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41.
42.
Moudhi Alroomi Rajesh Rajan Ahmad Alsaber Jiazhu Pan Mohammed Abdullah Hassan Abdelnaby Wael Aboelhassan Noor AlNasrallah Bader AlBader Haya Malhas Maryam Ramadhan Soumoud Hussein Naser Alotaibi Mohammad Al Saleh Kobalava D. Zhanna Farah Almutairi 《Journal of clinical laboratory analysis》2022,36(4)
BackgroundThis study investigates in‐hospital mortality amongst patients with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and its relation to serum levels of gamma‐glutamyl transferase (GGT).MethodsPatients were stratified according to serum levels of gamma‐glutamyl transferase (GGT) (GGT<50 IU/L or GGT≥50 IU/L).ResultsA total of 802 participants were considered, amongst whom 486 had GGT<50 IU/L and a mean age of 48.1 (16.5) years, whilst 316 had GGT≥50 IU/L and a mean age of 53.8 (14.7) years. The chief sources of SARS‐CoV‐2 transmission were contact (366, 45.7%) and community (320, 40%). Most patients with GGT≥50 IU/L had either pneumonia (247, 78.2%) or acute respiratory distress syndrome (ARDS) (85, 26.9%), whilst those with GGT<50 IU/L had hypertension (141, 29%) or diabetes mellitus (DM) (147, 30.2%). Mortality was higher amongst patients with GGT≥50 IU/L (54, 17.1%) than amongst those with GGT<50 IU/L (29, 5.9%). More patients with GGT≥50 required high (83, 27.6%) or low (104, 34.6%) levels of oxygen, whereas most of those with GGT<50 had no requirement of oxygen (306, 71.2%). Multivariable logistic regression analysis indicated that GGT≥50 IU/L (odds ratio [OR]: 2.02, 95% confidence interval [CI]: 1.20–3.45, p=0.009), age (OR: 1.05, 95% CI: 1.03–1.07, p<0.001), hypertension (OR: 2.06, 95% CI: 1.19–3.63, p=0.011), methylprednisolone (OR: 2.96, 95% CI: 1.74–5.01, p<0.001) and fever (OR: 2.03, 95% CI: 1.15–3.68, p=0.016) were significant predictors of all‐cause cumulative mortality. A Cox proportional hazards regression model (B = −0.68, SE =0.24, HR =0.51, p = 0.004) showed that patients with GGT<50 IU/L had a 0.51‐times lower risk of all‐cause cumulative mortality than patients with GGT≥50 IU/L.ConclusionHigher levels of serum GGT were found to be an independent predictor of in‐hospital mortality. 相似文献
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44.
Zaki I. Zaki Saad H. Alotaibi Bashayer A. Alhejji Naser Y. Mostafa Mohammed A. Amin Mohsen M. Qhatani 《Materials》2022,15(5)
In this study, a high-density ZrN/ZrSi2 composite reinforced with ZrO2 as an inert phase was synthesized under vacuum starting with a Zr-Si4N3-ZrO2 blend using combustion-synthesis methodology accompanied by compaction. The effects of ZrO2 additions (10–30 wt%) and compression loads (117–327 MPa) on the microstructure, porosity and hardness of the samples were studied. The process was monitored using XRD, SEM, EDS, porosity, density and hardness measurements. Thermodynamic calculations of the effect of ZrO2 addition on the combustion reaction were performed including the calculation of the adiabatic temperatures and the estimation of the fractions of the liquid phase. The addition of up to 20 wt% ZrO2 improved the hardness and reduced the porosity of the samples. Using 20 wt% ZrO2, the sample porosity was reduced to 1.66 vol%, and the sample hardness was improved to 1165 ± 40.5 HV at 234 MPa. 相似文献
45.
Wael Soliman Martin Vinten Birgit Sander Kamell Abd El‐Naser Soliman Sameer Yehya Mohamed Saad Abdel Rahman Michael Larsen 《Acta ophthalmologica. Supplement》2008,86(4):365-371
Purpose: To assess the effect of intravitreal bevacizumab on diabetic macular oedema (DMO) and retinal vessel calibres. Methods: We performed a consecutive case series study in which 10 consecutive eyes with diffuse DMO, two of which had not previously been treated, received an intravitreal injection of bevacizumab 1 mg, which was followed by two more injections at 6‐week intervals. Fundus photography and optical coherence tomography (OCT) were carried out at baseline immediately before injection and at 1, 2.5 and 4 months after the first injection. Outcome measures were best corrected visual acuity (BCVA) in Early Treatment Diabetic Retinopathy Study letters, macular volume, foveal subfield thickness and vessel diameter measurement. Results: Intravitreal administration of bevacizumab was followed by a mean increase in BCVA of 7.3 ± 17 (mean ± standard deviation) letters between baseline and month 4, which was 1 month after the last injection (p < 0.0001). This was accompanied by a reduction in mean macular volume from 9.90 ± 1.9 mm3 to 8.96 ± 2.4 mm3 (p = 0.002) and in foveal subfield thickness from 447 ± 117 μm to 388 ± 117 μm (p = 0.03). Two eyes with early proliferative diabetic retinopathy lost all signs of proliferation without any evidence of fibrosis. Although there was a trend towards vasoconstriction, the changes in vessel diameters (arteries and veins) after 4 months of intravitreal Avastin injection were not statistically significant (p = 0.9 and p = 0.17, respectively). Foveal thickness in non‐injected fellow eyes with DMO changed from 428 ± 153 μm at baseline to 383 ± 151 μm at 4 months (p = 0.1), which did not reach statistical significance. Conclusions: Intravitreal bevacizumab 1 mg every 6 weeks was followed by a moderate reduction in DMO without normalization of foveal and macular thickness. Our observations suggest that a larger study where patients are examined sooner after injection is needed to elucidate the potential relationship between changes in retinal vessel diameters and thickness changes in DMO. 相似文献
46.
Shafran I Piromalli C Decker JW Sandoval J Naser SA El-Zaatari FA 《Digestive diseases and sciences》2002,47(9):2079-2081
Crohn's disease (CD) is an idiopathic chronic inflammatory bowel disease (IBD). Accurate diagnosis of the disease is of great clinical importance to assess its prognosis and success of therapy. Recent studies have validated and confirmed the potential utility of anti-Saccharomyces cerevisiae (baker's yeast; ASCA) IgG/IgA antibodies and anti-M. avium ss. paratuberculosis p35/p36 antibodies, separately, as serological markers to identify patients with CD. The efficacy of these markers was evaluated in the same patients with Crohn's disease. The anti-ASCA IgA/IgG and the anti-M. avium ss. paratuberculosis p35/p36 antibodies were positive in 60% (36/60) and 86.7% (52/60) of CD patients, respectively. When all the serologic markers were considered, the sensitivity in detecting CD was increased to 95.0% (57/60); 21 of 24 ASCA-negative patients were p35/p36-positive and five of eight of p35/p36-negative patients were ASCA-positive. This investigation further establishes the utility of p35 and p36 recombinant clones for the diagnosis of CD, and reveals the complimentary role of ASCA and p35 and p36 for effective detection of CD. Larger studies are needed to investigate the combined use of these serologic markers for the diagnosis of CD. 相似文献
47.
M. Maiwald R. Oehme O. March T. N. Petney P. Kimmig K. Naser H. A. Zappe D. Hassler M. von Knebel Doeberitz 《Epidemiology and infection》1998,121(1):103-108
The risk of Borrelia burgdorferi infection and the value of antibiotic prophylaxis after tick bite are controversial. In this study, performed in two areas of southwestern Germany, ticks were collected from 730 patients and examined by the polymerase chain reaction (PCR) for B. burgdorferi. To assess whether transmission of B. burgdorferi occurred, the patients were clinically and serologically examined after tick removal and during follow-up examinations. Data from all tick bites gave a total transmission rate of 2.6% (19 patients). Eighty-four ticks (11.3%) were PCR positive. Transmission occurred to 16 (26.7%) of 60 patients who were initially seronegative and could be followed up after the bite of an infected tick. These results indicate that the transmission rate from infected ticks in Europe is higher than previously assumed. Examination of ticks and antibiotic prophylaxis in the case of positivity appears to be indicated. 相似文献
48.
Bioequivalence studies, required by law whenever a new formulation of an existing drug product is introduced to the market, are designed to test whether the bioavailability, defined as the rate and extent to which a substance reaches systemic circulation, is equivalent for each of two or more formulations. Detection and treatment of outlying data in bioequivalence studies are practically important, because inclusion or deletion of potential outlying data may lead to a different conclusion concerning bioequivalence. A review of the literature reveals that four different methods have been proposed for detecting outliers in bioavailability/bioequivalence studies. We present the results of an extensive computer simulation testing the small sample performance of these four testing methods, the results of which indicate that one of these, the estimates distance test, is substantially more powerful than the alternatives. 相似文献
49.
GOAL: To assess the sensitivity/specificity of the serologic markers: perinuclear antineutrophil cytoplasmic antibody (pANCA) and anti-saccharomyces cerevisiae antibody (ASCA) in children diagnosed with inflammatory bowel disease (IBD), living in West Virginia. BACKGROUND: In recent years, serologic markers have been used to differentiate between CD and UC diseases in children. The clinical usefulness of these markers in children was restricted by their low sensitivity and specificity. Racial and ethnic diversity may alter the accuracy of these markers in children. The demographic homogeneity of the West Virginia population may offer a better clinical setup to reassess the utility of those markers in children with IBD. STUDY: A retrospective analysis of all the charts of children diagnosed with IBD was performed at the gastroenterology clinics of Marshall University, Huntington, WV; and West Virginia University, Charleston Division, Charleston, WV. The diagnosis of IBD was established according to clinical, radiologic, and endoscopic data. Laboratory data and serum markers were recorded, and their accuracy to diagnose UC or CD was assessed. RESULTS: A total of 101 charts were reviewed, of which only 90 (89%) included serologic markers and were considered for further analysis. Disease distribution included: UC-41, CD-44, and indeterminate colitis (IC)-7 (2 patients changed diagnosis after colectomy). Serum antibody pANCA had a sensitivity of 73% and specificity of 84% for UC, but only 16% and 35% for CD, respectively. Serum antibody ASCA had a sensitivity of 58% and specificity of 92% for CD, but only 7% and 49% for UC, respectively. The outer membrane porin to Escherichia coli antibody (anti-OmpC) was available in 54 (59%) children and demonstrated a very poor sensitivity for both diseases (sensitivity<11%). CONCLUSION: Despite our homogeneous patient population, pANCA and ASCA antibodies had an inadequate sensitivity/specificity for children with UC or CD. Those antibodies were not useful for our small number of patients with IC. 相似文献
50.