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91.
The genes encoding the peripheral cannabinoid receptor and alpha-L-fucosidase are located near a newly identified common virus integration site, Evi11. 总被引:2,自引:0,他引:2 下载免费PDF全文
P J Valk S Hol Y Vankan J N Ihle D Askew N A Jenkins D J Gilbert N G Copeland N J de Both B Lwenberg R Delwel 《Journal of virology》1997,71(9):6796-6804
A new common region of virus integration, Evi11, has been identified in two retrovirally induced murine myeloid leukemia cell lines, NFS107 and NFS78. By interspecific backcross analysis, it was shown that Evi11 is located at the distal end of mouse chromosome 4, in a region that shows homology with human 1p36. The genes encoding the peripheral cannabinoid receptor (Cnr2) and alpha-L-fucosidase (Fuca1) were identified near the integration site by using a novel exon trapping system. Cnr2 is suggested to be the target gene for viral interference in Evi11, since proviruses are integrated in the first intron of Cnr2 and retroviral integrations alter mRNA expression of Cnr2 in NFS107 and NFS78. In addition, proviral integrations were demonstrated within the 3' untranslated region of Cnr2 in five independent newly derived CasBrM-MuLV (mouse murine leukemia virus) tumors, CSL13, CSL14, CSL16, CSL27, and CSL97. The Cnr2 gene encodes a seven-transmembrane G-protein-coupled receptor which is normally expressed in hematopoietic tissues. Our data suggest that the peripheral cannabinoid receptor gene might be involved in leukemogenesis as a result of aberrant expression of Cnr2 due to retroviral integration in Evi11. 相似文献
92.
We examined substrate use by a group of white-faced capuchins (Cebus capucinus) during the dry season in the seasonally dry
forest at Palo Verde National Park, Costa Rica. The group's most common terrestrial activities were foraging and traveling.
Subjuveniles were most terrestrial, traveling terrestrially 55% of the time and foraging terrestrially 42% of the time. Juveniles
were least terrestrial (36% travel, 24% forage). Rest and social activity were highly arboreal for all age classes. Terrestrial
foraging was most common in the middle of the day. Terrestrial traveling became increasingly common over the course of the
day. 相似文献
93.
94.
R. E. Gilbert M. R. Stanford H. Jackson R. E. Holliman M. D. Sanders 《BMJ (Clinical research ed.)》1995,310(6986):1037-1040
OBJECTIVE--To determine the incidence of acute symptomatic toxoplasma retinochoroiditis presenting to ophthalmologists for patients born in Britain and elsewhere. DESIGN--Population based, cross sectional study. SETTING--11 districts in south Greater London. SUBJECTS--All patients presenting to NHS ophthalmologists with symptoms due to acute toxoplasma retinochoroiditis in 1992-3. MAIN OUTCOME MEASURE--Intraocular inflammation in association with a retinochoroidal scar, active adjoining retinitis, and IgG serum antibodies to toxoplasma. RESULTS--The estimated incidence of acute symptomatic retinochoroiditis for all people born in Britain was 0.4/100,000/year. If a mean of two symptomatic episodes per lifetime is assumed, 100 people born in Britain may be affected each year, about a fifth of the estimated 500-600 congenitally infected people born each year. CONCLUSIONS--A substantial proportion of people with acute symptomatic toxoplasma retinochoroiditis were born outside the country, and the number born in Britain was smaller than the number previously estimated to develop retinochoroidal lesions due to congenital toxoplasmosis. These findings suggest that prenatal screening for toxoplasmosis in Britain may be of limited benefit. 相似文献
95.
R. E. Gilbert R. E. Wigfield P. J. Fleming P. J. Berry P. T. Rudd 《BMJ (Clinical research ed.)》1995,310(6972):88-90
OBJECTIVE--To determine whether the risk of the sudden infant death syndrome is increased in bottle fed babies. DESIGN--Population based case-control study matching for age and time. SUBJECTS--All babies aged 1 week to 1 year dying of sudden infant death syndrome during November 1987 to April 1989 or February 1990 to June 1991 and two live controls. SETTING--Avon and north Somerset. MAIN OUTCOME MEASURES--Breast or bottle feeding, sleeping position, maternal smoking, parental employment, and length of gestation. RESULTS--Compared with being fully breast fed, the crude odds ratio for sudden infant death in fully bottle fed babies was 3.1 and for mixed breast and bottle fed babies 1.5. These odds ratios fell to 1.8 (95% confidence interval 0.7 to 4.8) and 1.2 (0.5 to 2.7) respectively after maternal smoking, parental employment, preterm gestation, and sleeping position had been adjusted for. Sleeping position partly masked the effect of being bottle fed on sudden infant death as breast fed babies were more likely to have slept prone than bottle fed babies. CONCLUSIONS--Bottle feeding is not a significant independent risk factor for the sudden infant death syndrome. Patterns of maternal smoking, preterm gestation, and parental employment status account for most of the apparent association with bottle feeding. 相似文献
96.
Kenneth P. Gilbert Gary Lewis Richard P. Billingham Eric Sanderson 《The Western journal of medicine》1984,140(4):569-572
A 30-year retrospective review of 544,354 Seattle area hospital admissions yielded 25 patients who underwent surgical therapy for the relief of intractable idiopathic constipation. All patients were refractory to conventional medical treatment consisting of the daily use of laxatives, cathartics, emollients or enemas. Long-term follow-up was available for 13 of the 25 patients. All 13 patients had clinical improvement as a result of the operation. This confirms results reported by other authors. Subtotal colectomy and left hemicolectomy are the procedures generally favored. 相似文献
97.
Jean-Claude Dreyfus Jean-Paul Belon Sophie Gautron Gilbert Lenoir Livia Poenaru 《Biochemical and biophysical research communications》1984,119(3):841-849
The activity of seven lysosomal enzymes was determined in 25 lymphoblastoid cell lines. These lines included normal controls transformed with Epstein-Barr virus, Burkitt's lymphomas and other lymphomas with or without EBV genome.Four lines were deficient in total β-hexosaminidase activity. The deficiency was as severe as that of the variant O (Sandhoff's disease) of clinical β-hexosaminidase deficiency. The electrophoretic pattern was also similar to that observed in Sandhoff's disease.The possible mechanisms explaining the high frequency of β-hexosaminidase deficiency in lymphoblastoid cell lines are discussed. 相似文献
98.
99.
Amino groups in the pyridoxal phosphate, pyridoxamine phosphate, and apo forms of pig heart cytoplasmic aspartate aminotransferase (L-aspartate: 2-oxoglutarate aminotransferase, EC .2.6.1.1) have been reversibly modified with 2,4-pentanedione. The rate of modification has been measured spectrophotometrically by observing the formation of the enamine produced and this rate has been compared with the rate of loss of catalytic activity for all three forms of the enzyme. Of the 21 amino groups per 46 500 molecular weight, approx. 16 can be modified in the pyridoxal phosphate form with less than a 50% change in the catalytic activity of the enzyme. A slow inactivation occurs which is probably due to reaction of 2,4-pentanedione with the enzyme-bound pyridoxal phosphate. The pyridoxamine phosphate enzyme is completely inactivated by reaction with 2,4-pentanedione. The inactivation of the pyridoxamine phosphate enzyme is not inhibited by substrate analogs. A single lysine residue in the apoenzyme reacts approx. 100 times faster with 2,4-pentanedione than do other amino groups. This lysine is believed to be lysine-258, which forms a Schiff base with pyridoxal phosphate in the holoenzyme. 相似文献
100.