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81.
Cytologic evaluation of the CSF is often difficult when trying to distinguish between truly neoplastic and reactive cells. Several non-neoplastic conditions may be associated with atypical cells in the CSF, a fact the clinician has to consider to avoid inadequate aggressive theraphies. We report here three patients with infectious meningitis (due to Herpes zoster virus in two, and neuroborreliosis in one) and cytologically atypical cerebrospinal fluid lymphocytes. Further characterization showed that the pleocyrosis in these patients was of reactive origin. Cytomorphology is frequently insufficient and histochemical, immuncytochemical and cellular genome analysis techniques may help differentiate atypical reactive cells from neoplastic cells. 相似文献
82.
Hidetaro Mori Keisuke Hiraoka Ryoichi Yorifuji Tohru Iwasaki Syuzo Gomikawa Ohshi Inagaki Seishi Inoue Yoshihiro Takamitsu Yoshikazu Fujita 《Artificial organs》1994,18(10):725-728
Abstract: The adsorptive characteristics of 5 dialysis membranes for recombinant human erythropoietin (EPO) were studied in vitro in a closed circuit system. For 120 min, EPO added with bovine serum was significantly adsorbed by polymethylmetacrylate (PMMA) and polyacry–lonitrile (PAN) membranes but not by Cuprophan, ethylene vinyl alcohol (EVAL), or polysulfone (PS) membranes. In addition the EPO adsorptive rate, as well as that of β2 –microglobulin (β2 –MG), was greater with a PMMA membrane than with a PAN membrane. EPO was not detected in the ultrafiltrate at 15 min with 5 membranes. These results indicate that EPO was eliminated by membrane adsorption only with some dialysis membranes. 相似文献
83.
Hitoshi Tajiri M.D Kosuke Kozaiwa M.D Tokuzo Harada M.D Yoshikazu Ozaki M.D Kazunori Miki M.D Kazuo Shimizu M.D Shintaro Okada M.D. 《Pediatrics international》1991,33(3):323-326
We assessed the efficacy of a government-sponsored mass protection program in Osaka, Japan, for perinatal HBV infection in infants born to HBeAg positive HBV carrier mothers. We also evaluated the impact of optional follow-up procedures in such infants, including an evaluation of anti-HBs response and a booster dose of HBV vaccine for poor responders. The results demonstrated that this mass protection program protected 94.4% of the infants from perinatal HBV infection in the Osaka area. However, the proportion of infants with an unprotective level of anti-HBs was higher in the standard group than in the follow-up group both at 1.0 and 1.5 years of age, which was also the case for HBV events. Furthermore, the present study showed that a booster dose of vaccine in poor responders was very effective in promoting an anti-HBs response. In conclusion, we recommend that a follow-up blood test to confirm a response of anti-HBs to HBV vaccine should be performed at 4–8 weeks after the third injection of HBV vaccine in infants born to HBeAg positive HBV carrier mothers. We also recommend that a booster injection of HBV vaccine should be immediately given to poor responding infants who otherwise are at a considerable risk of developing HBV infection in late infancy. 相似文献
84.
Role of intracortical mechanisms in the late part of the silent period to transcranial stimulation of the human motor cortex 总被引:3,自引:0,他引:3
J.P. Brasil-Neto A. Cammarota J. Valls-Solé A. Pascual-Leone M. Hallett L. G. Cohen 《Acta neurologica Scandinavica》1995,92(5):383-386
Transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (TES) of the human motor cortex produce a silent period (SP) following motor evoked potentials (MEPs). The early part of the SP can be explained by decreased alpha motor neuron excitability, whereas the late part is presumably due to suprasegmental mechanisms. In order to determine the level of the suprasegmental contribution to the generation of SPs, we recorded excitatory and inhibitory responses to TMS, TES, and percutaneous electrical brainstem stimulation (PBS) in the voluntarily activated first dorsal interosseous muscle of the hand. Stimulus intensities were set so that PBS and TES induced MEPs with areas equal to or larger than those of MEPs obtained with TMS. This procedure revealed that SPs were 49% and 83% shorter with TES and PBS, respectively, than with TMS. As TMS is more effective than TES or PBS in activating cortical interneurons, these findings support the idea that a significant component of the SP arises from intracortical mechanisms. 相似文献
85.
目的 获得丙型肝炎病毒 (HCV) H株包膜糖蛋白的重组杆状病毒 ,在昆虫细胞中稳定表达包膜糖蛋白 E1和 E2 ,并初步应用于丙型肝炎患者血清抗体的检测。方法 用 PCR方法自 HCV H株扩增出包膜蛋白 E基因 ,构建重组杆状病毒 ,并在昆虫细胞中稳定表达包膜糖蛋白 E1和 E2。免疫荧光及 Western blot方法鉴定表达产物。用表达的 E1和 E2蛋白与 35例丙型肝炎患者血清反应。结果 昆虫细胞中表达的 E蛋白呈现 3种分子大小 ,E1的相对分子量为 2 1× 10 3和 33× 10 3 ,E2的相对分子量为 6 0× 10 3。在 35份感染者血清中 ,有 4例 E1抗体阳性 ,其中 1例检出 E2抗体。在 9例 PCR检测 HCV RNA阳性而抗 HCV检测阴性的血清中 ,有 3例血清与表达的 E蛋白反应。结论 HCV E蛋白基因可在昆虫细胞中稳定表达 ,表达的 E1和 E2蛋白可用于 HCV患者的血清学诊断 相似文献
86.
目的 通过测定生长激素缺乏症 (GHD)患儿用国产重组人生长激素 (recom bined hum angrowth horm one,rh GH)治疗时血清生长激素抗体 (GH- Ab)水平及其结合特性 ,探讨 rh GH的免疫原性及其对疗效的影响。方法 对 6 1例 (男 49例 ,女 12例 ) GHD患儿用国产 rh GH治疗 ,每晚睡前皮下注射 rh GH 0 .1IU /kg共6个月 ;用放射免疫法测定治疗期间患儿血清 GH- Ab水平和滴度 ,并计算抗体结合容量、亲和常数 (Ka)。结果 48%患儿 (2 9/6 1)用药后 3个月血清 GH - Ab呈阳性至试验结束时仍未消失 ,其中 2 0例抗体为弱阳性 (结合率 <10 % ) ,9例呈强阳性 (结合率 >15 % ) ;5 2 %患儿 (32 /6 1)治疗期间抗体为阴性 ;血清 GH- Ab的结合容量、Ka及滴度均为低水平 ,分别为 (0 .1~ 4.8) pmol/L、(1.7× 10 7~ 6 .5× 10 8) L /mol和 1∶ 4~ 1∶ 8。GH- Ab阳性患儿治疗后的身高、身高增长速率及身高落后于正常 SD值的变化与同期阴性者比较无统计学差异 (P>0 .0 5 )。结论 本试验所用国产 rh GH对 GHD患儿身高增长具有确切的促进作用 ,其免疫原性所导致产生的 GH - Ab未对患儿体格线性增长产生负性影响 相似文献
87.
J. Viac C. Goujon L. Misery V. Staniek M. Faure D. Schmitt A. Claudy 《Photodermatology, photoimmunology & photomedicine》1997,13(3):103-108
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response. 相似文献
88.
腺病毒介导的HSV—tk基因治疗大鼠脑胶质瘤实验研究 总被引:4,自引:0,他引:4
目的:带有HSV-tk基因的重组腺病毒(AdHCMV-tk)结合核苷类似物(NA)治疗大鼠C6脑胶质瘤。方法:用X-gal染色测定AdHCMV-lacZ转染大鼠C6胶质瘤细胞的效率。用AdHCMV-tk/ACV、GCV离体及活体治疗大鼠C6胶质瘤。结果:AdHCMV-lacZ感染C6细胞效率达100%,AdHCMV-tk感染C6细胞,在病毒感染复数为1000时,GCV和ACV半致死剂量分别为3μg/ml和20μg/ml,Ad-HCMV-tk/ACV治疗大鼠C6胶质瘤模型,大鼠生存期超过90天,而对照组分别为17.0±1.6天(生理盐水组)、14.5±1.3天(AdHCMV-lacZ组),P<0.001。结论:重组腺病毒对靶细胞感染效率可达100%,AdHCMV-tk用GCV的杀伤C6胶质瘤细胞比ACV强,而HSV-tk/ACV用腺病毒介导治疗大鼠脑肿瘤疗效显著。 相似文献
89.
90.
目的:探讨EB病毒(EBV)感染与非鼻咽部T细胞淋巴瘤的关系。方法:用单克隆抗体UCHL-1、L26及EB病毒编码的潜在膜蛋白-1(LMP-1),免疫组化染色确定肿瘤的免疫表型及EB病毒转化蛋白的表达。采用原位杂交方法检测EBV编码的EBERs。结果:21例非鼻咽部T细胞淋巴瘤EBERs5例阳性的(23.8%),其中给内淋巴瘤3例,肺和胃肠淋巴瘤各1例。阳性细胞约占肿瘤细胞的10%~70%。5例EBERs阳性病例中仅1例表达LMP-1,为结内淋巴瘤。结论:非鼻咽部T细胞淋巴瘤可能与EBV的感染有关,LMP-1的阳性率较EBERs低。 相似文献