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1.
HA Carpay P Matthijsse M Steinbuch PGH Mulde 《Cephalalgia : an international journal of headache》1997,17(5):591-595
In an open, randomized cross-over study in 124 patients, we compared the efficacy, safety and patient preference of oral and subcutaneous sum triptan in the acute treatment of migraine. Patients were treated for 3 attacks or 3 months and then crossed over. Primary clinical efficacy was defined as a reduction in headache severity on a four-point self-rating scale from severe (3) or moderate (2) to mild (1) or none (0), or mild (1) to none (0). Efficacy was evaluated 2 h after the administration of subcutaneous and 4h after the administration of oral sumatriptan. Subcutaneous sumatriptan was significantly more effective than oral sumatriptan in relieving headache (over all three attacks 78% vs 61% improvement), improving clinical disability (55% vs 41 % improvement) and relieving nausea (69% vs 53%), vomiting (72% vs 32%) and phono- or photophobia (67% vs 49%). Median time to recurrence was shorter after subcutaneous (12.5 h) than after oral sumatriptan (18 h); the number of patients experiencing a recurrence was similar Patients reported more adverse events after subcutaneous sumatriptan (1.32 per attack) than after the oral form (0.85 per attack), but all adverse events were mild to moderate in intensity and of short duration. Patient opinion was more often positive after subcutaneous sumatriptan. These results may be useful in counselling patients to choose between the available marketed formulations of sumatriptan. 相似文献
2.
Pharmacokinetics of orally administered hexobarbital in plasma and saliva of healthy subjects 总被引:1,自引:0,他引:1
M van der Graaff N P Vermeulen P Heij J K Boeijinga D D Breimer 《Biopharmaceutics & drug disposition》1986,7(3):265-272
Hexobarbital (HB) concentrations were determined in plasma and saliva of 8 healthy subjects, following oral administration of 500 mg HB-Na. Mean plasma half-lives were 3.2 +/- 0.1 h, and salivary half-lives 3.3 +/- 0.2 h. Mean plasma clearance was 22.9 +/- 2.3 1 h-1. There was a linear relationship between HB concentrations in saliva and plasma (r = 0.92). Mean salivary levels were 34 per cent of plasma levels. Salivary pH was constant throughout the experiment, 7.06 +/- 0.09. There was an inconsistent tendency of the saliva over plasma ratios to increase as a function of time. The percentage of protein binding calculated from saliva over plasma ratios was in reasonable agreement with in vitro data of equilibrium dialysis, 64.1 +/- 2.6 per cent and 65.9 +/- 0.8 per cent, respectively. The experiment was repeated in 4 subjects, and considerable intraindividual differences were shown to exist in saliva over plasma ratio, half-lives, and protein binding. It was concluded that HB elimination half-lives can relatively accurately be determined from salivary concentrations. Oral plasma clearance can only be estimated if the individual saliva over plasma ratios are known; this would require the taking of at least one blood sample during the experiment. When employing HB as a model substrate for drug metabolizing enzyme activity in vivo, the determination of its pharmacokinetic parameters, particularly oral plasma clearance as a reflection of cytochrome P-450 activity, cannot be achieved by taking saliva samples only. 相似文献
3.
结核分枝杆菌Ag85B/GST融合蛋白表达载体构建及在大肠杆菌中的表达 总被引:1,自引:1,他引:0
目的 构建结核分枝杆菌Ag85B/GSF融合蛋白表达质粒,并在大肠杆菌(E.coli)中诱导表达。方法 以质粒pUC18/Ag85B为模板,用PCR法扩增结核杆菌Ag85B基因,扩增的Ag85B上游含有EcoR Ⅰ酶切位点,下游含有SalⅠ酶切位点;将Ag85B基因定向插入质粒pGEX-4T-1中,构建原核表达质粒pGEX-Ag85B并转化E.coli B121,筛选阳性重组子,限制性内切酶切鉴定和DNA序列测定,异丙基硫代半乳糖苷(IPTG)诱导表达,SDS-PAGE和Westem blot鉴定结果。结果 成功构建原核表达质粒pGEX-Ag85B并表达出Mr约56000大小的Ag85B/GSY融合蛋白,表达量占总菌体的30%。结论 为进一步进行纯化Ag85B蛋白和研究其在膀胱肿瘤治疗中的作用奠定了基础。 相似文献
4.
5.
Genomic in situ hybridization (GISH) successfully differentiated homoeologous genomes in the interspecific hybrid Allium cepa × fistulosum, thus allowing the detection of reciprocal crossover events as label exchanges in separating anaphase I chromosomes. Three of the eight chromosome pairs were positively identified by fluorescence in situ hybridization (FISH) to rDNA sequences. There was a general similarity of the GISH-based label exchange frequencies and metaphase I chiasma frequencies, but with a 20% deficit of chiasmata. Reasons for this apparent deficit are discussed. The locations of chiasmata and label exchanges are in broad agreement. 相似文献
6.
7.
对“红包”现象的深层思考 总被引:1,自引:1,他引:0
本文试将“红包”现象由表及里的进行剖晰.(1)红包现象林林总总,从3点着笔.①红包之“风乍起,吹皱一池春水”;②红包类别、特性;③医患复杂心态(各7种).(2)红包现象的危害;(3)红包的综合治理“八抓”(抓教育,正向导廉;抓道德,自律清廉;抓制度,规范保廉;抓案例,褒贬倡廉;抓经常,时时冷廉;抓监督,约束促廉;抓评价,准绳测廉;抓支部,牢牢固廉). 相似文献
8.
van Hoogdalem Ewoud J. Heijligers-Feijen Cornelia D. de Boer Albertus G. Verhoef J. Coos Breimer Douwe D. 《Pharmaceutical research》1989,6(1):91-95
The stability of the neuroleptic peptide des-enkephalin--endorphin (DEE; Org 5878) in the rectal lumen and the rectal bioavailability of DEE were investigated in conscious rats. Furthermore, the influence of peptidase inhibition, peptidase saturation, and absorption enhancement on DEE bio-availability were evaluated. Na2EDTA (0.25%, w/v) prolonged the degradation half-life of DEE in the ligated colon from 33 ± 7 to 93 ± 45 min. Without adjuvant, tritium-labeled DEE was absorbed from the rat rectum to a very low extent (0–4%). After administration of an excess of unlabeled DEE or with Na2EDTA, comparable results were obtained. The medium-chain glyceride preparation MGK markedly enhanced the rectal DEE bioavailability, up to 8–20%, which was further increased to 10–44% by coadministration of Na2EDTA. No substantial influence of varying the rectal delivery rate was observed. The results suggest that absorption enhancement and enzyme inhibition both are essential for effective increase of rectal peptide bioavailability. 相似文献
9.
目的:研究并比较结核分枝杆菌免疫保护性抗原DNA(Ag85A和ESAT-6)疫苗联合免疫,BCG免疫以及联合DNA疫苗初免-BCG加强免疫等不同的免疫策略,诱导免疫应答效果观察.方法:健康雌性BALB/c小鼠24只,随机分成PBS 阴性对照组,DNA初免-BCG异源加强组,DNA(Ag85A和ESAT-6)初免DNA同源加强组和BCG阳性对照组,共进行3次免疫,初免2次,最后1次加强,间隔2周1次.PBS组3次均注射PBS 溶液;DNA/BCG组以质粒DNA免疫2次,最后1次以BCG加强免疫;DNA/DNA组3次均以质粒DNA进行免疫;BCG组则注射PBS溶液2次后以BCG免疫.末次免疫后4、6、8周分别分离血清测定总IgG水平,同时分离小鼠脾细胞,体外经TB-PPD刺激后进行淋巴细胞增殖实验(XTT法)并测定脾细胞培养上清中IFN-γ和IL-4水平.结果:DNA/BCG、DNA/DNA、BCG组体外经TB-PPD刺激后均检测到特异性IgG抗体产生,3组平均效价为1:120、1:160、1:80,DNA/DNA组的抗体效价高于另外2组;小鼠脾细胞体外经TB-PPD刺激后,均能产生特异性淋巴细胞增殖并诱生较强的IFN-γ反应,其中DNA/BCG组IFN-γ的分泌水平高于DNA/DNA组和BCG组(P<0.05).结论:联合DNA疫苗初免-BCG加强的免疫策略能在小鼠体内诱导较强的特异性细胞免疫反应,产生高水平的IFN-γ. 相似文献
10.
结核分枝杆菌Ag85B基因疫苗免疫保护作用的初步研究 总被引:7,自引:1,他引:7
目的:研究编码结核分枝杆菌分泌蛋白Ag85B的基因疫苗pTB30m和pTB30s对免疫动物的保护作用。方法:以基因疫苗pTB30m和pTB30s肌注免疫BALB/c小鼠。免疫完成6 wk后,用5×105 CFU的MTB H37Rv毒株经小鼠尾静脉攻击感染。同时用尼龙毛柱分离基因免疫BALB/c小鼠的T细胞,并以5×106 T细胞/只小鼠过继免疫正常BALB/c小鼠,立即用105 CFU的MTB毒株经小鼠尾静脉攻击感染。4 wk后分别计数脾脏中的细菌负荷。结果:与生理盐水对照组相比较,pTB30m及pTB30s质粒免疫组BALB/c小鼠脾脏中的细菌负荷均减少,分别为0.645(log10 CFU,P<0.01)和0.839(log10CFU,P<0.001);而空质粒对照组小鼠脾脏中的细菌负荷减少较少。经质粒pTB30m和pTB30s免疫的BALB/c小鼠的T细胞,过继免疫的正常BALB/c小鼠,对攻击感染的MTB H37Rv毒株在脾脏中的增殖具有部分抑制作用。结论:pTB30s免疫的BALB/c小鼠,对MTB H37 Rv毒株攻击的保护作用优于pTB30m质粒免疫,有望进一步用于结核病的防治研究。 相似文献