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51.

Summary  

A diverse array of bone density, structure, and strength parameters were significantly associated with distal forearm fractures in postmenopausal women, but most of them were also correlated with femoral neck areal bone mineral density (aBMD), which provides an adequate measure of bone fragility at the wrist for routine clinical purposes.  相似文献   
52.

Background  

Balanced forces around the hip joint are critical for normal development of the hip joint, so it should be considered in every hip reconstructive procedure.  相似文献   
53.
54.
Bleeding during functional endoscopic sinus surgery (FESS) remains a challenge for both surgeons and anesthesiologists despite several modalities available for improving the surgical field. This study was conducted to evaluate the effect of oral clonidine premedication on blood loss and the quality of the surgical field in FESS. In a placebo-controlled clinical trial, a total of 84 American Society of Anesthesiologists (ASA) physical status I–II patients undergoing endoscopic sinus surgery for chronic sinusitis were randomly allocated to receive either oral clonidine 0.2 mg or identical-looking placebo tablets 90 min before arrival at the operating room. Blood loss in the clonidine group was 214 ± 67 ml on average and that in the placebo group was 276 ± 78 ml (mean ± SD, p < 0.01). The median (range) bleeding score in the clonidine group was significantly lower than that in the placebo group (2 (1–3) vs. 2.5 (2–4), p < 0.0001). Accordingly, the surgeon was more satisfied with the surgical field in the clonidine group than with that in the placebo group (median score, 4 (3–5) vs. 3 (1–5), p < 0.001). In conclusion, premedication with oral clonidine 0.2 mg can effectively reduce bleeding during FESS.  相似文献   
55.
Although the appendix has been recognized as a preferential site for carcinoid tumors in obese patients, no definitive guidelines are so far available regarding the management of these patients when candidates for bariatric surgery. This study was designed to fill that gap. Between 2000-2008, 558 patients underwent bariatric procedures. Appendectomy was routinely performed in 477 cases. Their charts were retrospectively retrieved and histopathology responses on surgical specimens were recorded. We aimed to assess: incidence of appendix carcinoid tumors (ACTs) and any possible risk-factor; modality of diagnosis (pre-, intra- or post-operatively); impact on the planned bariatric procedure; treatment reserved to such cases. Typical ACTs were diagnosed in 7 patients (1.4%) (median age: 33 years; median BMI: 49 kg/m2; males/females: 1/6). Four were diagnosed intra-operatively. Because of dimensions (<2 cm) and absence of mesoappendiceal or serosal involvement, simple appendectomy was performed during bariatric procedure, as planned. Three were diagnosed post-operatively (all <2 cm). In 1 case right hemicolectomy was performed 1 month later due to mesoappendiceal involvement. No appendectomy-related complication was encountered. All patients remained tumor-free during follow-up (mean: 64 months; range, 25-92). Young age, female sex, high BMI and diabetes mellitus resulted significantly associated with ACT. Our study sustains routine appendectomy or at least careful investigation of the appendix during bariatric surgery. For tumors <2 cm without mesoappendiceal or serosal involvement, simple appendectomy proved sufficient. Bariatric surgery did not have a negative effect on the treatment of malignancies that are discovered intra- or post-operatively.  相似文献   
56.

Background  

The application of endobiliary self-expandable metallic stents (SEMS) is considered the palliative treatment of choice in patients with biliary obstruction in the setting of inoperable malignancies. In the presence of SEMS, however, radical surgery is the only curative option when the resectability status is revised in case of malignancies or for overcoming complications arising from their application in benign conditions that masquerade as inoperable tumours. The aim of our study was to report our surgical experience with patients who underwent an operation due to revision of the initial palliative approach, whilst they had already been treated with biliary SEMS exceeding the hilar bifurcation.  相似文献   
57.
There remains little consensus on the link between vitamin levels and muscle mass or strength. We therefore investigated the association of serum 25-hydroxyvitamin D (25(OH)D), 1,25-dihydroxyvitamin D (1,25(OH)(2) D), and parathyroid hormone (PTH) levels with skeletal muscle mass and strength. We studied 311 men (mean age, 56 years; range, 23-91 years) and 356 women (mean age, 57 years; range, 21-97 years) representing an age-stratified, random sample of community adults. Multivariate linear regression models were used to examine the association of skeletal muscle mass (by total body dual-energy X-ray absorptiometry) and strength (handgrip force and isometric knee extension moment) with each of 25(OH)D, 1,25(OH)(2) D, and PTH quartiles, adjusted for age, physical activity, fat mass, and season. We found no consistent association between 25(OH)D or PTH and any of our measurements of muscle mass or strength, in either men or women. However, in subjects younger than 65 years, there was a statistically significant association between low 1,25(OH)(2) D levels and low skeletal mass in both men and women and low isometric knee extension moment in women, after adjustment for potential confounders. Modestly low 25(OH)D or high PTH levels may not contribute significantly to sarcopenia or muscle weakness in community adults. The link between low 25(OH)D and increased fall risk reported by others may be due to factors that affect neuromuscular function rather than muscle strength. The association between low 1,25(OH)(2) D and low skeletal mass and low knee extension moment, particularly in younger people, needs further exploration.  相似文献   
58.
STUDY OBJECTIVE: To determine if recommendations regarding perioperative beta-blocker therapy were followed by an increase in the number of eligible presurgical patients receiving beta-blockers and the number achieving the recommended heart rate (HR <60 beats per minute [bpm]). DESIGN: Retrospective, observational study. SETTING: Tertiary-care teaching hospital. MEASUREMENTS: The records of all 718 patients who underwent elective vascular surgery or coronary artery bypass grafting between January 2001 and March 2002 (pre-guideline) and those who did so between April 2002 and September 2003 (post-guideline) were reviewed. Percentage of eligible patients who received beta-blockers preoperatively and the target HR achieved in pre-guideline versus post-guideline patients were recorded. Differences were assessed using the unpaired t test and chi2 analysis. A P value of less than 0.05 is reported. MAIN RESULTS: Fifty percent of the post-guideline patients in the vascular surgery group were receiving beta-blockers at the time of preanesthetic evaluation versus 48% of pre-guideline patients (P = nonsignificant [NS]). Mean HR in the vascular surgery post-guideline beta-blocker group (70 +/- 14 bpm) was higher than in the pre-guideline beta-blocker group (65 +/- 11 bpm) (P < 0.01). Only 22% of those vascular surgery patients in the post-guideline group who were taking beta-blockers achieved the target HR of less than 60 bpm versus 29% of the vascular surgery patients taking beta-blockers in the pre-guideline group (P = NS). In the coronary artery bypass grafting group, 80% of post-guideline patients received beta-blocker before anesthesia assessment versus 75% of pre-guideline patients (P = NS). Mean HR in the post-guideline beta-blocker group (67 +/- 15 bpm) was similar to the pre-guideline beta-blocker group (64 +/- 13 bpm) (P = NS). Only 28% of the post-guideline patients who were receiving beta-blockers achieved the target HR of less than 60 bpm, which was not significantly different from the 17% achieved in the pre-guideline group (P = NS). CONCLUSION: At our institution, preoperative beta-blocker use was not significantly changed by publication of the recommendations.  相似文献   
59.

Background  

Veno-arterial extracorporeal membrane oxygenation (ECMO) is a common modality of circulatory assist device used in children. We assessed the outcome of children who had ECMO following repair of congenital cardiac defects (CCD) and identified the risk factors associated with hospital mortality.  相似文献   
60.
The expanded endonasal approach provides access to the entire ventral skull base for resection of neoplasms involving the skull base and brain. The creation of large defects of the bone and dura endoscopically presents unique reconstructive challenges. A layered reconstruction of the dura with inlay and onlay fascial grafts covered with fat grafts is an effective technique for repair. An intranasal balloon catheter is used to provide counterpressure in the early phase of healing and a lumbar spinal drain is a useful adjunct in patients at increased risk of a cerebrospinal fluid leak. Vascularized flaps may be necessary in some patients receiving radiation therapy. Continued advances in surgical technology and the introduction of new biomaterials will facilitate the reconstruction of skull base defects following endonasal brain surgery.  相似文献   
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