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21.
赵洪礼  刘军连 《医学争鸣》1990,11(6):409-411
以光敏生物素标记的R3 cDNA克隆为模型,采用正交设计的方法,对影响核酸杂交反应的主要因素:杂交反应温度,反应时间,探针浓度及甲酰胺浓度作了综合性分析。当探针浓度为800μg/L,甲酰胺浓度为10mol/L,50℃杂交反应6h,可获得最高灵敏度(10pg)。  相似文献   
22.
经喉内镜手术治疗喉部疾病的并发症分析   总被引:1,自引:1,他引:0  
目的:分析经喉内镜手术后并发症的发生原冈及其防治措施。方法:使用从德国STORZ公司引进的国内首套喉内镜手术系统,治疗包括声带小结、声带息肉、喉乳头状瘤、声带囊肿、会厌囊肿、喉部炎性假瘤、喉部血管瘤等58例患者,并随访2~36个月,观察主要并发症并作相应处理。结果:58例患者中发音正常者54例,发音功能明显好转者4例。主要并发症有:牙齿松动2例,牙齿脱落1例,声带粘连1例,舌体麻木1例,舌运动障碍1例,术后拔管时喉痉挛1例。结论:经喉内镜手术可住微创的前提下彻底清除病灶,并最大限度地保留发音功能,只要术前严格掌握适应证,术中精细操作,其并发症是可以避免的。  相似文献   
23.
PURPOSE: To validate the deployment, in vivo performance, biostability, and healing capacity of the Anaconda self-expanding endoprosthesis in a canine aortic aneurysm model. METHODS: Aneurysms were surgically created in 12 dogs by sewing a woven polyester patch onto the anterior side of the thoracic or abdominal aorta. Anaconda prostheses were implanted transfemorally for prescheduled periods (1 or 3 months). Aneurysm exclusion and stent-graft patency were monitored angiographically. Healing was assessed with histological analysis and scanning electron microscopy (SEM). Textile analysis determined the physical and chemical stability of the woven polyester material, while the biostability of the nitinol wires was evaluated with SEM and spectroscopy. RESULTS: All prostheses were intact at explantation. After 1 month, endothelial-like cells were migrating in a discontinuous manner both proximally and distally over the internal collagenous pannus at the device-host boundary. After 3 months, endothelialization had reached the midsections of the devices, with a thicker collagenous internal capsule. Patches of endothelial-like cells were sharing the luminal surface with thrombotic deposits. However, the wall of the device at the level of the aneurysm was generally poorly healed, with multiple thrombi scattered irregularly over the luminal surface. The polyester fabric was intact except for some filaments that were ruptured adjacent to the sutures and some abrasion caused by the nitinol wires. No evidence of corrosion was found on the nitinol stents. CONCLUSIONS: This Anaconda stent-graft has demonstrated its ability to exclude arterial aneurysms. The device used in this study was an experimental prototype, and the manufacturer has incorporated new immobilization features into the model for clinical use. The constituent materials appear to be suitable in terms of biocompatibility, biofunctionality, and short-term durability.  相似文献   
24.
目的:研究氧自由基(OFR)及降钙素基因相关肽(CGRP)预处置对OFR所致离体大鼠心脏损伤的拮抗作用.方法:Langendorf法灌流心脏,电解KH液产生OFR.结果:CGRP或OFR预处置减轻OFR所致心脏收缩功能下降,冠脉流量减少和肌酸激酶(CK)释放增加.蛋白激酶C(PKC)抑制剂H7可取消OFR预处置的心脏保护作用(对照组,OFR损伤组,OFR预处置组,H7加OFR预处置组及H7组的CK释放量分别是110±7,215±23,169±14,240±30,113±19U·L-1).结论:OFR或CGRP预处置对OFR所致心肌损伤具有拮抗作用,该作用与PKC激活有关.  相似文献   
25.
目的 研究电阻应变式传感器(RSS)在不同下肢骨折类型手术中的应用。方法 选择2020年10月—2022年8月中国科学技术大学附属第一医院收治的外伤性下肢骨折患者99例,按照骨折类型分为股骨粗隆间骨折组79例、股骨干骨折组15例、股骨颈骨折组5例。患者均在牵引床上行闭合复位内固定术,使用RSS测量3组不同骨折类型手术中的初始牵引力、牵引时长、松解牵引力。记录手术时间、术中出血量,术后评分及3组不同骨折类型手术前后血色素变化及输血情况;比较使用不同内固定方式(长髓内钉、短髓内钉、空心钉)的术中牵引力和手术出血量、手术时间;比较长髓内钉固定患者和短髓内钉固定患者时下肢旋转角度。结果 3组不同骨折类型初始牵引力、牵引时长、松解牵引力、手术时长、术中出血量、术后评分比较,差异均有统计学意义(P <0.05)。3组不同骨折类型术前、术后血红蛋白、红细胞压积比较,差异均有统计学意义(P <0.05)。3组术中输血情况比较,差异有统计学意义(P <0.05),术后输血情况比较,差异无统计学意义(P>0.05)。使用不同内固定方式的患者牵引总时长、年龄、术中出血量、手术时间比较...  相似文献   
26.
59 angiomyolipomas were studied: immunohistochemistry (IHC) was used in 24 cases, electron microscopy (EM) in 6 cases. 57 tumors had a typical structure, 2 did not contain fat component. Premelanosomes were found by EM in one tumor. Smooth muscle actin was found in all tumor cells. Involvement of lymph nodes was observed in 2 patients. Histogenesis of this tumor is discussed.  相似文献   
27.
The aim of this work, that was carried out using Wistar rats, was to characterize the response of neurons of different morphofunctional types to amphetamine administration and to study the possibility of correction of these changes by delta-sleep inducing peptide (DSIP). Single intraperitoneal injection of 60 microg/kg of DSIP following a long term amphetamine administration (2.5 mg/kg for 3 weeks) was shown to result in normalization of brain metabolism, that was disturbed by the drug. The correcting DSIP effect was found in rat brain structures judging by the parameters of the state of proteins in neurons of sensomotor cortex and caudate nucleus and by the activity of enzymes of neurotransmitter metabolism, such as type A and B monoamine oxidases and acetylcholine esterase, that was determined in subfractions of the same brain structures. DSIP modulating effect in phenamine stereotypy supports its role as an adaptogen of intercenter relations in CNS pathology.  相似文献   
28.
Morphology of microparticles of the microencapsulated measles vaccine was studied by cryofractography, transmission electronic microscopy and by atomic force microscopy; co-polymers of polyacrylic acid and of sodium-alginate (spermidine) complexes were used as the matrix. The different-composition microcapsules had clear-cut borders and a certain range of sizes; but they were different in morphology, and their structures and densities varied identically with regard for a medium acidity, which is apparently preconditioned by some conformation-type alterations of matrix molecules. The studied preparations can, probably, protect the viral material in the stomach aggressive medium and release the material to ensure its contact with the intestine lymph tissue; thereof, they can be referred to as promising for further study of mucosal vaccines.  相似文献   
29.
The laboratory verified cases of Crimean-Congo hemorrhagic fever (CCHF) in the piedmont steppes of the North Caucasus (Malgobeksky District, Republic of Ingushetia) are first described. The source of the first infection was Ixodidae ticks; three subsequent sources were contacts with the bloody discharges from patients. CCHF virus genome was detected in the blood of the cattle from an epidemic focus and in the pools of the Ixodes ticks Haemaphysalis parva Neum., 1897 and Boophilus annulatus Say, 1821, taken from cattle. The problem of including the piedmont steppes of the North Caucasus into the CCHF nosological area is discussed.  相似文献   
30.
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