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排序方式: 共有523条查询结果,搜索用时 15 毫秒
511.
Mohinder R. Vindhyal Paul Ndunda Sinan Khayyat Venkata Subbarao Boppana Zaher Fanari 《Cardiovascular Revascularization Medicine》2019,20(10):852-857
BackgroundDialysis is associated with higher rate of aortic valve calcification and higher cardiovascular mortality. Transcatheter aortic valve replacement (TAVR) is an established alternative for surgical aortic valve replacement (SAVR) in patients with higher and intermediate co-morbidities including dialysis.MethodsTwo independent investigators systematically searched Medline, Cochrane, and Web of Science. The ROBINS-I tool was used to analyze and assess the bias from the selected studies.ResultsThe search resulted in 4 observational studies with a total of 966 patients. TAVR in dialysis patients was associated with no significant difference in in-hospital mortality [8.1% vs 10.3%; OR (95% CI) 0.74 (0.35, 1.60), I2 = 50%, P = 0.45], risk-of-strokes at 30 days [2% vs 4.4%; OR (95% CI) 0.49 (0.22, 1.09), I2 = 0%, P = 0.08], vascular complications [12.7% vs 13.2%; OR (95% CI) 0.96 (0.55, 1.67), I2 = 0%, P = 0.89], need of blood transfusion [43.1% vs 66.4%; OR (95% CI) 0.27 (0.05, 1.39), I2 = 89%, P = 0.12], or bleeding risk [5.6% vs 6.8%; OR (95% CI) 0.91 (0.18, 4.64), I2 = 5%, P = 0.91] when compared to SAVR. TAVR was associated with significantly shorter length of stay [8.5 days vs 14.2 days; mean difference (95% CI) ?5.89 (?9.13, ?2.64), I2 = 76%, P < 0.0001] and higher pacemaker implantation [11.4% vs 6.8%; OR (95% CI) 1.74 (1.07, 2.81), I2 = 5%, P = 0.02].ConclusionTAVR outcomes were comparable to SAVR but had a significantly shorter length of stay and a higher pacemaker implantation rate in dialysis patients. 相似文献
512.
Jeddi R Ghédira H Ben Amor R Turki A Kacem K Ben Abdennebi Y Ben Lakhal R Aissaoui L Ben Abid H Bel Hadjali Z Meddeb B 《Hematology (Amsterdam, Netherlands)》2011,16(3):160-165
Pseudomonas is a clinically significant and opportunist pathogen, usually associated in causing high mortality nosocomial infections. The aim of this study was to determine the risk factors associated with septic shock in patients diagnosed with hematologic malignancies and Pseudomonas infections. A total of 80 Pseudomonas isolates (77 Pseudomonas aeruginosa) were collected from 66 patients aged 2-64 years: 52 with acute leukemia (79%), 7 with lymphoma (10.5%), and 7 with other hematologic disorders (10.5%), between 2001 and 2009. The median age of the patients was 30 years. Isolates were collected mostly from bloodstreams (45%) and skin lesions (31.5%). The median time for microbiologic documentation was 8 days (range 0-35 days) from onset of neutropenia. At least 11 patients (16.6%) had recurrent (≥2) infections. The clinical symptoms observed were skin lesions (34%), diarrhea (20%), isolated fever (18%), and respiratory symptoms (14%). The isolates tested were found resistant to piperacillin/tazobactam (43%), ceftazidime (31%), imipenem-cilastatin (26%), ciprofloxacin (25%), and amikacin (26%). Septic shock occurred in 16.2% of episodes (13/80). Crude mortality due to septic shock occurred in 19.6% of patients (13/66). The median time for response to antibiotic therapy in the remaining 80.4% of patients (53/66) was 2.5 days. Univariate analysis revealed that factors associated with septic shock were: fever for ≥3 days in patients on antibiotic therapy (P = 0.019), serum lactate >5 mmol (P = 0.05), hemoglobin level <50 g/l (P = 0.042), hypoproteinemia <50 g/l (P = 0.01), procalcitonin >10 ng/ml (P = 0.031), and hypophosphatemia (P = 0.001). Multivariate analysis revealed that hypophosphatemia (P = 0.018), hypoproteinemia (P = 0.028), and high serum lactate (P = 0.012) are significant factors, independently associated with increased risk of septic shock in patients with hematologic malignancies and Pseudomonas infections. 相似文献
513.
VEGF signaling often represents a critical rate-limiting step in physiological angiogenesis. The VEGF family comprises seven secreted glycoproteins that are designated VEGF-A, VEGF-B, VEGF-C, VEGF-D, VEGF-E, placental growth factor (PlGF) and VEGF-F. The VEGF family members bind their cognate receptors. The receptors identified so far are designated VEGFR-1, VEGFR-2, VEGFR-3 and the neuropilins (NP-1 and NP-2). We review in this article the biology of the VEGF ligands and the receptors. 相似文献
514.
A Vassall S Bagdadi H Bashour H Zaher P V Maaren 《The international journal of tuberculosis and lung disease》2002,6(12):1083-1090
SETTING: The National Tuberculosis Programmes in Egypt and Syria. OBJECTIVES: To calculate the costs and effectiveness of alternative ways of implementing TB control in Egypt and Syria, in order to illustrate the factors influencing the cost-effectiveness of TB treatment in middle-income countries. DESIGN: We compared the costs and cure rates in Egypt and Syria of the World Health Organization recommended directly observed treatment, short-course (DOTS) strategy and alternative strategies. The study included costs both to the health services and to the patient. RESULTS: In Egypt and Syria, the cost-effectiveness of DOTS implemented through the primary health care (PHC) system was respectively $258 and $243 per patient cured. This compares to a cost per patient cured of $297 (Egypt) and $693 (Syria) for alternative strategies implemented through specialist clinics. In Egypt, when DOTS is implemented through specialist chest clinics it costs $585 per patient cured. Hospitalisation costs either $1490, $1621 or $1699 per patient cured, depending on treatment delivery in the continuation phase. CONCLUSION: This study demonstrates that the move towards DOTS integrated at the PHC level has substantially improved the effectiveness of TB treatment in Egypt and Syria, without substantially increasing costs. An analysis of the different costs and effectiveness of the variety of TB treatment strategies has enabled both National Tuberculosis Programmes to expand DOTS and implement it in a way that takes into account limited resources and local health systems. 相似文献
515.
Abuzenadah AM Hussein IM Damanhouri GA A-Sayes FM Gari MA Chaudhary AG Zaher GF Al-Attas A Al-Qahtani MH 《Hemoglobin》2011,35(4):346-357
This study aimed at the identification of the spectrum of mutations in patients with β-thalassemia (β-thal) in the western province of Saudi Arabia. Screening for the mutations was done using the polymerase chain reaction-amplification refractory mutation system (PCR-ARMS) technique to test for 12 mutations, and direct automated DNA sequencing for the unknown samples. The study included 172 patients; of these 15 patients had sickle cell anemia and one Hb S [β6(A3)Glu→Val, GAG>GTG]/β-thal. A total of 23 mutations were identified to cause the disease in the western area. Seven common mutations were responsible for the β-thal alleles in 78% of patients and could be detected by the ARMS technique: IVS-II-1 (G>A), IVS-I-110 (G>A), IVS-I-5 (G>C), codon 39 (C>T), codon 26 (G>A) [Hb E or β26(B8)Glu→Lys, GAG>AAG], frameshift codons (FSC) 8/9 (+G), and IVS-I-1 (G>A). DNA sequencing of uncharacterized alleles detected eight less common mutations: FSC 41/42 (-TCTT), IVS-I 25 bp deletion, codon 37 (G>A), FSC 44 (-C), Cap site +1 (A>C), IVS-I-6 (T>C), FSC 5 (-CT) and IVS-I-1 (G>T), and eight rare mutations: -87 (C>G), initiation codon -1 (T>G), codon 15 (G>A), FSC 16 (-C), FSC 20/21 (+G), codon 27 (G>A), IVS-I-130 (G>C) and IVS-II-837 (A>C). Four alleles were normal by DNA sequencing. Genetic heterogeneity was observed in this study, 10 mutations were of Asian or Asian/Indian origin, two were Kurdish, one Chinese, one Turkish, one Saudi, and the remainder were of Mediterranean origin. The presence of a large population of immigrants in the western province is responsible for the great heterogeneity at the molecular level, and for the difference observed in the frequencies of mutations from those reported in the eastern province of Saudi Arabia. Screening for β-thal mutations using PCR-ARMS for the seven most frequent mutations in the Saudi population followed by DNA sequencing of the unknown alleles could be useful for the implementation of a strategy for carrier detection and preimplantation genetic diagnosis in high risk families. 相似文献
516.
Flexural Strength of Internally Stiffened Tubular Steel Beam Filled with Recycled Concrete Materials
Ahmed W. Al Zand Mustafa M. Ali Riyadh Al-Ameri Wan Hamidon Wan Badaruzzaman Wadhah M. Tawfeeq Emad Hosseinpour Zaher Mundher Yaseen 《Materials》2021,14(21)
The flexural strength of Slender steel tube sections is known to achieve significant improvements upon being filled with concrete material; however, this section is more likely to fail due to buckling under compression stresses. This study investigates the flexural behavior of a Slender steel tube beam that was produced by connecting two pieces of C-sections and was filled with recycled-aggregate concrete materials (CFST beam). The C-section’s lips behaved as internal stiffeners for the CFST beam’s cross-section. A static flexural test was conducted on five large scale specimens, including one specimen that was tested without concrete material (hollow specimen). The ABAQUS software was also employed for the simulation and non-linear analysis of an additional 20 CFST models in order to further investigate the effects of varied parameters that were not tested experimentally. The numerical model was able to adequately verify the flexural behavior and failure mode of the corresponding tested specimen, with an overestimation of the flexural strength capacity of about 3.1%. Generally, the study confirmed the validity of using the tubular C-sections in the CFST beam concept, and their lips (internal stiffeners) led to significant improvements in the flexural strength, stiffness, and energy absorption index. Moreover, a new analytical method was developed to specifically predict the bending (flexural) strength capacity of the internally stiffened CFST beams with steel stiffeners, which was well-aligned with the results derived from the current investigation and with those obtained by others. 相似文献
517.
Mahmoud Mustafa Ali Abulmeaty Ali Madi Almajwal Heba Mohammed Zaher Hassan 《International journal of diabetes in developing countries.》2016,36(2):204-212
The frequent clinical use of bioelectrical impedance analysis (BIA) devices has made clinical evaluations of BIA-based parameters mandatory. This study was performed to define new cutoff points for the fat mass index, fat-free mass index, and percent body fat for overweight and obese men living in Riyadh, KSA. Three hundred sixty-two male subjects aged 18 to 62 years were enrolled in this cross-sectional study. The participants were divided into two groups; one group was assessed with an InBody 720 (n?=?179) device, and the other group was assessed with a Tanita BC-418 (n?=?183) device. Fat mass, fat mass index (FMI), fat-free mass, fat-free mass index (FFMI), and percent body fat (PBF) were measured. In addition, anthropometric measures, including weight, height, body mass index (BMI), waist circumference, hip circumference, waist hip ratio, and mid-arm circumference were included. Pearson correlation coefficients, Kappa analyses, and ROC curves were used. FMI exhibited the strongest positive correlation with BMI among all of the measured BIA-based parameters in both the InBody and Tanita groups (r?=?0.916 and 0.958, respectively, P?<?0.00001). ROC curves indicated that FMI was the most accurate parameter for the diagnosis of obesity in both groups (AUCs?=?0.970 and 0.980). The FMI, FFMI, and PBF cutoff values with the best sensitivities and specificities in both groups were 7.8 vs. 6.7 kg/m2, 19.2 vs. 20.7 kg/m2, and 27.8 vs. 24 %, respectively, based on the WHO criteria for the diagnosis of obesity in Asian population. FMI was the best predictor of obesity among all of the BIA-based parameters. Considerable differences were noted between the different machines. Knowledge of device-specific cutoff points would increase the clinical value of BIA in the diagnosis of obesity. 相似文献
518.
519.
Timothy P. LaBranche Michael I. Jesson Zaher A. Radi Chad E. Storer Julia A. Guzova Sheri L. Bonar Janice M. Thompson Fernando A. Happa Zachary S. Stewart Yutian Zhan Chris S. Bollinger Prashant N. Bansal Jeremy W. Wellen Dean P. Wilkie Steven A. Bailey Peter T. Symanowicz Martin Hegen Richard D. Head Nandini Kishore Gabriel Mbalaviele Debra M. Meyer 《Arthritis \u0026amp; Rheumatology》2012,64(11):3531-3542
520.
Dara S. Berger Zaher Merhi W. Allen Hogge Robert E. Ferrell 《Journal of assisted reproduction and genetics》2013,30(5):723-727