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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.
Background and Aim:  PGE1 reduces in vivo and in vitro D-galactosamine (D-GalN)-induced cell death in hepatocytes. The present study was undertaken to elucidate the intracellular pathway by which D-GalN induces cell death in cultured hepatocytes. In addition, we evaluated if PGE1 was able to modulate different parameters related to D-GalN-induced apoptosis in cultured rat hepatocytes.
Methods:  Hepatocytes were isolated from male Wistar rats (225–275 g) by the classical collagenase procedure. PGE1 (1 µM) was administered 2 h before D-GalN (5 mM) in primary culture of rat hepatocytes. Apoptosis was determined by DNA fragmentation and caspase-3, -6, -8 and -9 activation in hepatocytes. Caspase activation was evaluated by the detection of the related cleaved product and its associated activity. Cell necrosis was determined by the measurement of lactate dehydrogenase (LDH) activity in culture medium. To elucidate the role of mitochondria, we measured neutral (nSMase) and acid (aSMase) sphingomyelinase, as well as the expression of cytochrome c in mitochondria and cytoplasm fractions from D-GalN treated hepatocytes.
Results:  D-GalN induced caspase-3 activation and DNA fragmentation in hepatocytes. This apoptotic response was not associated with the activation of caspase-6, -8 or -9. The use of specific inhibitors confirmed that only caspase-3 was involved in D-GalN-induced apoptosis. D-GalN did not modify nSMase and aSMase activities, nor mitochondrial cytochrome c release in hepatocytes.
Conclusions:  D-GalN induced apoptosis through caspase-3 activation but without modification of the activity of caspase-6, -8, -9, SMases or cytochrome c release. PGE1 appears to prevent D-GalN-induced apoptosis by a mitochondria-independent mechanism.  相似文献   
3.
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   
4.
Summary. There are limited data on the prognostic role of biomarkers in anticoagulated patients with atrial fibrillation (AF). We evaluated the prognostic value of high sensitivity TnT (hsTnT) and high‐sensitivity interleukin‐6 (hsIL6) in a large cohort of AF patients taking oral anticoagulant therapy (OAC) as both biomarkers have been associated with adverse cardiovascular events. Methods: We studied 930 patients (51% male; median age 76) with permanent/ paroxysmal AF who were stabilized (for at least 6 months) on OAC (INRs 2.0–3.0). Plasma hsTnT and hsIL6 levels were quantified by electrochemiluminescense immunoassay at baseline. Patients were followed‐up for up to 2 years, and adverse events (thrombotic and vascular events, mortality and major bleeding) were recorded. Results: At follow‐up, 96 patients (3.97%/year) died whilst 107 had an adverse cardiovascular event (3.14%/year). On multivariate analysis, high hsTnT and high hsIL6 remained significantly associated with prognosis even after adjusting for CHADS2 score: HR 2.21 (1.46–3.35, P < 0.001) for high hsTnT and 1.97 (1.29–3.02, P = 0.002) for high hsIL6, for adverse cardiovascular events. For all‐cause mortality, the HRs were 1.79 (1.13–2.83, P = 0.013) and 2.48 (1.60–3.85, P < 0.001), respectively. The integrated discrimination index (IDI) values of clinical scores (CHADS2 and CHA2DS2‐VASc) were improved by the addition of hsTnT and/or hsIL6 (all P < 0.05). Conclusion: In a large ‘real world’ cohort of anticoagulated AF patients, both hsTnT and hsIL6 levels provided prognostic information that was complementary to clinical risk scores for prediction of long‐term cardiovascular events and death, suggesting that these biomarkers may potentially be used to refine clinical risk stratification in AF.  相似文献   
5.

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   
6.
We present a rare case of fistulation of a dermoid cyst with the transverse colon. We illustrate how an infected dermoid cyst can be diagnosed as an appendix abscess although the management of these is quite different. The general surgeon should be aware of this as a differential diagnosis for an appendix abscess.  相似文献   
7.
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   
8.
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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