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81.
Aims: The aims of this study were to evaluate patterns of handgrip (HG) strength in relation to gender and age in English schoolchildren and to compare this with existing data and produce reference data for this population. Methods: The HG of 7147 English schoolchildren (3773 boys and 3374 girls) aged 10–15.9 years was measured using a portable Takei handgrip dynamometer (Takei Scientific Instruments Co. Ltd, Tokyo, Japan). Centile data were produced using the Generalized Additive Models for Location, Scale and Shape. Z‐scores were generated using existing data for European children. Age and gender interactions were analysed using analysis of covariance. Results: In boys and girls, significant increases in HG were found between every age‐group (p < 0.001). Boys were significantly stronger than girls at every age (p < 0.001) and the boys’ age‐related increase was significantly greater than the girls’ (p < 0.001). Conclusion: This study provides reference data for handgrip strength in English schoolchildren. Handgrip strength in English children is broadly similar to existing European data, after adjusting for mass and stature. These data could be used for clinical or athletic screening of low and high strength in this population.  相似文献   
82.
Fetal surgery in the primate. III. Maternal outcome after fetal surgery   总被引:1,自引:0,他引:1  
Maternal safety and future reproduction potential are paramount considerations in fetal surgery. In a series of 102 fetal surgical procedures on time-dated pregnant monkeys, we examined the maternal complications, the potential for future pregnancy, and the effects of uterine staples used for hysterotomy and uterine closure. There were significant maternal complications associated with the development of the present techniques for fetal surgery including 3 maternal deaths, 5 uterine ruptures, and 5 cases of wound infection of dehiscence. All were preventable with knowledge gained from this experience. Compared with a control unoperated breeding colony, fetal surgery did not interfere with subsequent reproductive capacity in animals that had uterine closure with absorbable sutures. However, metal staple hysterotomy resulted in a markedly decreased fertility rate probably related to exposure of the endometrial cavity to a permanent foreign body. Although serious maternal complications occurred in this series, many are avoidable as we improve both our obstetric management and our anesthetic and surgical techniques. Prenatal intervention carries considerable maternal risk and should not be attempted clinically under any but the most rigorous conditions.  相似文献   
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Superparamagnetic iron oxide (AMI-25), a reticuloendothelial cell-specific contrast agent for magnetic resonance (MR) imaging, was evaluated for its ability to permit detection of splenic metastases in 18 patients. Superparamagnetic iron oxide, at a dose of 30 mumol of iron per kilogram, decreased the signal intensity of spleen from 19.5 +/- 4.8 to 3.1 +/- 2.2 (spin-echo sequence, repetition time msec/echo time msec = 1,500/42; P less than .05), without changing the signal intensity of tumor. As a result, the tumor-spleen contrast-to-noise ratio increased from 0.2 (tumor isointense relative to spleen) to 18.0 (tumor hyperintense relative to spleen). As a consequence of increased contrast, splenic tumors were detected in four of 18 patients (45 individual lesions; P less than .05), whereas nonenhanced MR imaging permitted detection of splenic lesions in only two of 18 patients (four individual lesions). Maximum tumor-spleen contrast was achieved within 60 minutes after intravenous administration. These initial clinical results indicate that MR imaging with superparamagnetic iron oxide may offer improved accuracy in the diagnosis of splenic tumors.  相似文献   
85.
Fetal sacrococcygeal teratoma   总被引:6,自引:1,他引:5  
Sacrococcygeal teratoma (SCT) is being diagnosed before birth with increasing frequency. We were recently consulted about management of a 22-week fetus with SCT and reviewed our experience (6 cases) and the literature. We found that most fetal SCT present from 22 to 34 weeks gestation with a uterus enlarged by the tumor and/or associated polyhydramnios; although the American Academy of Pediatrics Surgical Section clinical classification is an important prognostic indicator in neonatal SCT, it does not appear to predict outcome in fetal SCT; associated chromosomal abnormalities or life threatening anomalies are rare; presentation after 30-weeks gestation is a relatively good prognostic sign with fetal survival, after planned cesarean delivery, in 6 of 8 cases; and hydrops and/or placentomegaly in association with fetal SCT predicts fetal demise soon after diagnosis with 7 of 7 cases dying in utero.  相似文献   
86.
Diverse materials with varying physical and magnetic properties have been evaluated as gastrointestinal contrast agents for magnetic resonance (MR) imaging. Uniform marking of the small bowel remains the greatest challenge. Ferrites are magnetically active iron oxide particles that are miscible with water and cause loss of signal on MR images. The decrease in MR signal intensity produced by ferrites occurs with a wide range of iron concentrations (0.1-10 mM) and with both T1- and T2-weighted pulse sequences. These effects of ferrites are explained by predominant T2 shortening with negligible T1 effects. The ferrite preparation used in this study was stable in vitro, with little iron solubilized by acid. Intragastric administration of ferrite (5 mg of iron per kg in 6 ml) routinely marked the small bowel of rats. The authors conclude that ferrites represent a promising new class of contrast agents for gastrointestinal MR imaging.  相似文献   
87.
BACKGROUND: Different protocols have been used for narrowband ultraviolet B (UVB) therapy, commonly used in the treatment of psoriasis; however, more effective and reliable protocols are still required. OBJECTIVE: The aim of this study was to compare the weekly and daily dose increment protocols of narrowband UVB phototherapy in psoriasis patients. METHODS: Thirty patients with plaque psoriasis underwent narrowband UVB treatment three times a week and 15 patients selected consecutively among these patients underwent a weekly (once in three treatments) dose increment whereas the remaining 15 patients underwent a daily dose increment. Patients were monitored for 10 weeks and evaluated by the Psoriasis Area Severity Index (PASI). RESULTS: When the two groups were evaluated according to median PASI scores prior to the treatment and during 10 weeks of treatment, there was no statistically significant difference between the groups (P > 0.05). During the treatment lasting for 10 weeks, four patients in the group with a weekly dose increment and three patients in the group with a daily dose increment recovered and no statistically significant difference was detected between the groups (P > 0.05). The groups were also evaluated according to the median cumulative dose. The median cumulative dose was higher in the group with a daily dose increment and the difference between the groups was statistically significant (P = 0.002). CONCLUSION: The application of daily dose increments was no better than that of weekly dose increments in narrowband UVB treatment for psoriasis. Therefore, although our results may need to be supported by large-series studies, we conclude that application of weekly dose increments with a lower cumulative dose having the same efficacy is preferred in narrowband UVB treatment of psoriasis.  相似文献   
88.
Systemic mastocytosis: CT and US features of abdominal manifestations   总被引:2,自引:0,他引:2  
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