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小檗胺对小鼠脾细胞毒性T淋巴细胞活性的抑制作用 总被引:2,自引:0,他引:2
小檗胺对小鼠脾细胞毒性T淋巴细胞活性的抑制作用罗崇念,林新,王立为,赵扬,谢蜀生,肖培根(中国医学科学院药用植物研究所,北京100094;北京医科大学免疫学教研室,北京100083)小檗胺(berbamine)是小檗属植物中的一种双节基异喹啉类生物碱... 相似文献
23.
Pierre-Michel Cahen Jean-Christophe Turlot Robert M. Frank Gérard Clement Gil Seckler 《Community dentistry and oral epidemiology》1987,15(4):211-215
A representative sample of 1650 children randomly selected in the 6-15-yr-old schoolchild population of Strasbourg was examined by well-calibrated examiners. The prevalence of caries was determined with the DMFT, DMFS and dft indices using bitewing radiographs. Plaque, calculus and gingival indices were also determined. The results obtained were compared with the initial study of 1974 performed in Strasbourg using the same epidemiologic methods. Whereas no important variations were observed in caries prevalence of primary teeth, a significant reduction of caries activity was observed in DMFT and DMFS indices in all age groups. There was a reduction of these two indices of respectively 32% and 33% in the 12-yr-old children. The reduction was the most significant on approximal surface lesions. A statistically significant decrease of the calculus and gingival indices was also observed between 1974 and 1984. A less significant decrease was observed for the plaque index. 相似文献
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Abstract Until recently, the few available chlorhexidine mouthrinse products have been 0.2% formulations. However, concentrations of 0.12% chlorhexidine appear as effective as 0.2%, if the volume of the rinse is increased to 15 ml. Since the mere incorporation of chlorhexidine in a formulation does not guarentee availability of the antiseptic, it would seem reasonable to evaluate or compare all products. This is particularly the case when other ingredients, such as fluoride are added. The 1st study compared the effect of a 0.12% chlorhexidine rinse with a 0.12% chlorhexidine/0.022% sodium fluoride rinse for effects on plaque re-growth. The study was a 7-day, blind, randomised, 2-cell cross-over design with a baseline control run in period, in which 18 subjects participated. Both chlorhexidine products significantly reduced plaque compared to control but the chlorhexidine fluoride rinse was less effective than the chlorhexidine only rinse. The 2nd study assessed the propensity of the chlorhexidine rinses to induce dietary staining in vitro. For the chlorhexidine fluoride rinse, this was less than the other 0.12% rinse and a commonly used 0.2% product. The data in vivo and in vitro suggest reduced chlorhexidine availability from the chlorhexidine fluoride product which appears to cause some loss of efficacy. 相似文献
26.
We have used quantitative light microscopic autoradiographic techniques to analyze changes in muscarinic cholinergic receptors in the hippocampus in Alzheimer type dementia (ATD). The density and distribution of muscarinic cholinergic receptors has been correlated with the density of neurons, neuritic plaques and neurofibrillary tangles in the CA1 subfield of the hippocampus of control and ATD patients. The number of pyramidal cells per mm2 in the CA1 sector was significantly decreased in ATD cases as compared to controls, although there were large variations among cases. The most marked reductions in cell counts were observed in patients with a history of profound dementia. The densities of muscarinic receptors, as well as the proportions of M1 and M2 subtypes, in the CA1 sector and dentate gyrus were not significantly different between ATD and old non-demented patients. Neuritic plaques, even in high numbers, did not affect the density of muscarinic receptors; moreover, the densities of receptors over the neuritic plaques did not differ from the surrounding neuropil. However, in some ATD cases there was a marked decrease in the concentration of these receptors in the CA1 sector and subiculum, with no change in the proportions of muscarinic receptor subtypes. These patients exhibited frequent extracellular remnants of neurofibrillary tangles (ghost tangles), but scarce neuritic plaques, and were those showing severe losses of pyramidal cells. There was a significant positive correlation between the total concentration of muscarinic receptors in the CA1 and the density of pyramidal cells, suggesting that decreases in receptor concentration result from a severe neuronal loss. We observed that the ratio of muscarinic receptors per pyramidal cell was significantly increased in ATD patients. This might indicate a possible upregulatory mechanism for muscarinic receptors in the population of remaining neurons in ATD. However, decreases of receptor numbers following severe neuronal fall out suggest that compensatory mechanisms are no longer possible in such cases. The question is raised whether these differences between cases reflect different diseases or different stages of the same disease. 相似文献
27.
Objective Report of two cases of exudative discoid and lichenoid dermatosis (Sulzberger-Garbe), with typical penile lesions. Differential diagnosis of persistent penile plaques. Background Following remission of the generalized eruption of exudative discoid and lichenoid dermatosis (Sulzberger-Garbe), it is not unusual to see a single remaining lesion localized on the penis. Since Sulzberger et al. (Sulzberger MB, Witten VH, Hunt JA. Puzzling persistent penile plaques. Arch Dermatol 1956:73:101-109) reviewed dermatoses presenting with puzzling persistent penile plaques in 1955, further dermatoses have evolved as important differential diagnoses. Much controversy has arisen as to the justification of exudative discoid and lichenoid dermatosis (Sulzberger-Garbe) as a disease entity. Conclusions Diagnosis of most cases of persistent plaques of dermatitis on the penis is possible with a careful examination of the entire skin, and a thorough history to discover past lesions. The possibility of malignancy makes a biopsy mandatory. Exudative discoid and lichenoid chronic dermatosis (Sulzberger-Garbe) typically responds well to systemic steroids. Intrale-sional triamcinolone acetonide has been demonstrated to be effective in the treatment of a persistent penile plaque in exudative discoid and lichenoid dermatosis (Sulzberger-Garbe), and may be helpful in discontinuing or reducing systemic therapy to a level compatible with long-term treatment. 相似文献
28.
J. A. P. van de Nes A. A. Sluiter C. W. Pool W. Kamphorst R. Ravid D. F. Swaab 《Brain research》1994,655(1-2)
The monoclonal antibody Alz-50 is directed against Alzheimer's disease-related modified tau proteins and reveals cytoskeletal changes, i.e. neurofibrillary tangles and dystrophic neurites. The present study shows that, in the hypothalamus of non-demented control subjects, this same antibody gives a distinctive staining pattern of a subpopulation of somatostatin neurons and beaded fibers. Furthermore, Alz-50 occasionally recognizes somatostatin-containing cell bodies and dystrophic neurite-like fibers in the (neuritic) senile plaques of AD patients. These observations have direct consequences for the interpretation of Alz-50 staining in diagnostic usage and for the assessment of Alzheimer's disease-like changes induced by β-amyloid in experimental animal brains. On dot spotting, Alz-50 was found to bind to a number of fragments from the somatostatin precursor, of which somatostatin15–28 stained best. Preadsorption of Alz-50 by somatostatin15–28, as well as other specificity tests, failed, however, to provide any clue to the nature of the unknown compound(s) stained in the control hypothalamus. 相似文献
29.
妊娠相关血浆蛋白A水平与不稳定心绞痛患者冠状动脉狭窄病变形态的关系 总被引:2,自引:2,他引:0
[目的]探讨不稳定型心绞痛患者妊娠相关血浆蛋白(PAPP-A)水平与高敏C-反应蛋白(hs-CRP)及动脉粥样硬化斑块稳定性的关系.[方法]不稳定型心绞痛组患者42例,稳定型心绞痛组38例.冠状动脉造影前检测PAPP-A和hs-CRP,根据造影结果将冠状动脉病变分为复杂狭窄和光滑狭窄.[结果]稳定型心绞痛组有28例(74%)患者至少有1支血管狭窄≥70%,多于不稳定型心绞痛组的24例(57%),P<0.05;不稳定型心绞痛组中33例(79%)有1处以上的复杂狭窄,多于稳定型心绞痛组(22例,58%,P<0.05);PAPP-A与hs-CRP正相关(r=0.44,P<0.001);不稳定型心绞痛组与稳定型心绞痛组相比,hs-CRP(4.40 mg/L±0.003 mg/L vs 0.48 mg/L±0.016mg/L,P<0.001)和PAPP-A(18.40×10-3 U/L±0.002×10-3U/Lvs 7.79×10-3 U/L±0.001×10-3 U/L,P<0.001),差异均有统计学意义;两组中有复杂狭窄者的PAPP-A和hs-CRP水平显著高于无复杂狭窄者.[结论]PAPP-A可作为评估冠状动脉斑块稳定性的血清学指标之一. 相似文献
30.
Dr C. J. Whitters T. W. Macfarlane D. Mackenzie H. Moseley R. Strang 《Lasers in medical science》1994,9(4):297-303
Pulsed Nd-YAG laser irradiation of bacteria has been suggested as a possible means of treating contaminated intra-oral sites
although relatively few studies have been conducted. In this investigation, the antimicrobial activity of a pulsed Nd-YAG
laser was assessed in vitro for a range of oral bacteria using several pulse energies and exposure durations. Pure cultures
of each organism were lased in saline suspensions followed by standard colony counting techniques for test and control samples.
Microbial inhibition was found to be organism-dependent and varied with energy dose and pulse energy. For all nine test species
120-mJ laser pulses proved more efficient than 80-mJ pulses, with 99.9% kills compared with around 90% kills after exposure
to 1800 pulses. These killing activity levels compare favourably with those achieved with other lasers in vitro. 相似文献