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71.
This paper outlines the impact of granulocyte‐colony stimulating factor (G‐CSF) used as a single modality therapy in 17 patients with secondary autoimmune neutropenia (S‐AIN) who had been treated a multiple number of times previously. Fifteen of these patients had demonstrable antineutrophil antibodies and two had cellular S‐AIN with haemopoietic inhibitory T‐cells present in the marrow. Prior to treatment, all had had problems with infection. All patients responded within 7 days of commencement of treatment. Provided G‐CSF neutrophil counts were maintained above 1 × 109/l, no further infections occurred. This was achievable by using G‐CSF administered as infrequently as once every 8 days. Eight of the 17 patients remained on G‐CSF, although five switched to the glycosylated form because of side‐effects. None have developed osteoporosis despite 47.29 patient years of total experience with G‐CSF. In conclusion both glycosylated and nonglycosylated G‐CSF can be used effectively in treating AIN on a long‐term basis. 相似文献
72.
目的:分析T1期(肿瘤直径<2cm)原发性乳腺癌女性患者绝经前后在肿瘤大小、病理分类、淋巴结转移率和数目。方法:常规病理检验以及应用免疫组化、HE法分别测定绝经前乳腺癌患者和绝经后乳腺癌患者者的ER、PR。结果:两组患者在肿瘤大小上无明显差异,但绝经前乳腺癌患者浸润导管癌的百分比为 84. 7%,绝经后乳腺癌患者的浸润导管癌百分比为 62. 2%,经χ2 检验,P<0. 01。两组淋巴结转移率分别为 39. 3%和 25. 5%,经χ2 检验,P<0. 01。两组ER和PR阳性伴淋巴结转移的比例经χ2 检验,P<0. 05。结论:绝经前乳腺癌患者和绝经后乳腺癌患者在病理分类、淋巴结转移率及数目、ER、PR阳性伴淋巴结转移上有显著性差异。对于T1原发性乳腺癌患者不论有无淋巴结转移,均应行癌肿切除伴Ⅰ、Ⅱ级淋巴结清扫。 相似文献
73.
研究亚硫酸氢钠和氯化钠配伍使用的增敏性,建立了NaHSO3—NaCl—KIO3—KI四元无机体系测定碘盐中碘含量的新方法。测定碘的最佳条件:磷酸介质,pH 3~4,最大吸收波长479 nm,ε479=1.5×105L/(mol/cm),碘含量(以KIO3中I计)在0~2.24mg/L内符合比尔定律。用于测定食盐中碘的含量,回收率为99.49%~101.3%,结果满意。 相似文献
74.
C. Olgart Höglund J. Axén C. Kemi S. Jernelöv J. Grunewald C. Müller-Suur Y. Smith R. Grönneberg A. Eklund P. Stierna M. Lekander 《Clinical and experimental allergy》2006,36(8):982-992
BACKGROUND: Stress can aggravate the allergic inflammation, but determinants of disturbed immune regulation are largely unknown. OBJECTIVE: To determine systemic immunological, local inflammatory and functional airway responses to stress in healthy and atopic individuals. METHODS: Forty-one undergraduate students, 22 with allergy of whom 16 had asthma, and 19 healthy controls, were studied in a low-stress period and in association with a large exam. Subjects completed questionnaires on stress and health behaviours, underwent lung function tests, bronchial methacholine challenge, measurements of exhaled nitric oxide and urine cortisol. Blood cells were phenotyped, and cytokines from mononuclear blood cells were analysed. RESULTS: Perceived stress and anxiety increased in both groups during the exam period while cortisol increased only in the atopy group. Cytokine production decreased broadly in response to stress in both groups, which was paralleled by an increase in the proportion of regulatory T cells (CD4(+)CD45RO(+)CD25(bright)). Interestingly, atopic individuals, but not controls, reacted with a decreased T-helper type 1/T-helper type 2 (Th1/Th2) ratio and a decrease in natural killer (NK) cell numbers in response to stress. In control subjects only, exhaled nitric oxide decreased and forced expiratory volume in one second increased during stress. CONCLUSION: Atopic and non-atopic subjects shared some immune changes in response to stress, such as a dramatic decline in cytokines and an increase in the number of regulatory T cells in peripheral blood. However, other stress-induced immune changes were unique to atopic individuals, such as a skewed Th1/Th2 ratio and reduced NK cell numbers, indicating that some pathogenic mechanisms in atopics may be more strongly affected by stress than others. 相似文献
75.
茶水提取物和茶多酚抑制诱变的类型及其机制 总被引:3,自引:0,他引:3
目的 :研究茶水提取物和茶多酚的去突变特征和机制 ,鉴别茶和茶多酚去突变的量效关系和抑菌关系 ,了解去突变剂与直接诱变剂(1_NP)、间接(Trp_P_1)诱变剂的抗突变作用方式和抑制效果。 方法 :用细胞外抑制诱变试验和改进型两次活化的Ames试验方法。 结果 :茶水提取物和与其相关的儿茶素等都存在非抑菌性的去突变效果 ,其中表没食子儿茶素没食子酸酯(EGCG)和茶黄素(TF)的效果最好。抗突变试验结果表明 ,茶水提取物对Trp_P_1( +S9)有显著的抗突变性 ,与Trp_P_1的混合液在非代谢活性条件时无诱变性 ;茶水提取物对1_NP( -S9)也有抑制活性 ,但比对Trp_P_1的抑制活性低(P<0.01) ,与1_NP混合物经代谢活化后有诱变性 ,且与非代谢活化的抗突变结果呈较高的相关性(r= -0.9694)。 结论 :茶多酚能抑制间接诱变剂的前体形成 ,也有对直接诱变剂构成阻断剂的作用 ,但是在阻断具有强氧化性的诱变剂时可能形成不稳定的结合物或不安全的结构物。 相似文献
76.
Severe myoclonic epilepsy (SMEI) or Dravet syndrome is caused by mutations of the SCN1A gene that encodes voltage-gated sodium channel alpha-1 subunit. Recently, we generated and characterized a knock-in (KI) mice with an SCN1A nonsense mutation that appeared in three independent SMEI patients. The SCN1A-KI mice well reproduced the SMEI disease phenotypes. Both homozygous and heterozygous knock-in mice developed epileptic seizures within the first postnatal month. In heterozygous knock-in mice, trains of evoked action potentials in inhibitory neurons exhibited pronounced spike amplitude decrement late in the burst but not in pyramidal neurons. We further showed that in wild-type mice the Nav1.1 protein is expressed dominantly in axons and moderately in somata of parbalbumin (PV) – positive inhibitory interneurons. Our immunohistochemical observations of the Nav1.1 are clearly distinct to the previous studies, and our findings has corrected the view of the Nav1.1 protein distribution. The data indicate that Nav1.1 plays critical roles in the spike output from PV interneurons and further, that the specifically altered function of these inhibitory circuits may contribute to epileptic seizures in the mice. These information should contribute to the understanding of molecular pathomechanism of SMEI and to develop its effective therapies. 相似文献
77.
Kathleen Hawker 《Annals of Indian Academy of Neurology》2009,12(4):221-225
B cells have recently been identified as an integral component of the immune system; they play a part in autoimmunity through antigen presentation, antibody secretion, and complement activation. Animal models of multiple sclerosis (MS) suggest that myelin destruction is partly mediated through B cell activation (and plasmablasts). MS patients with evidence of B cell involvement, as compared to those without, tend to have a worse prognosis. Finally, the significant decrease in new gadolinium-enhancing lesions, new T2 lesions, and relapses in MS patients treated with rituximab (a monoclonal antibody against CD20 on B cells) leads us to the conclusion that B cells play an important role in MS and that immune modulation of these cells may ameliorate the disease. This article will explore the role of B cells in MS and the rationale for the development of B cell–targeted therapeutics. MS is an immune-mediated disease that affects over 2 million people worldwide and is the number one cause of disability in young patients. Most therapeutic targets have focused on T cells; however, recently, the focus has shifted to the role of B cells in the pathogenesis of MS and the potential of B cells as a therapeutic target. 相似文献
78.
Parastoo Jangouk Thomas Dehmel Gerd Meyer Zu Hörste Andreas Ludwig Helmar C. Lehmann Bernd C. Kieseier 《Glia》2009,57(16):1765-1774
The disintegrin and metalloproteinase 10 (ADAM10) is a membrane‐anchored metalloproteinase with both proteolytic and disintegrin characteristics. Here, we investigate the expression, regulation, and functional role of ADAM10 in axonal outgrowth and myelination of the peripheral nerve. Expression pattern analysis of 11 ADAM family members in co‐cultures of rat dorsal root ganglia (DRG) neurons and Schwann cells (SCs) demonstrated the most pronounced mRNA expression for ADAM10. In further studies, ADAM10 was found to be consistently upregulated in DRG‐SC co‐cultures before the induction of myelination. Neurons as well as SCs widely expressed ADAM10 at the protein level. In neurons, the expression of ADAM10 was exclusively limited to the axons before the induction of myelination. Inhibition of ADAM10 activity by the hydroxamate‐based inhibitors GI254023X and GW280264X resulted in a significant decrease in the mean axonal length. These data suggest that ADAM10 represents a prerequisite for myelination, although its activity is not required during the process of myelination itself as demonstrated by expression analysis of myelin protein zero (P0) and Sudan black staining. Hence, during the process of myelin formation, ADAM10 is highly upregulated and appears to be critically involved in axonal outgrowth that is a requirement for myelination in the peripheral nerve. © 2009 Wiley‐Liss, Inc. 相似文献
79.
80.
增生性瘢痕中血管内皮细胞生物学功能的研究 总被引:2,自引:1,他引:1
目的 探讨增生性瘢痕中血管内皮细胞的生物学功能及其与瘢痕形成的关系。方法 取人增生性瘢痕组织和正常皮肤组织,进行组织学观察。分离和纯化2种标本中的血管内皮细胞,应用酶联免疫吸附测定法分别检测单个血管内皮细胞中转化生长因子β1,(TGF-β1)、成纤维细胞生长因子2(FGF2)、血小板源性生长因子(PDGF)、内皮素1(ET-1)和血管内皮生长因子(VEGF)的水平。结果光学显微镜下可见正常皮肤微血管数目较少;增生性瘢痕微血管数目增多,血管狭长扭曲甚至闭塞。透射电镜可见增生性瘢痕中毛细血管管腔狭窄,有内皮细胞脱落。增生性瘢痕中血管内皮细胞分泌TGF-β1、PDGF、ET-1、VEGF、FGF2的水平分别为(60±8)、(30±4)、(0.12±0.03)、(52±5)、(18.1±1.2)μg/个细胞,明显低于正常皮肤(P〈0.05)。结论 增生性瘢痕中血管内皮细胞生物学功能减退,可能与瘢痕中胶原的大量产生和缺氧有关。 相似文献