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41.
Bulletin of Environmental Contamination and Toxicology - Experiments were conducted to observe the role of plant growth promoting (PGP) strain PAW3 in reduction of Cr(VI) and cowpea growth. PAW3...  相似文献   
42.

Background

Current work hour restrictions and the expansion of requirements for surgery residents has led to decreased time on high-acuity rotations such as trauma and acute care surgery. In an effort to improve resident competency, we examined the efficacy of a new team-based trauma curriculum for postgraduate year 1 (PGY1) residents.

Methods

After completing required Advanced Trauma Life Support certification, PGY1s participated in a series of trauma simulations in 3-person teams from June to August. Scenarios were created to develop skills related to trauma management, teamwork, and communication. Each simulation was followed by video-based debriefing with a faculty facilitator. Clinical performance on a 1-month trauma rotation during the year was assessed by trauma faculty using a 24-item evaluation assessing management of acutely ill patients, leadership, communication, cooperation, and professionalism on a 1 (poor) to 5 (very effective) scale. Performance metrics of this intern class were compared with 2 years of previous cohorts who had not participated in any trauma-focused simulation curricula. One-way analysis of variance was used to examine differences in performance ratings across groups.

Results

The 2015 intern class (n?=?30) each participated in 6 scenarios during their first 2 months in residency. Trauma as intended specialty and performance on preinternship Advanced Trauma Life Support course were similar across 2013, 2014, and 2015 cohorts. Average performance on the trauma rotation was 3.55?±?0.56 for the 2013 cohort (n?=?11), 3.50?±?0.57 for the 2014 cohort (n?=?11), and 4.35?±?0.68 for the 2015 cohort (n?=?12). Post hoc analyses indicated no difference between means of the 2013 and 2014 cohort. However, the mean of the 2015 cohort was statistically significantly better than both the 2013 cohort (P?<?.01) and the 2014 cohort (P?<?.01).

Conclusion

Trauma-focused simulation improved PGY1 faculty ratings of performance in the clinical setting compared with previous cohorts with no such simulation experience. Adoption of these curricula is both feasible and beneficial.  相似文献   
43.
Prior to the introduction of cardioplegia, beating heart continuous coronary perfusion (BHCCP) was the only available method of myocardial protection. Currently, cardiac surgery on cardiopulmonary bypass with cardioplegic arrest is the gold standard strategy. Cardioplegic arrest provides an easier and safer way to operate on a still heart. It enables the performance of a broader range of cardiac procedures, and avoids the potential difficulties of continuous perfusion on a beating heart. Despite the overall effectiveness and safety of cardioplegia, some adverse effects remain, mainly due to the insult of ischemia, which results in ischemic reperfusion injury. As a result BHCCP has seen a revival as an alternative to cardioplegia for performing complex valvular surgery. Increasing experience reporting safety and efficacy of BHCCP is being published. However, despite the reported advantages, current available evidence validating safety and efficacy of BHCCP is controversial. This article provides an overview of BHCCP highlighting the current best available evidence supporting this strategy, concerns, controversies and potential areas for further research.  相似文献   
44.
BackgroundManagement of acute limb ischemia (ALI) is largely based on the etiology of arterial occlusion (embolic vs. thrombotic). To our knowledge, the ability of duplex scanning to differentiate embolic from thrombotic occlusion has not been previously reported.PurposeTo determine the ability of duplex scanning to differentiate embolic from thrombotic acute arterial occlusion.MethodsWe prospectively recruited 97 patients (50.3±19.7 years; 55% males) with 107 nontraumatic ALI in native arteries. All patients underwent surgical revascularization. Preoperative duplex scan detected arterial occlusion in the following arteries: iliac (11), femoral (38), popliteal (38), infrapopliteal (3), subclavian (3), axillary (1), brachial (9), and forearm arteries (4). We measured the arterial diameters at the site of occlusion (doccl) and at the corresponding contralateral healthy side (dCONTRA). The difference (Δ) between the two diameters was calculated as dOCCL?dCONTRA. Duplex scan was also used to assess the state of the arterial wall whether healthy or atherosclerotic and the presence of calcification or collaterals. According to surgical findings, limbs were classified into embolic (E group=55 limbs) and thrombotic (T group=52 limbs) groups.ResultsBoth groups were comparable regarding age, diabetes, hypertension, smoking, atrial fibrillation, and time of presentation. The status of arterial wall at the site of occlusion and presence of calcification or collaterals were all similar in both groups. Δ in the E group was 0.95±0.92 mm vs. ?0.13±1.02 mm in the T group (P<.001). A value of ≥0.5 mm for Δ had 85% sensitivity and 76% specificity for the diagnosis of embolic occlusion (CI 0.72–0.90, P<.001), whereas a value of less than ?0.5 mm for Δ had 85% sensitivity and 76% specificity for thrombotic occlusion (CI 0.72–0.90, P<.001).ConclusionIn acute arterial occlusion, ≥0.5 mm dilatation or diminution in the occluded artery diameter is a useful duplex sign for diagnosing embolic or thrombotic occlusion, respectively.  相似文献   
45.
Spontaneous coronary artery dissection (SCAD) is a relatively rare but important cause of acute coronary syndrome. The diagnosis is often made at autopsy. Risk factors include the peripartum period, oral contraceptive use, and atherosclerotic disease. SCAD must be considered every time a healthy young patient presents with an onset of acute myocardial ischemic syndrome. A timely diagnosis and intervention are mandatory as SCAD can cause sudden death. We describe two cases of SCAD, both treated successfully with emergency coronary artery bypass grafting using left internal mammary and radial arteries in the first case and the left internal mammary artery only for the second case.  相似文献   
46.
47.
This study examined the barriers and facilitators of HIV counseling, testing, and referral service (HIV CTR) acceptance among 278 youth aged 12-24 years old. Participants completed a questionnaire before health education sessions with trained counselors. Information was collected on individual characteristics, HIV testing acceptance, risk behaviors, reasons for having never been tested, and what would make it easier to get tested for HIV. Ninety percent of the respondents were minority and 52% were female with an average age of 15 years. High-risk minority youth who had never received HIV CTR listed low perception of risk and never having been offered a test as reasons for not having been tested. Increased availability of oral and rapid testing methods as well as free testing services were listed as facilitating their acceptance of HIV testing. Older youth aged 18-24 years reported that HIV tests in which results can be received rapidly and confidentially would encourage them to obtain HIV testing services. Early identification approaches should be tailored to increase the access to and acceptance of HIV-testing services among the adolescent and young adult populations.  相似文献   
48.
49.
BACKGROUND AND AIMS: Tegaserod is approved for the treatment of constipation-predominant irritable bowel syndrome (C-IBS) in females. The aim of this study was to evaluate the effect of tegaserod on colonic transit time (CTT) and symptoms in male patients with C-IBS. METHODS: Forty-four males with C-IBS (Rome II) were enrolled. After a baseline washout period of 2 weeks, 40 patients were randomized to 6 mg twice daily of tegaserod or placebo for 12 weeks. Daily bowel habits and weekly satisfactory relief of symptoms were recorded. Total and segmental CTT were measured using radiopaque markers at baseline and after treatment. RESULTS: The mean +/- SD for the total colonic, right colonic, left colonic and rectosigmoid transit time (in hours) were 18.96 +/- 3.92, 7.74 +/- 1.55, 5.64 +/- 1.51 and 5.58 +/- 2.2 in the tegaserod group compared to 22.47 +/- 3.73, 9.69 +/- 2.33, 6.6 +/- 1.32 and 6.18 +/- 2.22 in the placebo group at the end of 12 weeks. There was a statistically significant difference in the total, right and left CTT in the tegaserod group (P < 0.05) at the end of treatment. Global satisfactory relief at the end of 12 weeks was 75% in the tegaserod group and 50% in the placebo group (P > 0.05). Greater stool frequency occurred in the tegaserod group (P > 0.05). There was a significant decrease in the stool consistency at the end of 12 weeks in patients treated with tegaserod (P < 0.05). CONCLUSIONS: Tegaserod causes significant acceleration of CTT in male patients with C-IBS. Although there was a trend towards improvement in bowel symptoms in the treated group, this effect was not statistically significant.  相似文献   
50.
BACKGROUND: The outcome from small bowel transplantation (SBTx) has improved progressively over the past decade raising questions as to whether indications should be broadened from those currently followed based on "TPN (total parenteral nutrition) failure." OBJECTIVE AND METHODS: To assess current outcome, we studied the effect of transplantation on nutritional autonomy, organ function, and quality of life (QoL) measured by a validated self-administered questionnaire containing 26 domains and 130 questions, for a minimum of 12 months in a cohort of 46 consecutively transplanted patients between June 2003 and July 2004. The majority of transplanted patients (76%) had intestinal failure because of extreme short bowel, the remainder having either chronic pseudo-obstruction or porto-mesenteric vein thrombosis (PMVT). All but the PMVT patients were dependent on home TPN (HPN) (median 2, range 0-25 yr) and had developed serious recurrent infective complications with (25%) or without central vein thrombosis and liver failure. Sixty-one percent received a liver in addition to a small intestine. RESULTS: Follow-up was for a mean of 21 (range 12-36) months. Five patients died, two with chronic graft rejection. All the remaining patients have graft survival with an average of 1.2 (range 0-5) episodes of acute rejection. All patients were weaned from TPN by a median of 18 days (range 1-117 days) and from tube feeding by day 69 (range 22-272 days). There was a significant improvement in overall assessment of QoL and in 13 of 26 of the specific domains examined. CONCLUSION: Our results confirm the claim that a new era has dawned for SBTx, such that, with continued progress, it can potentially become an alternative to HPN for the management of permanent intestinal failure, rather than a last-chance treatment for "TPN failure."  相似文献   
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