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SUMMARY A case congenital dislocation of both knees and dislocation of the left hip in an infant whose mother had a chronic amniotic fluid leakage after mid-trimester amniocentesis. 相似文献
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高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
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石杉碱甲类似物的研究II.N-甲基吡啶酮石杉碱甲类似物的合成 总被引:4,自引:1,他引:3
石杉碱甲(1)是从中草药石杉属植物千层塔(Lycopodium serratum Thunb.)中分得的一种高效可逆的乙酰胆碱酯酶抑制剂,临床试验证实它对早老性痴呆症有显著疗效。本文报道N-甲基吡啶酮石杉碱甲类似物2和3的合成。2-甲氧基-5-甲氧羰基-11-亚甲基-5,9-甲撑环辛-7-烯并吡啶(9)在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮10,再用甲醇钠和碘甲烷甲基化得N-甲基吡啶酮11,11经碱性水解,Curtius重排和氨基的脱保护得N-甲基吡啶酮石杉碱甲类似物2。通过类似的途径从中间体2-甲氧基-5-甲氧羰基-7-甲基-11-酮-5,9-甲撑环辛-7-烯并吡啶(14)合成了类似物3。类似物2和3的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。 相似文献
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D L Weed 《American journal of public health》1995,85(7):914-918
Epidemiologists may benefit from the disciplines of history, philosophy of science, ethics, literature, and art. Within these disciplines lie answers to the questions of who we are, what is right, how to think, and when to act. Studying and participating in the humanities may also help epidemiologists focus their professional concerns on the humanity their methods serve. A parallel phenomenon in the clinical sciences--medical humanities--provides support for the approach (and some lessons). 相似文献
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Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
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Two calcium alginate-tipped wire swab specimens were obtained from 94 men and 106 women attending a sexually transmitted disease clinic. One swab was extracted thoroughly in 2-sucrose phosphate (2SP) immediately after obtaining the specimen. The second swab was returned to the Culturette cylinder (Marion Scientific, Kansas City, MO), and the ampule containing 2SP was crushed to moisten the swab during transport to the laboratory. After receipt in the laboratory, the swab was removed from the Culturette and extracted into 2 mL of 2SP. Both specimens then were cultured for the presence of Chlamydia trachomatis in McCoy's cells. C. trachomatis was recovered from 22 of 94 men (23.4%); 16 isolates came from both the Culturette swabs and vials. Six isolates were recovered exclusively from vials. Of 106 women, 13 (12.3%) were positive for C. trachomatis. In five instances, both vials and swabs yielded C. trachomatis; the organism was recovered eight times from vials but not swabs. The 2SP transport system for the 200 specimens was superior to the Culturettes for the recovery of C. trachomatis (P less than 0.01). Based on our results, swab specimens taken for laboratory diagnosis of C. trachomatis should be extracted immediately after collection in a vial containing 2SP. In addition, experiments comparing swab fibers indicated that there was a trend indicating higher inclusion counts with rayon-tipped swabs, compared with those containing calcium alginate. Because of possible toxicity of substances in calcium alginate fibers for several organisms causing sexually transmitted disease, rayon-tipped swabs or swabs of other composition should be used. 相似文献