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排序方式: 共有891条查询结果,搜索用时 15 毫秒
31.
Matthew J. Budoff Sandy Liu David Chow Ferdinand Flores Brian Hsieh Dan Gebow Tony DeFrance Naser Ahmadi 《Atherosclerosis》2014
Background: Previous studies have shown that computed tomography coronary angiography (CTA) in patients with suspected coronary artery disease (CAD) predicts short term adverse events. However, there is no current data on whether identifying atherosclerosis on CTA impacts outcomes. We performed a case–control study to assess whether information from CTA can improve outcomes. Methods: 4244 symptomatic patients (mean age 58 ± 9, 62.5% male) without known CAD who underwent CTA (n = 2538) to rule out CAD were matched to 1706 patients who underwent standard of care in an academic cardiology clinic. Patients were propensity-matched by gender, age, ethnicity, CAD risk factors and follow-up duration. The primary outcome measure was all-cause mortality. Multivariable Cox proportional hazards models incorporated age, gender and traditional risk factors for coronary disease as well as pre-test probability of CAD. Results: There were no significant differences in age, gender, conventional risk factors between groups (p > 0.05). During a mean follow up of 80 ± 11 months, the overall death rate was 6.3% (270 deaths). Death rate was significantly lower in CTA group (n = 106, 4.2%) as compared to the control group (n = 184, 10.8%, p = 0.001). Event free survival was 95.8% and 89.2% in CTA and standard of care groups, respectively. Risk-adjusted hazard ratio of death were 2.5 (95%CI: 1.6–6.7, p = 0.003) in standard of care cohort as compared to CTA group. Multivariate analysis demonstrated that undergoing coronary CTA resulted in a risk reduction of 32%, p = 0·0001. Conclusions: Improved knowledge of atherosclerosis or increased anti-atherosclerotic therapies among those undergoing CTA may have contributed to improved survival. Our results provide evidence of potential benefit from scanning for atherosclerosis with CTA in symptomatic patients. Large randomized trials are warranted. 相似文献
32.
Miklos Z. Molnar Mohamed S. Naser Connie M. Rhee Kamyar Kalantar-Zadeh Suphamai Bunnapradist 《Transplantation reviews (Orlando, Fla.)》2014,28(2):56-62
Mineral and bone diseases (MBD) are common in patients with chronic kidney disease who undergo kidney transplantation. The incidence, types and severity of MBD vary according to the duration of chronic kidney disease, presence of comorbid conditions and intake of certain medications. Moreover, multiple types of pathology may be responsible for MBD. After successful reversal of uremia by kidney transplantation, many bone and mineral disorders improve, while immunosuppression, other medications, and new and existing comorbidities may result in new or worsening MBD. Chronic kidney disease is also common after kidney transplantation and may impact bone and mineral disease. In this article, we reviewed the prevalence, pathophysiology, and impact of MBD on post-transplant outcomes. We also discussed the diagnostic approach; immunosuppression management and potential treatment of MBD in kidney transplant recipients. 相似文献
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34.
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
35.
36.
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
37.
Rezk NL White N Bridges AS Abdel-Megeed MF Mohamed TM Moselhy SS Kashuba AD 《Therapeutic drug monitoring》2008,30(5):611-619
Studying the pharmacokinetics of antiretroviral drugs in breast milk has important implications for the health of both the mother and the infant, particularly in resource-poor countries. Breast milk is a highly complex biological matrix, yet it is necessary to develop and validate methods in this matrix, which simultaneously measure multiple analytes, as women may be taking any number of drug combinations to combat human immunodeficiency virus infection. Here, we report a novel extraction method coupled to high-performance liquid chromatography and tandem mass spectrometry for the accurate, precise, and specific measurement of 7 antiretroviral drugs currently prescribed to infected mothers. Using 200 microL of human breast milk, simultaneous quantification of lamivudine (3TC), stavudine (d4T), zidovudine (ZDV), nevirapine (NVP), nelfinavir (NFV), ritonavir, and lopinavir was validated over the range of 10-10,000 ng/mL. Intraday accuracy and precision for all analytes were 99.3% and 5.0 %, respectively. Interday accuracy and precision were 99.4 % and 7.8%, respectively. Cross-assay validation with UV detection was performed using clinical breast milk samples, and the results of the 2 assays were in good agreement (P = 0.0001, r = 0.97). Breast milk to plasma concentration ratios for the different antiretroviral drugs were determined as follows: 3TC = 2.96, d4T = 1.73, ZDV = 1.17, NVP = 0.82, and NFV = 0.21. 相似文献
38.
Faris H. Lami Rana K. Al Naser 《Burns : journal of the International Society for Burn Injuries》2019,45(2):479-483
This study was conducted to determine the epidemiological and clinical characteristics of burn injuries, estimate the case fatality rate for burn patients, and determine the main determinants of the associated death among burn patients who were admitted to Baghdad Burn Hospital, Medical City Teaching Hospitals, Baghdad, Iraq during 2015. This study involved a retrospective review of medical records of all burn patients who were admitted to Baghdad Burn Hospital in 2015. Data were collected using a special form and included information on demographic characteristics and burn characteristics and outcomes. A total of 676 patients with burn were included in this study, who constituted 75% of admitted patients. The remaining was admitted for treatment of old scars. About one third of patients (37.0%) aged 21–30 years, 67.1% were males, 34.8% were military personnel, and 60.7% of the patients had primary school education. About 71.6% of patients were burned by flame and 23.4% were burned by hot fluid. Half of patients had a second degree burns. Almost half of patients had 11–20% of their body surface area affected. About 13% of patients died, mainly due to multiple organs failure (53.3%), septicemia (44.4%), and shock (2.2%). In conclusion, young adults and children, males, and low educated patients represent the majority of admitted burn cases in Iraq. Flame and scalds were the most important causes of burn. More than one tenth of patients died mostly due to septicemia and multi-organ failure. 相似文献
39.
40.
Dib C Araoz PA Davies NP Dearani JA Ammash NM 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2012,39(2):249-254
Reversible causes of miscarriage are many, but they affect only 1% of women who are trying to conceive. Herein, we describe the case of a 23-year-old woman who presented for evaluation of repeated miscarriages and was found to have hypoxemia and erythrocytosis. Further evaluation revealed hypoplastic right-heart syndrome with an intracardiac shunt. She underwent hybrid repair with pulmonary valve balloon valvuloplasty, followed by surgery to perform atrial septal defect closure and a Glenn anastomosis. The erythrocytosis and hypoxemia resolved, and she was able to conceive and deliver a healthy baby at term 2 years later. This is a unique case of a rare congenital heart defect that went unnoticed until adulthood, when attempts at pregnancy failed because of the associated hypoxemia. Timely and appropriate treatment led to a successful pregnancy after repeated miscarriages. This case exemplifies the need for a comprehensive medical evaluation of every woman with a history of multiple miscarriages to determine whether a reversible cause exists. 相似文献