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101.
Mechanical ventilation (MV) during exacerbation of asthma or chronic obstructive pulmonary disease (COPD) is unequivocally needed when apnoea, cardiorespiratory arrest, coma, hypoxia or treatment failure is present. The need is less clear when the patient can respond, has intact airway reflexes and spontaneous respiration. In this situation, acidosis is an important factor in the decision to institute MV. This study aimed to provide a clinical means of identifying patients with acute respiratory acidosis (ARA) in a setting where blood gas analysis is unavailable. We undertook a prospective, observational study of consecutive patients who presented to two emergency departments with severe and life-threatening exacerbation of asthma or COPD. Each underwent clinical assessment, treatment and blood gas analysis. The outcome measure was ARA or mixed ARA and metabolic acidosis. A total of 127 episodes in patients aged 15-90 years (65.3% males and 34.7% females) were included in the study. Of these, 62.2% had asthma and 37.8% had COPD; 71.7% had life-threatening and 28.3% had severe attacks. Overall, the adjusted odds ratio (and 95% confidence intervals) for predictors of ARA were 7.09 (1.79-28.06) for drowsiness, 4.11 (1.31-12.88) for flushing, 3.34 (1.01-11.02) for having COPD and 2.86 (1.01-8.07) for intercostal retractions. In conclusion, with drowsiness, the likelihood of ARA is about seven times higher. The presence of flushing, COPD and intercostal retractions also increase the risk of ARA. 相似文献
102.
目的:建立嵌体修复后牙体三维有限元模型,应用不同的龈壁设计,观察相关力学参数变化。方法:①下颌第一磨牙标本来源于佳木斯大学解剖学教研室,标本要求:磨耗少,其牙冠长、宽、高接近正常下颌第一磨牙的均值。②建立有限元模型:用蜡块将牙齿固定,使扫描尽可能与牙体长轴垂直,扫描至牙颈部。根据各层图上建立的平面坐标,设颊舌向为X轴,近远中向为Y轴,龈向为Z轴。按照有限元单元划分的原则和计算机分析软件的要求,对各个断层的解剖轮廓进行边界节点选择和单元网格划分。根据组织结构特点,进行节点调整。通过人机交互,输入每个节点的坐标和组成单元的节点,分层建立由六面体单元所构成的三维有限元模型。③计算:在后牙邻洞应用不同的龈壁设计,于面上施加一竖直向下的力,大小为170N,方向与Z轴相同,通过有限元分析计算获取应力分布图像和应力数据。结果:①龈壁高度的增加,使牙釉质应力减少(0.1~0.27MPa),对牙本质无明显影响。②龈壁宽度的增加,使牙釉质应力增加(0.1~0.27MPa)、牙本质应力亦增加(0.01~0.03MPa)。③龈壁角度的增加,牙釉质和牙本质应力无明显改变。结论:Ⅱ类洞嵌体设计时,龈壁高度增加,宽度尽量减小有利于减小修复后牙体的应力。龈壁角度的有无对牙体应力无影响。 相似文献
103.
Background/Purpose
The purpose of this study was to review the management of obstructive symptoms and enterocolitis (HAEC) following pull-through for Hirschsprung's disease.Methods
A systematic review and meta-analysis (1992–2017) was performed. Included studies were: randomized controlled trials (RCT), retrospective/prospective case–control (C-C), case-series (C-S). Random-effect model was used to produce risk ratio (RR) [95% CI]. P?<?0.05 was considered significant.Results
Twenty-nine studies were identified. Routine postoperative dilatations (5 C-S, 2 C-C; 405 patients): no effect on stricture incidence (RR 0.3 [0.02–5.7]; p?=?0.4). Routine postoperative rectal irrigations (2 C-C; 172 patients): reduced HAEC incidence (RR 0.2 [0.1–0.5]; p?=?0.001). Posterior myotomy/myectomy (4 C-S; 53 patients): resolved obstructive symptoms in 79% [60.6–93.5] and HAEC in 80% [64.1–92.1]. Botulinum toxin injection (9 C-S; 166 patients): short-term response in 77.3% [68.2–85.2], long-term response in 43.0% [26.9–59.9]. Topical nitric oxide (3 C-S; 13 patients): improvement in 100% of patients. Probiotic prophylaxis (3 RCT; 160 patients): no reduction in HAEC (RR 0.6 [0.2–1.7]; p?=?0.3). Anti-inflammatory drugs (1 C-S, sodium cromoglycate; 8 patients): improvement of HAEC in 75% of patients.Conclusions
Several strategies with variable results are available in patients with obstructive symptoms and HAEC. Routine postoperative dilatations and prophylactic probiotics have no role in reducing the incidence of postoperative obstructive symptoms and HAEC.Type of study
Systematic review and meta-analysis.Level of evidence
Level II. 相似文献104.
Measurements of spontaneous ultraweak photon emission and delayed luminescence from human cancer tissues 总被引:1,自引:0,他引:1
Kim J Choi C Lim J You H Sim SB Yom YK Kim EH Soh KS 《Journal of alternative and complementary medicine (New York, N.Y.)》2005,11(5):879-884
OBJECTIVE: The aim of this study was to measure spontaneous photon emission (SPE) and delayed luminescence (DL) from various human cancer tissues. MATERIALS AND METHODS: A photomultiplier tube attached to a dark chamber was used for the detection of ultraweak photon emission from cancer tissues in the chamber. The samples were illuminated with a 150 W metal halide lamp for the measurement of delayed luminescence. Frozen tissues were provided by the hospitals and preserved in saline solution in a CO2 incubator for 1 hour before starting the measurement of spontaneous photon emission. We successively measured the afterglows from the samples after 30-second irradiation of the lamp. The samples were divided into two groups: tumor tissues and normal tissues around tumor tissues. We presented experimental data and interpreted their characteristic patterns of spontaneous photon emission and delayed luminescence. RESULTS: Mean values of spontaneous photon emissions from the normal tissues and the tumor tissues were measured with the standard errors of the mean as 625 +/- 419 counts/minute/cm2 (n = 6) and 982 +/- 513 counts/minute/cm2 (n = 14), respectively. Peak values of the intensity of delayed luminescence from normal and cancerous tissues were 63 +/- 20 counts/ms (n = 6) and 48 +/- 12 counts/ms (n = 14). CONCLUSIONS: The intensity of spontaneous photon emissions from cancer tissues were mostly discriminated from those of normal tissues, and their delayed luminescent properties were investigated. 相似文献
105.
血管内皮生长因子与白细胞介素12在急性白血病不同时期血清中的变化 总被引:1,自引:0,他引:1
目的:由于造血干/祖细胞发生基因突变,子代细胞增殖失控等导致的恶性血液病。血管内皮生长因子和白细胞介素12参与这一发生发展过程,检测不同时期其在急性白血病患者静脉血中的水平,有利于认知与血管新生及体液免疫的相关性。方法:随机选择2005-06/2006-04在吉林市中心医院住院的急性白血病患者25例,均经FAB分型或免疫学分型确诊,患者知情同意,并经医院伦理委员会批准。将患者分为:①初诊未治组10例。②复发组5例。③完全缓解组10例。并设9名健康查体者为正常对照。应用定量酶联免疫吸附实验测定受试者血清中血管内皮生长因子和白细胞介素12的水平,在评定白细胞介素12水平时,将初诊未治组与复发组合并为初诊复发组:①两组的发病机制相似。②两组病例数较少,单独观察没有统计学意义。结果:25例患者和9名健康对照者均进入结果分析。①初诊未治组血管内皮生长因子含量高于完全缓解组及正常对照组(P均<0.05)。②正常对照组白细胞介素12水平与初诊复发组、完全缓解组之间差异均具有显著性意义(P均<0.05)。③正常对照组血管内皮生长因子含量与白细胞介素12之间存在负相关(r=-0.9644P<0.05)。④初诊复发组、完全缓解组血管内皮生长因子和白细胞介素12含量之间均无相关性(r=-0.0883,-0.3593,P均>0.05)。结论:急性白血病患者血清中血管内皮生长因子和白细胞介素12含量与临床病情变化有关,可以作为诊断和预测急性白血病发生和复发的指标。 相似文献
106.
Piacibello W; Lu L; Williams D; Aglietta M; Rubin BY; Cooper S; Wachter M; Gavosto F; Broxmeyer HE 《Blood》1986,68(6):1339-1347
Human gamma interferon (HuIFN gamma) was evaluated for its effects on the release from human peripheral blood T lymphocytes (greater than 98% pure) stimulated by phytohemagglutinin (PHA) of activities that can stimulate granulocyte-macrophage (CFU-GM) colonies and clusters, erythroid (BFU-E) bursts, and mixed (CFU-GEMM) colonies. T lymphocytes did not release these activities in the absence of PHA with or without HuIFN gamma. In the presence of PHA, pure natural HuIFN gamma at concentrations of 0.1 to 100 U/mL significantly enhanced release of these colony-stimulating activities. Although enhanced release of granulocyte-macrophage colony-stimulating activities were noted when T lymphocytes were added to the conditioning medium in the presence of 0.1%, 0.5%, and 1% PHA, enhanced release of burst-promoting and mixed colony activities was seen only in the presence of 0.1% and 0.5% PHA. The enhanced release of colony-stimulating activities was not due to HuIFN gamma-suppression of the release from PHA-stimulated T lymphocytes of suppressor molecules. The enhancing effects of natural HuIFN gamma were neutralized with a monoclonal anti-natural HuIFN gamma, and recombinant HuIFN gamma mimicked the enhancing effects of the natural HuIFN gamma. This enhancing effect was noted only when HuIFN gamma was added with the T lymphocytes and PHA during the first 24 hours of incubation. T lymphocytes were separated into T4+, T8-, T8+, and T4- subsets (greater than 98% pure for the appropriate phenotypes) after incubation with OKT4- and OKT8- monoclonal antibodies and sorting on a fluorescence-activated cell sorter (FACS). All types of colony-stimulating activities were released from each population after stimulation with PHA, but enhanced release of these activities in the presence of HuIFN gamma was only detected with the T4+ or T8- subsets of lymphocytes. It cannot be concluded from these studies whether HuIFN gamma is enhancing the release of one or several types of colony-stimulating activities, but these studies suggest a role for HuIFN gamma and T4+ lymphocyte subsets in the regulation in vitro of the release of colony-stimulating activities. 相似文献
107.
Akihiro Kawauchi Kazumi Kamoi Jintetsu Soh Yasuyuki Naitoh Koji Okihara Tsuneharu Miki 《International journal of urology》2010,17(3):289-292
The objective of this paper is to report our initial experience in laparoendoscopic single‐site surgery (LESS). One patient underwent LESS varicocelectomy and another patient underwent LESS pyeloplasty. The Triport was inserted into the abdomen through the umbilical incision. In the varicocelectomy, testicular vessels were coagulated by a vessel‐sealing system, and transected. In the pyeloplasty, a 2‐mm needlescopic port was added to facilitate the procedure, and a dismembered procedure was performed. Total operative duration was 60 min for the varicocelectomy and 240 min for the pyeloplasty. Blood loss was minimal and no perioperative complications occurred. At the 3‐month follow up, no postoperative complications were observed and there was no complaint of pain. LESS varicocelectomy and pyeloplasty were successfully performed with excellent cosmetic results and no complications. 相似文献
108.
Jandee Lee Kuk Young Nah Ra Mi Kim Yeun Hee Ahn Euy-Young Soh Woong Youn Chung 《Surgical endoscopy》2010,24(12):3186-3194
Background
Robotic thyroidectomy using a gasless transaxillary approach, first described in 2008, has become popular. This study compared outcomes, including postoperative distress and patient satisfaction, for patients undergoing robotic thyroidectomy with those for patients treated by conventional open thyroidectomy. 相似文献109.
Fly ash from industrial waste incinerators has been a significant concern because of their constituent toxic heavy metals and organic compounds. The objective of this study was to identify the subacute inhalation toxicity of fly ash from industrial waste incinerators, using whole body inhalation exposure chambers. Male and female groups of Sprague-Dawley rats were exposed to fly ash by inhalation of concentrations of 0, 50, 100, 200?mg/m(3), for 6?h/day, 5 days/week for 4 weeks. There was no significant difference in body weight, and relative organ weight to body weight, between the exposure groups and the control group. Hematological examinations revealed a significant increase of monocyte counts in fly ash exposed rats and brown pigment laden macrophage was found in the lungs of rats exposed to high concentration of fly ash. A decrease of blood glucose levels and an increase in glutamate oxaloacetate transaminase activity were observed in fly ash treated rats. There was also a significant increase of lactate dehydrogenase levels in rat blood exposed fly ash. A significant dose-dependent increase of DNA damage was found in lymphocytes, spleen, bronchoalveolar lavage, liver, lung, and thymus of rats exposed to fly ash. In addition, the level of lipid peroxidation was increased in the plasma of rats exposed to a high concentration of fly ash. These results suggest that inhalation of fly ash from industrial waste incinerators can induce histopathologic, hematological, and serum biochemical changes and oxidative damage. 相似文献
110.
Mizoguchi H Komatsu T Iwata Y Watanabe C Watanabe H Orito T Katsuyama S Yonezawa A Onodera K Sakurada T Sakurada S 《Neuroscience letters》2011,504(2):83-87
Rapid balance reactions such as compensatory reach to grasp represent important response strategies following unexpected loss of balance. While it has been assumed that early corrective actions arise from subcortical networks, recent research has prompted speculation about the potential role of cortical involvement. With reach to grasp reactions there is evidence of parallels in the control of perturbation-evoked reaching versus rapid voluntary reaching. However, the potential role of cortical involvement in such rapid balance reactions remains speculative. To test if cortical motor regions are involved we used continuous theta burst stimulation (cTBS) to temporarily suppress the hand area of primary motor cortex (M1) in participants involved in two reaching conditions: (1) rapid compensatory perturbation-evoked reach to grasp and (2) voluntary reach to grasp in response to an auditory cue. We hypothesized that following cTBS to the left M1 hand area we would find diminished EMG responses in the reaching (right) hand for both compensatory and voluntary movements. To isolate balance reactions to the upper limb participants were seated in an elevated tilt-chair with a stable handle positioned in front of their right shoulder. The chair was held vertical by a magnet and triggered to fall backward randomly. To regain balance, participants were instructed to reach for the handle as quickly as possible with the right hand upon chair release. Intermixed with perturbation trials, participants were also required to reach for the same handle but in response to an auditory tone. Muscle activity was recorded from several muscles of the right arm/hand using electromyography. As expected, movement time and muscle onsets were much faster following perturbation versus auditory-cued reaching. The novel finding from our study was the reduced amplitude of hand muscle activity post-cTBS for both perturbation-cued and auditory-cued reaches. Moreover, this reduction was specific to the cTBS-targeted hand with no effect on remaining arm muscles. These findings support the idea that cortical networks contribute to both volitional and perturbation-evoked reaches and provide evidence for M1involvement in driving early arm responses toward a target following sudden loss of balance. 相似文献