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31.
The Thy-1 molecule on murine T lymphocytes has been suggested to play a role in cellular activation events leading to a variety of immunologic functions. We present evidence that this molecule may be involved in signals leading to the in vitro generation of cytotoxic T cells against several tumor cell lines used as stimulators in mixed tumor-lymphocyte culture. The presence of monoclonal antibody against a polymorphic determinant on the Thy-1 molecule markedly reduced the generation of cytotoxicity after three days of culture of murine splenocytes with stimulator tumor cells bearing low levels of Ia antigen. In contrast, no effect was seen when the stimulators were either allogeneic splenocytes, or a tumor cell line expressing large amounts of Ia. These results suggest that the Thy-1 molecule is critically involved in events leading to the generation of cytotoxic effectors under some, but not all conditions. 相似文献
32.
33.
A fundamental prerequisite of population health research is the ability to establish an accurate denominator. This in turn requires that every individual in the study population is counted. However, this seemingly simple principle has become a point of conflict between researchers whose aim is to produce evidence of disparities in population health outcomes and governments whose policies promote (intentionally or not) inequalities that are the underlying causes of health disparities. Research into the health of asylum seekers is a case in point. There is a growing body of evidence documenting the adverse affects of recent changes in asylum-seeking legislation, including mandatory detention. However, much of this evidence has been dismissed by some governments as being unsound, biased and unscientific because, it is argued, evidence is derived from small samples or from case studies. Yet, it is the policies of governments that are the key barrier to the conduct of rigorous population health research on asylum seekers. In this paper, the authors discuss the challenges of counting asylum seekers and the limitations of data reported in some industrialized countries. They argue that the lack of accurate statistical data on asylum seekers has been an effective neo-conservative strategy for erasing the health inequalities in this vulnerable population, indeed a strategy that renders invisible this population. They describe some alternative strategies that may be used by researchers to obtain denominator data on hard-to-reach populations such as asylum seekers. 相似文献
34.
Sandra L. Harris Jan S. Handleman Rita Gordon Barbara Kristoff Felica Fuentes 《Journal of autism and developmental disorders》1991,21(3):281-290
Preschool children with autism and their normally developing peers were compared on the Stanford-Binet IV and Preschool Language Scale before and after 1 school year. Both measures showed that although the children with autism functioned at a lower level than their normally developing peers, the children with autism had narrowed this gap after treatment, making a nearly 19-point increase in IQ and an 8-point gain in language quotient. The IQ measure remained stable for the normally developing peers while their language showed a 7.73-point increase. The data support the notion that young children with autism can make very significant developmental gains.Special thanks to the parents and the children who participated in this study. Thanks also to Michael Alessandri, Jean Burton, David Celiberti, Nancy Gera-Moglia, Anne Nathan, and Lisa Kamean who assisted in the data collection process. We appreciate the cooperation of Alicia MacWright and Leisa Tomchek who taught two of the classes from which participants were drawn. 相似文献
35.
Carl L. Nelson Sandra G. Hickmon Robert A. Skinner 《Journal of orthopaedic research》1997,15(2):249-255
Osteomyelitis was induced in the radius in 77 rabbits and confirmed by histological examination and culture. At 4 weeks, the wounds were debrided and the animals were treated with (a) fatty acid dimersebacic acid beads (a bioerodable composite) impregnated with 20% or (b) 10% gentamicin sulfate, (c) placebo beads and intramuscular gentamicin sulfate. (d) placebo beads alone, or (e) debridement only. After 4 weeks, eradication of infection was determined by histological examination and culture. Osteomyelitis was eradicated in 93% of the animals treated with the beads and 20% gentamicin, in 67% of those treated with the beads arid 10% gentamicin, in 25% of those treated with placebo beads and intramuscular gentamicin, in 7% of those treated with placebo beads alone, and in 12.5% of those treated with debridement only (p values from <0.001 to 0.02). Fatty acid dimer-sehacie acid beads with gentamicin were then implanted in noninfected rabbits, and gentamicin sulfate concentrations in bone, serum, urine, and wound exudate were measured. Gentamicin sulfate was detectable in bone for as long as 8 weeks after implantation. Levels as high as 4,746 g/ml were present in the wound exudate for the first 7 days. Levels in the serum peaked at 1.03 μg/ml. Urine levels peaked at 135 μg/ml. 相似文献
36.
Sandra L Rogers Christopher L Coe Kara Hartke 《The American journal of occupational therapy》2002,56(2):191-201
OBJECTIVE: The purpose of this study was to assess and compare cognitive functioning in adults with unilateral hemispheric injury due to either congenital damage or an ischemic event in young adulthood. METHOD: Adults with cerebral palsy resulting from left hemispheric brain damage were compared with adults who had a unilateral stroke in either the left or the right hemisphere. Our primary interest was to determine the impact on hemispheric dominance as revealed by dichotic listening, a task that assesses the bias for preferential listening and processing of sounds. Performance also was determined on a language-related task (word finding) and a spatial task (dot localization). RESULTS: Scores on the Quick Neurological Screening Test indicated that all participants demonstrated significant neuromotor deficits, whereas scores on the Barthel Index indicated that the participants were functional in basic activities of daily living. On cognitive assessments, healthy control participants demonstrated a pronounced left-hemisphere dominance and right-ear advantage; participants with injury to the left hemisphere showed a strong shift toward a right-hemisphere and left-ear dominance. In particular, injury of congenital origin appeared to foster this neural reorganization and localization of language-related functions into the healthy hemisphere. This shift was associated with a deterioration of performance on both the language and the spatial tasks. CONCLUSION: The importance of appreciating subtle deficits after unilateral injury is important in therapy. The dichotic listening test may provide a simple and useful means for evaluating persistent unilateral brain dysfunction in the clinical setting. 相似文献
37.
One of the advantages of polyurethane foam-covered prostheses has been that in the first 5 to 10 years after their use, the
amount of capsular contraction was found much less than when similar ``slick' prostheses were used. Another advance was their
fixation to the surrounding tissue thus giving a more natural appearance and movement with the muscles when the arms were
moved in any direction. The formation of a thick capsule also acted as a protection against gel granuloma due to rupture of
the prosthesis and has been thought to be a factor in the lower capsule contraction rate. The greatest disadvantage has been
that its removal was extremely difficult and this has continued up until the technique described in this paper has been introduced. 相似文献
38.
39.
Brian F O'Donnell Marcia A Wilt Ann Marie Hake Julie C Stout Sandra C Kirkwood Tatiana Foroud 《Movement disorders》2003,18(9):1027-1034
Disturbances of visual cognition, visuomotor performance, and visual memory have been described frequently in Huntington's disease (HD). Early stage visual abnormalities could contribute to these deficits. We evaluated visual processing in 20 control subjects who were non-gene carriers at risk for HD, nine presymptomatic gene-positive subjects, and eight subjects with a recent diagnosis of Huntington's disease. Visual perceptual tests of contrast sensitivity and motion discrimination were used to probe early stage visual processing. Extraocular movements were evaluated in a neurologic examination, and the Digit Symbol test was used to test visual motor performance. Contrast sensitivity did not differ among the three groups. Motion discrimination was impaired in HD subjects but not in the presymptomatic gene carriers when compared to gene noncarriers. Among gene carriers, impaired motion discrimination performance was associated with poorer Digit Symbol performance and extraocular abnormalities. These findings suggest that the early stages of HD are associated with disturbances of motion perception as well as disruptions of visual motor and ocular motor performance. 相似文献
40.
Sandra Guerra A Teixeira Pinto José Ribeiro José Oliveira José Duarte Jorge Mota 《Revista portuguesa de cardiologia》2003,22(2):167-182
An important aspect of preventive medicine is to identify subjects at risk as soon as possible, so preventive strategies can be introduced at early ages. The justification for this strategy is twofold: firstly, the assumption that children maintain a particular high value of a risk factor for disease throughout life; and secondly, the assumption that lowering the level of the risk factor in early life will have a greater impact on the disease than will risk factor changes in later life. In epidemiology the analysis of such factors over time is referred to as tracking. Tracking analysis has been applied to risk factors for cardiovascular diseases (CVD) in pediatric years. The aims of this study were: I) to analyze the stability of biological risk factors [high blood pressure (BP), high percentage of fat mass (%FM) and high total cholesterol (TC)] and lifestyle risk factors [low physical activity index (PAI)] in isolation; and II) to analyze the stability of zero, one, two or three biological risk factors. There were two evaluations in 692 children and adolescents (325 boys and 367 girls), aged between 8 and 15 years. The quartiles, adjusted for age and gender, were the criterion used to identify subjects with biological risk factors (fourth quartile) and with lifestyle risk factors (first quartile) for CVD. The stability was calculated through the relative frequency of subjects who maintained or changed quartile between the two evaluations. There is stability for biological risk factors as well as for behavioral and/or lifestyle risk factors. However, the highest stability is seen in biological risk factors. 相似文献