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排序方式: 共有9577条查询结果,搜索用时 31 毫秒
91.
Teresa Trenkwalder Anna Lena Lahmann Magdalena Nowicka Costanza Pellegrini Tobias Rheude N. Patrick Mayr Stephanie Voss Sabine Bleiziffer Rüdiger Lange Michael Joner Albert M. Kasel Adnan Kastrati Heribert Schunkert Oliver Husser Martin Hadamitzky Christian Hengstenberg 《The international journal of cardiovascular imaging》2018,34(6):985-992
Multislice computed tomography (MSCT) has emerged as the mainstay in patients planned for transcatheter aortic valve implantation (TAVI). Incidental findings (IF) in MSCT are common. However, the exact incidence, clinical relevance and further consequences of IF are unclear and it is controversial whether IF adversely affect patients’ outcome. We analyzed MSCT data of 1050 patients screened for TAVI between January 2011 and December 2014. Median follow-up of patients was 20 months. In total, 3194 IF were identified, which were classified into clinically non-relevant IF (2872, 90%) and clinically relevant IF (322, 10%). In 25% of patients (258/1050) at least one clinically relevant IF was present. Age (80?±?7 vs. 80?±?7 years; p?=?0.198) and EuroSCORE II (3.6% [2.1–5.7] vs. 3.6% [2.1–5.9]; p?=?0.874) was similar between patients with and without a clinically relevant IF. TAVI was performed less frequently in patients with a clinically relevant IF (76% vs. 85%; p?<?0.001), with more patients receiving surgical aortic valve replacement in that group (14% vs. 11%; p?=?0.042), possibly due to the high rate of incidental aneurysms of the ascending aorta (n?=?48). If TAVI was performed mortality did not differ (30-days: 4% vs. 3%; p?=?0.339, 1-year: 11% vs. 14%; p?=?0.226) between patients with and without a clinically relevant IF. Our study is the largest study to analyze prevalence, clinical relevance and therapeutic consequences of IF during screening for TAVI. IF in pre-procedural MSCT are common and clinically relevant in one-quarter of patients. However, these findings had no impact on overall mortality. 相似文献
92.
93.
Measurement of Serum Electrolytes and Phosphate After Sodium Phosphate Colonoscopy Bowel Preparation: An Evaluation 总被引:3,自引:0,他引:3
Our purpose was to observe the effects of sodium phosphate (NaP) colonoscopy preparation on serum electrolytes, phosphate, and calcium and to identify factors associated with any adverse effects. In an unselected group of 100 consecutive patients attending for out patient colonoscopy, 45% of patients had raised serum phosphate, which was positively correlated with creatinine and age. There was a negative association of phosphate with calcium; 16% of patients had hypocalcemia and 26% had hypokalemia. Patients taking ACE inhibitors, AT2 antagonists, or diuretics were associated with hyperphosphatemia. Significant electrolyte and metabolic disturbance from colonoscopy preparation has been shown with NaP preparation, without overt clinical effects. We recommend that elderly patients and those with significant comorbidity have their electrolytes and calcium measured, and diuretics and ACE inhibitors stopped, before NaP administration. Endoscopy units should be alert for patients who might be suffering from electrolyte disturbance postpreparation and be prepared to measure their electrolytes. 相似文献
94.
Van Thiel DH George M Brems J Holt D Zhu Q Edelstein S Amiral J Tarasuk G Leone N 《The American journal of gastroenterology》2003,98(2):460-465
OBJECTIVE: The aim of this study was to determine whether liver transplantation of patients with antiphospholipid antibodies (APA) is 1) adversely affected with vascular thrombosis and 2) whether such antibodies persist post transplantation. METHODS: Twelve patients with APA awaiting transplant were identified and characterized biochemically and immunologically. Each had the level of APA determined using commercially available enzyme-linked immunoassay kits before, during, and after liver transplantation. RESULTS: No patient in this series experienced a transplant-related vascular thrombosis. The titer of APA fell to levels at or below those present in normals and remained low in two of 12 or undetectable in 10 of 12 patients 1 yr after liver transplantation. CONCLUSIONS: We reached the following conclusions: 1) Antiphospholipid positivity does not identify patients at high risk for post-transplant vascular thrombosis. 2) The levels of antiphospholipid present in sera pretransplant fell during transplantation and remained low or undetectable 1 month and 1 yr post transplantation. 相似文献
95.
Socio-demographic, behavioral, functional and anthropometric data for groups of elderly Quechua Indians of Peru were used
to investigate the effects of gender and lifestyle patterns on nutritional status. Two community-dwelling samples were selected
for study, representative of divergent lifestyles in terms of their combination of socio-economic, demographic and cultural
contexts, plus an ad-hoc sample of institutionalized individuals with controlled food intake and reduced physical activity. Results suggest that differences
in socio-demographic, behavioral and functional characteristics exist between the sexes and across settings (low- vs. highland)
and lifestyles (institutionalized vs. community-dwelling; semi-urban vs. rural). These factors are likely to be related to
diverging dietary and physical activity patterns, and have considerable effects on the nutritional status of the respondents. 相似文献
96.
Hurlstone DP Shorthouse AJ Cross SS Brown S Sanders DS Lobo AJ 《Techniques in coloproctology》2004,8(3):173-178
Abstract
Background
Persistence of underlying disease in the residual rectal mucosa and anal transition zone (ATZ) following ileal pouch-anal anastomosis (IPAA) for ulcerative colitis and familial adenomatous polyposis provides a site for potential malignancy. For this reason endoscopic surveillance is performed, although conventional assessment may be unreliable. We hypothesized that the novel technique of high-magnification chromoscopic pouchoscopy (HMCP) may permit accurate anatomical localization of this high risk zone in vivo and permit improved biopsy accuracy.
Patients and methods
We studied 132 patients with IPAA using HMCP. Three distinct zones were defined using magnification endoscopy: ATZ, appearing as a linear cellular marix; columnar cuff, identifiable by a type I crypt pattern; and ileal pouch body, appearing as villous projections. Quadrantic biopsies of these zones were taken in addition to biopsies of any other lesions noted.
Results
A total of 1586 biopsies were taken from zones 1–3 (median, 12; range, 5–16 per patient). Overall biopsy-targeting accuracies using magnification guidance as compared with histopathology were 82%, 73% and 91% for the ATZ, cuff and pouch body, respectively. No dysplasia was identified in the quadrantic surveillance biopsies. Histologically confirmed columnar metaplasia was visualized in vivo using magnification chromoscopy. Patients with IPAA >3 years duration were more likely to have pouch reservoir columnar metaplasia as compared to those <3 years (p<0.01). Pouch reservoir metaplasia was associated with a pre-morbid diagnosis of high-grade dysplasia or carcinoma within the premorbid colectomy specimen (p<0.001).
Conclusions
This is the first study to evaluate this novel application of high magnification chromoscopy. Magnification pouchoscopy is a valid predictor of ATZ and cuff anatomy, permitting accurate biopsy targeting. Further randomized studies validating this technique with an emphasis on dysplasia detection in larger cohorts are required. 相似文献
97.
Cornelia Speth Gerhard Blum Magdalena Hagleitner Caroline Hörtnagl Kristian Pfaller Beate Posch Helmut Werner Ott Reinhard Würzner Cornelia Lass-Flörl Günter Rambach 《Medical microbiology and immunology》2013,202(5):379-389
Aspergillus terreus-induced invasive infections exhibit high lethality, partly due to the intrinsic resistance for amphotericin B (AmB). We compared the virulence and pathogenesis of an AmB-resistant isolate of A. terreus (ATR) with that of a rare variant showing enhanced sensitivity for AMB (ATS). The modifications that result in enhanced AmB sensitivity of isolates are not associated with reduced virulence in vivo; instead, the ATS-infected mice died even faster than the ATR-infected animals. Since A. terreus enters the blood stream in most patients and frequently induces thrombosis, we studied a putative correlation between virulence of the two A. terreus isolates and their effect on thrombocytes. Those mice infected with the more virulent ATS isolate had lower thrombocyte numbers and more phosphatidylserine exposure on platelets than ATR-infected mice. In vitro experiments confirmed that ATS and ATR differ in their effect on thrombocytes. Conidia, aleurioconidia and hyphae of ATS were more potent than ATR to trigger thrombocyte stimulation, and thrombocytes adhered better to ATS than to ATR fungal structures. Furthermore, ATS secreted more soluble factors that triggered platelet stimulation than ATR. Thus, it might be suggested that the capacity of a fungal isolate to modulate thrombocyte parameters contributes to its virulence in vivo. 相似文献
98.
Loukia Katsouri Marcela P. Vizcaychipi Simon McArthur Ian Harrison Marc Suárez-Calvet Alberto Lleo Dafydd G. Lloyd Daqing Ma Magdalena Sastre 《Neurobiology of aging》2013
Noradrenergic deficits have been described in the hippocampus and the frontal cortex of Alzheimer's disease brains, which are secondary to locus coeruleus degeneration. Locus coeruleus is the brain stem nucleus responsible for synthesis of noradrenaline and from where all noradrenergic neurons project. In addition, it has been suggested that noradrenaline might play a role in modulating inflammatory responses in Alzheimer's disease. In this study we aimed to investigate the effect of various agonists and antagonists for adrenergic receptors on amyloid precursor protein processing. Among them, we found that prazosin, an α1-adrenoceptor antagonist, was able to reduce the generation of amyloid β in N2a cells. Treatment of transgenic APP23 mice with prazosin prevented memory deficits over time. Although prazosin did not influence amyloid plaque load, it induced astrocytic proliferation and increased the release of apolipoprotein E and anti-inflammatory cytokines. These findings suggest that chronic treatment with prazosin leads to an anti-inflammatory response with potential beneficial effects on cognitive performance. 相似文献
99.
100.