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目的 检测并比较心肌梗死急性期不同时间点,β2自身抗体阳性组与阴性组,患者血清中Fas/APO-1水平差异,了解β2自身抗体对Fas/APO-1的影响。方法 41例急性心肌梗死患者,分别于发病24h、7天、2~4周时取血,采用ELISA的方法,检测血清中β2自身抗体的阳性率以及Fas/APO-1的水平;另外取34位性别、年龄匹配的健康人的血同法检测Fas/APO-1作为对照。结果心肌梗死急性期Fas/APO-1的水平均高于对照组(P〈0.05),以梗死后24hFas/APO-1的水平为最高;心肌梗死急性期不同时间点,β2自身抗体阳性组Fas/APO-1的水平均高于阴性组,但两组的结果差异无显著性(P〉0.05)。结论 血清Fas/APO-1水平可以在一定程度上反映心肌细胞凋亡的变化趋势,β2自身抗体对Fas/APO-1的确切影响,有待更大规模的实验来证实。 相似文献
14.
Zongli Lin Meir Pachter Siva Banda Yacov Shamash 《Optimal control applications & methods.》2002,23(1):21-43
A design technique (Control of Uncertain Systems with Bounded Inputs, Tarbouriech S, Garcia G, (Eds), Lecture Notes in Control and Information Sciences, vol. 227 , Springer: Berlin, 1997; 173–186) recently proposed for stabilization of a linear system with rate‐limited actuators is utilized to design feedback laws that cause the system output to track a desired command signal. This design technique combines two design techniques recently developed for linear systems with position limited actuators, piecewise‐linear LQ control (Automatica, 1994; 30 : 403–416) and low‐and‐high gain feedback (IEEE Trans. Automat. Control, 1996; 41 : 368–378), and hence takes advantage of both design techniques, while avoiding their disadvantages. In the case that only the output is available for feedback, the performance of the state feedback law is preserved by the use of a fast observer. An open‐loop exponentially unstable fighter aircraft is used to demonstrate the effectiveness of the proposed control design method. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
15.
异丙酚静脉全麻复合硬膜外腔阻滞麻醉期间CO2气腹对血流动力学和氧耗的影响 总被引:4,自引:0,他引:4
OBJECTIVE: To investigate the effects of intraperitoneal CO2 insufflation on the hemodynamics, oxygen consumption (VO2) and carbon dioxide production (VCO2) during intravenous anesthesia with propofol in combination with epidural block. METHODS: Intratracheal intubation was performed after rapid induction of anesthesia and mechanical ventilation was given. Maintenance of anesthesia was achieved using continuous intravenous propofol infusion (2 mg/kg/h) ?N2O inhalation and intermittent epidural administration. Indices of hemodynamics and respiratory function were collected 5 min before induction, 1 min before CO2 insufflation, and 5, 10, 20, 30, 40, 50, 60 min after the start of insufflation and 5 min after the termination of insufflation. RESULTS: The mean arterial pressure (MAP), heart rate (HR), end-tidal PCO2 (P(ET)CO2), VO2 and VCO2 1 min before insufflation were markedly reduced(P<0.01), compared with those recorded before induction. MAP and HR did not undergo any conspicuous changes during CO2 insufflation and 5 min after insufflation termination. Compared with that 1 min before insufflation, PETCO2 was significantly increased 20 min after the start of insufflation (P<0.01), and subsequently carried on the increase though of a lesser scale. VO2 and VCO2 gradually rose after the start of insufflation, and VO2 presented a significantly elevation (P<0.01) 10 min after the insufflation while VCO2 did not show this marked increase(P<0.05) till 20 min after the insufflation in comparison with the levels before insufflation. Subsequently, VO2 continued to rise and VCO2 also retained the increase but of smaller magnitude. CONCLUSION: Intravenous propofol anesthesia combined with epidural block assisted by well-managed excessive ventilation before insufflation can alleviate the adverse effects of CO2 insufflation on respiratory and circulatory systems. 相似文献
16.
赤芍总苷对沙土鼠全脑缺血再灌注损伤的保护作用 总被引:3,自引:0,他引:3
OBJECTIVE: To study the protective effects of the total paeony glycoside (TPG) against global cerebral ischemia-reperfusion injury in gerbils. METHODS: Gerbils models of global cerebral ischemia-reperfusion injury were prepared by bilateral common carotid artery ligation for 12 min followed by 24-hour reperfusion. The effects of TGP on brain edema index, superoxide dismatase (SOD) activity and malonaldehyde (MDA) concentration of the cerebral tissue homogenate and pathology of the brain were examined 24 h after model establishment. RESULTS: Compared with the model group, TPG at the doses of 200 and 400 mg/kg could significantly relieve brain edema, enhance SOD activity and lower MDA concentration in the gerbils. Pathological examination showed that the gerbils with TPG treatment had milder injury of the cells in the hippocampal CA1 region. CONCLUSIONS: TPG has obvious protective effects against global cerebral ischemia-reperfusion injury. 相似文献
17.
外伤性延迟性脾破裂的诊断和治疗(附21例报告) 总被引:1,自引:0,他引:1
目的探讨外伤性延迟性脾破裂的发病规律、临床特点、诊断和治疗方法。方法结合国内外资料及本组病例进行回顾性分析。结果明确诊断16例,误诊为肝破裂2例,宫外孕破裂2例,脾肿瘤1例。21例均手术治疗,行脾切除14例,其中保留副脾2例;脾切除加自体脾组织网膜内移植术3例;脾缝合修补术3例;脾部分切除术1例。死亡1例,原因有就诊晚、失血性休克。结论本病由于腹腔内出血与受伤时间间隔长,容易误诊。诊断除依靠病史、临床表现外,应及时进行腹腔穿刺、B超及CT检查。治疗以脾切除为主,可根据病情、脾破裂的程度以及是否有合并伤等情况采取保脾手术。 相似文献
18.
Wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) is a rarely reported syndrome. There is dispute about whether WEBINO is caused by a pontine or a midbrain lesion and whether the medial rectus subnuclei are implicated. In a study of the clinical and imaging features of four patients with WEBINO, we found that that three of four lesions involved the midbrain but not necessarily the medial rectus subnuclei. 相似文献
19.
Lin Bo Wang Jian Guo Shen Li Feng Dong Chao Yang Xu Wen Jun Chen Shu Duo Xie Xiang Yang Song Ning Dai Xiao Ming Yuan 《Journal of gastrointestinal surgery》2008,12(8):1359-1363
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study
was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness
for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively
evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When
pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic
local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early
gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had
SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic
local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative
procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric
cancer. 相似文献
20.
冯玲 《国际泌尿系统杂志》2009,30(6):391-393
维持性血液透析患者血清甲状旁腺激素(Parathyroid hormone,PTH)水平显著增高,PTH与患者心功能下降、营养状态恶化以及死亡率的增加密切相关.然而,临床实践发现,部分慢性肾脏疾病(Chronic kidney disease,CKD)3-4期、甚至CKD1期的患者血清PTH水平也增高,PTH对此类患者的影响如何,目前报道较为少见.本文结合文献就FTH对非透析CKD患者的心血管系统、骨代谢、营养状况及预后的影响作一综述. 相似文献