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HSS Journal ® - Laminectomy is commonly used in the treatment of lumbar spine pathology. Laminectomies are increasingly being performed in outpatient settings, but patient safety concerns...  相似文献   
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As the prevalence of HIV infection continues to increase, EPs will be called upon to evaluate increasing numbers of AIDS patients who have abdominal pain, some of whom will require emergent surgical intervention. In addition to the myriad causes of abdominal pain in the nonimmunocompromised patient, the differential diagnosis in the AIDS patient includes a wide variety of opportunistic infections and neoplasms (Table 5). Evaluation frequently requires extensive laboratory studies and cultures and advanced imaging (CT, ultrasound, and so forth). A low threshold for surgical and other subspecialty consultation should be in place because of the often subtle presentation of surgical emergencies in AIDS patients.  相似文献   
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Strains of Citrobacter freundii intermediate to cefotaxime but sensitive to ceftazidime were isolated from four different patients in Canada. Sequencing of PCR products by use of CTX-M-specific primers revealed a new combination of four amino acid substitutions. This new gene was designated bla(CTX-M-30) and was encoded on a 3-kb plasmid. The pI of CTX-M-30 was 8.0.  相似文献   
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The current study addressed the role of visual information in the control of locomotion in people with Parkinson's disease. Twelve healthy individuals and 12 mild to moderate Parkinson's disease patients were examined while walking at self-selected velocities, under three visual sampling conditions: dynamic (normal lighting), static (static visual samples) and voluntary visual sampling. Subjects wore liquid crystal glasses for visual manipulation. Outcome measures included spatial-temporal parameters, braking and propulsive impulses, number of samples and total duration of voluntary visual samples. Interaction between groups and visual conditions was not observed for kinematic parameters or braking and propulsive impulses. There were no significant differences between groups for voluntary visual sampling variables. These findings suggest that the visual control of locomotion in Parkinson's disease patients was similar to that observed in controls. Furthermore, Parkinson's disease patients were not more dependent on visual information than healthy individuals for the locomotion control.  相似文献   
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We previously reported on the emergence of macrolide-resistant pharyngeal isolates of group A streptococci (GAS) in our community. The purpose of the present study was to track longitudinal trends in macrolide resistance in these isolates in southwestern Pennsylvania. Testing for susceptibility to erythromycin and clindamycin was performed for all pharyngeal GAS isolates recovered at the Children's Hospital of Pittsburgh and a local pediatric practice between September 2001 and May 2002. Macrolide resistance phenotypes and genotypes were determined by double-disk diffusion and PCR, respectively. Strain relatedness was determined by field inversion gel electrophoresis and emm gene sequence typing. A total of 708 isolates of GAS were recovered during the study period; 68 (9.6%) were macrolide resistant, while all isolates were sensitive to clindamycin. The monthly prevalence of macrolide resistance ranged from 0 to 41%. Only 21 of 573 (3.7%) strains recovered from September 2001 through March 2002 were macrolide resistant. A sudden increase in the rate of macrolide resistance (47 of 135 isolates [35%]) was seen in April and May 2002. Sixty-two isolates demonstrated the M phenotype (resistance to macrolide antibiotics), and six isolates demonstrated the MLS(B) phenotype (resistance to most macrolide, lincosamide, and streptogramin B antibiotics); these isolates were confirmed to be mef(A) and erm(A), respectively. Three unique mef(A) clones and four unique erm(A) clones were identified among the resistant isolates. The MIC at which 50% of isolates are inhibited (MIC(50)) for the mef(A) strains was 16 micro g/ml, while the MIC(50) for erm(A) strains was 8 micro g/ml. The finding of high levels of macrolide resistance among pharyngeal isolates of GAS for a second successive year in our community raises the concern that this problem may be more common in the United States than was previously appreciated. Longitudinal surveillance of isolates from multiple centers is needed to define the prevalence of antimicrobial agent-resistant GAS in the United States.  相似文献   
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