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71.
Pathophysiology of unstable angina. 总被引:2,自引:0,他引:2
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Safety of hepatitis C virus (HCV)‐treated donors for kidney transplantation excluding occult HCV infection through kidney biopsies 下载免费PDF全文
74.
Di Fiore F Lecleire S Antonietti M Savoye G Savoye-Collet C Hervé S Roque I Hochain P Ben Soussan E 《Endoscopy》2003,35(3):223-5; discussion 225
Delayed transpyloric impaction is a very rare complication of esophageal metallic stent placement. Authors report different endoscopic removal techniques, but none of these has been validated yet because of their variable success, time-consuming nature, and risk of perforation and hemorrhage. We report that a "wait-and-see" approach is a safe and effective policy in patients with permeable transpyloric impacted esophageal stents. 相似文献
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I. Sanz Pérez F. Martínez Valle A. Guillén-del-Castillo A. Roque Pérez H. Cuéllar Calàbria M.N. Pizzi A. Fernández Codina E. Callejas-Moraga O. Orozco Gálvez V. Fonollosa Pla C.P. Simeón Aznar 《Autoimmunity reviews》2018,17(9):900-905
Background and objectives
Recently published population-based cohort studies have shown a high prevalence of cardiovascular disease in Systemic Sclerosis (SSc) patients. The aim of this study is to compare three different methods to measure cardiovascular risk in patients with scleroderma.Methods
Forty-three SSc patients were included. A prospective study was performed for evaluation of cardiovascular risk and subclinical atheromatosis using 3 non-invasive methods: cardiovascular risk tables, carotid Doppler ultrasonography and quantification of coronary calcium by computerized tomography (CT).Results
The cardiovascular risk charts for the Spanish population did not identify patients at high cardiovascular risk. Framingham-REGICOR identified 13 intermediate-risk patients. Twenty-two patients (51.2%) had plaques on carotid ultrasonography. We performed a ROC curve to identify the best cutoff point for the quantification of coronary artery calcium (CACscore), the value of CACscore?>?28?AU (Agatston Units) had the highest sensitivity (73%) and specificity (81%) for the diagnosis of subclinical atheromatosis. In the multiple regression study, age and decreased HDL cholesterol levels were identified as independent factors for subclinical atherosclerotic disease. No disease-related factors were associated with increased subclinical arteriosclerosis.Conclusion
Carotid ultrasound and CACscore are useful for identifying subclinical atheromatosis in patients with SSc and are superior compared to risk charts used for general population. HDL cholesterol and age were independent factors for the presence of subclinical atherosclerotic disease. A carotid ultrasound or CT should be performed for early detection of subclinical atheromatosis if these factors are present. 相似文献76.
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José Vicente Negrete‐Díaz Eduardo Baltazar‐Gaytán María Elena Bringas Rubén Antonio Vazquez‐Roque Stephanie Newton Patricia Aguilar‐alonso Bertha Alicia León‐Chávez Gonzalo Flores 《Synapse (New York, N.Y.)》2010,64(12):941-947
Haloperidol is a potent dopamine receptor antagonist and used to treat psychotic disorders, such as schizophrenia. Recent clinical and preclinical studies demonstrated the overactivity of the nitric oxide (NO) system in schizophrenia. Neonatal ventral hippocampal (nVH) lesions in rats have been widely used as a neurodevelopmental model that mimics schizophrenia‐like behaviors. Here, we investigate first whether the nVH lesion causes changes in NO levels in different limbic brain regions in young adults, postnatal day (PD) 81, and second, whether haloperidol treatment from PD60 to PD81 reverses these changes, by determining the accumulation of nitrites. The results show that NO levels at the level of the prefrontal cortex, occipital cortex, and cerebellum are higher in the nVH lesion animals, and that the haloperidol, in part, attenuates these altered NO levels. The NO levels observed in the nVH lesion animals with and without haloperidol treatment may be relevant to behaviors observed in schizophrenia. Synapse 64:941–947, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
79.
A great challenge to clinical development is the delivery of chemotherapeutic agents, known to cause severe toxic effects, directly to diseased sites which increase the therapeutic index whilst minimizing off-target side effects. Antibody-conjugated nanoparticles offer great opportunities to overcome these limitations in therapeutics. They combine the advantages given by the nanoparticles with the ability to bind to their target with high affinity and improve cell penetration given by the antibodies. This specialized vehicle, that can encapsulate several chemotherapeutic agents, can be engineered to possess the desirable properties, allowing overcoming the successive physiological conditions and to cross biological barriers and reach a specific tissue or cell. Moreover, antibody-conjugated nanoparticles have shown the ability to be internalized through receptor-mediated endocytosis and accumulate in cells without being recognized by the P-glycoprotein, one of the main mediators of multi-drug resistance, resulting in an increase in the intracellular concentration of drugs. Also, progress in antibody engineering has allowed the manipulation of the basic antibody structure for raising and tailoring specificity and functionality. This review explores recent developments on active drug targeting by nanoparticles functionalized with monoclonal antibodies (polymeric micelles, liposomes and polymeric nanoparticles) and summarizes the opportunities of these targeting strategies in the therapy of serious diseases (cancer, inflammatory diseases, infectious diseases, and thrombosis). 相似文献
80.
The noninvasive early detection of specific matrix alterations in degenerative cartilage disease would be of substantial use in basic science studies and clinically, but remains an elusive goal. Recently developed MRI methods exhibit some specificity, but require contrast agents or nonstandard pulse sequences and hardware. We present a multiexponential approach which does not require contrast agents or specialized hardware, and uses a standard multiple‐echo spin‐echo sequence. Experiments were performed on tissue models of degenerative cartilage using enzymes with distinct actions. MR results were validated using histologic, biochemical and infrared spectroscopic analyses. The sulfated glycosaminoglycan per dry weight (dw) in bovine nasal cartilage was 0.72 ± 0.06 mg/mg dw and was reduced through chondroitinase AC and collagenase digestion to 0.56 ± 0.12 and 0.58 ± 0.13 mg/mg dw, respectively. Multiexponential analysis of data obtained at 9.4 T permitted the identification of tissue compartments assigned to the proteoglycan component of the matrix and to bulk water. Enzymatic treatment resulted in a significant reduction in the ratio of proteoglycan‐bound to free water from 0.13 ± 0.02 in control cartilage to 0.03 ± 0.02 and 0.05 ± 0.06 under chondroitinase AC and collagenase treatment, respectively. As expected, monoexponential T2 increased with both degradation protocols, but without further specificity to the nature of the degradation. An important eventual extension of this approach may be to map articular cartilage degeneration in the clinical setting. As an initial step towards this, localized multiexponential T2 analysis was performed on control and trypsin treated excised bovine patella. The results obtained on this articular cartilage sample were readily interpretable in terms of proteoglycan‐associated and relatively free water compartments. In potential clinical applications, signal‐to‐noise ratio constraints will define the threshold for the detection of macromolecular compartment changes at a given spatial scale. The multiexponential approach has potential application to the early detection of cartilage degradation with the use of appropriate pulse parameters under high signal‐to‐noise ratio conditions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献