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191.
192.
芩荑合剂吸入对哮喘豚鼠气道嗜酸粒细胞凋亡的影响 总被引:8,自引:1,他引:8
目的 :研究芩荑合剂对哮喘豚鼠气道嗜酸粒细胞 (Eos)凋亡的影响。方法 :2 4只豚鼠随机分为 3组 ,即对照组、模型组和芩荑合剂吸入组 (1 8ml kg) ,每组 8只 ,以卵蛋白吸入致敏激发制作哮喘豚鼠模型 ,密度梯度分离法分离支气管肺泡灌洗液 (BALF)中Eos ,应用流式细胞术 (FCM)检测其凋亡率。结果 :对照组豚鼠BALF中Eos计数为 0 32± 0 11× 10 9 L ,Eos凋亡率为 14 1±4 2 % ;与对照组比较 ,模型组豚鼠BALF中Eos显著增加 (P <0 0 1) ,Eos凋亡率显著下降 (P <0 0 1) ;芩荑合剂吸入组同模型组相比 ,BALF中Eos显著减少 (P <0 0 1) ,Eos凋亡率显著增加 (P <0 0 1) ,且BALF中Eos数量与Eos凋亡率呈显著性负相关 (r=- 0 895 ,P <0 0 1)。结论 :Eos凋亡异常是支气管哮喘的一个重要的发病机制 ;芩荑合剂吸入可促进气道内Eos凋亡 ,减少Eos聚集 ,从而减轻哮喘气道炎症。 相似文献
193.
夏枯草注射液为主治疗中晚期胃、大肠癌30例临床观察 总被引:17,自引:0,他引:17
选符合入选条件的中晚期胃、大肠癌住院患者50例,随机分为治疗组30例、对照组20例。治疗组予夏枯草注射液静滴,对照组口服平消胶囊,疗程均为30天。结果:治疗组中医症侯综合疗效明显优于对照组(u=2.5200,P=0.0122);生存质量明显提高,且优于对照组(t=2.4776,P=0.0174);治疗组每治疗10人,可较对照组减少1例实体瘤进展(PD)患者(NNT=10);治疗组IFN—γ明显升高(t=2.3960,P=0.0204),IL12、IFN—γ升高优于对照组(t=2.9720,P=0.0047;t=2.1944,P=0.0361)。结论:夏枯草注射液对中晚期胃与大肠癌证属脾胃或大肠湿热证者有较好的应用价值,作用优于平消胶囊。 相似文献
194.
目的 研究应用神经反应遥测 (neuralresponsetelemetry ,NRT)技术 ,测试电诱发复合动作电位 (electrically evokedcompoundactionpotential,ECAP)阈值以指导小儿人工耳蜗映射调图的策略与时机。方法 应用NRT3 0软件对幅值增长函数进行线性拟合 ,确定ECAP阈值。比较 6例儿童植入者在术后 1、2、3个月ECAP阈值的变化 ,同时比较 7例儿童术中、术后ECAP阈值的差异。结果ECAP幅值增长函数在接近阈值或进入饱和时不再呈线性。术后ECAP阈值保持稳定。各导电极的术中ECAP阈值比术后阈值平均高约 15CL ,二者有显著性相关 (R2 =0 915 4)。结论 应选取幅值增长函数的直线段部分进行拟合以确定ECAP阈值。术后应用ECAP阈值指导小儿映射调图时 ,测试一次ECAP阈值即可。术中ECAP阈值可用作开机时映射图的C值 相似文献
195.
Cornelius Schüle Flavia di Michele Thomas Baghai Elena Romeo Giorgio Bernardi Peter Zwanzger Frank Padberg Augusto Pasini Rainer Rupprecht 《Neuropsychopharmacology》2003,28(3):577-581
There is evidence from preclinical and clinical studies that concentrations of neuroactive steroids are altered in depression and normalize after antidepressant pharmacotherapy. However, no data are available concerning the impact of sleep deprivation on the concentrations of neuroactive steroids. A total of 29 drug-free patients (12 men, 17 women) suffering from major depression according to DSM-IV criteria were treated with partial sleep deprivation (PSD). Response to PSD was defined as a reduction of at least 30% according to the six-item version of the Hamilton depression scale (6-HAMD). Plasma samples were taken the day before and after PSD (days 0 and 1) and after one night of recovery sleep (day 2) at 8:00 am. The samples were quantified for neuroactive steroids by means of a highly sensitive and specific combined gas chromatography/mass spectrometry analysis. There was no influence of PSD on the concentrations of neuroactive steroids either in PSD responders (n=20) or in nonresponders (n=9). However, nonresponders showed significantly higher concentrations of 3alpha,5alpha-tetrahydroprogesterone (3alpha,5alpha-THP), 3alpha,5beta-tetrahydroprogesterone (3alpha,5beta-THP), and dehydroepiandrosterone (DHEA) before or after PSD compared to responders. In contrast to antidepressant drugs, which correct the dysequilibrium of neuroactive steroids in major depression within several weeks, PSD does not affect the concentrations of neuroactive steroids either in responders or in nonresponders. 相似文献
196.
Carolina Battellino Roxane Piazza Ana M M da Silva Yara Cury Sandra H P Farsky 《Toxicon》2003,41(5):583-593
Intravenous administration of antibothropic antivenom (BAv) neutralises the systemic effects, but does not efficiently reverse the local symptoms elicited by the Bothrops jararaca venom (BjV). The mechanisms involved in this poor protection have not been clarified. In this work, intravital microscopy studies were carried out to determine the efficacy of different schedules of BAv treatment on local effects evoked by topical application of BjV in the microcirculatory network of the internal spermatic fascia of Wistar rats. Results demonstrated that BAv administration 15 min before, simultaneously with, or 15 min after BjV application did not totally reverse the local symptoms, represented by disturbances of coagulation, development of haemorrhage lesions, vascular permeability increase and increment on leukocyte-endothelium interactions. This lack of effectiveness neither reflects an inadequate amount of specific antibodies in the antivenom against toxins responsible for local effects nor an insufficient dose of circulating BAv during the assays. Administration of fluorescein isothiocyanate (FITC) labelled-BAv showed the dynamics of distribution of the antivenom in the microcirculatory network. Images obtained from prior and simultaneously treated animals showed that the antivenom remains at luminal side of vessels before venom application, and the latency time to antivenom leakage is coincidental to that for local effects evoked by the venom. In addition, images from posterior treatment demonstrated that the intense alterations in the microcirculatory network impair antivenom distribution at the site of injection. Together, our data show that the lack of effectiveness of antivenom therapy is due to impaired and delayed venom and antivenom interaction at the site of injury. 相似文献
197.
A Patócs E Karádi M Tóth I Varga N Szücs K Balogh J Majnik E Gláz K Rácz 《European journal of cancer prevention》2004,13(5):403-409
The aims of this study were to estimate the prevalence of phaeochromocytomas among adrenal tumours and to analyse the clinical and biochemical features of sporadic and hereditary tumours. Our series of 609 adrenal tumours evaluated between January 1995 and July 2003 was reviewed. Catecholamine content in phaeochromocytoma tissues was also determined and correlated with clinical behaviour and biochemical parameters of patients. Forty-one (6.7%) of the 609 patients had phaeochromocytomas, of which 28 were sporadic (25 benign and three malignant) and 13 (all benign) were associated with hereditary diseases (multiple endocrine neoplasia type 2A in seven cases from four unrelated families carrying mutations of the RET gene, von Hippel-Lindau disease in two unrelated cases with mutations of the VHL gene, and type 1 neurofibromatosis in four unrelated cases). Bilateral tumours were found in three patients with hereditary syndromes and in one sporadic case. Tumour diameter was slightly but not significantly greater in patients with hereditary than in those with sporadic tumours. Systolic but not diastolic blood pressure was significantly higher in patients with sporadic compared with those with hereditary tumours, but comparison of other clinical data and biochemical parameters indicated an absence of significant differences in the mean age, presenting symptoms, heart rate, or fasting serum glucose levels. Tissue catecholamine content measured in 8 sporadic and 5 hereditary phaeochromocytomas was highly variable and it failed to show significant differences between hereditary and sporadic tumours. These results indicate a high proportion of hereditary diseases among patients with phaeochromocytomas. Genetic and clinical testing for hereditary diseases may be of great help to offer an appropriate treatment, follow-up and family screening for these patients. 相似文献
198.
人α干扰素诱导骨肉瘤细胞Anoikis凋亡 总被引:1,自引:0,他引:1
目的:恶性肿瘤细胞逃避Anoikis凋亡的特性是其原位侵袭和远处转移的一个重要原因。本文旨在研究应用人干扰素(IFN)α2a诱导骨肉瘤细胞出现Anoikis凋亡,并深入探讨其产生机理及信号传导途径。方法:采用抑制接触培养法建立细胞Anoikis凋亡诱导模型。观察IFN-α2a诱导骨肉瘤细胞MG-63产生的Anoikis凋亡。TUNEL法形态学检测MG-细胞凋亡,流式细胞仪定量检测细胞凋亡程度和细胞表面整联蛋白受体表达。特异性底物切开法检测半胱氨酸天门冬氨酸特异性蛋白酶(cysteine aspartate-specific proteases,caspase)信号途径。结果:人IFN-α2a可明显诱导骨肉瘤细胞MG-63产生Anoikis现象,并诱导了MG-63细胞caspase-8和caspase-3的活性,但IFN对整联蛋白亚单位α4,α5及αv无明显影响,上述整联蛋白封闭抗体对IFNα-2a诱导的MG-63细胞Anoikis凋亡无明显影响。结论:人干扰素α2a可以在体外通过调节细胞caspase信号途径,诱导骨肉瘤细胞MG-63产生Anoikis现象,从而抑制骨肉瘤的转移。 相似文献
199.
薄层色谱法测定阿德福韦酯有关物质 总被引:5,自引:0,他引:5
目的:建立阿德福韦酯有关物质薄层色谱检查法。方法:反相薄层色谱法,甲醇-水(3:1)为展开剂,在紫外光254nm下检视。结果:经方法学验证本法能有效分离并检测阿德福韦酯中的有关物质。最小检测限为0.1μg。结论:反相薄层色谱法避免了阿德福韦酯在硅胶薄层色谱法中发生分解的现象,且分离效果好,检测灵敏度高。 相似文献
200.
JP Bound PW Harvey BJ Francis F Awwad AC Gatrell 《Archives of disease in childhood》1997,76(2):107-112
OBJECTIVE: To analyse the prevalence of neural tube defects in small geographical areas and seek to explain any spatial variations with reference to environmental lead and deprivation. SETTING: The Fylde of Lancashire in the north west of England. DESIGN: Cases were ascertained as part of a prospective survey of major congenital malformations in babies born in the Fylde to residents there between 1957 and 1981. A matched case-control analysis used infants with cardiovascular system, alimentary tract, and urinary system malformations as controls. Conditional logistic regression was used to assess the effects of more than 10 micrograms/l lead in drinking water and the Townsend deprivation score. RESULTS: The prevalence of neural tube defects in 1957-73 was higher in Blackpool, Fleetwood, and North Fylde, whereas the three control groups showed no significant spatial variation. In 1957-81 mothers living in electoral wards with either a higher proportion of houses with more than 10 micrograms/l lead in the water or a higher deprivation score had a greater risk of having a baby with a neural tube defect. For spina bifida and cranium bifidum alone, this was also true. For anencephaly, deprivation was less important although the effect of lead was still seen. In some neural tube defects, lead may act independently of other possible factors associated with deprivation. It seemed unlikely that lead levels changed significantly during the survey. The percentage of houses with 10 micrograms/l or more of lead in the water in 1984-5 was similar to that found in Great Britain 10 years previously. CONCLUSION: There is evidence to suggest that lead is one cause of neural tube defects, especially anencephaly. This could link the known preventive actions of hard water and folic acid. Calcium is a toxicological antagonist of lead. One cause of a deficiency of folic acid is impaired absorption secondary to zinc deficiency, which may be produced or exacerbated by lead. 相似文献