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61.
Changes in the membrane potential of Saccharomyces cerevisiae were monitored by the electrochromic probe 3-(4-(2-(6-(dibutylamino)-2-naphthyl)-trans- ethenyl)pyridinium)propanesulfonate (di-4-ANEPPS) that should incorporate into the plasma membrane. The probe had suitable spectral characteristics and exhibited an electrochromic shift upon a change in membrane potential but the magnitude of the response increased with time. The presence and properties of the cell wall affected the extent of cell staining. The time dependence of the fluorescent response indicated that the probe was not incorporated solely into the plasma membrane but spread gradually into the whole cell; this was confirmed by confocal microscopy. The probe is therefore suitable for assessing membrane potential changes only over time intervals up to 30 min. Longer monitoring will require either a modified staining protocol or a derivatization of the probe molecule. As found by using the dioctyl derivative di-8-ANEPPS, extending the aliphatic chains of the di-4-ANEPPS molecule does not prevent the dye from penetrating into the cell or liposome interior and, in addition, impairs staining.  相似文献   
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We reviewed the use of a low radiation portable fluoroscopy unit in 100 patients. The most common indication was closed reduction of distal radial fractures. Fracture and joint stability were assessed on the real-time monitor and stored on videotape. Static images were stored on thermographic paper. Fluoroscopically guided joint injections and localization of implants, foreign bodies and bone tumours were performed. Fluoroscopy is a useful adjunct to arthroscopic assisted fracture reduction and other arthroscopic procedures such as distal ulnar resection. These new generation units produce superior resolution images, are easy to manoeuvre and do not require a radiographer.  相似文献   
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In comparison with HLA-matched sibling bone marrow transplants, unrelated donor transplants are associated with increased graft-versus-host disease and graft failure. This is likely in part due to HLA incompatibilities not identified by current matching strategies. High resolution DNA-based typing methods for HLA class II loci have improved donor selection and treatment outcome in unrelated donor bone marrow transplantation. By using DNA-based typing methods for HLA-A and -B on a cohort of 100 potential bone marrow donor/patient pairs, we find that serological typing for HLA class I is limited in its ability to identify incompatibilities in unrelated pairs. Furthermore, the incompatibilities identified are associated with the presence at high frequency of alloreactive cytotoxic T-lymphocyte precursors. DNA typing also indicates that HLA-C mismatches are common in HLA-A and -B serologically matched pairs. Such mismatches appear to be significantly less immunogenic with respect to cytotoxic T-lymphocyte recognition, but are expected to influence natural killer cell activity. Thus, improved resolution of HLA class I shows many previously undisclosed mismatches that appear to be immunologically functional. Use of high resolution typing methods in routine matching is expected to improve unrelated donor selection and transplant outcome.  相似文献   
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BACKGROUND: Despite concerns about its prevalence and ramifications, harassment has not been well quantified among physicians. Previous published studies have been small, have surveyed only 1 site or a convenience sample, and have suffered from selection bias. METHODS: Our database is the Women Physicians' Health Study, a large (4501 respondents; response rate, 59%), nationally distributed questionnaire study. We analyzed responses concerning gender-based and sexual harassment. RESULTS: Overall, 47.7% of women physicians reported ever experiencing gender-based harassment, and 36.9% reported sexual harassment. Harassment was more common while in medical school (31% of gender-based and 20% for sexual harassment) or during internship, residency, or fellowship (29% for gender-based and 19% for sexual harassment) than in practice (25% for gender-based and 11% for sexual harassment). Respondents more likely to report gender-based harassment were physicians who were now divorced or separated and those specializing in historically male specialties, whereas those of Asian and other (nonwhite, nonblack, non-Asian, non-Hispanic) ethnicity, those living in the East, and those self-characterized as politically very conservative were less likely to report gender-based harassment. Being younger, born in the United States, or divorced or separated were correlated with reporting ever experiencing sexual harassment; those who were Asian or who were currently working in group or government settings were less likely to report it. Those who felt in control of their work environments, were satisfied with their careers, and would choose again to become physicians reported lower prevalences of ever experiencing harassment. Those with histories of depression or suicide attempts were more likely to report ever having been harassed. CONCLUSIONS: Women physicians commonly perceive that they have been harassed. Experiences of and sensitivity to harassment differ among individuals, and there may be substantial professional and personal consequences of harassment. Since reported rates of sexual harassment are higher among younger physicians, the situation may not be improving.  相似文献   
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