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排序方式: 共有783条查询结果,搜索用时 15 毫秒
1.
Factors influencing women to undergo screening mammography 总被引:2,自引:0,他引:2
2.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
3.
Design issues in studies of radon and lung cancer: implications of the joint effect of smoking and radon.
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Many case-control studies have been undertaken to assess whether and to what extent residential radon exposure is a risk factor for lung cancer. Nearly all these studies have been conducted in populations including smokers and nonsmokers. In this paper, we show that, depending on the nature of the joint effect of radon and tobacco on lung cancer risk, it may be very difficult to detect a main effect due to radon in mixed smoking and nonsmoking populations. If the joint effect is closer to additive than multiplicative, the most cost-effective way to achieve adequate statistical power may be to conduct a study among never-smokers. Because the underlying joint effect is unknown, and because many studies have been carried out among mixed smoker and nonsmoker populations, it would be desirable to conduct some studies with adequate power among never-smokers only. 相似文献
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Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
6.
M. Divine J. P. Lecouedic M. F. Gourdin N. Oudhriri M. Zohair T. Henni F. Beaujan J. P. Vernant F. Reyes J. P. Farcet 《Journal of clinical immunology》1988,8(2):140-147
The recovery of T-cell populations after bone marrow transplantation (BMT) is characterized by a persistent expansion of CD8 lymphocytes. Previously, we have shown that beyond 1 year posttransplantation the CD8 lymphocytes consist, to a large extent, of CD8+ HNK1+ cells that suppress, like normal CD8 lymphocytes, immunoglobulin productionin vitro. We have further investigated the functional capabilities of CD8 lymphocytes, mostly HNK1+ (from 50 to 77%), in seven long-term BMT patients. As normal, patient CD8 lymphocytes do not suppress (1) phytohemagglutinin (PHA)-induced interleukin 2 (IL2) receptor expression and IL2 responsiveness by normal T cells or (2) the mixed lymphocyte reaction of donor cells. Also as normal, patient CD8 lymphocytes can be activated into potent cytotoxic effectors. Therefore, under the present experimental conditions, the increase in the absolute number of CD8 lymphocytes in the long-term BMT patients is characterized by an expansion of the CD8+ HNK1+-cell subpopulation and a normal suppressor/cytotoxic potential on a per-CD8+ cell basis. 相似文献
7.
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.
相似文献
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9.
Charles H. Bombardier George W. Divine John S. Jordan W. Blair Brooks Francis A. Neelon 《Journal of behavioral medicine》1993,16(5):467-484
Cluster analysis of the MMPI has been utilized widely in the chronic low back pain literature to try to identify reliable patient subtypes predictive of treatment outcome. We extended this methodology to patients with heterogeneous chronic medical conditions by replicating prototypic MMPI cluster group profiles and by relating cluster groups to clinical baseline and outcome data. Subjects were two independent samples (n=254 and n=263) of chronically ill patients admitted to an inpatient medicine/psychiatry unit. Using a four-cluster solution, similar cluster profile groups were replicated in both samples. Consistent differences emerged between cluster groups on functional impairment, psychiatric diagnoses, depression, and psychosomatic symptoms. Cluster group membership also predicted changes in functional impairment and depression six months after treatment. Results are discussed in terms of similarities between chronic low back pain and chronic illness and tailoring treatment to different patient types.This research was supported in part by a grant from the Henry J. Kaiser Family Foundation. 相似文献
10.