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691.

Background  

Machine perfusion (MP) has potential benefits for marginal organs such as from deceased from cardiac death donors (DCD). However, there is still no consensus on MP benefits. We aimed to determine machine perfusion benefits on kidney grafts.  相似文献   
692.
A stiff skin forms on surface areas of a flat polydimethylsiloxane (PDMS) upon exposure to focused ion beam (FIB) leading to ordered surface wrinkles. By controlling the FIB fluence and area of exposure of the PDMS, one can create a variety of patterns in the wavelengths in the micrometer to submicrometer range, from simple one-dimensional wrinkles to peculiar and complex hierarchical nested wrinkles. Examination of the chemical composition of the exposed PDMS reveals that the stiff skin resembles amorphous silica. Moreover, upon formation, the stiff skin tends to expand in the direction perpendicular to the direction of ion beam irradiation. The consequent mismatch strain between the stiff skin and the PDMS substrate buckles the skin, forming the wrinkle patterns. The induced strains in the stiff skin are estimated by measuring the surface length in the buckled state. Estimates of the thickness and stiffness of the stiffened surface layer are estimated by using the theory for buckled films on compliant substrates. The method provides an effective and inexpensive technique to create wrinkled hard skin patterns on surfaces of polymers for various applications.  相似文献   
693.
Mismatch between bone marrow transplant (BMT) patient and donor for an amino acid polymorphism within the adhesion molecule CD31 has recently been reported to increase risk for the development of graft-versus-host disease (GVHD). We further examined this association in a larger series of 301 BMT patients (227 with grade III/IV GVHD and 74 with grade 0 GVHD) and their HLA-identical sibling donors. CD31 genotypes were determined by polymerase chain reaction and restriction endonuclease digestion. The role of mismatch at the CD31 locus in the development of GVHD was assessed by analyzing the extent of CD31 identity and CD31 compatibility among the grade 0 GVHD and grade III/IV GVHD sibling pairs. No significant association between CD31 mismatch and the development of severe GVHD was detected in our overall patient population. Sixty-three percent of grade III/IV GVHD sibling pairs and 69% of grade 0 GVHD sibling pairs had CD31 genotypes that were identical (P = .36, odds ratio = 1.30). In addition, neither the grade 0 GVHD group (P = .10) nor the grade III/IV GVHD group (P = .27) differed significantly from the expected probability of identity between sibling pairs. Mismatch at the CD31 polymorphism between recipients and donors showed no consistent association with the development of GVHD. Current evidence does not support the value of CD31 mismatch in the selection of BMT donors.  相似文献   
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Participatory and patient-centered approaches to cancer research have been highlighted as the most appropriate means of engaging patients in the conduct of clinical research. However, there is a paucity of patient-centered outcomes research (PCOR) on lung cancer. Previous studies seeking to define lung cancer treatment success have generally not included patients’ and caregivers’ perceptions and views in treatment decision-making. Additionally, little is known about effective strategies for the engagement of lung cancer patients in PCOR. We sought to gain insights into the perceptions of patients, caregivers, and providers on lung cancer treatment success, as well as on strategies for patient engagement in lung cancer PCOR. Four focus groups were conducted with provider, patient, and caregiver participants from four cancer centers in Nebraska and South Dakota. A total of 36 providers, patients, and caregivers participated in this study. Patients and caregivers confirmed that survival alone should not be the measure of lung cancer treatment success and that definitions of treatment success should emphasize factors such as effective clinical guidance throughout treatment, symptom management, functionality, and quality of life. Clinician participants noted that the definition of treatment success evolved over time and appeared to be linked to patients’ experiences with chemotherapy. Participants identified barriers to and facilitators of research participation and suggested strategies for the recruitment and retention of research participants. Our study indicates that patients can successfully play active and engaged roles in clinical research, ranging from participant to partner. Judging from the enthusiasm of our focus group attendees, patients and caregivers want to participate and be engaged in clinical research.  相似文献   
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