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91.
小包装全氟丙烷气体动力学实验研究   总被引:1,自引:0,他引:1  
为检验塑料小包装全氟丙烷气体(C3F8)在不同包装和储存方法时浓度变化,将装有5~7mlC3F8的聚氯乙烯小袋,根据不同储藏温度和外包装方法随机分成四组:(1)22℃聚乙烯外包装,(2)36℃聚乙烯外包装,(3)22℃铝箔真空外包装,(4)-29℃聚乙烯外包装;每一组C3F8小袋气体存放一定时间后,应用气相色谱分析方法进行浓度测量。结果:第3组C3F8浓度最高和稳定,第2组浓度随放置时间降低最明显,第4组是临床应用气体的储藏和包装方法,其30天样本浓度和第3组相等,但放置一年时浓度降低。结果显示:塑料小包装C3F8予以铝箔真空外包装是一种可行的方法,利于C3F8运输和普及;聚乙烯外包装的C3F8,应放在-29℃保存,时间不超过一年。  相似文献   
92.
CT导引下肝肾囊肿抽吸硬化治疗   总被引:6,自引:0,他引:6  
目的:总结CT导引下肝肾囊肿穿刺抽吸硬化治疗的疗效和操作经验。材料和方法:肝囊肿11,肾囊肿15例,多囊肾1例,囊肿大小为3.5-12cm,均用15cm长20GGreene针穿刺治疗,抽出囊液量为21-550ml,囊液抽净后注入99.7%的无水酒精。结果:治疗后症状均有明显好转或消失,本组随访肝囊肿7例、肾囊肿11例,疗效指数I级1例(多囊肾),Ⅱ级肝肾囊肿各2例,Ⅲ级肝囊肿5例肾囊肿8例。穿刺操作顺利,无严重并发症发生。结论:CT导引下肝肾囊肿抽吸硬化治疗操作简便、创伤小、疗效高可作为替代外科手术的有效的治疗方法,多囊肾的单纯抽吸治疗可明显减轻症状,改善肾功能,是一种较好的治疗手段。  相似文献   
93.
利用电渗析和离子交换柱除去原水中的各种杂质可得到去离子水.而去离子水的质量直接决定了医用注射液的质量。通过近二年的实际操作.列出了与去离子质量有关的主要因素,并提出一些相应见解。  相似文献   
94.
Objective. Rapidly destructive hip disease (RDHD) is an uncommon disorder of the hip that has been considered a disease of unknown cause and distinct from ischemic necrosis of the femoral head. The objective of this study was to investigate ischemic necrosis of the femoral head as one potential cause of RDHD. Design and patients. In 600 patients who underwent MR imaging of the hip, 20 cases of ischemic necrosis involving the entire femoral head in 18 patients (3%) were retrospectively studied with routine radiography and MR imaging. All patients had surgically confirmed ischemic necrosis of the femoral head. Results and conclusions. All patients showed rapid destruction of the femoral head on routine radiography and MR imaging as compared with the gradual onset of clinical symptoms. Plain radiographs showed several bone fragments at the inferomedial aspect of the femoral head (75%), acetabular erosions (55%), eccentric depression at the lateral articular surface of the femoral head conforming to the adjacent acetabulum (35%), and mild osteoarthritis (15%). Bone sclerosis was often present at sites of impaction between the femoral head and the acetabulum. MR imaging showed marked distention of the joint capsule in all cases. In 14 of 20 cases, the contents of the joint space showed predominantly low or intermediate signal intensity on T1- and T2-weighted images. Ischemic necrosis involving the entire femoral head may represent one of the causes of RDHD.  相似文献   
95.
Virus-induced alterations in the cellular expression of chemokines may be important in directing the migration of specific leucocyte subsets to sites of infection, thereby playing a pivotal role in viral pathogenesis. We show here that cytomegalovirus (CMV) infection of human fibroblasts resulted in significantly increased expression of the C-X-C or alpha-chemokine interleukin-8 (IL-8), at both the mRNA and protein levels. Increased IL-8 production was seen following infection with the high passage laboratory CMV strains AD169, Towne, or Davis, as well as the low passage clinical CMV isolates Toledo or C1F. The increase in IL-8 production had functional consequences, as demonstrated by the ability of supernatants from CMV-infected fibroblasts to significantly enhance neutrophil transendothelial migration. The latter was independent of alterations in adhesion molecule expression on the endothelial cells, and was abrogated by neutralizing antibodies specific for IL-8. Direct infection of endothelium with the endothelial cell-tropic CMV strain C1FE, also resulted in enhanced neutrophil transendothelial migration. Neutrophils play an important role in the dissemination of CMV throughout the body, and thus CMV-induced neutrophil recruitment would be expected to enhance CMV dissemination. Increased production of chemokines in response to CMV infection could also disrupt the fine balance between a beneficial and a destructive immune response, thereby potentially contributing to pathology.  相似文献   
96.
目的:比较三种方案治疗小儿细菌性肺炎的效率(即费用-效果)。方法:2001年-2002年采用前瞻性随性临床试验A组50例,B组50例,C组50例作为分析模型,以深圳市二级甲等医院收费为标准,采用决策树的分析方法,进行费用一效果分析。结果:每治疗1例有效病人,A、B、C三组方案的期望成本分别为4707.45元,3052.51元,结论:同时考虑临床疗效及医疗费用,C组有最好的费用-效果,值得临床推广应用。  相似文献   
97.
98.
肩胛皮瓣再造阴茎   总被引:5,自引:0,他引:5  
目的:探索一种新的阴茎再造手术方式。方法:应用肩胛皮瓣游离移植和银丝棒硅胶阴茎假体置入行阴茎再造。结果:自2000年3月起,已在临床应用6例,术后皮瓣全部成活。经随访6-12个月,阴茎形态和功能良好,结论:此手术方法设计合理,术后形态功能良好,供区无明显继发畸形,是一种较好的阴茎再造方法。  相似文献   
99.
3H-胸苷酸掺入法对选择前列腺癌化疗方案的价值   总被引:1,自引:0,他引:1  
目的为临床选择激素难治性前列腺癌(HRPC)的化疗方案提供参考.方法采用3H-胸苷酸(3H-TdR)掺入法检测了20例HRPC细胞对常用化疗药物的敏感性.结果HRPC对单药的体外敏感性依次为足叶乙苷(VP16)>阿霉素(ADM)、5-氟尿嘧啶(5-FU)、雌二醇氮芥(EMP)>长春花碱(VLB)>顺铂(DDP);二药联合可使敏感性进一步提高,依次为EMP加VP1 6、5-FU加ADM>EMP加VLB>5-FU加DDP三药联用抑瘤作用更强,EMP加VLB加APM、5 FU加ADM加DDP>EMP加VLB加DDP.结论3H-TdR掺入法有助于化疗方案的选择,对HRPC以联合化疗效果较好.  相似文献   
100.
OBJECTIVE: To address the issue as to how best to perform statistical MUNE, we applied two different approaches and compared results in healthy subjects and ALS patients. METHODS: Twelve normal subjects (women 8, mean age 52years) and 11 ALS patients (women 4, mean age 54years) underwent two consecutive MUNE studies, which differed in terms of setting and modifying the recording window. These are referred to as the 'expansion' and 'narrowing' methods, respectively. Size-weighted average (Av) SMUP and MUNE values were obtained using the two methods, and compared in control and patient groups. RESULTS: Expansion method-derived Av SMUP sizes and MUNE values differed only slightly from those obtained using the narrowing method in healthy subjects, whereas the narrowing method resulted in significantly larger Av SMUP sizes and smaller MUNE values than the expansion method in ALS patients (Wilcoxon signed ranks test, p=0.003). The sizes of tested areas (mean+/-SD) were significantly larger for the narrowing method than the expansion method in both subject groups with much greater difference in ALS patients; 9.6+/-3.1% vs. 7.9+/-1.7% in healthy subjects and 16.1+/-5.1% vs. 11.2+/-3.0% in ALS patients (Student t-test, p<0.01). CONCLUSIONS: The present study shows, unlike that found in normal subjects, that the results of statistical MUNE in ALS patients are heavily dependent on the approach used to set and modify recording windows. SIGNIFICANCE: The expansion method using a 10%-sized window is likely to suffer from systemic errors due to the ceiling effect and the sampling of artifactually small motor units in ALS patients. The authors recommend that the narrowing method be considered as an alternative that avoids these problems.  相似文献   
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