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1.
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   
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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   
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Seventeen patients who underwent vitreal surgery received ceftriaxone (Rocephin) 1-2 g intramuscularly at various time intervals before surgery. Specimens of serum and vitreous were assayed for ceftriaxone concentrations both by bioassay and high pressure liquid chromatography. All patients had detectable vitreous (and serum) ceftriaxone concentrations at all time periods. Vitreous ceftriaxone levels at the first 4.5 hr following the administration of the antibiotic ranged from 1.4-19.4 micrograms/ml and averaged 5.9 micrograms/ml. At 12-13 hr following ceftriaxone administration vitreous concentrations were 11.5 (+/- 9.0) micrograms/ml. Ceftriaxone in intramuscular administration could be used as prophylaxis against ceftriaxone-susceptible microorganisms in vitreal surgery. Ceftriaxone is the first antibiotic for which reliable penetration into the vitreous is demonstrable following intramuscular administration.  相似文献   
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Hoffman  Amnon  Alfon  Jose  Siegal  Tzony  Siegal  Tali 《Pharmaceutical research》1994,11(4):536-540
The purpose of this investigation was to determine whether paraplegia induced by neoplastic cord compression affects the pharmacodynamics of phenobarbital general anesthesia or of pentylenetet-razol (PTZ)-induced convulsions. Paraplegic rats harboring a thora-columbar epidural tumor, or an identical hindlimb tumor mass, received an i.v. infusion of phenobarbital until the onset of anesthesia. At that point, the phenobarbital concentrations in the CSF and serum were measured. Similarly, PTZ was infused until the onset of maximal seizures. It was found that changes related to systemic tumor growth and newly developed paraplegia due to neoplastic spinal cord compression did not attenuate the pharmacodynamics of phenobarbital. However, sustained paraplegia of 4 days duration reduced CNS sensitivity to the hypnotic action of the barbiturate as evidenced by the higher cerebrospinal fluid phenobarbital concentration required to induce anesthesia (170 ± 31 vs 125 ± 20 mg/L; P < 0.05). On the other hand, sustained paraplegia did not affect brain threshold concentration for PTZ-induced seizures.  相似文献   
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OBJECTIVE: The study was designed to investigate obstetric risk factors and pregnancy outcome of patients with pruritic urticarial papules and plaques of pregnancy (PUPPP). METHODS: A population-based study comparing all pregnancies of women with and without PUPPP was conducted. Deliveries occurred during the years 1988-2002 at the Soroka University Medical Center. A multivariable logistic regression model was constructed in order to find independent risk factors associated with PUPPP. RESULTS: During a 15-year period, 159 197 deliveries took place. PUPPP complicated 42 (0.03%) of all pregnancies. Using a multivariable analysis, the following conditions were significantly associated with PUPPP: multiple pregnancies (odds ratio (OR) = 4.9, 95% confidence interval (CI) 1.7-14.1), hypertensive disorders (OR = 2.2, 95% CI 1.1-4.7), and induction of labor (OR = 7.6, 95% CI 4.0-14.5). Higher rates of 5-minute Apgar scores lower than 7 (OR = 8.0, 95% CI 4.4-14.9) and of cesarean deliveries (OR = 2.9, 95% CI 1.5-5.6) were noted in the PUPPP as compared to the comparison group. While investigating other perinatal outcome parameters such as oligohydramnios, intrauterine growth restriction, meconium-stained amniotic fluid and perinatal mortality, no significant differences were observed between the groups. CONCLUSION: Pruritic urticarial papules and plaques of pregnancy is a condition significantly associated with multiple pregnancies, hypertensive disorders, and induction of labor. Perinatal outcome is comparable to pregnancies without PUPPP.  相似文献   
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Fetal and postnatal bone development in humans is traditionally viewed as a process characterized by progressively increasing mineral density. Yet, a temporary decrease in mineral density has been described in the long bones of infants in the immediate postnatal period. The mechanism that underlies this phenomenon, as well as its causes and consequences, remain unclear. Using daily μCT scans of murine femora and tibiae during perinatal development, we show that a temporary decrease in tissue mineral density (TMD) is evident in mice. By monitoring spatial and temporal structural changes during normal growth and in a mouse strain in which osteoclasts are non-functional (Src-null), we show that endosteal bone resorption is the main cause for the perinatal decrease in TMD. Mechanical testing revealed that this temporary decrease is correlated with reduced stiffness of the bones. We also show, by administration of a progestational agent to pregnant mice, that the decrease in TMD is not the result of parturition itself. This study provides a comprehensive view of perinatal long bone development in mice, and describes the process as well as the consequences of density fluctuation during this period.  相似文献   
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