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51.
Lehner T Bergmeier LA Wang Y Tao L Sing M Spallek R van der Zee R 《European journal of immunology》2000,30(2):594-603
Heat shock proteins (HSP) are widely distributed and highly immunogenic molecules. A novel property reported here is that stimulation with HSP70 of CD8-enriched T cells derived from naive non-human primates caused a dose-dependent increase in concentrations of the beta-chemokines RANTES, macrophage inflammatory protein (MIP)-1alpha or MIP-1beta. However, the concentrations of these beta-chemokines were greatly increased when the CD8 T cells derived from HSP70-immunized non-human primates were stimulated with HSP70. HSP linked to peptides or proteins combined generation of beta-chemokines with an adjuvant function by enhancing specific T cell proliferative responses and IgG and IgA antibodies. The beta-chemokine and adjuvant functions were also elicited by topical mucosal administration of HSP linked to an antigen. We postulate that microbial HSP can stimulate beta-chemokine production which may be responsible for innate adjuvanticity, as was found in cells eluted from normal rectal mucosal tissue, and constitutes a significant component of the mucosal-associated lymphoid system. Furthermore, stimulation of innate immunity may drive adaptive immunity and account for the protective effects of HSP against tumors and viruses. 相似文献
52.
Projections from the hypothalamus and its adjacent areas to the posterior pituitary in the rat 总被引:3,自引:0,他引:3
Cholera toxin conjugated horseradish peroxidase was injected into the posterior pituitary and its afferents traced in 21 albino rats. The neuronal processes as well as the perikarya were elaborately displayed. The principal and retrochiasmatic supraoptic nuclei and the magnocellular paraventricular subnuclei were densely labelled. The accessory cell groups or nuclei labelled included: the medial preoptic and anterior hypothalamic areas, the anterior and posterior fornical nuclei, the lateral hypothalamic area, the nucleus circularis and nucleus of the forebrain bundle and hitherto unknown or not fully appreciated retrochiasmatic area, the dorsal accessory groups in an area between the stria medullaris and fornix, on the one hand, and the stria terminalis and internal capsule, on the other, and a well developed subependymalperiventricular zone. The medial preoptic nucleus, subfornical organ and organ vasculosum laminae terminalis were also weakly stained. Dendrites of the magnocellular paraventricular nucleus have been said by some to be largely confined to the subnuclei in which they lie. Immunohistochemical studies have proved that they extended beyond their nuclear confinement. The present study has found much wider extension of their dendritic fields. In fact, dendrites of the magnocellular neurosecretory cells in general were long and had a certain degree of directional bias. Several sites projecting to the posterior pituitary were closely related to the cerebrospinal fluid. Namely, the subependymal neuronal plexuses along the third ventricle and beneath the interventricular foramen, and the subpial dendritic plexuses of the supraoptic and retrochiasmatic supraoptic nuclei. Neurons were seen to squeeze in-between the ependymal cells, bringing themselves very close to the cerebrospinal fluid. No direct cerebrospinal fluid-contacting elements, either cell bodies or processes, however, could be ascertained. It is proposed that these plexuses may monitor changes in the cerebrospinal fluid. Besides the principal neurohypophysial tract the posterior pituitary was found in the present study to receive its afferents via two accessory fasciculi, one coursing in the medial forebrain bundle and the other running along the lateral wall of the infundibular recess subependymally. 相似文献
53.
From 1976 to June 1982, 237 patients with clinical suspicion of hepatic malignant disease underwent guided percutaneous fine-needle aspiration biopsy of the liver. Of these, 12 were diagnosed cytologically as "hepatocellular carcinoma" and this diagnosis was confirmed in the follow-up of all cases. On the basis of the cytomorphologic features observed in the aspirates, the tumor was subclassified into three types; well differentiated, pleomorphic large cell; and poorly differentiated. The various cytologic appearances of different types of hepatocellular carcinoma are presented and illustrated. Cytomorphologically, these three types of hepatocellular carcinoma were distinctly different and their cytomorphologic features were also sufficiently distinctive from those of secondary hepatic cancer to be diagnostic. Guided percutaneous fine-needle aspiration biopsy of the liver appears to be a definitive minimally invasive means of establishing the diagnosis of hepatocellular carcinoma, and promises to be a valuable diagnostic procedure for potentially resectable localized hepatocellular carcinoma. 相似文献
54.
Ken Wei Tan Sharon Esi Duoduwa Quaye Joel Ruihan Koo Jue Tao Lim Alex R. Cook Borame L. Dickens 《Nutrients》2021,13(4)
Globally, many countries are facing an increasing burden of chronic disease due to ageing populations, of which cardiovascular disease forms a large proportion. Excess dietary sodium contributes to cardiovascular disease risk and requires intervention at a population level. This study aimed to quantify the impact of several salt reduction initiatives on population health over a 30-year horizon using GeoDEMOS, a population model from Singapore. Four interventions were modelled in four demographic groups in 2020 for a total of 16 intervention scenarios. The effect of 0.5, 2.0, and 4.0 g/day reductions in daily salt consumption, along with adherence to the World Health Organization guidelines of a maximum of 5.0 g of salt each day, was modelled in the entire population, including the overweight and obese, the elderly, and diabetics. In each scenario, the number of averted incident cases of acute myocardial infarction and stroke, along with the disability-adjusted life years up to 2050, was monitored. We found 4.0 g/day reductions in salt consumption were the most effective when implemented across the entire population, resulting in 24,000 averted incident cases of cardiovascular disease and 215,000 disability-adjusted life years over 30 years. This is a large figure when compared with the 29,200 projected annual incident cases of cardiovascular disease in 2050. When targeted at specific high-risk demographic groups, the largest effects were observed in the overweight and obese, with the same intervention yielding 10,500 averted incident cases of cardiovascular disease and 91,500 disability-adjusted life years. Quantifying the benefits of salt reduction initiatives revealed a significant impact when administered across the entire population or the overweight and obese. Health promotion efforts directed toward sustainably reducing salt consumption will help to lower the chronic disease burden on the healthcare system in years to come. 相似文献
55.
56.
Bio—Normalizer(BN)对体外鼠胚大脑神经细胞缺氧损伤保护作用的研究 总被引:1,自引:0,他引:1
目的:为研究Bio-Normalizer(BN)对大脑神经细胞缺氧损伤的保护作用,并探讨其机制。方法:本研究采用无血清体外细胞培养方法,培养鼠胚大脑神经细胞,将神经细胞造成缺氧损伤,在无血清培养液中加入不同剂量的BN,观察BN对缺氧损伤的保护作用。将细胞分为4组,Ⅰ组为缺氧BN浓度为0mg/ml组;Ⅱ组为缺氧BN浓度为0.1mg/ml组,Ⅲ组为缺氧BN浓度为0.5mg/ml组;Ⅳ组为非缺氧BN浓度为0mg/ml组。在倒置显微镜下观察细胞生长发育的情况,于细胞培养后的第4天收集细胞,测定生化指标,同时进时光镜和电镜病理检查。结果:缺氧0.1mgBN/ml组的神经细胞MTT及NSE活性均高于缺氧0mgBN/ml组,并有显著差别(P<0.05);形态学观察结果也显示缺氧0.1mgBN/ml组和0.5mgBN/ml组的神经细胞缺氧损伤后恢复明显好于缺氧0mgBN/ml组。结论:BN对大脑神经细胞缺氧损伤恢复具有明显的促进作用。 相似文献
57.
目的验证JOA X-线骨质疏松诊断标准的可靠性.方法47名女性病人(年龄65.3±7.2岁)行腰椎常规X-线检查和第三腰椎正、侧位DEXA骨密度测量.用t检验验证X-线骨质疏松等级间骨密度的差异性,用Spearman相关性分析法检验X-线骨质疏松等级与骨密度值的相关性.结果X-线骨质疏松等级间骨密度具有显著性差异(P<0.01),X-线骨质疏松等级与第三腰椎侧位骨密度值之间相关性最高(r=0.714).结论通过腰椎X-线片按照JOA标准划分骨质疏松等级,可以作为粗略检查腰椎骨质疏松的方法. 相似文献
58.
新型免疫抑制剂霉酚酸酯治疗狼疮性肾炎 总被引:23,自引:0,他引:23
目的观察新型免疫抑制剂霉酚酸酯(M.MF)治疗狼疮性肾炎的临床疗效和安全性。方法经肾活检证实的20例狼疮性肾炎,给予糖皮质激素联合MMF治疗。MMF初始剂量1.0~1.5g/d,治疗时间321个月,平均(10.9±6.2)个月。结果MMF治疗后24h尿蛋白定量从治疗前的平均5.55g下降至1.54g;d清白蛋白治疗前平均26.87g升至39g;6/8例肾功能不全患者3个月内Scr恢复正常;d清自身抗体产生明显减少,补体上升,其中ANA转阴率3个月达63%,6个月达81%;抗ds-DNA由治疗前23.77IU/ml下降至9.19IU/ml;2例重复活检,肾小球活动性病变明显减轻。MMF治疗的不良反应较少,偶有白细胞减少、感染、带状疱疹等。结论MMF对于各型狼疮性肾炎,尤其是Ⅳ型重症狼疮,经传统治疗无效者均有较好疗效,且长期应用不良反应少。 相似文献
59.
目的:观察中药解郁胶囊对老年抑郁症的临床疗效和安全性。方法:选取2020年11月至2021年12月甘肃中医药大学附属医院住院或门诊患者200例作为研究对象,按照纳入标准最终产生研究观察对象100例,健康对照组来自我院组织的年龄在60~80岁的健康体检的老年人100例。观察组中男37例,女63例,对照组中男43例,女57例。对照组采取常规治疗,观察组采取中医综合疗法治疗。对2组患者治疗前后减分情况、中医证候分析、服药及依从情况、不良反应及抑郁焦虑因子等无创性指标的影响。结果:对老年抑郁症的治疗效果主要从汉密尔顿抑郁量表减分情况及证候减分率体现,2组经过12个月中药和抗抑郁综合治疗,中医证候量表减分率(8.2±3.1)和(7.8±3.2),比对照组的(8.8±3)与(8.4±3.6),P值为0.001 6和0.001 3,治疗前后均有明显变化,差异有统计学意义(P<0.05),中医证候量表减分率比较,差异有统计学意义(P<0.05),从服药后出现的不良反应来看,中医综合观察组应明显低于对照观察组,差异有统计学意义(P<0.05)。从中医组治疗患者的依从性分析,差异有统计学意义(P<0.05)。结论:中药解郁胶囊与中医综合治疗患者治疗效果显著,依从性更佳。 相似文献
60.
目的探究动态增强磁共振成像(DCE-MRI)用于评估女性乳房乳头乳晕血供特点的可行性,为乳房整形手术提供乳头乳晕的血供参考。方法从2012年3月至2019年10月华中科技大学同济医学院附属同济医院影像数据库中收集女性乳腺DCE-MRI图像资料,选择未发现肿物的正常乳房的DCE-MRI图像进行研究。在西门子工作站将患者乳腺DCE-MRI图像通过图像减影获取乳房血管图像,分别对轴位、冠状位和矢状位的最大密度投影(MIP)图像进行评估,结合三维MIP图像识别所有供应乳头乳晕的血管。乳头乳晕的血供被划分为内上、内侧、内下、外上、外侧、外下、中央、上方和下方9个象限,对各个象限血管进行统计和分析,并测量血管至乳房皮肤表面投影的最大距离。采用SPSS 19.0软件进行统计分析,通过卡方检验分别比较左侧与右侧乳房的乳头乳晕复合体(NAC)血供象限分布构成比。计算血管到皮肤距离的平均值、标准差及95%置信区间,通过方差分析比较各象限血管至皮肤距离的差异。P<0.05为差异具有统计学意义。结果共收集到245例患者490只女性乳房DCE-MRI图像,其中97例患者97只乳房发现有乳腺肿物,其余393只为正常乳房(97例单侧乳房、148例双侧乳房),将其作为研究对象。患者年龄23~72岁,平均43.7岁。393只乳房(左侧200只、右侧193只)共发现有637条(左侧311条、右侧326条)乳头乳晕供应血管。在637条血管中,内上象限269条(42.2%),外上180条 (28.3%),内侧57条(8.9%),下方37条(5.8%),中央30条(4.7%),内下25条(3.9%),外下25条(3.9%),上方11条(1.7%),外侧3条(0.5%)。卡方检验表明左侧乳房和右侧乳房在NAC血供象限分布构成比差异无统计学意义(χ2 =6.4,P=0.602)。除中央象限血管以外,所有血管到皮肤表面投影最大距离的平均值为0.91 cm, 95%置信区间为0.86~0.96 cm。方差分析表明各象限供血血管到皮肤投影的最大距离,差异有统计学意义(F=11.4,P<0.001)。结论 DCE-MRI可以清晰地显示乳头乳晕的血供来源。乳头乳晕血供主要来源于内上象限和外上象限的血管,血管在皮下约1 cm深度走行。 相似文献