简介:【摘要】 竖井多绳摩擦提升机更换首绳是矿山机电专业大型施工项目,其技术含量高,安全风险大,施工工艺复杂。针对赤峰柴矿提升系统的工况,介绍一种“以旧带新”的首绳更换工艺方法及安全措施,该工艺能极大的减轻换绳工作强度,缩短换绳时间,降低安全风险,取得较好经济效益和社会效益。
简介:AbstractBackground:The elimination of Plasmodium vivax malaria requires 8-aminoquinolines, which are contraindicated in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency due to the risk of acute haemolytic anaemia. Several point-of-care devices have been developed to detect G6PD deficiency. The objective of the present study was to evaluate the performance of two of these devices against G6PD genotypes in Mauritania.Methods:Outpatients were screened for G6PD deficiency using CareStart™ rapid diagnostic test (RDT) and CareStart™ G6PD biosensor in Nouakchott, Mauritania, in 2019-2020. African-type and Mediterranean-type G6PD genotypes commonly observed in Africa were determined by polymerase chain reaction-restriction fragment length polymorphism and sequencing. Qualitative variables were compared using Fisher’s exact test.Results:Of 323 patients (74 males and 249 females), 5 males and 2 homozygous females had the African-type A-genotype: A-(202) in 3 males and 2 females and G6PD A-(968) in 2 males. Among heterozygous females, 13 carried G6PD A-(202), 12 G6PD A-(968), and 3 G6PD A-(542) variants. None had the Mediterranean-type G6PD genotype. Eight had a positive G6PD RDT result, including all 7 hemizygous males and homozygous females with A- or A-A- (0.12 to 2.34 IU/g haemoglobin, according to G6PD biosensor), but RDT performed poorly (sensitivity, 11.1% at the cutoff level of < 30%) and yielded many false negative tests. Thirty-seven (50.0%) males and 141 (56.6%) females were anaemic. The adjusted median values of G6PD activity were 5.72 and 5.34 IU/g haemoglobin in non-anaemic males (n = 35) and non-anaemic males and females (n = 130) with normal G6PD genotypes using G6PD biosensor, respectively. Based on the adjusted median of 5.34 IU/g haemoglobin, the performance of G6PD biosensor against genotyping was as follows: at 30% cut-off, the sensitivity and specificity were 85.7% and 91.7%, respectively, and at 80% cut-off, the sensitivity was 100% while the specificity was 64.9%.Conclusions:Although this pilot study supports the utility of biosensor to screen for G6PD deficiency in patients, further investigation in parallel with spectrophotometry is required to promote and validate a more extensive use of this point-of-care device in areas where P. vivax is highly prevalent in Mauritania.
简介:摘要 本文主要介绍通过生产实践与工艺试验相结合的方法,对机体预埋钢管的工艺进行改进,解决钢管在浇铸过程中产生的弯曲、熔穿,内壁粘砂、结合面缝隙等问题。对此类产品工艺方法提出总体思路,并且在生产实践中得以验证和推广,同时通过大量生产实践,掌握机体铸管生产的设计规律。
简介:摘要目的总结Dent病患儿的临床特征、基因检测及用药后的疗效。方法选取2014年1月至2019年3月在广州市妇女儿童医疗中心诊断为Dent病的患儿6例,总结6例患儿病史、临床表现、实验室结果、基因检测结果及用药后尿蛋白、尿钙及肾功能水平。结果6例均为男童,发病年龄1~9岁,随访6个月~4年。6例患儿均有低分子量蛋白尿,其中仅2例尿蛋白电泳显示低分子量蛋白尿比例>50%;肾活检均合并肾小球病变;5例患儿有高钙尿症;镜下血尿5例;佝偻病2例;均无肾脏钙质沉着及低磷血症。基因检测显示,CLCN5突变5例,其中p.C160Yfs*49和p.G523D为首次报道;OCRL1突变1例。患儿采用氢氯噻嗪联合血管紧张素转化酶抑制剂(ACEI)联合治疗后,24 h尿钙定量较治疗前明显下降[0.40(0.24,0.43) mmol/kg比0.12(0.11,0.14) mmol/kg,U=2.00,P<0.01],总尿蛋白定量无明显减少[77.09 (62.41,88.01) mg/kg比80.33(66.03,92.52) mg/kg,U=12.00,P>0.05]。结论Dent病主要表现为低分子量蛋白尿,部分可不伴高钙尿症,基因检测有助于明确疾病分型,ACEI及氢氯噻嗪治疗后患儿尿钙降低,但尿蛋白程度无缓解。
简介:摘要:采用L-丙氨酸、草酸、乙醇同步酯化酰化制得N-乙氧草酰-L-丙氨酸乙酯,再经环合、水解、萃取、蒸馏制得4-甲基-5-乙氧基噁唑酯,经皂化反应,脱羧、蒸馏制得4-甲基-5-乙氧基噁唑;最后与2-正丙基-1,3-二氧-5-环庚烯经Diels-Alder反应制得维生素B6,总收率61.2%,(按照4-甲基-5-乙氧基噁唑计算,重量收率98.3%)此法成本低,操作简单,适应于工业化大生产。