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51.
52.
对某镍业公司车间空气中镍浓度和工人指甲镍含量进行了测定。按照生产过程和卫生学特点,将所获数据划分为碎矿压球、电炉转炉和汽车维修三组。空气镍浓度几何均值分别为0.0978、0.0623和0.0202mg/m~3;工人指甲镍几何均值分别为23.04、21.07和4.84μg/g;两者呈现一定的接触水平-反应关系。表明以指甲镍作为职业性接镍人群的生物监测指标有一定的参考价值。  相似文献   
53.
目的 探讨近端/远端复合肌肉动作电位振幅比率在术后面神经肿瘤侵犯段功能评估上的价值和对早期面神经修复的指导意义。方法 比较术末面神经近端/远端复合肌肉动作电位振幅比率和术后2周、6个月患侧面神经功能的H-B分级之间的关系。结果 术后6个月面神经H-B分级恢复到Ⅰ-Ⅱ级者,术末近端/远端复合肌肉动作电位振幅比率均>0.3。结论 术末面神经近端/远端复合肌肉动作电位振幅比率是判断术后面神经远期功能,特别是肿瘤侵犯段功能的重要指标,为术中直接修复面神经提供了指导依据。  相似文献   
54.
术中电生理检测在肘管综合征的应用   总被引:1,自引:0,他引:1  
目的 :探讨术中电生理监测在肘管综合征手术中的临床应用价值。方法 :对25例肘管综合征手术患者进行尺神经松解前后的电生理术中监测。结果 :术中尺神经肘管松解前后 ,传导速度提高50% ,潜伏期缩短30%,其中传导速度的改善有显著意义(P<0.05)。结论 :传导速度是较敏感的术中监测参数。肘管综合征术中应用电生理检测有一定临床意义。  相似文献   
55.
Objective To evaluate low-dose CT coronary angiography with prospective electrocardiogram (ECG)-triggering using dual-source CT scanner.Methods Sixty-eight patients who underwent coronary CT angiography using a dual-source CT scanner were divided into 2 groups: group A (38 cases) and group B (30 cases).Prospective ECG-triggering sequence scan mode was employed for group A.Inclusion criteria included: heart rate <70 bpm, sinus rhythm, and heart rate fluctuation less than 10 bpm.Data acquisition was set at 70% of the RR-interval.Retrospective ECG-gating helical scan was performed for group B.Inclusion criteria included heart rates < 70 bpm and sinus rhythm.The exclusion criteria included heart failure and serious arrhythmias.In both groups, patients with a BMI≥24 kg/m2 were examined with a tube voltage of 120 kV, whereas patients with a BMI <24 kg/m2 were examined with a tube voltage of 100 kV.All images were transferred to a workstation for further processing and analysis.The imaging quality was evaluated.The imaging quality of coronary artery segments were compared with rank sum test between the two groups, and the radiation dose were compared with t test.Results A total of 476 coronary artery segments were evaluated in group A and 372 segments were evaluated in group B.The mean score of imaging quality for coronary artery segments in group A was 3.48±0.59 and that in group B was 3.53±0.58.There was no statistical difference in imaging quality between the two groups (Z=-1.432, P=0.187).The effective dose was on average (2.51±0.54) mSv (range 1.3--3.3 mSv) in group A, whereas on average (14.55±3.54) rosy (range 7.1--20.2 mSv) in group B.There was a statistical difference between the two groups (t=18.484, P=0.000).Conclusions Low-dose prospective ECG-triggering sequence scan in dual-source CT coronary angiography is feasible in patients with low heart rate and regular cardiac rhythm.This scan mode can substantially reduce radiation doses while preserving good diagnostic image quality.  相似文献   
56.
目的 探讨对急性重型脑损伤患者行脑组织氧代谢监测的临床意义。 方法对2 8例急性重型脑损伤患者 (均在全麻下急诊行血肿清除术和 (或 )去骨瓣减压术 )术中及术后持续进行脑组织氧代谢监测 ,观察脑组织氧分压 (PbtO2 )、二氧化碳分压 (PbtCO2 )和pH值 (pHbt)的变化。 结果  (1) 2 8例脑外伤患者在剪开硬脑膜后PbtO2 、pHbt分别从 (13± 4 )mmHg、(6 .96± 0 .15 )增加至 (2 1± 5 )mmHg、7.0 5± 0 .12 (P <0 .0 5 ) ,PbtCO2 从 (6 1± 6 )mmHg下降至 (5 3± 5 )mmHg(P <0 .0 5 )。(2 )其中 2 4例脑外伤患者在血肿清除后 ,PbtO2 、pHbt值分别从 (2 1± 4 )mmHg、7.0 5± 0 .11增加至 (2 8± 6 )mmHg、7.15± 0 .10 (P <0 .0 5 ) ,PbtCO2 从 (5 2± 6 )mmHg下降至 (4 5± 4 )mmHg(P <0 .0 5 )。 (3)PbtO2 <10mmHg持续 30min以上的患者预后差。 结论  (1)脑组织氧代谢监测是一种安全、可靠的监测手段 ,能直接动态反映脑组织的病理生理变化 ,及时发现脑组织缺血缺氧 ,以指导治疗。 (2 )持续进行脑组织氧代谢监测可判断重型脑外伤患者的预后。  相似文献   
57.
Up to 30% of patients with temporal lobe epilepsy (TLE) remain without remarkable changes in MRI. In this study we investigated the role of (1)H-MR spectroscopy ((1)H-MRS) in lateralizing the affected hemisphere in the mentioned patient group. Twenty-two consecutive patients diagnosed with TLE were investigated by high resolution MRI and (1)H-MRS. We examined the incidence and diagnostic accuracy of temporal metabolite alterations determined by Linear Combination of Model Spectra (L C Model) via water reference. Metabolite values of each hemisphere of TLE patients were compared with healthy controls. Results of metabolite alterations were related to intensive video EEG focus localization. Reduction of N-acetylaspartate + N-acetylaspartyl-glutamate (tNAA) in the affected hemisphere revealed identification in six of nine patients (66%) with unilateral TLE. Group comparison revealed a significant reduction of tNAA (6.1+/-0.8*) in the involved temporal lobe compared with controls (6.67+/-0.4*, P=0.026). Choline levels were significantly increased in the affected hemisphere (1.42+/-0.17*) compared with healthy controls (1.22+/-0.17*, P=0.035). The results of our study show that (1)H-MRS is able to identify the affected hemisphere of MRI negative TLE patients and can be used as an additive tool in multimodal focus localization.  相似文献   
58.
The intubating conditions and neuromuscular blocking profile following 600 micrograms.kg-1 rocuronium (Org 9426) have been investigated in patients under various experimental conditions. They were compared with conditions following 1.5 mg.kg-1 suxamethonium, preceded by a precurarising dose (10 mg) of gallamine, and with those in a control group in the absence of a muscle relaxant. Rocuronium produced good to excellent intubating conditions at 60 as well as at 90 s after administration, even though there was only a partial blockade of the adductor pollicis muscle. Intubating conditions following suxamethonium were comparable with those after rocuronium. Half of the control patients could be intubated. The clinical duration and the recovery time of 600 micrograms.kg-1 of rocuronium were 24(4) and 9(3) min (mean(s.d.)), respectively. Rocuronium may have a major advantage over existing non-depolarising muscle relaxants due to the early presence of excellent intubating conditions. The results indicate that rocuronium may replace suxamethonium in procedures in which rapid sequence induction is required.  相似文献   
59.
Summary: Purpose : We wished to compare outcome 5 years after temporal lobectomy in 28 patients selected for surgery on the basis of interictal EEG patterns with that in 46 patients who underwent EEG-video monitoring studies as part of their preoperative evaluation during the same era.
Methods : The 28 nonmonitored patients had interictal EEG patterns that demonstrated a consistent, unilateral, anterior-midtemporal epileptiform focus, without discordant findings from other studies. Outcomes were assessed for years 4 and 5 after operation.
Results : Twenty-six of 28 (92.9%) nonmonitored patients were seizure-free or had at least 75% reduction in seizures. Twenty-nine of 46 (63.0%) monitored patients were seizure-free or had at least 75% reduction in seizures. Preoperative interictal EEGs of 29 of these patients showed independently localized bitemporal, ex-tratemporal, midposterior temporal, or diffuse epileptiform patterns. The remaining 17 monitored patients had preoperative strictly unilateral anterior-midtemporal interictal discharges, and their outcome was comparable to the nonmonitored group, with 15 (88.8%) seizure-free or with at least 75% reduction in seizures.
Conclusions : A proportion of candidates for epilepsy surgery can be selected without ictal recordings provided that interictal EEGs demonstrate consistent unilateral anterior-midtemporal epileptiform discharges and that other data are not discordant.  相似文献   
60.
 Dermal exposures of methanol were administered in a clinical study designed to compare several biological indicators. Four subjects were exposed in five exposure sessions of varying length. In each session, a sequence of measurements of methanol concentrations in blood, breath, and headspace samples of air at exposed and unexposed skin were collected before and after dermal exposures. Skin headspace samples, collected in gas sampling bags, were designed to reflect equilibrium skin: air partitioning. At exposed skin, headspace samples were highly elevated for at least 8 h following exposure, indicating the presence of a methanol reservoir in skin. After exposure, methanol concentrations at exposed skin showed a rapid initial decline, then a slower first-order decrease. Methanol concentrations were clearly detectable in headspace samples at unexposed skin. Substantial transfer from exposed skin occurred due to mechanical contact and washing. When transfer was restricted, surface concentrations at unexposed skin were similar to levels in breath and were strongly correlated to methanol concentrations in blood. While results are preliminary due to the small sample sizes and several unresolved experimental issues, the simple, rapid, and noninvasive skin headspace measurements appear useful as a biological exposure indicator that clearly shows the presence and site of a dermal exposure, and measurements at unexposed skin reflect concentrations in blood. Received: 14 March 1995/Accepted: 3 November 1995  相似文献   
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