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101.
Signal Transduction in Human T Lymphocytes 总被引:11,自引:0,他引:11
102.
Colman Seven D.; Collins Francis S.; Wallace Margaret R. 《Human molecular genetics》1993,2(10):1709-1711
The gene which is responsible for neurofibromatosis type 1 (NF1)is located on chromosome 17 (17q11.2). The NF1 gene is approximately350 kilobases (kb) long and exhibits an extremely high mutationrate; therefore, most patients are expected to have unique mutations.To date, relatively few mutations have been well characterized.We report here a de novo single base pair (bp) deletion in oneNF1 allele in a patient diagnosed with NF1 and leukemia. Wefurther characterized this mutation at the RNA level by allele-specificoligonucleotide (ASO) hybridization which demonstrated thatthe mutant allele is transcribed. 相似文献
103.
Synaptic transmission from cones is faster than transmission from rods. Using paired simultaneous recordings from photoreceptors and second-order neurones in the salamander retina, we studied the contributions of rod–cone differences in glutamate receptor properties and synaptic release rates to shaping postsynaptic responses. Depolarizing steps evoked sustained calcium currents in rods and cones that in turn produced transient excitatory postsynaptic currents (EPSCs) in horizontal and OFF bipolar cells. Cone-driven EPSCs rose and decayed faster than rod-driven EPSCs, even when comparing inputs from a rod and cone onto the same postsynaptic neurone. Thus, rod–cone differences in EPSCs reflect properties of individual rod and cone synapses. Experiments with selective AMPA and KA agonists and antagonists showed that rods and cones both contact pharmacologically similar AMPA receptors. Spontaneous miniature EPSCs (mEPSCs) exhibited unimodal distributions of amplitude and half-amplitude time width and there were no rod–cone differences in mEPSC properties. To examine how release kinetics shape the EPSC, we convolved mEPSC waveforms with empirically determined release rate functions for rods and cones. The predicted EPSC waveform closely matched the actual EPSC evoked by cones, supporting a quantal release model at the photoreceptor synapse. Convolution with the rod release function also produced a good match in rod-driven cells, although the actual EPSC was often somewhat slower than the predicted EPSC, a discrepancy partly explained by rod–rod coupling. Rod–cone differences in the rates of exocytosis are thus a major factor in producing faster cone-driven responses in second-order retinal neurones. 相似文献
104.
Dunckley H Dodd R Greville WD Hersee J Le T Taverniti A Wallace R Strickland J Hogbin JP Truong J Velickovic ZM 《Tissue antigens》2004,63(6):584-586
Anew human leukocyte antigen-B allele, B*1565, has been identified during routine typing of cord blood samples. Subsequently, two individuals from the same family as the first cord blood sample plus two unrelated Australian Bone Marrow Donor Registry samples have been found to carry this novel allele. 相似文献
105.
106.
Slavotinek A Poyser L Wallace A Martin F Gaunt L Kingston H 《American journal of medical genetics. Part A》2003,(3):282-288
We report two unusual patients with trisomy 18 mosaicism presenting with minor anomalies and failure to thrive in the first year of life. Chromosome analysis showed trisomy 18 in 30/30 peripheral blood lymphocytes in both children. Analysis of skin fibroblasts in the first child showed normal female chromosomes in 30/30 cells, and the fibroblast karyotype in the second child showed mosaicism for tetrasomy 18p, trisomy 18, and normal female chromosomes (karyotype 47,XX, +i(18)(p10)[47]/47,XX, +18[9] /46,XX[4]). Trisomy 18 commonly results from nondisjunction at maternal meiosis II (MII). Nondisjunction at maternal MII has also been postulated to be the initial step in the formation of tetrasomy 18p. In our second case, the additional chromosome 18 was the result of maternal nondisjunction at MII, consistent with this hypothesis. In the first case, nondisjunction at maternal meiosis I (MI) was responsible for the extra chromosome 18. 相似文献
107.
Dynamic imaging of the lungs using x-ray phase contrast 总被引:4,自引:0,他引:4
Lewis RA Yagi N Kitchen MJ Morgan MJ Paganin D Siu KK Pavlov K Williams I Uesugi K Wallace MJ Hall CJ Whitley J Hooper SB 《Physics in medicine and biology》2005,50(21):5031-5040
High quality real-time imaging of lungs in vivo presents considerable challenges. We demonstrate here that phase contrast x-ray imaging is capable of dynamically imaging the lungs. It retains many of the advantages of simple x-ray imaging, whilst also being able to map weakly absorbing soft tissues based on refractive index differences. Preliminary results reported herein show that this novel imaging technique can identify and locate airway liquid and allows lung aeration in newborn rabbit pups to be dynamically visualized. 相似文献
108.
The effect of celecoxib, a cyclooxygenase-2 inhibitor, in familial adenomatous polyposis 总被引:105,自引:0,他引:105
Steinbach G Lynch PM Phillips RK Wallace MH Hawk E Gordon GB Wakabayashi N Saunders B Shen Y Fujimura T Su LK Levin B Godio L Patterson S Rodriguez-Bigas MA Jester SL King KL Schumacher M Abbruzzese J DuBois RN Hittelman WN Zimmerman S Sherman JW Kelloff G 《The New England journal of medicine》2000,342(26):1946-1952
BACKGROUND: Patients with familial adenomatous polyposis have a nearly 100 percent risk of colorectal cancer. In this disease, the chemopreventive effects of nonsteroidal antiinflammatory drugs may be related to their inhibition of cyclooxygenase-2. METHODS: We studied the effect of celecoxib, a selective cyclooxygenase-2 inhibitor, on colorectal polyps in patients with familial adenomatous polyposis. In a double-blind, placebo-controlled study, we randomly assigned 77 patients to treatment with celecoxib (100 or 400 mg twice daily) or placebo for six months. Patients underwent endoscopy at the beginning and end of the study. We determined the number and size of polyps from photographs and videotapes; the response to treatment was expressed as the mean percent change from base line. RESULTS: At base line, the mean (+/-SD) number of polyps in focal areas where polyps were counted was 15.5+/-13.4 in the 15 patients assigned to placebo, 11.5+/-8.5 in the 32 patients assigned to 100 mg of celecoxib twice a day, and 12.3+/-8.2 in the 30 patients assigned to 400 mg of celecoxib twice a day (P=0.66 for the comparison among groups). After six months, the patients receiving 400 mg of celecoxib twice a day had a 28.0 percent reduction in the mean number of colorectal polyps (P=0.003 for the comparison with placebo) and a 30.7 percent reduction in the polyp burden (the sum of polyp diameters) (P=0.001), as compared with reductions of 4.5 and 4.9 percent, respectively, in the placebo group. The improvement in the extent of colorectal polyposis in the group receiving 400 mg twice a day was confirmed by a panel of endoscopists who reviewed the videotapes. The reductions in the group receiving 100 mg of celecoxib twice a day were 11.9 percent (P=0.33 for the comparison with placebo) and 14.6 percent (P=0.09), respectively. The incidence of adverse events was similar among the groups. CONCLUSIONS: In patients with familial adenomatous polyposis, six months of twice-daily treatment with 400 mg of celecoxib, a cyclooxygenase-2 inhibitor, leads to a significant reduction in the number of colorectal polyps. 相似文献
109.
J D Edinger W M Nelson K G Bailey J Wallace R Lyman 《Journal of clinical psychology》1979,35(4):807-814
Determined the efficacy of profile analysis with a prison population (63 white, 63 black) of the Petersburg Federal Correctional Institution as Ss. By use of Veldman's Hierarchical Profile Analysis, five distinctive WAIS profile types were derived empirically for each racial group. Analyses of covariance that controlled for full-scale IQ differences revealed significant differences among the profile types within each race in terms of Stanford Achievement Test scores and MMPI T-scores. Further, partial correlations indepepdent of full-scale IQ revealed significant relationships between some of the profile types and the commission of rule infractions while incarcerated. These findings are interpreted as supportive of profile analysis with inmate populations. However, it is suggested that further research be effected to cross-validate these findings. 相似文献
110.
Constitutional and mosaic large NF1 gene deletions in neurofibromatosis type 1. 总被引:7,自引:1,他引:7
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S A Rasmussen S D Colman V T Ho C R Abernathy P H Arn L Weiss C Schwartz R A Saul M R Wallace 《Journal of medical genetics》1998,35(6):468-471
A set of neurofibromatosis type 1 (NF1) patients was screened for large NF1 gene deletions by comparing patient and parent genotypes at 10 intragenic polymorphic loci. Of 67 patient/parent sets (47 new mutation patients and 20 familial cases), five (7.5%) showed loss of heterozygosity (LOH), indicative of NF1 gene deletion. These five patients did not have severe NF1 manifestations, mental retardation, or dysmorphic features, in contrast to previous reports of large NF1 deletions. All five deletions were de novo and occurred on the maternal chromosome. However, two patients showed partial LOH, consistent with somatic mosaicism for the deletion, suggesting that mosaicism may be more frequent in NF1 than previously recognised (and may have bearing on clinical severity). We suggest that large NF1 deletions (1) are not always associated with unusual clinical features, (2) tend to occur more frequently on maternal alleles, and (3) are an important mechanism for constitutional and somatic mutations in NF1 patients. 相似文献