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51.
Donatella Spina Lorenzo Leoncini Maria T. Del Vecchio Tiziana Megha Chiara Minacci Simonetta A. Poggi Stefano Piler Piero Tosi Rainer Kraft Jean A. Laissue Hans Cottier 《The Journal of pathology》1995,177(4):335-341
Cell loss, perhaps as important as cell production in determining the size of an expanding cell population, has not usually been registered in quantitative cellular kinetic analyses of neoplastic disorders. The present retrospective study on various types and subtypes of non-Hodgkin's lymphomas (NHLs; n=170) was designed to test the usefulness of a novel additional parameter, the ‘turnover index’ (TI), which is the sum per case of the mitotic index and the apoptotic index. Results document that TIs clearly distinguished between categories and subtypes of NHLs according to the Kiel classification. Cluster analysis of TIs plotted against the percentage of Ki-67-positive cells per case revealed that about one-third of the high-grade malignancy lymphomas actually belonged to the low-turnover lymphomas. Overall survival was longer in the low- than in the high-turnover group of lymphomas. Assessment of TIs can, for practical diagnostic purposes, be replaced by counting mitotic figures and apoptotic cells in several high-power fields. The TI concept may help to interpret the kinetics of NHLs in terms of accumulation vs. proliferation of cells. 相似文献
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53.
Bcl-2 expression correlates with lymphovascular invasion and long-term prognosis in breast cancer 总被引:2,自引:0,他引:2
Neri A Marrelli D Roviello F DeMarco G Mariani F DeStefano A Megha T Caruso S Corso G Cioppa T Pinto E 《Breast cancer research and treatment》2006,99(1):77-83
Summary Alterations in the mechanisms of apoptosis are responsible not only for the progression of breast cancer, but for different responses to treatment as well. Among the genes regulators of apoptosis, the tumor suppressor gene p53 and the bcl-2 gene have raised interest for their possible role as predictors of response to therapy and markers of prognosis. The purpose of our study was to prospectively analyze the prognostic value of the expression of p53 and bcl-2 genes in a series of 235 consecutive patients operated on for breast cancer at the Department of General Surgery and Surgical Oncology of the University of Siena, Italy.p53 and bcl-2 expression were evaluated by immunohistochemistry, their association with conventional clinicopathological factors was analyzed by univariate analysis and their prognostic impact was evaluated by multivariate analysis.p53 and bcl-2 were detected respectively in 15.7 and 75.7% of cases, and resulted significantly related to presence of estrogen receptors for p53 over-expression and presence of peritumor lymphovascular invasion (LVI) for bcl-2 expression.With a median follow-up of 79 months, an independent negative prognostic impact on disease free and overall survival was observed for presence of LVI, absence of bcl-2 expression and number of involved axillary lymphnodes. The expression of bcl-2 improved the prognosis of LVI positive tumors up to values similar to LVI negative cases, while its absence associated to presence of LVI resulted in a poor outcome with only 28% of patients alive at 8 years.These data may indicate that expression of bcl-2 is a marker of breast cancers with reduced capability of distant colonization, even in presence of LVI, and may be particularly useful in the clinical setting, allowing to identify a subset of patients with an high risk of relapse. 相似文献
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56.
Astroblastoma is a rare tumor belonging to the family of primary glial neoplasms. They are classified as neuroepithelial tumors; however, the World Health Organization grading is still not established. We report the case of a 4-year-old child who presented with an intra-axial space occupying lesion which turned out to be an astroblastoma. A complete excision was done and there was no recurrence at 20 months follow-up. This case report highlights the presence of such unusual tumor with invasion to the calvarium and reviews the current literature. 相似文献
57.
Introduction
The purpose of this study was to evaluate the role of efflux pumps in altering the susceptibility of Enterococcus faecalis biofilms to calcium hydroxide (Ca(OH)2), chitosan nanoparticles, and light-activated disinfection (LAD).Methods
E. faecalis as 4-day-old biofilms and biofilm-derived cells were tested with aqueous Ca(OH)2 in concentrations of 25%, 50%, and 100%; chitosan nanoparticles in concentrations of 10 and 20 mg/mL (3, 12, and 24 hours); and methylene blue (MB) mediated LAD at an energy dose range of 2–40 J/cm2. An efflux pump inhibitor (EPI) was incorporated into all 3 modalities of treatment. The antimicrobial activity was assessed by determining the colony-forming units.Results
E. faecalis biofilms, in contrast to the biofilm-derived cells, were found to persist even after 24-hour treatment with different concentrations of Ca(OH)2 and chitosan nanoparticles. LAD at an energy dose of 40 J/cm2 completely inactivated 4-day-old E. faecalis biofilms. The addition of EPI improved the antibiofilm efficacy of Ca(OH)2 at lower concentrations (P < .001) and LAD (P < .001). EPI did not influence the antibiofilm effect of chitosan nanoparticles and Ca(OH)2 at higher concentrations.Conclusions
E. faecalis biofilms were more susceptible to killing by LAD, when compared with the tested concentrations of Ca(OH)2 and chitosan nanoparticles. The effect of EPI was more significant with LAD, when compared with Ca(OH)2 and chitosan nanoparticles. This study highlighted the role of biofilm matrix in providing resistance to antimicrobials. 相似文献58.
Cutaneous complications of noninsulin-dependent, type II diabetes mellitus are reviewed, including diabetic dermopathy, necrobiosis lipoidica diabeticorum, diabetic bullae (bullosis diabeticorum), certain acquired perforating dermatoses, diabetic thick skin, scleredema adultorum, Dupuytren's contractures, certain xanthomas, carotenoderma, rubeosis faciei, and acanthosis nigricans. 相似文献
59.
Parish SJ Ramaswamy M Stein MR Kachur EK Arnsten JH 《Journal of general internal medicine》2006,21(5):453-459
BACKGROUND: Although residents commonly manage substance abuse disorders, optimal approaches to teaching these specialized interviewing and intervention skills are unknown. OBJECTIVE: We developed a Substance Abuse Objective Structured Clinical Exam (OSCE) to teach addiction medicine competencies using immediate feedback. In this study we evaluated OSCE performance, examined associations between performance and self-assessed interest and competence in substance abuse, and assessed learning during the OSCE. DESIGN: Five-station OSCE, including different substance abuse disorders and readiness to change stages, administered during postgraduate year-3 ambulatory rotations for 2 years. PARTICIPANTS: One hundred and thirty-one internal and family medicine residents. MEASUREMENTS: Faculty and standardized patients (SPs) assessed residents' general communication, assessment, management, and global skills using 4-point scales. Residents completed a pre-OSCE survey of experience, interest and competence in substance abuse, and a post-OSCE survey evaluating its educational value. Learning during the OSCE was also assessed by measuring performance improvement from the first to the final OSCE station. RESULTS: Residents performed better (P<.001) in general communication (mean+/-SD across stations=3.12+/-0.35) than assessment (2.65+/-0.32) or management (2.58+/-0.44), and overall ratings were lowest in the contemplative alcohol abuse station (2.50+/-0.83). Performance was not associated with residents' self-assessed interest or competence. Perceived educational value of the OSCE was high, and feedback improved subsequent performance. CONCLUSIONS: Although internal and family medicine residents require additional training in specialized substance abuse skills, immediate feedback provided during an OSCE helped teach needed skills for assessing and managing substance abuse disorders. 相似文献
60.
Bone disease is common in recipients of kidney, heart, lung, liver, and bone marrow transplants, and causes debilitating complications, such as osteoporosis, osteonecrosis, bone pain, and fractures. The frequency of fractures ranges from 6% to 45% for kidney transplant recipients to 22% to 42% for heart, lung, and liver transplant recipients. Bone disease in transplant patients is the sum of complex mechanisms that involve both preexisting bone disease before transplant and post-transplant bone loss due to the effects of immunosuppressive medications. Evaluation of bone disease should preferably start before the transplant or in the early post-transplant period and include assessment of bone mineral density and other metabolic factors that influence bone health. This requires close coordination between the primary care physician and transplant team. Patients should be stratified based on their fracture risk. Prevention and treatment include risk factor reduction, antiresorptive medications, such as bisphosphonates and calcitonin, calcitriol, and/or gonadal hormone replacement. A steroid-avoidance protocol may be considered. 相似文献