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681.

Background and objectives

A few recent epidemiological findings indicate a link between atherosclerosis and some lung functions. We studied further the relation between calcified chest atherosclerosis as seen in computed tomography (CT) and several lung functional parameters.

Patients and methods

Male construction workers originally screened for occupational lung cancer with CT had their chest atherosclerosis (aorta, the origins of its cervical branches, the coronary arteries and heart valves) visually classified. The relation between the atherosclerotic calcification scores and lung function (total lung capacity [TLC], forced expiratory volume in one second [FEV1%], forced vital capacity [FVC%], maximal expiratory flow when 50% of FVC remains to be exhaled, total and specific diffusing capacities; all above expressed as percent of predicted value, and the FEV1/FVC% ratio) were studied with the general linear model adjusted for smoking, exposure years for asbestos, and body mass index (n=432).

Results

All lung functions except TLC showed significant negative associations with calcifications in aorta and in its branches. TLC showed such association only with atherosclerosis in the ascending aorta.

Conclusions

Aortic atherosclerosis seems to be related with poor lung function. This may be due to deteriorated bronchial circulation, but other mechanisms can also be involved. Lung function poorer than would be expected due to pulmonary reasons may indicate aortic atherosclerosis.  相似文献   
682.
BACKGROUND: The effects of exercise training on myocardial substrate utilization have not previously been studied in patients with idiopathic dilated cardiomyopathy and mild heart failure. METHODS AND RESULTS: Myocardial glucose uptake was studied in 15 clinically stable patients with dilated cardiomyopathy (New York Heart Association class I-II, ejection fraction 34% +/- 8%) with the use of 2-[fluorine 18]fluoro-2-deoxy-d-glucose ([F-18]FDG) and positron emission tomography under euglycemic hyperinsulinemia. Eight of these patients participated in a 5-month endurance and strength training program, whereas seven patients served as nontrained subjects. Left ventricular function was assessed by 2-dimensional echocardiography before and after the intervention. After the training period, insulin-stimulated myocardial fractional [F-18]FDG uptake and glucose uptake rates were significantly increased in the anterior, lateral, and septal walls (P <.01) in the trained subjects but remained unchanged in the nontrained subjects. In the trained patients, whole-body insulin-stimulated glucose uptake was enhanced and serum free fatty acid levels were suppressed during hyperinsulinemia compared with the baseline study (P <.05). No changes were observed in the nontrained group. CONCLUSIONS: These results indicate that exercise training in patients with dilated cardiomyopathy improves insulin-stimulated myocardial glucose uptake. This improvement in glucose uptake may be indicative of a switch in myocardial preference to a more energy-efficient substrate.  相似文献   
683.
Antegrade intramedullary nailing with four different implants was used in 126 humeral shaft fractures. There were 74 acute fractures, 17 pathologic fractures, 16 fractures malaligned in a hanging cast or brace, 15 fractures with delayed union and 4 fractures that were nailed after failed open reduction and internal fixation. The nonunion rate was 21/95 after primary operation, and after reoperations 14/95. Distraction of the fracture was a significant cause of nonunion, but not type of fracture, localization, implant, and delay between injury and surgery. Shoulder joint function was significantly impaired in 25/67 patients. The patients regarded the result as good or satisfactory in 41/67 of the cases who were followed mean 3 (0.5-10) years.

We conclude that antegrade intramedullary nailing of humeral shaft fractures leads to a substantial risk of non-union and impairment of shoulder function. It can be recommended as primary treatment only when nonoperative treatment is likely to fail.  相似文献   
684.
    
Cellular oxygen sensing mechanisms have been linked to periodontal condition, and levels of haemoglobin (Hb) (the main carrier of oxygen) can be used as a surrogate measure for hypoxia. We aimed to examine relations between Hb levels and key periodontal health parameters in a general population.  相似文献   
685.

Objective

To examine the allelic diversity of structural, inflammatory, and matrix‐modifying gene candidates and their association with disc degeneration.

Methods

Subjects were 588 men ages 35–70 years. We investigated associations of single‐nucleotide polymorphisms in AGC1 and in 12 collagen, 8 interleukin, and 4 matrix metalloproteinase genes with quantitative magnetic resonance imaging measurements of disc desiccation and disc bulging and height narrowing scores, after controlling for age and suspected risk factors. Analyses were performed using QTDT software. P values were derived from 1,000 permutations, and empirical P values for global significance also were applied.

Results

Twelve of the 99 variants in 25 selected candidate genes provided evidence of association (P < 0.05) with disc signal intensity in the upper and/or lower lumbar regions. Allelic variants of AGC1 (rs1042631; P = 0.001), COL1A1 (rs2075555; P = 0.005), COL9A1 (rs696990; P = 0.00008), and COL11A2 (rs2076311; P = 0.018) genes provided the most significant evidence of association with disc signal intensity. The same variants of AGC1 (P = 0.010) and COL9A1 (P = 0.014), as well as variants in the COL11A1 gene (rs1463035 [P = 0.004]; rs1337185 [P = 0.015]) were also associated with disc bulging, as was AGC1 with disc height narrowing (rs1516797; P = 0.005). In addition, 4 allelic variants in the immunologic candidate genes (rs2071375 in IL1A [P = 0.027]; rs1420100 in IL18RAP [P = 0.005]) were associated with disc signal intensity.

Conclusion

Genetic variants account for interindividual differences in disc matrix synthesis and degradation. The accuracy of the quantitative disc signal intensity measurements we used likely enhanced our ability to observe these associations. Our findings shed light on possible mechanisms of degeneration and support the view that disc degeneration is a polygenetic condition.
  相似文献   
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