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991.
Primary non-Hodgkin's lymphoma of the intestine: a morphological, immunohistochemical and clinical study of 31 Chinese cases 总被引:5,自引:0,他引:5
Thirty-one cases of primary non-Hodgkin's lymphoma of the intestine were investigated. Twenty-one were of B-cell and 10 of T-cell origin. The B-cell lymphomas comprised two cases of low-grade B-cell lymphoma of mucosaassociated lymphoid tissue (MALT), one of centroblastic/centrocytic type, three of high-grade B-cell lymphoma coexisting with a low-grade B-cell lymphoma of MALT, nine of centroblastic, three of immunoblastic and three of Burkitt type. Of the T-cell lymphomas, eight were of pleomorphic medium-to large-sized cell type and two of large cell anaplastic type. All the B-cell lymphomas expressed CD20 (L26) and/or Ki-B5; in six there was monotypic immunoglobulin light chain restriction. Membrane positivity for CD45RO (UCHL1) was observed in the 10 cases of T-cell lymphoma, but the tumour cells did not express monocyte-macrophage markers. Clinically, the patients with T-cell lymphomas were usually young males with constitutional symptoms and their prognosis was significantly worse than those of patients with intestinal B-cell lymphoma. 相似文献
992.
闭合性颅脑外伤患者事件相关电位的研究 总被引:1,自引:0,他引:1
目的:研究ERP对闭合性颅脑外伤患者脑认知功能变化的评估作用。方法:应用Medicid-03E脑诱发电位仪测定168例闭合性颅脑外伤患者的视觉(图像)、听觉诱发的P3波之潜伏期和波幅,并与正常对照组作比较,54例患者进行复测比较。结果:病人组P3潜伏期较正常对照组明显延长(P<0.001),波幅降低;P3波潜伏期、波幅与患者病情严重程度相关;有原发昏迷者改变尤为突出;随着病情的好转,P3潜伏期逐渐缩短,波幅亦逐渐增高。结论:ERP是测定闭合性颅脑外伤患者脑认知功能变化的一项客观指标。 相似文献
993.
目的 探讨超声彩色脉搏波(UFPWV)技术在定量评价2型糖尿病患者颈动脉血管管壁弹性变化中的应用价值。方法 回顾性研究。纳入2018年7月-2019年3月蚌埠医学院第一附属医院收治的97例2型糖尿病患者为观察组,其中男47例、女50例,年龄20~74(46.6±9.3)岁;根据颈动脉内中膜厚度(IMT)将观察组分为颈动脉粥样斑块组(A组)、颈动脉内中膜增厚组(B组)和颈动脉内中膜正常组(C组),依据下肢动脉有无斑块将C组分为下肢动脉斑块组(C1组)、下肢动脉无斑块组(C2组)。选取2017年12月-2018年12月在蚌埠医学院第一附属医院体检中心血糖及颈动脉IMT正常的健康体检者64人为对照组,其中男25人、女39人,年龄20~74(44.3±12.0)岁。运用UFPWV采集脉搏波速度 (PWV),计算颈动脉收缩早期PWV(PWV-BS)及收缩晚期PWV(PWV-ES),分析各项参数组间的差异。结果 观察组中,A组颈动脉PWV-BS、PWV-ES分别为(9.51±1.25)m/s、(10.79±1.64)m/s,B组分别为(8.47±0.91)m/s、(9.81±1.05)m/s,C组分别为(7.97±0.77)m/s、(9.07±0.74)m/s,对照组颈动脉PWV-BS、PWV-ES分别为(6.10±1.00)m/s、(7.40±1.20)m/s,A组、B组、C组及对照组间颈动脉PWV-BS、PWV-ES测量值依次降低,差异均有统计学意义(P值均<0.05)。C组中,C1组颈动脉PWV-BS、PWV-ES分别为(7.83±0.85)m/s、(8.82±0.59)m/s,C2组分别为(8.14±0.64)m/s、(9.34±0.79)m/s, C1组PWV-ES显著高于C2组,差异有统计学意义(t=3.402,P<0.01),而两组间PWV-BS的差异无统计学意义(P>0.05)。结论 UFPWV技术可定量评价2型糖尿病患者颈动脉弹性变化,并可通过PWV-ES的改变评估颈动脉形态学正常的患者动脉粥样硬化的进展程度,对临床诊疗具有一定意义。 相似文献
994.
Tzelepi A Yang Q Kapoula Z 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,164(1):67-77
In this study, we investigated the effect of transcranial magnetic stimulation (TMS) over the right posterior parietal cortex (PPC) on the latency of two different types of visually-guided vertical saccades: reflexive saccades triggered by the sudden onset of a target, and saccades towards target locations known in advance. For this reason, we used two oculomotor tasks: a gap and a delay task, respectively. Nine normal subjects performed vertical saccades at ±7.5 and ±15°. TMS was applied at 80 and 100 ms after target onset in the gap task, and after fixation offset in the delay task. Without TMS, we confirmed a latency asymmetry in the gap task favouring upward saccades at the lower eccentricity (7.5°), and a latency symmetry in the delay task. TMS increased the latencies of all saccades in the delay task, when delivered at 100 ms. This effect was mostly pronounced for downward saccades at 7.5°. As a result, saccade latencies showed an asymmetry in this condition, similar to the one observed in the gap task without TMS. The gap task with TMS resulted in a variable latency distribution and no significant overall effect on saccade latency. Our results indicate that the right PPC is involved in the initiation of vertical saccades in the delay task, and that this involvement appears to be enhanced for downward saccades. A conclusion for the involvement of this area in the gap task could not be drawn from this study. 相似文献
995.
Rapid, accurate genotyping of the common -alpha(4.2) thalassaemia deletion based on the use of denaturing HPLC
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AIMS: To develop an alternative assay for specific genotyping of the -alpha(4.2) thalassaemia deletion based on the DNA sequence features surrounding the breakpoint. METHODS: The 5' and 3' ends of the breakpoint regions of the -alpha(4.2) allele and the normal homologous segments were sequenced in Chinese individuals. A sequence haplotype composed of four single nucleotide variations within the X2/X1 box of the -alpha(4.2) breakpoint region was found in all of the 10 Chinese -alpha(4.2) thalassaemia alleles studied. Based on these findings, a novel polymerase chain reaction (PCR)/denaturing high performance liquid chromatography (DHPLC) assay was developed for rapid genotyping of the -alpha(4.2) allele instead of traditional Southern blotting or Gap-PCR. This method involves amplification of the alpha globin target sequence encompassing these four polymorphic sites, followed by a partially denaturing HPLC analysis using the transgenomic WAVE DNA fragment analysis system. RESULTS: The three major genotypes (-alpha4.2/alphaalpha, -alpha(4.2)/--SEA, and alphaalpha/alphaalpha) could be distinguished through the characteristic chromatograms generated by the WAVE system. The accuracy of this technique was evaluated blindly, and the results were 100% (40 of 40) concordant with the genotypes previously characterised by Southern blotting or Gap-PCR. CONCLUSIONS: This study validates the PCR/DHPLC approach as a simple, rapid, highly accurate, and cost effective method, potentially adaptable for use in epidemiological surveys, genetic screening, and diagnosis of silent alpha+ thalassaemia and Hb H disease. 相似文献
996.
Ketamine inhibits LPS-induced calcium elevation and NF-kappa B activation in monocytes 总被引:10,自引:0,他引:10
Objective:To investigate whether ketamine could inhibit lipopolysaccharide (LPS)-induced intracellular calcium elevation and NF-kappa B activation in monocytes.
Materials and methods:Isolated rat monocytes were challenged with 10 g/ml LPS with or without the presence of various concentrations of ketamine (10, 100, 1000 M). Intracellular calcium was monitored by laser confocal microscopy. NF-kappa B activity of the nuclear extracts of monocytes was analyzed by electrophoretic mobility shift assay (EMSA).
Results:LPS provoked a significant calcium elevation and enhanced NF-kappa B activity in monocytes. Ketamine above concentration of 100 M inhibited endotoxin-induced intracellular calcium elevation and NF-kappa B activity. Ketamine itself had no effect on either of them.
Conclusions:These findings suggest that ketamine could suppress NF-kappa B in monocytes exposed to endotoxin, and this anti-inflammatory effect might act through attenuating intracellular calcium elevation.Received 31 October 2003; returned for revision 18 December 2003; accepted by I. Ahnfelt-Rønne 26 Januaryy 2004 相似文献
997.
胰腺黏液性囊性肿瘤临床病理分析 总被引:2,自引:0,他引:2
目的;探讨胰腺黏液性囊性肿瘤(MCN)的临床病理学特点。方法:6例MCN均行B超或CT检查。除1例外,均作了手术切除治疗。对6例(MCN)作常规HE及免疫组织化学染色观察。结果:6例MCN中,女性4例,男性2例,平均年龄47岁,均位于胰腺体尾部。黏液性囊腺瘤(MCA)3例,囊壁内衬高柱状黏液上皮,上皮周围可见卵巢样间质组织;黏液性囊腺癌(MCC)3例,黏液上皮 有不典型增生,均有囊壁或胰腺组织的浸润,1例上皮周围可见卵巢样间质。CEA和CK 7在上皮中均阳性,c-erbB-2均阴性,间质SMA均阳性。结论:胰腺MCN是好发于中年女性的少见肿瘤,绝大多数发生于胰腺体尾部。MCA内衬高柱状上皮,上皮外来卵巢样间质包绕;MCC上皮细胞有不典型增生, 浸润性生长。MCN手术切除率高。 相似文献
998.
Introduction of new clones of penicillin-nonsusceptible Streptococcus pneumoniae in Hong Kong
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Analysis of penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) isolates in Hong Kong by use of a combination of antibiogram typing, serotyping, multilocus sequence typing, and pulsed-field gel electrophoresis indicated that the dissemination of PNSP was the result of the spread of international clones: variants of the Spain(23F)-1 or Spain(6B)-2 clones were the predominant PNSP isolates from 1994 to 1997 and remained so, but Taiwan(19F)-14 and Taiwan serotype 6B clones were disseminated in Hong Kong in 1999 and 2000. Concomitant changes in antibiotic susceptibility profiles, with the rate of susceptibility to chloramphenicol rising from 10% in the period from 1994 to 1997 to 31% (P < 0.001) in 1999 and 2000, were noted to accompany the shift of clones. 相似文献
999.
BACKGROUND: Haptoglobin polymorphism is associated with the prevalence of infections, autoimmune diseases, cardiovascular diseases, and other disorders. Congenital haptoglobin deficiency is associated with anaphylactic transfusion reactions in anhaptoglobinaemic patients with antihaptoglobin antibody. AIMS: To investigate haptoglobin genotypic distribution (including the Hp(0) allele) and associated serum haptoglobin concentrations in Koreans. METHODS: Five hundred and nine healthy Korean adults were randomly selected. Two methods were used: haptoglobin genotyping based on a polymerase chain reaction (PCR) system that exploited the structural difference of the Hp(1) and Hp(2 )alleles, and another PCR method that detected haptoglobin gene deletion by amplification of the junctional region of the Hp(0) allele. Serum haptoglobin concentrations were measured by nephelometry. RESULTS: The haptoglobin genotypes of 509 subjects were as follows: Hp(1)Hp(1), 7.1%; Hp(2)Hp(1), 37.7%; Hp(2)Hp(2), 49.3%; Hp(0)Hp(1), 2.2%; Hp(0)Hp(2), 3.5%; Hp(0)Hp(0), 0.2%. The gene frequency of Hp(0) in Koreans was calculated to be 0.031. Significant differences were seen among the concentrations of each haptoglobin genotype (Kruskal-Wallis test). Hp(0)Hp(2), but not Hp(0)Hp(1), was associated with hypohaptoglobinaemia. CONCLUSIONS: PCR methods for differentiating between haptoglobin genotypes, including the Hp(0) allele, may be useful in a broad spectrum of basic studies and clinical examinations. 相似文献
1000.
Physostigmine is an anti-cholinesterase used for the pretreatment of a poisoning caused by highly toxic organophosphorus neurotoxins. The aim of this study is to design a polymeric microparticle system for sustained release of physostigmine. In this paper, we have attempted to encapsulate physostigmine in microparticles made from poly(D,L-lactide-co-glycolide) (PLGA) with various contents of glycolide and poly(D,L-lactide) (PLA) using spray-drying and single emulsion techniques. It was found that during the single emulsion process, most of the physostigmine molecules were lost in the external aqueous phase. However, more than 90% encapsulation efficiency of physostigmine was obtained using the spray-drying technique. SEM micrographs revealed that spherical microparticles containing physostigmine with a smooth surface were yielded with PLA, PLGA 50:50, RG 502 (PLGA 50:50 with a lower molecular weight) and PLGA 65:35 but PLGA 85:15, PLGA 75:25 and PLGA 50:50 with a high concentration produced microparticles with irregular shapes. An increased inlet temperature yielded a higher physostigmine release rate from the PLA microparticles. Physostigmine release from the microparticles showed a biphasic pattern, characterized by an initial burst release followed by a sustained release for PLGA 65:35, PLGA 50:50 and RG 502 or a non-detectable release for PLGA 85:15, PLGA 75:25 and PLA. A sustained-release of physostigmine with a low initial burst over 1 week was achieved from RG 502 microparticles, which would be used as an injectable dosage form in our further animal studies. 相似文献