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991.
Nobuyuki Tanaka Yutaka Kimijima Masafumi Mimura Akira Yamaguchi Shizuko Ichinose Gen-iku Kohama Masaaki Satoh 《Medical Electron Microscopy》1998,31(3):156-161
A rare case of lentigo maligna in the oral cavity was investigated by light and electron microscopy. Cutaneous lentigo malignas often develop to malignant melanomas. However, the electron microscopic examination revealed that even though there were a large number of melanosomes, most of them were late stage and had membrane structure, and positive staining with HMB-45 was not recognized. From our findings, it is difficult to conclude that oral lentigo malignas develop malignant melanomas, and thus further studies are needed. 相似文献
992.
Sex differences in plasma cocaine levels and subjective effects after acute cocaine administration in human volunteers 总被引:3,自引:3,他引:0
S. E. Lukas M. Sholar L. H. Lundahl X. Lamas E. Kouri J. D. Wines L. Kragie J. H. Mendelson 《Psychopharmacology》1996,125(4):346-354
Gender differences after acute cocaine administration have received little attention in spite of the fact that males and females respond differently to many drugs. Seven male and seven female occasional cocaine users received both an intranasal dose of cocaine hydrochloride (0.9 mg/kg) and placebo powder in a randomized order and reported subjective effects via an instrumental joystick device and various questionnaires. Blood samples were withdrawn at 5-min intervals to assess pharmacokinetic differences. Male subjects achieved the highest peak plasma cocaine levels (144.4 ± 17.5 ng/ml), detected cocaine effects significantly faster than females and also experienced a greater number of episodes of intense good and bad effects. Women studied during the follicular phase of their menstrual cycle had peak plasma cocaine levels of 73.2 ± 9.9 ng/ml, which was significantly higher than when they were studied during their luteal phase (54.7 ± 8.7 ng/ml), but there were no differences in their subjective reports of cocaine effects. In spite of the different cocaine blood levels and subjective effects, peak heart rate increases did not differ between males and females suggesting that women may be more sensitive than males to the cardiovascular effects of cocaine. These data suggest that there are significant gender and menstrual cycle differences in the response to acute intranasal cocaine administration and these differences may have implications for the differential abuse of this drug.This paper is dedicated to Xavier Lamas, MD, PhD, who lost his life while ascending Mt. Everest, August 1995 相似文献
993.
Although the esophagus is the most frequent site ofCandida infections in the gastrointestinal tract, and many clinical studies about it have been reported, little attention has been
directed toward experimental candidiasis of the esophagus, especially with regard to its ultrastructure. Using transmission
electron microscopy, this study was performed to clarify the ultrastructure of experimental lesions, obtained from five New
Zealand white male rabbits which were given a suspension ofCandida albicans cells (107/ml) for 13 days. The results showed that the lesions consisted of exfoliating, squamous epithelial cells with mycelial elements
ofCandida albicans cells penetrating through them, and that a widened intercellular space between individual cells in the area of candidial
invasion seems to be a characteristic finding of candidial infection.
A part of this study was presented at the 25th Annual Meeting of the Clinical Electron Microscopy Society of Japan, Matsumoto,
September 28–30, 1993. 相似文献
994.
Volker Stefanski George F. Solomon Arthur S. Kling John Thomas Susan Plaeger 《Brain, behavior, and immunity》1996,10(4):364-379
The impact of social defeat on lymphocyte subpopulations and T helper subsets was investigated in Long Evans rats. CD4 T helper cell subsets with distinct functional properties and different cytokine profiles can be distinguished by using the mAbs OX-22 (anti-CD45RC) and OX-7 (anti-CD90, Thy1.1). Male intruders were exposed for 2, 6, or 48 h to aggressive resident pairs. All intruders were attacked upon introduction and were defeated as indicated by frequent display of full submissive postures. After 2 and 48 h of confrontation, drastic but differential effects on blood leukocyte numbers, CD4 and CD8a cells, and CD4 subsets were evident. However, after 6 h of confrontation most lymphocyte subset numbers corresponded to baseline levels. Focusing on CD4 subsets after 2 h of confrontation, we demonstrated that only the number of the CD45RC−CD90−subset declines, whereas neither the number of the CD45RC+CD90−subset nor the number of the CD45RC−CD90+subset (recent thymic emigrants) was influenced. Con A stimulation of sorted subsets identified the CD45RC−CD90−as a poor producer of IFN-γ. The data clearly demonstrate that social factors might differentially influence not only T cell subsets but also T helper cell subsets with distinct cytokine profiles in a possibly time-dependent manner. Such a stress-induced shift toward a CD45RC+CD90−-dominated milieu may have important consequences in interpreting results obtained from mitogenic stimulation of blood lymphocytes and cytokine production profiles measured after such a stimulation. In addition, a shift toward a CD45RC+CD90−dominance may modify the type and magnitude of immune response, at least temporarily. 相似文献
995.
Haemodynamic effects of DPI 201-106, following single intravenous dose administration to patients with moderate cardiac failure 总被引:1,自引:0,他引:1
HOGAN J. C.; GREENBAUM R. A.; LUNNON M. W.; HILSON A. J. W.; EVANS T. R. 《European heart journal》1988,9(5):498-502
DPI 201106 is a novel compound unrelated to other cardioactiveagents and has been shown to have an inotropic effect in animalpreparations. The drug was given by intravenous infusion (20mg over 10 min) to 10 patients with moderate cardiac failureand the haemodynamic effects measured at intervals up to 1 hfollowing infusion. Maximal effects were seen immediately followingthe infusion of DPI 201106. Cardiac index showed an increasefrom baseline 2·72 (0·16) 1 min-1 m-2 to 3·18(0.21) 1 min-1 m-2 at the end of infusion (P<0·001).Subsequent values were not significantly raised. Pulmonary capillarywedge pressure and pulmonary artery pressure fell from 27·6(3·2) and 36·9 (4·4) to 15·3 (3·6)and 24·2 (4·9) mmHg, respectively (P<0·001in both cases). A statistically significant effect on cardiacindex was not seen at 1 h. However, pulmonary pressures remainedreduced at this point. Radionuclide ejection fraction showeda significant increase from 15·4 (1·5) to 21·9(2·2)% (P<0·005) at the end of infusion, andmaintained a significant increase at 1 h. Having demonstratedbeneficial, acute haemodynamic effects in this study, furtherwork should be undertaken with DPI 201106 to investigatethe effect of chronic treatment in patients with cardiac failure. 相似文献
996.
Prognostic value of somatosensory- and motor-evoked potentials in patients with a non-traumatic coma
Josef Zentner Alois Ebner 《European archives of psychiatry and clinical neuroscience》1988,237(3):184-187
Summary A total of 28 patients with non-traumatic coma were studied both with somatosensory- and motor-evoked potentials. While somatosensory-evoked potentials (SEP) have proved to be useful in predicting the outcome in patients with severe brain damage, the aim of this study was to find out whether the additional evaluation of motor-evoked potentials (MEP) could contribute to a better prediction of the outcome than SEP alone. Our results clearly indicate that in terms of prognostic value, SEP are superior to MEP. Nine patients with bilaterally preserved MEP died, while all of the patients with bilaterally preserved SEP and a central conduction time 6.5 ms survived, with a Glasgow outcome score of 1 to 3. Therefore, we cannot recommend the inclusion of MEP in the prognostic evaluation of patients with non-traumatic coma. 相似文献
997.
T. Baba S. Murabayashi K. Aoyagi T. Ishizaki 《European journal of clinical pharmacology》1988,35(1):9-15
Summary The effects of oral dilevalol (an R, R-isomer of labetalol), a new -adrenoceptor blocker with 2-receptor stimulating and -recepter blocking properties on blood pressure, renal function, plasma renin activity (PRA) and plasma aldosterone have been studied in 15 patients with mild-to-moderate essential hypertension treated with it for 6 weeks.Two patients with apparent treatment failure and one patient who developed muscle pain and cramps, and had an elevated creatine phosphokinase level, were excluded from the study.Dilevalol monotherapy 100 mg once daily for 6 weeks significantly lowered both the systolic and diastolic blood pressure compared to placebo. Total renal vascular resistance was significantly reduced, and RBF and GFR remained unchanged. Dilevalol significantly decreased PRA.The results suggest that prolonged daily treatment with dilevalol preserves renal function and produces a concomitant hypotensive action in patients with mild-to-moderate essential hypertension. The ancillary pharmacological properties of dilevalol rather than PRA suppression may be relevant to its renal effects. 相似文献
998.
目的:探讨体轴发育抑制因子(Axin1)调节骨骼肌葡萄糖转运蛋白4(GLUT4)蛋白表达的作用及其机制。方法:利用RNAi干扰的Axin1腺病毒(Ad-siAxin1)感染C2C12小鼠骨骼肌细胞敲低Axin1,荧光显微镜和MTS实验明确Ad-siAxin1最佳感染浓度和时间。分别用携带绿色荧光蛋白的腺病毒(Ad-GFP)、Ad-siAxin1、载体质粒(vector)和Axin1质粒转染C2C12小鼠骨骼肌细胞敲低或过表达Axin1蛋白,Western印迹检测Axin1、端锚聚合酶蛋白(TNKS)和GLUT4蛋白水平。结果:荧光显微镜和MTS实验结果显示,在C2C12小鼠骨骼肌细胞中Ad-siAxin1作用的最佳浓度和时间分别为160μL和48 h。Western印迹结果显示,与Ad-GFP组相比,Ad-siAxin1组中Axin1蛋白降低(t=6.746,P<0.01)。Ad-siAxin1组TNKS蛋白水平降低(t=4.019,P<0.05),GLUT4蛋白水平下调(t=3.248,P<0.05)。与vector组相比,转染Axin1质粒后,Axin1蛋白水平上... 相似文献
999.
背景 流行病学研究表明,绝经后女性的高血压患病率高于老年男性。近年来,有关绝经后高血压的临床表现、病理特征、发病机制、治疗方法等受到越来越多的关注,但由于受到研究设计、样本量、人群特征、资源不足等因素的影响,其危险因素的研究结果不一致且缺乏全面报道。目的 运用系统评价方式探讨女性绝经后高血压的危险因素,为更好地预防和管理绝经后高血压提供循证证据。方法 于2022年1—5月,计算机检索中国知网、万方数据知识服务平台、中国生物医学文献服务系统、PubMed、EmBase、the Cochrane Library、Web of Science电子数据库,获取与绝经后高血压危险因素相关的队列及病例对照研究。检索时限为建库起至2022-05-20。由2名研究者独立根据纳入和排除标准筛选文献、提取资料,采用纽卡斯尔-渥太华量表(NOS)对所提取的文献进行偏倚风险评估,将得分≥6分(高质量)的文献纳入研究,最后采用RevMan 5.3对其进行Meta分析。结果 共纳入10篇文献,5篇为队列研究,5篇为病例对照研究,共涉及16个危险因素,总样本量为34 864,且均为高质量文献。Meta分析结果显示,... 相似文献
1000.
目的:探索种植体黏膜下微生物在健康种植体和种植体周炎中的构成与差异,并分析与临床指标存在相关性的菌种,为种植体周炎的病因学研究提供参考。方法:采用横断面研究,共纳入49例患者,20例为健康种植体,29例为种植体周炎,共采集49份黏膜下微生物样本进行16S核糖体RNA(16S ribosomal RNA, 16S rRNA)基因高通量测序。对两组样本的多样性、菌群构成和差异物种进行分析和比较,采用Spearman相关性分析评价菌种与探诊深度(probing pocket depth, PPD)之间的相关性。结果:健康组的α多样性显著低于种植体周炎组[Chao1指数:236.85±66.13 vs. 150.54±57.43,P<0.001; Shannon指数:3.42±0.48 vs. 3.02±0.65,P=0.032]。主成分分析显示,两组样本的群落结构差异有统计学意义[相似性分析(analysis of similarities, ANOSIM),R2=0.243,P=0.001]。与健康种植体相比,种植体周炎黏膜下菌斑中的牙周致病菌显著增加,包括红色... 相似文献