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101.
Aboriginal preschool and school children were surveyed in the Eastern Goldfields Region and the Eastern Kimberley Region of Western Australia between 1979 and 1985. Statistics from these surveys show that there has been an apparent change in pattern of follicular trachoma since the National Trachoma and Eye Health Programme in some of the communities. The prevalence of follicular trachoma in the 0 to 9 year old age groups had declined from 26.4% in 1977 to 8.8% in 1984/1985 in the Eastern Goldfields and Red Centre combined (0.10 greater than p greater than 0.05). The prevalence reduction occurred in areas where there have been improvements in school hygiene and housing. The prevalence of cicatricial trachoma has also apparently declined from 65% in 1977 to 39% in 1985 in the Red Centre, from 39% in 1977 in the Eastern Goldfields to 21.7% in 1985, and from 58% in 1977 to 24.9% in 1985 in the Eastern Kimberley, Communities at risk were identified and recommendations made for frequency of continued screening, depending on age, distribution and location.  相似文献   
102.
Abstract: We examined whether hyperacute rejection (HAR) of a discordant xenograft in a nonhuman primate model could be inhibited by the anticomplement agents, FUT-175 (FUT) and K76COOH (K76). The inhibitory effect of FUT and K76 on baboon sera was studied in vitro by i) complement-mediated hemolysis of sheep erythrocytes (by measuring serum CH50) and ii) cytotoxicity to cultured pig kidney (PK15) cells. The in vivo administration of FUT (at 0.2–25 mg/kg/h i.v. continuously) and K76 (50 mg/kg i.v. bolus) allowed evaluation of the serum levels of these drugs. Both FUT and K76 inhibited serum CH50 in a concentration-dependent manner. An enhanced effect was obtained by combining K76 with FUT therapy. High concentrations of FUT (>10-4 M) and K76 (>103 μxg/ml) were necessary to suppress serum CH50 to <5% of the normal level. However, PK15 cytotoxicity remained at >50% in the presence of i) 10-4 M of FUT, ii) 103 μg/ml of K76, and iii) 10-6 M of FUT + 103 μg/ml of K76. Pig heart transplantation (HTX) was performed in two baboons receiving FUT (1 mg/kg/h i.v. continuously) and K76 (at 200 mg/kg ×1 or 400 mg/kg + 200 mg/kg × 2 i.v, respectively). Cytotoxicity of the serum to PK15 cells at the time of HTX showed 39% and 1% cell death, respectively, in these two baboons, and the CH50 level was 1% (of control level) and 0%, respectively. Graft survival was 4.5 hours and 10 hours (with death of the baboon), respectively (compared with a mean of 29 minutes in control experiments). Both excised grafts showed typical features of hyperacute rejection. Immunopathological studies revealed deposition of C1q, C3d, C6, properdin, and Factor B, demonstrating that complement activation was not fully inhibited by FUT and K76. We conclude that i) FUT and K76 are indeed potent complement inhibitors, ii) the dosages of FUT and K76 necessary to suppress complement-mediated injury cannot be extrapolated from previously reported data obtained from serum CH50 levels, and iii) higher (possibly toxic) dosages will be required to inhibit complement activation completely. It seems unlikely that HAR will be prevented by these drugs alone, although they may be beneficial when combined with other forms of therapy.  相似文献   
103.
This paper is concerned with a study that was carried out into the effects of residential schooling on boys of secondary school age with emotional and behavioral difficulties (Cooper, 1989). The particular and original focus of the study was pupil experience in two residential schools as revealed through the perceptions of the pupils themselves. The paper reports the reasons for mounting such a study, the methodology used, and the conclusions reached. It is suggested that there is an urgent need for further qualitative studies of this type in this and other areas of special education.Reprinted with permission fromTherapeutic Care and Education, Vol. 1, No. 1, Spring 1992, 22–34.  相似文献   
104.
OBJECTIVE: To evaluate an enriched prenatal intervention program designed to reduce the risk of low birth weight. STUDY SETTING: Freestanding community-based prenatal intervention project located in a poor inner-city community, serving mostly African American women. STUDY DESIGN: All women less than 29 weeks pregnant were eligible to participate. They were compared to women who lived in neighborhoods with similar rates of poverty. DATA COLLECTION: The birth certificate was the source of data on maternal age, education, marital status, timing and frequency of prenatal care attendance, parity, gravidity, prior pregnancy terminations, fetal and child deaths, and birth weight. PRINCIPAL FINDINGS: Thirty-eight percent of the women who delivered live-born infants in the study area participated in the program. There were no differences in low- and very low birthweight rates in the study and comparison groups. In a secondary analysis comparing participants and nonparticipants in the study census tracts, participants were at higher risk for low and very low birth weight, and they adhered more closely to the schedule of prenatal visits than nonparticipants. Low- and very low birthweight rates were lower among participants than among nonparticipants and comparison women. CONCLUSION: The Better Babies Project did not have an effect on the overall low- and very low birthweight rates in the study census tracts. This was probably due to the low participation rates and the high population mobility.  相似文献   
105.
The Occupational Stress Indicator (OSI) was translated into Brazilian Portuguese and administered to a sample of 84 white-collar workers in Brazil. Five of the six scales of the OSI (job satisfaction, mental and physical health, coping, type A behaviour, sources of stress) showed acceptable reliability. The reliability of the sixth scale (locus of control) was disappointing, in keeping with earlier findings that suggest that this scale requires further development. Alternative measures of the stress outcomes — job satisfaction, mental health and physical health — were taken in order to assess the construct validity of these three scales. These measures included translations of the Hackman-Oldham job satisfaction measure and the Crown–Crisp Experiential Index, as well as subjective measures of health-related behaviours. Correlational and multivariate analyses of these data suggested that the job satisfaction, mental health and physical health scales of the OSI had good validity, with the physical health measure probably including a psychosomatic component. These findings are promising for the development of a new version of the OSI designed for use in South America.  相似文献   
106.
The poor quality of early evaluations of magnetic resonance imaging   总被引:7,自引:0,他引:7  
L S Cooper  T C Chalmers  M McCally  J Berrier  H S Sacks 《JAMA》1988,259(22):3277-3280
To study the quality of early research on the clinical efficacy of diagnostic imaging with magnetic resonance, we assessed 54 evaluations published in the first four years after introduction of this modality using ten commonly accepted criteria of research methodology. The terms sensitivity, specificity, false-positive or false-negative, accuracy, and predictive values were used infrequently. Nineteen percent of the evaluations used three terms appropriately, 48% used one or two terms, and 33% used none. Data were presented appropriately for one or more of the five terms in 59% of evaluations. A "gold standard" comparison with the results of an independent procedure, such as surgical or autopsy findings, was presented in 22% of evaluations. Results of another imaging procedure were described in 63% of evaluations. Only one evaluation clearly described a prospective study design, although 11 evaluations apparently were planned in advance. Not one evaluation contained an appropriate statistical analysis of the distributions of quantitative readings, "blinded" image readers to diagnosis or other test results, measured observer error, or randomized the order of magnetic resonance imaging and other imaging procedures. We conclude that health care professionals paying for expensive innovative diagnostic technology should demand better research on diagnostic efficacy.  相似文献   
107.
Hypoxemia is a nearly constant accompaniment of head injury. Diverse theories have been proposed to explain this relationship. The authors report the case of a patient who suffered an episode of severe, transient, arterial oxygen desaturation during "controlled" brain trauma: an otherwise uneventful stereotaxic biopsy of a small germinoma of the hypothalamus. Evidence is provided that pure ventilation-perfusion mismatching, without pulmonary edema, underlay the hypoxemia. The hypothalamus is intimately involved in matching pulmonary ventilation to perfusion; the hypoxemia of various brain injuries may be mediated by perturbation of this structure.  相似文献   
108.
109.
Field interviews were conducted with seven clients with disabilities for the purpose of developing design guidelines for apartments suitable for independent living. Analysis of these data generated six factors that were highly valued and felt to contribute to the success of these individuals' venture into community living. Control appears to be the central construct and to subsume the other concepts: safety/security, accessibility/mobility, function, flexibility and privacy. These findings are presented and discussed here as a working model of environmental control. These ideas are suggested as hypotheses which would need to be tested and refined further before being used as a model to guide clinical interventions.  相似文献   
110.
T lymphocytes recruited into the skin can experience several different outcomes. On the one hand, they may be recruited by adhesion molecules and chemoattractants to enter the perivascular space, but never undergo activation. Other T cells undergo activation and further differentiation under the influence of the cutaneous milieu. These activated lymphocytes then coordinate specific and non-specific immune responses characteristic of inflamed tissue. We have explored two models for studying the activation and function of skin infiltrating T lymphocytes (SIL's). In the first model, we have identified a family of Langerhans cell-related professional dendritic antigen presenting cells that exist in the epidermis and dermis of normal skin, atopic skin, and mycosis fungoides skin. These have APC abilities to activate freshly recruited resting blood T cells that are distinct from another family of macrophage-related cells abnormally present in sunburned or psoriatic skin. In the second model, we examined the function of cells that have already been recruited into the skin of patients with psoriasis and mycosis fungoides. Lesional psoriasis and mycosis fungoides T cells exhibited a variety of T cell receptor gene rearrangements, conclusively demonstrating that heterogeneous populations of T lymphocytes exist in inflamed human skin. From psoriasis, clones were identified that were particularly effective at inducing normal keratinocytes to assume "psoriatic" phenotypic features and functions. Thus, lesional psoriatic SIL's could induce HLA-DR, ICAM, and CDw60 on normal keratinocytes. In addition, psoriatic SIL's induced increased keratinocyte proliferation and cytokine profile changes characteristic of psoriatic epidermis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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