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101.

Purpose

Video feedback and faculty feedback has been shown to improve surgical performance; however, consistent access to faculty is challenging. We studied the utility of structured peer-feedback (PF) compared to faculty-feedback (FF) during acquisition of basic and intermediate surgical skills.

Methodology

Two randomized non-inferiority trials were conducted with 1st (n?=?30) and 2nd year (n?=?29) medical students learning skin-lesion excision and closure (S), and single-layer hand-sewn bowel anastomosis (B), respectively. Five attempts were performed. PF participants used an Objective Structured Assessment of Technical Skills tool to guide feedback. Blinded raters assessed video-recorded performance, time and Integrity of the completed task were also assessed.

Results

For both tasks performance by PF was comparable to FF (P?=?0.111). Both groups improved significantly: performance (B:P?<?0.0001, S:P?=?0.035), time (B:P?=?0.043, S:P?<?0.0001) and integrity (B:P?<?0.0001, S:P?<?0.032).

Conclusion

Structured peer-feedback is equivalent to faculty-feedback in the acquisition of basic and intermediate surgical skills, giving students freedom to practice independently.  相似文献   
102.
Background and Aim: The relationship between age and esophageal motility parameters (i.e. basal and residual pressure of the lower esophageal sphincter [LES]) remains to be established in achalasia patients, possibly because most previous studies did not distinguish between classic and vigorous achalasia patients. We investigated the relationship between age and esophageal motility parameters in both classic and vigorous achalasia patients. Methods: A retrospective review of esophageal manometry data in a single center was undertaken. Basal and residual pressure for LES was analyzed. A total of 103 achalasia patients were enrolled, comprising 84 classic and 19 vigorous types. They were subdivided into three different age groups as follows: 21–40 years old (group A), 41–60 years old (group B), and over 60 years old (group C). Results: In classic achalasia patients (M : F = 27:57, mean age = 44 ± 15 years old) the older age group showed a significantly higher basal LES pressure (49.62 ± 19.63 mmHg) than the younger age group (P < 0.0001). Moreover, the older age group also showed significantly high residual LES pressure (20.46 ± 8.61 mmHg) than the younger age group (P = 0.0006). In contrast, in vigorous achalasia patients (M : F = 12:7, mean age: 47 ± 15 years old) there were no difference between age and motility indices (all P > 0.05). Conclusion: In classic achalasia patients there appears to be a correlation between age and esophageal motility indices, especially basal and residual LES pressure. Such correlations do not appear to exist for vigorous achalasia patients.  相似文献   
103.
Immunosuppressive therapy (IST) has provided an alternative treatment option for cure of aplastic anemia patients who cannot receive bone marrow transplantation. Although there have been many recent studies on the efficacy of antithymoglobulin (ATG) combined with cyclosporine A (CsA), there is no data on the correlation between the variability of CsA levels and the response to IST. Therefore, we retrospectively assessed the factors associated with IST efficacy in patients with acquired severe aplastic anemia (SAA). Sixty‐six patients were treated with ATG combined with CsA for 6 months. In the response group, the CsA levels were increased rapidly to more than 200 ng/mL within the first 2 wk after starting the IST. However, the non‐response group had a pattern of slower increase of the CsA levels. The CsA levels, during the first and second week of treatment with IST, were significantly different in the responders and non‐responders. The factors predictive of response to IST and survival were analyzed. The univariate analysis showed that a younger age at the initiation of IST, a high absolute neutrophil count prior to starting IST, a short interval between the diagnosis and initiation of IST, and high CsA levels during the first and second week of IST treatment were positively associated with the response rate and overall survival. The multivariate analysis showed that these four factors were independent factors associated with a longer patient survival. A high response rate was associated with a short interval between diagnosis and initiation of IST as well as high CsA levels during the first and second week of IST. Therefore, early intensification of CsA levels might improve patient outcome.  相似文献   
104.
105.

BACKGROUND:

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is the leading reason for hospitalization in Canada and a significant financial burden on hospital resources. Identifying factors that influence the time a patient spends in the hospital and readmission rates will allow for better use of scarce hospital resources.

OBJECTIVES:

To determine the factors that influence length of stay (LOS) in the hospital and readmission for patients with AECOPD in an inner-city hospital.

METHODS:

Using the Providence Health Records, a retrospective review of patients admitted to St Paul’s Hospital (Vancouver, British Columbia) during the winter of 2006 to 2007 (six months) with a diagnosis of AECOPD, was conducted. Exacerbations were classified according to Anthonisen criteria to determine the severity of exacerbation on admission. Severity of COPD was scored using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. For comparative analysis, severity of disease (GOLD criteria), age, sex and smoking history were matched.

RESULTS:

Of 109 admissions reviewed, 66 were single admissions (61%) and 43 were readmissions (39%). The number of readmissions ranged from two to nine (mean of 3.3 readmissions). More than 85% of admissions had the severity of COPD equal to or greater than GOLD stage 3. The significant indicators for readmission were GOLD status (P<0.001), number of related comorbidities (OR 1.47, 95% CI 1.10 to 1.97; P<0.009) and marital status (single) (OR 4.18, 95% CI 1.03 to 17.02; P<0.046). The requirement for social work involvement during hospital admission was associated with a prolonged LOS (P<0.05).

CONCLUSIONS:

The results of the present study show that disease severity (GOLD status) and number of comorbidities are associated with readmission rates of patients with AECOPD. Interestingly, social factors such as marital status and the need for social work intervention are also linked to readmission rates and LOS, respectively, in patients with AECOPD.  相似文献   
106.
107.
BACKGROUND: Vascular endothelial growth factor-C (VEGF-C) is a specific growth factor of lymphatics, which is known to play some role in tumor growth and metastasis to lymph nodes and distant organs in various malignancies. The purpose of the present study was to investigate the expression of VEGF-C in human esophageal squamous cell carcinomas (ESCC) to elucidate its role in tumor progression and lymph node metastasis. Another aim of the study was to investigate the relation between VEGF-C and cyclooxygenase-2 (COX-2) in ESCC. METHODS: The expression of VEGF-C and COX-2 in ESCC was evaluated in 13 endoscopic mucosal resection specimens and in 21 surgical specimens by immunohistochemical staining. Clinical data were obtained from medical records. RESULTS: The degree of VEGF-C expression increased as the depth of primary tumor progressed (r = 0.521, P = 0.002), the stage progressed (r = 0.572, P < 0.001), and the degree of COX-2 expression increased (r = 0.387, P = 0.024). The VEGF-C positive rate was different between early cancers in which regional lymph node metastasis was thought to be absent and advanced cancers in which regional lymph node metastases were confirmed after surgery (20.0% vs 100.0%; P < 0.001). CONCLUSIONS: The VEGF-C expression in ESCC is related to COX-2 expression, and VEGF-C is also associated with the depth of primary tumor, the stage, and probably lymph node metastasis. Thus the investigation of VEGF-C expression in ESCC may assist in management planning.  相似文献   
108.
Aims To determine relationships between drug use ‘hardness’ (defined in increasing order of hardness as no drug use, marijuana use, non‐injected heroin or cocaine use, crack smoking and injection drug use) and prevalences of several sexually transmissible infections among young adults in a high‐risk neighbourhood. Drug users, particularly injection drug users and crack smokers, may be a core group for some sexually transmitted infections. Design Cross‐sectional survey and assays of young adults from (a) a household probability sample and (b) a targeted sample of youth who have used injected drugs, crack, other cocaine or heroin. Setting Bushwick, an impoverished New York City minority neighbourhood with major drug markets. Participants A total of 363 18–24‐year‐olds from a household probability sample; 165 Bushwick 18–24‐year‐olds who have used injected drugs, crack, other cocaine or heroin. Measurements Drug use by self‐report; serum‐ and urine‐based assays for HIV, hepatitis B and C, syphilis, gonorrhoea, chlamydia and herpes simplex (type 2). Findings Household‐sample prevalences: HIV, hepatitis C and syphilis, 1%; gonorrhoea 3%; chlamydia 5%; past or present hepatitis B infection 8%; herpes simplex (type 2) 18%. In combined household and targeted samples, hepatitis C and HIV were concentrated among drug injectors. Herpes simplex (type 2), syphilis and hepatitis B increased among women with ‘hardest drug ever used’. Conclusions Using ‘harder’ drugs is associated with some but not all of these infections. Prevention efforts should help youth avoid unsafe sex and higher‐risk drugs.  相似文献   
109.
Fetal hemoglobin (HbF) decreases polymerization of sickle hemoglobin (HbS) and improves outcomes in sickle cell disease (SSD). Therefore, a therapeutic goal in SSD is pharmacologic reactivation of HbF. Silencing of the gamma-globin (HbF) gene is associated with DNA methylation. The cytosine analog 5-aza-2'-deoxycytidine (decitabine) hypomethylates DNA by inhibiting DNA methyltransferase. We examined if subcutaneous decitabine could increase HbF levels and improve SSD pathophysiology without cytotoxicity. Eight symptomatic SSD patients resistant or intolerant of standard treatment with hydroxyurea received decitabine 0.2 mg/kg subcutaneously 1 to 3 times per week in 2 cycles of 6-week duration. Treatment decreased neutrophils and increased mean HbF (6.5% to 20.4%, P <.0001) and mean total hemoglobin (76 to 96 g/L [7.6 to 9.6 g/dL], P <.001). Features of vaso-occlusive crisis pathophysiology such as red cell adhesion, endothelial damage, and coagulation pathway activity significantly improved. gamma-Globin gene promoter methylation decreased, and platelets and the proportion of megakaryocytes and erythroid cells in the marrow increased without a decrease in marrow cellularity, consistent with a DNA hypomethylating, noncytotoxic mechanism of action. Weekly subcutaneous decitabine produces cumulative increases in HbF and total hemoglobin through a noncytotoxic mechanism of action. Chronic dosing and sustained increases in hemoglobin F and total hemoglobin levels may be possible. Further studies in SSD and thalassemia are indicated.  相似文献   
110.
OBJECTIVES: The significance of genetic polymorphisms in the development of Paget's disease of bone is unclear at present. METHODS: We analysed the BsmI polymorphism of the vitamin D receptor (VDR) gene, the PvuII and XbaI polymorphisms of the oestrogen receptor-alpha (ER alpha) gene, and the A986S polymorphism of the calcium-sensing receptor (CaSR) gene in 69 pagetic patients and 120 healthy subjects. We also examined the relationship of these polymorphisms with lumbar spine and femoral neck BMD as well as with biochemical parameters (serum alkaline phosphatase, osteocalcin and parathyroid hormone) in Paget's disease. RESULTS: The XbaI and PvuII genotype distributions of the ER alpha gene were significantly different between patients with Paget's disease and control subjects (P<0.001). Also, the CaSR A986S genotype frequency was significantly different between pagetic patients and controls (P<0.01). No significant effect of gene polymorphisms on BMD or biochemical parameters of bone turnover was observed. CONCLUSION: Our results suggest that the ER alpha PvuII/XbaI and CaSR A986S polymorphisms may contribute to genetic susceptibility to Paget's disease. However, further studies are required to investigate the underlying pathomechanism and to replicate the associations.  相似文献   
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