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Factors influencing women to undergo screening mammography   总被引:2,自引:0,他引:2  
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In a 6-month pilot study of 7 patients with rheumatoid arthritis, we tested a treatment involving the extracorporeal photoactivation of biologically inert methoxsalen (8-methoxypsoralen) by ultraviolet A energy to a form that covalently cross-links lymphocyte DNA; the injured cells are reinfused into the patient. Prior experimental studies had indicated that this regimen produces an immune reaction against antigens on treated T cells, and a clinical trial in patients with cutaneous T cell lymphoma had been successful. The current study patients were treated monthly, on 2 successive days (or biweekly, later on). Between 12 and 16 weeks of therapy, there appeared to be a breakpoint, after which the joint counts and joint scores of 4 of the patients began to improve. In 3 of the 4 patients, these measures eventually diminished by a mean of 71% and 80% of baseline values, respectively, and there was variable improvement in less direct indicators of clinical response. The joint counts and scores of the fourth patient improved modestly (by 33% and 59% of baselines, respectively) but he required alternative therapy, and those of the remaining 3 study patients did not improve. Mean slopes for the joint counts were significantly different from zero after the apparent breakpoint (but not before), whether one examined the 4 apparent responders (P = 0.01) or the entire group of 7 patients (P = 0.01). After completion of therapy, there was also a delay, of 2-3 months, in the clinical deterioration of those patients who had improved. There was only 1 mechanical adverse effect--a single episode of transient hypotension in 102 treatment sessions--and no toxic effects.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Breast screening practices among primary physicians: reality and potential   总被引:1,自引:0,他引:1  
Increased use of regular screening mammograms and clinical breast examinations (CBE) among women aged 40 years and more could have a dramatic impact on mortality from breast cancer, but patient and physician barriers to mammography impede its acceptance. We conducted a survey of 300 primary care physicians to assess their knowledge, attitudes, beliefs, and breast screening practices. Our results show that only 71 percent of the respondents ordered mammograms for all women aged 50 to 75 years, which is the recommendation by the National Cancer Institute and American Cancer Society. Approximately 46 percent of respondents performed CBE on all women patients aged 50 to 75 years. Inadequate patient insurance coverage, equivocal radiology reports, patient reluctance or worry, and patient embarrassment all appear to be barriers to physicians' utilization of breast screening.  相似文献   
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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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