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91.
Exercise adaptations to strength, anaerobic and aerobic training have been extensively studied in adults, however, young people appear to respond differently to such exercise stimulus in comparison to adults. In addition, because overtraining in young athletes has received little attention, this important area is also discussed. Resistance training in children can be safe and effective. It has the potential to improve sport performance, enhance body composition and reduce the rate of sport incurred injury. Furthermore, with the appropriate stimulus, prepubertal and adolescent athletes can show significant increments in muscle strength (13 - 30%). Children can improve anaerobic power (3%-10% Mean Power and 4%-20% in Peak Power), although the mechanisms responsible for the improvements in children remain unclear. Children show a ‘reduced’ trainability of peak VO2 in comparison to adults. Nevertheless, their aerobic power is trainable, with improvements reported at approximately 5%. Moreover, improvements in other variables like exercise economy or lactate threshold may occur without significant changes in peak VO2 The limited evidence available indicates that overtraining is occurring in young athletes (30% prevalence), highlighting the importance of further research in to all the possible contributing factors - physiological, psychological and emotional - when investigating overtraining.

Key points

  • Children’s strength, anaerobic and aerobic power is trainable, although the improvements may be smaller than seen in adults.
  • Children can demonstrate significant gains in muscle strength with resistance training (13 - 30%).
  • Improvements in mean power (3 - 10%) and peak power (4 - 20%) are reported in children.
  • Aerobic fitness can improve with training in children by approximately 5%.
  • Limited available evidence indicates an occurrence of overtraining in young athletes of around 30%.
Key Words: Prepubertal and adolescent athletes, trainability, mechanisms, resistance training, anaerobic training, aerobic training, overtraining  相似文献   
92.
Although breast reconstruction with deep inferior epigastric perforator (DIEP) flap is a well-described technique, few publications have specifically reported the technical aspects and the outcome following skin-sparing mastectomy (SSM). The aim of this study is to analyse the feasibility of its immediate application and to describe the operative planning, outcome and complications after SSM. 27 patients underwent 30 DIEP flap breast reconstructions with all immediate and 3 bilateral. Mean time of follow-up was 29 months. Breast skin, DIEP Flap and donor-site complications were evaluated. Information on patient satisfaction was collected. 70% had tumors measuring 2 cm or less (T1) and 74% were stage 0 and I according to American Joint Committee on Cancer. Breast skin complications occurred in 7.4%, all represented by small areas of skin necrosis. Partial losses were observed in two (7.4%) patients (less than 15% of total area) and total DIEP loss in 1 (3.7%). Donor-site complications represented by bulging occurred in only one patient (3.7%). The majority of patients were either very satisfied or satisfied. One local recurrence was observed. All complications except 2 were treated by a conservative approach. The DIEP flap is a reliable technique for SSM reconstruction. Success depends on patient selection, coordinated planning with the oncologic surgeon and careful intraoperative and postoperative management. The main advantage is that patients can safely undergo dual procedures with the added aesthetic benefits in breast and abdominal donor site.  相似文献   
93.
PURPOSE: Since long-term patency and device integrity of nitinol stents in SFA lesions are not well studied, we examined clinical outcome, patency and device integrity after stenting long lesions using a standardized implantation technique. METHODS: Between 2001 and 2006, 59 patients (74 lesions) were treated with the same nitinol self-expandable stent (Zilver, Cook, USA) and technique for SFA recanalization. Clinical charts and imaging were retrospectively reviewed for patency (primary and assisted-primary), and device integrity. RESULTS: Patients were 74.5 (10.9) years old (range 49 to 93), 64% male, 42% diabetic, 62% hypertensive and 67% current or former smokers. Lesions were 23% TASC B, 16% TASC C, or 61% TASC D. Mean recanalization length was 19 cm (range 3 to 53). Mean number of stents per patient was 2.8 (total 210). Mean follow-up time was 2.4 years (range 3 days to 4.8 years). Kaplan-Meier estimates for primary patency rates were 90%, 78%, 74%, 69%, and 69% at 1, 2, 3, 4 and 4.8 years, respectively. Ten restenoses at a mean of 500 (388) days (1-1251 days) were successfully recanalized. The assisted primary patency rates were 96%, 90%, 90%, 90% and 90% at 1, 2, 3, 4 and 5 years, respectively. Six complete occlusions could not be reverted by a second recanalization procedure, and were treated by surgical bypass (1 case), amputation (3 cases), or medical management (2 cases). One (1.04%) Class II stent fracture was noted. CONCLUSIONS: SFA recanalization with a standardized implantation technique and nitinol stents provides good long-term primary and assisted-primary patency.  相似文献   
94.
The objective of this study was to explore whether the items from a specific outcome measure, that is, Disabilities of the Arm, Shoulder, and Hand (DASH), for quantifying limb symptoms and functions in musculoskeletal disorders fit into the framework of the International Classification of Functioning, Disability and Health (ICF). All DASH items were compared to the ICF according to eight linking rules. Two groups of researchers performed the linking independently, and the results were compared by correlation. The 30 DASH items and four items from the optional modules were linked to 63 ICF categories and 11 chapters: 15 categories belong to the ICF body functions component and 48 to the activities and participation component. There were no items coded under the components body structure or environmental factors. Kappa index showed an agreement of 0.73 (p<0.001). The results showed that the content of the DASH does link well with the ICF framework. Clinicians and researchers must attend to the fact that certain domains and categories from the ICF are not covered by the DASH. Limitations of the instrument may be overcome by simultaneously using other instruments that address the intended content.  相似文献   
95.
Background The aim of this study was to search for mutations in the humanmutS homolog 2 (hMSH2) and humanmutL homolog 1 (hMLH1) genes in 25 unrelated Brazilian kindreds with suspected hereditary nonpolyposis colorectal cancer (HNPCC). Methods The families were grouped according to the following clinical criteria: Amsterdam I or II; familial colorectal cancer (CRC); an early age of onset of CRC in the proband only; or with at least one or two relatives who had HNPCC-related cancers; CRC in the proband only. All patients were studied with direct sequencing. Results Ten mutations were detected (10 of 25 [40%]); of nine different mutations, seven were novel. ThehMLH1 gene had a higher mutation detection rate thanhMSH2 (8 of 25 [32%] vs. 2 of 25 [8%]). Only 3 of these 10 families fulfilled the Amsterdam criteria. Two different polymorphisms were detected in thehMLH1 gene and four in thehMSH2 gene. Conclusions ThehMLH1 gene had a higher mutation detection rate thanhMSH2. The physician who deals with CRC must take into consideration the heredity issue with patients who present with an early age of onset or a familial history of CRC- or HNPCC-related cancers, including gastric cancer, even if they do not fulfill the former Amsterdam criteria.  相似文献   
96.
97.

Introduction

Left atrioventricular valve regurgitation is the most concerning residual lesion after surgical correction of atrioventricular septal defect.

Objective

To determine factors associated with moderate or greater left atrioventricular valve regurgitation within 30 days of surgical repair of incomplete atrioventricular septal defect.

Methods

We assessed the results of 51 consecutive patients 14 years-old and younger presenting with incomplete atrioventricular septal defect that were operated on at our practice between 2002 and 2010. The following variables were considered: age, weight, absence of Down syndrome, grade of preoperative left atrioventricular valve regurgitation, abnormalities on the left atrioventricular valve and the use of annuloplasty. The median age was 4.1 years; the median weight was 13.4 Kg; 37.2% had Down syndrome. At the time of preoperative evaluation, there were 23 cases with moderate or greater left atrioventricular valve regurgitation (45.1%). Abnormalities on the left atrioventricular valve were found in 17.6%; annuloplasty was performed in 21.6%.

Results

At the time of postoperative evaluation, there were 12 cases with moderate or greater left atrioventricular valve regurgitation (23.5%). The variation between pre- and postoperative grades of left atrioventricular valve regurgitation of patients with atrioventricular valve malformation did not reach significance (P=0.26), unlike patients without such abnormalities (P=0.016). During univariate analysis, only absence of Down syndrome was statistically significant (P=0.02). However, after a multivariate analysis, none of the factors reached significance.

Conclusion

None of the factors studied was determinant of a moderate or greater left atrioventricular valve regurgitation within the first 30 days of repair of incomplete atrioventricular septal defect in the sample. Patients without abnormalities on the left atrioventricular valve benefit more of the operation.  相似文献   
98.
IntroductionLiver transplantation is the standard treatment for end-stage liver disease. Brazil holds the third highest number of liver transplants performed per year, but center maldistribution results in high discrepancies in accessing this treatment. In 2012, an interstate partnership successfully implemented a new liver transplantation program in the middle west of Brazil. Here, we report the results of the first 500 liver transplants performed in this new program and discuss the impacts of a new transplant center in regional transplantation dynamics.MethodsWe reviewed data from the first 500 consecutive deceased donor liver transplants performed in the new program during an 8-year period. We analyzed data on patients’ clinical and demographic profiles, postoperative outcomes, and graft and recipient survival rates. Univariate survival analysis was conducted using log-rank tests to compare the groups.ResultsAlmost half (48%) of the procured organs and 40% of the recipients transplanted in our center were from outside our state. Recipient 30-day mortality was 9%. Overall recipient survival at 1 year and 5 years was 85% and 80%, respectively. Mortality was significantly associated with higher Model for End-Stage Liver Disease (P < .001) but not with the presence of hepatocellular carcinoma (P = .795).DiscussionThe new transplantation program treated patients from different regions of Brazil and became the reference center in liver transplantation for the middle west region. Despite the recent implementation, our outcomes are comparable to experienced centers around the world. This model can inspire the creation of new transplantation programs aiming to democratize access to liver transplantation nationwide.  相似文献   
99.
The purpose of this review was to carry out an analysis of the liver regenerative process focusing on the molecular interactions involved in this process. The authors undertook a review of scientific publications with a focus on the liver regeneration. The cellular processes involved in liver regeneration require multiple systematic actions related to cytokines and growth factors. These interactions result in the initiation of mitogenic potential of the hepatocytes. The action of these modulators in the regenerative process require a processing in the extra-cellular matrix. Serines and metal proteins are responsible for the bio availability of cytokines and growth factors so that they can interact as receptors in the cellular membrane generating signaling events for the beginning and end of the liver regenerative process. The exact mechanism of interaction between cells, cytokines and growth factors is not well established yet. A series of ordered events that result in the hepatic tissue regeneration has been described. The better understanding of these interactions should provide a new approach of the treatment for liver diseases, aiming at inducing the regenerative process.  相似文献   
100.
IntroductionNeuromuscular disease (NMD) patients frequently have impaired cough. Mechanical insufflation-exsufflation (MI-E) has proven efficacy in improving airway clearance, however data related to its long-term home use is lacking. The purpose of this study was to describe indications, safety and compliance of home MI-E in NMD patients.MethodsFour years observational analysis of 21 NMD patients on home MI-E. Diagnosis included bulbar and non-bulbar Amyotrophic Lateral Sclerosis (ALS) and other NMD. Median age was 58 years. Only cooperative patients with unassisted baseline Peak Cough Flow (PCF) < 270 L/min were included. All patients were under continuous mechanical ventilation (6 by tracheostomy). Pulmonary function before initiation of MI-E (median): FVC = 0.81 L, MIP = 28 cmH2O, MEP = 22 cmH2O and PCF = 60 L/min. MI-E was performed by previously trained non-professional caregivers, with an on-call support of a trained health care professional. Patients had pulse oximetry monitorization and applied MI-E whenever SpO2 < 95 %. Median follow-up was 12 months (3-41 months).ResultsTen patients (9 ALS) used MI-E daily. Eleven patients used MI-E intermittently, during exacerbations, and in 8 patients early application of MI-E (guided by oximetry feed-back) avoided hospitalization. All tracheostomized patients used MI-E daily and more times a day than patients under NIV. Four patients (3 bulbar ALS), were hospitalized due to secretion encumbrance. MI-E was well-tolerated and there were no complications. In general, caregivers considered MI-E effective. During this period, 4 patients died, related to disease progression.ConclusionsHome MI-E is well tolerated, effective and safe if used by well trained caregivers. MI-E should be considered as a complement to mechanical ventilation.  相似文献   
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