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排序方式: 共有2624条查询结果,搜索用时 234 毫秒
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Win AK Walters RJ Buchanan DD Jenkins MA Sweet K Frankel WL de la Chapelle A McKeone DM Walsh MD Clendenning M Pearson SA Pavluk E Nagler B Hopper JL Gattas MR Goldblatt J George J Suthers GK Phillips KD Woodall S Arnold J Tucker K Field M Greening S Gallinger S Aronson M Perrier R Woods MO Green JS Walker N Rosty C Parry S Young JP 《The American journal of gastroenterology》2012,107(5):770-778
73.
Mutlak D Lessick J Carasso S Kapeliovich M Dragu R Hammerman H Agmon Y Aronson D 《The American journal of cardiology》2012,109(9):1254-1259
Pulmonary hypertension (PH) is usually perceived as a complication of established heart failure (HF) rather than as a predictor of HF or a marker of subclinical HF. PH may develop because of cardiac alterations that result in increased filling pressures after acute myocardial infarction (AMI). We hypothesized that PH might be a useful marker to predict the risk of HF after AMI. We studied 1,054 patients with AMI. Pulmonary artery systolic pressure (PASP) was estimated using echocardiography at the index admission and PH was defined as a PASP >35 mm Hg. The primary end point was readmission for HF at 1 year. PH was present in 471 patients (44.6%) and was strongly associated with age, decreased ejection fraction, advanced diastolic dysfunction, and moderate/severe mitral regurgitation (p <0.0001 for all comparisons). Area under the receiver operating characteristic curve was significantly higher for estimated PASP (0.74 ± 0.02) compared to other echocardiographic parameters (p = 0.02 to 0.0003). After adjustments for clinical and echocardiographic variables in a Cox model, PH was associated with a hazard ratio of 3.10 for HF (95% confidence interval 1.31 to 2.57, p <0.0001). After adding estimated PASP to a model containing clinical and echocardiographic risk factors, net reclassification improvement was 0.21 (95% confidence interval 0.11 to 0.31, p <0.0001). In conclusion, PASP integrates the severity of multiple hemodynamic determinants of increased left atrial pressures that lead to an increase in pulmonary venous pressure. In AMI, PH at the index admission is a useful marker in unmasking latent subclinical HF and predicting the development of overt HF. 相似文献
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Myeloma is a malignancy of the antibody-producing plasma cells and, as such, these cells synthesize large quantities of unfolded or misfolded immunoglobulin. The build-up of excess protein triggers a number of downstream signal transduction cascades, including endoplasmic reticulum stress and autophagy. As a result, myeloma cells are uniquely reliant on these and other protein handling pathways for their survival. Strategies aimed at targeting this vulnerability have proved successful with the proteasome inhibitor, bortezomib, already licensed for clinical use. In addition to the proteasome, various other points within the protein handling pathways are also the subject of drug discovery projects, with some already progressing into clinical trials. These include compounds directed against heat shock proteins, the unfolded protein response and pathways both upstream and downstream of the proteasome. More recently, the role of autophagy has been recognized in myeloma. In this review, we discuss the various pathways used by myeloma cells for survival, with particular emphasis on the emerging role and conundrum of autophagy, as well as highlighting pre-clinical research on novel inhibitors targeting protein handling pathways. 相似文献
76.
AS Winkler K Friedrich S Velicheti J Dharsee R K?nig A Nassri M Meindl A Kidunda TH Müller L Jilek-Aall W Matuja T Gotwald E Schmutzhard 《African health sciences》2013,13(2):529-540
Background
Onchocerciasis has been implicated in the pathogenesis of epilepsy. The debate on a potential causal relationship between Onchocerca volvulus and epilepsy has taken a new direction in the light of the most recent epidemic of nodding syndrome.Objective
To document MRI changes in people with different types of epilepsy and investigate whether there is an association with O. volvulus infection.Methods
In a prospective study in southern Tanzania, an area endemic for O. volvulus with a high prevalence of epilepsy and nodding syndrome, we performed MRI on 32 people with epilepsy, 12 of which suffered from nodding syndrome. Polymerase chain reaction (PCR) of O. volvulus was performed in skin and CSF.Results
The most frequent abnormalities seen on MRI was atrophy (twelve patients (37.5%)) followed by intraparenchymal pathologies such as changes in the hippocampus (nine patients (28.1%)), gliotic lesions (six patients (18.8%)) and subcortical signal abnormalities (three patients (9.4%)). There was an overall trend towards an association of intraparenchymal cerebral pathologies and infection with O. volvulus based on skin PCR (Fisher''s Exact Test p=0.067) which was most pronounced in children and adolescents with nodding syndrome compared to those with other types of epilepsy (Fisher''s Exact Test, p=0.083). Contrary to skin PCR results, PCR of CSF was negative in all patients.Conclusion
The observed trend towards an association of intraparenchymal cerebral pathological results on MRI and a positive skin PCR for O. volvulus despite negative PCR of CSF is intriguing and deserves further attention. 相似文献77.
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Sean C. Skeldon Kara Semotiuk Melyssa Aronson Spring Holter Steven Gallinger Aaron Pollett Cynthia Kuk Bas van Rhijn Peter Bostrom Zane Cohen Neil E. Fleshner Michael A. Jewett Sally Hanna Shahrokh F. Shariat Theodorus H. Van Der Kwast Andrew Evans Jim Catto Bharati Bapat Alexandre R. Zlotta 《European urology》2013