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A model based upon steady-state diffusion theory which describes the radial dependence of diffuse reflectance of light from tissues is developed. This model incorporates a photon dipole source in order to satisfy the tissue boundary conditions and is suitable for either refractive index matched or mismatched surfaces. The predictions of the model were compared with Monte Carlo simulations as well as experimental measurements made with tissue simulating phantoms. The model describes the reflectance data accurately to radial distances as small as 0.5 mm when compared to Monte Carlo simulations and agrees with experimental measurements to distances as small as 1 mm. A nonlinear least-squares fitting procedure has been used to determine the tissue optical properties from the radial reflectance data in both phantoms and tissues in vivo. The optical properties derived for the phantoms are within 5%-10% of those determined by other established techniques. The in vivo values are also consistent with those reported by other investigators.  相似文献   
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The past 15 years have not been easy for the doctors who manage Medical Liability Mutual. There have been many frustrations and setbacks, and at times the predictors of doom for MLMIC seemed to be correct. Despite all the difficulties, the board of directors has never deviated from its original basic principles: (1) to attempt to settle meritorious claims rapidly and to resist totally those claims without merit; (2) to invest funds with caution and prudence, while achieving the best possible return on that investment; (3) to reduce medical injury and enhance patient safety; and (4) to make every effort to change a system that does not serve the public and threatens our health care system. The next five years may well be even more hectic than the past 15 have been. We do not know the reasons for the recent apparent improvement, and the situation may well deteriorate again. It is to be hoped that major changes that will benefit the public as a whole will occur, and that in the future the concerns of professional liability will not consume as much of our time and resources as they do at present.  相似文献   
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Objective: The objectives of this study were to 1) determine the prevalance and characterize the symptomatology of Trichomonas vaginalis (TV) infection in pregnant women on entry into prenatal care in an inner-city population; 2) compare conventional microscopic methods vs. culture techniques in diagnosing TV in both symptomatic and asymptomatic pregnant patients; and 3) correlate wet mount microscopic and microbiologic characteristics of varying manifestations of trichomoniasis.Methods: One thousand two hundred sixty patients in an inner-city population were tested at entry into prenatal care for TV by saline wet mount and culture techniques. Other tests for lower genital tract infection were also performed. Vaginal symptoms were ascertained through standardized questioning prior to examination. Standard microscopic and microbiologic data were also obtained for analysis. Wet mounts were systematically examined and considered negative if no TV was identified in 10 high powerfields (HPFs). Cultures were inspected from days 4 to 7 or until positive results were obtained. Results were analyzed using McNemar's test for correlated proportions, chi-squared test, or Fisher exact test where appropriate.Results: Culture and wet mount results were available in 1,175 patients. TV infection was documented by one or both techniques in 110/1,175 (9.4%). Culture methods detected 105/110 (94.5%) of all patients while wet mount detected 90/110 (73%) (P <0.001). Vaginal symptoms were present in only 20/110 patents (18.2%). Among asymptomatic patients, culture detected 94% while wet mount detected 70% (P < 0.001). Among symptomatic patients, wet mount and culture were both effective and diagnosed 85% and 95% of infections, respectively (P = not significant). Patients with TV were more likely to have increased vaginal fluid wlaite blood cells (WBCs) and more severe vaginal flora disruption than uninfected controls. Subgroup analysis revealed wet mount-positive/culture-positive patients were more likely to have vaginal flora disruption, as evidenced by decreased lactobacilli and elevated vaginal pH, than wet mount-negative/culture-positive subjects. Coexistent infection rates were similar regardless of wet mount status. Elevated vaginal fluid WBCs were more common among patients with symptoms.Conclusions: 1) Screening pregnant women for TV based solely on symptomatology is ineffective in this population; 2) culture techniques detected more infections than conventional microscopic evaluation; and 3) significant increases in vaginal fluid WBCs and altered vaginal flora are found in both symptomatic and asymptomatic TV, suggesting that both infestations have the potential to adversely affect pregnancy outcome. Studies on the influence of TV on pregnancy outcomes are ongoing.  相似文献   
87.
The findings presented in this paper are part of a research project designed to provide a preliminary indication of the support needs of postdiagnosis women with breast cancer in remote and isolated areas in Queensland. This discussion will present data that focuses on the women's expressed personal concerns. For participants in this research a diagnosis of breast cancer involves a confrontation with their own mortality and the possibility of a reduced life span. This is a definite life crisis, creating shock and needing considerable adjustment. Along with these generic issues the participants also articulated significant issues in relation to their experience as women in a rural setting. These concerns centred around worries about how their partner and families cope during their absences for treatment, the additional burden on the family of having to cope with running the property or farm during the participant's absence or illness, added financial strain brought about by the cost of travel for treatment, maintenance of properties during absences, and problems created by time off from properties or self-employment. These findings accord with other reports of health and welfare services for rural Australian and the generic literature on psycho-oncology studies of breast cancer.  相似文献   
88.
OBJECTIVE: To develop a dietary assessment instrument to measure soy food consumption and isoflavone intake and test it for reliability. DESIGN: A soy food frequency questionnaire, designed for use in this study, was administered twice to participants, separated by a 2-week interval. The questionnaire was tested for reproducibility of estimates of soy food consumption and isoflavone (genistein and daidzein) intake. SUBJECTS/SETTING: A convenience sample of 51 faculty, staff, and students was recruited from a naturopathic university. STATISTICAL ANALYSES PERFORMED: Intraclass correlation coefficients were used to assess reproducibility of estimates of soy food intake and genistein and daidzein intake. RESULTS: Correlation coefficients comparing mean soy food servings per month between the 2 administrations of the questionnaire ranged from 0.50 for soy yogurt to 0.89 for tempeh. Correlation coefficients for genistein and daidzein intake estimated by the 2 administrations of the questionnaire were the same: 0.89. Mean intake (+/- standard deviation) of genistein and daidzein was 7 +/- 10 and 4 +/- 6 mg/day, respectively. Fifteen soy foods contributed 95% of the total genistein and daidzein intake: tofu, soy yogurt, tempeh, soy milk, low-fat tofu, soy flour, miso, soy protein isolate, low-fat soy milk, veggie soy burger, textured vegetable protein, miso soup, cooked soybeans, soy hot dogs, and natto (fermented soy beans). APPLICATIONS: The soy food frequency questionnaire developed in this study provided highly reproducible estimates of soy food consumption and isoflavone intake. This instrument may be a useful tool in studies of the associations between isoflavone exposure and risk for chronic disease.  相似文献   
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User satisfaction with realtime teleneurology   总被引:3,自引:0,他引:3  
User satisfaction (i.e. that of patients, medical staff at a remote hospital and medical staff at a neurological centre) with realtime teleneurology consultations was studied prospectively. Twenty-five patients with neurological problems admitted to a hospital without permanent neurological cover were assessed from a neurological centre by specialist neurologists using realtime video-links transmitting at 384 kbit/s. All users reported high levels of satisfaction with the technical aspects of the consultations. Patients, almost universally, reported confidence in teleneurology as a means of dealing with their presenting complaints. Similarly, medical staff at either site felt confident in managing patients using teleneurology and almost always felt that a telephone consultation would not have achieved as good an outcome. No major organizational problems were identified. These findings suggest overall user satisfaction with realtime teleneurology for managing patients with neurological problems admitted to hospitals that do not have resident neurologists.  相似文献   
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