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101.
Expression of adenovirus type 2 DNA polymerase in insect cells infected with a recombinant baculovirus. 总被引:5,自引:0,他引:5 下载免费PDF全文
Sequences encoding adenovirus type 2 DNA polymerase were placed under control of the polyhedrin promoter and inserted into the baculovirus Autographa californica nuclear polyhedrosis virus by homologous recombination. Insect cells infected with the recombinant virus produced substantial amounts of the adenovirus type 2 DNA polymerase protein which was functional in both DNA polymerase and replication initiation reactions. Thus, the baculovirus expression system can provide active adenovirus type 2 DNA polymerase that is produced in quantities suitable for biochemical and structural analysis. 相似文献
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103.
D. Urquhart Hay 《BMJ (Clinical research ed.)》1973,3(5876):378-379
A 2·5-ml injection of 1/1,000 solution of euflavine given down each vas during vasectomy for sterilization will destroy all sperms within the semen and eliminate the necessity for examining two consecutive specimens of semen for azoospermia after the operation. No local inflammatory response has been observed in the seminal vesicles or prostate of 81 consecutive patients in whom the method has been used. 相似文献
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107.
Jawahar Mehta M.D. Paulette Mehta M.D. Don Hay Ph.D. 《Prostaglandins & other lipid mediators》1982,24(6):751-761
These experiments were conducted to determine the effects of dipyridemole on human platelet aggregation, platelet thromboxane A2 (TXA2) and human vessel wall prostacyclin (PGI2) generation. Dipyridamole in varying concentrations (5 to 50 μg/ml) had no direct effect on ADP-induced platelet aggregation in vitro, but it potentiated PGI2-induced platelet aggregation inhibition at these concentrations. Dipyridamole also inhibited arachidonic acid-induced platelet TXA2 generation at these concentrations. In continuously perfused umbilical vein segments, dipyridamole treatment resulted in stimulation of PGI2 release determined by bioassay and by measurement of its stable metabolite 6-keto-PGF1α. Minimum concentration of dipyridamole causing PGI2 release was 50 μg/ml. These in vitro studies suggest that anti-thrombotic effects of dipyridamole in man are mediated mainly by potentiation of PGI2 activity and to some extent by TXA2 suppression. Stimulation of PGI2 release by human vessels may not be seen in usual therapeutic concentrations. 相似文献
108.
To assess genotypic variability in nutrient supply of shoot branches, the distribution of 32P and 45Ca exported from a source nodal root (24-h uptake period) was measured within a genotype of a large-leaved (Kopu) and a small-leaved (Tahora) cultivar of Trifolium repens. Source-sink relationships of plants were modified by root severance, defoliation, and shade treatments. In control plants of both genotypes distribution of 32P and 45Ca closely followed the pathways that could be predicted from the known phyllotactic constraints on the vascular system. As such there was little allocation of radioisotopes (3.1% and 2.5% of exported 32P and 45Ca, respectively) from the source root to branches on the apposite side of the parent axis (far-side branches). However, genotypic differences in nutrient allocation were apparent, when treatments were imposed to alter intra-plant source-sink relationships. In the large-leaved genotype, the imposed treatments had minor effects on the allocation to far-side branches: whereas, in the small-leaved genotype, root severance and defoliation treatments increased lateral transport to far-side branches to 30% (32P) and 10% (45Ca) of exported radioisotopes. Genotypes with low (8–9) and high (12–13) numbers of vascular bundles were selected from within the large-leaved cultivar. Distribution of 32P was then measured after plants had been pre-treated by removal of all far-side roots two days prior to labelling. Genotypes with low vascular bundle number allocated 20% and those with high vascular bundle number 3.2% of exported 32P to far-side branches. It was concluded (1) that genotypic variation exists within T. repens for potential to alter intra-plant allocation of mineral nutrients, in response to treatments that modify source-sink relationships within plants; and (2) that this variation is correlated with differences among genotypes in the organisation of the vasculature of their stolons. 相似文献
109.
F. Wohlrab A.T. Jamieson J. Hay Rolf Mengel W. Guschlbauer 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1985,824(3):233-242
The effect of 2′-fluoro-2′-deoxycytidine (dCfl) on the growth of certain viruses of the herpes type was investigated. It is shown that the compound has considerable anti-viral activity against HSV-I, HSV-II, pseudorabies virus and equine abortion virus. It has an effect comparable to that of araC and is more efficient than br5dC, but less so than acyclovir. Experiments with thymidine kinase-negative strains of HSV-I indicated that dCfl was phosphorylated by the viral kinase, and its Km appears to be low and close to that of thymidine. Density gradient centrifugation enabled us to show that dCfl was incorporated into cellular and viral DNA and RNA. The cytotoxic activity of dCfl appears to be about 10-times smaller than that of araC. Removal of the nucleoside analog, washing and replacement with deoxycytidine reversed this effect, indicating rather a cytostatic than cytotoxic effect. 相似文献
110.
Mond JM Rodgers B Hay PJ Darby A Owen C Baune BT Kennedy RL 《Obesity (Silver Spring, Md.)》2007,15(11):2769-2779
Objective: The objective was to test the hypothesis that, in women, the association between obesity and impairment in psychosocial functioning is mediated by levels of weight and shape concerns and/or binge‐eating frequency. Research Methods and Procedures: Self‐report measures of eating disorder psychopathology, mental health functioning, subjective quality of life in the psychological and social domains, and days “out‐of‐role” associated with any (physical or mental) health problem, were completed by a community sample of women classified as obese (BMI ≥30 kg/m2, n = 639) or non‐obese (BMI <30 kg/m2, n = 4253). For each of the dependent measures, regression models were used to test the hypothesis of mediation by comparing the strength of the relationship between independent and dependent variables with and without inclusion of the putative mediator in the regression model. Results: On each measure, the conditions for perfect mediation were satisfied when weight or shape concerns acted as the putative mediator, indicating that there was no association between obesity and functional impairment after controlling for weight or shape concerns. In contrast, associations between obesity and impairment in psychosocial functioning remained highly significant when binge‐eating frequency was the putative mediator. Discussion: The findings suggest that in women, weight and shape concerns are an important mediator of the relationship between obesity and impairment in psychosocial functioning, whereas binge eating may not be of primary importance. A greater focus on body acceptance in obesity treatment may be indicated. 相似文献