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101.

Background

We report the utility of combining lung sound analysis and fractional exhaled nitric oxide (FeNO) for phenotype classification of airway inflammation in patients with bronchial asthma.We investigated the usefulness of the combination of the expiration-to-inspiration sound power ratio in the mid-frequency range (E/I MF) of 200–400 Hz and FeNO for comprehensively classifying disease type and evaluating asthma treatment.

Methods

A total of 233 patients with bronchial asthma were included. The cutoff values of FeNO and E/I MF were set to 38 ppb and 0.36, respectively, according to a previous study. The patients were divided into 4 subgroups based on the FeNO and E/I MF cutoff values. Respiratory function, the percentages of sputum eosinophils and neutrophils, and patient background characteristics were compared among groups.

Results

Respiratory function was well controlled in the FeNO low/E/I MF low group (good control). Sputum neutrophil was higher and FEV1,%pred was lower in the FeNO low/E/I MF high group (poor control). History of childhood asthma and atopic asthma were associated with the FeNO high/E/I MF low group (insufficient control). The FeNO high/E/I MF high group corresponded to a longer disease duration, increased blood or sputum eosinophils, and lower FEV1/FVC (poor control).

Conclusions

The combination of FeNO and E/I MF assessed by lung sound analysis allows the condition of airway narrowing and the degree of airway inflammation to be assessed in patients with asthma and is useful for evaluating bronchial asthma treatments.  相似文献   
102.
To better understand the effects of high-altitude hypoxia on cardiac performance, healthy lowlandresiding volunteers were studied in 2 groups: 10 subjects after acute ascent to 12,500 ft (3,810 m) (acute group) and 9 subjects after chronic exposure for 6 weeks to 17,600 ft (5,365 m) and 11,000 ft (3,353 m) (chronic group). Systolic time intervals and M-mode echocardiograms were recorded at low and high altitudes. Heart rate was 21% greater at high altitude for all subjects. Preejection period/left ventricular ejection time (PEP/LVET) increased by 16% in the acute group and by 22% in the chronic group. Heart size was smaller at high altitude in both groups, with left atrial and left ventricular (LV) diameters decreasing by 10 to 12%. These changes were statistically significant (p ≤ 0.01). Despite the increase in PEP/LVET, echocardiographic measurements of LV function (percent fractional shortening and mean normalized velocity of circumferential fiber shortening) remained normal. LV isovolumic contraction time was shorter at high altitude, suggesting heightened, rather than depressed, contractility. LV function does not appear to deteriorate at high altitude. Alterations in systolic time intervals probably result from decreased preload, as reflected by smaller heart size, rather than from heart failure or depressed LV contractility.  相似文献   
103.
Peripheral muscle responsiveness to insulin was studied in neonatal rats in vivo by measuring net incorporation of radiolabeled glucose to glycogen in diaphragm. D(U-14C) glucose, 0.03 μCi/g rat pup weight, was injected i.p. with or without (control) insulin 5000 μU/g rat pup weight into pups from 86 litters of Sprague-Dawley rats as well as into 16 adult rats by the technique of Rafaelson. Diaphragms were excised after a 30-min in vivo exposure at birth, 24, 48, 72, or 168 hr of age and in the adult rats. Insulin increased net incorporation of radiolabeled glucose into diaphragm glycogen in comparison to age-matched controls (p < 0.025). The percent stimulation by insulin of labeled glucose into diaphragm glycogen was low at birth (250%) and at 24 hr (200%), but increased with advancing age and approached adult levels by 168 hr (1270%). At birth and at 24 hr, a 5-log insulin dose-response curve showed significant net incorporation only at 5000 μU insulin/g rat pup weight; by 72 hr a significant increase was noted at 50 μU insulin/g rat pup weight. Muscle glycogen concentration was high at birth (1.22 mg100 mg tissue), fell to 50% of the birth value from 24 through 168 hr, and could not account for the decreased insulin response noted. Decreased uptake of deoxyglucose into diaphragm in vivo paralleled the reduced net incorporation of radiolabeled glucose into diaphragm glycogen during the time period studied. The data are interpreted to indicate a blunted responsiveness of skeletal muscle to insulin during the first 48 hr in rats, which is related to decreased sensitivity of hexose transport to insulin.  相似文献   
104.
目的研究呼吸纯氧对健康人听感觉门控P50的影响。方法右利手、健康男性大学生志愿者28名,根据随机数字表分为对照组(n=12)和实验组(n=16)。佩戴面罩,对照组呼吸空气,实验组呼吸医用纯氧60 min。应用条件-测试刺激,记录吸氧前(pre0)、吸氧20 min(Oxy20)、吸氧50 min(Oxy50)、吸氧后30 min(post30)的脑电图,计算听觉P50潜伏期和P50感觉门控电位(S1与S2振幅之差)。结果 S1刺激在4个时间点各组P50潜伏期相对稳定(P0.7);吸氧50 min时,实验组比对照组P50潜伏期缩短(P0.05)。S2刺激在4个时间点各组P50潜伏期相对稳定(P0.30),两组间比较无显著性差异(P0.05)。对照组P50门控电位比较稳定(P=0.70),而实验组随吸氧时间逐渐延长,电位越来越高,停止吸氧后,电位迅速回落,Oxy20和post30(P=0.04)、Oxy50和post30(P=0.02)相比均有显著性差异。组间比较,4个时间点均无显著性差异(P0.05)。结论健康人吸60 min纯氧,可能缩短对刺激的反应时间,有增强听觉门控电位的趋势。  相似文献   
105.
Hypereutectic Al-Si alloys are attractive materials in the fields of electronic packaging and aerospace. A Bi2O3-ZnO-B2O3 system lead-free brazing filler glass was employed to braze hypereutectic Al-50Si alloys in air. The hypereutectic Al-50Si alloys were pre-oxidized and the low-temperature glass powder was flake-shaped in the brazing process. The effects of brazing temperature and time on joints microstructure evolution, resulting mechanical strength, and air tightness were systematically investigated. The results indicated that the maximum shear strength of the joint was 34.49 MPa and leakage rate was 1.0 × 10−10 Pa m3/s at a temperature of 495 °C for 30 min. Crystalline phases, including Bi24B2O39 and Bi2O3, were generated in the glass joint. The formation of a diffusion transition layer with a thickness of 3 μm, including elements of Al, Si, Zn, Bi, Na, and B, was the key to form an effective joint. The elements of Al, Si, and Bi had a short diffusion distance while the elements of Zn, Na, and B diffused in a long way under brazing condition.  相似文献   
106.
目的 研究振幅整合脑电图联合感觉门控电位P50 对重症脑血管病患者预后结局的评估价值。 方法 选取2017 年5 月—2019 年5 月郴州市第一人民医院诊治的重症脑血管病患者62 例。根据患者预后情 况将其分成病死组(14 例)和预后良好组(48 例),比较两组患者振幅整合脑电图、P50 结果;分析振幅整 合脑电图、P50 与格拉斯哥预后评分表(GOS)评分的相关性;评估振幅整合脑电图、P50 单独与联合检测 对患者的预后价值。结果 两组振幅整合脑电图分级比较,差异有统计学意义(P <0.05)。病死组P50 较预 后良好组高(P <0.05)。预后良好组GOS 评分较病死组高(P <0.05)。振幅整合脑电图、P50 与GOS 评分呈 负相关(r s =-0.629 和-0.703,均P <0.05)。联合检测对患者预后的价值高于振幅整合脑电图、P50单独检测 (P <0.05)。结论 P50 联合振幅整合脑电图检测对重症脑血管病患者具有较高的预后评估价值。  相似文献   
107.
目的 探讨特发性良性阵发性位置性眩晕(benign paroxysmal positional vertigo,BPPV)成功复位后出现残余头晕的患者感觉门控P50特点。方法 选择2018年6月至2019年11月就诊于大连市第三人民医院符合入组条件的确诊为BPPV并成功行手法复位后的患者60例,根据治疗7天后有无残余头晕(residual dizziness,RD)分为RD组和无RD组,行感觉门控电位P50检测,记录S1-P50及S2-P50的潜伏期、波幅及S2-P50/S1-P50波幅比值,进行统计学分析。结果 与无RD组相比,RD组S1-P50波幅减低,潜伏期延长,S2-P50波幅增高,潜伏期延长(P<0.05);RD组S2/S1比值高于无RD组,差异具有统计学意义(P<0.05)。结论 感觉门控P50可以客观评价BPPV成功复位后残余头晕患者感觉门控功能缺损情况,提示患者可能存在情绪障碍,为临床治疗提供方向。  相似文献   
108.
This article describes a digital technique that combines intraoral digital scans with a 3-dimensional facial scan to predict the outcome of prosthodontic treatment of anterior teeth at the treatment planning phase. This approach may increase patient acceptance of the definitive treatment, as the altered facial appearance is visualized with definitive prosthodontic restorations, thereby improving communication before treatment begins.  相似文献   
109.
This article describes a workflow based on a top-down approach to provide a fixed-type immediate interim restoration after placing a single implant using a digitally driven surgical guide and a matrix-positioning device. A characteristic of the technique is that both the surgical guide and the matrix-positioning device are fabricated from a single diagnostic virtual trial restoration designed on computer-aided design (CAD) software. This workflow may shorten the time required for chairside placement of an interim restoration and enhance esthetics when rehabilitating anterior teeth.  相似文献   
110.

Introduction

Intracerebral hemorrhage (ICH) is a major clinical concern with anticoagulation therapy. The effect of a new oral direct FXa inhibitor, edoxaban, was determined in a rat model of ICH and compared with a direct thrombin inhibitor, melagatran, and heparin.

Methods

To induce ICH, 0.1 U collagenase type VII was injected into the striatum of male Wistar rats under anesthesia with thiopental or halothane. Immediately after ICH induction, edoxaban, melagatran, or heparin were infused intravenously. Five hours after ICH induction, the brain was removed and ICH size was measured. To estimate the margin of safety, antithrombotic effects were evaluated in a rat venous thrombosis model.

Results

Edoxaban at 6 mg/kg/h significantly increased ICH volume (1.8-fold) and prolonged prothrombin time (PT) 2.8-fold compared to the vehicle group. No deaths were observed with edoxaban. Melagatran at 1 mg/kg/h increased ICH volume at 1 mg/kg/h (2.8-fold) with 6.1-fold PT prolongation. At 3 mg/kg/h, all rats died due to severe ICH (3.9-fold). Heparin at both 100 and 500 U/kg/h significantly increased ICH. At 500 U/kg/h, 5 out of 8 rats died. The doses required for 50% inhibition of thrombosis of edoxaban, melagatran, and heparin were 0.045 mg/kg/h, 0.14 mg/kg/h, and 55 U/kg/h, respectively. The safety margins between antithrombotic and ICH exacerbation effects of these anticoagulants were 133, 7.1, and 1.8, respectively.

Conclusion

The safety margin of edoxaban was wider than that of melagatran or heparin. These results suggest that edoxaban may be preferable from the perspective of ICH exacerbation risk.  相似文献   
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