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1.
Isotretinoin (Accutane Capsules) is a synthetic vitamin A compound used for treatment of recalcitrant cystic acne. It has numerous ocular toxic side effects which include anterior segment inflammation, dry eye syndrome, contact lens intolerance, altered refraction, photosensitivity, and reduced night vision. Eye care practitioners should be aware of these potential side effects and be prepared to communicate with the prescribing physician if side effects present.  相似文献   
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This paper reports results of an open prospective study of 26 patients who met DSM-III criteria for panic disorder or agoraphobia with panic attacks. Cognitive-behavioral treatment alone produced clinically and statistically significant improvement in panic symptoms, including both full-blown and limited symptom episodes. In addition, the treatment produced improvement in associated symptoms of phobic avoidance and generalized anxiety. This work provides further preliminary indication of the usefulness of cognitive-behavioral strategies as an alternative to medication in symptom-oriented treatments.  相似文献   
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Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
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人体液中喷布洛尔及其代谢物的GC/MS分析   总被引:1,自引:0,他引:1  
用气相色谱一质谱联用(GC-MSD)系统分析方法检出了人尿中喷布洛尔的6个羟化代谢物,用Scp-Pak柱提取的方法检出了人血浆中的原型药物。并从分子结构上对此药物的代谢途径进行了研究。尿中提取和血中提取的回收率分别为90.83.%和85.88%,Gc-MSD的检测限为5pg。本方法适用于运动员兴奋剂的系统检查。  相似文献   
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Conclusion In conclusion, programmed stimulation is an excellent and appropriate method to guide thrapy for life-threatening and potentially life-threatening arrhythmias that occur infrequently and with unpredictable timing.The sensitivity and specificity of programmed stimulation is excellent in patients whose clinical presentation is by sustained uniform ventricular tachycardia and cardiac arrest. In contrast, such parameters are substantially less in patients with nonsustained ventricular tachycardia and in those who present wit syncope. The predictive accuracy of therapy guided by programmed electrical stimulation in cohorts with cardiac artest and sustained uniform ventricular tachycardia cohorts is reasonably well established and appears to be very good. Although no large randomized controlled comparative study of noninvasive versus PES-guided therapy has yet been completed, preliminary evidence suggests that there is a decreased incidence of arrhythmia recurrence and sudden cardiac death when therapy is guided by PES. In the minority of patients with syncope in whom sustained uniform ventricular tachycardia is induced during PES, therapy may be effectively guided by this modality. PES appears to be of benefit in managing patients with coronary artery disease who present with nonsustained ventricular tachycardia and depressed ejection fraction thereby defining a high risk subset for a subsequent arrhythmic event. However, we have not found electrophysiologic testing postmyocardial infarction to be prognostically useful.Dr. Josephson is the Robinette Foundation Professor of Medicine (Cardiovascular Diseases)Supported in part by grants from the American Heart Association, Southeastern Pennsylvania Chapter, Philadelphia, PA; and National Heart, Lung, and Blood Institute, Bethesda, MD (HL28093, HL07346, HL24278).  相似文献   
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Monovision vs. aspheric bifocal contact lenses: a crossover study   总被引:1,自引:0,他引:1  
Twenty selected presbyopic patients were fitted with both monovision correction and Hydrocurve bifocal contact lens correction in a crossover study. Eighty percent of the population preferred bifocal correction and 20% preferred monovision. The results suggest that bifocal contact lens correction should be explored prior to considering monovision correction.  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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