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静脉溶栓联合导管碎栓和切栓治疗急性大面积肺栓塞   总被引:3,自引:0,他引:3  
目的评价静脉溶栓联合导管碎栓和切栓治疗急性大面积肺栓塞的临床疗效和安全性。方法对19例急性大面积肺栓塞患者,采用下腔静脉滤器置入、肺动脉导管碎栓和静脉溶栓加低分子肝素抗凝治疗,19例中4例加用了Straub Rotarex导管血栓旋切术。结果19例共行21次治疗。18例经介入治疗后胸闷、紫绀症状均明显改善,肺动脉中央分支血流恢复通畅,血氧饱和度由术前平均86%(74%~96%)上升到治疗后的平均97%(94%~100%)。肺动脉压力从术前的(334-5)mmHg(1mmHg=0.133kPa)下降到术后的(254-5)mmHg(t=13.2,P〈0.01)。l例双侧肺动脉主干大块血栓栓塞的患者,介入治疗无效,后经胸外科手术取栓未能成功,患者死亡。4例成功地采用了Straub Rotarex旋切治疗肺动脉血栓,未出现并发症。结论采用导管碎栓和血栓旋切等介入技术联合静脉溶栓抗凝治疗,是治疗急性大面积肺动脉栓塞的有效而且安全的方法。  相似文献   
23.
PURPOSE: The purpose of this pilot study was to test a new Le Fort I internal distraction device. PATIENTS AND METHODS: A new internal Le Fort I distraction device designed by 1 of the authors was used in 3 patients with cleft lip and palate and severe maxillary hypoplasia who needed maxillary advancements in excess of 12 mm. Presurgical planning used CASSOS (SoftEnable Technology, Ltd, Hong Kong SAR, China) prediction tracing software and a stereolithographic model to calculate the distraction vector. The distractors were pre-bent and installed on the stereolithographic model and activated to advance the maxilla. Surgery was performed in a conventional manner, and distraction was started after a 7-day latency phase at the rate of 1 mm/day and continued until the presurgical plan was achieved. The distractor was removed after a 3-month consolidation phase. Cephalometric radiographs were taken at the completion of each phase. RESULTS: This new Le Fort I internal distraction device successfully distracted the maxillae as planned in all 3 patients. At the end of the distraction phase, the maxillary advancement was measured at 15.8 mm, 15.8 mm, and 13.5 mm, respectively. In each patient, a clockwise rotation of the maxilla was observed with a tendency to a posterior open bite. Postoperative radiographs also showed that the actual distraction vectors differed from the planned vectors. After the consolidation phase, radiographs showed a relapse of 2.6 mm, 0 mm, and 5.0 mm, respectively. There was no further relapse on 3-month follow-up radiographs. Each case showed radiographic evidence of excellent new bone formation at the osteotomy sites. CONCLUSION: The new Le Fort I internal distraction device produced the necessary advancement in all 3 patients. The study also showed that the actual distraction vector differed from the planned vector. This discrepancy was caused by a clockwise rotation of the maxilla during the distraction. Finally, the study showed a variable relapse rate not previously reported in maxillary distraction.  相似文献   
24.
Polyclonal antibodies directed against human recombinant basic fibroblast growth factor were used in immunohistochemical studies to localize this growth factor in normal and wounded rat skeletal muscles. According to the intensity of the stain, three main classes of fibers could be identified: the strongly, moderately, and weakly stained fibers. Basic fibroblast growth factor immunoreactivity was found mainly in the extracellular matrix, primarily in the endomysium, which includes the heparin-containing basal lamina, and also in the capillary basal membrane of both normal and wounded muscles; however, the signal intensity was much stronger in normal muscles. The distribution of basic fibroblast growth factor in wounded muscles became markedly heterogeneous and sparse. After 4 hours of ischemia, about 40% of skeletal muscle fibers lost their basic fibroblast growth factor immuno-reactivity. Muscles which underwent 4 hours of ischemia and 24 hours of reperfusion had only a diminished basic fibroblast growth factor immunoreactivity. The pathologic results supported the concept of destroyed cell connection and fiber necrosis in ischemic and reperfused muscles. Potential mechanisms involved in this reduced concentration of basic fibroblast growth factor in wounded muscles may include oxygen free radical activation, a generalized effect of the inflammatory response, and reduced secretion of endogenous basic fibroblast growth factor. These results are only partially compatible with the established mitogenic role of this growth factor and suggest that a reduction of endogenous fibroblast growth factor may partly contribute to a delay in wound healing.  相似文献   
25.
This study examines the possible beneficial effect of Re-LPS (F515) antiserum on experimental multiple system organ failure (MSOF) in rabbits. The results showed that the plasma LPS level was significantly decreased, and it took a shorter period to clear up LPS in experimental than in control rabbits after receiving Re-LPS antiserum. Pretreatment with antiserum can markedly improve the function of the liver, lungs, kidneys, blood and gastrointestinal tract. The MSOF incidence in the group of rabbits receiving immune sera was only 11.2% and the survival rate was raised by about 40.0%. The results suggest that early passive immunotherapy may neutralize gut-derived endotoxin, inhibit endotoxin-induced mediators release and prevent development of severe complications due to sepsis. It is therefore postulated that LPS core antiserum may provide a prophylactic effect on the development of experimental MSOF.
  相似文献   
26.
Chronic Ethanol Inhibits Inositol Metabolism in Specific Brain Regions   总被引:1,自引:0,他引:1  
Many neurotransmitters and hormones in the nervous system transmit signals through receptors coupled to the poly-phosphoinositide (PI) signaling pathway. In this study, an in vivo protocol with (3H]inositol was used to examine the effect of chronic ethanol administration on inositol metabolism and poly-PI turnover in the cerebral cortex, hippocampus, and cerebellum of mouse brain. C57BL/6 mice were given a nutritionally complete liquid diet containing either ethanol (5%, w/v) or isocaloric sucrose for 2 months. Mice were injected intracerebrally with rH]inositol; after 16 or 24 hr, they were injected intraperitoneally with lithium (8 mEq/kg body weight) to inhibit the inositol monophosphatase (IP1) activity. All mice were decapitated 4 hr after lithium injection. Labeled inositol phospholipids accounted for 16 to 23% of total labeled inositol in different regions of control mouse brain, and the percentages in the hippocampus were consistently higher than the cerebral cortex and cerebellum. In control mice, the percentages of labeled IP, after a 4-hr lithium treatment were 11.5%, 9.9%, and 3.7% for cerebral cortex, hippocampus, and cerebellum, respectively. Chronic ethanol feeding resulted in a significant (p < 0.05) decrease in the percent of labeled IP1 and inositol phospholipids, and this effect was observed in the cerebral cortex and, to a lesser extent, hippocampus but not cerebellum. When ratios of labeled IP1 were expressed against labeled inositol phospholipids as an index of the poly-PI turnover activity, significant decreases in IP/lipid ratios were observed in the cerebral cortex, but not the hippocampus or cerebellum. Although mice killed 24 + 4 hr after the last ethanol feeding would have experienced an 8-hr period of ethanol withdrawal, compared with the 16 + 4-hr group, no differences in IP/lipid ratios were observed between the two time groups. These results illustrate regional differences in the effect of chronic ethanol on inositol metabolism in the brain, but no difference in poly-PI turnover in brain due to ethanol withdrawal.  相似文献   
27.
单体皂甙Rb3自西洋参茎叶皂甙中提取。Rb330mg·kg-1可使麻醉大鼠在体心脏的MAP,±dP/dtmax和LVSP减少。用斑片钳的连细胞电压钳法证明.Rb3300mg·L-1使L、B、T型钙通道的开放时间缩短、开放概率减少,其作用与异搏定37.5mg·L-1相似,与BayK86115μmol·L-1作用相反。确切地证明Rb3对钙通道有阻滞作用。  相似文献   
28.
小鼠卵细胞质内显微注入单精子受精的实验研究   总被引:8,自引:0,他引:8  
杨益寿  熊素芳  龙文  李鸣  夏明珠  汪昌介 《解剖学报》1998,29(4):441-445,I011
为了探讨提高小鼠卵细胞质内单精子注入受精率的方法,选取鼠龄12-14周的健康昆明白小鼠作为精子和卵子的供体,受用ICSI技术,以受精后二细胞卵裂的形成率为指标,了解不同采卵时间,不同微注射针参数及不同培养液对细胞质单精子注入的影响。结果表明,hCG注射后18-19h采卵,用针尖内径为4-5μm,斜面角度为35-40度的微注射针进行ICSI操作受精后卵子置CZB中培养可获得较多的2细胞胚,卵裂率明显  相似文献   
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利用变分原理,从不同角度,讨论了随机微分方程特征问题特征值的性质,给出了其期望值的两个上界估计式。  相似文献   
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