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1.
ABSTRACT

Objective

To investigate primary care physician clinical practice patterns, barriers, and education surrounding pediatric physical activity (PA), and to compare practice patterns by discipline.  相似文献   
2.
Rabies virus was isolated by cell culture from the brains of 104 confirmed rabies cases diagnosed by the fluorescent-antibody staining technique in the United States during 1974-1984. Eighty-seven isolates were obtained from wild-life species, 10 from humans, and seven from domestic animals. These isolates were tested in virus neutralization and immunofluorescence assays using a panel of 34 monoclonal antibodies specific for rabies virus nucleocapsid protein, 44 monoclonal antibodies specific for rabies virus glycoprotein, and two monoclonal antibodies specific for rabies virus nucleocapsid-associated phosphoprotein. Using discriminant analysis, a distinctly different reactivity pattern was revealed between virus isolates from terrestrial (raccoon, skunk) and nonterrestrial (bat) reservoir hosts. The usefulness of this approach for studying the epidemiology of rabies and for predicting the source of infection when this information is unknown is discussed.  相似文献   
3.
OBJECTIVES: To determine whether a stepwise diagnostic paradigm is more diagnostically efficient and cost-effective than a simultaneous testing approach in the evaluation of idiopathic pediatric sensorineural hearing loss (SNHL). DESIGN: Prospective prevalence study. SETTING: Tertiary referral children's hospital. PATIENTS: Consecutive children (n = 150) presenting with idiopathic SNHL in the last 2 years. INTERVENTIONS: All children were evaluated with full diagnostic evaluations including GJB2 screens, temporal bone computed tomography scans, and laboratory investigations. MAIN OUTCOME MEASURES: 1) Diagnostic yields of GJB2 screens, imaging, and laboratory results per SNHL category; 2) Cost analysis comparing a sequential versus a simultaneous testing approach. RESULTS: Overall, 12.0% of patients had biallelic mutations in the GJB2 gene, whereas 30% of patients had an abnormality on temporal bone scan. Laboratory testing did not reveal the SNHL etiology in any patient. While maintaining diagnostic accuracy, significant cost savings were inferred by using a sequential diagnostic algorithm. Our data show children with severe to profound SNHL should first be tested with a GJB2 screen, as opposed to those with milder SNHL, who should undergo imaging as the initial testing step. In patients with initially positive GJB2 or imaging screens, logistic regression analysis significantly predicted negative results on further testing. CONCLUSIONS: A stepwise diagnostic paradigm tailored to the level of the hearing loss in children with bilateral SNHL is more diagnostically efficient and cost effective than the more commonly used full, simultaneous testing approach. Laboratory investigation should not be routine but based on clinical history.  相似文献   
4.
OBJECTIVE: Female athletes who are at increased risk for anterior cruciate ligament (ACL) injury demonstrate biomechanical differences between limbs during athletic tasks that may persist following anterior cruciate ligament reconstruction (ACLR). This may limit an athlete's potential for safe return to sports competition. The purpose of this study was to determine if female athletes demonstrate lower limb asymmetries in landing and takeoff force following ACLR and clearance for return to competitive sports participation. We hypothesized that females following ACLR would demonstrate side-to-side differences in landing and jumping kinetics after their return to sport (2+ years) that would not be observed in a group of healthy female controls. DESIGN: Case control study. SETTING: The Sports Medicine Biodynamics Center at Cincinnati Children's Hospital Medical Center. PATIENTS: Fourteen female athletes at a mean of 27 months following ACLR and 18 healthy female athletes participated in the study. ASSESSMENT: All subjects executed a drop vertical jump (DVJ) task onto 2 force plates. Vertical ground reaction force (VGRF) was measured during landing and takeoff and was used to calculate landing phase loading rates. A 2-way analysis of variance was used to determine differences between the involved, uninvolved, and control limbs. RESULTS: Females who had undergone ACLR demonstrated increased VGRF (P = 0.001) and loading rate (P < 0.001) on the uninvolved limb during landing when compared with the involved limb and the control group. During takeoff, the involved limb showed significantly less ability to generate force (P = 0.03) than the uninvolved limb and the control limbs. CONCLUSIONS: Female athletes who have undergone ACLR and returned to sport may continue to demonstrate biomechanical limb asymmetries 2 years or more after reconstruction that can be identified during landing.  相似文献   
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Cis-diammine dichloroplatinum (cisplatin) is an effective anticancerdrug which forms adducts with DNA, in both bacterial and mammaliancells. It is suspected of producing tumors as well. To determinethe molecular nature of geneti alterations induced by cisplatin,we cloned and sequenced cisplatin-induced mutants in the adeninephosphoribosyl-transferase (aprt) gene of Cinese hamster ovary(CHO) cells. Mutation by cisplatin appears to be targeted asthe sites of mutation are consistent with the known bindingspecificity of cisplatin. Many mutations occur at or proximalto the sequence 5'-AGG-3' and 5'-GAG-3' and include transversions,transitions, frameshifts and short deletions and duplications.Several double changes were also observed. No major rearrangementswere recovered in our collection. At several locations, a numberof mutants were found to be clustered within a small targetregion, but unlike traditional hotspots, tese represent diversechanges occurring in a localized region of a few base pairs.  相似文献   
9.
Congenital epulis of the newborn is a rare gingival tumor that occurs along the alveolar ridge. We report the prenatal sonographic and postnatal MR imaging findings in an infant with maxillary and mandibular congenital epulides.  相似文献   
10.
Conclusion This article summarizes the training and teaching of radiology residents before they attempt unsupervised emergency call, as reported in the radiologic literature. It is hoped that this report will prompt a serious evaluation of the responsibilities of radiology residents assigned to the emergency center and a reconsideration of the radiologic training and experience provided to radiology residents before they are required to assume these responsibilities. Clearly, education and training in radiology appropriate to the responsibilities expected of the on-call emergency radiology resident are required to assure optimum patient care.  相似文献   
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