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101.
We have previously reported the purification of a 37-kd platelet- agglutinating protein (PAP p37) from the plasma of a patient with thrombotic thrombocytopenic purpura (TTP) that was shown to be present in a subset of TTP patients. The platelet agglutination induced by PAP p37 has been shown to be inhibited by IgG from normal human adults and the same TTP patient after recovery. To elucidate the mechanism of inhibition of IgG, the interaction between PAP p37 and IgG was studied. The complex formation was demonstrated by the binding of fluid-phase IgG from normal adults and the same TTP patient after recovery to adsorbed PAP by using an enzyme-linked immunosorbent assay. The binding was specific, concentration dependent, and saturable. IgG purified from a 5-month-old baby and the same TTP patient during active disease did not form complex with PAP p37. The IgG covalently cross-linked to Sepharose 4B bound 125I-PAP p37 but not 125I-fibrinogen. Sucrose density gradient ultracentrifugation of a mixture of 125I-PAP p37 and IgG also revealed the fluid-phase complex formation with a sedimentation value of 19S. Complexes of molecular weight ranging from 180,000 to over 350,000 daltons were also detected by molecular sieve chromatography. The IgG that was bound to PAP p37 conjugated to Sepharose 4B inhibited the agglutination of washed platelets induced by TTP plasma containing PAP p37, whereas the IgG that was not bound to PAP p37 did not have a significant inhibitory effect. The complex formation between PAP p37 and specific IgG is likely to account for the in vitro inhibition of TTP plasma-induced agglutination and, at least partly, the in vivo successful treatment with specific IgG-containing normal plasma. 相似文献
102.
103.
Determination of sibship in any two persons 总被引:4,自引:0,他引:4
BACKGROUND: Parentage testing laboratories may be asked to provide genetic evidence that two persons are or are not related, when no other relatives are available for study. Simple methods using autosomal, codominant, unlinked genetic systems can determine if two people are blood relatives (e.g., siblings). STUDY DESIGN AND METHODS: The odds ratios (full sibship index) of true sibling pairs were determined from two-child paternity cases and compared with regionally and racially matched control pairs of unrelated children. The sharing of two, one, or no alleles was observed in pairs of children at three independent, polymorphic VNTR (variable number of tandem repeat) sequences loci. The sibship index was calculated as (the chance that an observation would occur if two children were siblings) divided by (the chance that it would occur if the two were unrelated). Sibship indices and the frequencies of shared alleles were determined for 20 sibling pairs and 20 control pairs. RESULTS: Sibship index values were less than 1 in all 20 pairs of unrelated children. Sibship index values were greater than 100 in nine pairs of siblings (45%), between 10 and 100 in five pairs (25%), between 1 and 10 in four pairs (20%), and less than 1 in two pairs (10%). Siblings shared two alleles in 17 of 60 observations (28.3%); controls shared two alleles in 0 of 60 observations (0%). CONCLUSION: The sharing of one allele and the sharing of no alleles at a polymorphic locus of high heterozygosity provide limited information for and against sibship, respectively. The sharing of two alleles produces strong evidence favoring sibship. In a given case, the study of more than three polymorphic loci of high heterozygosity may be needed to develop the evidence that two people are siblings. The general logic and methods used for siblings apply to kinship analyses of other two-person pedigrees. 相似文献
104.
DIM Robinson BSc MB BS S. Lertsumitkul MB BS FA Billson FRACO FRACS † LP Robinson DO FRACO FRACS † 《Clinical & experimental ophthalmology》1993,21(2):79-85
A retrospective study of 179 eyes in 127 patients who underwent trabeculectomy at Sydney Eye Hospital under the supervision of two surgeons between 1977 and 1982 was carried out. Survival analysis by life table method shows cumulative two, five, and 10 year success rates to be 78%, 70%, and 67% respectively, with mean duration of intraocular pressure control (IOP<21 mmHg) being 88 months. Anti-glaucoma medication improved the long-term survival significantly (Hazard Ratio of 0.49 and P = 0.01) so that when the definition for failure is taken as IOP >20 mmHg while using medication, the two, five and 10 year success rates were 89%, 87% and 86% respectively. A rise in average intraocular pressure is seen between two weeks and three months after trabeculectomy. The improvement in long-term success rate with use of topical steroids was suggestive (Hazard Ratio of 0.69) but not conclusive (P = 0.21). No difference was found in survival comparing fornix versus limbal based flap technique. 相似文献
105.
特殊部位异位妊娠的临床分析 总被引:9,自引:0,他引:9
目的 探讨特殊部位(如子宫颈、输卵管间质部等)异位妊娠的早期诊断与预后的关系,及与重复异位妊娠相关的因素。方法 对特殊部位的异位妊娠及重复异位妊娠进行回顾性分析。结果 回顾分析201例异位妊娠,其中宫颈妊娠1.49%(3/201),输卵管间质部妊娠2.98%(6/201),卵巢妊娠1.00%(2/201),重复异位妊娠4.48%(9/201)。宫颈妊娠均B超早期诊断全部保守治疗成功,3例间质部妊娠、2例卵巢妊娠也经B超检查而早期发现及时处理,避免了大出血及休克的发生。重复异位妊娠中第一次异位妊娠前有剖宫产史者占77.78%。第二次异位妊娠腹腔内出血明显少于第一次。结论 特殊部位异位妊娠早期诊断预后较好,B超对其早期诊断有重要价值,重复异位妊娠与剖宫产的关系有待于进一步探讨。 相似文献
106.
Shana E McCormack Alessandra Chesi Jonathan A Mitchell Sani M Roy Diana L Cousminer Heidi J Kalkwarf Joan M Lappe Vicente Gilsanz Sharon E Oberfield John A Shepherd Soroosh Mahboubi Karen K Winer Andrea Kelly Struan FA Grant Babette S Zemel 《Journal of bone and mineral research》2017,32(1):115-124
More rapid skeletal maturation in African‐American (AA) children is recognized and generally attributed to an increased prevalence of obesity. The objective of the present study was to evaluate the effects of population ancestry on relative skeletal maturation in healthy, non‐obese children and adolescents, accounting for body composition and sexual maturation. To do this, we leveraged a multiethnic, mixed‐longitudinal study with annual assessments for up to 7 years (The Bone Mineral Density in Childhood Study and its ancillary cohort) conducted at five US clinical centers. Participants included 1592 children, skeletally immature (45% females, 19% AA) who were aged 5 to 17 years at study entry. The primary outcome measure was relative skeletal maturation as assessed by hand‐wrist radiograph. Additional covariates measured included anthropometrics, body composition by dual‐energy X‐ray absorptiometry (DXA), and Tanner stage of sexual maturation. Using mixed effects longitudinal models, without covariates, advancement in relative skeletal maturation was noted in self‐reported AA girls (~0.33 years, p < 0.001) and boys (~0.43 years, p < 0.001). Boys and girls of all ancestry groups showed independent positive associations of height, lean mass, fat mass, and puberty with relative skeletal maturation. The effect of ancestry was attenuated but persistent after accounting for covariates: for girls, 0.19 years (ancestry by self‐report, p = 0.02) or 0.29 years (ancestry by admixture, p = 0.004); and for boys, 0.20 years (ancestry by self‐report, p = 0.004), or 0.29 years (ancestry by admixture, p = 0.004). In summary, we conclude that advancement in relative skeletal maturation was associated with AA ancestry in healthy, non‐obese children, independent of growth, body composition, and puberty. Further research into the mechanisms underlying this observation may provide insights into the regulation of skeletal maturation. © 2016 American Society for Bone and Mineral Research. 相似文献
107.
陆政日|法宪恩|王宏山 《中国普通外科杂志》2017,26(12):1555-1561
目的:探讨外科手术治疗老年Stanford A型急性主动脉夹层(AAD)的近远期疗效。方法:回顾性分析2008年6月—2017年3月郑州大学第二附属医院心血管外科应用手术治疗的196例Stanford A型AAD患者资料,患者均采用全麻、深低温停循环加单侧选择性脑灌注技术进行外科手术治疗,其中33例患者年龄≥60岁(老年组),163例患者年龄60岁(年轻组),比较两组患者的临床资料和预后情况。结果:与年轻组比较,老年组男性患者比例低(45.5%vs.73.0%,P=0.000),De Bakey II型主动脉夹层发病率高(21.2%vs.6.7%,P=0.009);升主动脉置换+全弓置换+象鼻支架术应用比例低于年轻组(9.1%vs.28.2%,P=0.021)升主动脉置换+全弓置换+象鼻支架术应用比例减少(9.1%vs.28.2%,P=0.021),但单纯升主动脉置换比例增加(21.2%vs.2.5%,P=0.000),平均体外循环时间、主动脉阻断时间、手术时间均缩短(215.70 min vs.252.98 min,P=0.000;121.12 min vs.134.00 min,P=0.008;489.15 min vs.533.52 min,P=0.004);术后ICU停留时间延长(235.27 h vs.163.55 h,P=0.011),术后肾功能不全(21.2%vs.6.7%,P=0.009)、感染发生率(30.3%vs.9.8%,P=0.002)升高;术后生存率差异无统计学意义(P=0.1466)。全组病例分析显示,体外循环时间是AAD患者手术后院内死亡的危险因素(OR=0.987,95%CI=0.977~0.997,P=0.011),而年龄(OR=1.790,95%CI=0.651~4.921,P=0.259)与其他因素并非手术后院内死亡的危险因素。结论:对于老年AAD患者,根据夹层累及范围选择恰当的手术方式可以取得较满意的预后,术中尽可能缩短体外循环时间有助于提高手术疗效。 相似文献
108.
目的 探讨动脉瘤性蛛网膜下腔出血(SAH)患者迟发性脑血管痉挛(DCVs)的临床影响因素. 方法 回顾性分析南方医科大学珠江医院神经外科自2005年1月至2008年12月收治的74例动脉瘤性SAH患者的临床资料,判定DCVS,统计分析其影响因素. 结果年龄、出血次数、吸烟史、Hunt-Hess分级、Fisher分级、白细胞计数峰值与DCVS的发生具有明显相关性,其中年龄、出血次数、Hunt-Hess分级、Fisher分级是DCVS发生的独立影响因素. 结论 低年龄、出血2次以上及Hunt-Hess分级或Fisher分级Ⅲ级以上患者更易发生DCVS,临床上对此类患者应加强监测、及早发现和处理. 相似文献
109.
异体软组织修复材料在口腔颌面部缺损中的应用 总被引:15,自引:1,他引:15
目的 探讨异体软组织修复材料(异体脱细胞真皮基住)在口腔颌面外科应用的可行性。方法 选择口腔粘膜组织缺损患者46例,在创面上采用异体脱细胞真皮基质覆盖,并对修复后创面情况和组织病理进行观察。结果 所有口腔粘膜创面愈合良好,无1例出现排斥反应。经4~6月后组织学观察,异体脱细胞真皮基质处所生成的组织与正常粘膜组织不易区分。结论 异体脱细胞真皮基质可以作为口腔粘膜缺损的修复材料推广使用。 相似文献
110.
Murine leukemia inhibitory factor enhances retroviral-vector infection efficiency of hematopoietic progenitors 总被引:5,自引:0,他引:5
Fletcher FA; Williams DE; Maliszewski C; Anderson D; Rives M; Belmont JW 《Blood》1990,76(6):1098-1103
We have investigated the in vitro effects of the cytokine leukemia inhibitory factor (LIF) on normal murine hematopoietic progenitors by measuring recovery and retroviral vector infection efficiency of 13-day posttransplant, spleen-colony-forming cell (CFU-S 13) in short-term culture. Up to a twofold increase in CFU-S13 recovery was observed, from 9.7 x 10(-5) cells in untreated controls to 17.8 to 19.5 x 10(-5) cells, depending on the concentration of LIF. Histologic analysis of spleen colonies from control and LIF-treated marrows demonstrated that there was no detectable alteration in the differentiative potential of CFU-S13. The efficiency of CFU-S13 infection was increased from 15% in untreated controls to 84% to 91% in LIF-treated marrows. Analysis of proviral integration sites in spleen colonies indicated that some CFU- S13 precursors were infected in the LIF-treated marrows. 相似文献