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21.
眼针治疗阵发性室上性心动过速120例的即时疗效观察   总被引:2,自引:0,他引:2  
目的:观察眼针对阵发性室上性心动过速的即时疗效。方法:选择符合诊断标准的门诊患者120例,针其眼针穴区:心区和上焦区。针后30分钟描记心电图,计算心率,观察眼针对阵发性室上性心动过速的影响。结果:显效103例,占85.83%;有效9例,占7.5%;无效8例,占6.66%;总有效率93.33%.结论:眼针对阵发性室上性心动过速有较好的即时疗效。  相似文献   
22.
A new micelle system formed from methoxy (polyethylene glycol)-b-poly (5-benzyloxy-trimethylene carbonate; MePEG-b-PBTMC 5000-b-4800) was investigated as a delivery system for the hydrophobic anti-cancer agent, ellipticine. The ellipticine was loaded into the MePEG-b-PBTMC micelles with a loading efficiency of 95% using a high-pressure extrusion technique. The ellipticine-loaded micelles have a spherical morphology and an average diameter of 96 nm. The anti-cancer activity of ellipticine was confirmed to be retained following formulation in the MePEG-b-PBTMC micelles. The extent of protein adsorption to the MePEG-b-PBTMC micelles was investigated by transmission electron microscopy, dynamic light scattering and gel filtration chromatography. Overall, the amount of protein both loosely and tightly associated with the micelles was found to be minimal and insignificant. The partitioning properties of ellipticine between an aqueous medium containing protein and the MePEG-b-PBTMC micelles were examined over a range of protein concentrations. Under physiologically relevant conditions, it was found that 61% of the drug remained within the micelle fraction while 39% was in the protein-containing aqueous phase. In addition, the in vitro drug release profile of ellipticine from the micelles was fit using a modified Higuchi model and found to be accelerated in the presence of protein. These studies demonstrate that although there are no significant interactions between micelle and protein, the properties of the micelle as a delivery vehicle may be strongly influenced by protein-drug interactions.  相似文献   
23.
利用电化学方法研究医用钛合金在0.9%NaCl生理盐水,模拟人工唾液,模拟人工体液中的腐蚀情况,分析腐蚀电位和腐蚀电流密度,扫面电镜观察腐蚀表面形貌,CA-A型接触角测试仪测试钛合金表面被腐蚀后接触角的变化。实验表明:钛合金在三种生理电解液中的腐蚀情况依次是:模拟人工唾液〉模拟人工体液〉0.9%NaCl生理盐水。扫面电镜观察表明,医用钛合金在0.9% NaCl生理盐水腐蚀后,表面出现了许多腐蚀孔,经模拟人体体液腐蚀后,表面变得粗糙不平整,腐蚀孔数目变化不大,钛合金经人工唾液腐蚀后,腐蚀孔数目增多,部分腐蚀孔孔径明显增大。经三种生理电解液腐蚀后,钛合金表面接触角都减小。结论:医用钛合金在人工唾液中的腐蚀最严重,在临床应用中应给予相应的防范措施。  相似文献   
24.
Abstract:  The risks of developing malignant melanoma (MM) include ultraviolet irradiation and genetic factors. To examine the contribution of rare and common variation within known MM genes in sporadic US MM patients, coding regions of known MM susceptibility genes [cyclin-dependent kinase inhibitor 2A ( CDKN2A ), cyclin-dependent kinase 4, melanocortin 1 receptor ( MC1R ) and tyrosinase ( TYR )] were resequenced in 109–135 MM cases. The significance of variants was examined by comparing their frequencies in 390 cancer-free controls. Potential deleterious mutations in CDKN2A were found in two patients and two others had variants of unknown significance. Cases were more likely than controls to harbour the MC1R 'R' variants known or predicted to alter its function ( P  = 0.002), particularly the R160W variant ( P  = 0.0035). The associated TYR R402Q variant (rs1126809*A) was found in 29% of cases, similar to what has been described previously. One MM patient with a family history of MM, who had developed other skin cancers, was homozygous for a novel TYR variant (P406L) of unknown significance. Hence, rare variants in TYR may be important risk factors for skin cancer.  相似文献   
25.
Ganoderma sinensis has been used widely in Oriental countries for the prevention and treatment of various diseases including cancer. Previous studies have shown that the lipid extract from Ganoderma exhibits direct cytotoxicity against tumor cells. Here, it is reported that the lipid extract from germinating G. sinensis spores, at lower concentrations that have no direct tumoricidal activity, induce potent antitumor immune responses in human monocytes/macrophages. Upon stimulation with the lipid extract, monocytes/macrophages exhibited markedly increased production of proinflammatory cytokines and surface expression of costimulatory molecules. Conditioned medium from stimulated cells effectively suppressed the growth of tumor cells. Apparently, the lipid extract triggered macrophage activation via a mechanism different from that associated with LPS. Moreover, it was observed that the lipid extract could partially re‐establish the antitumor activity of the immunosuppressive tumor‐associated macrophages. These results indicated that in addition to its direct tumoricidal activity, the lipid extract from G. sinensis spores could exert antitumor activity by stimulating the activation of human monocytes/macrophages. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
26.
Pneumocephalus is a very rare complication of video-assisted thoracoscopic surgery (VATS). A 66-year-old man developed pneumocephalus secondary to thoracoscopic excision of a neurogenic tumor in the posterior mediastinum. Pneumocephalus was diagnosed by brain computed tomography. Neurosurgical intervention was performed after conservative therapy had failed. The patient's condition had resolved without any neurologic sequelae 2 years later. When a patient has a relatively large amount of chest tube drainage and neurologic symptoms after VATS, the possibility of pneumocephalus due to cerebrospinal fluid leakage must be considered.  相似文献   
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Erratum     
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30.
The authors reviewed the radiographic manifestations of 17 cases of parosteal osteosarcoma, with pathologic correlation in 15. There were two types of parosteal osteosarcoma radiologically. The majority of cases were type I with uniformly dense masses which had regular borders. They often adhered to the cortex and showed no evidence of soft-tissue invasion which correlated with low-grade pathologic malignancy and a relatively benign clinical course. Type II involved the bone, soft-tissue and the medullary cavity. These lesions were poorly differentiated and frequently accompanied by metastatic lesions.
  相似文献   
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