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排序方式: 共有978条查询结果,搜索用时 46 毫秒
1.
Moshe Yaniv Tali Becker Michal Goldwirt Sam Khamis David M Steinberg Shlomo Weintroub 《Clinical journal of sport medicine》2006,16(5):392-396
OBJECTIVE: Little is known about the interactions of sports-related demands and human body, in particular on musculoskeletal features, during growth. Focusing on the relationship between soccer and lower limb alignment, we examined the hypothesis that varus knee deviation is more prevalent among high-performance pediatric and adolescent soccer players. DESIGN: Cross-sectional study with focused sampling. SETTING: First league sports clubs. PARTICIPANTS: 106 male child/adolescent soccer players aged 10 to 21 years and 68 age-matched tennis players. INTERVENTIONS: All athletes completed a demographic questionnaire and underwent physical examinations, which included height, weight, generalized laxity, knee, ankle, foot and spine axis, hip range of motion, tibial torsion, Q angle, foot navicular height, and progression angle. MAIN OUTCOME MEASUREMENT: Varus/valgus axis was determined by the intercondylar intermalleolar distance while standing. Soccer and tennis players were compared on knee axis and other outcome variables by analysis of covariance, adjusting for age and by t-tests within age groups. RESULTS: A significantly higher prevalence of knee varus was found among the soccer players compared to that among the tennis players. The difference in intracondylar distance was statistically significant after the age of 13 years (P < 0.001). In addition, compared to tennis players, soccer players had higher foot arches, decreased hip external rotation and increased external tibial torsion. CONCLUSIONS: Varus knee axis deviation was more common among children and adolescent soccer players than among tennis players. The prevalence was more pronounced among players aged 13 years or older. Further research is needed to explore the rationale of this phenomenon. 相似文献
2.
W T Yuh E T Tali H D Nguyen T M Simonson N A Mayr D J Fisher 《AJNR. American journal of neuroradiology》1995,16(2):373
PURPOSETo evaluate the effect of MR contrast dose versus delayed imaging time on the detection of metastatic brain lesions based on lesion size.METHODSContrast MR examinations with gadoteridol were obtained in 45 patients with brain metastases. The patients were divided into two groups: 16 received cumulative standard dose (0.1 mmol/kg) and 29 received cumulative triple dose (0.3 mmol/kg). Both groups were evaluated at two dose levels (lower dose and higher dose) with two separate injections. Each patient received an initial bolus injection of either 0.05 (cumulative standard dose) or 0.1 (cumulative triple dose) mmol/kg of gadoteridol to reach the lower-dose level and underwent imaging immediately and 10 and 20 minutes later. Thirty minutes after injection, an additional bolus injection of 0.05 (cumulative standard dose) or 0.2 (cumulative triple dose) mmol/kg was administered to reach the cumulative higher-dose level (cumulative standard dose, 0.1 mmol/kg; cumulative triple dose, 0.3 mmol). Images were acquired immediately.RESULTSThere was no difference in the detection rate for lesions larger than 10 mm among T2-weighted, lower-dose immediate and delayed, or immediate higher-dose images in both study groups. Lesions smaller than 10 mm had improved detection with delayed imaging in both study groups; however, the immediate higher-dose studies still had the highest detection rate.CONCLUSIONIn the evaluation of small central nervous system metastases, either delayed imaging after the injection of standard contrast dose or higher contrast dose may improve their detection, and therefore affect clinical management. Higher contrast dose (cumulative triple dose) studies appear to be more effective than delayed imaging with standard dose. 相似文献
3.
J Goldhahn M Reinhold M Stauber C Knop R Frei E Schneider B Linke 《Journal of orthopaedic research》2006,24(5):917-925
The goal of our study was to evaluate two newly developed implant designs and their behavior in terms of subsidence in lumbar vertebral bodies under cyclic loading. The new implants were evaluated in two different configurations (two small prototypes vs. one large prototype with similar load-bearing area) in comparison to a conventional screw-based implant (MACS TL). A pool of 13 spines with a total of 65 vertebrae was used to establish five testing groups of similar bone mineral density (BMD) distribution with eight lumbar vertebrae each. In additional to BMD assessment via dual-energy X-ray absorptiometry, cancellous BMD and structural parameters were determined using a new generation in vivo 3D-pQCT. The specimens were loaded sinusoidally in force control at 1 Hz for 1000 cycles at three load levels (100, 200, and 400 N). A survival analysis using the number of cycles until failure (Cox regression with covariates) was applied to reveal differences between implant groups. All new prototype configurations except the large cylinder survived significantly longer than the control group. The number of cycles until failure was significantly correlated with the structural parameter Tb.Sp. and similarly with the cancellous BMD for three of five implants. In both large prototypes the cycle number until failure significantly correlated with the preoperative distance to the upper endplates. Although the direct relationship between bone structure or density and mechanical breakage behavior cannot be conclusively proven, all the prototypes adapted for poor bone structure performed better than the comparable conventional implant. 相似文献
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Addiction in women has many implications in the field of obstetrics and gynecology. Particularly in obstetrical care, the health needs of the unborn as well as of the pregnant patients have to be considered. Therefore, early somatic and psychosocial help should be offered to pregnant women with addiction disorders. The main elements of this concept will be presented along with a summary of typical comorbidity issues in these patients, the handling of drug-related emergencies, and the management of perioperative replacement therapy. 相似文献
7.
The forces produced during stretches of passive and activated muscles, and isometric force deficits after stretching of activated
muscles were examined in rat plantor flexor muscle-tendon complexes with reduced collagen cross-links (pyridinoline). Female
Sprague-Dawley rats (n=6, age 87 days) were injected twice daily for 43 days with β-aminopropionitrile (BAPN, 333 mg/kg/day i.p.), an inhibitor
of lysyl oxidase, which is responsible for the production of collagen cross-links. The relative weights of the plantar flexor
muscles were similar for BAPN and saline-injected (control, C) rats (n=6). Pyridinoline was lower in the tendon (22.9%), and in the plantaris (17.1%), and soleus (7.4%) muscles (P<0.05), with no changes observed in collagen content (hydroxyproline), as determined by high-pressure liquid chromatography.
At an ankle position of 90°, groups had similar forces at 5, 10, 20, 40, 60 and 80 Hz before stretching. Forces at 40° with
stretches of the passive muscles (five times from 90° to 40°) were lower for all stretches in BAPN-injected rats (P<0.05). Isometric force deficits resulting from stretches of activated muscles (80 Hz, 20 times from 90° to 40°, rest intervals
3 min) followed similar courses for BAPN-injected and C rats, and were 51.1 (2.4)% (C) and 54.7 (4.6)% (BAPN) before the last
stretch. After 1 h of rest, isometric force deficits were 26% and 29% larger at 10 Hz and 5 Hz, respectively, in BAPN-treated
rats (P<0.05). The reduction in BAPN-injected collagen cross-linking of the skeletal muscle-tendon complex reduced the forces produced
during stretches without muscle stimulation (i.e. passive stretch), and stretching of activated muscles produced larger isometric
force deficits only at low stimulation frequencies.
Electronic Publication 相似文献
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9.
Semiautomated quantification of hepatitis B virus DNA in a routine diagnostic laboratory 总被引:1,自引:0,他引:1
Kessler HH Stelzl E Daghofer E Santner BI Marth E Lackner H Stauber RE 《Clinical and diagnostic laboratory immunology》2000,7(5):853-855
The Cobas Amplicor HBV Monitor test for quantitative determination of hepatitis B virus (HBV) DNA in serum has recently been introduced. To evaluate the performance of this assay in a routine diagnostic laboratory, reproducibility of results was determined with the First European Union Concerted Action HBV Proficiency Panel and the Accurun 325 HBV DNA Positive Control, Series 300. Results for 270 routine serum samples were additionally evaluated. To avoid the retesting of a large number of samples due to titers exceeding the upper limit for the linear range of the assay, sera of patients with chronic hepatitis B (CHB) were diluted prior to the assay to 10(-4) in normal human plasma, which is included in the assay. The mean coefficient of variation was 22.9% for all input HBV DNAs. Of 270 routine serum samples, 182 (150 sera from transplant donors and 32 sera from patients who had recovered from CHB) tested negative. Eighty-six sera were found to be HBV DNA positive; in six sera, HBV DNA levels were found to exceed the upper limit for the linear range of the assay and had to be retested. In the remaining two sera, inhibition occurred. The semiautomated Cobas Amplicor HBV Monitor test showed sufficient reproducibility and helped in avoiding human error. The relatively narrow linear range of detection is a limitation of the new assay. 相似文献
10.
R. G. Cutlip Dr. W. T. Stauber R. H. Willison T. A. McIntosh K. H. Means 《Medical & biological engineering & computing》1997,35(5):540-543
A dynamometer is designed and fabricated to measure the force output during static and dynamic muscle actions of the plantar
flexor muscles of anaesthetised rats in vivo. The design is based on a computer-controlled DC servomotor capable of angular
velocities in excess of 17.5 rad s−1. The system controls the range of motion, angular velocity and electrical stimulation of the muscles, while monitoring the
force output at the plantar surface of the foot. The force output is measured by a piezo-electric load cell that is rated
at 5 kg capacity. Angular velocity and position are measured by a DC tachometer and potentiometer, respectively. All measurement
devices are linear (r2=0.9998). The design minimises inertial loading during high-speed angular motions, with a variation in force output of less
than 0.2%. The dynamometer proves to be an accurate and reliable system for quantifying static and dynamic forces of rat plantar
flexor muscles in vivo. 相似文献