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11.
Katherine A. Vittes Ph.D. Susan B. Sorenson Ph.D. 《The Journal of adolescent health》2006,39(6):929-932
In a survey of 5657 community-residing adolescents, those who said they could get a handgun in two days reported similar and those who said they could not get a handgun reported fewer risk behaviors and less violence perpetration and victimization than adolescents who have their own handgun. Adolescents who said they could get a handgun reported more exposure to and experience with firearms than those who said they could not get a handgun. Risk reduction efforts regarding adolescents should be expanded to include adolescents who say they can get a handgun. 相似文献
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进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
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The effects of carbamazepine on stuttering. 总被引:1,自引:0,他引:1
J E Harvey R Culatta J A Halikas J Sorenson M Luxenberg V Pearson 《The Journal of nervous and mental disease》1992,180(7):451-457
No pharmacological treatment protocol has proven generally useful for all patients who stutter. Various medications, behavior therapy, relaxation, suggestion, and social-based therapies have been used. For this drug treatment study, two groups of adult stutterers were followed in an 8-week open label protocol. All subjects had in the past received speech therapy; none had been treated previously with medication for stuttering. The first group (N = 12) received a maximum dose of 800 mg of carbamazepine; the second group (N = 8) received a maximum dose of 400 mg of carbamazepine. Each patient served as his or her own control. A series of systematic speech tests was given weekly to determine the variability of fluency for each subject. A statistically significant change occurred for a number of "expectancy to stutter" characteristics. Subjects felt that they stuttered less often while taking carbamazepine. Subjective effects began before medication and continued after patients discontinued the medication. Struggle characteristics also subjectively decreased. However, no objective improvement was found. No change was found in percentage of words stuttered, reading improvement, or improvement in spontaneous speech rate. Interrater reliability showed a correlation of .996. Three carbamazepine serum level therapeutic windows were inspected with negative results. Interestingly, naive listener ratings did show a statistically significant improvement on carbamazepine versus placebo. Future anecdotal reports of pharmacological improvement of stuttering should be subjected to rigorous objective testing before general acceptance. 相似文献
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Molecular analysis of the short arm of chromosome 3 in small-cell and non-small-cell carcinoma of the lung 总被引:23,自引:0,他引:23
H Brauch B Johnson J Hovis T Yano A Gazdar O S Pettengill S Graziano G D Sorenson B J Poiesz J Minna 《The New England journal of medicine》1987,317(18):1109-1113
Previous studies have suggested that the loss of DNA sequences on the short arm of chromosome 3 (3p) is associated with small-cell lung carcinoma. We therefore looked for loss of 3p alleles in tumor tissue from 42 patients with either small-cell or non-small-cell lung carcinoma. All 13 patients with small-cell lung carcinoma who were heterozygous for one or more alleles at 3p in normal tissue had the loss of at least one codominant allele in the tumor tissue. Cell lines of small-cell lung carcinoma from an additional eight patients were homozygous for 3p alleles; this result was significantly different from the predicted frequency of homozygosity. The tumor tissue studied included cell lines of small-cell lung carcinoma obtained from biopsy specimens, an autopsy sample, and an excised lymph node containing tumor cells. Loss of alleles at 3p was observed in tumor samples obtained before and after chemotherapy. Four of 15 evaluable patients with non-small-cell carcinoma of the lung had loss of 3p alleles. We conclude that loss of alleles at 3p is a change found consistently in small-cell lung carcinoma and occasionally in non-small-cell lung carcinoma. 相似文献
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Although permeation of capillary endothelia by horseradish peroxidase has been related to the presence of narrow channels between cells, junctions between endothelial cells in the aorta contain extensive regions that are occluded by apposition or fusion of the adjacent plasma membranes. Despite this, intravenously infused horseradish peroxidase rapidly appears within both the endothelial cell junctions and the microvesicles and caveoli. This suggests that the enzyme may arrive in the junctional space by some route other than passage between the endothelial cells. One possibility is vesicular transport from the lumen to the junctional cell surface. Alternatively, the occluded regions may represent only a partial permeability barrier, which either incompletely surrounds each cell in the manner of the maculae occludentes of epithelia, or leaves passages open between some cells while completely closing the perimeter of others. The aortic intima also differs from other vessel linings in having a reticular form of basement membrane. The structural role of this reticulum in supporting the endothelium remains undetermined as does its effect on premeability of the intima. 相似文献
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Expression of a gene encoding the major antigenic protein 2 homolog of ehrlichia chaffeensis and potential application for serodiagnosis 下载免费PDF全文
Alleman AR Barbet AF Bowie MV Sorenson HL Wong SJ Bélanger M 《Journal of clinical microbiology》2000,38(10):3705-3709
The major antigenic protein 2 (MAP2) homolog of Ehrlichia chaffeensis was cloned and expressed. The recombinant protein was characterized and tested in an enzyme-linked immunosorbent assay (ELISA) format for potential application in the serodiagnosis of human monocytic ehrlichiosis. The recombinant protein, which contained a C-terminal polyhistidine tag, had a molecular mass of approximately 26 kDa. The antigen was clearly identified by Western immunoblotting using antihistidine antibody. However, immune sera failed to react with the recombinant on immunoblots when the antigen was denatured by heat or reduced using beta-mercaptoethanol. The recombinant MAP2 (rMAP2) was used in an ELISA format with 60 blinded serum samples. Twenty of the serum samples were previously demonstrated to contain antibodies reactive with E. chaffeensis by indirect immunofluorescence assays (IFAs). The remaining 40 samples were seronegative. All samples negative by IFA were also found to be negative for antibodies against the rMAP2 of E. chaffeensis by using the ELISA. Only 1 of 20 IFA-positive samples tested negative in the rMAP2 ELISA. There was 100% agreement using IFA-negative samples and 95% agreement using IFA-positive samples, resulting in a 97.5% overall agreement between the two assays. These data suggest that the rMAP2 homolog of E. chaffeensis may have potential as a test antigen for the serodiagnosis of human monocytic ehrlichiosis. To our knowledge, this recombinant is unique because it is thus far the only E. chaffeensis recombinant antigen that has been shown to work in an ELISA format. 相似文献
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Guyer DR Yannuzzi LA Slakter JS Sorenson JA Orlock S 《Current opinion in ophthalmology》1993,4(3):3-6
The use of indocyanine-green videoangiography as an adjunctive technique to fluorescein angiography in the diagnosis of choroidal neovascularization has recently gained widespread attention. In January 1993, the first international symposium on indocyanine-green angiography was sponsored by the Manhattan Eye, Ear, and Throat Hospital. Approximately 300 retina specialists from all over the world convened at this meeting. Our current knowledge of indocyanine-green videoangiography is reviewed. 相似文献