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21.
Bloodstream forms of Trypanosoma brucei that were infective for mammals, when grown in vitro at 37 C for 29 days or 25 months had amounts of variant surface glycoprotein similar to the amounts from bloodstream forms isolated from infected rat blood. The amounts were measured by competition radioimmunoassays for both unique and cross-reacting determinants and the results were the same, providing evidence that a single type of variant surface glycoprotein was measured. Neither radioimmunoassay detected determinants of variant surface glycoproteins in trypanosomes transformed by culturing at 27 C to insect forms not infective for mammals.  相似文献   
22.
Genetic polymorphism is found among the PIF (parotid isoelectric focusing variant) salivary proteins after separation by prolonged isoelectric focusing in pH 3.5–5.2 urea polyacrylamide slab gels subsequently stained for protein. Two PIF proteins are either present (PIF +) or absent (PIF –) from all salivas. The phenotypes are determined by autosomal inheritance of two alleles, PIF + and PIF . Gene frequencies in randomly collected samples show marked racial differences: among 148 whites, PIF + is 0.66 and PIF is 0.34; among 90 blacks, PIF + is 0.35 and PIF is 0.65; among 78 Chinese, PIF + is 0.56 and PIF is 0.44. Studies in 41 families including 129 children support the interpretation of control of PIF by a single autosomal locus. In 8 PIF+ × PIF– matings, there were 8 PIF– (6.34 expected) children. In 33 PIF+ × PIF+ matings, there were 7 PIF– (6.70 expected) children. Linkage studies indicate that PIF is closely linked to the proline-rich protein (PPP) gene complex (e.g., for six families, lod score at =0.00 of PIF/G1 is 3.58). In 107 randomly collected samples from whites, PIF is strongly associated with Db (x 1 2 =20.02; P<0.0001) and Gl (x 1 2 =12.58; P=0.0005) but not with Pr, Ps, Pm, and Pa proteins. These data (probably reflecting genetic disequilibrium) suggest that PIF may be closer to Db and G1 than to other identified loci of the PPP gene complex. The PPP gene complex includes at least seven genes (and probably more) that produce many acidic and basic proline-rich proteins, constituting about two-thirds of parotid salivary proteins that are thought to have important functions at the tooth surfaces.This study was supported by a grant from the National Institutes of Dental Research (DEO 3658-15). Paper No. 2435 of the Laboratory of Genetics, University of Wisconsin, Madison, Wisconsin 53706.  相似文献   
23.
A variant of the baculovirus, Autographa californica nuclear polyhedrosis virus, has been isolated in Idaho during an epizootic disease in a field population of A. californica. Genotypic characterization indicates that the virus is distinct from variants previously characterized. Analysis of five clones, derived by plaque purification in cell culture, indicates relative homogeneity of the original virus isolate. Further exploration of the factors involved in natural genetic variability of baculoviruses is appropriate.  相似文献   
24.
A new inherited variant of carbonic anhydrase I (CA I), designated CA INagasaki 1 (CA INGS 1), was discovered during a survey of hemolysates from 5852 individuals from the cities of Hiroshima and Nagasaki in Japan. Analysis of the amino acid composition of a tryptic peptide from the CA INGS 1 variant indicated that a glutaminyl residue was substituted for an arginyl residue at position 76. Heat degradation studies showed that the CA INGS 1 variant was less stable than normal CA I. The CO2 hydrase and esterase activities of the normal and variant carbonic anhydrases I, as well as the relative amounts of the two enzymes in heterozygotes, were similar.This work was supported in part by Contract E(11-1)-1552 with the Energy Research and Development Administration, Washington, D.C. (to J. V. Neel), and by U.S. Public Health Service Grant GM-24681.  相似文献   
25.
目的:探讨急性呼吸窘迫综合征(ARDS)合并慢性气道疾病患者的临床特征及影响预后的因素。方法:167例ARDS患者根据并发症发生情况分为对照组(单纯性ARDS组,A组,n=39)及观察组(ARDS合并慢性气道疾,B组,n=49,C组,n=41,D组,n=38),比较各组患者一般情况、临床特征、生化指标、治疗方式及预后状况,通过logistic回归分析ARDS合并慢性气道疾病患者预后的影响因素。结果:观察组(B、C、D组)年龄、中性粒细胞、IL-6、IL-8、TNF-α、白蛋白、pro-BNP、乳酸、氧合指数、住院时间、住院费用与对照组(A组)比较差异有统计学意义,P0.05;128例ARDS合并慢性气道疾病患者中死亡76例,好转52例,病死率59.38%;单因素分析结果显示,观察组(B、C、D组)患者中临床结局好转患者与死亡患者比较,白细胞、淋巴细胞、CRP、TNF-α、IL-8、降钙素、肌酐、pro-BNP、氧合指数、住院费用、机械通气时间、抗生素数量差异有统计学意义,P0.05;通过多因素logistic回归分析发现肌酐是影响ARDS合并慢性气道疾病的潜在危险因素,氧合指数为保护因素,P0.05。结论:ARDS合并慢性气道疾病的能量代谢紊乱程度可能较单纯ARDS加重,且两者炎性特征不同。肌酐、氧合指数是影响ARDS合并慢性气道疾病的重要影响因素。  相似文献   
26.
目的:研究布地奈德福莫特罗粉吸入剂(ST)联合孟鲁斯特对支气管哮喘急性发作期(ASBA)患者肺功能及血清细胞因子水平的影响。方法:选择2015年2月到2017年8月在我院治疗的86例ASBA患者作为研究对象,根据随机数字表法将患者分成观察组(n=43)以及对照组(n=43),对照组予以ST治疗,观察组则在此基础上联合孟鲁司特治疗,两组均治疗3个月,对比两组患者治疗前及治疗3个月后的肺功能、细胞因子水平、咳嗽评分、St·George's呼吸疾病问卷(SGRQ)以及用药安全性。结果:治疗后两组患者的第1秒的用力呼气容积(FEV1)、用力肺活量(FVC)及FEV1/FVC均较治疗前升高,且观察组高于对照组(P0.05)。治疗后两组患者的白细胞介素-4(IL-4)、白细胞介素-5(IL-5)、γ-干扰素(INF-γ)及肿瘤坏死因子-α(TNF-α)水平均较治疗前降低,且观察组低于对照组(P0.05)。治疗后两组患者的咳嗽评分较治疗前升高,且观察组高于对照组(P0.05),而治疗后两组患者的SGRQ评分均较治疗前降低,且观察组低于对照组(P0.05)。观察组不良反应的总发生率为20.93%,与对照组的16.28%相比无统计学差异(P0.05)。结论:ASBA给予ST联合孟鲁司特治疗能够有效改善患者的症状,缓解机体炎症反映的同时还可有效改善患者肺功能和生活质量,其用药安全性较好。  相似文献   
27.
摘要 目的:探讨利多卡因经气管内给药和静脉给药对全麻苏醒期患者镇静镇痛效果、血流动力学和呛咳反应的影响。方法:选取2018年3月~2019年8月于我院在气管内全麻下完成泌尿外科、腹部外科并预计于术后可以迅速拔除气管导管的患者63例,上述患者根据随机数字表法分为A组(n=31)和B组(n=32),A组患者给予利多卡因静脉给药,B组患者给予利多卡因经气管内给药,比较两组患者苏醒时间、拔管时间、镇静镇痛效果、血流动力学及呛咳反应。结果:两组苏醒时间、拔管时间组间比较差异无统计学意义(P>0.05)。两组插管时、拔管时、拔管后10 min心率(HR)、收缩压(SBP)、舒张压(DBP)均呈先升高后降低趋势,且B组插管时、拔管时、拔管后10 min的HR、SBP、DBP均低于A组(P<0.05)。两组拔管时、拔管后10 min组内及组间镇静-躁动评分(SAS)比较差异无统计学意义(P>0.05);两组拔管后10 min疼痛视觉模拟量表(VAS)评分高于拔管时,但B组低于A组(P<0.05)。B组患者插管时、拔管时呛咳反应发生率均低于A组(P<0.05)。结论:与静脉给药相比,全麻苏醒期患者给予利多卡因经气管内给药,镇静镇痛效果确切,可减轻血流波动,降低插管时、拔管时呛咳反应发生率。  相似文献   
28.
The Rhesus (Rh) blood group system is the most important blood group system in hemolytic disease of the fetus and newborn (HDFN). In clinical transfusions, the D antigen in the Rh blood group system comes third, behind antigens A and B which from ABO blood group system. Over the past decade, molecular technologies have been used to investigate the RHD allele in different ethnic groups. This review first introduces the basic structure of RhD protein and coding genes, then focuses on D-negative, weak D, partial D, DEL, RhDnull variants reported in the Chinese population. To date, more than 460 RHD variants have been reported around the world, but less than 70 RHD variants have been reported in the Chinese population. Further research is needed to identify more RHD polymorphism and establish criteria for blood detection and transfusion guidelines for RHD variants. Only in this way can we better guarantee the safety of blood transfusion and prevent the occurrence of HDFN. With the accumulation of research and clinical data, we should be clearer which RHD variants are to be regarded as RhD negative and which need to be regarded as RhD positive.  相似文献   
29.
The discovery of rare genetic variants through next generation sequencing is a very challenging issue in the field of human genetics. We propose a novel region‐based statistical approach based on a Bayes Factor (BF) to assess evidence of association between a set of rare variants (RVs) located on the same genomic region and a disease outcome in the context of case‐control design. Marginal likelihoods are computed under the null and alternative hypotheses assuming a binomial distribution for the RV count in the region and a beta or mixture of Dirac and beta prior distribution for the probability of RV. We derive the theoretical null distribution of the BF under our prior setting and show that a Bayesian control of the false Discovery Rate can be obtained for genome‐wide inference. Informative priors are introduced using prior evidence of association from a Kolmogorov‐Smirnov test statistic. We use our simulation program, sim1000G, to generate RV data similar to the 1000 genomes sequencing project. Our simulation studies showed that the new BF statistic outperforms standard methods (SKAT, SKAT‐O, Burden test) in case‐control studies with moderate sample sizes and is equivalent to them under large sample size scenarios. Our real data application to a lung cancer case‐control study found enrichment for RVs in known and novel cancer genes. It also suggests that using the BF with informative prior improves the overall gene discovery compared to the BF with noninformative prior.  相似文献   
30.
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