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31.
INTRODUCTION: Falls are a major cause of morbidity and mortality in children, but are also reported falsely in child abuse. Therefore, it is of interest to understand those factors which may lead to a higher likelihood of injury in a feet-first freefall. METHODS: We used laboratory freefall experiments and a 3-year-old Hybrid III anthropomorphic test dummy (ATD) to assess head and femur injury risk. Wet and dry linoleum impact surfaces were used from three fall heights: 22, 35 and 47 in. RESULTS: For a given fall height, dry surfaces were associated with higher head injury criteria (HIC) values than wet surfaces. Changes in fall height 22-47 in. did not significantly affect HIC values for falls onto either surface. Generally, compressive and bending femur loading increased significantly for wet as compared to dry linoleum. CONCLUSIONS: In simulated feet first freefall experiments up to 47 in. using a 3-year-old test dummy, a low risk of contact type head injury and femur fracture was found. However, both fall height and surface conditions influenced femur loading and head injury measures. Future efforts should explore the risk of head injury associated with angular acceleration in freefalls.  相似文献   
32.
Use of R-Mix Fresh Cells has been shown to be a rapid and sensitive method for the detection and identification of respiratory viruses. We prospectively evaluated the impact of incorporation of R-Mix shell vials on the sensitivity and time to detection of seven respiratory viruses recovered in a comprehensive culture during the course of an entire respiratory season in a high-volume clinical laboratory. In this study, R-Mix shell vials were used as part of the culture of 3803 respiratory specimens. A total of 428 respiratory viruses were recovered. Staining of R-Mix vials after overnight incubation allowed initial detection of 274 of 279 influenza viruses, 33 of 38 parainfluenza viruses, 35 of 51 adenoviruses, and 52 of 60 respiratory syncytial viruses (RSVs). The time to reporting of all positive cultures after in-lab specimen receipt was 2.9 days on average and those initially detected in R-Mix cells were reported in 2.3 days on average. A combination of direct fluorescent-antibody (DFA) staining and virus culture was performed on a subset of 711 respiratory specimens. Of 152 viruses identified, 57 were observed only with DFA testing (55 RSV and 2 influenza A viruses) and 31 were recovered only in cell culture. After overnight incubation, R-Mix cells detected 87.1% of respiratory viruses not observed by DFA testing and 96.9% of viruses positive by both methods. The sensitivities of DFA testing and R-Mix cells for identification of influenza viruses were 70.5% and 96.7%, respectively. The R-Mix method detected influenza virus in 18 samples that were negative by DFA testing.  相似文献   
33.
T cell receptors for the Fc portion of the various isotypes of mouse immunoglobulins (FcR) were examined by rosette formation, using as indicator cells erythrocytes coated with monoclonal antibodies of all known isotypes of serum immunoglobulins. Three populations of mouse T cells were studied: normal thymocytes, activated T cells (ATC), generated by educating thymocytes in lethally irradiated allogeneic hosts, and hybridoma T cells, derived from somatic hybridization of ATC with the FcR-negative thymoma BW.5147. We found that many different FcR could be distinguished by their specificity for a single isotype or for a combination of several isotypes; ATC and hybridoma T cells expressed several such receptors that, at least in cloned cells, could be demonstrated to be borne by individual cells; hybridoma T cells of independent origin bore indistinguishable receptors whereas ATC expressed markedly different FcR and upon overnight incubation at 37 degrees C, immunoglobulins were found to bind onto the cell surface, even though no corresponding constitutive FcR was detected. The same was observed with hybridoma T cells and with thymocytes. It follows that a single T cell can express several FcR. Altogether, these FcR are capable of binding all known isotypes of serum immunoglobulins. They differ from one T cell to another.  相似文献   
34.
Mammalian sex chromosomes evolved from an ancient autosomal pair. Mapping of human X- and Y-borne genes in distantly related mammals and non-mammalian vertebrates has proved valuable to help deduce the evolution of this unique part of the genome. The platypus, a monotreme mammal distantly related to eutherians and marsupials, has an extraordinary sex chromosome system comprising five X and five Y chromosomes that form a translocation chain at male meiosis. The largest X chromosome (X1), which lies at one end of the chain, has considerable homology to the human X. Using comparative mapping and the emerging chicken database, we demonstrate that part of the therian X chromosome, previously thought to be conserved across all mammals, was lost from the platypus X1 to an autosome. This region included genes flanking the XIST locus, and also genes with Y-linked homologues that are important to male reproduction in therians. Since these genes lie on the X in marsupials and eutherians, and also on the homologous region of chicken chromosome 4, this represents a loss from the monotreme X rather than an additional evolutionary stratum of the human X.  相似文献   
35.
36.
Maternal and Child Health Journal - In the US, approximately 8% of pregnant women smoke, and 5–11.9% currently use ENDS products. The health effects of ENDS use are debated; however, most...  相似文献   
37.
IntroductionSemen induces mucosal changes in the female reproductive tract to improve pregnancy outcomes. Since semen‐induced alterations are likely short‐lived and genital inflammation is linked to HIV acquisition in women, we investigated the contribution of recent semen exposure on biomarkers of genital inflammation in women at high HIV risk and the persistence of these associations.MethodsWe assessed stored genital specimens from 152 HIV‐negative KwaZulu‐Natal women who participated in the CAPRISA 008 trial between November 2012 and October 2014. During the two‐year study period, 651 vaginal specimens were collected biannually (mean five samples per woman). Cervicovaginal lavage (CVL) was screened for prostate‐specific antigen (PSA) by ELISA, whereas Y‐chromosome DNA (YcDNA) detection and quantification were conducted by RT‐PCR, representing semen exposure within 48 hours (PSA+YcDNA+) and semen exposure within three to fifteen days (PSA−YcDNA+). Soluble protein concentrations were measured in CVLs by multiplexed ELISA. T‐cell frequencies were assessed in cytobrushes by flow‐cytometry, and vulvovaginal swabs were used to detect common vaginal microbes by PCR. Linear mixed models adjusting for factors associated with genital inflammation and HIV risk were used to assess the impact of semen exposure on biomarkers of inflammation over multiple visits.ResultsHere, 19% (125/651) of CVLs were PSA+YcDNA+, 14% (93/651) were PSA−YcDNA+ and 67% (433/651) were PSA−YcDNA−. Semen exposure was associated with how often women saw their partners, the frequency of vaginal sex in the past month, HSV‐2 antibody detection, current gonorrhoea infection and Nugent Score. Both PSA detection (PSA+YcDNA+) and higher cervicovaginal YcDNA concentrations predicted increases in several cytokines, barrier‐related proteins (MMP‐2, TIMP‐1 and TIMP‐4) and activated CD4+CCR5+HLA‐DR+ T cells (β = 0.050; CI 0.001 to 0.098; p = 0.046) and CD4+HLA‐DR+ T cells (β = 0.177; CI 0.016 to 0.339; p = 0.032) respectively. PSA detection was specifically associated with raised pro‐inflammatory cytokines (including IL‐6, TNF‐α, IP‐10 and RANTES), and with the detection of BVAB2 (OR = 1.755; CI 1.116 to 2.760; p = 0.015), P. bivia (OR = 1.886; CI 1.102 to 3.228; p = 0.021) and Gardnerella vaginalis (OR = 1.815; CI 1.093 to 3.015; p = 0.021).ConclusionsMore recent semen exposure was associated with raised levels of inflammatory biomarkers and the detection of BV‐associated microbes, which declined by three to fifteen days of post‐exposure. Although transient, semen‐induced alterations may have implications for HIV susceptibility in women.  相似文献   
38.
Regulation of -adrenoceptor (-ar) subtypes and transregulation of muscarinic cholinoceptors (mAchr) was examined in regions of rat heart after chronic infusion of (–)-isoprenaline (450 /kg per hour) for 14 days. Following (–)-isoprenaline infusion systolic blood pressure was reduced for 10 days but then gradually returned to control levels, whereas heart rate was increased for 7 days before declining to a level significantly above control. Heart weight to body weight ratio was increased in (–)-isoprenaline treated rats. -ar subtype densities were measured by quantitative autoradiography with [125I]-cyanopindolol (CYP) in sinoatrial node (SA), atrioventricular node (AV), bundle of His (BH), left (LB) and right (RB) bundle branches, interventricular (IVS) and interatrial (IAS) septa, right atria (RA), apex (AX) and mitral valve (MV). 1-ars were reduced by 59.1–74.2% in the AV conducting regions, 53.4% in the SA node and 43.3–53.4% in myocardial areas. 2-ars were markedly reduced in myocardial regions (93.2–98.5%) and in pacemaker and conducting regions (87.7–97.8%). No changes in mAchr densities measured using [3H]-N-methyl scopolamine (NMS) occurred in the AV node, BH, LB, RB, IVS and IAS following (–)-isoprenaline infusion.Densities of 1- and 2-ars and mAchrs were also measured in ventricular homogenates from control and (–)-isoprenaline treated animals. -ar levels were significantly reduced (P < 0.05) in treated animals and the ratio of 1- to 2-ars increased after treatment. mAchr density in ventricular homogenates measured using either [3H]-NMS or [3H]-quinuclidinyl [phenyl-4-3H]benzilate (QNB) was unchanged. Homogenates of left and right ventricle also showed no change using [3H]-NMS.Organ bath studies were used to investigate the effect of (–)-isoprenaline infusion on negative inotropic and chronotropic effects of the non-selective muscarinic receptor agonist bethanechol in left and right atria, respectively. Lower concentrations of bethanechol (3 × 10–10 to 10–6 M) produced a negative inotropic response in isolated electrically driven left atria from (–)-isoprenaline treated rats, but not from control rats, with the slope of the curves being significantly different between groups (ANCOVA, P = 0.037). At concentrations of bethanechol from 10–6 to 3 × 10–4 M the negative inotropic response was not changed between (–)-isoprenaline treated and control animals. Bethanechol also produced a negative chronotropic response at lower concentrations (10–10 to 10–6 M) in (–)-isoprenaline treated rats, but not in controls. A second, steeper phase of the negative chronotropic response occurred at concentrations of bethanechol greater than 10–6 M and was also seen in control rats.Expression of M2 (cardiac) mAchrs (m2Achr) in left and right ventricular tissues measured using a quantitative non-competitive polymerase chain reaction (PCR) assay showed a significant (P = 0.001) 28.5% increase in expression in left ventricle and a significant (P = 0.003) 21.5% decrease in expression in right ventricle after (–)-isoprenaline treatment, compared to controls. There was no significant difference in total ventricular m2Achr expression between the two groups of rats. The results suggest that chronic -ar stimulation down-regulates both 1- and 2-ars, and appears to differentially transregulate m2Achr expression, but not mAchr protein. Following (–)-isoprenaline infusion, muscarinic receptor mediated responses were sensitised, with no change in receptor densities, suggesting changes occur in the cell signalling system beyond the level of the receptor.  相似文献   
39.
This is the fifth in a series of articles highlighting the relevance of sociological theory to pharmacy practice research. The article provides an introduction to feminist theory and research as applied to health, illness and health care. The aim is to clarify the contribution made by feminist theory in developing useful conceptual tools and theories in two major areas: the specific experiences of women's health and understanding the role of women as providers of health care. We seek to contribute to a research agenda, informed by feminist thinking, for pharmacy practice. The focus of this article is on feminist theory as developed in the West, with particular emphasis on issues of concern for pharmacy practice research. We begin with a discussion of the historical context of feminism, including the women's movement and the women and health movement. This is followed by an overview of selected feminist theories. Feminist perspectives on the experience of health and illness are discussed in more detail, including issues of reproductive technologies, gender, health and morbidity; gender differences in the medical encounter; and finally the relevance of a feminist approach to pharmacy practice research, including research questions that are relevant today.  相似文献   
40.
The relationship between coercion strategies used by perpetrators of childhood sexual abuse (CSA) and elevations of CSA survivors on the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) was investigated. Participants were 151 women survivors of CSA in outpatient treatment at a university-based community mental health center. Scores on the MMPI-2 clinical scales and the Keane posttraumatic stress disorder (PTSD) scale were examined. Main effects were found for promised or received rewards on several clinical scales and the PTSD scale of the MMPI-2, independent of the presence of force. Specifically, the presence of such rewards was associated with significantly higher levels of symptomatology on Paranoia (Pa), Psychasthenia (Pt), Schizophrenia (Sc), and PTSD (Pk). There were no main or interaction effects noted for the presence of actual or threatened force on any of the scales.  相似文献   
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