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121.
Pavlos Brikas DVM PhD Bogdan F. Kania DVM Jean Fioramonti PhD DSc Dr. Lionel Bueno PhD DSc 《Digestive diseases and sciences》1993,38(6):1079-1086
The effects of duodenal distension on forestomach and abomasal motility were investigated in conscious sheep chronically fitted with intraparietal electrodes, a duodenal cannula, and an intracerebroventricular cannula. Duodenal distensions with a balloon inflated with 40 ml (DD40) of water reduced the frequency of forestomach and abomasal contractions by 45 and 32%, respectively, while distension with 80 ml (DD80) induced a total inhibition. Methysergide, a mixed 5HT1-5HT2 antagonist administered intravenously (200 g/kg) or intracerebroventricularly (20 g/kg) suppressed the DD40-induced inhibition and reduced that induced by DD80. Sprioxatrine, a selective 5HT1A antagonist, intravenously (100 g/kg) or intracerebroventricularly (10 g/kg), suppressed the DD40 and DD80-induced inhibition, which was also attenuated by the 5HT2 antagonist ritanserin given intravenously (200 g/kg) or intracerebroventricularly (20 g/kg). Granisetron, a 5HT3 antagonist, injected intravenously (150 g/kg), abolished the effects of DD40 and DD80 while it had no antagonistic action on DD40 and DD80 when given intracerebroventricularly (15 g/kg). It is concluded that in sheep, duodenal distension inhibits forestomach and abomasal motility through 5HT1A and 5HT2 receptors at the level of the central nervous system and 5HT3 receptors located peripherally.This work was presented in part at the First United European Gastroenterology Week, September 25–30, 1992, Athens, Greece. 相似文献
122.
BackgroundHepatitis C virus (HCV) status cannot be reliably predicted in anti-HCV positive/HCV-RNA negative individuals who may either have recovered spontaneously or have a false-positive test due to antibody cross-reaction. Investigating T lymphocyte responses in individuals with different HCV status may help understand the cellular immune mechanisms underlying spontaneous recovery, treatment response, and chronicity.ObjectiveWe aimed to determine whether anti-HCV positive, HCV-RNA negative individuals are truly spontaneous recoverers from acute HCV infection.Study designWe used enzyme-linked immunosorbent spot (ELISPOT) assay to compare HCV-specific lymphocyte response among anti-HCV positive/HCV-RNA negative individuals, patients with sustained virological response to interferon-γ/ribavirin treatment, and patients with chronic HCV infection.ResultsWe found that 83% of anti-HCV positive/HCV-RNA negative individuals without a past medical history of acute icteric hepatitis had an HCV-specific T lymphocyte response in peripheral blood. Lymphocyte responses in these individuals were similar in magnitude to treatment responders unlike patients with chronic HCV whose virus-directed immunity was significantly suppressed.ConclusionsDetection of HCV-specific T lymphocyte responses using ELISPOT is a feasible method to ascertain past asymptomatic acute HCV infection. 相似文献
123.
目的观测类风湿关节炎(RA)患者外周血CD4+T细胞表面程序性死亡因子1(PD-1,CD279)表达的变化、探讨PD-1在RA发生、发展中的作用。方法应用流式细胞术检测40例RA患者和20例健康体检者外周血CD4+T细胞表面PD-1的阳性率,对比分析RA患者病情活动组与稳定组间PD-1表达的差异,分析PD-1阳性率与C反应蛋白(CRP),红细胞沉降率(ESR),类风湿因子(RF)等临床指标的相关关系。结果病情活动期RA患者外周血CD4+T细胞PD-1阳性率为(32.90±12.15)%,明显高于健康体检者(22.32±6.04)%,差异有统计学意义(P<0.01);稳定期RA患者的PD-1阳性率为(27.49±6.79)%,与健康体检者的差异无统计学意义(P>0.05)。RA患者中,CD4+T细胞表面PD-1阳性率与RF呈正相关(r=0.525,P<0.01),与ESR呈正相关(r=0.328,P<0.05),与CRP无明显相关性(r=0.232,P>0.05)。结论病情活动期RA患者外周血CD4+T细胞表面PD-1表达增加,可能对疾病的发生、发展具有重要意义。 相似文献
124.
Damodaran Narayanan Olga K. Weinberg 《International journal of laboratory hematology》2020,42(1):3-15
Acute myeloid leukemia (AML) is a neoplasm of immature myeloid cells and is associated with a wide variety of clinical presentations, morphological features, immunophenotypes, and genetic findings. Recent advances in identification of cytogenetic abnormalities and mutations have provided novel insights into the pathogenesis of AML. Based on the above‐mentioned parameters, the World Health Organization (WHO) classified AML into 25 subtypes, including 2 provisional entities, which differ in prognosis and treatment. In addition, certain mutations are associated with germline predisposition and increase the risk of inherited AML, which warrants family screening. Therefore, precise diagnosis and classification of AML are the most important steps in patient management. Both these steps require incorporation of history, clinical presentation, and laboratory results with studies performed by a pathologist. Pathologist‐initiated studies include morphologic evaluation on the bone marrow aspirate and/or core biopsy, immunophenotyping by flow cytometry and/or immunohistochemistry, cytogenetic analysis by karyotyping and/or fluorescence in situ hybridization, and molecular testing using gene panels and/or next‐generation sequencing. A similar approach is employed during follow‐up of patients after beginning treatment. Here, we describe in detail the various aspects of the workup, including purpose, limitations, and practice guidelines for the different studies. The process of choosing appropriate materials for the different studies is also addressed. We also provide an algorithm for the workup and risk stratification of AML based on guidelines recommended by the WHO, College of American Pathologists, National Comprehensive Cancer Network, American Society of Clinical Oncology, European Society of Medical Oncology, and the European LeukemiaNet. 相似文献
125.
目的 探讨壮药透骨香抗类风湿关节炎作用的药物活性部位及作用机制。方法 体外培养法制备BALB/c小鼠脾淋巴细胞,经刀豆蛋白A(CoA)刺激作用后,以透骨香各药物部位进行干预, 细胞计数试剂盒-8(CCK-8)法检测细胞增殖情况,计算刺激指数;体外培养小鼠脾细胞,刀豆蛋白A刺激T淋巴细胞增殖,采用酶联免疫吸附实验(ELISA)法检测观察透骨香活性部位对细胞因子白细胞介素-2(IL-2)、白细胞介素-10(IL-10)含量的影响。结果 小鼠脾细胞经刀豆蛋白A刺激后,细胞计数试剂盒-8检测光密度(OD)值与刺激指数显著升高(P<0.05),透骨香正丁醇部位及水溶部位能明显降低光密度值及刺激指数,其中水溶部位(5 μg·mL-1)作用最强(P<0.05);刀豆蛋白A刺激脾淋巴细胞增殖后,细胞因子白细胞介素-2、白细胞介素-10分泌显著增强,透骨香水溶部位干预后能明显抑制白细胞介素-2分泌,提高白细胞介素-10含量(P<0.05)。结论 透骨香水溶部位对T淋巴细胞增殖具有较强抑制作用,是透骨香抗RA活性部位,其机制可能与调节细胞因子白细胞介素-2、白细胞介素-10分泌有关。 相似文献
126.
目的:探讨CC族趋化因子受体9( CCR9)在非小细胞肺癌( NSCLC )肿瘤免疫机制中的作用。方法采用流式细胞术检测42例NSCLC患者和30名健康人手术前后T细胞亚群以及外周血中CD4+T淋巴细胞表面CCR9的表达情况,计数各组细胞表达的百分率。免疫磁珠分选外周血CD4+T淋巴细胞,采用transwell实验检测并分析CCL25/CCR9对CD4+T淋巴细胞迁移的影响。结果 NSCLC患者外周血T淋巴细胞亚群均降低,术后外周血CD4+T淋巴细胞、CD4+/CD8+比值均明显高于术前[(49.11±8.32) vs (46.17±8.71),P=0.031和(1.66±0.09) vs (1.44±0.06),P=0.001];术前CD4+CCR9+T淋巴细胞的百分率低于术后[(3.33±1.11) vs (6.57±1.92),P<0.05]和健康对照组[(3.33±1.11) vs (11.06±1.37),P<0.05]。在CCL25诱导下,NSCLC患者外周血CD4+T淋巴细胞趋化指数(CI)为3.14,明显低于健康对照组的3.83( P<0.05)。经过anti-CCR9单抗处理后,CD4+T淋巴细胞的CI为0.62,与未经anti-CCR9 mAb处理者相比明显降低( P<0.05)。结论 NSCLC患者外周血T淋巴细胞调节机制紊乱,CL25/CCR9相互作用可介导外周血CD4+T淋巴细胞迁移,NSCLC患者外周血淋巴细胞中CCR9低表达,影响淋巴细胞迁移,可能与肿瘤逃避免疫监视的机制有关。手术可以逆转CD4+T淋巴细胞表面CCR9的表达变化, CCR9可能作为评价肺癌治疗后免疫重建的指标。 相似文献
127.
目的 了解肺结核患者临床特征与外周血流式细胞亚群[T淋巴细胞亚群及自然杀伤 (NK)细胞]的相关性。方法 连续性收集2019年1月1日至5月25日期间同济大学附属上海市肺科医院肺结核住院患者1000例的临床资料进行回顾性分析。将患者各临床特征数据与外周血流式细胞亚群的检测值采用Eviews 8.0软件分别建立多元线性逐步回归模型,以明确各临床特征与外周血流式细胞亚群的检测值之间的相关性。结果 (1)肺结核患者的肺部病灶范围及呼吸道标本抗酸染色涂片结果与CD3+T细胞表达有关:肺部病灶范围越大、呼吸道标本抗酸染色涂片阳性程度越高,CD3+ T细胞数量越低(回归系数分别为-0.255、-0.499, P值分别为0.021、0.027)。(2)患者的年龄、性别、结核分子生物学检测结果与CD4+ T细胞表达有关: 0~<20岁年龄段患者CD4+ T细胞数量低于其他年龄段患者(回归系数-4.710,P=0.031);男性CD4+ T细胞数量低于女性患者(回归系数-2.150, P=0.001);分子生物学检测阳性的患者CD4+ T细胞数量高于检测阴性的患者(回归系数1.433, P=0.030)。(3)初治患者CD8+ T细胞数量高于复治患者(回归系数1.247, P=0.029);呼吸道标本抗酸染色涂片阳性程度越高CD8+ T细胞数量越高(回归系数0.442, P=0.033)。(4)并发肺外结核者的NK细胞低于未并发肺外结核者(回归系数0.375, P=0.030)。结论 肺结核患者的肺部病灶累及范围、呼吸道标本抗酸染色阳性与外周血流式细胞亚群CD3+ T细胞具有相关性;年龄、性别、结核分子生物学检测结果与CD4+ T细胞具有相关性;是否初治、呼吸道标本抗酸染色阳性与CD8+ T细胞具有相关性;是否并发肺外结核与NK细胞表达水平具有相关性。 相似文献
128.
Mag. Dr. Johann Lehrner Gisela Pusswald Andreas Gleiss Eduard Auff Peter Dal-Bianco 《The Clinical neuropsychologist》2013,27(5):818-830
Olfactory dysfunction is a very early symptom of Alzheimer's disease (AD), and olfactory dysfunction has also been found in mild cognitive impairment (MCI). The goal of the present study was to compare odor identification ability and self-reported olfactory functioning in patients with different types of MCI. We included 104 elderly participants classified into two groups: patients with mild cognitive impairment (MCI) and elderly controls (EC). Based on their performance in neuropsychological testing the study population was divided into four groups of participants based on cognitive features: amnestic MCI single domain (11), amnestic MCI multiple domain (19), non-amnestic MCI single domain (21) and non-amnestic MCI multiple domain (13), respectively. The MCI patients were compared to 40 elderly controls (EC) controls with no cognitive deficit. Comparison for odor identification revealed a significant difference between amnestic MCI multiple domain patients and the EC group. No other group comparison was significant. Statistical analyses for self-reported olfactory functioning revealed no significant group differences between any subgroup of MCI patients and the control group. Correlational analyses indicated that odor identification ability was related to cognition whereas no relationship was found for self-reported olfactory functioning. The present study showed that amnestic MCI patients with additional deficits in other cognitive domains have a specific odor identification impairment. Together with cognitive testing, olfactory testing may more accurately help predict whether or not a patient with MCI will convert to AD in the near future. 相似文献
129.
《Expert Review of Clinical Immunology》2013,9(1):75-86
Allergic contact dermatitis, also referred to as contact hypersensitivity, is one the most frequent inflammatory skin diseases, and is characterized by redness, papule and vesicles, followed by scaling and dryness. Allergic contact dermatitis is elicited upon skin contact with nonprotein chemicals, haptens, and corresponds to a cutaneous delayed type hypersensitivity reaction, mediated by hapten-specific T-cells. During the sensitization phase, both CD4+ and CD8+ T-cell precursors are activated in the draining lymph nodes by presentation of haptenated peptides by skin dendritic cells. Subsequent hapten painting on a remote skin site induces the recruitment and activation of specific T-cells at the site of challenge. This leads to apoptosis of keratinocytes, recruitment of inflammatory cells and development of clinical symptoms. Experimental studies from the last 10 years have demonstrated that, in normal contact hypersensitivity responses to strong haptens, CD8+ type 1 T-cells are effector cells of contact hypersensitivity through cytotoxicity and interferon-γ production, while CD4+ T-cells are endowed with downregulatory functions. The latter may correspond to the recently described CD4+CD25+ regulatory T-cell population. However, in some instances, especially when there is a deficient CD8+ T-cell pool, CD4+ T-cells can be effector cells of contact hypersensitivity. Ongoing studies will have to confirm that the pathophysiology of human allergic contact dermatitis is similar to the mouse contact hypersensitivity and that the contact hypersensitivity response to common weak haptens, most frequently involved in human allergic contact dermatitis, is similar to that reported for strong haptens. 相似文献
130.