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51.
目的运用全染色体探针荧光原位杂交技术(fluorescent in situ hybridization ,FISH)对14/21罗伯逊易位携带者的胚胎进行植入前遗传学诊断,达到优生目的.方法应用FITC、Texas标记的21/14全染色体探针对14/21罗伯逊易位携带者的胚胎活检后的单个卵裂球进行遗传学检测,选择正常信号或携带者信号核型胚胎进行移植.结果常规单精子显微注射-胚胎移植(intracytoplasmic sperm injection,ICSI)后获取胚胎12个,活检优质胚胎11个,杂交后有信号胚胎7个,其中1个正常胚胎,1个携带者胚胎;1个14单体胚胎,1个21单体胚胎,1个21三体胚胎,另2个胚胎活检后均为21号二体,无14号信号.结论运用14/21全染色体探针荧光原位杂交技术对14/21罗伯逊易位携带者的胚胎进行植入前遗传学诊断是能够将正常核型胚胎挑选出来进行移植,从而达到优生目的. 相似文献
52.
Fibre optic confocal imaging (FOCI) of keratinocytes, blood vessels and nerves in hairless mouse skin in vivo 总被引:1,自引:0,他引:1
L. J. BUSSAU L. T. VO P. M. DELANEY G. D. PAPWORTH D. H. BARKLA R. G. KING 《Journal of anatomy》1998,192(2):187-194
Fibre optic confocal imaging (FOCI) enabled subsurface fluorescence microscopy of the skin of hairless mice in vivo. Application of acridine orange enabled imaging of the layers of the epidermis. The corneocytes of the stratum corneum, the keratinocytes in the basal layers and redundant hair follicles were visualised at depths greater than 100 μm. Cellular and nuclear membranes of keratinocytes of the skin were visualised by the use of acridine orange and DIOC5(3). Imaging of the skin after injection of FITC-dextran revealed an extensive network of blood vessels with a size range up to 20 μm. Blood cells could be seen moving through dermal vessels and the blood circulation through the dermal vascular bed was video-taped. The fluorescent dye 4-di-2-ASP showed the presence of nerves fibres around the hair follicles and subsurface blood vessels. Comparison was made between images obtained in vivo using FOCI and in vitro scanning electron microscopy and conventional histology. FOCI offers the potential to study dynamic events in vivo, such as blood flow, skin growth, nerve regeneration and many pathological processes, in ways which have not previously been possible. 相似文献
53.
目的:选择能与整合素α3受体结合的小分子多肽cNGQGEQc-L作为靶向载体,将羧基荧光素(FAM)与cNGQGEQc-L连接构建荧光分子探针,通过荧光成像探讨荧光多肽分子探针用于肺腺癌显像的可行性。方法:利用倒置荧光显微镜观察FAM-cNGQGEQc-L与肺腺癌A549细胞结合部位,流式细胞仪检测荧光多肽与A549细胞的竞争抑制实验,观察FAM-cNGQGEQc-L随浓度的增加与肺腺癌A549细胞结合能力的变化情况。通过小动物活体成像仪,观察荧光多肽在荷瘤裸鼠体内的生物分布特点。结果:倒置荧光显微镜显示荧光多肽cNGQGEQc-L能与A549细胞结合,结合部位在细胞膜和细胞质中。流式细胞仪测试结果证明荧光多肽与A549细胞的结合具有特异性和饱和性,当FAM-cNGQGEQc-L浓度为0.125 mmol/L时,荧光多肽与A549细胞的结合趋近饱和。荷瘤裸鼠活体成像显示移植瘤能够摄取荧光多肽,且荧光多肽通过泌尿系统和胆道系统排泄。结论:体外、体内荧光实验结果显示,荧光多肽分子探针FAM-cNGQGEQc-L可与肺腺癌A549细胞、肺癌移植瘤结合,能够特异性靶向肺腺癌。 相似文献
54.
Yamamoto N Yang M Jiang P Xu M Tsuchiya H Tomita K Moossa AR Hoffman RM 《Clinical & experimental metastasis》2003,20(7):633-638
We have established stable, bright green fluorescent protein (GFP)- or red fluorescent protein (RFP)-expressing HT-1080 human
fibrosarcoma clones. These cell lines showed similar cell proliferation rates and high-frequency experimental lung metastasis.
The HT-1080-GFP and -RFP clones enable simultaneous real-time dual-color imaging in the live animal. HT-1080 cells were transduced
with retroviral vectors containing GFP or RFP and the neomycin resistance gene. Stable transformants were selected stepwise
with G418 up to 800 μl/ml. Subsequently, high GFP- or RFP-expressing clones, HT-1080-GFP or HT-1080-RFP, respectively, were
selected. 3×106 cells from each clone were mixed and injected into the tail vein of SCID mice. The cells seeded the lung at high frequency
with subsequent formation of pure green and pure red colonies as well as mixed yellow colonies with different patterns visualized
directly on excised lungs. The lung metastases were also visualized by external fluorescence imaging in live animals through
skin-flap windows over the chest wall. Lung metastases were observed on the lung surface of all mice. SCID mice well tolerated
multiple surgical procedures for direct-view imaging via skin-flap windows. Real-time metastatic growth of the two different
colored clones in the same lung was externally imaged with resolution and quantification of green, red, or yellow colonies
in live animals. The color coding enabled determination of whether the colonies grew clonally or were seeded as a mixture
with one cell type eventually dominating, or whether the colonies grew as a mixture. The simultaneous real-time dual-color
imaging of metastatic colonies described in this report gives rise to the possibility of color-coded imaging of clones of
cancer cells carrying various forms of gene of interest.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
55.
Cell culture-based transdominant genetic techniques provide new methods for discovering peptide/RNA modulators of cellular pathways. We applied this technology to isolate a peptide inhibitor of human rhinovirus. A green fluorescent protein (GFP)-scaffolded library of cDNA fragments was expressed in HeLa cells from a retroviral vector and screened for inhibitors of rhinovirus-mediated cell killing. A DNA clone, I421, increased cell survival in an HRV14 challenge assay from less than 0.5% to greater than 60%. It encodes a 53-amino-acid C-terminal extension of the GFP scaffold. Particular subclones of Hela cells expressing I421 (exemplified by I421dp3) show a delay in virus production and a 50-fold decrease in viral RNA levels at 6-8 h postinfection. HRV2, HRV14, and HRV16 show a dramatic decrease in plaque-forming ability on I421dp3 while Coxsackievirus B3 showed a small reduction. Levels of ICAM-1, the receptor for the main rhinovirus serotype, are not altered in I421dp3. 相似文献
56.
Highly repetitive DNA sequences were isolated from genomic DNA libraries of Alstroemeria psittacina and A. inodora. Among the repetitive sequences that were isolated, tandem repeats as well as dispersed repeats could be discerned. The tandem
repeats belonged to a family of interlinked Sau3A subfragments with sizes varying from 68–127 bp, and constituted a larger HinfI repeat of approximately 400 bp. Southern hybridization showed a similar molecular organization of the tandem repeats in
each of the Brazilian Alstroemeria species tested. None of the repeats hybridized with DNA from Chilean Alstroemeria species, which indicates that they are specific for the Brazilian species. In-situ localization studies revealed the tandem repeats to be localized in clusters on the chromosomes of A. inodora and A. psittacina: distal hybridization sites were found on chromosome arms 2PS, 6PL, 7PS, 7PL and 8PL, interstitial sites on chromosome arms
2PL, 3PL, 4PL and 5PL. The applicability of the tandem repeats for cytogenetic analysis of interspecific hybrids and their
role in heterochromatin organization are discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
57.
New HLA-A*11 allele,A*1112, identified by sequence-based typing 总被引:1,自引:0,他引:1
Garino E Belvedere M Berrino M Bertola L Dall'Omo AM Mazzola G Rossetto C Carcassi C Lai S Gay E Ricotti M Curtoni ES 《Tissue antigens》2002,60(1):84-87
In this report, we describe the identification of HLA-A*1112, a novel HLA-A*11 allele found in two Italian families. The new allele was detected during routine HLA typing by a polymerase chain reaction sequence-specific primer and was confirmed by high-resolution sequencing-based typing. The nucleotide sequences of HLA-A*1112 exons 2 and 3 are identical to HLA-A*11011 except for a single nucleotide substitution in codon 90 (GAC-->GCC). 相似文献
58.
I. A. Leneva P. V. Gulak Yu. N. Dubrov A. S. Sobolev 《Bulletin of experimental biology and medicine》1990,109(5):641-644
Department of Biomembranes, Research Center for Development and Introduction of Modern Methods of Molecular Diagnosis, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR I. P. Ashmarin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 109, No. 5, pp. 483–485, May, 1990. 相似文献
59.
C. A. Verburgh H. G. J. M. Kuypers 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,68(3):565-578
Summary Branching neurons giving rise to ascending and descending collaterals were studied in the cervical spinal cord of the rat. After unilateral injection of two retrograde fluorescent tracers, i.e. DY.2HCl at T2 or more caudal levels and TB at C1 or more rostral levels, many DY-TB double-labeled neurons were found in C3 to C8. These neurons were located bilaterally throughout the spinal grey matter, as well as in the lateral spinal nucleus (LSN). However, no double-labeled neurons could be detected in the laminae I and II on either side. The double-labeled neurons must represent branching neurons giving rise to a collateral ascending to the rostral injection-site or above, and another collateral descending to the caudal injection-site or below. The descending collaterals were found to extend to various spinal levels, including the lumbosacral cord. However, most of them terminated at shorter distances from their parent cell bodies; thus 20% of the C3–C8 neurons projecting to C1 or above had a descending collateral reaching T2, 8% had a collateral reaching T9, and 3% a collateral reaching L2/L3. The ascending collaterals of the majority of the branching neurons passed into the most caudal part of the medulla oblongata, and about half of these collaterals reached the level of the rostral part of the inferior olive. In regard to the neurons located in the segments C5–C8, about 13% of those projecting to T2 or below distribute an ascending collateral restricted to C2–C4, while 29% of those had an ascending collateral to C1 or above. 相似文献
60.