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Summary The influence of the palatal vault dimensions on tongue position is here studied through evaluation of the in‐mouth air cavity (IMAC) volume when the mandible is in maximal intercuspal position. A sample of 35 women (mean age 21·2 ± 1·0) and 15 men (mean age 22·1 ± 0·9) was selected. The sagittal cross‐section area of the IMAC, which is modulated by the tongue position, was measured on lateral cephalograms. Dental casts were used to measure the palatal vault volume, which was defined by the occlusal plane, the hard palate and the posterior face of the second molars. Palatal vault volume allowed deduction of the IMAC volume through a rule of three procedure relating volume to area ratios. No IMAC could be calculated from cephalograms of 10 subjects who had the tongue stuck to the palate. For the 40 other subjects, the IMAC volume was 8·9 ± 4·8 mL. It was 2 mL larger in men (n = 14) than in women (n = 26) and was the largest in skeletal Class III and the smallest in skeletal Class II (P > 0·05). IMAC volume was strongly correlated with palatal vault height but neither with palatal width nor length. It was thus assumed that the height of the palatal vault could influence the most observed position of the tongue but this does not exclude a possible growth influence of the tongue on its surrounding skeletal structures.  相似文献   
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BACKGROUND: In the general population, obesity is associated with increased risk of adverse outcomes. However, studies of patients with chronic disease suggest that overweight and obese patients may paradoxically have better outcomes than lean patients. We sought to examine the association of body mass index (BMI) and outcomes in stable outpatients with heart failure (HF). METHODS: We analyzed data from 7767 patients with stable HF enrolled in the Digitalis Investigation Group trial. Patients were categorized using baseline BMI (calculated as weight in kilograms divided by the square of height in meters) as underweight (BMI <18.5), healthy weight (BMI, 18.5-24.9, overweight (BMI, 25.0-29.9), and obese (BMI > or =30.0). Risks associated with BMI groups were evaluated using multivariable Cox proportional hazards models over a mean follow-up of 37 months. RESULTS: Crude all-cause mortality rates decreased in a near linear fashion across successively higher BMI groups, from 45.0% in the underweight group to 28.4% in the obese group (P for trend <.001). After multivariable adjustment, overweight and obese patients were at lower risk for death (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.80-0.96, and HR, 0.81; 95% CI, 0.72-0.92, respectively), compared with patients at a healthy weight (referent). In contrast, underweight patients with stable HF were at increased risk for death (HR 1.21; 95% CI, 0.95-1.53). CONCLUSIONS: In a cohort of outpatients with established HF, higher BMIs were associated with lower mortality risks; overweight and obese patients had lower risk of death compared with those at a healthy weight. Understanding the mechanisms and impact of the "obesity paradox" in patients with HF is necessary before recommendations are made concerning weight and weight control in this population.  相似文献   
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A 48‐year‐old male patient with long‐standing ulcerative colitis since February 2001 which was diagnosed by endoscopy, developed acute digital ischemia affecting both hands with fixed colour changes in the left index finger which was followed shortly by digital ulceration. Magnetic resonance angiography (MRA) of both upper limbs showed evidence of vasculitis affecting digital arterioles on both sided and right subclavian occlusion. The patient received pulse methylprednisolone followed by cyclophosphamide pulse therapy, the latter continuing on a monthly basis for 6 months with appreciable improvement and remission of the vasculitic process; follow‐up MRA showed reperfusion of the previously occluded subcalvian artery. To the authors’ knowledge vasculitis complicating the course of ulcerative colitis is a rare association and is only sporadically reported in the literature. This rare entity should be diagnosed early and aggressively treated; MRA is a very promising diagnostic tool that is suitable for both diagnosis and follow‐up of patients with this rare entity.  相似文献   
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A 58-year-old man with an implanted minute ventilation rate adaptive DDD pacemaker underwent RF ablation of the AV junction because of symptomatic supraventricular tachyarrhythmias. Immediately after ablation, while the pacemaker was programmed in the DDDR mode, AV sequential pacing at upper rate was observed. After programming the pacing system to the DDD mode and repeated ablation, no abnormalities were observed. It was concluded that AV sequential upper rate pacing was caused by false interpretation of the RF current by the sensor measuring transthoracic impedance as an indicator for minute ventilation.  相似文献   
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Cytokine generation in stored platelet concentrates   总被引:9,自引:0,他引:9  
BACKGROUND: Cytokines, because of the nature of their immunoinflammatory actions, are potential mediators of the symptom complex of nonhemolytic transfusion reactions. One possible source of cytokines in the transfusion setting is the stored blood component itself. STUDY DESIGN AND METHODS: To test this possibility, the plasma portion of stored platelet concentrates (PCs) was assayed for the presence of interleukins 1 beta (IL-1 beta), 6 (IL-6), and 8 (IL-8) and tumor necrosis factor alpha (TNF-alpha). Samples were taken from PCs obtained from the inventory of a regional blood center (n = 120; 30 each of 2-, 3-, 4-, and 5-day-old units). RESULTS: Detectable levels of IL-8 were measured in 59 percent of the PCs sampled, ranging from 30 percent of the 2-day-old units to 83 percent of the 5-day-old units. The median IL-8 concentration ranged from undetectable levels in 2-day- old units up to 1100 pg per mL in 5-day-old units. The mean IL-8 concentration in 5-day-old units, 11,600 pg per mL, was 100 times the mean for 2-day-old units, which was 116 pg per mL (p < 0.0001). The highest levels of IL-8, 50,000 to 200,000 pg per mL, in general were found in units with the longest storage times and highest white cell counts. Sequential sampling of 17 individual PCs over 7 days of storage confirmed that IL-8 increases progressively with increasing storage time. Parallel, but smaller, increases in IL-1 beta were observed in those units with high IL-8 concentrations. TNF-alpha was detected in 3 (10%) of 30 five-day-old PCs, but never exceeded 55 pg per mL in any unit tested. IL-6 at levels of 740 and 508 pg per mL was detected in two 5-day-old units with high white cell counts of 9500 and 14,800 per microL, respectively, but not in 21 additional units tested with white cells < or = 9200 per microL or storage time of < or = 2 days. White cell reduction by third-generation filters on Day 1 of platelet storage prevented the generation of IL-8 and IL-1 beta to Day 5 of storage. CONCLUSION: Although IL-8 achieved levels in some units of PCs that appear capable of causing physiologic changes, the potential adverse effect on transfusion recipients of the infusion of cytokines in PCs remains to be investigated.  相似文献   
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