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11.
The primary purpose of this study was to determine if the aerobic demand for production of specified power outputs is altered by distribution of work between the arms and legs compared with when all the work is performed by the legs. Because of the important exercise training implications, a secondary purpose of this study was to determine if the exercising muscle mass affects the cardiorespiratory demands at specified rating of perceived exertion (RPE) levels and blood lactate concentrations. Nine healthy adults completed leg cycling and combined arm and leg exercise on an Airdyne using a discontinuous protocol. Repeated measures ANOVA revealed that oxygen uptake for the combined arm and leg exercise averaged 0.04 l·min−1 greater (p<0.05) than for leg cycling at the same external power outputs. However, RPE levels at specified power outputs were lower (p<0.05) with combined arm and leg exercise than leg cycling. At specified RPE levels and blood lactate concentrations, oxygen uptake and heart rate values were higher (p<0.05) for combined arm and leg exercise than leg cycling. From these findings we conclude that: (1) the addition of arm exercise to leg cycling results in a reduction in RPE, but a minimal increase in oxygen consumption to perform a given power output, and (2) if training intensity is established by RPE or blood lactate concentration, use of a muscle mass larger than that used in leg cycling should allow a greater cardiorespiratory training effect.  相似文献   
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BACKGROUND: There is limited information about respiratory syncytial virus (RSV) in high-risk children from developing countries or on the genotype characterisation of the circulating virus. OBJECTIVE: To define the proportion of children with RSV associated lower respiratory tract infections (LRTI) that had risk factors for severe disease and to genotype the circulating RSV strains across the country. STUDY DESIGN: A prospective study was performed in four distinct regions. During April 2000-December 2000 (period 1), all children, with LRTI or without underlying high risk factors for severe RSV disease were enrolled. During January to September 2001 (period 2), only children with LRTI with underlying high risk factors were enrolled. Nasopharyngeal aspirates were evaluated for RSV infection using an ELISA test. RSV isolates were also subtyped and genotyped. RESULTS: Fifty three (24%) of 220 children enrolled during period 1 had risk factors for severe RSV disease; in addition to which a further 38 high-risk children were enrolled during 2001. RSV was isolated from 16 (30%) of 53 and 37 (22%) of 167 high-risk and non-high risk children, respectively, P=0.31. High-risk children were more likely to require intensive unit care (25 vs. 2.7%, P=0.02) and were also more likely to be hospitalised for a longer duration (median 7 vs. 5 days, P=0.06) than non high-risk infants. Overall (periods 1 and 2), RSV was isolated from 34 (37.4%) of the 91 high-risk infants enrolled. Among high-risk children, those from whom RSV was isolated were more likely to require hospitalisation (73.5 vs. 54.4%, P=0.07) and admission to an intensive care unit (14.7 vs. 1.8%, P=0.03) than those from whom RSV was not isolated. Of 40 isolates subtyped during period one, 92.5% were subtype A. Further, 27 (83.3%) of 30 subtype A isolates genotyped during period 1 clustered with GA2. CONCLUSION: RSV is an important cause of LRTI among high-risk infants in a developing country such as South Africa. For the season in question, the genotype that was dominant in Johannesburg was isolated throughout the country, suggesting that successful genotypes may have the ability to spread nationwide.  相似文献   
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ObjectivePatients with rheumatic diseases often have multiple comorbidities which may impact well‐being leading to high psychosocial complexity. This scoping review was undertaken to identify complexity measures/tools used in rheumatology that could help in planning and coordinating care.MethodsMEDLINE, EMBASE and CINAHL were searched from database inception to 14 December 2019 using keywords and Medical Subject Headings for “care coordination”, “complexity” and selected rheumatic diseases and known complexity measures/tools. Articles describing the development or use of complexity measures/tools in patients with adult rheumatologic diagnoses were included regardless of study design. Included articles were evaluated for risk of bias where applicable.ResultsThe search yielded 407 articles, 37 underwent full‐text review and 2 were identified during a hand search with 9 included articles. Only 2 complexity tools used in populations of adult patients with rheumatic disease were identified: the SLENQ and the INTERMED. The SLENQ is a 97‐item patient needs questionnaire developed for patients with systemic lupus (n = 1 study describing tool development) and applied in 5 cross‐sectional studies. Three studies (a practice article, trial and a cross‐sectional study) applied the INTERMED, a clinical interview to ascertain complexity and support coordinated care, in patients with rheumatologic diagnoses.ConclusionsThere is limited information on the use of patient complexity measures/tools in rheumatology. Such tools could be applied to coordinate multidisciplinary care and improve patient experience and outcomes.Patient contributionThis scoping review will be presented to patient research partners involved in co‐designing a future study on patient complexity in rheumatic disease.  相似文献   
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Quality of Life Research - To examine agreement between pediatric burn survivor self- and caregiver proxy-report on multiple PROMIS domains and examine factors associated with differences between...  相似文献   
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Altered adhesion plaques have been observed in transformed cell lines and are associated with enhanced metastatic potential. The prototypical adhesion plaque is formed by 51 fibronectin receptors (FnRs) interacting with the cellular actin network. We have found differences in the actin networks of noninvasive (FTC-133) and invasive (FTC-236, FTC-238) clones of a human follicular thyroid cancer cell line. Furthermore, thyroid-stimulating hormone (TSH) induces stress fibers in FTC-133. In order to investigate differences in adhesion plaques, expression of fibronectin (FN) and its receptor by these cells was analyzed. For these studies FTC-133, FTC-236, and FTC-238 were cultured in serum-depleted DME-H21 medium for 24 hours before the addition of TSH 30 mU/ml. No quantitative differences were noted in FN expression on Western blot in either the conditioned medium or cellular extracts. Western blots and immunohistochemical studies indicated that TSH induced secretion of FN only in FTC-133. Flow cytometry with an 5 antibody demonstrated a 52% and 45% reduction (p<0.01) in expression of FnR by FTC-236 and FTC-238, respectively, compared to FTC-133; this finding was supported by immunohistochemistry results. TSH treatment did not alter FnR expression. From these studies, we conclude that invasive clones of FTC decrease their expression of FnRs without changing their expression of FN. Furthermore, TSH treatment may promote FN secretion by FTC-133, although it does not seem to affect FnR or absolute FN expression. The diminished expression of FnR adhesion plaques may enhance metastatic potential in some follicular thyroid cancers.
Resumen Se han observado placas adhesivas alteradas en líneas celulares transformadas en asociación con un potencial metastásico incrementado. La prototípica placa adhesiva se forma por la interacción de receptores 5-1 con la trama celular de actina. Hemos encontrado diferencias en las tramas de actina en clones no invasivos (FTC-133) e invasivos (FTC-236, FTC-238) de una línea celular de cáncer folicular de tiroides.Además, la TSH induce líneas de estrés en FTC-133. Con el objeto de investigar las diferencias en las placas adhesivas, se hizo el análisis de la expresión de fibronectina (FN) y sus receptores en tales células.Para estos estudios se hizo el cultivo de FTC-133, FTC-236 y FTC-238, en sueros depletados de DME-H21 por 24 horas anteriores a la adición de 30 mU/ml TSH por 24 horas. No se observaron diferencias cuantitativas en la expresion de FN o en el Western blot ni en los medios condicionados ni en los extractos celulares. Los Western blots y los estudios inmunohistoquímicos indicaron que la TSH induce la secreción de FN sólo en FTC-133. La citometría de flujo con un anticuerpo 5 demostró una reducción de 52% y 45% (p<0.01) en la expresión de FnR por FTC-236 y FT-238, respectivamente, en comparación con FTC-133; este hallazgo fue verificado por inmuno-histoquímica. El tratamiento con TSH no alteró la expresón FnR. Con base en estos estudios, es nuestra conclusión que los clones invasivos de FTC disminuyen la expresión de FnR sin cambiar su expresión de FN. Además, el tratamiento con TSH puede promover la secreciòn de FN por FTC-133, aunque no parece afectar la expresión de FnR o la expresión absoluta de FN. Esta expresión disminuída de las placas adhesivas FnR puede incrementar el potencial metastásico en algunos cánceres foliculares de tiroides.

Résumé On a observé des altérations des plaques d'adhésion dans certaines lignées cellulaires transformées, et celles-ci semblent être associées à un potentiel métastatique augmenté. La plaque d'adhésion prototypique est formée par des récepteurs 51 de fibronectine (FnR) qui agissent sur le réseau cellulaire d'actine. Nous avons trouvé une différence entre les réseaux d'actine des clones noninvasifs (FTC-133) et invasifs (FTC-236, FTC-238) des lignées cellulaires dans le cancer folliculaire de la thyroïde chez l'homme. La TSH induit des fibres de stress dans le FTC-133. Afin d'évaluer les différences dans les plaques d'adhésion, l'expression de la fibronectine (FN) et de son récepteur ont été analysées. Pour ces études, les clones FTC-133, FTC-236 et FTC-238 ont été mis en culture dans le milieu DME-H21 dépourvu en sérum pendant 24 heures avant l'addition de 30 mU/ml de TSH/24 heures. II n'y avait aucune différence quantitative dans l'expression FN sur Western blot que ce soit sur le milieu ainsi conditionné ou sur les extraits cellulaires. Les Western blots et les études immunohistochimiques ont indiqué que la TSH n'induisait la sécrétion de FN que dans la lignée FTC-133. La cytométrie de flux avec l'anticorps 5 a démontré une réduction respectivement de 52% et de 45% (p<0.01) dans l'expression de FnR par les clones FTC-236 et FTC-238, comparé au FTC-133. Cette donnée a été confirmée par l'immunohistochimie. A partir de ces études, nous concluons que les clones d'invasion de FTC diminuent leur expression en FnR sans changer leur expression de FN. De plus, un traitement par la TSH peut induire la sécrétion de FN par le clone FTC-133 alors qu'il ne semble pas influencer le FnR ou l'expression FN. L'expression diminuée des plaques d'adhésion FnR semble potentialiser les métastases dans certains cancers de la thyroïde.
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BACKGROUND: The aims of this study were to compare two new methods (Dmax and CUSUM) for determination of the ventilatory threshold and to examine the consequences of estimation by application of these methods in combination. METHODS: Experimental design: a comparative design was used. Setting: the study was performed in the Exercise Physiology Laboratory in the Faculty of Medicine, Sel?uk University. Participants: thirty-two untrained males (20.6 +/- 1.2 yrs) performed an incremental exercise test on a cycle ergometer. Interventions: there is no intervention. Measures: ventilatory and gas exchange variables were measured breath-by-breath. The ventilatory thresholds were detected by conventional linear regression, CUSUM, Dmax and combined CUSUM-Dmax methods. RESULTS: The ventilatory thresholds determined by Dmax method gave the highest r-values compared to the criterion method. There was no statistical difference between thresholds determined by all methods or by the same method using different variables. Ventilatory thresholds could not be determined by the conventional linear regression method in three subjects but were determined in all subjects by the other three methods. CONCLUSIONS: Although all methods presented in this study can be used in the determination of ventilatory threshold, the Dmax method was found to be the most valid one. When using the CUSUM method, combining it with the Dmax method increases the validity of the measurement.  相似文献   
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Thermal injury of the genitalia usually occurs as part of larger body surface burns. The most common sequelae of burns of the penoscrotal region are contractures of penile shaft, but we did not encounter any reported cases in English Literature with cryptorchidism as a sequel of burn injury. A 7 year old boy with cryptorchidism as a component of extensive perineal and inguinal burn deformity is reported to indicate the role of burn injury in cryptorchidism. Cryptorchidism as a component of perineal burn injury may be caused by the attachment of the cremaster muscle or fascia to the abdominal wall during the process of wound healing. As healing process of wounds on inguinal region by contraction may cause testis entrapment and cryptorchidism, a careful genital examination bears a great importance in inguinal burn deformities in order not to miss any trapped testis and replace it as early as possible before degenerative changes begin.  相似文献   
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