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991.
The present study was designed to investigate the relationship between intra-and inter-individual differences in arousal level and performance on both critical flicker fusion frequency and figural reversal tasks. Forty male undergraduate Ss were used. Electrical skin conductance was used as the indicant of arousal level. For the intra-individual comparisons white noise was used to increase the Ss’arousal levels. Significant inverted U-shaped relationships were found between both flicker fusion thresholds and rates of figural reversal and skin conductance between individuals. A significant curvilinear relationship was found between rates of figural reversal and level of conductance within individuals. No significant curvilinear relationship was found between flicker fusion thresholds and level of conductance within individuals. 相似文献
992.
D R Springall N B Ibrahim J Rode M S Sharpe S R Bloom J M Polak 《The Journal of pathology》1986,150(3):151-162
Several recent studies have confirmed the endocrine nature of small cell carcinoma of the lung. In extra-pulmonary sites, small cell 'undifferentiated' carcinomas have classical morphological features similar to their pulmonary counterpart. We therefore investigated, using immunocytochemistry, the possibility that the non-pulmonary neoplasms may also be endocrine in nature. Sections of 29 small cell carcinomas from oesophagus, stomach, larynx, colon and urinary bladder were immunostained using antisera to protein gene product 9.5 (PGP 9.5), neuron-specific enolase (NSE), cytokeratin, leucocyte common antigen and peptides including bombesin, the C-flanking peptide of human probombesin, adrenocorticotrophic hormone, neurotensin, calcitonin and pancreatic polypeptide. All the tumours showed immunoreactivity for at least one of the two general endocrine markers PGP 9.5 and NSE. Twenty-three of the 29 cases were immunoreactive for PGP 9.5, 27 for NSE. All were positive for cytokeratin and negative for leucocyte common antigen. Of the regulatory peptides, immunoreactivity was obtained with antisera to bombesin (one case), the C-flanking peptide of human pro-bombesin (14 cases), adrenocorticotrophic hormone (one case) and calcitonin (three cases). No PGP 9.5-, NSE- or peptide-like immunoreactivity was detected in 25 control tumours from similar sites, including lymphomas and poorly differentiated tumours. These results suggest that non-pulmonary small cell carcinoma has an endocrine character. 相似文献
993.
白细胞介素-8研究进展 总被引:14,自引:0,他引:14
白细胞介素-8(IL-8)在趋化性细胞因子家族中属于C-X-C亚家族,IL-8是一个多种细胞来源的趋化性细胞因子,而且不同类型的细胞对不同的诱导剂的反应也不相同,因为由不同的实验室从不同的来源得到该因子,所以对于IL-8的许多不同的描述术语,对于IL-8的生理生化特性,目前已基本清楚,对于IL-8基因表达的调节,现认为主要是在转录水平的调控,并且发现其基因5′-侧翼区的AP-1,NF-кB及NF-IL-6结合位点是调节IL-8启动子功能的主要顺式作用元件,IL-8基因的表达需要这些元件之间高度的协同以达到有效的转录,IL-8受体则是一个由59KDa和67KDa亚单位组成的二聚体糖蛋白,存在于多种类型的细胞上,甚至包括一些不表达IL-8的细胞,IL-8的生物学活性并不表现出种族的特异性,IL-8可激活中性粒细胞,对T-淋巴细胞有趋化性并能刺激嗜碱性粒细胞,内皮细胞IL-8基因的表达除了受化学因子的调节外还受力学因素的影响,流体切应力诱导内皮细胞表达IL-8,可能在急性炎症和动脉粥样硬化的发生,发展过程中具有重要作用。 相似文献
994.
Perceived failure is reported to have detrimental effects on subsequent performance in patients with major depressive disorder. We investigated the error-related negativity (ERN)/error negativity (Ne), an electrophysiological correlate of response monitoring, using a 64-channel EEG. Sixteen patients with DSM-IV major depressive disorder and 16 matched controls participated in an Eriksen flanker task with continuous performance feedback that signaled monetary reward. Compared to controls, patients with major depressive disorder showed a less negative ERN/Ne in error trials following error trials. This result might reflect impaired response monitoring processes in major depressive disorder resulting from an underactivity in a central reward pathway and/or a deficit in strategic reasoning. 相似文献
995.
The effects of chronic estrogen withdrawal and subsequent hormone replacement on the feeding and body weight of adult lean and genetically obese Zucker rats were investigated. Following confirmation of a delay in the vaginal canalization of the fatty rat, subgroups of each genotype received either ovariectomy or sham surgery (Experiment 1). One hundred days later all subjects were injected subcutaneously (SC) with 1.0 microgram of estradiol benzoate (EB) daily for 16 treatment days (Experiment 2A). A second series of daily 2.0 microgram EB injections was administered intraperitoneally (IP) for 1 week (Experiment 2B). The first experiment revealed that ovariectomy produced overeating and similar weight gains in both genotypes. In the second experiment, SC hormone treatment completely reversed ovarian obesity in lean animals but failed to alter the food intake or weight gain of fatty rats. IP administration of EB depressed the feeding of fatty and lean animals to a comparable degree but a reduction in weight gain was observed only in the lean rats. These findings are discussed in light of current theories of estrogenic modulation of energy balance. 相似文献
996.
采用时域有限差分(FDTD)法结合遗传算法(GA)优化设计了适用于浅表生物组织高频测量的宽带同轴贴片探头,并用该探头测量了人体背部1~7GHz频带内的反射特性。优化设计出的圆形同轴贴片探头具有轴对称特点,辐射近场在生物组织中透人深、反射系数的频率响应特性好。所获得的人体背部反射特性的测量结果将为背部浅表组织电特性的重建提供有利的依据。 相似文献
997.
Objective: We have evaluated the efficacy of the selective cyclo-oxygenase (COX)-2 inhibitor, rofecoxib, for the prevention of experimental colitis.Material and methods: To induce colitis BALB/c mice received 5% dextran sulphate sodium (DSS) in their drinking water continuously for 7 days. Rofecoxib (2.5–10 mg/kg body weight, p.o.) was administered throughout the treatment period with DSS. Colitis was quantified by a clinical damage score, colon length, weight loss, stool consistency and rectal bleeding. Inflammatory response was assessed by neutrophil infiltration, determined by histology and myeloperoxidase (MPO) activity. Interleukin (IL)-1, prostaglandin (PG)E2 and PGD2 levels in colon mucosa and the immunohistochemical expression of COX-1 and –2 were also studied.Results: The COX-2 inhibitor ameliorated severe colitis, reduced the degree of inflammation through reduction of neutrophil infiltration and IL-1 levels. PGE2, and PGD2 synthesis were significantly reduced in DSS-treated groups. Indeed, treatment with rofecoxib diminished the lost of COX-1 caused by DSS in the crypt epithelium whereas expression of COX-2 remained unaffected.Conclusions: Rofecoxib is protective in acute DSS – induced colitis, probably by reducing neutrophil infiltration, inhibiting up-regulation of IL-1 and returning to normal COX-1 expression in the inflamed colonic mucosa.Received 19 April 2004; returned for revision 17 June 2004; accepted by I. Ahnfelt-Rønne 23 November 2004 相似文献
998.
HLA-DR and DQ antigens and anticardiolipin antibodies in women with recurrent spontaneous abortions.
S Trabace M Nicotra S Cappellacci M Morellini C Muttinelli M Sbracia M A Di Prima C Masala 《American journal of reproductive immunology (New York, N.Y. : 1989)》1991,26(4):147-149
IgG anticardiolipin antibodies (ACL) have been shown to occur in a high proportion of women with repeated unexplained miscarriages. Forty-nine women with unexplained recurrent spontaneous abortions (RSA), previously assayed for the presence of ACL by an enzyme-linked immunoabsorbent assay, were typed for HLA-DR and DQ antigens by the classical microlymphocytotoxicity test. Twenty-five women were positive for ACL and 24 were negative. HLA-DR7 was found in 24.5% of 49 habitually aborting women vs. 28% of healthy controls; but the DR7 frequency was 40% in ACL positive patients vs. 8.3% in ACL negative patients (P = 0.011). These results show that in the Italian population an association between HLA-DR7 antigen and ACL is present in women with unexplained RSA, suggesting that HLA-DR genes might control the susceptibility to specific autoantibody production. 相似文献
999.
1000.
胃肠道癌患者血清中抗癌胚抗原(CEA)抗体的检测及意义 总被引:1,自引:0,他引:1
目的:探讨循环中抗癌胚抗原(CEA)特异性抗体的情况,评价CEA及抗体的联合检测在胃肠道癌诊断中的作用。方法:用放免法检测血清中 CEA含量,用酶联免疫吸附法(ELISA)检测抗 CEA IgG抗体,用竞争抑制法检测抗体的特异性。结果:胃肠道癌患者血清 CEA含量升高者(≥15 ng/ml)为 30.9%(21/68),抗 CEA IgG抗体阳性者为35.3%(24/68),CFA及抗 CEA抗体的联合检测可使阳性率提高到54.3%(37/68);胃肠道良性疾病患者(多发性息肉、溃疡、胰腺炎等)血清CEA升高者为3.3%(1/30),抗 CEA IgG抗体阳性者为 3.3%(1/30);健康对照组血清 CEA升高者为 0,抗 CEA IgG抗体阳性者为 2.5%(1/40)。结论:胃肠道癌患者血清中抗癌胚抗原(CEA)抗体的检出率较高,这些抗体可作为胃肠道癌的一种肿瘤标志物。 相似文献