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21.
Children with a specific learning disorder (SLD) are often characterized by marked intellectual strengths and weaknesses. In the last few years, research has focused on a common discrepancy between low working memory and processing speed on the one hand, and high verbal and visuoperceptual intelligence on the other. SLD profiles featuring a specific discrepancy between verbal and visuoperceptual abilities have been only marginally considered, however, and their systematic comparison vis-à-vis typically-developing (TD) populations has yet to be conducted. The present study examined a dataset of 1624 WISC-IV profiles of children with a diagnosis of SLD. It emerged that the proportion of children with a Verbal Comprehension Index (VCI) at least 1.5 SD (22 standardized points) lower than their scores on the Perceptual Reasoning Index (PRI) was larger than the proportion of SLD children with the opposite discrepant profile; it was also larger than the same proportion found among TD children. Comparing the two discrepant profiles revealed that the children also differed by type of learning difficulty, gender, and performance in the WISC-IV Symbol search task. Further examination suggested that children who were discrepant and also distinctly poor in visuoperceptual intelligence were particularly slow in general processing. 相似文献
22.
23.
《Vaccine》2020,38(51):8185-8193
BackgroundWhile administration of the measles-mumps-rubella (MMR-II®) vaccine has been effective at preventing rubella infection in the United States, the durability of humoral immunity to the rubella component of MMR vaccine has not been widely studied among older adolescents and adults.MethodsIn this longitudinal study, we sought to assess the durability of rubella virus (RV)-specific humoral immunity in a healthy population (n = 98) of adolescents and young adults at two timepoints: ~7 and ~17 years after two doses of MMR-II® vaccination. Levels of circulating antibodies specific to RV were measured by ELISA and an immune-colorimetric neutralization assay. RV-specific memory B cell responses were also measured by ELISpot.ResultsRubella-specific IgG antibody titers, neutralizing antibody titers, and memory B cell responses declined with increasing time since vaccination; however, these decreases were relatively moderate. Memory B cell responses exhibited a greater decline in men compared to women.ConclusionsCollectively, rubella-specific humoral immunity declines following vaccination, although subjects’ antibody titers remain well above the currently recognized threshold for protective immunity. Clinical correlates of protection based on neutralizing antibody titer and memory B cell ELISpot response should be defined. 相似文献
24.
目的观察健脾温肾软坚解毒方、康艾注射液联合低剂量化疗对老年脾肾两虚型晚期非小细胞肺癌患者瘤灶、免疫功能及无进展生存期的影响。方法将80例老年脾肾两虚型晚期非小细胞肺癌患者随机分为治疗组和对照组,每组40例。对照组予常规剂量化疗,治疗组予健脾温肾软坚解毒方、康艾注射液联合低剂量化疗。化疗2个周期后,观察两组患者瘤灶、免疫功能的变化情况,随访患者的无进展生存期。结果①试验期间,对照组脱落2例,试验组无脱落,最终完成试验者78例,其中治疗组40例,对照组38例。②两组实体瘤疗效比较,差异无统计学意义(P0.05)。③化疗1个周期与化疗前组内比较,两组血清NK、CD3~+、CD4~+、CD8~+水平差异无统计学意义(P0.05);化疗2个周期与化疗前组内比较,治疗组血清CD8~+水平升高(P0.05),对照组血清NK、CD3~+、CD4~+水平降低(P0.05)。化疗1个周期后组间比较,治疗组血清CD3~+、CD4~+水平高于对照组(P0.05);化疗2个周期后组间比较,治疗组血清NK、CD3~+、CD4~+水平高于对照组(P0.05)。④两组患者中位无进展生存时间均为4.5个月,差异无统计学意义(P0.05)。结论健脾温肾软坚解毒方、康艾注射液联合低剂量化疗能有效控制老年肺肾两虚型晚期非小细胞肺癌患者的瘤灶变化,并有利于稳定血清NK、CD3~+和CD4~+水平,保护患者的免疫功能。 相似文献
25.
S. Xing X. Zhang J. H. Liu X. Huang P. Zhou 《Clinical and experimental immunology》2019,195(1):121-131
Recent experimental strategies to reduce graft-versus-host disease (GVHD) have focused largely on modifying innate immunity. Toll-like receptor (TLR)-driven myeloid differentiation primary response 88 (MyD88)-dependent signalling pathways that initiate adaptive immune function are also critical for the pathogenesis of GVHD. This study aimed to delineate the role of host MyD88 in the development of acute GVHD following fully major histocompatibility complex-mismatched allogeneic bone marrow transplantation (BMT). When myeloablated BALB/c MyD88 knock-out recipients were transplanted with C57BL/6 (B6) donor cells, they developed significantly more severe GVHD than wild-type (WT) BALB/c hosts. The increased morbidity and mortality in MyD88–/– mice correlated with increased serum levels of lipopolysaccharide and elevated inflammatory cytokines in GVHD target organs. Additionally, MyD88 deficiency in BMT recipients led to increased donor T cell expansion and more donor CD11c+ cell intestinal infiltration with apoptotic cells but reduced proliferation of intestinal epithelial cells compared with that in WT BMT recipients. Decreased expression of tight junction mRNA in epithelial cells of MyD88–/– mice suggested that MyD88 contributes to intestinal integrity. Cox-2 expression in the GVHD-targeted organs of WT mice is increased upon GVHD induction, but this enhanced expression was obviously inhibited by MyD88 deficiency. The present findings demonstrate an unexpected role for host MyD88 in preventing GVHD after allogeneic BMT. 相似文献
26.
《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity. 相似文献
27.
By substituting the saturated vapour phase tension of the pure normal hydrocarbons described by the Clausius-Clapeyron law into the accepted expression of the specific retention volume (Vg,T), a theoretically coherent and relatively simple mathematical evidence of the elution behaviour of the homologous members has been deduced. It gives exponential retention time dependence on carbon number for isothermal, and nearly equidistant (i.e., approximately linear retention-time dependence on carbon number) elution for linear temperature programmed gas chromatographic runs. The final equations are in close correlation with the experimental results. Special emphasis is placed on the fact that a good approximation—not strict physical laws—have been found. 相似文献
28.
Tetsuro Sano Munetaka Masuda Shigeki Morita Hisataka Yasui 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(4):149-154
OBJECTIVE: It is well documented that cardiopulmonary bypass (CPB) severely impairs cellular immunity. The objective of this study was to investigate the effect of prostaglandin E1 (PGE1) on cellular immunity after CPB. METHODS: Patients who underwent elective cardiac surgery were randomly divided into the PGE1 group (n=12) and the control group (n=12). In the PGE1 group, PGE1 was administered at 20 ng/kg/min from just after the induction of anesthesia to the end of surgery. Peripheral blood mononuclear cells (PBMCs) were taken before anesthesia and on postoperative days 1, 3 and 7 (POD 1, POD 3 and POD 7). Proliferation responses of T cells to phytohemagglutinin (PHA) and pure protein derivative (PPD) antigen were measured as indicators of cellular immunity. RESULTS: PGE1 significantly attenuated the impairment of both PHA and PPD response after cardiac surgery on POD 1 (PHA response, 30 +/- 21% vs. 53 +/- 32%, control vs. PGE, p=0.048; PPD response, 18 +/- 21% vs. 39 +/- 27%, control vs. PGE, p=0.046). The reduced glutathione content of PBMCs in the control group was significantly decreased on POD 1. CONCLUSION: PGE1 attenuated the impairment of cellular immunity after cardiac surgery with CPB by reducing oxidative stress on PBMCs. 相似文献
29.
马尔尼菲青霉病不同类型病变中免疫反应观察 总被引:2,自引:0,他引:2
选用2组病变类型不同的6例马尔尼菲青霉病人病变组织,采用免疫组化PAP法,观察病变组织中l8淋巴细胞、巨噬细胞、IgG、IgM、乙等免疫指标。结果发现马尔尼菲青霉病的病变类型取决于机体的免疫功能状态,人体抗马尔尼菲青霉免疫以细胞免疫为主,组织中T细胞的存在对于杀灭真菌、局限病变具有积极意义;体液免疫特别是特异性抗体的出现除具有促进细胞免疫功能外,可能也是脓肿成因之一。 相似文献
30.
人参根总皂甙对热应激小鼠免疫功能保护作用的机制初探 总被引:1,自引:0,他引:1
小鼠在45℃高温环境15 min.末梢血T淋巴细胞百分数和淋巴细胞占白细胞百分数均下降.血清皮质酮升高。应激前15 min lP人参根总皂甙(GRS)50、100 mg·kg~(-1)可防止末梢血T淋巴细胞百分数的降低,但不能抑制血清皮质酮的升高。GRS50mg·kg~(-1)ip可防止末梢血中淋巴细胞占白细胞百分数的降低。GRS50 mg·kg~(-1)、利血平0.5 mg·kg~(-1)或水杨酸毒扁豆碱0.3 mg·kg~(-1)ip均可消除热应激对小鼠迟发超敏反应的抑制作用。 相似文献