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排序方式: 共有2371条查询结果,搜索用时 15 毫秒
951.
Daniel G Healy Patrick M Abou-Sleiman Niall Quinn Kourosh R Ahmadi Tetsutaro Ozawa Christoph Kamm Ullrich Wullner Wolfgang H Oertel Katrin Burk Erik Dupont Maria T Pellecchia Eduardo Tolosa Thomas Gasser Janice L Holton Tamas Revesz David B Goldstein Andrew J Lees Nicholas W Wood 《Movement disorders》2005,20(10):1338-1343
To date, the etiology of multiple system atrophy (MSA) has proved impenetrable. We investigated the role of genetic variation in the UCHL-1 gene in MSA and looked for the presence of disease susceptibility alleles. We determined the linkage disequilibrium structure of the gene and employed a haplotype tagging strategy with power to represent 95% of the haplotype diversity. This approach was performed using a set of tagging single nucleotide polymorphisms (SNPs) that can infer the allelic state of all the common SNPs in UCHL-1 with a high coefficient of determination. This strategy enabled us to scan across the gene and maintain the power to detect signal(s) from any potential functional variant(s). In 257 Gilman-probable or -definite MSA subjects and 1,536 controls, we did not detect a case-control frequency difference for either the tagged haplotypes or for individual tagging SNPs. This search included the S18Y variant of UCHL-1, which has been reported to be protective in Parkinson's disease. 相似文献
952.
Delayed hemolytic transfusion reaction in adult sickle‐cell disease: presentations,outcomes, and treatments of 99 referral center episodes
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Anoosha Habibi Armand Mekontso‐Dessap Constance Guillaud Marc Michel Keyvan Razazi Mehdi Khellaf Btissam Chami Dora Bachir Claire Rieux Giovanna Melica Bertrand Godeau Frédéric Galacteros Pablo Bartolucci France Pirenne 《American journal of hematology》2016,91(10):989-994
Delayed hemolytic transfusion reaction (DHTR) is one of the most feared complications of sickle‐cell disease (SCD). We retrospectively analyzed the clinical and biological features, treatments and outcomes of 99 DHTRs occurring in 69 referral center patients over 12 years. The first clinical signs appeared a median of 9.4 [IQR, 3–22] days after the triggering transfusion (TT). The most frequent DHTR‐related clinical manifestation was dark urine/hemoglobinuria (94%). Most patients (89%) had a painful vaso‐occlusive crisis and 50% developed a secondary acute chest syndrome (ACS). The median [IQR] hemoglobin‐concentration nadir was 5.5 [4.5–6.3] g/dL and LDH peak was 1335 [798–2086] IU/L. Overall mortality was 6%. None of the patients had been receiving chronic transfusions. Among these DHTRs, 61% were developed in previously immunized patients, 28% in patients with prior DHTR. Among Abs detected after the TT in 62% of the episodes, half are classically considered potentially harmful. No association could be established between clinical severity and immunohematological profile and/or the type and specificity of Abs detected after the TT. Management consisted of supportive care alone (53%) or with adjunctive measures (47%), including recombinant erythropoietin and sometimes rituximab and/or immunosuppressants. Additional transfusions were either ineffective or worsened hemolysis. In some cases, severe intravascular hemolysis can be likely responsible for the vascular reaction and high rates of ACS, pulmonary hypertension and (multi)organ failure. In conclusion, clinicians and patients must recognize early DHTR signs to avoid additional transfusions. For patients with a history of RBC immunization or DHTR, transfusion indications should be restricted. Am. J. Hematol. 91:989–994, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
953.
Jwaher Haji Alhaji 《Nutrients》2022,14(10)
Background: Diabetes is a global pandemic, especially in Arab countries. Aim: The goal of this study was to review the published studies that were conducted to determine the relationship between metformin treatment for type 2 diabetes mellitus (T2DM) and vitamin B12 deficiency and to identify possible complications in this relationship. Methods: I searched for all relevant studies published in English before 2020 on the PubMed and Web of Knowledge databases using the following terms: “metformin”, “vitamin B12”, “neuropathy”, “diabetes mellitus”, and Middle Eastern countries. Results: Eleven studies were included in this review which indicated an association between taking metformin and B12 deficiency in patients with T2DM in Arab countries. This B12 deficiency was found to be negatively associated with the dose and duration of metformin therapy. The physician’s knowledge of current ADA recommendations regarding supplementation with and screening of the B12 level for T2DM patients on metformin was also found to have an effect. Conclusion: Metformin therapy is associated with B12 deficiency among people with T2DM in Arabic countries. Thus, diabetes must be managed in compliance with current guidelines and recommendations, and B12 levels must be routinely monitored, particularly in those who have been long-term takers of metformin, to ensure the suitable management of diabetes and its complications. 相似文献
954.
Eik Schiegnitz Nina Hill Keyvan Sagheb Jochem Knig Kawe Sagheb Bilal Al-Nawas 《Acta stomatologica Croatica》2022,56(2):143
Objectivesthe aim of this clinical study was to compare clinical and radiological outcomes of short dental implants inserted in pristine bone to standard length implants inserted in combination with sinus floor elevation.Materials and methodsFor this clinical study, the clinical and radiological outcome of 126 short dental implants (84 patients), inserted in pristine bone were compared with 312 standard length implants (156 patients), placed in combination with maxillary sinus floor elevation procedures.ResultsThe short implant group (test group [TG]; mean follow-up (± standard deviation (SD) 56.6 ± 42.9 months) and the augmented group (control group [CG]; mean follow-up 41.6 ± 37.6 months) showed cumulative survival rates of 91.8% and 92.4%. Cumulative 5-year implant survival rates were 91.8% for the TG and 90.7% for the CG (p=0.421). Mean marginal bone loss was significantly higher in the CG than in the TG, with a mean MBL of 0.70 ± 0.72 mm in the TG and 0.96 ± 0.91 mm in the CG (p<0.001). A comparable and promising oral health-related quality of life (OHRQoL) was observed in the control and test groups.ConclusionsAfter over 3 years, short implants placed in the resorbed posterior maxilla obtained similar results to standard implants combined with maxillary sinus floor augmentation procedures. 相似文献
955.
Nabi Jomehzadeh Khadijeh Ahmadi Mozhdeh Amiri Bahmanshiri 《Journal of clinical laboratory analysis》2022,36(7)
BackgroundExtensive and inappropriate use of quinolones has led to growing resistance rates to these broad‐spectrum antibiotics. The present study purposed to investigate the prevalence of plasmid‐mediated quinolone resistance (PMQR) genes in Klebsiella pneumoniae clinical isolates.MethodNinety‐two non‐repetitive K. pneumoniae clinical isolates were confirmed by standard microbiological methods. Antibacterial susceptibility of isolates toward seven agents from the quinolone family was evaluated by the disc diffusion method. Ciprofloxacin minimum inhibitory concentrations (MICs) were determined using the standard agar dilution method. PCR amplification was used to detect the existence of PMQR genes in the studied isolates.ResultsIn the present study, significant quinolones'' resistance (40%) was observed in K. pneumoniae isolates, and most of the strains were resistant to nalidixic acid (94.6%) and ofloxacin (45.6%). MIC analysis showed 15 strains were resistant to 6–128 μg/ml of ciprofloxacin, and five were intermediately‐resistant. PMQR genes were detected in 88% of all isolates. Acc(6’)‐Ib‐cr was constituted half of the total PMQR genes detected among ciprofloxacin non‐susceptible isolates. Of 20 ciprofloxacin non‐susceptible isolates, 65% (n = 13) harbored multiple PMQR determinants, and 15 strains were determined as integron carriage.ConclusionThe findings of this study indicated considerable resistance against quinolones, which could be correlated with the extensive and inappropriate use of this class of antibiotics as empirical treatment. 相似文献
956.
木犀草素抑制人胃癌BGC-823细胞增殖作用的研究 总被引:2,自引:0,他引:2
目的研究木犀草素(Luteolin,Lu)对人胃癌BGC-823细胞增殖的体外抑制作用及其机制。方法 DPPH法测定Lu抗氧化活性;MTT法测定Lu对BGC-823细胞增殖的影响;流式细胞术检测细胞周期分布影响及诱导凋亡的作用;倒置显微镜下观察细胞形态学变化。结果 Lu清除自由基的能力与其浓度呈正相关(r2=0.979);5,10,20,40μmol/L的Lu作用48 h后对BGC-823细胞增殖抑制率分别为5.08%,7.09%,25.27%和53.77%,半数抑制浓度(IC50)为(37.88±5.81)μmol/L;Lu以浓度依赖性阻滞细胞周期在G2/M期,且S期细胞比例呈下降趋势。40μmol/L的Lu作用72 h后,BGC-823细胞凋亡率显著增高(P〈0.01);镜下观察发现经Lu处理后细胞固缩并伴随细胞膜破裂的现象。结论 Lu在体外对人胃癌BGC-823细胞增殖有明显的抑制作用,且呈剂量依赖性;抗氧化、改变细胞周期及诱导细胞凋亡是其抗肿瘤作用的机制。 相似文献
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