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101.
Lorien Abroms Cynthia M Jorgensen Brian G Southwell Alan C Geller Karen M Emmons 《Health education & behavior》2003,30(1):29-43
This study employs focus group methodology to explore gender differences in sunscreen use. Guided by the theory of reasoned action, males and females were found to differ on each of the following constructs: behavior, behavioral beliefs, and normative beliefs. Males and females differed in their sunscreen use, with females adopting a more preventive style of sunscreen use and males a more reactive style. Males and females differed in their salient beliefs that motivated their sunscreen use, many of which were related to traditional American gender roles. In addition, although males and females were aware of both positive and negative sources of normative beliefs regarding sunscreen use, females received more encouragement from their mothers and peers than males. Findings are discussed in terms of their implications for the design of future interventions. 相似文献
102.
Multiplex PCR analysis of in vivo-arising deletion mutations in the hprt gene of human T-lymphocytes
James C. Fuscoe Lisa J. Zimmerman Karen Harrington-Brock Martha M. Moore 《Environmental and molecular mutagenesis》1994,23(2):89-95
A multiplex polymerase chain reaction (PCR) procedure was adapted for the rapid and efficient evaluation of deletions of the hypoxanthine guanine phosphoribosyltransferase (hprt) gene in human T-lymphocytes. The hprt clonal assay was used to isolate in vivo-arising hprt-deficient T-cells from six healthy males. Mutant frequencies ranged from 9-27 × 10?6. Simple crude cellular extracts from 223 mutants were analyzed for hprt gene deletion. Sixteen (7.2%) were found to be due to total gene deletion and 22 (9.9%) were due to partial gene deletion. The relatively high frequency of total gene deletions was caused by replicate isolates of a single mutational event as shown by single-strand conformation polymorphism (SSCP) analysis of rearranged T-cell receptor (TCR)-γ genes. Eighteen of the 22 partial hprt gene deletion mutants were determined to be of independent origin based on a unique hprt mutation or SSCP-TCR-γ pattern. One-half (9/18) of the partial deletion mutants involved all or part of exon 4 alone, suggesting that this region of the hprt gene is prone to deletion. The small deletions effecting exon 1 (1 mutant), exon 2 (2 mutants), and exon 4 (6 mutants) would not have been detected by conventional Southern blot analysis and may represent a new, previously unrecognized class of mutations. The ready isolation of such intragenic deletions will allow the characterization of breakpoint junctions and may provide insights into the important processes of DNA breakage and rejoining. © 1994 Wiley-Liss, Inc. 相似文献
103.
目前,室管膜下瘤的组织学起源仍不明确。但很可能来源于室管膜下层的胶质细胞。此类肿瘤呈膨胀性生长.是生长缓慢、非侵袭性的一种低级别胶质瘤,有症状者非常少见.至今国内外文献报道的有症状病例仅百余例。本文报道了我科收治的2例颅内室管膜下瘤患者的临床特点、影像学特点、和手术治疗效果。 相似文献
104.
105.
The goblet cell density in the nasai inferior fornical conjunctiva was determined in 43 normal subjects (57 eyes). The mean number of goblets per 100 epithelial cells was found to be 10.17 +/- 2.81 in the young averaging 25 years and 5.25 +/- 3.38 in the aged averaging 62 years (P less than 0.01). The relation between the morphological features of the epithelial cells and the number of goblet cells was discussed. 相似文献
106.
107.
David F Kroon M Louise Lawson Craig S Derkay Karen Hoffmann Joe McCook 《Otolaryngology--head and neck surgery》2002,126(5):499-504
OBJECTIVE: The study goal was to demonstrate the prevalence and severity of external auditory exostoses (EAEs) in a population of surfers and to examine the relationship between these lesions and the length of time surfed as well as water temperature in which the swimmers surfed. It was hypothesized that subjects who predominantly surfed in colder waters had more frequent and more severe exostoses. METHODS: Two hundred two avid surfers (91% male and 9% female, median age 17 years) were included in the study. EAEs were graded based on the extent of external auditory canal patency; grades of normal (100% patency), mild (66% to 99% patency), and moderate-severe (<66% patency) were assigned. Otoscopic findings were correlated with data collected via questionnaires that detailed surfing habits. RESULTS: There was a 38% overall prevalence of EAEs, with 69% of lesions graded as mild and 31% graded as moderate-severe. Professional surfers (odds ratio 3.8) and those subjects who surfed predominantly in colder waters (odds ratio 5.8) were found to be at a significantly increased risk for the development of EAEs. The number of years surfed was also found to be significant, increasing one's risk for developing an exostosis by 12% per year and for developing more severe lesions by 10% per year. Individuals who had moderate-severe EAEs were significantly more likely to be willing to surf in colder waters than were those who had mild EAEs (odds ratio 4.3). CONCLUSIONS: EAEs are more prevalent in cold water surfers, and additional years surfing increase one's risk not only for developing an EAE but also for developing more severe lesions. 相似文献
108.
目的 总结原位心脏移植术后急性排异反应的监测。方法 2000-01/2002-04施行11例原位心脏移植手术,结合临床表现、心电图、超声心动图、化验检查及心内膜活栓等检查,对心脏移植术后急性排异反应的监测进行分析。结果 采用临床症状+心电图+超声心电图+心肌血清学检测综合判断有6次急性排异反应,行心内膜活检证实Ⅰb级2次,Ⅲa级3次;术后常规行心内膜活检21次,仅发现急性排异反应Ⅰa或Ⅰb级5次。结论 急性排异反应是关系到心脏移植术后患者康复及愈后的重要因素,因此要及时、有效地进行监测;心内膜心肌活检是诊断急性排异反应敏感可靠的方法,但为有创性检查,有一定的并发症风险,其他多项无创性检查可作辅助指标,因此急性排异反应监测应把无创性检查与心内膜心肌活检有机地结合起来。 相似文献
109.
Karen Holopigian Jeremy Snow William Seiple Irwin Siegel 《Documenta ophthalmologica. Advances in ophthalmology》1988,70(1):103-115
Conflicting results have been obtained concerning the parametric properties of the pattern electroretinogram. These discrepancies may be due to the large amount of variability inherent in recording amplitudes. We have found the variability within a single stimulus condition to be so large (ranging from 30% to 67% of the mean value) that it could mask any underlying spatial frequency tuning. Changing the stimulus conditions failed to significantly reduce the observed variability, although changing recording conditions produced some reduction. The use of a narrower rejection band, a greater number of sweeps, and placement of the reference electrode on the ipsilateral ear (as opposed to the ipsilateral temple) combined to decrease variability of the pattern electroretinogram within a single recording session; however, intersession variability remained high. Therefore one must be careful in evaluating data from this technique, and caution is advised in its clinical use. 相似文献
110.
目的探讨高能聚焦超声刀加氟脲嘧啶、四氢叶酸治疗晚期胰腺癌临床疗效及毒副作用。方法30例经病理学或细胞学确诊的晚期胰腺癌病人先用高能聚焦超声刀(HIFU)治疗,再予氟脲嘧啶、四氢叶酸联合化疗。氟脲嘧啶500mg/m^2加入5%GNS500ml静滴持续6小时以每天1次连用5天,CF(四氢叶酸)100mg/m^2加入生理盐水250ml静滴每天1次连用5天,28天为1周期,至少治疗2个周期。结果CR1例;PR9例;MR9例;NC5例;PD6例。总有效率63%。毒副作用主要消化道反应,其他副作用轻微。结论应用HIFU局部治疗胰腺癌同时合用四氢叶酸加氟脲嘧啶全身化疗近期疗效提高明显,止痛明显达75%,副反应小,值得应用。 相似文献