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Forced vital capacity, forced expiratory volume in one second, functional residual capacity, residual volume, total lung capacity, and single breath diffusing capacity measurements (effective alveolar volume, carbon monoxide transfer factor, and transfer coefficient) were measured in 247 young healthy adults (130 male, 117 female) aged 15-40 years living in Madras. Subjects were of Dravidian stock, living at sea level with rice as their staple diet. Regression equations were derived for men and women for predicting normal pulmonary function for young adults in South India. The values were similar to those reported for subjects from Western India and lower than those reported for North Indians and caucasians. 相似文献
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Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
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Vimala J Peter JV Jeyaseelan L Prabhakar S Cherian AM 《The Journal of the Association of Physicians of India》1998,46(11):930-932
Headache following lumbar puncture is a well known and well described complication. Various manoeuvres have been tried to prevent post lumbar puncture headache--the commonest being bed rest for 4 to 24 hours following lumbar puncture, though its value is questionable. Randomised controlled clinical trial was done to evaluate the effect of 24 hours bed rest on the incidence and severity of post lumbar puncture headaches. Two hundred and eight patients were randomly allocated to either the ambulant or the bed rest group. Patients were interviewed by a single investigator on days 0, 1, 2 and 7 about the presence and nature of headache. Other relevant clinical and laboratory data pertaining to the lumbar puncture was collected. The overall incidence of post lumbar puncture headache was 17%; 15% in the ambulant and 18% in the bed rest group. Of the patients who had headaches, severe headache was observed in 57% in the ambulant and 12% in the bed rest group (p = 0.02). Other variables did not alter the outcome of headaches. Bed rest does not appear to alter the incidence of post lumbar puncture headaches, but reduces the severity in those who get headaches, after a lumbar puncture. 相似文献