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211.
P. Stark B. Shohat S. Kadosh M. Shaklai 《International journal of laboratory hematology》1999,21(3):187-192
The immunological dysfunction observed in B-chronic lymphocytic leukaemia (B-CLL) is often related to T-lymphocyte incompetence. The local xenogeneic graft-vs.-host reaction (XGVHR), an assay to evaluate T-lymphocyte function, was performed in 112 untreated B-CLL patients. The XGVHR results significantly correlated with clinical parameters: 37.1% of the patients in the stable phase (Rai stage 0–1–2) and only 13.3% of the patients in the progressive phase (Rai stage 3–4) had positive XGVHR results. Patients with negative results had a higher number and percentage of lymphocytes (25 247 vs. 17 071/μl and 75.9% vs. 65.6%, respectively), much lower T/B lymphocyte ratio (0.37 vs. 0.93), higher WBC count (30 977 vs. 23 458/μl), lower platelet count (158 068 vs. 181 684/μl) and lower levels of IgA and IgM (115.6 vs. 200.5 mg/dl and 80.4 vs. 124.3 mg/dl, respectively) compared to those with positive results. Among those with negative XGVHR results, a higher mortality rate was found in those who had infections compared with those who did not (73.7% vs. 9.1%). In conclusion, the XGVHR assay significantly correlates with important characteristics of B-CLL and may be useful in the clinical evaluation of B-CLL patients. 相似文献
212.
BACKGROUND: Solitary extramedullary plasmacytoma (SEP) is a rare tumour for which the standard treatment remains local radiotherapy (RT). We present a study of a multi-institutional experience, between 1980 and 1999, in an attempt to better understand the natural history of SEP and to identify possible prognostic factors. METHODS: The records at Radiation Oncology Victoria and Peter MacCallum Cancer Centre, Melbourne, were used for the identification of patients. The inclusion criteria were as follows: (i) histological confirmation of clonal plasma cells involving a single extramedullary site with or without lymph node involvement; (ii) no histological evidence of bone marrow involvement; (iii) no evidence of distant bone lesion on radiographic skeletal survey (bone erosions adjacent to the primary thought to be due to contiguous involvement were permitted) and (iv) no anaemia, hypercalcaemia or renal impairment due to plasma cell dyscrasia. RESULTS: A total of 16 patients was identified, with a median follow up of 66 months (range 12-211 months). The head and neck region accounted for the majority of presentations (88%). Among all patients, a serum mono-clonal paraprotein was found in three patients and bone erosion was identified in seven patients. All patients received local RT, although two patients also received elective nodal irradiation (ENI). The median RT dose was 45 Gy (range 40-50.4 Gy). Local control was achieved in all patients (100%), however, regional recurrence outside the RT fields occurred in 2/16. Multiple myeloma (MM) developed in five patients, all within 5 years. The predicted 10-year myeloma free survival is 75% and 10-year overall survival is 54%. CONCLUSION: RT can achieve excellent local control of SEP. The rate of conversion to MM is 31%. Moderate dose RT of at least 40 Gy using limited radiation fields is recommended, although ENI should be considered if toxicity is not increased. 相似文献
213.
目的 分析2015—2019年天津市眼科医院局部抗青光眼药品的使用情况及发展趋势。方法 对天津市眼科医院2015—2019年局部抗青光眼药品的销售金额、用药频度(DDDs)、日均费用(DDC)、排序比(B/A)等进行回顾性统计分析。结果 前列腺素衍生物类局部抗青光眼药品的销售金额远高于其他4类药品销售金额。拉坦前列素滴眼液(国产)、拉坦前列素滴眼液(进口)、曲伏前列素滴眼液、盐酸卡替洛尔滴眼液、酒石酸溴莫尼定滴眼液、布林佐胺滴眼液稳居本院用药金额前6位。盐酸卡替洛尔滴眼液DDD稳居第1位。除了2015—2016年盐酸卡替洛尔滴眼液的DDC值略有上升外,其他滴眼液的DDC值均维持不变或呈下降的趋势。盐酸卡替洛尔滴眼液的B/A最高。结论 本院局部抗青光眼药品使用基本合理,前列腺素衍生物类药物逐渐成为抗青光眼的一线用药。 相似文献
214.
Previous neuroimaging research has documented that patterns of intrinsic (resting state) functional connectivity (FC) among brain regions covary with individual measures of cognitive performance. Here, we examined the relation between intrinsic FC and a reaction time (RT) measure of performance, as a function of age group and task demands. We obtained filtered, event-related functional magnetic resonance imaging data, and RT measures of visual search performance, from 21 younger adults (19–29 years old) and 21 healthy, older adults (60–87 years old). Age-related decline occurred in the connectivity strength in multiple brain regions, consistent with previous findings. Among 8 pairs of regions, across somatomotor, orbitofrontal, and subcortical networks, increasing FC was associated with faster responding (lower RT). Relative to younger adults, older adults exhibited a lower strength of this RT-connectivity relation and greater disruption of this relation by a salient but irrelevant display item (color singleton distractor). Age-related differences in the covariation of intrinsic FC and cognitive performance vary as a function of task demands. 相似文献
215.
Justyna Jarczak Ewa M. KościuczukPaweł Lisowski Nina StrzałkowskaArtur Jóźwik Jarosław HorbańczukJózef Krzyżewski Lech ZwierzchowskiEmilia Bagnicka 《Human immunology》2013
The widespread use of antibiotics has contributed to a huge increase in the number of resistant bacteria. New classes of drugs are therefore being developed of which defensins are a potential source. Defensins are a group of antimicrobial peptides found in different living organisms, involved in the first line of defense in their innate immune response against pathogens. This review summarizes the results of studies of this family of human antimicrobial peptides (AMPs). There is a special emphasis on describing the entire group and individual peptides, history of their discovery, their functions and expression sites. The results of the recent studies on the use of the biologically active peptides in human medicine are also presented. The pharmaceutical potential of human defensins cannot be ignored, especially considering their strong antimicrobial activity and properties such as low molecular weight, reduced immunogenicity, broad activity spectrum and resistance to proteolysis, but there are still many challenges and questions regarding the possibilities of their practical application. 相似文献
216.
We investigated the perceptual time course of global/local processing using event-related potentials (ERPs). Participants discriminated the global or local level of hierarchical letters of different sizes and densities. Participants were faster to discriminate the local level of large/sparse letters and the global level of small/dense letters. This was mirrored in early ERP components: The N1/N2 had smaller peak amplitudes when participants made discriminations at the level that took precedence. Only global discriminations for large/sparse letters led to amplitude enhancement of the later P3 component, suggesting that additional attention-demanding processes are involved in discriminating the global level of these stimuli. Our findings suggest a dual-locus time course for global/local processing: (a) Level precedence occurs early in visual processing; (b) extra processing is required at a later stage, but only for global discriminations of large, sparse, stimuli, which may require additional attentional resources for active grouping. 相似文献
217.
局部场电位(LFP)反映了视觉刺激下大脑皮层局部区域神经元集群的响应.LFP响应特征的准确提取,对分析视觉信息的处理机制具有重要意义.本研究针对LFP的非平稳特性,采用具有自适应特征的希尔伯特黄变换,分解LFP固有模态分量,据此研究了大鼠Vl区对刺激光栅空间频率的响应调谐特性,并与多神经元锋电位(MUA)和小波分解提取的Gamma频带进行了对比.结果表明:LFP第二阶固有模态分量对刺激光栅空间频率的调谐特性最强,调谐指数的均值(0.795 1)高于MUA调谐指数(0.631 3)和小波分解调谐指数(0.6646),而且与MUA响应一致率达68.75%.所提出的方法在LFP响应频带特征提取上更有优势. 相似文献
218.
Attentional capture by salient distractors has been confirmed by the occurrence of an N2pc to the salient distractor. To clarify some failures to replicate this finding, we varied target predictability to induce different search modes. In the unpredictable target condition, the target shape varied randomly from trial to trial, favoring singleton detection mode. In the predictable target condition, the target shape remained the same in a block of trials, favoring feature search mode. With unpredictable targets, we observed an N2pc toward the salient color distractor, confirming attentional capture in singleton search mode. With predictable targets, there was no N2pc to the salient distractor, but a distractor positivity (Pd), suggesting distractor suppression. Also, differences emerged in the topographic segmentation of N2pc and Pd. Further, the amplitude of the N2pc toward the target was larger with predictable than with unpredictable targets. 相似文献
219.
《Journal of neurogenetics》2013,27(1):42-53
Abstract:Diverse neuronal cell types arise from the lateral neuroblast in the antennal lobe of Drosophila. The authors show that loss of Notch function from the entire lineage during development leads to an absence of local interneurons (LNs) with a concomitant increase in the number of projection neurons (PNs). The presence of the intracellular domain of Notch was observed within the nucleus of newly born neurons within the neuroblast lineage. This leads to the suggestion that Notch acts in a binary fate decision to determine formation of LNs and PNs, resulting in two distinct hemilineages from the single neuroblast. The observation of nuclear Notch in several neuroblast lineages leads us to speculate that this mechanism is widespread during the developing Drosophila brain. 相似文献
220.