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71.
Immunological assay for carbohydrate antigen 19-9 using an electrochemical immunosensor and antigen immobilization in titania sol-gel matrix 总被引:6,自引:0,他引:6
We describe a novel electrochemical immunosensor for carbohydrate antigen 19-9 (CA19-9) based on the immobilization of CA19-9 with titania sol-gel on a graphite electrode (GE) by vapor deposition. The CA19-9 membrane was characterized using scanning electron microscopy and proved to be chemically clean, porous and homogeneous. The incubation of the immunosensor in a solution containing horseradish peroxidase (HRP)-labeled CA19-9 antibody led to the binding of HRP-labeled antibody with the immobilized antigen. The immobilized HRP catalyzed the oxidation of catechol by H(2)O(2) and this provided a competitive method for the measurement of serum CA19-9. The response current decreased with increasing CA19-9 concentration in the incubation solution. The effects of pH, amount of HRP-labeled antibody, incubation time and temperature were explored to provide optimum analytical performance. Under optimal conditions, the current decrease of the immunosensor was proportional to CA19-9 concentrations in the range of 3-20 U/ml with a detection limit of 2.68 U/ml at a current decrease of 10%. The detection of CA19-9 in two serum samples obtained from clinically diagnosed patients with pancreatic carcinoma showed acceptable accuracy. The proposed immunosensor provides a new promising tool for the clinical immunoassay of CA19-9. 相似文献
72.
本文应用免疫细胞化学及NSE-ELISA方法观察了一氧化氮对体外培养脊髓和背根神经节神经元的存活及对活性的影响。结果表明:一氧化氮合酶抑制剂N-Arg组(100、200μmol/L)NSE免疫反应阳性神经元数目、面积(AF值)及活性(OD值)明显大于空白对照组(P<0.01)。而一氧化氮合酶底物L-Arg组(1mmol/L)神经元面积积分和活性则小于对照组(P<0.01)。L-Arg的细胞毒性作用可为N-Arg逆转。 相似文献
73.
腹膜透析治疗小儿先天性心脏病术后急性肾功能衰竭 总被引:5,自引:1,他引:4
目的:探讨腹膜透析(PD)对小儿先天性心脏病(先心病)术后急性肾功能衰竭(ARF)的治疗效果。方法:对36例先心病术后ARF行PD治疗患儿的临床资料作回顾性调查。结果:全组经PD治疗后的病死率为30.6%,其中单纯ARF的病死率12.5%,显著低于合并其他系统器官衰竭组的45%(P〈0.05)。PD3~30d内肾功能恢复,其中1~2d内血K^+恢复正常,2~5d内血碳酸氢根(HCO3^-)恢复正常,4~6d内血尿素氮下降49.2%,血肌酐下降42.6%。结论:对小儿先心病术后ARF及早进行PD具有较好的治疗效果。 相似文献
74.
Jonas Michel Wolf Lucas Michel Wolf Graziele Lima Bello Juçara Gasparetto Maccari Luiz Antonio Nasi 《Journal of medical virology》2023,95(1):e28366
Severe acute respiratorysyndrome coronavirus-2 (SARS-CoV-2) pandemic spread rapidly and this scenario is concerning worldwide, presenting more than 590 million coronavirus disease 2019 cases and 6.4 million deaths. The emergence of novel lineages carrying several mutations in the spike protein has raised additional public health concerns worldwide during the pandemic. The present study review and summarizes the temporal spreading and molecular evolution of SARS-CoV-2 clades and variants worldwide. The evaluation of these data is important for understanding the evolutionary histories of SARSCoV-2 lineages, allowing us to identify the origins of each lineage of this virus responsible for one of the biggest pandemics in history. A total of 2897 SARS-CoV-2 whole-genome sequences with available information from the country and sampling date (December 2019 to August 2022), were obtained and were evaluated by Bayesian approach. The results demonstrated that the SARS-CoV-2 the time to the most recent common ancestor (tMRCA) in Asia was 2019-12-26 (highest posterior density 95% [HPD95%]: 2019-12-18; 2019-12-29), in Oceania 2020-01-24 (HPD95%: 2020-01-15; 2020-01-30), in Africa 2020-02-27 (HPD95%: 2020-02-21; 2020-03-04), in Europe 2020-02-27 (HPD95%: 2020-02-20; 2020-03-06), in North America 2020-03-12 (HPD95%: 2020-03-05; 2020-03-18), and in South America 2020-03-15 (HPD95%: 2020-03-09; 2020-03-28). Between December 2019 and June 2020, 11 clades were detected (20I [Alpha] and 19A, 19B, 20B, 20C, 20A, 20D, 20E [EU1], 20F, 20H [Beta]). From July to December 2020, 4 clades were identified (20J [Gamma, V3], 21 C [Epsilon], 21D [Eta], and 21G [Lambda]). Between January and June 2021, 3 clades of the Delta variant were detected (21A, 21I, and 21J). Between July and December 2021, two variants were detected, Delta (21A, 21I, and 21J) and Omicron (21K, 21L, 22B, and 22C). Between January and June 2022, the Delta (21I and 21J) and Omicron (21K, 21L, and 22A) variants were detected. Finally, between July and August 2022, 3 clades of Omicron were detected (22B, 22C, and 22D). Clade 19A was first detected in the SARS-CoV-2 pandemic (Wuhan strain) with origin in 2019-12-16 (HPD95%: 2019-12-15; 2019-12-25); 20I (Alpha) in 2020-11-24 (HPD95%: 2020-11-15; 2021-12-02); 20H (Beta) in 2020-11-25 (HPD95%: 2020-11-13; 2020-11-29); 20J (Gamma) was 2020-12-21 (HPD95%: 2020-11-05; 2021-01-15); 21A (Delta) in 2020-09-20 (HPD95%: 2020-05-17; 2021-02-03); 21J (Delta) in 2021-02-26 (2020-11-02; 2021-04-24); 21M (Omicron) in 2021-01-25 (HPD95%: 2020-09-16; 2021-08-08); 21K (Omicron) in 2021-07-30 (HPD95%: 2021-05-30; 2021-10-19); 21L (Omicron) in 2021-10-03 (HPD95%: 2021-04-16; 2021-12-23); 22B (Omicron) in 2022-01-25 (HPD95%: 2022-01-10; 2022-02-05); 21L in 2021-12-20 (HPD95%: 2021-05-16; 2021-12-31). Currently, the Omicron variant predominates worldwide, with the 21L clade branching into 3 (22A, 22B, and 22C). Phylogeographic data showed that Alpha variant originated in the United Kingdom, Beta in South Africa, Gamma in Brazil, Delta in India, Omicron in South Africa, Mu in Colombia, Epsilon in the United States of America, and Lambda in Peru. The COVID-19 pandemic has had a significant impact on global health worldwide and the present study provides an overview of the molecular evolution of SARS-CoV-2 lineage clades (from the Wuhan strain to the currently circulating lineages of the Omicron). 相似文献
75.
76.
Abdullahi Idris Nasir Lozano Carmen Juárez-Fernández Guillermo Höfle Ursula Simón Carmen Rueda Silvia Martínez Angela Álvarez-Martínez Sandra Eguizábal Paula Martínez-Cámara Beatriz Zarazaga Myriam Torres Carmen 《European journal of clinical microbiology & infectious diseases》2023,42(5):569-581
European Journal of Clinical Microbiology & Infectious Diseases - This study determined the carriage rates and antimicrobial resistance (AMR) genes of enterococci from... 相似文献
77.
目的观察中剂量特尔立(rhGM-CSF)对恶性肿瘤化疗后白细胞减少的防治作用.方法采用自身对照,化疗过程中白细胞降至正常值(4.0×109/L)以下时入组,并作为对照周期.其后的化疗周期中末次给药48小时后皮下注射rhGM-CSF(150ug/(次.天).结果 rhGM-CSF能明显减轻化疗后白细胞下降的程度,缩短白细胞在正常值以下的持续时间及恢复到正常值以上的时间,对血小板的变化影响不大,毒副反应轻微.结论使用特尔立(rhGM-CSF)安全、有效,可作为肿瘤化疗有价值的辅助药物. 相似文献
78.
目的:探索晚期肺腺癌患者化疗疗效和对化疗的耐受性,化疗后生活质量变化和生存期。材料与方法:回顾分析1992-11~1995-04,经病理确诊为肺腺癌。按UICC分期为Ⅲb、Ⅳ期,Kamofsky评分≥60,连续完成2程以上的以铂类药物为主的联合化疗方案治疗患者。结果:化疗有效率3.1%,化疗后Kamofskv评分不变者43.8%,升高40.6%。下降≥10分15.6%,Ⅲb期中位生存期13月,Ⅳ期10月。结论:全身状况较好无化疗禁忌证的晚期肺腺癌患者,给予适当的联合化疗可使部分患者病情改善,生活质量提高。 相似文献
79.
80.
Bilateral macular hemorrhage after laser in situ keratomileusis 总被引:2,自引:0,他引:2
José Domingo Luna Victor Eduardo Reviglio Claudio Patricio Juárez 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1999,237(7):611-613
· Background: This is the first report of a bilateral submacular hemorrhage after LASIK surgery in an extreme myo pic patient.
A 31-year-old man underwent bilateral surgery for correction of –16.75+0.75×70° and –16.50+0.50×55°. · Methods: Case report. ·
Results: One day after surgery the patient’s uncorrected visual acuity was in the 20/50 range OU and by 17 days after surgery
his visual acuity had declined to 20/200 range. Fundus examination showed multifocal subretinal macular and posterior pole
hemorrhages. Fluorescein angiography showed some macular lesions compatible with lacquer cracks. · Conclusions: Preoperative
and postoperative fundus examination is important to detect this phenomenon. Patients should be informed of this rare complication.
Received: 2 June 1998 Revised version received: 16 November 1998 Accepted: 17 November 1998 相似文献