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1.
目的由于卒中风险随着狭窄严重程度的增加而升高,因此认为颈内动脉(ICA)接近闭塞患者的卒中风险很高。在现有的随机试验中,还没有专门针对这种情况进行探讨,因此其处理尚存在争汶。方法:对相关文献进行系统评价。结果:对ICA接近闭塞患者的处理还存在争议:一些学者支持进行干预,而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难,因为这类研究需要大量的患者。尽管如此,基于目前的证据,似乎很难拒绝手术治疗。结论:由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议,因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据,大多数医疗中心选择手术治疗,但它相对干内科治疗的特粱尚右待证章. 相似文献
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Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
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A protein related to glycoprotein B of herpes simplex virus type 1 (HSV-1) produced in yeast (ygB-1) was purified with an immunoadsorbent. The molecular weight of the purified ygB-1 as determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis was 96,000. Mice injected twice with ygB-1 adsorbed to alum developed ELISA antibody to ygB-1, neutralizing antibody to HSV-1 and a lymphoproliferative response to ygB-1 and HSV-1. The immunized mice were protected against intraperitoneal and corneal challenge with HSV-1. Latent infection in the trigeminal ganglia after corneal challenge was also inhibited by immunization with ygB-1. Guinea-pigs pigs immunized with ygB-1 adsorbed to alum also developed ELISA antibody to to ygB-1 and neutralizing antibody to both types of HSV. After the second dose, strong lymphoproliferative responses were seen upon stimulation with HSV-2. Animals were protected against intravaginal challenge with HSV type 2. 相似文献
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An experimental technique designed to predict theophylline doses needed to attain therapeutic theophylline concentrations in 43 emergency department (ED) patients was compared with a standard conventional regimen in 46 ED patients. The experimental protocol utilized a computer-assisted dosage prediction program that incorporated baseline theophylline concentration rapidly obtained using a bedside assay. The standard protocol used conventional loading and infusion rates, as well as an estimate of time of last theophylline dose based on patient history. Plasma theophylline concentrations, estimated 1 and 6 hours after commencement of aminophylline therapy in each regimen, were compared. The experimental protocol was equally rapid but much more accurate in achieving targeted theophylline concentrations. Experimental dosage prediction was associated with a higher proportion of theophylline concentrations in the therapeutic range at 1 (81 percent vs 26 percent; p less than 0.001) and 6 hours (91 percent vs 37 percent; p less than 0.001). There was a trend toward fewer toxic concentrations recorded at 1 (0 percent vs 7 percent; p = 0.27) and 6 hours (0 percent vs 10 percent; p = 0.08). This protocol, which was performed quickly and without difficulty by residents in a busy hospital ED, offers an opportunity to improve the efficacy and decrease the toxicity of theophylline use in asthma emergencies. 相似文献
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Masako Tsunematsu Taketo Yamaji Daisuke Kozutsumi Rika Murakami Shigeki Kimura Kohsuke Kino 《Allergology international》2007,56(4):465-472
BACKGROUND: We are developing an immunotherapeutic peptide, Cry-consensus peptide, for Japanese cedar pollinosis. Cry-consensus peptide is a recombinant polypeptide containing six major human T-cell epitopes derived from both Cry j 1 and Cry j 2, two major allergens of Japanese cedar pollen. We examined the effect of Cry-consensus peptide on an allergic rhinitis model in B10.S mice, which have one common T-cell epitope in the Cry-consensus peptide. METHODS: B10.S mice were sensitized with Cry j 1/alum, then the Cry-consensus peptide was administered subcutaneously once a week for 5 weeks from the last sensitization. Histamine was dropped in both nostrils (10 microL per nostril) of each mouse on the day before continuous intranasal instillation of Cry j 1. Soon after the final challenge with Cry j 1, the mice were observed for 5 minutes for the resulting number of sneezes. In addition, serum levels of Cry j 1-specific IgE and IgG2a antibody, eosinophil infiltration in nasal tissue, and Cry j 1-specific cytokine production from splenocytes were evaluated. RESULTS: Cry-consensus peptide markedly inhibited Cry j 1-induced sneezes, eosinophil infiltration, and eosinophil peroxidase (EPO) activity in nasal tissue. Cry-consensus peptide inhibited the production of anti-Cry j 1 IgE (Th2-mediated) and significantly enhanced anti-Cry j 1 IgG2a (Th1-mediated). In cytokine production from splenocytes, Cry-consensus peptide significantly decreased in IL-4/IFN-gamma and IL-5/IFN-gamma ratios. CONCLUSIONS: It was concluded that Cry-consensus peptide effectively controlled allergic responses, which results from shifting from a Th2-dominated to a Th1-dominated immune response. 相似文献
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Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献