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31.
This paper presents a statistical analysis of the Canadian Chiropractic Examining Board results for the years 1977, 1978 and 1979. The examinations, of which there are 10, together with the overall result are examined from the point of view of the student’s college of graduation, the year in which the examinations were written and (for CMCC students only) prior non-chiropractic education. Finally the correlation between individual subjects and the final percent is discussed.It was found that both chiropractic college of graduation and the year in which the examinations were written were strongly related to an individual’s standing. Since it is quite possible that these results are an artifact of the examinations, arguments are put forward that the graduate population did indeed vary from year to year, and that systematic differences do exist among the graduates of the various colleges. On the other hand, however, it was found that prior non-chiropractic education had little bearing on how well a graduate did on the examinations.Although there were very strong correlations between the examinations and the final percent, four of these examinations — Neurology, Pathology, Physiology and Principles — together accounted for over 90% of the variance in the final grade.  相似文献   
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Introduction Few potentially curative treatment options exist besides resection for patients with very large (≥10 cm) hepatocellular carcinoma (HCC). We sought to examine the outcomes and risk factors for recurrence after resection of ≥10 cm HCC. Methods Perioperative and long-term outcomes were examined for 189 consecutive patients from 1993 to 2004 who underwent potentially curative resection of HCC ≥10 cm (n = 24; 13%) vs. those with HCC <10 cm (n = 165; 87%). Disease-free survival (DFS) and overall survival (OS) were determined by Kaplan–Meier analysis and patient, tumor, and treatment characteristics were compared using univariate and multivariate analysis. Results Median follow-up was 34 months. Tumors ≥10 cm were more likely to be symptomatic, of poorer grade, and have vascular invasion (p < 0.05). Twelve patients (50%) underwent an extended resection of more than four hepatic segments or resection of adjacent organs for oncologic clearance (diaphragm-2, inferior vena cava (IVC)-2, median sternotomy-1). Postoperative complications were more common after resection of >10 cm HCC (12/24, 50% vs. 35/165, 21%; p = 0.04). Median DFS was significantly shorter in patients with large HCC (≥10 cm) group compared to patients with smaller HCC (8.4 vs. 38 months; p = 0.001), but overall survival was not different between the two groups (5-year survival 54% vs. 53%; p = 0.43). Seventeen patients (71%) with very large HCC developed recurrences (12 intrahepatic, five systemic); eight of these patients (47%) underwent additional therapy (resection-4, TACE-3, RFA-1). Pathological positive margins and vascular invasion were significant determinants of DFS in tumors ≥10 cm (p < 0.05), but only vascular invasion was an independent risk factor for recurrence after multivariate analysis (HR 0.17; 95% CI: 0.04–0.8). Median OS after recurrence was 24 months. Conclusion Surgical resection is the optimal therapy for very large (≥10 cm) HCC. Although recurrences are common after resection of these tumors, overall survival was not significantly different from patients after resection of smaller HCC in this series. Presented at the 2006 American Hepato-Pancreatico-Biliary Congress, Miami, FL, March 9–12, 2006.  相似文献   
33.
BACKGROUND: Tumor number, size, and macrovascular invasion (MacroVI) are the most widely used predictors of survival after liver transplantation (LT) for hepatocellular carcinoma (HCC). We analyzed all patients undergoing LT for HCC at our center to establish the accuracy of preoperative clinical staging and to determine which patients have a higher probability of being understaged. METHODS: In all, 118 patients with confirmed HCC after LT from April 1991 to October 2004 at our institution were reviewed. All patients were monitored with serial imaging every 3 months to ensure their eligibility for LT within Milan criteria. Understaging in the 118 patients was defined as evidence on explant pathology that Milan criteria (TNM stage pT1 or pT2) had been exceeded. RESULTS: Five-year DFS was 78% with a recurrence rate of 15% after a median follow-up after LT of 30 months. On explant pathology, 43% (51/118) of patients exceeded Milan criteria and had a worse DFS (1 year, 95% vs. 87%; 3 year, 87% vs. 64%; P=0.03) compared to those who met LT criteria. Understaging was more likely in patients with imaging characteristics of > or = 2 tumor nodules (P=0.005) and tumor growth > 0.25 cm/month (P=0.02) and pathologic findings of vascular invasion (P=0.001) and bilobar tumors (P=0.002). CONCLUSIONS: Preoperative imaging every 3 months while on the waiting list frequently understages HCC as assessed by explant pathology. Recurrence after LT often occurred in patients that were understaged. Improving the accuracy of clinical staging and inclusion parameters will ensure proper organ allocation and acceptable outcomes after LT.  相似文献   
34.
BACKGROUND: Complete resection offers the only potential cure for ampullary carcinoma. We analyzed factors that contribute to treatment failure and survival in patients who underwent pancreaticoduodenectomy for ampullary carcinoma. STUDY DESIGN: We retrospectively reviewed all patients who underwent pancreaticoduodenectomy between August 1994 and August 2003 for ampullary carcinoma. Demographic, clinical, and pathologic data were collected. Chi-square analysis was used for categorical data and the t-test was used for continuous variables. Kaplan-Meier analyses were compared using the log-rank test to examine patient survival. RESULTS: Forty-three patients (24 men) aged 63.7 +/- 11.4 years (standard deviation) were followed for a mean of 23.9 months (median 660 days, range 18 to 2,249 days). Jaundice (n = 33) and weight loss (n = 13) were the most common presenting symptoms. Stage (p < 0.01) and degree of differentiation (p < 0.029) were significant predictors of failure by univariate analysis. But only stage (p < 0.04) was a significant predictor by multivariate analysis. Further analysis revealed that nodal status (p < 0.001), but not tumor grade, was a significant predictor of treatment failure. Neither demographic nor clinical variables were significant predictors. Five-year overall and disease-free survival rates were 67.4% and 51.4%, respectively. Both metastases and disease recurrence had significant impact on patient survival. CONCLUSIONS: Tumor stage is associated with treatment failure after pancreaticoduodenectomy for ampullary carcinoma and may identify candidates for adjuvant therapy. Because an aggressive surgical approach can be adopted safely with the best chance for cure, we recommend that pancreaticoduodenectomy be offered to all patients with ampullary tumors when malignancy or dysplasia is in question.  相似文献   
35.
BACKGROUND & AIMS: Pegylated interferon (IFN)-alpha plus ribavirin is the most effective treatment of chronic hepatitis C but has unpleasant side effects and high costs. A large proportion of patients do not respond to therapy for reasons that are unclear. We used gene expression profiling to investigate the molecular basis for treatment failure. METHODS: Expression profiling was performed on percutaneous needle liver biopsy specimens taken before therapy. Gene expression levels were compared among 15 nonresponder, 16 responder, and 20 normal liver biopsy specimens. Differential gene expression was confirmed using real-time polymerase chain reaction. RESULTS: We identified 18 genes whose expression differed significantly between all responders and all nonresponders (P < .005). Many of these 18 genes are IFN sensitive and 2 (ISG15/USP18) are linked in a novel IFN-regulatory pathway, suggesting a possible rationale for treatment resistance. Using a number of independent classifier analyses, an 8-gene subset accurately predicted treatment response for 30 of 31 patients. The classifier analyses were applicable to patients with genotype 1 infection and were not correlated with viral load, disease activity, or fibrosis. CONCLUSIONS: Hepatic gene expression profiling identified consistent differences in patients who subsequently fail treatment with pegylated IFN-alpha plus ribavirin: up-regulation of a specific set of IFN-responsive genes predicts nonresponse to exogenous therapy. These data may be of use in predicting clinical responses to treatment.  相似文献   
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37.

Objectives

To elucidate the impact of social support and its interrelations with other demand–control–support (DCS) model factors on presenteeism and absenteeism, and to determine which DCS factors were most influential.

Methods

Questionnaires from 2535 local government employees were analyzed. The Brief Job Stress Questionnaire (BJSQ) was used to assess DCS factors including job demand, job control, and social support from supervisors and coworkers. The Stanford Presenteeism Scale 13-item version (SPS-13) was used to evaluate both absenteeism (absent days) and presenteeism. For the latter, the Work Impairment Score (WIS) and the Work Output Score (WOS) were also used. Possible confounder-adjusted logistic and negative binomial regression analyses were performed to obtain odds ratios (ORs) for WIS and WOS and relative risks (RRs) for absenteeism according to DCS factors.

Results

Higher job control had a significantly protective effect on higher WIS in both males and females and a lower WOS in males. Based on a point estimate of an OR per 1 standard deviation change of each DCS factor, job control had the strongest effect on higher WIS in both males and females and a lower WOS in males. Higher job demand resulted in significantly higher ORs for both male and female WIS, and a lower WOS in females. Support from supervisors had a significantly protective effect on higher WIS in females and a lower WOS in males. Support from coworkers had a significantly protective effect on higher WIS in males. Higher support from coworkers had a significantly protective effect on absenteeism among both males and females, and higher job control had a significantly protective effect in females. The combination of high job strain and low support from supervisors had a significantly worsening effect, except for absenteeism in females. High job strain and low support from coworkers had a significantly worsening effect except for WOS in males.

Conclusions

The results suggest job control was the DCS factor most related to presenteeism. Higher support from supervisors and coworkers had a protective effect on presenteeism, and higher job demand had a worsening effect. Higher support from coworkers had a protective effect on absenteeism among both males and females. Interventions should focus on improving job control as a possible countermeasure to presenteeism, and encouraging support from coworkers as a possible countermeasure to absenteeism.
  相似文献   
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40.

Background

Over recent years there has been an increase in teaching of both palliative care and reflective practice in UK medical schools. The palliative care teaching at the University of Cambridge School of Clinical Medicine is multi-faceted and involves students writing reflective essays after individually meeting patients approaching the end of life during their final year general practice and hospital medicine placements. This paper draws on two studies examining this teaching element to analyse what the students found valuable about it and to comment on the practice of meeting patients and subsequent reflective writing.

Methods

Two studies have explored students’ perceptions of these course components. The first was a thematic analysis of 234 reflective essays from 123 students written in 2007-2008, including examining what students wrote about the exercise itself. The second project involved a semi-structured questionnaire that students completed anonymously; this paper reports on the free text elements of that study [sample size =107]. Since similar themes were found in both studies, the coding structures from each project were compared and combined, enabling triangulation of the findings around what the students found valuable from the palliative care teaching involving meeting patients and reflective writing.

Results

Overall, students reported that these components of the palliative care teaching are valuable. Four main themes were identified as aspects that students valued: (1) dedicated time with patients, (2) learning about wider elements of treatment and holistic care, (3) practicing communication skills, and (4) learning about themselves through reflective writing. Some students expressed a dislike for having to formally write a reflective essay.

Conclusion

It is possible to arrange for all of the medical students to individually meet at least two patients receiving palliative or end of life care. Students found these encounters valuable and many wrote about the benefit of formally writing about these experiences. Students reported finding this model useful in widening their skill-set and understanding of palliative care.
  相似文献   
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