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991.
992.
Chromosome specific comparative genome hybridisation for determining the origin of intrachromosomal duplications. 总被引:1,自引:0,他引:1 下载免费PDF全文
D K Griffin D Sanoudou E Adamski C McGiffert P O''Brien J Wienberg M A Ferguson-Smith 《Journal of medical genetics》1998,35(1):37-41
Chromosome specific comparative genome hybridisation (CGH) is a novel approach for the detection of cytogenetic abnormalities. It combines flow sorting of chromosomes, degenerate oligonucleotide primed (DOP)-PCR and a modified comparative genome hybridisation (CGH) technique to define the site and extent of intrachromosomal duplications. Chromosome specific paint probes for aberrant chromosomes and their normal homologues from four subjects with unbalanced duplications within chromosomes 2p11-15, 3q25-26, 5q34-qter, and 12q23-24.2 were made. They were then cohybridised on normal metaphase spreads and the ratio of their relative intensities of hybridisation analysed. The results were compared to those of similar experiments where regular CGH was performed on the same four patients. We provide evidence that this method can detect duplications and deficiencies which might be missed by conventional CGH, as the ratio of hybridisation of abnormal/normal DNA is 2:1 rather than 3:2. It is the method of choice where mosaicism is present or where only one of several homologous chromosomes is duplicated. Furthermore, it suggests that DOP-PCR amplifies all or most of the euchromatic regions of the genome equally. 相似文献
993.
994.
SM Williams R Scragg EA Mitchell BJ Taylor 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(11):1284-1289
Objective : To compare the growth curves based on measurements of body weight for male and female infants dying of sudden infant death syndrome (SIDS) with those of male and female controls. Methods : The data were drawn from a large case control study of SIDS carried out in New Zealand between 1987 and 1990. Results : The mean birthweight for the cases was 3049 g and for the controls 3526 g. The mean growth curves for the male and female controls were close to the 50th centile of growth charts used in New Zealand. The growth curve for the male cases diverged from that of the controls, being closer to the 25th percentile. The differences between the female cases and controls were less pronounced. The differences in weekly weight increments derived from the curves for the cases and controls for nine 4-week periods were not statistically significant after taking into account race, manner of feeding and maternal smoking for any 4-week period. Conclusions : SIDS cases were lighter at birth, but their growth velocity was normal postnatally. 相似文献
995.
996.
Long-term outcomes of radiologically placed arm ports 总被引:2,自引:0,他引:2
997.
Manasco PK; Umbach DM; Muly SM; Godwin DC; Negro-Vilar A; Culler MD; Underwood LE 《Human reproduction (Oxford, England)》1997,12(10):2108-2114
We measured luteinizing hormone (LH) and follicle stimulating hormone (FSH)
by immunofluorometric assays and alpha-inhibin by radioimmunoassay in serum
sampled every 10 min throughout the night (2100-0500 h) from 44 normal
girls. Mean overnight LH values rose log- linearly from a mean of 0.2 IU/l
in prepubertal girls to 3.0 IU/l in late pubertal girls. Log2 mean
overnight FSH rose rapidly through early puberty and then remained
constant; mean FSH rose from 1.0 IU/l in prepubertal girls to approximately
2.8 IU/l in Tanner III-V girls. Mean overnight inhibin increased through
puberty, rising from 151 ng/l in prepubertal girls to 432 ng/l in fully
pubescent girls. Within each of the first three Tanner stages, LH differed
approximately 100-fold between the smallest and largest mean concentrations
but differed <10- fold within stages IV or V. Such within-pubertal stage
variability was less pronounced for FSH, which differed approximately
16-fold among Tanner I subjects and 4-10-fold at later stages, and for
inhibin, which varied approximately 4-fold within each Tanner stage. The
frequency of LH pulses during overnight sampling increased significantly
during puberty, but the frequency of FSH and inhibin pulses remained
constant. We compared the results from girls to those from 50 normal boys
[Manasco et al. (1995) J. Clin. Endocrinol. Metab., 80, 20462052]. At each
pubertal stage, girls had approximately the same mean overnight LH values
as boys; girls had higher mean overnight FSH, particularly during Tanner
stages II-IV; and boys had mean overnight alpha-inhibin immunoreactivity
approximately 1.5 times that of girls at each pubertal stage. Still,
hormone concentrations for individuals of both sexes intergraded at each
pubertal stage.
相似文献
998.
M. T. Walsh E. G. Kavanagh T. O''Brien P. A. Grace T. McGloughlin 《European journal of vascular and endovascular surgery》2003,26(6):649-656
BACKGROUND: To investigate hemodynamic flow changes associated with vein cuffs and patches that may be responsible for improved patency of prosthetic infrainguinal grafts. METHODS: The role of the graft-artery junction angle was examined by computational fluid dynamics to assess the influence of anastomotic geometry on wall shear stress (WSS) distributions. Three geometrically different junction configurations were studied and the WSS and WSS gradient (WSSG) values were compared. RESULTS: The inclusion of a patch or a cuff moves the bed stagnation point (BSP) distally, increasing the area on the bed of the junction which experiences a BSP and reducing the strength of the recirculation region opposite the heel of the junction by 54.8 and 50.8%, respectively. The patched geometry promotes earlier recovery of the flow in the distal outflow segment (DOS) than for the unpatched model. Also, the helical flow patterns in the DOS associated with the cuffed geometry are stronger. The net effect of these changes are that peak WSSG values for the patched and cuffed geometries are three times lower than those for the uncuffed geometry. CONCLUSION: This study provides some additional insights into the hemodynamics of graft-artery junction geometry which may influence future clinical practice. 相似文献
999.
1000.
Airway hyperreactivity: assessment with helical thin-section CT 总被引:1,自引:0,他引:1