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861.
BACKGROUND: Despite the high prevalence of childhood obesity among U.S. Hispanic children and adolescents, quantitative, objective data on their patterns and levels of physical activity are scarce. OBJECTIVES: 1) To describe qualitatively the types of physical activities in which nonoverweight and overweight Hispanic children and adolescents participate; 2) to use accelerometry to quantitatively describe the duration, intensity, and frequency of physical activity; 3) to examine the influence of age, gender, and BMI status on physical activity levels; and 4) to determine the relationships between physical activity and adiposity, fitness, and risk for the metabolic syndrome. METHODS: Cross-sectional assessment of physical activity using accelerometers was made for three continuous days in 897 nonoverweight and overweight Hispanic children, ages 4-19 yr. Ancillary measurements included blood pressure, anthropometry, body composition by dual-energy x-ray absorptiometry, fitness by VO2peak test, and metabolic risk factors, using standard clinical and biochemical methods. RESULTS: Types and levels of physical activity were influenced by age, gender, and body mass index (BMI) status. Total physical activity counts declined markedly with increasing age (P = 0.001) and were consistently higher in boys than in girls (P = 0.001). Total activity counts were lower (P = 0.002) and sedentary activity counts were higher in overweight than in nonoverweight children (P = 0.001). Sleep duration (min.d(-1)) was slightly lower in overweight compared with nonoverweight children, ages 4-8 yr (P = 0.03). Physical activity levels were significantly associated with percent FM, VO2peak, fasting serum insulin, and waist circumference, although the strength of the associations were generally low. CONCLUSION: Efforts should be made to shift the time in sedentary activity to light activity, and to increase the time spent in moderate to vigorous activity in U.S. Hispanic children and adolescents, with special attention given to the overweight, girls, and adolescents.  相似文献   
862.
We surveyed 57 caregivers of children with Cornelia de Lange syndrome (CdLS) using a self-report questionnaire designed to elicit their experiences with receiving information regarding health complications associated with this multisystem disorder. Their most frequent sources of information at the time of diagnosis were a health care provider (86%) and the CdLS Foundation (72%). Although most caregivers (82%) indicated a desire to receive information about all possible CdLS related health complications, on average they recalled receiving information on only 64% of their child's current or future health complications. For two of the top three complications (as ranked by caregivers), information was available to fewer than half of the caregivers at diagnosis. Only 40% of caregivers were satisfied with the amount of information received at diagnosis, while only 45% felt that the information they received was useful. Caregivers indicated a preference for receiving information in written format (59%) or verbally (39%). Our results indicate that caregivers of children with CdLS report a high need for information at diagnosis, regarding their child's actual or potential health complications. Dissatisfaction may result both from a deficiency in information provided, as well as a mismatch between issues mentioned and those that caregivers deem most important. Caregivers may benefit maximally from receiving information in person at the time of diagnosis as well as having an additional written source of information. These findings highlight the importance of complementary sources of information for caregivers and are likely to be relevant for other multisystem disorders.  相似文献   
863.
A qualitative study using a grounded theory approach investigated adolescents' perceptions about complementary/alternative medicine (CAM) use. Adolescents, attending a clinic at the Canadian College of Naturopathic Medicine, were interviewed after receiving ethics approval. Data were collected using semi-structured interviews. The decision of adolescents to use CAM was based within the context of their world and how it shaped influencing factors. Factors that influenced adolescents' decision to use CAM were identified as certain personality traits, culture, media, social contacts and the ability of CAM providers to develop therapeutic relationships. The barriers and benefits of CAM use influenced evaluation of choices. The importance of barriers in limiting freedom of choice in health care decisions should be investigated by practitioners as they provide care to adolescents. Health care planning for integrative models of care requires determining the "right" blend of expertise by knowing interprofessional boundaries, determining mixed skill sets to provide the essential services and ensuring appropriate regulation that allows practitioners to use their full scope of practice.  相似文献   
864.
Electrospinning has garnered special attention recently due to its flexibility in producing extracellular matrix-like non-woven fibers on the nano-/microscale and its ability to easily fabricate seamless three-dimensional tubular conduits. Biosyn(?), a bioabsorbable co-polymer of glycolide, dioxanone, and trimethylene carbonate, was successfully electrospun into tubular conduits for the first time for soft tissue applications. At an electric field strength of 1 kV cm(-1) over a distance of 22 cm (between the Taylor cone and the collector) and at a flow rate of 1.5 ml h(-1) different concentrations of Biosyn/HFP solutions (5-20%) were spun into nanofibers and collected on a rotating mandrel (diameter 4 mm) at 300 and 3125 r.p.m. Scaffolds were characterized for structural and morphological properties by differential scanning calorimetry and scanning electron microscopy and for mechanical properties by uniaxial tensile testing (in both the circumferential and longitudinal directions). Biosyn(?) tubular scaffolds (internal diameter 4 mm) have been shown to exhibit a highly porous structure (60-70%) with a randomly oriented nanofibrous morphology. The polymer solution concentration directly affects spinnability and fiber diameter. At very low concentrations (≤5%) droplets were formed due to electrospraying. However, as the concentration increased the solution viscosity increased and a "bead-on-string" morphology was observed at 10%. A further increase in concentration to 13% resulted in "bead-free" nanofibers with diameters in the range 500-700 nm. Higher concentrations (≥20%) resulted in the formation of microfibers (1-1.4 μm diameter) due to increased solution viscosity. It has also been noted that increasing the mandrel speed from 300 to 3125 r.p.m. produced a reduction in the fiber size. Uniaxial tensile testing of the scaffolds revealed the mechanical properties to be attractive for soft tissue applications. As the fiber diameters of the scaffold decrease the tensile strength and modulus increase. There is no drastic change in tensile properties of the scaffolds tested under hydrated and dry conditions. However, a detailed study on the biodegradation and biomechanics of electrospun Biosyn conduits under physiological pressure conditions is required to ensure potential application as a vascular graft.  相似文献   
865.
The effect of sulfated cyclodextrins on Plasmodium falciparum cultures was determined. alpha-, beta-, and gamma-Cyclodextrins having equal degrees of sulfation inhibited parasite viability to a similar degree, a result suggesting that the ring size of the cyclodextrin is not a critical factor for inhibitory activity. beta-Cyclodextrins containing fewer than two sulfate groups had no inhibitory activity, however, compounds containing 7-17 sulfates were found to be active in the microM range. Examination of treated cultures indicated that intracellular forms of the parasite were unaffected; however, increased numbers of extracellular merozoites were present. Active compounds produced enhanced erythrocyte staining with cationic dyes that could be reduced by stilbene disulfonates, a result suggesting that sulfated cyclodextrins inhibit parasite growth by interacting with the anion transport protein, AE1. Compounds that were found to be active in P. falciparum cultures were also found to inhibit P. berghei merozoite entry and could reduce the parasitemia of P. berghei infection in a mouse model, results suggesting that these compounds inhibit a common step in the merozoite invasion process of at least two Plasmodium species.  相似文献   
866.
A postal survey was used to collect data from family members of deceased residents of six long-term care (LTC) facilities in order to explore end-of-life (EOL) care using the Family Perception of Care Scale. This article reports on the results of thematic analysis of family member comments provided while completing the survey. Family comments fell into two themes: (1) appreciation for care and (2) concerns with care. The appreciation for care theme included the following subthemes: psychosocial support, family care, and spiritual care. The concerns with care theme included the subthemes: physical care, staffing levels, staff knowledge, physician availability, communication, and physical environment. This study identified the need for improvement in EOL care skills among LTC staff and attending physicians. As such, there is a need to implement continuing education to address these issues.  相似文献   
867.
A quadricuspid aortic valve (QAV) is a rare congenital heart defect, previously described as an incidental finding at the time of surgery or postmortem, which is now being increasingly detected by 2D transthoracic or transesophageal echocardiogram. With advances in echocardiography, secondary cardiac anomalies are also being described in association with QAV. Herein we describe a patient with QAV with a secundum atrial septal defect.  相似文献   
868.
Preterm babies with retinopathy of prematurity (ROP) can become blind if they do not receive appropriate timely intervention. The presence of cataract in these individuals in addition to visual deprivation amblyopia, also delays proper screening, adequate treatment, and makes follow-up assessment difficult. Anatomical differences in these infants and amblyopia management, especially in unilateral cataract, are other important concerns, and hence, management of these cases with cataract and ROP is challenging. In this review, studies where ROP cases were associated with cataract, were evaluated with a focus on preterm individuals less than 6 months age. Preterm babies are at increased risk of developing cataract because of systemic factors. In addition, those with ROP may have cataract associated with retinal detachment or treatment received. The type of cataract, risk factors, and pathophysiology associated with each cause varies. This review highlights these different aspects of cataract in ROP including causes, pathophysiology, types of cataracts, and management. The management of these cases is critical in terms of the timing of cataract surgery and the challenges associated with surgery and posterior segment management for ROP. Anatomical differences, preoperative retina status, pupillary dilatation, neovascularization of iris in aggressive posterior ROP, fundus examination, amblyopia, and follow-up are various important aspects in the management of the same. The preoperative workup, intraoperative challenges, postoperative care, and rehabilitation in these individuals are discussed.  相似文献   
869.
870.
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