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1.
INTRODUCTION: The purpose of this study was to test the hypothesis that physical training (PT), especially high-intensity PT, would have a favorable effect on components of the insulin resistance syndrome (IRS) in obese adolescents. METHODS: Obese 13- to 16-yr-olds (N = 80) were randomly assigned to one of the following 8-month interventions; 1) lifestyle education (LSE)-alone every 2 wk, 2) LSE+moderate-intensity PT, and 3) LSE+high-intensity PT. PT was offered 5 d x wk(-1). Plasma triacylglycerol (TAG), total cholesterol (TC), high-density lipoprotein cholesterol (HDLC), very low-density lipoprotein cholesterol (VLDLC), low-density lipoprotein cholesterol (LDLC), low-density lipoprotein (low density lipoprotein (LDL)) particle size, apolipoproteins AI and B, glucose, insulin, and blood pressure were measured with standardized methods. RESULTS: The intent-to-treat analyses for all subjects who completed pre- and post-tests regardless of their adherence to the interventions showed that the LSE+high-intensity PT group had more favorable changes than the LSE-alone group in TAG level (P = 0.012), TC/HDLC (P = 0.013), and diastolic blood pressure (P = 0.031). For efficacy analyses, all PT subjects who attended at least 2 d x wk(-1) (40%) were combined into one group (LSE+PT) and compared with the LSE-alone group. These two-group analyses showed significant interactions (P < 0.001) between baseline values and group membership for deltaTAG, deltaVLDLC, and deltaTC/HDLC, such that subjects who had the least favorable baseline values showed the most beneficial impact of the PT. Of particular interest was a favorable effect of the PT on LDL particle size. CONCLUSION: PT, especially high-intensity PT, had a favorable effect on several IRS markers in obese adolescents.  相似文献   

2.
ObjectiveTo identify studies that report three-dimensional (3D) biomechanical analysis of jump-landing tasks in relation to athletes with current patellar tendinopathy (PT), and/or asymptomatic with history of PT or patellar tendon abnormality (PTA) on diagnostic imaging.MethodsFive electronic databases were searched. Included articles were required to: (1) investigate the 3D biomechanics of a jump-landing task; (2) be cross-sectional or longitudinal in design; and (3) include participants that had symptomatic PT, were asymptomatic with a history of PT, asymptomatic with PTA on diagnostic imaging and/or asymptomatic with an unknown pathology or PT history.ResultsThirty-seven statistically significant jump-landing variables were associated with PT, history of PT and/or PTA. The only consistent variable that could be replicated between studies was knee flexion angle at initial foot-ground contact (IC) and an altered hip flexion/extension strategy during a horizontal land phase of a vertical stop-jump.ConclusionIsolated vertical landings or take-offs alone may not be sensitive enough to identify key jump-landing variables associated with PT, thus clinicians and researchers should incorporate a whole jump-landing task with a horizontal landing component. Sagital plane hip and knee kinematics in a horizontal landing phase appear to provide the most valuable information for evaluating those with PT.  相似文献   

3.
Patellar tendinopathy (PT) is a leading cause of morbidity in jump-landing athletes. Landing mechanics are identified as a factor associated with PT and/or patellar tendon abnormality. This study aimed to identify key jump-landing variables associated with PT. Thirty-six junior elite basketball players (men n = 18, women n = 18) were recruited from a Basketball Australia development camp. Three-dimensional (3D) kinematic and ground reaction force (GRF) data during a stop-jump task were collected as well as ultrasound scans of the patellar tendons and recall history of training load data. Mixed-model factorial analyses of variance were used to determine any significant between-group differences. Of the 23 participants included for statistical analyses, 11 had normal bilateral patellar tendons (controls) and eight reported PT (currently symptomatic); however, the four participants categorized as asymptomatic with patellar tendon abnormality on diagnostic imaging were excluded from statistical analyses due to their small sample size. Athletes with PT displayed a similar knee flexion angle at initial foot-ground contact (IC) and hip extension strategy during a stop-jump horizontal landing. Despite a similar kinematic technique, athletes with PT utilized a strategy of a longer stance duration phase from IC to peak force. This strategy did not lead to those athletes with PT decreasing their peak vertical GRF nor patellar tendon force during landing but enabled these athletes to land with a lower rate of loading (control 59.2 ± 39.3 vs. PT 29.4 ± 33.7 BW.s-1). Athletes with PT still reported significantly reduced training volume (control 4.9 ± 1.8 vs PT 1.8 ± 1.1 sessions/wk; total training time/wk control 2.4 ± 1.0 vs PT 1.4 ± 1.1 h/wk).  相似文献   

4.
PURPOSE: To identify reproducible anatomical landmarks that would allow predicting the course of the pyramidal tract (PT) through centrum semiovale. MATERIALS AND METHODS: A total of 20 normal volunteers (12 males, eight females) with a mean age of 34 years (range, 20-59 years) were scanned using a 1.5-Tesla clinical MR unit to assess the trajectory of the PT. Neuroanatomical characteristics of the PT passing through the centrum semiovale were assessed by two independent observers. Tractography data of 10 consecutive patients with brain tumor were used to test the precision of anatomy-based prediction of the tract location. RESULTS: On sagittal view, 95% of the PT depicted on tractography displayed a completely straight or primarily straight course through the supratentorial brain. In 98% of tracts, the bending point of the PT was identified < or = 3 mm from the level of the anterior commissure-posterior commissure (AC-PC) plane. In 80% of PT, the intersection with the AC-PC plane occurred midway between the AC and the PC as seen on the sagittal view. Evaluation of the PT in 10 patients with brain tumor revealed that the anatomy-based prediction of PT on the contralesional hemisphere was not substantially deviated from the actual tractography depicted PT. PT on the lesional hemispheres, however, had deviations of various degrees. CONCLUSION: The course of the PT through supratentorial brain can be predicted based on easily identifiable landmarks. This anatomy-based prediction can be clinically applied for cases without substantial mass effect from a space occupying lesion.  相似文献   

5.
Accuracy of SRM and power tap power monitoring systems for bicycling   总被引:4,自引:0,他引:4  
PURPOSE:: Although manufacturers of bicycle power monitoring devices SRM and Power Tap (PT) claim accuracy to within 2.5%, there are limited scientific data available in support. The purpose of this investigation was to assess the accuracy of SRM and PT under different conditions. METHODS:: First, 19 SRM were calibrated, raced for 11 months, and retested using a dynamic CALRIG (50-1000 W at 100 rpm). Second, using the same procedure, five PT were repeat tested on alternate days. Third, the most accurate SRM and PT were tested for the influence of cadence (60, 80, 100, 120 rpm), temperature (8 and 21 degrees C) and time (1 h at ~300 W) on accuracy. Finally, the same SRM and PT were downloaded and compared after random cadence and gear surges using the CALRIG and on a training ride. RESULTS:: The mean error scores for SRM and PT factory calibration over a range of 50 - 1000 W were 2.3 +/- 4.9% and -2.5 +/- 0.5%, respectively. A second set of trials provided stable results for 15 calibrated SRM after 11 months (-0.8 +/- 1.7%), and follow-up testing of all PT units confirmed these findings (-2.7 +/- 0.1%). Accuracy for SRM and PT was not largely influenced by time and cadence; however, power output readings were noticeably influenced by temperature (5.2% for SRM and 8.4% for PT). During field trials, SRM average and max power were 4.8% and 7.3% lower, respectively, compared with PT. CONCLUSIONS:: When operated according to manufacturers instructions, both SRM and PT offer the coach, athlete, and sport scientist the ability to accurately monitor power output in the lab and the field. Calibration procedures matching performance tests (duration, power, cadence, and temperature) are, however, advised as the error associated with each unit may vary.  相似文献   

6.
Objectives:Abnormal neuronal activity and functional connectivity have been reported in patients with venous pulsatile tinnitus (PT). As neuronal activity is closely coupled to regional brain perfusion, the purpose of this study was to investigate the cerebral blood flow (CBF) alterations in patients with unilateral venous PT using arterial spin labeling (ASL).Methods:This study included patients with right-sided PT between January 2018 and July 2019. A healthy control (HC) group matched 1:1 for gender and age was also recruited. All subjects underwent ASL scanning using 3.0T MRI. The correlation between altered CBF and Tinnitus Handicap Inventory (THI) score as well as PT duration was analyzed.ResultsTwenty-one patients with right-sided PT and 21 HCs were included. The mean PT duration of the patients was 35.9 ± 32.2 months, and the mean THI score was 64.1 ± 20.3. Compared with the HCs, the PT patients exhibited increased CBF in the left inferior parietal gyrus and decreased CBF in the bilateral lingual gyrus (family-wise error corrected, p < 0.05). The increased CBF in the left inferior parietal gyrus showed a positive correlation with the THI score in PT patients (r = 0.501, p = 0.021).ConclusionsPT patients exhibit regional CBF alterations. The increased CBF in the left inferior parietal gyrus may reflect the severity of PT.Advances in knowledge:This study not only presents evidence for the potential neuropathology of PT from the perspective of CBF alterations but also offers a new method for investigating the neuropathological mechanism of PT.  相似文献   

7.
ObjectiveTo investigate the effects of an intervention with tailored exercises on the incidence of patellar tendinopathy (PT) in elite youth jumping athletes.DesignProspective crossover cohort.SettingOne sport club facility.Participants271 elite youth basketball and volleyball player were followed in the first year of the study (Observation year) and 270 athletes were followed in the second year (intervention year).Main outcome measureIncidence rates of PT per 1,000h of exposure. Cox survival analysis was used to verify the effects of the intervention (exercises implemented according to the findings of a preseason assessment) on PT incidence.ResultsThe exercise prevention program significantly reduced the number of cases of PT, with athletes submitted to the intervention showing 51% less risk of developing PT. The overall PT incidence in the Observation year (5.9 per 1,000h of exposure) was significantly higher than that in the intervention year (2.8 per 1,000h of exposure) (P = .037). Twenty-six athletes developed PT in the observation year, whereas 13 athletes developed PT in the intervention year.ConclusionsA tailored preventive program may be able to reduce the incidence of patellar tendinopathy, especially in male youth volleyball athletes. Randomized controlled trials are encouraged to confirm these findings.  相似文献   

8.
目的 探讨并发糖尿病的肺结核患者的临床特点及防治对策。方法 回顾性调查了我院 1988~ 1998年收治的肺结核患者 10 6 3例 ,其中两病并发者 30例 ,运用u检验揭示并发糖尿病的肺结核患者与单纯肺结核患者的差别及合理的治疗方法。结果 并发糖尿病的肺结核患者的痰菌阳性率、治疗失败率及空洞率均显著高于单纯肺结核患者 (P <0 .0 1) ,其治疗原则为及早有效控制糖尿病 ,同时施以合理的抗结核治疗。结论 并发糖尿病的肺结核患者具有痰菌阳性率高 ,传染性强 ,治疗失败率高的特点 ,是肺结核的重要传染源 ,对其早期发现 ,合理治疗对结核病疫情控制有重要意义。  相似文献   

9.
Objective. To compare polytomography (PT) and computed tomography (CT) for visualizing fractures and arthrodeses, with and without metal hardware, to determine whether CT could adequately replace PT. Design and patients. An ex vivo bovine model containing fractures in three planes, reduced with metal hardware, was created to compare fractures using PT and CT. The radiation dose at the skin surface was calculated for both examinations. For in vivo assessment, images of 14 patients who underwent both PT and CT (15 fractures, five arthrodeses) were coded, sorted, and independently read by four musculoskeletal radiologists. They rated the degree of certainty of their assessment. Time factors for patients and personnel and financial costs were also compared. Results. In the ex vivo model the fractures were well seen on both PT and CT. The radiation dose was higher for PT than for CT. In vivo, the degree of certainty in assessment of fractures and arthrodeses was higher for PT than CT in studies in which metal hardware was present, but there was no significant difference in studies without metal hardware or in the combined (with and without hardware) studies. The patient’s and technologist’s time required to perform a PT examination was greater than that for CT. Conclusion. In the assessment of fractures and arthrodeses containing metal hardware, PT is recommended. For studies without hardware, CT is equivalent and can replace PT. Received: 13 July 1998 Revision requested: 1 October 1998 Revision received: 15 March 1999 Accepted: 19 March 1999  相似文献   

10.
Patellar tendinopathy (PT) is a common overuse injury of the patellar tendon in jumping athletes. In a recent large cross‐sectional study from 2008 several factors were identified that may be associated with the etiology of PT. However, because of the study design no conclusions could be drawn about causal relations. The primary aim of the current study is to investigate whether the factors identified in the previous 2008 study can also be prospectively recognized as predictors of symptomatic PT in 2011. Nine hundred twenty‐six Dutch elite and non‐elite basketball and volleyball players from the previous study were invited again to complete an online survey about knee complaints and risk factors for PT in 2011. The logistic regression included 385 athletes of which 51 (13%) developed PT since 2008. Male gender [odds ratio (OR) 2.0, 95% confidence interval (CI) 1.1–3.5] was found to be a risk factor for developing PT. No sports‐related variables could be identified to increase the risk of developing PT, but some evidence was found for performing heavy physically demanding work, like being a nurse or a physical education teacher (OR 2.3, 95% CI 0.9–6.3). These findings indicate that, when considering preventive measures, it is important to take into account the total tendon load.  相似文献   

11.
This study compared lower limb dynamic joint loading after hamstring (HS) and patellar tendon (PT) anterior cruciate ligament (ACL) reconstruction. A three-dimensional motion analysis and force plate system were used to determine sagittal plane kinematics and kinetics in 20 subjects who had undergone ACL reconstruction (10 HS, 10 PT) whilst they performed both horizontal and vertical hopping tasks. Results for both activities showed significantly smaller knee flexion angles and external flexion moments in the operated than the non-operated limbs in PT subjects but no difference between limbs in HS subjects. There was no difference in the summated moment (hip plus knee plus ankle) between limbs for either graft type. The peak vertical ground reaction force was greater in the operated than the non-operated limb in PT subjects during the horizontal hop. These data show functional knee kinematic and kinetic differences between the two graft types that point to an earlier or better functional recovery in patients undergoing ACL reconstruction with HS graft than PT graft.  相似文献   

12.
静滴胺碘酮对抗凝患者凝血酶原时间影响   总被引:4,自引:0,他引:4  
目的 评价静滴胺碘酮对瓣膜置换术后房颤患者凝血酶原时间 (PT)变化的影响。方法 选择风湿性心脏病机械瓣膜置换术后合并快速房颤患者 33例 ,患者均接受静滴胺碘酮治疗 5d ,于静滴胺碘酮前后检查凝血酶原时间。结果 常规剂量华法林抗凝情况下 ,33例患者中PT全部延长。静滴胺碘酮前PT为 (2 1.2± 3.1)s,静滴胺碘酮后PT为 (35 .2±6 .1)s,前后相差显著 ,(P <0 .0 5 )。结论 风湿性心脏病机械瓣膜置换术后合并快速房颤患者在应用胺碘酮静滴治疗快速房颤时 ,应用常规剂量华法林抗凝可使PT明显延长。  相似文献   

13.
Patellar tendinopathy (PT) is one of the most common overuse injuries of the knee. Recent reports indicate that increased body mass is frequently associated with tendinopathy, not only biomechanically but biochemically. Abnormalities of other structures within the knee extensor mechanism [patellofemoral joint (PFJ) alignment and patellar tendon length] that can directly influence the strain distribution of the patellar tendon are inconsistently implicated in PT. The aim of this study was to compare the infrapatellar fat pad volume, patellar tendon length and PFJ alignment in people with chronic PT and a group of age-, gender-, height-, and activity-matched controls with normal tendons. Axial magnetic resonance (MR) images, from 26 participants with PT and 28 control participants were obtained. Fat pad size, patellar tendon length and PFJ alignment were measured digitally from the MR images, using measurement software, and the results compared between the PT group and control group. People with PT had a significantly larger fat pad than healthy controls when controlled for height (P=0.04). Patellar tendon length was not significantly different between groups (P=0.16), nor were there between-group differences for the measures of PFJ alignment (P=0.07-0.76). Thus, the infrapatellar fat pad may play an important role in PT.  相似文献   

14.
目的观察血凝标本的放置时间和离心时间对凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)测定结果的影响。方法对手术前送检(即采即送)合格的标本50份立即测定PT、APTT和在室温下放置2、4、8 h测定PT、APTT;抽取门诊健康体检者血液标本50份,用3 000 r/min的速度离心5、10、15 min后测定PT、APTT。结果 PT、APTT在4 h内测定的结果与即刻比较,差异均无统计学意义(P>0.05),在8 h测定与即刻比较,差异有统计学意义(P<0.05);3 000 r/min的速度离心5、10 min测得结果与离心20 min比较,差异有统计学意义(P<0.05),离心15 min时测得结果与离心20 min比较,差异无统计学意义(P>0.05)。结论检测PT、APTT时应掌握好标本离体后放置的时间以及标本的离心速度和时限。  相似文献   

15.
Patellar tendinopathy (PT ) is a frequent overuse injury of the extensor knee apparatus, whereas as up to 30% of the athletes might suffer from persisting symptoms during their entire career. In the present case‐control study, 47 patients (30.8 ± 11.4 years) with PT with intratendinous alteration (PT ita) of a minimum of ≥25% of the axial surface on MRI and minimum Blazina score of II (pain during without limiting sports activity) were included; MR images were analyzed for trochlear geometry, patellar height/tilt, and tibial tubercle‐trochlear groove distance (TT ‐TG ). The control group (CG ) comprised 87 age‐ and gender‐matched patients without history of anterior knee pain or lateral patellar instability. It was hypothesized that patients with PT might be related to patellofemoral dysplasia. It was found that the patella was significantly higher in patients with PT compared to the CG (patellotrochlear index [PT ‐I]: 0.33 vs 0.37, P  = .014; Insall‐Salvati index [InSa]: 1.18 vs 1.07, P  = .004). PT ‐I was above the cut‐off value in 10.6% of PT knees (CG 5.7%, P  = .27), and InSa in 42.6% (CG 21.8%, P  = .012). TT ‐TG was significantly higher in patients with PT compared to CG (12.0 mm vs 9.9 mm, P  = .002); however, TT ‐TG was only pathologic (>20 mm) in one patient. The trochlear facet ratio was above the cut‐off value in 55.3% of PT patients and 23% of CG (P  < .001), and was significantly greater in patients with PT (0.39 ± 0.09) than CG (0.48 ± 0.1, P  < .001). Knees with PT have significantly more morphological characteristics of patellofemoral instability, which needs to be considered especially in recurrent or treatment‐refractive cases.  相似文献   

16.

Estimation of an individual’s age has important applications in forensics. In young individuals, it often relies on separate evaluations of permanent teeth (PT) and third molars (TM) development. Here, we analysed the age prediction performance of combined information from PT and TM in an unusual sample of healthy Somalis, born and living in Finland. PT development was staged according to Demirjian et al. (Hum Biol, 1973) and TM development according to Köhler et al. (Ann Anat, 1994), using panoramic radiographs from 803 subjects (397 males, 406 females) aged 3–23 years. A sex-specific Bayesian age-estimation model for the multivariate distribution of the stages conditional on age was fitted on PT, TM and PT and TM combined. The age-estimation performances were validated and quantified. The approach combining PT and TM only overestimated age with an ME of − 0.031 years in males and − 0.011 years in females, indicating the best age prediction performance.

  相似文献   

17.
This study compared hamstring (HS) and patellar tendon (PT) anterior cruciate ligament (ACL) reconstruction in females. Sixty-five patients (43 HS, 22 PT) were evaluated at a mean 3.8-year postoperatively. Evaluation included IKDC 2000, SF-36, Cincinnati sports activity scores, anterior knee pain (AKP), kneeling pain, range of motion and anterior knee laxity. One PT patient sustained a traumatic graft rupture. There were no differences between the two grafts in terms of anterior knee laxity or IKDC scores. The HS group had higher sports activity scores and higher scores on the Physical Functioning and General Health subscales of the SF-36. Despite no difference in AKP, there was greater kneeling pain in the PT patients, who also had greater extension deficits. Both HS and PT are satisfactory ACL grafts in females, but HS grafts were associated with less morbidity, greater return to preinjury level of activity and higher quality of life scores.  相似文献   

18.
PURPOSE: The purpose of this study was to compare isokinetic knee (flexion and extension) strength of nondisabled youth (ND; 15 males, 15 females; males = 12.7 +/- 2 yr; females = 13.4 +/- 2 yr) and youths with mental retardations (MR, 17 males + 13 females; male = 14.7 +/- 2 yr; females = 13.6 +/- 2 yr). METHODS: Subjects were evaluated on a Kin-Con isokinetic dynamometer at a speed of 60 degrees x s(-1). Parameters measured were peak torque (PT), time to PT, angle of PT, total work (W), and PT hamstrings/quadriceps (HQ) ratio. Peak torque was also corrected by weight (BW) and body mass index (BMI). Peak torque, time to peak torque, angle of peak torque, and total work were analyzed using a 2 x 2 x 2 (groups x gender x muscle) repeated measures analysis of variance (MANOVA). Flexion/extension ratios, BMI, and BW were analyzed by separate 2 x 2 (group x gender) analyses of variance. RESULTS: Results of this study suggest that: 1) while gender differences are apparent in the ND population they are not evident in individuals with MR; 2) knee extension strength is higher for ND youth, thus causing lower PT HQ ratios when compared with those in youth with MR; 3) angle of PT and time to PT were similar among groups; and 4) total work performed is lower in individuals with MR. CONCLUSIONS: It was concluded that parameters of strength production in individuals with MR are not consistent and do not follow the same pattern as their nonretarded peers.  相似文献   

19.
The effect of treadmill physical training (PT) on rat gastrocnemius/plantaris muscle after bilateral femoral artery ligation was investigated. To enable a comparison to be made between the susceptibility of muscles with restricted blood flow and normally perfused skeletal muscle to PT, animals without ligated femoral arteries also underwent PT. PT increased the oxidative capacity of the gastrocnemius/plantaris muscle, as judged by the activity of citrate synthase, and reduced muscle fatigue in both groups of animals. Exercise also tended to lower the activity of a marker enzyme for glycolysis, glyceraldehyde-phosphate dehydrogenase in all animals, although this only reached the level of statistical significance in the animals with ligated femoral arteries. In the animals with restricted muscle blood flow, PT increased gastrocnemius skeletal muscle blood flow and pO2 and prolonged the time taken to attain maximum muscle twitch tension. The results indicate a great susceptibility of hindlimb skeletal muscles of rats with ligated femoral arteries to PT. They also suggest that the beneficial effect of PT observed in man with chronic occlusive arterial disease (COAD) may result both from an increase in muscle blood flow and from an enhanced mitochondrial respiratory activity in the afflicted muscle.  相似文献   

20.
The physiological bone-ligament junction is composed of four zones: ligament, fibrocartilage, calcified fibrocartilage and bone. It plays a very important part in the distribution of mechanical loads applied to ligaments so as to diminish stress concentration or shearing at the interface. This paper examines types of bone and neoligament insertion after anterior cruciate ligament (ACL) reconstruction with a Dacron prothesis, the Leeds-Keio scaffold ligament (LK), patellar tendon with LAD augmentation (PT+LAD) and bone patellar tendon bone alone (PT). The anterior cruciate reconstructions were implanted in 16 sheep via double-isometric bone tunnels without postoperative knee immobilization. Histological examination of the new insertions (using haematoxylin-cosin, Giemsa, Masson, and Mallory stains) was performed following animal sacrifice after 2, 3, 6 and 9 months. A layer of fibrocartilage between the bone and the ligament was observed with PT, followed by a nearly normal insertion after 6 months. With PT, followed by PT+LAD, the augmentation was surrounded by fibrous tissue (also noted inside the LAD). The PT insertion was virtually physiological after 3–6 months. With the LK scaffold, fibrous tissue was noted in and around the scaffold, even after 6 and 9 months. With the Dacron prosthesis, fibrous tissue around the ligament was unaccompanied by ingrowth into the prosthesis. Nerve endings (pacinian corpuscles) were only present in the PT. These findings show that even after 9 months artificial ligaments are separated from bone by fibrous tissue and devoid of the histological and biomechanical features of a physiological junction. PT alone was the only technique that resulted in formation of a structure very similar to the physiological junction, capable of protecting the bone against excessive shearing stress and the tendon against excessive strains.  相似文献   

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