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951.
Electrodermal Lability and Visual Information Processing 总被引:1,自引:0,他引:1
Individual differences in electrodermal lability have been related to performance in vigilance and reaction time tasks. The goal of the present study was to employ an "additive factors" approach to identify the stages of information processing that might underlie these effects. Nineteen labile and 17 stabile subjects performed a choice reaction time task in which a visual imperative stimulus was presented under two conditions of intensity (presumed to affect the speed of pre-processing operations) X three conditions of degradation (which influences later encoding processes related to feature extraction). Measures of both reaction time and movement time were obtained. The major findings were: (a) labile subjects had faster reaction times than stabiles, and (b) lability interacted significantly with stimulus degradation. Labiles also tended (p less than .10) to have faster movement times. This pattern indicates that labiles and stabiles differ in the performance of later encoding operations, and possibly in the speed of motor processes as well. However, they do not appear to differ in the early pre-processing of the simple physical attributes of a stimulus. 相似文献
952.
Production of tumour necrosis factors by human T cells stimulated by a superantigen,toxic shock syndrome toxin-1
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H. AKATSUKA K. IMANISHI K. INADA H. YAMASHITA M. YOSHIDA T. UCHIYAMA 《Clinical and experimental immunology》1994,96(3):422-426
The capacity of human T cell subsets, CD4+ or CD8+ T cells, to produce tumour necrosis factors (TNF-α and TNF-β) upon stimulation with toxic shock syndrome toxin-l (TSST-I) and the requirement for MHC ctass II molecules on accessory cells (AC) in the response were investigated. The capacity of CD4+ T cells was much higher than that of CD8+ T cells in TSST-1-induced production of TNF-α and TNF-β. The expression of MHC class II molecules on AC was required in the response. 相似文献
953.
血液灌流治疗百草枯中毒临床观察 总被引:1,自引:0,他引:1
目的观察血液灌流治疗百草枯中毒的疗效。方法血液灌流治疗组(治疗组)22例在常规治疗的基础上,采用血液灌流治疗并观察疗效。非血液灌流治疗组(对照组)16例。结果治疗组22例中死亡14例,病死率为63.6%,对照组病死率87.5%,两组相比P〈0.05。结论血液灌流治疗百草枯中毒可提高治愈率,降低病死率,是临床上抢救百草枯中毒较有效的方法。 相似文献
954.
目的:研究血管内皮生长因子(VEGF)、血管生成素-1(ANG-1)、血管生成素-2(ANG-2)、血小板反应蛋白-1(TSP-1)的表达与胆管细胞性肝癌(CCC)血管生成和侵润转移的关系。方法: 对33例手术切除的CCC标本进行CD34、VEGF、 ANG-1、 ANG-2 和TSP-1的免疫组化染色,研究VEGF、ANG-1、ANG-2、TSP-1的表达与胆管细胞性肝癌血管生成和肿瘤门静脉侵犯、肝内转移、淋巴结转移以及肿瘤分化水平之间的关系。 结果: 本组CCC的微血管密度(MVD)为(87.2±52.6)/mm2,VEGF、ANG-1、ANG-2 和TSP-1的阳性率分别为75.6%、36.0%、57.6%和45.5%。VEGF和ANG-2的阳性表达与高MVD相关,TSP-1则与MVD负相关(P<0.01,P<0.05,P<0.01)。阳性TSP-1与肝内转移正相关(46.7% vs 5.6%,P<0.05)。结论: CCC瘤内的血管新生活跃,VEGF和ANG-2的阳性表达与CCC血管生成正相关,TSP-1则与其负相关,TSP-1的阳性表达还与肝内转移相关,VEGF、ANG-1、ANG-2的表达与肿瘤的侵润转移未见显著相关。 相似文献
955.
Breast development gives insights into breast disease 总被引:2,自引:0,他引:2
Aims : Studies of developing human breasts are essential for understanding the organogenesis as well as molecular pathogenesis of benign and malignant breast diseases. In this study we have examined the distribution of TGF-α, TGF-β1, tenascin-C and collagen type IV with the aim of starting to build a picture of the profile of molecules that may be involved in the development of the human breast.
Ten fetal breasts (16 to 23 weeks of gestation) and 45 infant breasts, ranging in age from newborn to 2 years, were used in this study. Paraffin sections from these samples were immunostained with antibodies for these proteins and for Ki67 to elucidate the level of proliferative activity in different stages of breast development. TGF-α immunoreactivity was observed both in the stromal and the epithelial cells within fetal and infant breasts up to 25 days. TGF-β1 immunoreactivity was localized in the extracellular matrix. Tenascin-C was found around the neck of the developing breast bud and in the extracellular matrix of the infant with peaks in the newborn at 6–12 weeks. The immunoreactivity for type IV collagen was more intense in the region of the breast bud neck in the fetal breasts and reduced around the tips of lobular and terminal-end buds within the infant breasts.
The distribution of the growth factors and extracellular matrix proteins within the developing human breast indicates that they play a significant role in different cellular compartments during morphogenesis and provides insights into breast disease. 相似文献
Methods and results
Ten fetal breasts (16 to 23 weeks of gestation) and 45 infant breasts, ranging in age from newborn to 2 years, were used in this study. Paraffin sections from these samples were immunostained with antibodies for these proteins and for Ki67 to elucidate the level of proliferative activity in different stages of breast development. TGF-α immunoreactivity was observed both in the stromal and the epithelial cells within fetal and infant breasts up to 25 days. TGF-β1 immunoreactivity was localized in the extracellular matrix. Tenascin-C was found around the neck of the developing breast bud and in the extracellular matrix of the infant with peaks in the newborn at 6–12 weeks. The immunoreactivity for type IV collagen was more intense in the region of the breast bud neck in the fetal breasts and reduced around the tips of lobular and terminal-end buds within the infant breasts.
Conclusions
The distribution of the growth factors and extracellular matrix proteins within the developing human breast indicates that they play a significant role in different cellular compartments during morphogenesis and provides insights into breast disease. 相似文献
956.
1988年至1991年对收治的发病5日以内的肾综合征出血热(HFRS)病人应用姬鼠型HFRSV陈株及家鼠型HFRSVR22株,免疫猪所制备的特异性双价纯化免疫血清F(ab)2(称F(ab)2血清),治疗HFRS病人65例作为研究组,以44例作为对照组。治疗结果表明:①球结膜水肿渗出减轻,24小时出血减轻;②白细胞病毒抗原消失迅速;③研究组出院平均早9.1天;④在洽疗后2、4日,对照组的特异性免疫荧光IgM抗体明显高于研究组的。⑤其他实验室检测指标都以研究组为优。提纯后的免疫血清F(ab)2无抗体-介导反应,无副作用及过敏反应。它含有特异性中和抗体及其他免疫因子,可中和清除体内的病毒抗原,减轻病毒血症及毛细血管壁的损伤,阻断病情发展,促进病情恢复。 相似文献
957.
Individual preparations of affinity purified anti-F(ab')2 antibodies and anti-Fc antibodies isolated from the sera of patients with rheumatoid arthritis (RA), were examined for reactivity with the Fab and Fc fragments of human IgG. Western blot assays demonstrated specific interaction of affinity-purified anti-Fab antibodies with both Fab and Fc molecules. Approximately one-half of the anti-Fab antibody preparations studied contained IgG antibodies reactive with Fab and Fc fragments in ELISA, suggesting the existence of naturally occurring epibody-like autoantibodies in these patients. Thirteen of 14 affinity-purified anti-Fc antibody preparations contained IgG cross-reactive with Fab molecules in ELISA. Double-adsorption assays on affinity columns demonstrated that a minimum of 14%, and possibly as much as 50%, of the IgG anti-Fab antibodies reacted with the Fc of IgG. Conversely, a minimum of 12%, and possibly as much as 70%, of the IgG anti-Fc antibodies reacted with IgG Fab molecules. Anti-Fab antibodies isolated from non-RA individuals also exhibited anti-Fc reactivity in ELISA, demonstrating the presence of these dual-reactive antibodies in other autoimmune and normal individuals. These studies establish the presence of naturally occurring IgG autoantibodies reactive with both the Fab and Fc fragments of human IgG. Their existence emphasizes the potential of anti-immunoglobulin antibodies to recognize a multiplicity of antigens, possibly including other members of the immunoglobulin supergene family. 相似文献
958.
959.
Pierre Marschall Ruicheng Wei Justine Segaud Wenjin Yao Pierre Hener Beatriz Falcon German Pierre Meyer Cecile Hugel Grace Ada Da Silva Reinhard Braun Daniel H. Kaplan Mei Li 《The Journal of allergy and clinical immunology》2021,147(5):1778-1794
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960.
Marrone O Salvaggio A Insalaco G Bonsignore MR Cimino M Gallina S Speciale R 《Journal of sleep research》1995,4(3):189-195
SUMMARY To verify whether upper airway surgery in obstructive sleep apnoea syndrome affects differently respiration in NREM and REM sleep, 22 patients were studied by polysomnography before and three months after surgical treatment. On the average, treatment improved respiration during both sleep states, but no significant interaction was found between sleep state and effect of surgical treatment. According to the response to treatment, three groups of patients were identified: the first group ( N = 6), with an improvement in apnoea-hypopnoea index (AHI), percentage of sleep time spent in apnoea and hypopnoea (time in AH) and mean oxyhaemoglobin saturation (SaO2 ) in both NREM and REM sleep; the second group ( N = 5), with an improvement in AHI only in NREM sleep, associated with improvement in mean SaO2 in both sleep states; the third group ( N = 11), without any improvement in AHI and time in AH, either associated ( N = 5) or not ( N = 6) with an improvement in mean SaO2 in both sleep states. An increase in the percentage of hypopnoeas out of the total AHI after treatment could partly account for the apparent discrepancy between AHI and mean SaO2 behaviour in the subjects of the second group, but not in the patients of the third group who improved their mean SaO2 . Mixed apnoeas occurred before surgery in six subjects; they remained numerous after surgery only in two subjects who did not show any SaO2 improvement. In conclusion, the degree of improvement in respiration after upper airway surgery was similar in every patient in NREM and REM sleep. 相似文献