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31.
采用MTT方法观察癌光啉结合^60Coγ射线放射对四株人鼻咽癌细胞体外放射增敏作用,结果表明在一定的PsD007浓度范围内,随PsD007浓度的升高,放射对细胞的杀灭作用明显增强,当浓度分别为1.25,6.25,12.5,25和50μg/ml时,对四株细胞杀灭增加倍数分别为1.01-1.06,1.15-1.29,1.28-1.59,1.79-3.18,2.86-5.55;放射量效存活曲线按多靶单击  相似文献   
32.
济南市德国小蠊对常用化学杀虫剂的敏感性测定   总被引:1,自引:1,他引:0  
目的 :了解济南市德国小蠊 (BlattellaGermanica)对常用化学杀虫剂的抗药性 ,指导科学、合理使用杀虫剂。方法 :药膜接触法。结果 :野外品系德国小蠊与敏感品系比较 ,对氯氰菊酯、溴氰菊酯、残杀威、DDVP的抗性系数分别为 10 .2 2、3 .2 1、1.18、1.19。结论 :济南市德国小蠊对 4种杀虫剂的敏感性不一 ,在害虫防制时须选择使用适当的杀虫剂  相似文献   
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OBJECTIVE: To investigate the factors responsible for Pseudomonas aeruginosa nosocomial cross-infection in the intensive care unit (ICU) and provide effective measure for the prevention and management. METHODS: The homology of 7 Pseudomonas aeruginosa strains isolated from the patients in the ICU and the environment was examined by biological, serological, drug-resistance and plasmid analysis. RESULTS: The results of serological and plasmid analyses had good consistency, which demonstrated that the 7 Pseudomonas aeruginosa strains originated from solution in the oxygen humidifier, with uniform serological and plasmid type, and belonged to the same clone with cross-infection by contact between the patients or nursing staff and the objects in the ICU. CONCLUSION: Serological and plasmid analyses are more practical for identifying the sources of Pseudomonas aeruginosa cross-infection, which can be prevented by strict disinfection of the instrument and supervision of the nursing staff in the ICU.  相似文献   
35.
目的 探讨海水浸泡弹烧复合伤伤后血液细菌学变化与内脏病理学变化之间的关系。方法 建立海水浸泡弹烧复合伤模型后,依模型将15只成年杂种犬随机分为单纯弹烧复合伤组(简称非浸泡组,7只)和海水浸泡弹烧复合伤组(简称浸泡组,8只),于伤后即刻和4、7、10、20、28h共6个时相点抽取静脉血进行血细菌培养。另于伤后28h和濒死期将动物活杀,取心、肝、肺、肾行病理学观察。结果 浸泡组动物菌血症出现较早且严重。导致菌血症的细菌来源复杂,不仅有肠道菌群,还有海水特有菌群和皮肤常驻菌群。在内脏器官组织病理学上,不仅有不同程度的血液循环障碍及退行性变,还有严重的炎症反应。结论 在海水浸泡弹烧复合伤中,伤后出现的严重菌血症进一步加重了内脏器官损伤。  相似文献   
36.
PURPOSE: Survivin, a member of the inhibitor of apoptosis (IAP) family, is not detected in normal adult tissues but is overexpressed in various cancers, including some types of lymphoma. The frequency and prognostic significance of survivin expression in anaplastic large-cell lymphoma (ALCL) is unknown. Materials and METHODS: We assessed for survivin expression in 62 ALCL tumors (30 anaplastic lymphoma kinase [ALK]-positive and 32 ALK-negative) obtained before doxorubicin-based chemotherapy. Given that survivin is a target of the STAT3 signaling pathway and STAT3 is activated in ALCL, survivin expression was also correlated with STAT3 activation. RESULTS: Survivin was expressed in 34 tumors (55%) and did not correlate with ALK. A significant association between survivin expression and STAT3 activation was observed (P =.007, Fisher's exact test). For the ALK-positive group, the 5-year failure-free survival (FFS) was 34% for patients with survivin-positive ALCL compared with 100% for patients with survivin-negative ALCL (P =.009, log-rank test). For the ALK-negative group, the 5-year FFS was 46% for patients with survivin-positive tumors compared with 89% for patients with survivin-negative tumors (P =.03, log-rank test). Overall survival was similarly worse for patients with survivin-positive tumors in both the ALK-positive and ALK-negative groups. Furthermore, multivariate analysis confirmed the independent prognostic value of survivin expression, along with age older than 60 years and Ann Arbor stage III or IV. CONCLUSION: Survivin is expressed in approximately half of ALCL tumors and independently predicts unfavorable clinical outcome. Modulation of survivin expression or function may provide a novel target for experimental therapy in patients with ALCL.  相似文献   
37.
An enzyme-linked immunosorbent assay (ELISA) was used to measured IgG antiboody titers againt a synthetic peptide whose sequence was derived from the glycine-alanine repeating region of Epstein-Barr virus nuclear associated antigen 1 (EBNA-1). Antibody titers were determined in sera from 15 normal subjects, sera from 21 normal male siblings of X-linked lymphoproliferative syndrome (XLP) patients, from 20 XLP patients comprising a total of 42 samples, and ten samples before and ten samples after gamma-globulin therapy in ten patients with XLP. Data analysis demonstrated that while there are differences between the ELISA and ACIF, they appear to measure a similar response as demonstrated by their correlation coefficient (0.77) and the GMT to EBNA observed by both methods. No cross-reactivity of cytomegalovirus antibodies to the EBNA-1 peptide was observed by immunobv using adsorption against AD-169 infected MRC-5 cells.. However, non-specific binding was observed if samples were not pre-incubated in a 10% goat serum PBS-Tween 20 solution. This pre-treatment removed the non-specific binding that falsely elevated GMT in approximately 15% of both normal and XLP samples in ELISA. The ELISA system appears to be a sensitive, reproducible and objective test that may be useful for assessing the antibody responses of patients to the EBNA-1 protein.  相似文献   
38.
本文观察了硝酸钚溶液经腹腔一次注入大鼠体内,不同时间后胸腺淋巴细胞超徽结构损伤效应与修复规律.早期可见淋巴细胞质膜及内膜系统的变化,以后出现核损伤,注后20天损伤最严重。以小淋巴细胞的损伤更明显。注后1月细胞损伤有所减轻,6个月基本恢复正常。  相似文献   
39.
目的探讨眶骨延长术扩大眶容积治疗眼球突出的可行性。方法1年龄山羊6只,环行截开右侧眶壁,于眶上壁放置延长器,侧向延长1.5cm,经大体、X线、干骨标本及组织学观察成骨情况。结果6只山羊眶骨得到不同程度的侧向延长,延长侧随着眶骨容量的增加,眼球突度较自身对照侧为小。结论眶骨延长术可造成山羊眶骨侧向移位,有可能成为治疗眼球过度突出的方法之一。  相似文献   
40.
BACKGROUND/PURPOSE: Abdominal nontuberculous mycobacterial infection is a rare condition. Continuous ambulatory peritoneal dialysis (CAPD)-associated peritonitis is the most common manifestation of infection due to nontuberculous mycobacteria (NTM). There are limited data on the clinical manifestations of nontuberculous mycobacterial infection. This study investigated the diagnostic features, clinical presentation, mycobacteriology, treatment and outcome of all abdominal NTM infections treated over a 7-year period at a major teaching hospital in Taiwan. METHODS: The medical records of all patients with a diagnosis of abdominal NTM infection from January 1997 through to December 2003 were retrospectively reviewed. RESULTS: All 11 patients with abdominal NTM infections identified during the 7-year period were included. Among these patients, six were male and five were female, with a mean age of 64.5 years. The disease manifested as peritonitis (9 patients, 82%), splenic abscess (1, 9%), or perirenal abscess (1, 9%). Most patients (73%) had underlying malignancy, most often hepatoma (45%). Immunocompromised status (liver cirrhosis, malignancy, acquired immunodeficiency syndrome) was noted in 10 patients (91%). None of our patients who developed NTM peritonitis had received CAPD. The peritoneal fluid appearance varied considerably, with no particular predominance of clear, turbid, bloody, or chylous findings. Rapidly growing mycobacteria were the major etiology (46%) of abdominal NTM infection, and Mycobacterium abscessus played a major role (27%). Overall, eight patients died, and only one patient survived longer than 1 year. Seven patients (64%) died before diagnosis. CONCLUSION: Abdominal NTM infection is frequently overlooked because of its rarity and nonspecific symptoms, with consequent delays in diagnosis and treatment. In immunocompromised patients with ascites from any cause (liver cirrhosis, malignant ascites, etc.), NTM peritonitis should be considered early in the differential diagnosis of symptoms including fever, abdominal pain and weight loss. The poor prognosis of abdominal NTM infection appears to be related to the severity of underlying conditions, most often malignancy.  相似文献   
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