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991.
992.
993.
John Nicholas 《Journal of interferon & cytokine research》2005,25(7):373-383
Most herpesviruses of the beta and gamma subfamilies encode homologues of cytokines and chemokine receptor- related G protein-coupled receptors (GPCRs). The roles of these proteins during normal virus replication in the infected host have not been defined in most cases, but the available data and extrapolation from what is known about the properties and functions of their cellular counterparts indicate that they play primary roles in immune evasion or in activating cellular signaling cascades that enhance virus productive replication. Cytokines and chemokine receptors specified by the two human gammaherpesviruses, human herpesvirus 8 (HHV-8) and Epstein-Barr virus (EBV), are the subject of this review. HHV-8 encodes three chemokines, a homologue of interleukin-6, and a CXCR2-related chemokine receptor, while EBV encodes a distinct GPCR and a homologue of interleukin-10. While these viral cytokines and chemokine receptors no doubt contribute to virus biology, their properties indicate that they may also be involved in virus-induced neoplasia. This review discusses the properties, functions, and likely roles of HHV-8 and EBV cytokines and chemokine receptors in relation to both virus biology and virus-associated disease. 相似文献
994.
[目的]应用固体滴定技术监测羟基磷灰石(Hydroxyaptite,HA)的溶解平衡过程,观察组织液生理浓度CO2对羟基磷灰石溶解度的影响.[方法]在恒温水浴系统中以HA为固体滴定物.测试液为KCl溶液(0.1 mol/L),并引入恒定分压的CO2(占空气体积比为3.5%±0.1%).半导体二极管激光为发射光源,散射光源探测器用于监测HA的溶解平衡过程并判断超越溶解平衡点所出现的沉淀(合共17次滴定终点).固体滴定总量用于代表溶解度等温线上的数据点.[结果]引入恒定分压CO2后测定的HA在KCl溶液中的溶解度高于其在KCl溶液中所得50倍以上.[结论]固体滴定技术利于监测HA的溶解平衡过程.溶液体系中CO2增加HA的溶解度.推测该现象与CO2-3形成的复合物密切相关. 相似文献
995.
996.
A case of esthesioneuroblastoma with an unusual clinical and radiographic presentation is reported. The presenting symptoms as well as the computed tomographic examination were compatible with a primary intracranial mass. 相似文献
997.
Priapism: a refined approach to diagnosis and treatment 总被引:4,自引:0,他引:4
The recent introduction of intracorporeal injections of papaverine and phentolamine for the diagnosis and treatment of impotence has resulted in an increased incidence of iatrogenic priapism. Based on our research into penile hemodynamics we propose a refined approach to all types of priapism. Intracorporeal blood gas and pressure monitoring should be used to differentiate ischemic (low flow) from nonischemic (high flow) types. Most cases of papaverine-induced or phentolamine-induced priapism will respond to aspiration alone or in combination with intracorporeal instillation of a diluted alpha-adrenergic agent. In spontaneous priapism alpha-adrenergic agents can be tried first if patients have only mild or no ischemia. In patients with severe ischemia stagnant blood should be evacuated and a shunt procedure should be performed to allow metabolic replenishment of tissue. Intracorporeal pressure monitoring will help to determine the size and number of shunts needed to re-establish corporeal circulation. 相似文献
998.
W. Ziegler D. von Cramon 《European archives of psychiatry and clinical neuroscience》1986,236(1):44-49
Summary This paper deals with a particular aspect of speech motor control in patients suffering from apraxia of speech. Three experiments are reported concerning the phase relations between individual speech gestures. These include the timing of laryngeal, velar and labial movements relative to lingual gestures.A total of 8 patients and 12 normal controls were examined using speech material which was designed according to appropriate phonetic paradigms. Evaluation was performed on the basis of speech signal parameters referring to the kinematics of inter-articulatory phasing. Deviations of the patient group were found in all three experiments. This suggests that disturbed phase relations of individual speech movements are a general feature of apraxic speech. It is further hypothesized that the described motor symptoms are the origin of a variety of phonemic errors. Support for this view is provided by appropriate examples which refer to the examined paradigms. By this argument, much of the disturbed phonemic structure of apraxic speech may be accounted for by timing deficits. 相似文献
999.
Osteomalacia and bone disease arising from aluminum 总被引:2,自引:0,他引:2
1000.
Edda TÖPFER-PETERSEN Johanna AUERBECK Angelika WEISS A.E. FRIESS and W.-B. SCHILL 《Andrologia》1986,18(3):237-251
An antiserum to the purified porcine outer acrosomal membrane (OAM) was raised in female Balb/c mice and was characterized by means of an indirect ELISA. The hyperimmune serum reacted selectively with the acrosomal cap of the sperm head and showed an extremely good cross reactivity with bull and human spermatozoa when assayed by indirect immunofluorescence. Immunoelectron microscopy using the protein A-gold method further confirmed the specificity of the anti-OAM-antiserum for the OAM. In an effort to identify the OAM antigens recognized by the hyperimmune serum and to analyse the extent of cross reactivity on a molecular level, the SDS-extractable proteins were separated by SDS-PAGE, transblotted and immunoprinted using an 125J-conjugated anti-mouse-antibody. To facilitate functional and structural analysis of distinct OAM-proteins monoclonal antibodies were generated by hybridization of mouse myeloma cells with the splenocytes of female Balb/c mice immunized with the purified OAM. One fusion resulted in about 100 anti-OAM-antibodies secreting hybridoma cultures, of which about 30% showed cross reaction with human and bull spermatozoa. Four stable cell lines were selected for this study secreting antibodies directed against the outer acrosomal membrane of boar spermatozoa. Whereas the polyclonal immune mouse serum stained the entire acrosomal cap, the four hybridoma antibodies generated a patch-work-like immunofluorescence pattern over the acrosome. HPLC-ELISA of the solubilized OAM revealed first information on the nature of the corresponding membrane antigen. 相似文献