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991.
BACKGROUND: Several models that integrate trauma and emergency general surgery (EGS) have been proposed to provide a diverse and challenging operative practice for trauma surgeons and improve recruitment. In July 2002, our institution established a 24/7 EGS consult service, staffed primarily by critical care/trauma surgeons (CCTS). The objective of this report was to evaluate the impact of this new service on CCTS, general surgeons (GS) and the hospital. METHODS: All admissions to CCTS and GS from July 1, 2000 to June 30, 2003 were reviewed by querying hospital and physician databases for demographics, diagnoses, operative intervention(s), and resource utilization. Data were analyzed using nonparametric methods. RESULTS: [See ]. 9,405 admissions were identified, with GS and EGS admissions increasing over time. In July 2002, EGS became a separate service and captured 26% of GS admissions. Hospital-wide trauma admissions remained stable despite a slight decrease in trauma admissions to CCTS. A decrease in trauma operations by CCTS was offset by an increased EGS operative volume. EGS included "bread and butter" GS procedures including appendectomies and cholecystectomies and complex surgical procedures. EGS patients were often sicker with more than 50% requiring ICU admission compared with GS admissions of which only 10% required ICU care.(Table is included in full-text article.) CONCLUSIONS: Departmental restructuring to include an EGS service: 1) increased CCTS volume despite decreased CCTS trauma admissions and operations; 2) increased elective GS volume; 3) generated increased use of ICU and operating room resources; and 4) demonstrated that CCTS with broad operative GS backgrounds and critical care knowledge can effectively staff an EGS service.  相似文献   
992.
993.
OBJECTIVE: To explore the potential benefits of using motion sickness bands (MSBs) to control nausea and vomiting in a hospice-based patient population. METHODS: A nonblinded, yearlong observational study. RESULTS: From February 2003 to February 2004, 33 patients entered into the study. The mean age of the study cohort was 67 years, with a predominance of females to males and cancer as the most common admitting diagnosis. Twenty-nine of the 33 patients studied showed a positive response to the intervention for a response rate of 88 percent. CONCLUSIONS: MSBs demonstrated efficacy in controlling nausea and vomiting in a group of hospice patients. Added benefits of patient empowerment and financial savings also were noted. Further study is warranted.  相似文献   
994.
Invasive group A Streptococcus (GAS) infections can be fatal and can occur in healthy children. A case-control study identified factors associated with pediatric disease. Case-patients were identified when Streptococcus pyogenes was isolated from a normally sterile site, and matched controls (>or=2) were identified by using sequential-digit dialing. All participants were noninstitutionalized surveillance-area residents <18 years of age. Conditional regression identified factors associated with invasive disease: other children living in the home (odds ratio [OR]=16.85, p=0.0002) and new use of nonsteroidal antiinflammatory drugs (OR=10.64, p=0.005) were associated with increased risk. More rooms in the home (OR=0.67, p=0.03) and household member(s) with runny nose (OR=0.09, p=0.002) were associated with decreased risk. Among children, household-level characteristics that influence exposure to GAS most affect development of invasive disease.  相似文献   
995.
996.
Adaptation to mechanical loading has been studied extensively in cortical, but not cancellous bone. However, corticocancellous sites are more relevant to osteoporosis and related fracture risk of the hip and spine. We tested the hypotheses that adaptation in a long bone would be greater at cancellous than cortical sites and would depend on the term of daily in vivo cyclic axial loading. We applied compressive loads to the adolescent, 10-week old, male C57BL/6 mouse tibia to examine the skeletal response immediately prior to attainment of peak bone mass. Adaptation was quantified at the completion of either 2-week (n = 8) or 6-week (n = 12) loading terms by directly comparing volumetric bone mineral content between loaded and contralateral limbs by microcomputed tomography. The increase in mineral content was site specific with a greater response found in the corticocancellous proximal metaphysis (14%) than the cortical mid-shaft (2%) after 6 weeks of loading. Furthermore, bone volume fraction and average trabecular thickness of cancellous bone in the proximal tibia increased after 6 weeks by 15% and 12% respectively. Diaphyseal response was only evident proximal to the mid-shaft as indicated by an 8% increase in maximum principal moment of inertia. Both loading terms produced similar results for mineral content, volume fraction, and moments of inertia. Our finding that non-invasive loading increases the bone volume and fraction at a corticocancellous site by as much as 15% motivates exploring the use of mechanical loading to attain greater peak bone mass and inhibit osteoporosis.  相似文献   
997.
998.
BACKGROUND: Tumor-induced neovessel formation identified by gadolinium-enhanced magnetic resonance imaging (MRI) is a commonly used marker for breast malignancy. The purpose of this study was to assess possible differences in whole-breast vascularity as measured by contrast-enhanced MRI in the ipsilateral and contralateral breasts of patients with unilateral breast malignancies. METHODS: Gadolinium-enhanced MRI of the breast using a Siemens 1.0-T scanner with dedicated breast coil was performed on 22 consecutive patients with histologically confirmed unilateral breast carcinoma. Whole-breast vascularity of the breast containing the carcinoma was estimated as increased, decreased, or similar compared with the contralateral unaffected breast. Breast vascularity was then correlated to clinical factors including tumor size, histology, multifocality, nodal involvement, and patient age and menopausal status. RESULTS: Twenty patients had infiltrating carcinomas, and 2 patients had ductal carcinoma in situ. Four were multifocal. Fifteen of 22 patients demonstrated clear evidence of increased whole-breast vascularity in the ipsilateral breast containing the primary breast cancer compared with the contralateral breast. Although there was no clear correlation between the presence of increased whole-breast vascularity in the cancer-bearing breast with tumor size, histology, grade, mammographic appearance, or patient age and menopausal status, increased vascularity was present in 3 of 4 patients with multifocal disease and in 4 of 5 patients with metastatic disease in the axillary nodes. CONCLUSIONS: Measurable increases in whole-breast vascularity can be identified by contrast-enhanced MRI and appear with increased frequency in the cancer-bearing breast. These findings suggest that factors other than tumor size and histology may influence development of macroscopic vessels during tumor progression and may be indicative of angiogenic tumor biology.  相似文献   
999.
STUDY DESIGN: Random allocation of subjects into a placebo-controlled, crossover study. OBJECTIVES: To investigate the effect of changing thoracic and scapular posture on shoulder flexion and scapular plane abduction range of motion in asymptomatic subjects, and in subjects with subacromial impingement syndrome. BACKGROUND: Changes in upper body posture and concomitant imbalance of the muscle system have been proposed as one of the etiological mechanisms leading to subacromial impingement syndrome. Although clinicians commonly assess posture and devise rehabilitation programs to correct posture, there is little evidence to support this practice. METHODS AND MATERIALS: Selected postural, range of movement, and pain measurements were investigated in 60 asymptomatic subjects and 60 subjects with subacromial impingement syndrome, prior to and following thoracic and scapular taping intended to change their posture. RESULTS: Changing posture had an effect on all components of posture measured (P<.001) and these changes were associated with a significant increase (P<.001) in the range of motion in shoulder flexion and abduction in the plane of the scapula. Changing posture was not found to have a significant effect on the intensity of pain experienced by the symptomatic subjects, although the point in the range of shoulder elevation at which they experienced their pain was significantly higher (P<.001). CONCLUSIONS: The findings of this investigation suggest that changing 1 or more of the components of posture may have a positive effect on shoulder range of movement and the point at which pain is experienced.  相似文献   
1000.
PURPOSE: To determine whether innate visual-spatial ability influences medical student choice of a surgical career. In addition, the student's career interests on entering medical school (matriculation) predicted application and acceptance to a residency program. METHODS: Fifty-nine fourth year medical students at the University of Western Ontario completed a career choice questionnaire that identified the residency program(s) to which they showed interest at the time of matriculation, the program(s) to which they applied, and the residency program(s) to which they matched. The selections were compared with the student's score on the Vandenberg & Kuse Mental Rotations Test, a test of visual-spatial ability. RESULTS: Graduates initially interested in visual-spatially intense medical disciplines scored better (P < 0.02) on the Mental Rotations Test. The findings did not persist to the time of application and acceptance into residency training programs. There was no correlation between visual-spatial ability and selection of a visual-spatially intense specialty. Only 32% of graduates applied to their specialty of initial interest. CONCLUSION: The ability to rotate an object in three dimensions mentally does not to play an important role in surgical career selection although it was a predictor of initial career interest upon entry to medical school. Initial career interest was not an accurate predictor of career choice in general. In contrast to the overall results, 71% of individuals initially interested in family medicine ultimately applied to this medical discipline.  相似文献   
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