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排序方式: 共有1516条查询结果,搜索用时 17 毫秒
11.
12.
Mohammed AlSheef Mastourah Alotaibi Abdul Rehman Z. Zaidi Areej Alshamrani Aroub Alhamidi Syed Ziauddin A. Zaidi Noor Alanazi Sarah Alhathlool Ohoud Alarfaj Mohammed AlHazzaa Ghaydaa Kullab Amany Alboghdadly Amani Abu-Shaheen 《Saudi medical journal》2020,41(10):1063
Objectives:To identify the epidemiologic profile of cerebral vein thrombosis (CVT) among fasting women using oral contraceptive pills (OCPs) during the holy month of Ramadan.Methods:This retrospective study was conducted on all patients diagnosed with CVT and using OCPs from records at a tertiary care hospital in Riyadh, Saudi Arabia during 2016-2017. The study participants were categorized into 2 groups (an intermittently fasting group during the holy month of Ramadan and a non-fasting group).Results:Out of 108 female patients with CVT, 36.1% were secondary to OCP, of whom 41% participants were fasting. The most affected site was the transverse sinus. Holocephalic headache was more common amongst fasting group (68.8%) compared to non-fasting group (30.4%) (p=0.025). Dehydration (p=0.003) amongst the fasting group and protein S deficiency (p=0.027) in the non-fasting group were identified as the 2 prominent risk factors. Unfractionated heparin was the most common anticoagulant therapies used during the initiation phase for non-fasting (36.4%) and fasting groups (50%).Conclusion:All women who are using OCP should undergo formal written risk assessments for factors of CVT. Our study suggests that the negative effects of OCPs use might outweigh its benefits; thus, it should be prescribed with caution, more so in fasting patients. 相似文献
13.
Positron-emission tomography imaging of early events after transplantation of islets of Langerhans 总被引:2,自引:0,他引:2
Toso C Zaidi H Morel P Armanet M Andres A Pernin N Baertschiger R Slosman D Bühler LH Bosco D Berney T 《Transplantation》2005,79(3):353-355
The aim of our study was to assess cell trafficking and early events after intraportal islet transplantation. Sprague-Dawley rat islets were incubated for various times, with various concentrations of 2-[F]fluoro-2deoxy-D-glucose (FDG), and in presence of various glucose concentrations. FDG-labeled syngeneic islets or FDG alone were injected in rats. Radioactivity was measured in the liver and in various organs by positron-emission tomography for 6 hours. FDG uptake increased with incubation time or FDG concentration and decreased in presence of glucose. In vivo, all islets implanted in the liver, with an uptake 4.4 times higher than controls (44.2% vs. 10.1%, P=0.02). Radioactivity in the liver decreased at the same rate after injection of labeled-islets and FDG alone. Ex vivo labeling of islets and imaging of posttransplant early events were feasible. Islets engrafted exclusively in the liver. No islet loss could be demonstrated 6 hours after transplantation. 相似文献
14.
Kamrul Hasan Shivakumar Shankar Aadhar Sharma Alison Carter Razi Zaidi Suzie Cro John Skinner Andy Goldberg 《Journal of orthopaedics and traumatology》2016,17(4):291-295
Background
The burden of traumatic and elective hip surgery is set to grow. With an increasing number of techniques and implants against the background of an aging population, the emphasis on evidence-based treatment has never been greater. The purpose of this study was to assess changes in the levels of evidence in the hip literature over a decade.Materials and methods
Articles pertaining to hip surgery from the years 2000 and 2010 in Hip International, Journal of Arthroplasty, Journal of Bone and Joint Surgery and The Bone and Joint Journal were analysed. Articles were ranked by a five-point level of evidence scale and by type of study, according to guidelines from the Centre for Evidence-based Medicine.Results
531 articles were analysed from 48 countries. The kappa value for the inter-observer reliability showed excellent agreement between the reviewers for study type (κ = 0.956, P < 0.01) and for levels of evidence (κ = 0.772, P < 0.01). Between 2000 and 2010, the overall percentage of high-level evidence (levels I and II) studies more than doubled (12 to 31 %, P < 0.001). The most frequent study type was therapeutic; the USA and UK were the largest producers of published work in these journals, with contributions from other countries increasing markedly over the decade.Conclusions
There has been a significant increase in high levels of evidence in hip surgery over a decade (P < 0.001). We recommend that all orthopaedic journals consider implementing compulsory declaration by authors of the level of evidence to help enhance quality of evidence.Level of evidence
Level 2: economic and decision analysis.15.
M. Pazianas G. P. Butcher J. M. Subhani P. J. Finch L. Ang C. Collins R. P. Heaney M. Zaidi J. D. Maxwell 《Osteoporosis international》2005,16(1):56-63
Calcium malabsorption, hypocalcemia and skeletal demineralization are well-recognized features of untreated celiac disease. This study investigates calcium absorption and bone mineral density (BMD) after a prolonged, over 4 years, treatment with a gluten-free diet. Twenty-four adult females with treated celiac disease and twenty age- and sex-matched control subjects were studied. Mean body mass index (MBI), energy intake, serum calcium, and serum 25(OH)D concentrations in treated celiacs did not differ from controls. However, while both dietary calcium and protein intake were significantly higher in celiacs (P<0.012), fractional calcium absorption was lower (mean percentage±SD; treated 39.8±12 versus controls 52.3±10, P<0.001). Thus, after adjusting for calcium intake, the estimated amount of calcium absorbed daily was similar in both groups. Whole body, spine and trochanter BMD were significantly lower in treated celiac patients compared with controls (P<0.05). There were significant inverse correlations between: serum parathyroid hormone (PTH) and femoral neck or total body BMD (P<0.01), PTH and duration of gluten-free diet (P=0.05), and fractional calcium absorption and alkaline phosphatase (P=0.022). Increased calcium intake could potentially compensate for the reduced fractional calcium absorption in treated adult celiac patients, but may not normalize the BMD. In addition, the inverse correlation between PTH and time following treatment is suggestive of a continuing long-term benefit of gluten withdrawal on bone metabolism in celiac patients. 相似文献
16.
Mone Zaidi Terry F. Davies Alberta Zallone Harry C. Blair Jameel Iqbal Surinder S. Moonga Jeffrey Mechanick Li Sun 《Current osteoporosis reports》2009,7(2):47-52
It has become accepted by virtue of rich anecdotal experience and clinical research that thyrotoxicosis is associated with
high-turnover osteoporosis. The bone loss, primarily due to accelerated resorption that is not compensated by a coupled increase
in bone formation, has been attributed solely to elevated thyroid hormone levels. Evidence using mice lacking the thyroid
hormone receptors α and β establishes a role for thyroid hormones in regulating bone remodeling but does not exclude an independent
action of thyroid-stimulating hormone (TSH), levels of which are low in hyperthyroid states, even when thyroid hormones are
normal, as after thyroxine supplementation and in subclinical hyperthyroidism. We show that TSH directly suppresses bone remodeling
and that TSH receptor null mice have profound bone loss, suggesting that reduced TSH signaling contributes to hyperthyroid
osteoporosis. TSH and its receptor could become valuable drug targets in treating bone loss. 相似文献
17.
Carolyn L. Wang Jennifer G. Schopp Kimia Kani Jonelle M. Petscavage-Thomas Sadaf Zaidi Dan S. Hippe Angelisa M. Paladin William H. Bush 《European journal of radiology》2013
Purpose
We developed a computer-based interactive simulation program for teaching contrast reaction management to radiology trainees and compared its effectiveness to high-fidelity hands-on simulation training.Materials and methods
IRB approved HIPAA compliant prospective study of 44 radiology residents, fellows and faculty who were randomized into either the high-fidelity hands-on simulation group or computer-based simulation group. All participants took separate written tests prior to and immediately after their intervention. Four months later participants took a delayed written test and a hands-on high-fidelity severe contrast reaction scenario performance test graded on predefined critical actions.Results
There was no statistically significant difference between the computer and hands-on groups’ written pretest, immediate post-test, or delayed post-test scores (p > 0.6 for all). Both groups’ scores improved immediately following the intervention (p < 0.001). The delayed test scores 4 months later were still significantly higher than the pre-test scores (p ≤ 0.02). The computer group's performance was similar to the hands-on group on the severe contrast reaction simulation scenario test (p = 0.7). There were also no significant differences between the computer and hands-on groups in performance on the individual core competencies of contrast reaction management during the contrast reaction scenario.Conclusion
It is feasible to develop a computer-based interactive simulation program to teach contrast reaction management. Trainees that underwent computer-based simulation training scored similarly on written tests and on a hands-on high-fidelity severe contrast reaction scenario performance test as those trained with hands-on high-fidelity simulation. 相似文献18.
Vees H Buchegger F Albrecht S Khan H Husarik D Zaidi H Soloviev D Hany TF Miralbell R 《BJU international》2007,99(6):1415-1420
OBJECTIVES: To assess the value of positron emission tomography (PET)/computed tomography (CT) with either (18)F-choline and/or (11)C-acetate, of residual or recurrent tumour after radical prostatectomy (RP) in patients with a prostate-specific antigen (PSA) level of <1 ng/mL and referred for adjuvant or salvage radiotherapy. PATIENTS AND METHODS: In all, 22 PET/CT studies were performed, 11 with (18)F-choline (group A) and 11 with (11)C-acetate (group B), in 20 consecutive patients (two undergoing PET/CT scans with both tracers). The median (range) PSA level before PET/CT was 0.33 (0.08-0.76) ng/mL. Endorectal-coil magnetic resonance imaging (MRI) was used in 18 patients. Nineteen patients were eligible for evaluation of biochemical response after salvage radiotherapy. RESULTS: There was abnormal local tracer uptake in five and six patients in group A and B, respectively. Except for a single positive obturator lymph node, there was no other site of metastasis. In the two patients evaluated with both tracers there was no pathological uptake. Endorectal MRI was locally positive in 15 of 18 patients; 12 of 19 responded with a marked decrease in PSA level (half or more from baseline) 6 months after salvage radiotherapy. CONCLUSIONS: Although (18)F-choline and (11)C-acetate PET/CT studies succeeded in detecting local residual or recurrent disease in about half the patients with PSA levels of <1 ng/mL after RP, these studies cannot yet be recommended as a standard diagnostic tool for early relapse or suspicion of subclinical minimally persistent disease after surgery. Endorectal MRI might be more helpful, especially in patients with a low likelihood of distant metastases. Nevertheless, further research with (18)F-choline and/or (11)C-acetate PET with optimal spatial resolution might be needed for patients with a high risk of distant relapse after RP even at low PSA values. 相似文献
19.
Ursodeoxycholic Acid Enhances Fractional Calcium Absorption in Primary Biliary Cirrhosis 总被引:2,自引:0,他引:2
A. Verma J. D. Maxwell L. Ang T. Davis S. Hodges T. C. Northfield M. Zaidi M. Pazianas 《Osteoporosis international》2002,13(8):677-682
Bone disease is a frequently reported complication in primary biliary cirrhosis (PBC), but its pathogenesis is poorly understood.
Calcium malabsorption has been considered as an important contributing factor. Ursodeoxycholic acid (UDCA) is the treatment
of choice in PBC, improving survival, but its effect on calcium absorption is unknown. In this study, we have measured fractional
calcium absorption, using a single isotope method, in a group of female PBC patients (median age: 60 years, range: 46–78 years)
and age-matched female controls (median age: 58 years, range: 36–74). Bone mineral density (BMD) in PBC patients was significantly
lower than age-matched controls (g/cm2± SEM; lumbar spine: controls 1.139 ± 0.028, PBC patients 1.004 ± 0.026, p= 0.0028; femoral neck: controls 0.944 ± 0.034, PBC patients 0.819 ± 0.023, p = 0.0032). Twenty two PBC patients, who were not vitamin D-deficient, were off and on UDCA for ~1 month and ~8 weeks, respectively.
Fractional calcium absorption in PBC patients prior to UDCA treatment (mean ± SEM, 33.8 ± 2.6%) was significantly lower than
controls (52.0 ± 2.4%, p<0.001). Following UDCA therapy, fractional calcium absorption increased significantly (Off UDCA: 33.1 ± 2.6%, On UDCA: 36.6
± 2.5%, p<0.0058). Osteocalcin levels were significantly raised in the PBC group (mean ± SEM, ng/ml, 41.4 ± 2.02) compared to controls
(31.1 ± 2.64, p= 0.002). There were no differences in parathyroid hormone (PTH) or 25-hydroxyvitamin D levels between these two groups or
following UDCA therapy. In conclusion, we found that PBC patients display low spinal and femoral neck BMD, reduced fractional
calcium absorption, and elevated plasma osteocalcin. The calcium malabsorption is corrected partially by UDCA therapy. Long-term
studies are required to determine whether this effect can be sustained, and whether a sustained increase in fractional calcium
absorption can translate into a favorable change in bone strength in patients with PBC.
Received: 27 November 2001 / Accepted: 11 April 2002 相似文献
20.
E. Leighton Durham Hee Jung Jeong Tyler M. Moore Randolph M. Dupont Carlos Cardenas-Iniguez Zaixu Cui Farrah E. Stone Marc G. Berman Benjamin B. Lahey Antonia N. Kaczkurkin 《Neuropsychopharmacology》2021,46(7):1333
Childhood is an important time for the manifestation of psychopathology. Psychopathology is characterized by considerable comorbidity which is mirrored in the underlying neural correlates of psychopathology. Both common and dissociable variations in brain volume have been found across multiple mental disorders in adult and youth samples. However, the majority of these studies used samples with broad age ranges which may obscure developmental differences. The current study examines associations between regional gray matter volumes (GMV) and psychopathology in a large sample of children with a narrowly defined age range. We used data from 9607 children 9–10 years of age collected as part of the Adolescent Brain Cognitive DevelopmentSM Study (ABCD Study®). A bifactor model identified a general psychopathology factor that reflects common variance across disorders and specific factors representing internalizing symptoms, ADHD symptoms, and conduct problems. Brain volume was acquired using 3T MRI. After correction for multiple testing, structural equation modeling revealed nearly global inverse associations between regional GMVs and general psychopathology and conduct problems, with associations also found for ADHD symptoms (pfdr-values ≤ 0.048). Age, sex, and race were included as covariates. Sensitivity analyses including total GMV or intracranial volume (ICV) as covariates support this global association, as a large majority of region-specific results became nonsignificant. Sensitivity analyses including income, parental education, and medication use as additional covariates demonstrate largely convergent results. These findings suggest that globally smaller GMVs are a nonspecific risk factor for general psychopathology, and possibly for conduct problems and ADHD as well.Subject terms: Human behaviour, Risk factors, Neuroscience 相似文献