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排序方式: 共有9801条查询结果,搜索用时 15 毫秒
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Adenovirus vaccine vectors expressing hepatitis B surface antigen: importance of regulatory elements in the adenovirus major late intron 总被引:10,自引:0,他引:10
B B Mason A R Davis B M Bhat M Chengalvala M D Lubeck G Zandle B Kostek S Cholodofsky S Dheer K Molnar-Kimber 《Virology》1990,177(2):452-461
Adenovirus types 4 and 7 are currently used as live oral vaccines for prevention of acute respiratory disease caused by these adenovirus serotypes. To investigate the concept of producing live recombinant vaccines using these serotypes, adenovirus types 4 (Ad4) and 7 (Ad7) were constructed that produce HBsAg upon infection of cell cultures. Ad4 recombinants were constructed that express HBsAg from a cassette inserted 135 bp from the right-hand terminus of the viral genome. The cassette contained the Ad4 major late promoter followed by leader 1 of the tripartite leader, the first intervening sequence between leaders 1 and 2, leaders 2 and 3, the HBsAg gene, and tandem polyadenylation signals from the Ad4 E3B and hexon genes. Using this same cassette, a series of Ad4 recombinants expressing HBsAg were constructed with deletions in the intervening sequence between leaders 1 and 2 to evaluate the contribution of the downstream control elements more precisely. Inclusion of regions located between +82 and +148 as well as +148 and +232 resulted in increases in expression levels of HBsAg in A549-infected cells by 22-fold and 44-fold, respectively, over the levels attained by an adenovirus recombinant retaining only sequences from +1 to +82, showing the importance of these elements in the activation of the major late promoter during the course of a natural Ad4 viral infection. Parallel increases were also observed in steady-state levels of cytoplasmic HBsAg-specific mRNA. When similar Ad7 recombinant viruses were constructed, these viruses also expressed 20-fold more HBsAg due to the presence of the intron. All Ad4 and Ad7 recombinants produced HBsAg particles containing gp27 and p24 which were secreted in the medium. When dogs were immunized intratracheally with one of these Ad7 recombinants, they seroconverted to both Ad7 and HBsAg to a high level. 相似文献
996.
D E Rizk T Raaschou N Mason B Berg 《Scandinavian journal of urology and nephrology》2001,35(4):305-309
OBJECTIVE: To investigate whether progesterone receptors are present in the mucosa of the urinary bladder of continent premenopausal women compared with continent postmenopausal women. MATERIALS AND METHODS: Fifty-seven biopsies from the mucosa of the trigone and lateral wall of the urinary bladder were examined by the avidin-biotin-peroxidase immunohistochemical technique for the presence of estrogen and progesterone receptors. The specimens were obtained at cystoscopy performed to investigate hematuria in 42 patients and neoplasia in 15. The study group (n = 29) comprised non-pregnant premenopausal women in the luteal phase of their menstrual cycle and the control group (n = 28) comprised postmenopausal women. None of the subjects had urinary incontinence or was taking medication with hormones. In no case did the primary lesion involve the specimen used for laboratory analysis. RESULTS: There was positive immunostaining with estrogen in 28 patients of the study group (96.5%) and 4 (14.4%) in the control group (p<0.0001). The 28 samples of the study group also showed positive immunostaining for progesterone receptors. There was positive immunostaining with progesterone in 18 samples (64.3%) of the control group (p<0.01). Fourteen samples (50%) of the control group thus showed positive immunostaining for progesterone but no evidence of positive immunostaining with estrogen. Immunostaining for estrogen and progesterone receptors was similar in trigonal and lateral wall samples. CONCLUSION: In continent pre- and post-menopausal women, a direct progestogenic effect on the mucosa of the urinary bladder seems likely in addition to estrogen. 相似文献
997.
J C Garbutt J P Mayo G M Gillette K Y Little G A Mason 《The American journal of psychiatry》1986,143(8):1038-1039
Four patients whose depressions were failing to respond to administration of tricyclic antidepressants were given separate trials of T3 and lithium. In all four cases, T3 failed to potentiate the antidepressant, whereas the lithium did. 相似文献
998.
一阶导数差示脉冲极谱法的建立及在药物分析中的应用 总被引:11,自引:0,他引:11
本文研究了一阶导数差示脉冲极谱法,并将其运用于扑尔敏、氟哌啶醇、维生素B6及其制剂的定量分析中。方法简便、快速、灵敏、结果准确。 相似文献
999.
S G Siris P C Bermanzohn S E Mason A Rifkin J M Alvir 《Progress in neuro-psychopharmacology & biological psychiatry》1992,16(4):539-547
1. Twenty-one schizophrenic or schizoaffective patients with histories of cannabis abuse and operationally-defined syndromes of post-psychotic depression completed a double-blind trial of adjunctive imipramine added to their on-going medication regimen of fluphenazine decanoate and benztropine. 2. The imipramine-treated patients had superior global outcome. 3. Subscales suggested that specific improvement occurred in imipramine-treated patients in the domain of depression-like features. 4. Psychotic symptomatology was not found to be exacerbated by the imipramine. 相似文献
1000.