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11.
Mechanisms of exercise-induced asthma   总被引:2,自引:0,他引:2  
In a previous review in this journal McFadden eloquently presented the findings which led him and his colleagues to propose that respiratory heat loss and the subsequent cooling of the airways are the initial reaction sequence leading to airway obstruction in hyperventilation and exercise-induced asthma [62]. He further concluded that: “Exercise per se is not essential and serves only as means to increase ventilation”. Our interpretation of currently available data has led us to conclude that while respiratory heat loss may play an important permissive role in initiating the bronchoconstriction which follows exercise, the weight of evidence indicates that exercise per se serves as the trigger mechanism and is not just a tool to increase ventilation. Moreover, we believe that the role of exercise in releasing chemical mediators has been established, although pathways by which the airway smooth muscle is affected are still uncertain.  相似文献   
12.
Treatment of mouse-spleen cells with galactose oxidase (EC 1.1.3.9) after incubation with neuraminidase (EC 3.2.1.18) induced extensive blastogenesis. Treatment of the cells with galactose oxidase before incubation with neuraminidase had very little stimulatory effect. Either of these enzymes alone had practically no effect on the cells. The lymphocyte transformation induced by galactose oxidase in neuraminidase-treated cells was decreased upon reacting the cells with borohydride or hydroxylamine, whereas treatment with these compounds did not affect transformation of cells by concanavalin A. It is suggested that galactosyl residues exposed by the action of neuraminidase on the cell membrane are oxidized by galactose oxidase, and the aldehyde moiety thus formed is involved in the induction of blastogenesis.  相似文献   
13.
Outcomes of nonmyeloablative (NMA) haploidentical (haplo) blood or marrow transplant (BMT) with post-transplantation cyclophosphamide (PTCy) using non–first-degree relatives are unknown. We evaluated 33 consecutive adult patients (median age, 56 years) with hematologic malignancies who underwent NMA haplo T cell–replete BMT with PTCy at Johns Hopkins using second- or third-degree related donors. Donors consisted of 10 nieces (30%), 9 nephews (27%), 7 first cousins (21%), 5 grandchildren (15%), and 2 uncles (6%). Thirty-one patients (94%) reached full donor chimerism by day 60. The estimated cumulative incidence (CuI) of grades II to IV acute graft-versus-host disease (aGVHD) at day 180 was 24% (90% confidence interval [CI], 9% to 38%). Only 1 patient experienced grades III to IV aGVHD. At 1 year the CuI of chronic GVHD was 10% (90% CI, 0% to 21%). The CuI of nonrelapse mortality at 1 year was 5% (90% CI, 0% to 14%). At 1 year the probability of relapse was 31% (90% CI, 12% to 49%), progression-free survival 64% (90% CI, 48% to 86%), and overall survival 95% (90% CI, 87% to 100%). The 1-year probability of GVHD-free, relapse-free survival was 57% (90% CI, 41% to 79%). NMA haplo BMT with PTCy from non–first-degree relatives is an acceptably safe and effective alternative donor platform, with results similar to those seen with first-degree relatives.  相似文献   
14.
The aim of the study was to compare the prevalence of cervical muscle pain (CMP) and myogenic temporomandibular disorders (MFP) among female dentists, high‐tech workers, and a group of subjects employed in other occupations; to investigate the associations among CMP, MFP, and bruxism in those groups; and to evaluate the influence of work‐related stress on MFP and CMP. Evaluation was based on clinical examinations of MFP and CMP and self‐reported questionnaires concerning pain and stress. The diagnosis of sleep bruxism was adapted using the validated diagnostic criteria of the American Academy of Sleep Medicine (International Classification of Sleep Disorders (ICSD‐2), 2005, Westchester, IL), whilst the diagnosis of awake bruxism was made on the basis of a questionnaire. The odds of a subject with MFP experiencing concurrent CMP or bruxism (sleep and/or awake) ranged from 2.603 to 3.077. These results suggest that high‐tech workers and dentists are at greater risk for developing temporomandibular disorders (TMDs) and CMP when compared with general occupation workers, as defined in this study. Furthermore, the associations shown here between TMDs and CMP highlight the importance of palpating neck musculature as part of any routine examination of TMD.  相似文献   
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We studied associations between perceived adequacy of live donor kidney transplant (LDKT) information or knowledge with pursuit of LDKT or receipt of live donor inquiries among 300 African American kidney transplant candidates. Participants reported via questionnaire how informed or knowledgeable they felt regarding LDKT. Participants also reported their pursuit of LDKT, categorized as “low” (no discussion with family or friends about LDKT and no identified donor), “intermediate” (discussed LDKT with family but no identified donor) or “high” (discussed LDKT with family and identified a potential donor). We reviewed participants' electronic health records to identify potential donors' transplant center inquiries on participants' behalves. A minority of participants reported they felt “very” or “extremely” well informed about LDKT (39%) or had “a great deal” of LDKT knowledge (38%). Participants perceiving themselves as “very” or “extremely” (vs “not” or “slightly”) well informed about LDKT had statistically significantly greater odds of intermediate or high (vs low) pursuit of LDKT (odds ratio [95% confidence interval] 2.71 [1.02-7.17]). Perceived LDKT knowledge was not associated with pursuit of LDKT. Neither perceived information adequacy nor knowledge was associated with living donor inquiries. Efforts to better understand the role of education in the pursuit of LDKT among African American transplant candidates are needed.  相似文献   
18.
The purpose of this study was to test a model of exposure to environmental tobacco smoke (ETS) in military women and their children. The convenience sample consisted of 238 women, 81 smokers and 157 nonsmokers, with a mean age of 37 years (SD = 9.9). Participants were either on active duty or were reservists and/or military dependents. Model constructs, some of which were adapted from the transtheoretical model of behavior change, measured personal and situational factors, pros and cons of ETS exposure, self-efficacy to resist ETS, mother's expectation for child's ETS exposure, and mother's self-efficacy to reduce child's ETS exposure. The mediating variable was the mother's daily ETS exposure, and the outcome variable was the child's daily ETS exposure. The trimmed model showed that 32% of the variance in mother's daily exposure (mediating variable) was accounted for by living with a smoker, having high ETS "pros" (as opposed to ETS "cons"), having less self-efficacy to resist ETS, and having greater self-efficacy to reduce the child's exposure. There was a significant, positive relationship (r = 0.51, p = 0.01) between the mother's and child's daily ETS exposure (outcome variable).  相似文献   
19.
The purpose of this study was to determine the extent to which selected demographic characteristics, definition of health, perceived health status, perceived self-efficacy, and resources are related to the health promoting behaviors of active-duty women with children and to describe qualitatively the experience of being an active-duty mother. Grounded in Pender's (1996) Health Promotion Model, this study used methodological triangulation to test a hypothesized model. A sample of 141 active-duty women with children using military health services participated. Resource availability and commitment were key components of being successful at balancing home and work demands.  相似文献   
20.
Using cDNA microarrays, we identified StarD4 as a gene whose expression decreased more than 2-fold in the livers of mice fed a high-cholesterol diet. StarD4 expression in cultured 3T3 cells was also sterol-regulated, and known sterol regulatory element binding protein (SREBP)-target genes showed coordinate regulation. The closest homologues to StarD4 were two other StAR-related lipid transfer (START) proteins named StarD5 and StarD6. StarD4, StarD5, and StarD6 are 205- to 233-aa proteins consisting almost entirely of START domains. These three constitute a subfamily among START proteins, sharing approximately 30% amino acid identity with one another, approximately 20% identity with the cholesterol-binding START domains of StAR and MLN64, and less than 15% identity with phosphatidylcholine transfer protein (PCTP) and other START domains. StarD4 and StarD5 were expressed in most tissues, with highest levels in liver and kidney, whereas StarD6 was expressed exclusively in the testis. In contrast to StarD4, expression of StarD5 and MLN64 was not sterol-regulated. StarD4, StarD5, and StarD6 may be involved in the intracellular transport of sterols or other lipids.  相似文献   
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