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51.
H. XU A. SORURI R. K. H. GIESELER J. H. PETERS 《Scandinavian journal of immunology》1993,38(6):535-540
To investigate the differentiation and activation of monocytes, the combined effects of 1,25-dihydroxyvitamin D3 (D3) and IL-4 on human blood monocytes were examined with respect to expression of MHC class-II antigens, accessory activity, and phagocytic capacity. IL-4 was reported lo upregulate the expression of MHC class-II antigens and accessory activity of monocytes. The experiments described here demonstrate that D3 inhibits the expression of all three subtypes of MHC class-II antigens (HLA-DR, -DP and -DQ) as well as the accessory activity of monocytes. both in a dose- and time-dependent manner. However, D3 enhances the immunoglobulin- and complement-dependent phagocytosis by monocytes in a dose- and time-dependent manner. When monocytes are treated with both IL-4 and D3, the effects of D3 are reverted by IL-4. suggesting that IL-4 induces the development of monocytes into accessory cells, whereas D3 stimulates differentiation of monocytes into classical macrophages. These findings provide further evidence for the contention that, depending on defined stimuli, monocytes may develop either into accessory cells or into classical macrophages. 相似文献
52.
LJM, a 41-year-old schizophrenic Chinese man with bilateral anterior cingulate gyrus (Brodmann's area 24) lesions and also a small lesion in right amygdala after an operation, was compared with normal as well as brain-damaged and schizophrenic controls in identification of morphed facial expressions of six basic emotions. In repeated administrations of the test for recognition of facial emotions, over a 1- year period, LJM performed significantly worse for expressions of fear compared with the three groups of controls. Recognition of other emotions was not significantly different from that of the controls, except that his recognition of disgust during the first session (but not in two subsequent sessions) was worse than normal and brain-damaged controls but not worse than schizophrenic controls. The dissociation between recognition of fear and other emotions supported the view that the brain has separable networks for processing different emotions, and that the right amygdala as well as the anterior part of bilateral cingulate gyrus are possible substrates involved in the special network for perception of fear. The results from the various groups of Chinese subjects indicate that they perceive emotions in a categorical manner, and that the six basic emotions are likely to be cross-cultural universals. 相似文献
53.
Kai K Nasu K Nakamura S Fukuda J Nishida M Miyakawa I 《Molecular human reproduction》2002,8(2):176-180
Human endometrial stromal cells (ESC) can produce a variety of chemokines, especially after inflammatory stimulation. Interferon-gamma-inducible protein-10 (IP-10) is a potent chemoattractant for lymphocytes, and belongs to the family of non-ELR CXC chemokines. The expression of IP-10 in ESC after stimulation with interferon-gamma (IFN-gamma), interleukin-1 beta (IL-1 beta), tumour necrosis factor-alpha (TNF-alpha), or lipopolysaccharide (LPS) was evaluated using an enzyme-linked immunosorbent assay and Northern blot analysis. A small amount of IP-10 protein was detected in the culture media of unstimulated ESC. The expression of IP-10 mRNA was detected in ESC. IFN-gamma, IL-1 beta, TNF-alpha and LPS significantly stimulated the expression of IP-10 mRNA and protein in ESC. These results suggest that the production of IP-10 by ESC is regulated by inflammatory mediators. The modulation of IP-10 concentrations in the local environment may contribute to the normal and pathological processes of human reproduction by regulating leukocyte trafficking in the endometrium. 相似文献
54.
55.
Molyneux G Gibson FM Gordon-Smith EC Pilling AM Liu KC Rizzo S Sulsh S Turton JA 《International journal of experimental pathology》2005,86(6):415-430
Mitomycin (MMC), like many antineoplastic drugs, induces a predictable, dose-related, bone marrow depression in man and laboratory animals; this change is generally reversible. However, there is evidence that MMC may also cause a late-stage or residual bone marrow injury. The present study in female CD-1 mice investigated the haematological and bone marrow changes induced by MMC in a repeat dose study lasting 50 days. Control and MMC-treated mice were dosed intraperitoneally on eight occasions over 18 days with vehicle, or MMC at 2.5 mg/kg, autopsied (n = 6-12) at 1, 7, 14, 28, 42 and 50 days after the final dose and haematological changes investigated. Femoral nucleated bone marrow cell counts and levels of apoptosis were also evaluated and clonogenic assays carried out; serum levels of FLT3 ligand (FL) were assessed. At day 1 post-dosing, MMC induced significant reductions in RBC, Hb and haematocrit (HCT) values, and there were decreases in reticulocyte, platelet, and femoral nucleated cell counts (FNCC); neutrophil, lymphocyte and monocyte values were also significantly reduced. On days 7 and 14 post-dosing, all haematological parameters showed evidence of a return towards normal values, but at these times, and at day 28, values for RBC and FNCC remained significantly reduced in comparison with controls. At days 42 and 50 post-dosing, many haematological parameters in MMC-treated mice had returned to control levels; however, there remained evidence of late-stage effects on RBC, Hb and HCT values, and FNCC also continued to be significantly decreased. Results for granulocyte-macrophage colony-forming units and erythroid colonies showed a profound decrease immediately post-dosing, but a return to normal values was evident at day 50. Serum FL concentrations demonstrated very significant increases in the immediate post-dosing period, but a return to normal was seen at day 50 post-dosing; a relatively similar pattern was seen in the number of apoptotic femoral marrow nucleated cells. The histopathological examination of kidney tissues from MMC animals at day 42 and 50 post-dosing showed evidence of hydronephrosis with cortical glomerular/tubular atrophy and degeneration. It is therefore concluded that MMC administered on eight occasions over 18 days to female CD-1 mice at 2.5 mg/kg induced profound changes in haematological and bone marrow parameters in the immediate post-dosing period with a return to normal levels at day 50 post-dosing; however, there was evidence of mild but significant late-stage/residual effects on RBC and FNCC, and on cells of the erythroid lineage in the bone marrow. 相似文献
56.
双歧杆菌对早产儿食道pH值的影响及临床意义 总被引:2,自引:0,他引:2
目的为探讨双歧杆菌对早产儿食道pH值的影响,及其对早产儿易发生的消化道疾病的防治意义。方法我们采用便携式24hpH值自动记录仪,对61例早产儿进行了食道pH值的动态监测。结果口服双歧杆菌活菌制剂组的30例早产儿,食道pH值明显高于未服药的对照组,t=2.4093,P<0.05。总pH值<4的时间占总观察时间的百分比显著小于对照组。并且治疗组发生消化道疾患的人数也较对照组少。结论早产儿口服双歧杆菌活菌制剂可以减少胃食道反流等消化道疾病的发生。 相似文献
57.
58.
目的 分析持续性腹膜透析(PD)治疗老年慢性肾功能衰竭(CRF)患者的临床效果,探讨PD在老年CRF患者中的应用经验.方法 回顾性分析89例老年CRF患者接受PD(简称老年PD组)治疗后的临床表现和生化指标、主要并发症、存活率、死亡原因等,并与53例非老年PD组相比较.结果 老年PD组的原发疾病以糖尿病(37.08%)、原发性高血压(30.34%)为主,而非老年PD组则以肾小球肾炎(54.72%)为主.两组患者的1年与3年存活率差异无统计学意义,腹膜炎仍是两组患者退出PD的主要原因.老年组的病死率明显高于非老年组,感染与心脑血管病是两组患者的主要并发症和死亡原因.低钾血症在老年PD患者中非常普遍.结论 腹膜透析在老年CRF患者的治疗中有效,但长期存活仍受腹膜炎、心脑血管病并发症的影响,老年PD患者的低钾血症应引起足够的重视. 相似文献
59.
目的:分析肿瘤光动力治疗中的组织氧含量的变化规律,研究影响肿瘤光动力治疗效果的与氧相关的因素,探讨改进光动力治疗的途径。方法:建立肿瘤光动力治疗中氧含量的动态模型,并采用Crank—Nicolson离散方法解析该模型,在时间域和空间域上,分析光动力过程中肿瘤氧含量的动态变化过程,研究光照的光功率密度、肿瘤初始氧含量等因素对光动力疗效的影响,并比较间断光照和连续光照两种方式的不同疗效。结果:肿瘤氧含量随着治疗时间和离血管的距离呈衰减趋势,光动力反应只发生在血管附近的有限区域,且区域大小与初始氧含量密切相关.在较高的初始氧含量下,更大区域的氧含量因为处于阈值Cth以上,所以能发生光动力反应。当采用较低的光功率密度光照治疗时,肿瘤氧含量衰减比高功率密度下慢;当采用间断光照进行光动力治疗时,在治疗黑暗期肿瘤氧含量能得到回升.有利于光照期的治疗。结论:初始氧含量较高的情况下治疗效果更好;在较低的光功率密度下,光动力反应较难进行,但是有利于保护肿瘤供氧源的工作。在较低的初始氧含量下,间断光照方式的疗效要比连续光照要好。 相似文献
60.
Objective To study the distribution and quantity of CD44VCD24- cells in breast cancer tissue and the cell lines,and as well as its correlation with the expression of various breast cancer markers and molecular subtyping of breast carcinoma.Methods The expression of CD44 / CD24,estrogen receptor,progesterone receptor,HER2,human estrogen-induced protein PS2,bcl-2 and nm23 in 60 cases of invasive ductal carcinoma of breast were studied by either single or double immunohistochemical staining.The co-expression of CD44 and CD24 in 3 breast cancer cell lines (MCF-7,MDA-MB-468,and MDA-MB- 231) was also examined.Results The quantity and distribution of CD44 + /CD24- cells varied greatly and no specific patterns were identified.The percentage of CD44 + /CD24- in breast cancer was 65%.The amount of CD44+/CD24- cells did not correlate with the age of patients,lymph node metastasis,tumor size,molecular subtypes and expression of various breast cancer markers in breast carcinoma.The proportion of CD44+/CD24- cells in MCF-7,MDA-MB-468,and MDA-MB-231 cell lines was < 1%,5% and > 80% ,respectively.Conclusions CD44+ /CD24- cells are demonstrated in certain breast cancer tissues and cell lines.However,there is no relationship obtained between the quantity or the distribution of these cells and the molecular subtyping or the clinicopathologic parameters in breast cancer. 相似文献