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61.
OBJECTIVE: It has been suggested that non-invasive aortic stiffness measurements can be used as an indicator of atherosclerosis. The relationships of arterial stiffness with arterial wall hypertrophy and atherosclerosis however, have rarely been investigated in large-scale studies. The present study reports the associations of carotid arterial structure assessed by B-mode ultrasound with carotid-femoral pulse-wave velocity in hypertensive and non-hypertensive subjects. DESIGN AND METHODS: Free health examinations were performed on 564 subjects (age 58.2 +/- 10.8 years, 31.9% of women, 53.2% of all were hypertensive). Carotid-femoral pulse-wave velocity (PWV) was used to assess aortic stiffness. Carotid ultrasound examination included measurements (at sites free of plaques) of intima-media thickness (IMT) at the common carotid arteries (CCA), CCA-lumen diameter, and assessment of atherosclerotic plaques in the extracranial carotid arteries. RESULTS: Subjects with carotid plaques had significantly higher mean sex-adjusted values of PWV than those without carotid plaques (12.7 +/- 0.2 versus 11.1 +/- 0.1 m/s, P < 0.001). Multivariate analyses showed that this association was independent of sex, age, height, body mass index, mean blood pressure, pulse pressure, diabetes, hypercholesterolaemia and smoking habits (P < 0.009). PWV was positively associated with CCA-IMT and CCA-lumen diameter in sex-adjusted analysis (partial correlation coefficients (r ) were respectively 0.39 and 0.42, P < 0.001 for each). However, the association of PWV with CCA-IMT, but not that with CCA-lumen diameter, disappeared after further adjustment for age and blood pressure measurements (mean blood pressure and/or pulse pressure). CONCLUSION: This study shows that there is a differential association of PWV with CCA-IMT and carotid plaques. The nature of the independent positive association between atherosclerosis and arterial stiffness should be thoroughly investigated.  相似文献   
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Galli  SJ; Arizono  N; Murakami  T; Dvorak  AM; Fox  JG 《Blood》1987,69(6):1661-1666
The normal skin and other tissues of adult mast cell-deficient WBB6F1- W/Wv or WCB6F1-Sl/Sld mice contain less than 1.0% the number of mast cells present in the corresponding tissues of the congenic normal (+/+) mice. As a result, genetically mast cell-deficient WBB6F1-W/Wv or WCB6F1-Sl/Sld mice are widely used for studies of mast cell differentiation and function. We found that mast cells developed at sites of idiopathic chronic dermatitis in WBB6F1-W/Wv mice and that the number of mast cells present in the skin of WBB6F1-W/Wv mice was proportional to the severity of the dermatitis (in ear skin, there were 33 +/- 4 mast cells/mm2 of dermis at sites of severe dermatitis v 9 +/- 3 at sites of mild dermatitis, 0.8 +/- 0.3 in skin without dermatitis, and 100 +/- 7 in the normal skin of congenic WBB6F1-+/+ mice; in back skin, the corresponding values were 2.0 +/- 0.6, 1.1 +/- 0.9, 0.025 +/- 0.025, and 26.2 +/- 3.2). The development of mast cells was a local, not systemic, consequence of the dermatitis. Thus, WBB6F1-W/Wv mice with severe dermatitis lacked mast cells in skin not showing signs of dermatitis and also in the peritoneal cavity, stomach, cecum, and tongue. Idiopathic chronic dermatitis was not associated with the local development of mast cells in WCB6F1-Sl/Sld mice, a mutant whose mast cell deficiency is due to a mechanism distinct from that of WBB6F1-W/Wv mice. These findings may have implications for understanding the nature of the mast cell deficiency in WBB6F1-W/Wv and WCB6F1-Sl/Sld mice and for the use of these mutants to analyze mast cell differentiation and function.  相似文献   
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Background:

Undergraduate surgery is at an important crossroads. Many departments report significant difficulties delivering effective teaching. Our student feedback indicated a dated surgical curriculum lacking structure, quality and uniformity. We report on a new ”blended” approach employing a combination of professional DVDs, case based discussions, online material and traditional bedside teaching designed to provide structure, standardization, and equality of learning .

Methods:

Year 4 students who had undertaken the new course and year 5 students who had participated in the traditional teaching programme were compared. Students completed a 20 item questionnaire about their experiences of the surgical teaching programme.

Results:

One hundred and seventy-one year 4 (70%) and148 year 5 students (66%) responded. Domains relating to “Overall Satisfaction with the course”, “Approval of innovative teaching methods and interactivity” and “Satisfaction with the clarity of course information” showed improvements when comparing the new and old programmes. However bedside teaching was not rated as highly in the new programme (p<0.05).

Conclusion:

This blended approach has resulted in improved student understanding and engagement. The apparent compromise of bedside teaching may be a reflection of higher expectations. We believe that a similar blended approach has the potential to re-invigorate surgical teaching elsewhere.  相似文献   
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OBJECTIVE

Clinical guidelines recommend point-of-care glucose testing and the use of supplemental doses of rapid-acting insulin before meals and at bedtime for correction of hyperglycemia. The efficacy and safety of this recommendation, however, have not been tested in the hospital setting.

RESEARCH DESIGN AND METHODS

In this open-label, randomized controlled trial, 206 general medicine and surgery patients with type 2 diabetes treated with a basal-bolus regimen were randomized to receive either supplemental insulin (n = 106) at bedtime for blood glucose (BG) >7.8 mmol/L or no supplemental insulin (n = 100) except for BG >19.4 mmol/L. Point-of-care testing was performed before meals, at bedtime, and at 3:00 a.m. The primary outcome was the difference in fasting BG. In addition to the intention-to-treat analysis, an as-treated analysis was performed where the primary outcome was analyzed for only the bedtime BG levels between 7.8 and 19.4 mmol/L.

RESULTS

There were no differences in mean fasting BG for the intention-to-treat (8.8 ± 2.4 vs. 8.6 ± 2.2 mmol/L, P = 0.76) and as-treated (8.9 ± 2.4 vs. 8.8 ± 2.4 mmol/L, P = 0.92) analyses. Only 66% of patients in the supplement and 8% in the no supplement groups received bedtime supplemental insulin. Hypoglycemia (BG <3.9 mmol/L) did not differ between groups for either the intention-to-treat (30% vs. 26%, P = 0.50) or the as-treated (4% vs. 8%, P = 0.37) analysis.

CONCLUSIONS

The use of insulin supplements for correction of bedtime hyperglycemia was not associated with an improvement in glycemic control. We conclude that routine use of bedtime insulin supplementation is not indicated for management of inpatients with type 2 diabetes.  相似文献   
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