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61.
Rodriguez CJ Sacco RL Sciacca RR Boden-Albala B Homma S Di Tullio MR 《Journal of the American College of Cardiology》2002,39(9):1482-1488
OBJECTIVES: The goal of this study was to determine whether the risk of ischemic stroke associated with increased left ventricular mass (LVM) is modified by physical activity (PA). BACKGROUND: Increased LVM is associated with an increased risk for stroke. Physical activity can decrease the risk of stroke and may have variable effects on LVM. METHODS: We used a case-control study design in a multiethnic population in northern Manhattan, New York, to study 394 case subjects who had a first ischemic stroke and 413 stroke-free control subjects. All subjects were interviewed and two-dimensional echocardiograms obtained to determine LVM. RESULTS: A sharp increase in risk of ischemic stroke was seen in the highest quartile of LVM (odds ratio [OR]: 6.14 [95% confidence interval [CI]: 3.04 to 12.38]). Thus, increased LVM was defined by the highest quartile of LVM. In multivariate analysis, the effect of increased LVM on the risk of stroke was significantly decreased by the presence of any level of PA versus no PA (OR: 1.59 [95% CI: 0.99 to 2.57] p < 0.07 vs. 3.53 [95% CI: 1.94 to 6.42] p < 0.0001). Although PA decreased the risk of stroke in all patients, the effect was stronger in subjects with increased LVM than among those without increased LVM (p = 0.033). CONCLUSIONS: Increased LVM is associated with an increased risk of stroke, especially among sedentary patients. Physical activity decreases the risk of stroke among patients with increased LVM to a level comparable to that of patients without increased LVM. Recommending PA may be a nonpharmacologic tool to reduce the stroke risk, especially among patients with increased LVM. 相似文献
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64.
Optimized isolation and expansion of human airway epithelial basal cells from endobronchial biopsy samples
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Kate H.C. Gowers Robert E. Hynds Ricky M. Thakrar Bernadette Carroll Martin A. Birchall Sam M. Janes 《Journal of tissue engineering and regenerative medicine》2018,12(1):e313-e317
Autologous airway epithelial cells have been used in clinical tissue‐engineered airway transplantation procedures with a view to assisting mucosal regeneration and restoring mucociliary escalator function. However, limited time is available for epithelial cell expansion due to the urgent nature of these interventions and slow epithelial regeneration has been observed in patients. Human airway epithelial cells can be expanded from small biopsies or brushings taken during bronchoscopy procedures, but the optimal mode of tissue acquisition from patients has not been investigated. Here, we compared endobronchial brushing and endobronchial biopsy samples in terms of their cell number and their ability to initiate basal epithelial stem cell cultures. We found that direct co‐culture of samples with 3T3‐J2 feeder cells in culture medium containing a Rho‐associated protein kinase inhibitor, Y‐27632, led to the selective expansion of greater numbers of basal epithelial stem cells during the critical early stages of culture than traditional techniques. Additionally, we established the benefit of initiating cell cultures from cell suspensions, either using brushing samples or through enzymatic digestion of biopsies, over explant culture. Primary epithelial cell cultures were initiated from endobronchial biopsy samples that had been cryopreserved before the initiation of cell cultures, suggesting that cryopreservation could eliminate the requirement for close proximity between the clinical facility in which biopsy samples are taken and the specialist laboratory in which epithelial cells are cultured. Overall, our results suggest ways to expedite epithelial cell preparation in future airway cell therapy or bioengineered airway transplantation procedures. 相似文献
65.
A comparison of different methods of red blood cell leukoreduction and additive solutions on the accumulation of neutrophil‐priming activity during storage
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66.
Balán Iván C. Lentz Cody Giguere Rebecca Dolezal Curtis Kajura-Manyindo Clare Kutner Bryan A. Zalwango Aisha Makoni Rujeko Madlala Bernadette Makala Yvonne Khanyile Nombuso Kadyamusuma McLoddy Kachenjera Lonely Ndhlovu-Forde Zanele Tuswa-Haynes NoCamagu 《AIDS and behavior》2022,26(3):698-708
AIDS and Behavior - Evidence-based adherence counseling interventions must be delivered with fidelity to ensure that their effectiveness is retained, but little is known regarding how counselors in... 相似文献
67.
Elopre Latesha Boutwell Alexander Gordon Bretia Johnson Bernadette Marrazzo Jeanne Van Der Pol Barbara Mugavero Michael J. 《AIDS and behavior》2022,26(11):3469-3479
AIDS and Behavior - To assess PrEP service delivery preferences among Black cis-gender women living in urban and rural settings in Alabama, we conducted a cross-sectional discrete choice experiment... 相似文献
68.
Sorvillo F Mazziotti G Carbone A Piscopo M Rotondi M Cioffi M Musto P Biondi B Iorio S Amato G Carella C 《The Journal of clinical endocrinology and metabolism》2003,88(10):4818-4822
In this study, we have investigated in vivo the time-dependent effects of TSH on vascular endothelial growth factor (VEGF) production in patients monitored for thyroid carcinoma. Serum VEGF, thyroglobulin (Tg), and TSH levels were assayed at baseline and 6, 24, 30, 48, 72, and 96 h and 1 wk after administration of recombinant human TSH (rhTSH) in 45 thyroidectomized patients affected by differentiated thyroid carcinoma. At baseline, the patients with metastasis (18 cases) showed serum Tg and VEGF values significantly higher than those seen in the cured patients (27 cases). During rhTSH stimulation, the mean VEGF levels decreased significantly in both patient groups. In 60% of patients with metastasis, VEGF nadir occurred at the same time as serum TSH reached the highest values, whereas in 85.7% of the cured patients VEGF decreased after the TSH peak (P = 0.003). In conclusion, we demonstrate for the first time that short-term administration of rhTSH in patients monitored for differentiated thyroid carcinoma induces a significant reduction in serum VEGF values even in the absence of thyroid tissue. This result would suggest that TSH may be able in vivo to regulate VEGF production from tissues other than the thyroid gland. 相似文献
69.
The serum of a patient who developed a posttransfusion purpura contained antibodies directed against a previously undescribed platelet antigen Lek a. The antiplatelet activity was present in the IgG fraction and was detected by immunofluorescence, 51Cr lysis and 14C-serotonin release. The frequency of the Lek a phenotype in the French population is 98.18%. Lek a does not appear to be sex-linked and seems to be closely related to the Bak a antigen. The Lek a antigen is not expressed on thrombasthenic platelets but is found on platelets from patients with the Bernard-Soulier syndrome which suggests that this antigen is carried by platelet glycoproteins IIb and/or IIIa. 相似文献
70.
Dr Bernadette L. Matthews Kim L. Bennell Heather A. Mckay Karim M. Khan Adam D. G. Baxter-Jones Robert L. Mirwald 《Annals of human biology》2013,40(3):342-356
Background: The effects of systematic sports training during childhood and adolescence on subsequent growth and sexual maturation remains in dispute.Aim: The study aimed to determine whether moderate–high volumes of dance training adversely influence linear growth and sexual maturation of young girls progressing through puberty.Subjects and methods: This 3-year mixed longitudinal study comprised 82 novice dancers and 61 controls, aged 8–11 years at baseline, who were assessed bi-annually for 3 consecutive years. A biological maturational age was determined by estimating attainment of age at peak height velocity (PHV). Body dimensions were measured by anthropometry, and exercise levels, nutritional intake and age at menarche by questionnaires.Results: Controls had significantly greater unadjusted height velocity than dancers 1 year before PHV, however there was no difference between groups in age of attainment of PHV. When controlling for maturation, lean mass, fat mass and extracurricular sport (excluding dancing), there were no group differences in absolute growth or velocity of growth in height, sitting height or leg length. Within the dancers there were no effects of years of dancing (>6.5 years) or weekly dance hours (>7?h per week) on growth velocities. No association was found between age at menarche and years or hours of dance training.Conclusion: Results suggest that moderate–high levels of dance training do not affect linear growth and maturation. Thus, girls should not be discouraged from dance participation on the basis of potential growth delays.Résumé. Arrière plan: On reste partagé sur les effets que l’entraînement sportif systématique pendant l’enfance et l’adolescence, peut avoir sur la croissance et sur la maturation sexuelle.Objectif: L’étude cherche à savoir si l’entraînement moyen ou intensif à la danse, influence négativement la croissance linéaire et la maturation sexuelle des filles en cours de puberté.Sujets et méthodes: Cette étude semi longitunale de trois ans impliquait 82 danseuses novices et 61 contrôles, âgées de 8 à 11 ans au départ, qui ont été examinées deux fois par an pendant trois années consécutives. Un âge de maturation biologique a été déterminé en estimant à quel âge survenait la croissance staturale de pic (CSP). Les dimensions corporelles ont été mesurées par anthropométrie et les niveaux d’activité physique, ainsi que l’alimentation et l’âge aux premières règles, ont été renseignés par questionnaires.Résultats: Les contrôles présentent une croissance staturale non ajustée significativement plus élevée que celle des danseuses, un an avant la CSP, mais il n’y a cependant pas de différence d’âge d’atteinte de la CSP entre les groupes. A maturation, masse maigre, masse grasse et sport non programmé constants (à l’exclusion de la danse), il n’y a pas de différences entre les groupes, ni en croissance absolue, ni en vélocité de croissance staturale, taille assis ou longueur de la jambe. Parmi les danseuses, on n’observe aucun effet du nombre d’années de danse (>6,5 ans) ou du nombre d’heures de danse hebdomadaire (>7h par semaine) sur les vitesses de croissance. On n’a pas trouvé d’association entre le nombre d’heures d’entraînement à la danse et l’âge aux premières règles.Conclusion: Les résultats suggèrent que des niveaux d’entraînement à la danse de modérés à élevés n’affectent pas la croissance linéaire ni la maturation. Les filles ne doivent donc pas être dissuadées de pratiquer la danse sur la crainte d’un retard de croissance potentiel.Zusammenfassung. Hintergrund: Die Wirkung systematischen sportlichen Trainings während Kindheit und Adoleszenz auf das folgende Wachstum und die sexuelle Reifung wird noch kontrovers diskutiert.Ziel: Das Ziel der Untersuchung war die Bestimmung, ob mäßig bis sehr intensives Tanztraining einen nachteiligen Einfluss auf das lineare Wachstum und die sexuelle Reifung junger Mädchen während ihrer pubertären Entwicklung hat.Probanden und Methoden: Diese dreijährige, gemischt longitudinale Studie umfasste 82 neu anfangende Tänzerinnen und 61 Kontrollen, die zu Beginn der Studie 8 bis 11 Jahre alt waren und hernach in 6-montigen Abständen für 3 weitere Jahre untersucht wurden. Ein biologisches Reifealter wurde durch Schätzung des Alters zum Zeitpunkt der maximalen Wachstumsgeschwindigkeit (peak height velocity, PHV) bestimmt. Körpermaße wurden mittels Anthropometrie bestimmt, sowie sportliche Leistung, Ernährung und Menarchealter mittels Fragebogen.Ergebnisse: Unkorrigiert hatten Kontrollen eine signifikant größere Wachstumsgeschwindigkeit als Tänzerinnen ein Jahr vor PHV, allerdings gab es keinen Unterschied zwischen den Gruppen hinsichtlich des Alters bei Erreichen der PHV. Wenn für Reifestatus, fettfreie Körpermasse, Fettmasse und zusätzliche sportliche Aktivität (neben dem Tanzen) korrigiert wurde, gab es keine Gruppenunterschiede mehr hinsichtlich der absoluten Zunahme oder der Wachstumsgeschwindigkeit von Körperhöhe, Sitzhöhe oder Beinlänge. Unter den Tänzerinnen gab es keine Unterschiede hinsichtlich der Anzahl der Tanzjahre (>6,5?Jahre) oder der wöchentlichen Tanzstunden (>7?h?pro Woche) auf die Wachstumsgeschwindigkeit. Es wurden keine Beziehungen zwischen Menarchealter und der Anzahl der Tanzjahre oder der wöchentlichen Tanztrainingsstunden gefunden.Zusammenfassung: Die Ergebnisse sprechen dafür, dass ein mäßig bis sehr intensives Tanztraining keinen Einfluss auf lineares Wachstum und körperliche Reifung hat. Aus diesem Grunde sollten Mädchen nicht von der Teilnahme am Tanzen abgeschreckt werden, nur weil eine mögliche Beeinträchtigung des Wachstums befürchtet wird.Resumen. Antecedentes: Los efectos del entrenamiento deportivo sistemático durante la infancia y adolescencia sobre el crecimiento y la maduración sexual siguen siendo objeto de debate.Objetivo: El estudio intenta determinar si los niveles moderados y/o altos de entrenamiento en danza influyen adversamente sobre el crecimiento lineal y la maduración sexual de las chicas jóvenes que están progresando hacia la pubertad.Sujetos y métodos: Este estudio semi-longitudinal de 3 años de duración incluía a 82 bailarinas principiantes y 61 controles, de entre 8 y 11 años de edad como punto de comparación, que fueron estudiadas bianualmente durante tres años consecutivos. La edad biológica de maduración se determinó estimando la edad a la que se alcanzaba el pico de velocidad en el crecimiento estatural (PHV). Las dimensiones corporales fueron medidas por antropometría, y los niveles de ejercicio, la ingesta nutricional y la edad de menarquia mediante cuestionarios.Resultados: Las chicas control tenían velocidades estaturales no ajustadas significativamente mayores que las bailarinas 1 año antes del PHV, aunque no había diferencias significativas entre los grupos en cuanto a la edad a la que se alcanzaba el PHV. Cuando se controlaba para la maduración, la masa magra, la masa grasa y el deporte extra-curricular (excluyendo la danza), no había diferencias entre los grupos en el crecimiento absoluto o en la velocidad de crecimiento en estatura, talla sentado o longitud de la pierna. Entre las bailarinas, no había efectos debidos a los años que llevaban bailando (> 6,5 años) o las horas de baile semanales (> 7 horas/semana ) sobre las velocidades de crecimiento. No se encontró ninguna asociación entre la edad de menarquia y los años u horas de entrenamiento en danza.Conclusión: Los resultados sugieren que los niveles moderados y/o altos de entrenamiento en danza no afectan ni al crecimiento lineal ni a la maduración. Por tanto, las chicas no deberían renunciar a practicar danza basándose en supuestos retrasos de su potencial de crecimiento. 相似文献