (FISH), we examined the segregation of the del(15) chromosome in sperm from this patient. Only 6.23% of sperm nuclei showed disomy using a chromosome 15 alpha-satellite FISH probe, instead of the expected 50%. In addition, FISH analysis showed no increase for non-disjunction of chromosome 18, excluding an interchromosomal effect for this chromosome. The significant decrease in sperm bearing the del(15) may be due to tissue-specific mosaicism or a result of some form of selection against the del(15) during spermatogenesis. This finding provides a basis for the observation that SMC(15) are less likely to be inherited from a paternal carrier. 相似文献
102.
目的 建立荧光定量PCR技术检测 2 1三体综合征。方法 采用PCR方法同时扩增位于 2 1号染色体上的人肝型磷酸果糖激酶基因 (humanliver typephosphofructokinasegene ,PFKL CH 2 1)和位于 1号染色体上的人肌型磷酸果糖激酶基因 (humanmuscle typephosphofructokinasegene ,PFKM CH1) ,使用SYBRGreenⅠ荧光染料处理产物、琼脂糖电泳后在凝胶成像系统进行分析 ,得出扩增产物的荧光强度对比值。用此方法检测 2 6例 2 1三体综合征患儿及 2 0名正常人。结果 2 6例 2 1三体综合征患儿PFKL CH2 1/PFKM CH 1扩增产物的荧光强度对比值为 1.5 8± 0 .17,而正常人为 1 0 0± 0 .0 5 ,两者差异有显著性。结论 SYBRGreenⅠ荧光定量PCR技术检测 2 1三体综合征具有准确、快速、安全、实用等特点 ,有较高的临床使用价值。 相似文献
103.
104.
Portero P Bigard AX Gamet D Flageat JR Guézennec CY 《European journal of applied physiology》2001,84(6):540-546
The purpose of this study was to quantify the neuromuscular cervical adaptations to an 8 week strength training programme.
Seven healthy men, with no pathological conditions of the neck, performed a lateral flexion isometric resistance-training
programme three times a week. The training sessions consisted of one set of ten contractions, each of 6 s duration, at 60%
of the predetermined maximal voluntary isometric torque (MVTim) (warm-up) and two sets of eight contractions, each of 6 s duration, at 80% MVTim. The training effects were evaluated in three ways: muscle size, strength and fatigability. The cross-sectional areas (CSA)
of the trapezius (TRP) and sternocleidomastoideus (SCM) muscles were determined using a computerised tomographic scanner.
Results showed an increase in the CSA of TRP and SCM muscles after training, 8.8% at C5 level and 6.4% at C7 level for SCM
muscle and 12.2% at C7 level for TRP muscle. Strength increased significantly under both isometric and isokinetic conditions
(35% and 20%, respectively). Muscle fatigability in lateral flexion was quantified during a sustained isometric contraction
at 50% of MVTim. The shift of the mean power frequency of the electromyogram power spectrum density function of SCM muscle toward lower frequencies
was less after training (14.6% compared to 6.8%). These results indicate the beneficial effect of a strength-training programme
which increases neck muscle size and strength during lateral flexion, and decreases the fatigability of the superficial muscles
of the neck.
Electronic Publication 相似文献
105.
H Van Dekken E W Schervish J G Pizzolo W R Fair M R Melamed 《The Journal of pathology》1991,164(1):17-22
We have used fluorescent in situ hybridization and simultaneous in vivo bromodeoxyuridine labelling of a solid bladder cancer to examine tumour cell subsets for possible proliferative growth differences. In this dual-labelled preparation, most tumour cell nuclei exhibited monosomy 9, consistent with reported karyotypes of bladder cancer. Incorporated bromodeoxyuridine was visualized with a fluoresceinated antibody in 5-6 per cent of the tumour cells, concordant with S-phase estimates by cell cycle analysis of the flow cytometric DNA histogram. A majority of the bromodeoxyuridine-positive cells also carried the monosomy 9 chromosome abnormality. This is the first report to demonstrate the feasibility of combined in situ hybridization and detection of bromodeoxyuridine incorporated in vivo in human tumour cells in order to provide information on the growth rate of specific subsets of tumour cells identified by chromosomal constitution. 相似文献
106.
目的 分析眼附属器淋巴组织增生性病变的临床病理特点,探讨其分子遗传学特征及其意义.方法 收集1995-2007年37例眼附属器淋巴组织增生性病变石蜡组织标本(其中5例为反应性增生性病变,32例为淋巴瘤),依据2001年WHO肿瘤分类标准对32例淋巴瘤标本重新诊断分类.采用IgH、MALT1、bcl-6、c-Mye、bcl-2、CCND1、bcl-10、FOXP1双色分离重排探针、IgH/bcl-2双色融合易位探针和18号染色体着丝粒探针,利用间期荧光原位杂交(FISH)的方法 检测眼附属器淋巴组织增生性病变的分子遗传学特点.结果 32例淋巴瘤均为非霍奇金B细胞淋巴瘤.其中,黏膜相关淋巴组织结外边缘区B细胞淋巴瘤(MALT)淋巴瘤28例(87.5%),滤泡性淋巴瘤2例,弥漫性大B细胞淋巴瘤2例.60.7%(17/28)的眼附属器MALT淋巴瘤携带分子遗传学异常.其中,IgH基因断裂1例,但未找到与其发生相互易位的伙伴基因;基因3拷贝者16例,其中MALT1基因、bcl-6基因和c-Myc基因3拷贝的发生率分别为25%(7/28)、43%(12/28)和7%(2/28).16例基因3拷贝病例中,两种基因3拷贝合并存在者5例,其中bcl-6基因合并MALT1基因3拷贝者4例,bcl-6基因合并c-Myc基因3拷贝者1例.进一步研究显示,MALT1基因3拷贝者均存在18号染色体三体.2例滤泡性淋巴瘤都携带t(14;18)(q32;q21)/IgH-bcl-2.2例弥漫性大B细胞淋巴瘤均存在遗传学异常,1例表现为bcl-6基因3拷贝合并18号染色体三体,另1例表现为bcl-6基因3拷贝合并IgH和c-Myc基因双断裂.5例反应性淋巴组织增牛性标本均未见分子遗传学异常.结论 MALT淋巴瘤是眼附属器最常见的淋巴瘤类型;间期FISH有助于淋巴组织增生性病变的良恶性鉴别及淋巴瘤的分类;MALTI基因3拷贝者由18号染色体三体所致;18号染色体三体和bcl-6基因3拷贝(可能为3号染色体三体所致)是眼附属器MALT淋巴瘤常见的分子遗传学异常. 相似文献
107.
Development of flow cytogenetics and physical genome mapping in chickpea (Cicer arietinum L.) 总被引:2,自引:0,他引:2
K. Vláčilová D. Ohri J. Vrána J. Číhalíková M. Kubaláková G. Kahl J. Doležel 《Chromosome research》2002,10(8):695-706
Procedures for flow cytometric analysis and sorting of mitotic chromosomes (flow cytogenetics) have been developed for chickpea (Cicer arietinum). Suspensions of intact chromosomes were prepared from root tips treated to achieve a high degree of metaphase synchrony. The optimal protocol consisted of a treatment of roots with 2mmol/L hydroxyurea for 18h, a 4.5-h recovery in hydroxyurea-free medium, 2h incubation with 10µmol/L oryzalin, and ice-water treatment overnight. This procedure resulted in an average metaphase index of 47%. Synchronized root tips were fixed in 2% formaldehyde for 20min, and chromosome suspensions prepared by mechanical homogenization of fixed root tips. More than 4×105 morphologically intact chromosomes could be isolated from 15 root tips. Flow cytometric analysis of DAPI-stained chromosomes resulted in histograms of relative fluorescence intensity (flow karyotypes) containing eight peaks, representing individual chromosomes and/or groups of chromosomes with a similar relative DNA content. Five peaks could be assigned to individual chromosomes (A, B, C, G, H). The purity of sorted chromosome fractions was high, and chromosomes B and H could be sorted with 100% purity. PCR on flow-sorted chromosome fractions with primers for sequence-tagged microsatellite site (STMS) markers permitted assignment of the genetic linkage group LG8 to the smallest chickpea chromosome H. This study extends the number of legume species for which flow cytogenetics is available, and demonstrates the potential of flow cytogenetics for genome mapping in chickpea. 相似文献
108.
Henrik Aggerbeck Bent Nørgaard-Pedersen Iver Heron 《Journal of immunological methods》1996,190(2):171-183
A dual, double antigen, time-resolved fluorescence immunoassay (DELFIA) for the simultaneous detection and quantitation of diphtheria (D) and tetanus (T) antibodies in sera has been developed. In the double antigen format one arm of the antibody binds to antigen coated microtitre wells and the other arm binds to labelled antigen to provide a fluorescent signal. This assay was found to be functionally specific for IgG antibodies and showed a good correlation with established toxin neutralization assays. Furthermore, the double antigen set-up was species independent, permitting the direct use of existing international references of animal origin to measure protective antibody levels in humans in international units (IU/ml). The detection limit corresponded to 0.0003 IU/ml with Eu3+-labelled toxoids and to 0.0035 IU/ml using Sm3+-labelled toxoids. The assay was fast with a high capacity making it a suitable method for serological surveillance studies. 相似文献
109.
对心脑疾病人群的同步十二导联ECG(心电图)进行多重分形特性分析,发现不同导联的多重分形曲线互不重叠。计算其十二导联平均的多重分形奇异强度分布范围以及分布范围的十二个导联间的离散特性,发现不同人群中存在互为交叉而有明显不同的结果。用十二导联多重分形Δα的平均值Δα及其离散度δα(取Δα的标准差)两个参量来描述其多重分形谱特征。发现健康人与心脏病人Δα接近,但δα相差较大;健康人与脑损伤患者δα接近,但Δα相差较大。预示着多重分形特性受到神经自律和心脏组织结构的自谐特性的双重控制,特征参数Δα与神经控制相对应,δΔ与心脏组织结构自谐特性的各向异性相对应。 相似文献
110.
Lyudmila?Solov’eva Maria?Svetlova Dawn?Bodinski Andrei?O.?ZalenskyEmail author 《Chromosome research》2004,12(8):817-823
Specific and well-organized chromosome architecture in human sperm cells is supported by the prominent interactions between
centromeres and between telomeres. The telomere-telomere interactions result in telomere dimers that are positioned at the
nuclear periphery. It is unknown whether composition of sperm telomere dimers is random or specific. We now report that telomere
dimers result from specific interactions between the two ends of each chromosome. FISH using pairs of subtelomeric DNA probes
that correspond to the small and long arms of seven human chromosomes demonstrates that subtelomeres of one chromosome are
brought together. Statistical analysis confirmed that telomere associations could not result from the random proximity of
DNA sequences. Therefore, chromosomes in human sperm nuclei adopt a looped conformation. This higher-order chromosome structure
is most likely required for chromosome withdrawal/decondensation during the early fertilization events leading to zygote formation.
These individuals contributed equally to the work 相似文献