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71.
Cranial suture simulator for ultrasound diagnosis of craniosynostosis   总被引:1,自引:0,他引:1  
Background: In evaluating the effectiveness of ultrasound as a screening tool for craniosynostosis it was discovered that sonologists and sonographers needed more experience scanning and visualizing cranial sutures on ultrasound. Objective: To create an ultrasound simulator to train radiologists and technologists to locate and recognize patent and fused cranial sutures in children. Materials and methods: The hypoechoic appearance of patent sutures was simulated by cutting lines into life-sized plastic doll heads and filling them with a commercial hypoechogenic material. Fused hyperechoic sutures were simulated by not cutting into the hard plastic region of a suture. The simulators teaching value was evaluated on three radiology residents and three fellows. Subjects performed pre-training scans on unknown simulators, received feedback and an opportunity to scan a training simulator, and then performed post-training scans on random unknown simulators. Accuracy was recorded as percentage of correctly demonstrated sutures. Results: The suture simulator reproduces the sonographic appearance of patent and fused cranial sutures. Accuracy of acquisition, interpretation, and overall diagnosis increased from 64 to 91%, 79 to 91%, 61 to 97%, respectively, between pre and post training scans. Conclusion: An ultrasound simulator can reproduce the appearance of patent and fused cranial sutures in children and can be used to train radiologists and technologists in the performance of a screening protocol.  相似文献   
72.
Nearly 50,000 new cases of primary hyperparathyroidism (PHPT) are diagnosed annually in the United States. Most information about the disease focuses on the white population. We evaluated African American (AA) and white patients at our tertiary care university medical center to determine whether there was a racial difference in presentation of PHPT. A retrospective chart review of patients treated surgically for PHPT between 1997 and 2002 was performed. Demographic data, laboratory values, objective symptoms, surgical procedure, and histologic findings were recorded. The AA participants were matched to whites by age and gender. The effect of race was adjusted for the matching variables by including them in regression models. ANOVA chi2 tests were performed on the race effects. Thirty-six (14.4%) of the 286 patients treated for PHPT at Wake Forest University Baptist Medical Center during this 5-year period were AA. There was no difference in serum calcium or presence of objective symptoms, but PTH levels were significantly higher for blacks (207.5 vs 143.5 pg/mL; P = 0.02). In our study, AA patients had significantly higher parathyroid hormone levels at time of surgical intervention but did not present with a difference in symptoms or more advanced disease. Further research is recommended to characterize ethnic differences in patients with PHPT.  相似文献   
73.
The use of intercalary allografts has been an important innovation for use in limb-salvage surgery. However, the principal disadvantage of intercalary allografts is a high incidence of nonunion, fracture, and infection. With a recent trend toward higher doses of chemotherapy, an increased incidence of nonunion and healing problems can be anticipated with the use of allografts. In this article, the authors report two cases in which a vascularized fibula bone flap was used with an intercalary allograft, utilising an intramedullary approach, for immediate femur reconstruction following sarcoma resection. The rationale for this approach is to combine the mechanical strength of an allograft with the biologic activity of a vascularized bone flap. The allograft provides bone stock and early stability, while the addition of the vascularized bone flap substantially facilitates the host-allograft union.  相似文献   
74.
Catheterization is considered to be a mandatory procedure for adequate bladder drainage following an anti-incontinence operation until the recovery of normal voiding function occurs. We conducted this prospective study to challenge this practice. A total of 86 patients with genuine stress incontinence who underwent a modified Burch coplosuspension were randomized into two groups based on the day of operation. The study group consisted of 42 patients who had the transurethral Foley catheter removed postoperatively the next morning (Group A). The control group was composed of 43 patients who had the transurethral indwelling catheter left in place until the fifth postoperative day (Group B). The percentages of immediate voiding difficulties in Groups A and B were 7.1% and 0%, respectively (P >0.05). The postoperative urinary tract infection rates of Groups A and B were 16.6% and 23.3%, respectively (P >0.05). The success rates of our patients were not compromised after our modified operative procedures (78.6% with dry results and 19.0% with improved symptoms in Group A vs. 74.4% with dry results and 20.9% with improved symptoms in Group B, P >0.05). Our results imply that it is not necessary that an indwelling catheter, for bladder drainage, be left in place until the fifth postoperative day to prevent immediate voiding difficulties. Editorial Comment: The authors have performed a prospective randomized clinical trial of two different bladder management schemes involving a urethral catheter following a modified Burch colposuspension. Group A began their voiding trial on Day 1, Group B began their voiding trial on Day 5 after a 2-day clamped catheter bladder training program. Patients were not discharged until they had normal residuals (<100 ml). There were low, not statistically different, rates of immediate voiding difficulty in either group (7.1% vs. 0%) and therefore the only significant difference between the two groups was the length of hospitalization (5.3 days for Group A and 7.4 days for Group B). They conclude that it is not necessary for a urethral catheter to be left in for 5 days. Very few urogynecologists would disagree with this conclusion. The authors should be commended for performing a prospective randomized study of voiding trials. However, the relevance of this study to clinical practice is extremely limited since most urogynecologists do not perform urethral catheter clamping bladder training programs, nor wait 5 days to start a voiding trial  相似文献   
75.
IL-12 and IFN-gamma play key roles in murine lupus and planted antigen models of glomerulonephritis. However, their roles in renal organ-specific autoimmunity are unknown. To establish the roles of endogenous IFN-gamma and IL-12 in experimental autoimmune anti-glomerular basement membrane (GBM) glomerulonephritis (EAG), EAG was induced in normal C57BL/6 mice (WT), IL-12p40-deficient (IL-12p40-/-) mice, and IFN-gamma-deficient (IFN-gamma-/-) mice by immunization with alpha3-alpha5(IV)NC1 heterodimers. At 13 wk, WT mice developed EAG with linear mouse anti-GBM antibody deposition, histologic injury, proteinuria, and mild tubulointerstitial disease. Compared with WT mice, IL-12p40-/- mice had decreased histologic injury and trends to decreased leukocyte infiltrates. In contrast, 40% (4 of 10) of IFN-gamma-/- mice developed significant crescent formation and focal or diffuse interstitial infiltrates (WT, 0 of 8). Compared with WT and/or IL-12p40-/- mice, IFN-gamma-/- mice developed increased injury: histologic injury, total glomerular cell numbers, leukocytes in glomeruli, and renal expression of P-selectin and intercellular adhesion molecule 1. All groups developed similar serum anti-alpha3-alpha5(IV)NC1 antibodies and glomerular Ig deposition, but IFN-gamma-/- mice had decreased anti-alpha3-alpha5(IV)NC1 IgG2a. Therefore, IFN-gamma-/- mice developed increased cellular reactants despite a potentially less damaging antibody response. Dermal delayed-type hypersensitivity was increased in alpha3-alpha5(IV)NC1 immunized IFN-gamma-/- mice and was suppressed by recombinant murine IFN-gamma. CD4+ cells from draining nodes of immunized IFN-gamma-/- mice showed increased proportions of proliferating CD4+ cells but similar numbers of apoptotic cells. These studies demonstrate that in renal organ-specific autoimmunity, IL-12 is pathogenetic but IFN-gamma is protective. They lend weight to the hypothesis that depending on the context/severity of the nephritogenic immune response IFN-gamma has different effects.  相似文献   
76.
77.
Our study explored a largely unacknowledged obstacle to abortion access in Massachusetts: the unwillingness of nurses to staff abortion procedures. Evidence suggests that nurses tend to be more likely to oppose abortion than other medical professionals. However, the attitudes and practices of hospital-based nurses regarding abortion have not been thoroughly investigated. We collected qualitative information from physicians and nurse managers to understand how nurses' attitudes affect hospital-based abortion services in Massachusetts. We surveyed key respondents at all hospitals in Massachusetts where abortion services are available to any woman who requests them. Of the 20 individuals who responded (87%), 17 were physicians and 3 were nurse managers. We found that over half of physician respondents believed that the unavailability or unwillingness of nurses to staff abortions is a slight or moderate problem, and nearly a quarter of physician respondents characterized it as a large or very large problem. Thus, nurses' attitudes towards abortion and their unwillingness to assist with procedures may hinder patient access to abortion services.  相似文献   
78.
L-Theanine (delta-glutamylethylamide) is one of the predominant amino acids ordinarily found in green tea, and historically has been used as a relaxing agent. The current study examined the acute effects of L-theanine in comparison with a standard benzodiazepine anxiolytic, alprazolam and placebo on behavioural measures of anxiety in healthy human subjects using the model of anticipatory anxiety (AA). Sixteen healthy volunteers received alprazolam (1 mg), L-theanine (200 mg) or placebo in a double-blind placebo-controlled repeated measures design. The acute effects of alprazolam and L-theanine were assessed under a relaxed and experimentally induced anxiety condition. Subjective self-reports of anxiety including BAI, VAMS, STAI state anxiety, were obtained during both task conditions at pre- and post-drug administrations. The results showed some evidence for relaxing effects of L-theanine during the baseline condition on the tranquil-troubled subscale of the VAMS. Alprazolam did not exert any anxiolytic effects in comparison with the placebo on any of the measures during the relaxed state. Neither L-theanine nor alprazalam had any significant anxiolytic effects during the experimentally induced anxiety state. The findings suggest that while L-theanine may have some relaxing effects under resting conditions, neither L-theanine not alprazolam demonstrate any acute anxiolytic effects under conditions of increased anxiety in the AA model.  相似文献   
79.
OBJECTIVES: Sedentary behaviors have been correlated with obesity. We investigated whether changes in sedentary behaviors relate to changes in energy intake and/or physical activity. STUDY DESIGN: Experimental within-subject crossover design in which children participated in three 3-week phases: baseline and increased and decreased targeted sedentary behaviors. PARTICIPANTS: Thirteen 8- to 12-year-old, nonobese children. MEASUREMENTS: Sedentary behaviors were measured through the use of daily activity logs, physical activity measured with accelerometers, and energy intake measured by means of repeated 24-hour recalls collected during each phase. Energy intake, energy expenditure, and energy balance per day were calculated. RESULTS: Children showed significant (P <.001) increases of 50% and decreases of 53% in targeted sedentary behaviors from baseline during the increase and decrease phases, respectively. There was a significant (P =.05) increase in energy balance per day (+350.7 kcal) when sedentary behaviors were increased, as the result of an increase in energy intake per day (+250.9 kcal) and a decrease in energy expenditure (-99.8 kcal). No significant changes in energy balance were observed when sedentary behaviors were decreased. CONCLUSIONS: Increasing sedentary behaviors had a greater influence on physical activity and energy intake than reducing sedentary behavior in nonobese youth. In some children, changes in sedentary behaviors may be important to modify energy balance and prevent obesity.  相似文献   
80.
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