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21.
目的探讨T细胞非特异性活化在CNS脱髓鞘性疾病中的作用。方法分离实验性自身免疫性脑脊髓炎(EAE)易感性BALB/c小鼠外周血单个核细胞(PBMC),采用体外细胞培养方法在体外与碱性髓鞘蛋白(MBP)共培养,测定培养上清液中IFN-γ、NO水平。结果经MBP刺激的PBMC产生IFN-γ[(43.83±6.06)pg/mL]和NO[(180.76±20.75)μmol/L]明显增加,与对照组产生的IFN-γ[(28.52±2.18)pg/mL]和NO[(95.61±13.09)μmol/L]相比差异有统计学意义(P<0.01)。结论在CNS脱髓鞘性疾病发病过程中,活化的T细胞、单核细胞等分泌致炎细胞因子和其他有害物质增多。 相似文献
22.
广龙昊膏药对大鼠腰椎间盘突出模型细胞因子IL-1、NO及组织胺的影响 总被引:2,自引:1,他引:1
为探讨IL-1、NO及组织胺在腰椎间盘突出中的作用及广龙昊膏药的治疗效果,将60只大鼠造模并随机分为正常组(A组)、造模组(B组)、广龙昊膏药组(C组)和奇正止痛膏组(D组),观察其神经根周围局部组织中IL-1、NO及组织胺的含量。结果显示,B组中的IL-1、NO及组织胺较A组显著升高(P〈0.01)。C组、D组较B组明显下降(P〈0.01)。表明大鼠腰椎间盘突出模型中细胞因子IL-1、NO及组织胺明显增加可能是腰椎间盘突出中的潜在始动或促进因素,而C组能显著降低神经根局部中IL-1、NO及组织胺的含量,说明广龙昊膏药作用部分是通过抑制炎性细胞因子的活性实现的。 相似文献
23.
Sachiko Goto Akiyoshi Tsuji Teiko Murai Minoru Nishida Hiroko Tsukano Haruo Watanabe 《Journal of infection and chemotherapy》1998,4(1):16-19
Although there are effective antibacterial agents against plague, newer antibacterial agents have been developed which show
more potent activity against other bacterial organisms, but have not been tested againstYersinia pestis. A strain ofYersinia pestis was selected (no. 22; National Institute of Infectious Diseases, Tokyo, Japan) that caused a systemic infection in mice.Y. pestis no. 22 was intraperitoneally inoculated into DDY-strain mice, and 13 oral or 6 injectable antibacterial drugs given to the
infected mice at varying doses 1 and 24 hours after infection. Levofloxacin, sparfloxacin and ofloxacin were the most effective
oral agents against the infection, and prulifloxacin and pazufloxacin were also effective but to a lesser extent. Also, gentamicin
and arbekacin were the most potent injectable antibacterial agents againstY. pestis. These results suggest that there are several new drugs, both oral and injectable, which exert excellent in vivo antibacterial
activity against a mouse infection model and may be useful for the clinical treatment of plague. 相似文献
24.
James H. McKerrow 《Perspectives in Drug Discovery and Design》1995,2(3):437-444
Summary Papain family cysteine proteases function primarily intracellularly in higher eukaryotes, but are often extracellular proteases in protozoan helminths. The utility of this class of enzymes is reflected in the diversity of functions they perform in both parasite life cycles and the pathogenesis of parasitic diseases. Examples include secretion of proteases into the gut of parasitic worms for hemoglobin degradation, release from the surface of nematodes to degrade cuticular proteins during molting, and facilitating excystment of protozoa. 相似文献
25.
J.I. Smedberg E. Lothigius I. Bodin A. Frykholm K. Nilner 《Clinical oral implants research》1993,4(1):39-46
In order to satisfy the need to restore the aesthetics, phonetics and comfort and to facilitate optimal hygiene procedures, 20 edentulous patients were treated with a new concept of overdenture therapy on implants ad modum Brånemark. After 24±3.5 months the patients were re‐examined. They were asked to answer a questionnaire and use a Visual Analogue Scale (VAS) to give their opinion on the prosthetic treatment. The results indicate that an implant‐retained overdenture in the maxilla with this design can satisfy the patients needs in aesthetics, phonetics and comfort and can 1 facilitate oral hygiene measures. 相似文献
26.
放射性肝纤维化过程的定量研究 总被引:6,自引:0,他引:6
经^60Coγ线照射大鼠肝区,通过光镜、电镜和图像分析仪、宣研究了照后1年肝脏的病理改变。结果表明,30Gy组在照射后1年内逐渐发生了放射性肝纤维化病变。在肝纤维化发生过程中,肝细胞内糖原颗凿含量进行性减少,间质中胶原纤维含量进行性增加,网状纤维于照射1-3个月呈进行性增加。 相似文献
27.
Many important pharmaceutical agents, including vancomycin, bleomycin, cyclosporin, and several antibiotics, are produced by non‐ribosomal peptide synthetase (NRPS) enzymes in microorganisms. The NRPS pathway produces an extensive library of products using multienzyme complexes acting in an assembly‐line fashion. Engineering an NRPS system to produce an even greater variety of products, some of which may also have beneficial therapeutic value, would be an enormous advantage. Several approaches have been successful in generating novel NRPS products: mutational biosynthesis during which nonnatural substrates are fed to an organism; domain and module swapping between different species to generate hybrid enzymes; and rational site‐directed mutagenesis, based either on phylogeny or computational prediction, intended to switch substrate specificity and produce altered products. This review will highlight the progress in these areas and describe research in the future that will extend the capacity for re‐engineering NRPS systems. Drug Dev. Res. 66:9–18, 2006. © 2006 Wiley‐Liss, Inc. 相似文献
28.
随着生物医用材料研制和医学的迅速发展,以及生活水平、医疗保健、康复水平的提高,人们对自身组织、器官及骨骼缺损的修复和置换方面的要求日益提高,尤其对人造骨骼和人工关节的需求越来越广泛。由于计算机断层成像技术CT(computed tomography)已经成为显示和研究人体内部结构非常有用的手段,将计算机辅助设计技术CAD(Computer aided design)和计算机辅助工程CAE(Computer aided Engineering)等相关技术应用于人造骨骼和内置假体的设计,不仅可以提高产品的设计质量,同时,结合CT和计算机三维重建方法, 相似文献
29.
Design and conduct of occupational epidemiology studies: III. Design aspects of case-control studies
Currently available approaches for the design of occupational case-control studies are reviewed. An accompanying paper reviews methods of analysis. We commence by drawing a distinction between cohort-based and registry-based studies. Methods for selecting cases and controls are then reviewed, including cumulative incidence and incidence density sampling, matching, sources of controls, and issues in control selection. Finally, the advantages and disadvantages of the case-control approach are summarized. 相似文献
30.
Dr. med. Dr. med. dent. Christof Holberg Katja Schwenzer Ingrid Rudzki-Janson 《Journal of orofacial orthopedics》2005,66(2):110-121
Abstract
Background and Aim:
The prediction of soft tissue esthetics is important for achieving an optimal esthetic outcome in orthodontic treatment planning. Applicable procedures have so far been restricted to two-dimensional profile predictions that have not proven to be very reliable. The goal of this investigation was therefore to develop a novel finite element-based procedure that allows a three-dimensional, easily visualized, quantitative analysis and prediction of soft tissue behavior for the clinician. The procedure to be developed should be easy to handle and not entail any additional radiation exposure for the patient.
Material and Methods:
Using a three-dimensional scanner, the facial surfaces of 20 probands were digitalized and individual FEM models were generated.
Results:
After reduction of data redundancy via several conversion steps, a patient-specific simulation model was prepared consisting of 20,000 to 40,000 individual elements to which specific physical properties could be assigned. The average time required for generating a virtual model was 50 minutes. Problems occurring during model generation were rare (mainly shadowing phenomena and movement artifacts).
Conclusion:
The procedure outlined herein makes the reliable generation of patient-specific simulation models possible for facial soft tissue prediction in orthodontics. 相似文献