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排序方式: 共有1421条查询结果,搜索用时 15 毫秒
1.
Maadrika M.N.P. Kanglie Nanko de Graaf Femke Beije Elise M.J. Brouwers Sabine D.M. Theuns-Valks Frits H. Jansen Diederick B.W. de Roy van Zuidewijn Bas Verhoeven Rick R. van Rijn Roel Bakx 《Journal of pediatric surgery》2019,54(3):500-506
Background
There is a lack of studies addressing the occurrence of negative intraoperative findings (that is the absence of intussusception) after an unsuccessful hydrostatic reduction of an ileocolic intussusception. The aim of this study is to determine the incidence of negative intraoperative findings after unsuccessful hydrostatic reduction of ileocolic intussusception.Methods
We conducted a multicentre retrospective study of all children aged 0–18?years treated for ileocolic intussusception from January 1, 2010 to December 31, 2015 in 9 Dutch hospitals. Primary outcome measure was the percentage of children without an intussusception during surgical exploration after unsuccessful hydrostatic reduction.Results
In the study period 436 patients were diagnosed with an ileocolic intussusception. Of these, 408 patients underwent hydrostatic reduction of an ileocolic intussusception. 112 patients (27.5%) underwent surgery after an unsuccessful hydrostatic reduction. In 13 (11.6%) patients no intraoperative evidence of intussusception was found. Patients who underwent surgical intervention after unsuccessful hydrostatic reduction were significantly younger than patients who had a successful hydrostatic reduction; there was no gender difference.Conclusion
A substantial number of children (11.6%) underwent a laparotomy after unsuccessful hydrostatic reduction in whom no intussusception was found intraoperatively. We suggest initiating laparoscopy instead of laparotomy when surgery is necessary.Level of evidence
Level II. 相似文献2.
Nittaya Phanuphak Nipat Teeratakulpisarn Frits van Griensven Nitiya Chomchey Suteeraporn Pinyakorn James LK Fletcher Rapee Trichavaroj Supanit Pattanachaiwit Nelson Michael Praphan Phanuphak Jerome H Kim Jintanat Ananworanich 《Journal of the International AIDS Society》2015,18(1)
Introduction
HIV transmission risk is highest during acute HIV infection (AHI). We evaluated HIV RNA in the anogenital compartment in men who have sex with men (MSM) during AHI and compared time to undetectable HIV RNA after three-drug versus five-drug antiretroviral therapy (ART) to understand risk for onward HIV transmission.Methods
MSM with AHI (n=54) had blood, seminal plasma and anal lavage collected for HIV RNA at baseline, days 3 and 7, and weeks 2, 4, 12 and 24. Data were compared between AHI stages: 1 (fourth-generation antigen-antibody combo immunoassay [IA]–, third-generation IA–, n=15), 2 (fourth-generation IA+, third-generation IA–, n=9) and 3 (fourth-generation IA+, third-generation IA+, western blot–/indeterminate, n=30) by randomization to five-drug (tenofovir+emtricitabine+efavirenz+raltegravir+maraviroc, n=18) versus three-drug (tenofovir+emtricitabine+efavirenz, n=18) regimens.Results
Mean age was 29 years and mean duration since HIV exposure was 15.4 days. Mean baseline HIV RNA was 5.5 in blood, 3.9 in seminal plasma and 2.6 log10 copies/ml in anal lavage (p<0.001). Blood and seminal plasma HIV RNA were higher in AHI Stage 3 compared to Stage 1 (p<0.01). Median time from ART initiation to HIV RNA <50 copies/ml was 60 days in blood, 15 days in seminal plasma and three days in anal lavage. Compared with the three-drug ART, the five-drug ART had a shorter time to HIV RNA <1500 copies/ml in blood (15 vs. 29 days, p=0.005) and <50 copies/ml in seminal plasma (13 vs. 24 days, p=0.048).Conclusions
Among MSM with AHI, HIV RNA was highest in blood, followed by seminal plasma and anal lavage. ART rapidly reduced HIV RNA in all compartments, with regimen intensified by raltegravir and maraviroc showing faster HIV RNA reductions in blood and seminal plasma. 相似文献3.
Van Mieghem CA Bruining N Schaar JA McFadden E Mollet N Cademartiri F Mastik F Ligthart JM Granillo GA Valgimigli M Sianos G van der Giessen WJ Backx B Morel MA Van Es GA Sawyer JD Kaplow J Zalewski A van der Steen AF de Feyter P Serruys PW 《The international journal of cardiovascular imaging》2005,21(4):425-441
Death or myocardial infarction, the most serious clinical consequences of atherosclerosis, often result from plaque rupture at non-flow limiting lesions. Current diagnostic imaging with coronary angiography only detects large plaques that already impinge on the lumen and cannot accurately identify those that have a propensity to cause unheralded events. Accurate evaluation of the composition or of the biomechanical characteristics of plaques with invasive or non-invasive methods, alone or in conjunction with assessment of circulating biomarkers, could help identify high-risk patients, thus providing the rationale for aggressive treatments in order to reduce future clinical events. The IBIS (Integrated Biomarker and Imaging Study) study is a prospective, single-center, non-randomized, observational study conducted in Rotterdam. The aim of the IBIS study is to evaluate both invasive (quantitative coronary angiography, intravascular ultrasound (IVUS) and palpography) and non-invasive (multislice spiral computed tomography) imaging techniques to characterize non-flow limiting coronary lesions. In addition, multiple classical and novel biomarkers will be measured and their levels correlated with the results of the different imaging techniques. A minimum of 85 patients up to a maximum of 120 patients will be included. This paper describes the study protocol and methodological solutions that have been devised for the purpose of comparisons among several imaging modalities. It outlines the analyses that will be performed to compare invasive and non-invasive imaging techniques in conjunction with multiple biomarkers to characterize non-flow limiting subclinical coronary lesions. 相似文献
4.
The addition of pyridoxal-5-phosphate for assay of alanine aminotransferase has been recommended. The referral methods are inconvenient for high volume instrumentation due to use of multiple reagents and blanks. We adapted a well-documented method to the centrifugal analyzer as a reference for adaptation of two kit methods. Reference intervals obtained and linearity determined were all similar. The kit methods compared favorably to the referral method. Linear regression analysis yielded the following: DOW = 1.011 BERG + 1.666, r = 0.9965; SKI = 0.938 BERG + 4.559, r = 0.9926; and DSKI = 1.028 BERG + 1.051, r = 0.9889. Precision of the assays was acceptable. We concluded that automation of reagent kits incorporating pyridoxal-5-phosphate is feasible and the assays compared favorably to a recommended method. High volume instrumentation can be used without denigration of analytical quality and to allow comparability to a documented method for interlaboratory review. 相似文献
5.
6.
Frits H.A. van Heijster Sandra Heskamp Vincent Breukels Andor Veltien Gerben M. Franssen Kees .F.J. Jansen Otto C. Boerman Jack A. Schalken Tom W.J. Scheenen Arend Heerschap 《NMR in biomedicine》2020,33(10)
Reprogramming of energy metabolism in the development of prostate cancer can be exploited for a better diagnosis and treatment of the disease. The goal of this study was to determine whether differences in glucose and pyruvate metabolism of human prostate cancer cells with dissimilar aggressivenesses can be detected using hyperpolarized [1‐13C]pyruvate MRS and [18F]FDG‐PET imaging, and to evaluate whether these measures correlate. For this purpose, we compared murine xenografts of human prostate cancer LNCaP cells with those of more aggressive PC3 cells. [1‐13C]pyruvate was hyperpolarized by dissolution dynamic nuclear polarization (dDNP) and [1‐13C]pyruvate to lactate conversion was followed by 13C MRS. Subsequently [18F]FDG uptake was investigated by static and dynamic PET measurements. Standard uptake values (SUVs) for [18F]FDG were significantly higher for xenografts of PC3 compared with those of LNCaP. However, we did not observe a difference in the average apparent rate constant kpl of 13C label exchange from pyruvate to lactate between the tumor variants. A significant negative correlation was found between SUVs from [18F]FDG PET measurements and kpl values for the xenografts of both tumor types. The kpl rate constant may be influenced by various factors, and studies with a range of prostate cancer cells in suspension suggest that LDH inhibition by pyruvate may be one of these. Our results indicate that glucose and pyruvate metabolism in the prostate cancer cell models differs from that in other tumor models and that [18F]FDG‐PET can serve as a valuable complementary tool in dDNP studies of aggressive prostate cancer with [1‐13C]pyruvate. 相似文献
7.
Lorne A. Clarke Roberto Giugliani Nathalie Guffon Simon A. Jones Hillary A. Keenan Maria V. Munoz-Rojas Torayuki Okuyama David Viskochil Chester B. Whitley Frits A. Wijburg Joseph Muenzer 《Clinical genetics》2019,96(4):281-289
Mucopolysaccharidosis type I (MPS I) is a rare autosomal recessive disorder resulting from pathogenic variants in the α-L-iduronidase (IDUA) gene. Clinical phenotypes range from severe (Hurler syndrome) to attenuated (Hurler-Scheie and Scheie syndromes) and vary in age of onset, severity, and rate of progression. Defining the phenotype at diagnosis is essential for disease management. To date, no systematic analysis of genotype-phenotype correlation in large MPS I cohorts have been performed. Understanding genotype-phenotype is critical now that newborn screening for MPS I is being implemented. Data from 538 patients from the MPS I Registry (380 severe, 158 attenuated) who had 2 IDUA alleles identified were examined. In the 1076 alleles identified, 148 pathogenic variants were reported; of those, 75 were unique. Of the 538 genotypes, 147 (27%) were unique; 40% of patients with attenuated and 22% of patients with severe MPS I had unique genotypes. About 67.6% of severe patients had genotypes where both variants identified are predicted to severely disrupt protein/gene function and 96.1% of attenuated patients had at least one missense or intronic variant. This dataset illustrates a close genotype/phenotype correlation in MPS I but the presence of unique IDUA missense variants remains a challenge for disease prediction. 相似文献
8.
9.
10.
Holleman F Endert E Prummel MF van Vessem-Timmermans M Wiersinga WM Fliers E 《The Netherlands journal of medicine》2005,63(9):348-353
BACKGROUND: While reference values for 24-hour free urinary cortisol excretion and the overnight 1 mg dexa-methasone-suppression test in the healthy population are available, cut-off values in patients clinically suspected of Cushing's syndrome have to be established. METHODS: This was a prospective follow-up study in one academic centre of 144 patients with clinical suspicion of Cushing's syndrome (group A) and 50 patients with adrenal incidentaloma (group B) who were referred for putative hypercortisolism between 1 January 1993 and 1 January 2003. The 24-hour urinary free cortisol and post-dexamethasone plasma cortisol were measured. Accurate diagnosis of (absence of) Cushing's syndrome was confirmed by histopathological data and long-term follow-up. Based on the data obtained in group A, sensitivity, specificity and receiver operating characteristic (ROC) curves were calculated. RESULTS: Complete follow-up was obtained in 86%, and partial follow-up was obtained in 8% of patients. Median follow-up was 36 (1 to 122) months. In group A, 17 patients were found to have Cushing's syndrome. In this group median 24-hour urinary free cortisol was 77 (<5 to 51458) mmol/24 hours and median post-dexamethasone plasma cortisol was <50 (<50 to 4900) nmol/l. Area under the ROC curve was 0.958 for 24-hour urinary free cortisol and 0.985 for post-dexamethasone plasma cortisol. Optimal cut-off values were 180 nmol/24 hours (sensitivity 94%, specificity 94%) and 95 nmol/l (sensitivity 100%, specificity 94%) respectively. CONCLUSION: We established cut-off values for 24-hour free urinary cortisol excretion (180 nmol/24 hours) and for post-dexamethasone plasma cortisol (95 nmol/l) in the evaluation of patients referred for hypercortisolism. 相似文献