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81.
Changes in temporal gait characteristics and pressure distribution for bare feet versus various heel heights 总被引:8,自引:0,他引:8
The purpose of this study was to identify changes in temporal gait characteristics and pressure generation across the sole of the foot due to various heel heights in women's dress pumps. Thirty female subjects, aged 18-30 years, volunteered to participate. Subjects were required to have normal gait and to wear comfortably either size 7 or size 9 shoes. Subjects were tested initially in bare feet using electrodynography (Langer Biomechanics Group, 21 East Industry Court, Deer Park, NY 11729-9986) (EDG) at a cadence of ~100 steps/min set by metronome. EDG trials with 4 pairs of shoes were then performed in random order. Shoes were women's dress pumps identical except for heel height. Heel heights were 1.75, 3.12, 5.72 and 8.74 cm. Data were collected over ~ 30 steps and averaged over this period. Data were analyzed using a one-way ANOVA, and changes were only considered significant if the ANOVA identified significant variations bilaterally. Considering temporal gait variables, we concluded that: (1) stance phase was shortened in shoes vs. bare feet but was unaffected by heel height, (2) the percentage of stance spent in weight bearing on the lateral and medial calcaneus decreased above a 3.12 cm heel height, (3) the percentage of stance spent in weight bearing on the first and second metatarsal heads increased in shoes vs. bare feet but was unaffected by heel height, (4) the percentage of stance spent in weight bearing on the fifth metatarsal was less in the 8.74 cm heel than in any other shoe or in bare feet. With regard to pressure variables, we found that: (1) peak pressure under the fifth metatarsal head was inversely related to heel height, (2) pressure under the third metatarsal head peaked earliest in heels greater than 5.72 cm high, and (3) pressure under the medial calcaneus peaked latest in heels greater than 5.72 cm high. 相似文献
82.
83.
Using a simplified procedure, we have extracted DNA from unstained paraffin sections of needle biopsies of kidney and liver transplants and identified the presence of CMV using the polymerase chain reaction. This method utilizes oligonucleotide primers for two genes shown to be specific for cytomegalovirus (CMV) as well as an internal control gene (hemoglobin) in a single reaction. Utilizing nested PCR amplification with agarose gel electrophoresis, CMV can be detected without radioisotopes to a level of sensitivity equivalent to one one-hundredth of a cytomegalic virocyte per cm2 of a 3-microM paraffin section. This method is applicable to situations where only scarce paraffin-embedded tissue is available. 相似文献
84.
85.
Health effects of passive smoking. 1. Parental smoking and lower respiratory illness in infancy and early childhood 总被引:15,自引:9,他引:6
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BACKGROUND: A systematic quantitative review was conducted of evidence relating parental smoking to acute lower respiratory illness in the first three years of life. METHODS: Fifty relevant publications were identified after consideration of 692 articles selected by electronic search of the Embase and Medline databases using keywords relevant to passive smoking in children. The search, completed in April 1997, identified 24 studies ascertaining illnesses in a community setting, including five surveys of schoolchildren with retrospective ascertainment of early chest illness, and 17 studies of admissions to hospital for lower respiratory illness in early life. Thirty eight studies were included in a quantitative overview using random effects modelling to derive pooled odds ratios. RESULTS: The results of community and hospital studies are broadly consistent, with only one publication reporting a reduced risk among children of smokers. The pooled odds ratios were 1.57 (95% CI 1.42 to 1.74) for smoking by either parent and 1.72 (95% CI 1.55 to 1.91) for maternal smoking. There is a significantly increased risk of early chest illness associated with smoking by other household members in families where the mother does not smoke (1.29, 95% CI 1.16 to 1.44). The associations with parental smoking are robust to adjustment for confounding factors, and show evidence of a dose-response relationship in most studies in which this has been investigated. CONCLUSIONS: The relationship between parental smoking and acute lower respiratory illness in infancy is very likely to be causal. Although it is impossible to distinguish the independent contributions of prenatal and postnatal maternal smoking, the increased risk associated with smoking by other household members suggests that exposure to environmental tobacco smoke after birth is a cause of acute chest illness in young children.
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86.
Passive smoking and sudden infant death syndrome: review of the epidemiological evidence 总被引:5,自引:1,他引:4
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BACKGROUND: This paper provides a systematic, quantitative review of the epidemiological evidence relating parental smoking and sudden infant death. METHODS: Thirty two relevant publications were identified after consideration of 692 articles selected by electronic search of the Embase and Medline databases using keywords and Mesh headings relevant to passive smoking in children. Eleven further articles were identified from reviews and by talking to authors. The search was completed in April 1997 and identified 39 studies. RESULTS: The unadjusted pooled odds ratio for prenatal maternal smoking was 2.77 (95% CI 2.45 to 3.13). After adjustment for a variety of confounders the pooled odds ratio was reduced to 2.08 (95% CI 1.83 to 2.38) and was similar in cohort and case-control studies. Four studies reported on maternal postnatal smoking after controlling for prenatal maternal smoking (pooled odds ratio 1.94 (95% CI 1.55 to 2.43)). Of three studies reporting on the risk of paternal smoking where the mother was a non-smoker, two found significant effects while one found no effect. Dose-response relationships with both prenatal and postnatal maternal smoking were present in most studies which provided data. CONCLUSIONS: Maternal smoking doubles the risk of sudden infant death syndrome. The relationship is almost certainly causal. There is good evidence that postnatal exposure to environmental tobacco smoke from both mother and father are important. Because prenatal smoking is almost invariably associated with postnatal smoking, the role of prenatal smoking per se will be difficult to resolve using epidemiological studies.
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87.
The measurement of patient satisfaction 总被引:1,自引:0,他引:1
88.
Robert T. Cook Thomas J. Waldschmidt Zuhair K. Ballas Brian L. Cook Brenda M. Booth Barbara C. Stewart Michael J. Garvey 《Alcoholism, clinical and experimental research》1994,18(1):71-80
Alcoholics admitted to the hospital solely for detoxication have been studied by flow cytometry to evaluate changes in the surface markers of peripheral blood leukocytes. As we have shown previously, such patients have an elevated percentage of CD8hl lymphocytes that are HLA DR+; we now demonstrate that they also have striking alterations in the quantitative relationships of the fine T-cell subsets. Both CD4+ and CD8hl lymphocytes have a sharply reduced percentage of the l -selectin+ CD45RA+ subset, increased percentages of the CD45RA-subsets, and several other fine subset alterations. The fine subset profile suggests, according to current correlations of phenotype and function, that both CD4+ suppressor inducer and CD4-dependent CD8+ suppressor effector cells are reduced, whereas other subsets, including CD8+ CTL or their precursors, are increased in relative percentages. Some of the phenotypic changes are reversible over the several days following withdrawal. In other results, the percentage of CD8hl lymphocytes expressing CD11b (β-integrin) is shown to be reciprocal with the percentage expressing l -selectin both in normals and alcoholics. However, the regression function of CD11b vs. l -selectin on CD8hl cells is different for the alcoholics than for the normals, indicating an abnormality in the regulation of the expression of these two adhesion markers. Taken together, this abnormality of adhesion molecules and the fine subset alterations previously described indicate widespread changes in the peripheral lymphocytes of currently drinking alcoholics. These changes suggest functional deficiencies that may include alterations of lymphocyte traffic and other adhesion-dependent functions, and a shift in the balance of regulatory interactions. 相似文献
89.
J. Davignon R. Dufour M. Roy C. Bétard Y. Ma S. Ouellette L. Boulet S. Lussier-Cacan 《European journal of epidemiology》1992,8(1):10-17
Of 163 individuals with a diagnosis of heterozygous familial hypercholesterolemia (FH), only one subject was found to be positive for familial defective apo B-100 (FDB). The eight-member kindred ascertained through this subject who presented with both a clinical phenotype of FH and the FDB apo B-100 (Arg3500→-Gln) mutation was studied. Plasma lipid and lipoprotein profiles, apo E phenotypes, apo B gene markers at the 3′ hypervariable region and LDL-receptor haplotypes (ApaLI, PvuII, NcoI), were determined, together with LDL-receptor activity on freshly isolated blood lymphocytes. The FDB mutation, present in four relatives, was associated with three different phenotypes: FH and severe hypercholesterolemia, moderate hypercholesterolemia and normolipidemia. The FH phenotype occurred in the absence of any functional LDL-receptor defect. In homozygotes for the absence of the PvuII cutting site who had the apo B mutation, LDL-cholesterol levels were low in the presence of the apo E3/2 phenotype and high in the presence of the apo E4/4 phenotype. None of the major known environmental influences accounted for the wide range of variation in LDL-cholesterol among the affected members. Further observations in the spouse and offspring of the normolipidemic FDB subject confirmed the association of apo E4, the FDB mutation and the PvuH(-/-) genotype with high cholesterol levels. It is concluded that the phenotypic expression of the FDB mutation may vary widely as a function of the genetic environment within a family. The presence of phenotypic heterogeneity among individuals with the same apo B mutation may result from epistatic interaction of the apo B locus with genetic factors regulating cholesterol homeostasis, including possible involvement of the apo E and the LDL-receptor gene loci. This study also confirms that the clinical diagnosis of FH is not necessarily associated with an LDL-receptor defect. 相似文献
90.
Job ending among youth and adults with severe mental illness 总被引:1,自引:0,他引:1
This study examined job leaving over a 36-month period among 326 persons (74 youth and 252 adults) with severe mental illness who were participating in an urban vocational rehabilitation program. Data from 627 job endings indicated that younger clients displayed job-ending patterns that were different in some aspects from such patterns for nondisabled youth (such as displaying a lower average job tenure) yet similar to job-ending patterns for nonhandicapped youth in other ways (such as displaying a high frequency of job changing). Youth and their adult counterparts with mental illness displayed similar tenure on agency-sponsored placements but significantly different tenure on independent jobs. While adults held their independent jobs for an average of seven months, youth averaged only three months at competitive employment. Youth also were significantly more likely than adults to be fired from both placements and independent jobs. These findings and others are discussed in terms of their implications for development of public policy and service delivery models for providing on-going job support to youth and adults with severe psychiatric disabilities. 相似文献