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81.
一种具有高信噪比的脉搏波光电传感器的研制 总被引:5,自引:0,他引:5
目的:探讨研制一种生理信号光电传感器。方法:利用光电传感器检测通过指端毛细血管后的光强度的变化,将光信号转换成电信号,再经过电信号1/V转换、放大、滤波处理。结果:获得了清晰稳定的指端容积脉搏波。结论:高信噪比的光电传感器可用作于临床监测和生理信号分析处理系统。 相似文献
82.
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
83.
Akitoshi Yamada Yoshitaka Takeda Satoru Hayashi Kazuta Shimizu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(9):456-458
We experienced a case of familial spontaneous pneumothorax in three generations. Six of 13 family members had episodes of
spontaneous pneumothorax. It is well established that there are some diseases associated with human leukocyte antigen (HLA).
We performed HLA phenotyping for HLA of A, B and C. In our study, we detected the HLA haplotype A2, B61 in three of 4 who
had episodes of spontaneous pneumothorax. The HLA haplotype A2, B70 were also detected in three of 4 who had episodes. This
suggests that familial spontaneous pneumothorax might have hereditary factors. 相似文献
84.
目的总结26例肾下型腹主动脉瘤的手术治疗经验。方法回顾性分析近5年多来手术治疗26例肾下型腹主动脉瘤的临床资料,全组26例,术前均经影像检查证实诊断。行择期手术21例,破裂型腹主动脉瘤急诊手术5例。26例均行腹主动脉瘤切除,人工血管重建术。结果围手术期死亡2例,均为急症手术患者,总病死率7.7%,急诊手术病死率40.0%。随访时间1-5年。术后1,3,5年生存率分别为96%,88%,75%。死亡原因均与腹主动脉瘤和手术无关。结论CTA检查是诊断腹主动脉瘤的可靠方法。手术治疗仍是治疗腹主动脉瘤的重要方法。瘤体直径不是决定手术的唯一指征。影响手术的危险因素主要是高龄、严重的心肺疾病和肾功能不全。 相似文献
85.
T.-N. Wu Chen-Yang Shen Saou-Hsing Liou Guang-Yang Yang K.-N. Ko Show-Lin Chao Chao-Chun Hsu P.-Y. Chang 《International archives of occupational and environmental health》1997,69(6):386-391
To monitor the lead hazards in industries and to investigate the prevalence of elevated blood lead levels (BLLs) in lead-exposed
workers, a lead surveillance system (PRESS-BLLs) has been established and operated in Taiwan, Republic of China, since July
1993. A cohort of lead-exposed workers who received a periodic annual health examination at 55 accredited hospital laboratories
was constructed. A total of 9807 separate BLL measurements were reported to the system in 1994. The mean BLL was 15.8 μg/dl
in male workers and 11.6 μg/dl in female workers. The mean BLL of lead-exposed workers was significantly (P<0.05, z-test) higher than that of the general Taiwanese population (8.6 μg/dl for males and 6.7 μg/dl for females). In addition,
the BLLs of 983 (10.0%) workers exceeded the regulatory action level (40 μg/dl for males; 30 μg/dl for females). The workplaces
and homes of 57% of the workers with elevated BLLs were thoroughly investigated to determine the sources of lead contamination.
These actions identified the causes of elevated BLLs and set up strategies to reduce workers’ lead exposure. The establishment
of this occupational lead surveillance system represents a method for monitoring of lead hazards from occupational and environmental
settings to prevent lead poisoning. The information acquired from the system can help in the setting up of a priority of prevention
and the development of control measures. It is also useful for further monitoring of changes in the BLLs of the lead-exposed-worker
cohort. The Health Department of Taiwan can use this information to evaluate the effectiveness of current industrial hygiene
practice. Subjects with elevated BLLs have been medically treated and placed on long-term follow-up for sequelae.
Received: 2 September 1996/Accepted: 29 November 1996 相似文献
86.
87.
检测45例正常人和44例不同病期白血病血浆和外周血白细胞内维生素A、E、C、B12和β-胡罗卜素、叶酸浓度。结果表明,初治白血病患者血浆维生素A、β-胡罗卜素降低(P<0.01),未缓期解者血浆β-胡罗卜素和叶酸低于正常(P<0.01和P<0.05)。在初治和未缓解期患者的外周血白细胞内,维生素E、C、B12和β-胡罗卜素均显著降低(P<0.01~0.001)。而且,外周血白细胞内维生素代谢异常比血浆更为显著。提示维生素含量变化对于解释病因,预测疗效及估计预后有一定的价值。 相似文献
88.
对豚鼠胃肠道各段的研究发现,在胃体、胃底和幽门的粘膜下层内,血管仅由神经纤维束伴行。除小肠粘膜下层可见神经节丛与血管伴行外,在盲肠粘膜下层,亦可见神经节丛与小动、静脉伴行,尤以血管始段及第一分支段最明显。某些神经节丛还发出神经纤维束投射到血管壁上。在结肠和直肠均未见到神经节丛与血管的伴行现象。 相似文献
89.
Abstract: The effects of pyridoxalated hemoglobin polyoxyethylene conjugate (PHP) and stroma-free hemoglobin (SFH) on vascular responsiveness to various vasoactive substances were examined in isolated perfused rat kidneys. The kidneys isolated from rats were perfused with 6% PHP, 6% SFH, and 6% hydroxyethylstarch (HES) solution at a constant flow rate. Vascular responsiveness to acetylcholine (ACh), nitroglycerin (NG), norepinephrine (NE), and angiotensin-II (ANG-II) was examined by measuring the perfusion pressure (PP). Effects of inhibition of endothelium-derived relaxing factor (EDRF) by NG -monomethyl L-arginine (L-NMMA) on NE-induced and ANG-II-induced renal vascular responses were examined. ACh and NG induced a dose-dependent decrease in perfusion pressure (PP) in all groups. NE and ANG-II induced an increase in PP in all groups, but NE-induced and ANG-II-induced responses in the PHP-perfused and SFH-perfused groups were significantly larger than those in the HES-perfused group. L-NMMA did not alter vascular responsiveness to NE and ANG-II. These results indicate that PHP and SFH do not inhibit EDRF induced by ACh, but hemoglobin moiety per se does augment the vascular responsiveness to NE and ANG-II in the isolated perfused rat kidney. 相似文献
90.
体外静脉—静脉转流下原位肝移植围术期酸碱,生化的变化 总被引:9,自引:2,他引:7
目的:观察体外静脉转流下原位肝移植围术期酸碱和生化的变化。方法:7例病人行原位肝移植术,在无肝期行体外静脉-静脉转流,监测围术期酸碱和生化指标。结果:(1)与术前相比,pH各期有所下降,但仍维持在正常范围,BE和SBC在转流60分钟及关腹时降低;与转流前期相比。pH以后各期变化不大。术期pH在7.35~7.45范围之内;(2)血糖在各期都升高,血钙降低,体温逐渐降低;(3)血钾在肝血管开放后一过性增高,由3.17mmol/L升至3.53mmol/L。结论;体外静脉转流下原位肝移植术,术中酸碱和生化变化轻微,避免了明显的代谢性酸中毒和高血钾,但体温和血糖变化明显。 相似文献