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91.
92.
This article examines C. R. Snyder's (1994, 2000a) theory of hope and its application for understanding suicide. Strengths, weaknesses, and gaps in the suicide literature are outlined, and A. T. Beck's theory of hopelessness is compared with Snyder's hope theory. Hope theory constructs are used to examine the relationship of suicide to hope/hopelessness, goals, pathways thinking, and agency thinking. This critical review is intended to broaden our theoretical understanding of suicide and is meant to form the basis for future empirical investigation of suicide-related behavior using the framework of hope theory. Implications for suicide prevention programs and approaches to treating suicidal individuals are outlined. 相似文献
93.
Anthony Brade Kevin Jao Simon Yu Parneet Cheema Sarah Doucette Anna Christofides Devin Schellenberg 《Current oncology (Toronto, Ont.)》2021,28(3):1618
Stage III non-small cell lung cancer (NSCLC) comprises a highly heterogenous group of patients with regards to patient fitness and tumour size and distribution, resulting in a wide range of treatment goals and therapy options. Curative-intent multimodality treatment should be considered in all patients with stage III NSCLC. For patients with unresectable disease who are fit, have adequate lung function, and have a disease that can be encompassed within a radical radiation volume, concurrent chemoradiation therapy (cCRT) is the standard of care and can produce cure rates of 20–30%. Recently, consolidation immunotherapy with durvalumab has been recognized as the standard of care following cCRT based on significant improvement rates in overall survival at 4 years. The large heterogeneity of the stage III NSCLC population, along with the need for extensive staging procedures, multidisciplinary care, intensive cCRT, and now consolidation therapy makes the delivery of timely and optimal treatment for these patients complex. Several logistical, communication, and education factors hinder the delivery of guideline-recommended care to patients with stage III unresectable NSCLC. This commentary discusses the potential challenges patients may encounter at different points along their care pathway that can interfere with delivery of curative-intent therapy and suggests strategies for improving care delivery. 相似文献
94.
Balneaves LG Bottorff JL Grewal SK Naidu P Johnson JL Howard AF 《Family & community health》2007,30(1):16-28
Women with breast cancer have been found to rely heavily on family members for providing support during their illness experiences. There has been limited research on ethnocultural families' experiences of illness and how these families respond to a diagnosis of breast cancer. This study examined the experiences and responses of family members of immigrant Punjabi women diagnosed with breast cancer. Through interviews with 19 Punjabi women diagnosed with breast cancer and 18 family members, key practical and emotional support strategies were described. Recommendations for culturally appropriate, family-centered models of care are provided that acknowledge breast cancer as a family event. 相似文献
95.
96.
RNA interference machinery regulates chromosome dynamics during mitosis and meiosis in fission yeast 总被引:30,自引:0,他引:30
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Hall IM Noma K Grewal SI 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(1):193-198
The regulation of higher-order chromosome structure is central to cell division and sexual reproduction. Heterochromatin assembly at the centromeres facilitates both kinetochore formation and sister chromatid cohesion, and the formation of specialized chromatin structures at telomeres serves to maintain the length of telomeric repeats, to suppress recombination, and to aid in formation of a bouquet-like structure that facilitates homologous chromosome pairing during meiosis. In fission yeast, genes encoding the Argonaute, Dicer, and RNA-dependent RNA polymerase factors involved in RNA interference (RNAi) are required for heterochromatin formation at the centromeres and mating type region. In this study, we examine the effects of deletions of the fission yeast RNAi machinery on chromosome dynamics during mitosis and meiosis. We find that the RNAi machinery is required for the accurate segregation of chromosomes. Defects in mitotic chromosome segregation are correlated with loss of cohesin at centromeres. Although the telomeres of RNAi mutants maintain silencing, length, and localization of the heterochromatin protein Swi6, we discovered defects in the proper clustering of telomeres in interphase mitotic cells. Furthermore, a small proportion of RNAi mutant cells display aberrant telomere clustering during meiotic prophase. This study demonstrates that the fission yeast RNAi machinery is required for the proper regulation of chromosome architecture during mitosis and meiosis. 相似文献
97.
A. Lo R.J. Stratta M.F. Egidi M.H. Shokouh-Amiri H.P. Grewal A.T. Kisilisik J. Trofe R.R. Alloway L.W. Gaber A.O. Gaber 《Transplant infectious disease》2001,3(1):8-15
Abstract: Background: The impact of tacrolimus (TAC), mycophenolate mofetil (MMF) and steroid immunosuppression on cytomegalovirus (CMV) infection in combination with ganciclovir prophylaxis in simultaneous kidney–pancreas transplantation (SKPT) has not been well studied. Methods: A retrospective analysis was made of 75 SKPTs performed between 1 January 1996 and 7 January 1999. All patients received ganciclovir for 3 months, but CMV donor (D)+/ recipient (R)? patients received ganciclovir for 6 months. Results: 16/74 (22%) were CMV D+/R?, 25 (33%) D+/R+, 16 (22%) D?/R+, and 17 (23%) D?/R? (1 patient with unknown donor serology was excluded). The mean time to CMV infection was 198 days post‐transplant. The incidence of either CMV infection or tissue invasive CMV disease was 16/74 (22%), including 9 (12%) with CMV infection and 7 (10%) CMV disease. The one‐year patient, kidney, and pancreas graft survival rates were 91%, 89%, and 83%, respectively. The mean follow‐up was 29 months (minimum of 12 months). CMV infection was not associated with an increased incidence of graft failure or mortality. The D+/R? group had the highest incidence of CMV infection (44%) compared with the other serologic groups (17%, P=0.02). Concurrent CMV and rejection occurred more frequently in the D+/R? than the other serologic groups (25% vs. 7%, P=0.03). The D?/R? group had the best outcomes, with no CMV infection, improved kidney graft survival at the end of follow‐up (82% vs. 72%, P=0.04) and the highest event‐free survival (no CMV infection, rejection, or graft loss) when compared to the other groups (76% vs. 33%, P<0.01). Conclusions: Compared to previous studies, ganciclovir prophylaxis delayed the onset and reduced the severity of CMV infection in patients receiving TAC, MMF, and steroids. Despite ganciclovir prophylaxis, CMV seronegative patients receiving CMV D+ organs had worse outcomes than seronegative recipients receiving CMV D? organs. 相似文献
98.
Since the Scheimpflug principle was first described over a century ago, there has been a great interest among ophthalmologists for the use of Scheimpflug camera in anterior segment imaging. Scheimpflug imaging has since advanced significantly and modern day instruments provide comprehensive imaging and topographic data of the anterior segment. In this article the clinical applications and limitations of Scheimpflug imaging in modern cataract surgery patients are discussed. This article reviews recent work on assessment of lens transparency for cataract grading and integrity, using preoperative lens density measurements to help predict phacoemulsification parameters, its utility in challenging situations like capsular bag distension syndrome and traumatic cataract and assessment of density of the posterior capsule for objectively quantifying posterior-capsule opacification. 相似文献
99.
Zhang J, Kim S, Grewal J, Albert PS. Predicting large fetuses at birth: do multiple ultrasound examinations and longitudinal statistical modelling improve prediction? Paediatric and Perinatal Epidemiology 2012; 26 : 199–207. Predicting large fetuses at birth has long been a challenge in obstetric practice. We examined whether ultrasound examinations at multiple times during pregnancy improve the accuracy of prediction using repeated, longitudinal statistical modelling, and whether adding maternal characteristics improves the accuracy of prediction. We used data from a previous study conducted in Norway and Sweden from 1986 to 1989 in which each pregnant woman had four ultrasound examinations at around 17, 25, 33 and 37 weeks of gestation. At birth, infant size was classified as large‐for‐gestational age (LGA, >90th centile) and macrosomia (>4000 g) or not. We used a longitudinal random effects model with quadratic fixed and random effects to predict term LGA and macrosomia at birth. Receiver–operator curves and mean‐squared error were used to measure accuracy of the prediction. Ultrasound examination around 37 weeks had the best accuracy in predicting LGA and macrosomia at birth. Adding multiple ultrasound examinations at earlier gestations did not improve the accuracy. Adjusting for maternal characteristics had limited impact on the accuracy of prediction. Thus, a single ultrasound examination at late gestation close to birth is the simplest method currently available to predict LGA and macrosomia. 相似文献
100.
The pressure-volume curves for 10 patients with various types of heart disease were studied throughout mid to late diastole when both pressure and volume were increasing. The results were used to test a currently held theory that the form of this relation is exponential. It was found that for the patients examined this hypothesis was not valid. 相似文献