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1.
Systemic disease may present first in the foot. The authors present a case in which the marrow of resected bone tissue from a phalanx showed the changes of chronic lymphocytic leukemia (CLL). Subsequent blood examination confirmed this diagnosis.  相似文献   
2.
目的探讨西藏拉萨地区幽门螺杆菌(Helicobacter pyloric,Hp)感染与冠心病及多种危险因素的关系。为该地区冠心病的防治提供依据。方法分为冠心病组46例和非冠心病组51例,应用检测血抗HpIgG及-C-尿素呼气试验方法检测Hp感染情况,并分别测定各组血脂、血糖、餐后2h血糖、C反应蛋白、纤维蛋白原、白细胞总数。结果冠心病组患者血清抗HpIgG阳性率为50.0%(23/46),明显高于非冠心病组的23.5%(12/51),P〈0.05;冠心病患者Hp现症感染率为54.3%(25/46),明显高于非冠心病组的31.3%(27/51),P〈0.05;冠心病组Hp感染患者血脂、空腹及餐后2h血糖、C反应蛋白、纤维蛋白原较非感染患者明显升高(P〈0.05)。结论Hp感染与冠心病相关,可能是拉萨地区冠心病发病的独立危险因素。  相似文献   
3.
Hecht  SS; Ronai  ZA; Dolan  L; Desai  D; Amin  S 《Carcinogenesis》1998,19(1):157-160
We compared the tumor-initiating activities toward mouse skin of two structurally related polycyclic aromatic hydrocarbon diol epoxides: racemic anti-1,2,3,4-tetrahydro-5,6-dimethylchrysene-1,2-diol-3,4- epoxide (5,6-diMeCDE) and racemic anti-1,2,3,4-tetrahydro-5- methylchrysene-1,2-diol-3,4-epoxide (5-MeCDE). Tumors induced by these diol epoxides were analysed for mutations in the Ha-ras gene. 5,6- diMeCDE is derived from the non-planar parent compound 5,6- dimethylchrysene, and reacts to approximately equal extents with dA and dG in DNA, whereas 5-MeCDE is derived from a nearly planar parent compound, 5-methylchrysene, and reacts mainly with dG in DNA. 5,6- diMeCDE, at initiating doses of 33, 100 or 400 nmol per mouse, induced 1.2, 2.2 and 6.2 skin tumors per mouse, respectively. It was significantly less tumorigenic than 5-MeCDE which induced 3.1, 7.5 and 9.1 skin tumors per mouse at the same doses. Tumors induced by 5,6- diMeCDE had a large number of CAA-->CTA mutations in codon 61 of the Ha- ras gene: 50, 55 and 75% of the tumors analysed had this mutation at the 33, 100 and 400 nmol doses. No mutations were found in codons 12 and 13 in the tumors induced by 5,6-diMeCDE. In contrast, CAA-->CTA mutations in codon 61 were rarely seen in tumors induced by 5-MeCDE. At the highest dose of 5-MeCDE, 20% of the tumors analysed had mutations at G of codons 12 and 13. The results of this comparative study support the hypothesis that mutations in the Ha-ras gene in mouse skin tumors induced by PAH diol epoxides occur as a result of their direct reaction with the gene. However, pathways other than the commonly observed Ha- ras codon 61 mutations are clearly important in mouse skin tumorigenesis by these diol epoxides.   相似文献   
4.
BACKGROUND: This study examined whether an operative product and time to completion could serve as measures of technical skill. METHODS: Nine final-year (PGY5) and 11 penultimate-year (PGY4) general surgery residents participated in a 6-station bench model examination. Time to completion was recorded. Twelve faculty surgeons (2 per station) evaluated the quality of the final product using a 5-point scale. RESULTS:The mean interrater reliability was 0. 59 for product quality. Interstation reliability was 0.59 for analysis of the final product and 0.72 for time to completion. There was 63% and 78% agreement between attendings' ratings and product quality and time scores respectively. PGY5s' mean product quality score was 4.14 +/- 0.26, compared with 3.82 +/- 0.33 for PGY4s (P < 0.05). PGY5s' mean time was 110 +/- 19 minutes compared with PGY4s' 132 +/- 15 (P < 0.05). CONCLUSIONS: Analysis of the operative end product and time to completion offer efficient alternatives to on-line examiner scoring for bench model examinations of technical competence.  相似文献   
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6.

Purpose

Video feedback and faculty feedback has been shown to improve surgical performance; however, consistent access to faculty is challenging. We studied the utility of structured peer-feedback (PF) compared to faculty-feedback (FF) during acquisition of basic and intermediate surgical skills.

Methodology

Two randomized non-inferiority trials were conducted with 1st (n?=?30) and 2nd year (n?=?29) medical students learning skin-lesion excision and closure (S), and single-layer hand-sewn bowel anastomosis (B), respectively. Five attempts were performed. PF participants used an Objective Structured Assessment of Technical Skills tool to guide feedback. Blinded raters assessed video-recorded performance, time and Integrity of the completed task were also assessed.

Results

For both tasks performance by PF was comparable to FF (P?=?0.111). Both groups improved significantly: performance (B:P?<?0.0001, S:P?=?0.035), time (B:P?=?0.043, S:P?<?0.0001) and integrity (B:P?<?0.0001, S:P?<?0.032).

Conclusion

Structured peer-feedback is equivalent to faculty-feedback in the acquisition of basic and intermediate surgical skills, giving students freedom to practice independently.  相似文献   
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Despite the significant health risks resulting from tobacco use, the prevalence of smokers worldwide remains high. Cigarette smoking is one of the major sources of toxic chemical exposure to humans and is the greatest cause of preventable illnesses and premature death. The adverse consequences of smoking in various pathologies are mediated by its effects on the immune-inflammatory system. In this review, we aim to explore the effects of cigarette smoking on the inflammatory response and molecular mechanisms with emphasis on the nuclear factor kappa B (NF-kB) pathway. The effects of smoking on various inflammatory pathologies will be discussed, focusing on oral diseases, airway inflammation, chronic obstructive pulmonary disease (COPD) and inflammatory bowel diseases (IBD).  相似文献   
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10.
This study explored North Carolina pediatric healthcare professional’s (PHP) perceptions of screening 12–18 month old infants for Autism Spectrum Disorder (ASD). Eight focus groups (66 PHPs) were conducted across practice settings. The purpose was to explore PHP’s perspectives to: inform development of ASD screening tools and ultimately impact their use in PHP settings. PHPs reported concerns, barriers, and the need for research to support early ASD screening. Additionally, they expressed the need for: (a) clear “red flags” of ASD for 12–18 month olds; (b) socioculturally sensitive and effective screening tools; (c) effective early interventions; (d) systems to handle potential increases in referrals; and (e) continuing education. PHPs also demonstrated preferences about screening tool characteristics and processes for enhancing screening efforts.  相似文献   
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