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排序方式: 共有3114条查询结果,搜索用时 31 毫秒
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Alison Patrick Michael Seluanov Chaewon Hwang Jonathan Tam Tanya Khan Ari Morgenstern Lauren Wiener Juan M. Vazquez Hiba Zafar Robert Wen Malika Muratkalyeva Katherine Doerig Maria Zagorulya Lauren Cole Sophia Catalano Aliny AB Lobo Ladd A. Augusto Coppi Yüksel Co?kun Xiao Tian Julia Ablaeva Eviatar Nevo Vadim N. Gladyshev Zhengdong D. Zhang Jan Vijg Andrei Seluanov Vera Gorbunova 《Aging》2016,8(5):841-847
Differences in the way human and mouse fibroblasts experience senescence in culture had long puzzled researchers. While senescence of human cells is mediated by telomere shortening, Parrinello et al. demonstrated that senescence of mouse cells is caused by extreme oxygen sensitivity. It was hypothesized that the striking difference in oxygen sensitivity between mouse and human cells explains their different rates of aging. To test if this hypothesis is broadly applicable, we cultured cells from 16 rodent species with diverse lifespans in 3% and 21% oxygen and compared their growth rates. Unexpectedly, fibroblasts derived from laboratory mouse strains were the only cells demonstrating extreme sensitivity to oxygen. Cells from hamster, muskrat, woodchuck, capybara, blind mole rat, paca, squirrel, beaver, naked mole rat and wild-caught mice were mildly sensitive to oxygen, while cells from rat, gerbil, deer mouse, chipmunk, guinea pig and chinchilla showed no difference in the growth rate between 3% and 21% oxygen. We conclude that, although the growth of primary fibroblasts is generally improved by maintaining cells in 3% oxygen, the extreme oxygen sensitivity is a peculiarity of laboratory mouse strains, possibly related to their very long telomeres, and fibroblast oxygen sensitivity does not directly correlate with species'' lifespan. 相似文献
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Yair Herishanu Tamar Tadmor Andrei Braester Osnat Bairey Ariel Aviv Naomi Rahimi‐Levene Riva Fineman Itai Levi Mona Yuklea Rosa Ruchlemer Lev Shvidel Aaron Polliack 《Hematological oncology》2019,37(2):185-192
Chronic lymphocytic leukemia (CLL) is a disease of elderly patients. The fludarabine, cyclophosphamide, and rituximab (FCR) regimen is considered the treatment of choice for young fit patients with CLL; however, this combination is toxic for older patients. At the time this study was first planned and initiated, there was no standard chemo‐immunotherapy regimen regarded as standard therapy for the less fit elderly patient with CLL. Here, we conducted a single‐arm, phase II trial to examine the efficacy and safety of lower‐dose fludarabine and cyclophosphamide combined with a standard dose of rituximab (LD‐FCR) in elderly patients with previously untreated CLL. Forty patients received LD‐FCR and were included in the efficacy analysis. Two patients treated with FC alone were only included in the safety analysis. The median age was 72.7 years (range, 65.0 to 85.0). The overall response and complete response rates were 67.5% and 42.5%, respectively. Median progression‐free survival (PFS) was 35.5 months (95% CI, 29.27‐41.67). Two patients (4.8%) died during the study period. Hematological toxicities and infections were the most common complications encountered; grade 3 to 4 treatment‐related neutropenia occurred in 20 (47.6%) patients. During the entire study follow‐up, 26 patients (61.9%) had all grades of infection including six (14.3%) with neutropenic fever and eight (19%) with grade 3 to 4 non‐neutropenic infections. In conclusion, LD‐FCR is an effective and relatively safe regimen for previously untreated patients with CLL. It has the advantage of being both “time and cost limited” and, even in the era of novel agents, can still be considered when planning treatment for elderly patients without high‐risk biomarkers. However, recent results in fit elderly patients using the combination of bendamustine and rituximab which have achieved longer PFS with good safety profile must be taken into consideration in this regard. 相似文献
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Steven I. Park MD Steven M. Horwitz MD Francine M. Foss MD Lauren C. Pinter-Brown MD Kenneth R. Carson MD PhD Steven T. Rosen MD Barbara Pro MD Eric D. Hsi MD Massimo Federico MD Christian Gisselbrecht MD Marc Schwartz Lisa A. Bellm MIM Mark Acosta PharmD Ranjana H. Advani MD Tatyana Feldman MD Mary Jo Lechowicz MD Sonali M. Smith MD Frederick Lansigan MD Anil Tulpule MD Michael D. Craig MD John P. Greer MD Brad S. Kahl MD Joseph W. Leach MD Neil Morganstein MD Carla Casulo MD Andrei R. Shustov MD for the COMPLETE Investigators 《Cancer》2019,125(9):1507-1517
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Evgeny Sidorov Courtney Iser Nidhi Kapoor Bappaditya Ray Juliane Chainakul Chao Xu Andrei V. Alexandrov David Lee Gordon 《Journal of stroke and cerebrovascular diseases》2021,30(8):105890
ObjectivesIntravenous (IV) tissue plasminogen activator (tPA) should be given to patients with acute ischemic stroke (AIS) and avoided in stroke mimics (SM). Select use of emergency brain magnetic resonance imaging (eMRI-brain) in stroke-alerts aids diagnosis, but accepted utilization criteria for eMRI-brain do not currently exist. We developed criteria for eMRI-brain and report the yield of eMRI-brain in stroke-alert patients.Materials and MethodsWe developed three history-based criteria for performing eMRI-brain during stroke-alerts: (1) history of previous similar deficits, (2) change in consciousness at onset of symptoms, (3) symptom presentation consistent with migraine aura. We then performed a retrospective chart review of patients who presented as a stroke-alert over a 5-year period and determined how these criteria affected administration of IV tPA to AIS and SM patients.ResultsAmong 3,512 stroke-alerts, 230 (8.1%) patients met our criteria for eMRI-brain exams: 217 (92.6%) had SM and 17 (7.4%) had AIS. Our IV tPA decision-making analysis showed that based on eMRI-brain IV tPA was less frequently administered to SM patients (PCC-0.841, p=0.036) with less failures to administer IV tPA to patients with AIS (PCC -0.907, p-value=0.013, Pearson correlation coefficient). No patients became ineligible for IV tPA due to MRI-related time delays.ConclusionsOur history based criteria for performing eMRI-brain during stroke-alerts show a high yield of stroke mimics. Selective eMRI-brain improves decision-making accuracy regarding IV tPA administration. 相似文献