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991.
992.
Several investigators have reported the correlation of p53 and bcl-2 immunoreactivity with post operative prostate specific antigen (PSA) recurrence. Focal and or clustered expression is typical for these biomarkers. The purpose of this study was to compare the effectiveness of tissue microarrays to detect p53 and bcl-2 overexpression and their prognostic significance. Tissue microarrays (TMA) of 99 patients with mean follow-up of 61 months contained 760 samples from 241 carcinomas, 431 benign glands, and 88 foci of prostatic intraepithelial neoplasia (PIN). Overexpression of p53 was seen in 43.3% of 97 patients, whereas bcl-2 overexpression was noted in 23.7% of 97 patients using TMA technology, compared to 66.0% and 26.9%, respectively in the corresponding radical prostatectomy samples. The tissue microarray technology is a powerful tool to study the multifocal and heterogeneous nature of prostate cancer. However, the prognostic value of p53 and bcl-2 could not be confirmed using this technology in contrast to radical prostatectomy sections. The TMA technique is probably more informative and reliable in evaluating the prognostic value of homogeneously expressed biomarkers.  相似文献   
993.
Stejskal and Tanner's ingenious pulsed field gradient design from 1965 has made diffusion NMR and MRI the mainstay of most studies seeking to resolve microstructural information in porous systems in general and biological systems in particular. Methods extending beyond Stejskal and Tanner's design, such as double diffusion encoding (DDE) NMR and MRI, may provide novel quantifiable metrics that are less easily inferred from conventional diffusion acquisitions. Despite the growing interest on the topic, the terminology for the pulse sequences, their parameters, and the metrics that can be derived from them remains inconsistent and disparate among groups active in DDE. Here, we present a consensus of those groups on terminology for DDE sequences and associated concepts. Furthermore, the regimes in which DDE metrics appear to provide microstructural information that cannot be achieved using more conventional counterparts (in a model‐free fashion) are elucidated. We highlight in particular DDE's potential for determining microscopic diffusion anisotropy and microscopic fractional anisotropy, which offer metrics of microscopic features independent of orientation dispersion and thus provide information complementary to the standard, macroscopic, fractional anisotropy conventionally obtained by diffusion MR. Finally, we discuss future vistas and perspectives for DDE. Magn Reson Med 75:82–87, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   
994.
Hart JP  Peeters P  Verbist J  Deloose K  Bosiers M 《Journal of vascular surgery》2006,44(4):725-30; discussion 730-1
OBJECTIVES: The study was conducted to identify patient and procedural parameters that negatively impact the 30-day rates for stroke, death and transient ischemic attack (TIA) after carotid artery stenting (CAS) and that might be modified or further studied in future efforts to improve CAS. METHODS: This was a retrospective investigation of a dual-center CAS database of 701 consecutive CAS patients (414 men; mean age, 72.4 +/- 8.4). A subset of patient-related, lesion-related, or procedure-related variables (age >or=80, left sided lesion, symptomatic, nicotine abuse, hypertension, diabetes mellitus, other peripheral vascular disease, hypercholesterolemia, embolic protection devices usage, predilation, ulcerated lesion, echolucent plaque, restenosis after surgery) were analyzed for association with occurrence of stroke, death, or TIA 相似文献   
995.
996.
Polyarteritis nodosa (PAN) is a medium vessels vasculitis variously involving different organs and systems, sometimes with an aggressive course, leading to death or disability in a significant number of cases. First-line treatment usually relies on steroids and classical immunosuppressants, but a growing number of case reports and small case series shows the potential role of biologic drugs, mostly anti-tumor necrosis factor (TNF)-α agents, in inducing and maintaining remission in patients affected by PAN. Similarly, the recently described autoinflammatory disease named deficit of adenosine deaminase 2 (DADA2), considered by several experts as a more precocious and aggressive variant of PAN, seems to respond to a prompt treatment with TNF-α inhibitors. The aim of this review is to collect all existing evidences about the use of biologic drugs in PAN and DADA2. Fifty-one articles published during the last 15 years were retrieved, including 58 and 76 patients affected by PAN and DADA2, respectively, and treated with biologic drugs. The majority of subjects was treated with TNF-α inhibitors, whose effectiveness was reported in the treatment of such difficult-to-manage diseases, particularly in DADA2. Among the other biologic drugs, Tocilizumab was successfully employed in some subjects affected by PAN who did not respond to TNF-α inhibitors, while Rituximab did not give substantial benefits neither in PAN nor in DADA2. Only few data exist about the role of Janus-kinase inhibitors and anti-IL1 agents.This study provides the first comprehensive assessment of biologic agents in both PAN and DADA2, with encouraging results especially in the context of TNF-α inhibitors. Nevertheless, due to the lack of prospective, randomized, case control studies, further efforts should be made in order to fully elucidate the role of these drugs in such rare and life-threatening conditions.  相似文献   
997.
 The aim of this study was to determine locations and morphologies of enteric neurons innervating the small intestinal mucosa of the pig after application of the carbocyanine tracer DiI onto a single villus. The tissue was processed in two ways: incubation (1) of fixed material (postmortem tracing) for several months and (2) of living specimens within organotypic culture in vitro for several days (supravital tracing). In both procedures DiI-labelled neurons were found in the three ganglionated plexuses, the internal and external submucous plexus as well as the myenteric plexus. Postmortem tracing revealed different neuronal morphologies. Adendritic type II neurons were present in all three plexuses, type IV neurons with short, scarcely branched, polarly emerging dendrites were mainly found in the myenteric plexus and small dendritic neurons were mainly present in the internal submucous plexus. The latter may correspond to minineurons hitherto described only immunohistochemically. Tracing within tissue culture showed somata of neurons and, partly, proximal segments of processes to be labelled. Subsequent immunohistochemistry using general neuronal markers revealed some neurons to be adendritic type II neurons. Visualization of dendrites was less clear, hampering an accurate morphological classification of dendritic neurons. Our results suggest that neurons of all ganglionated enteric nerve plexuses of the pig participate in the innervation of the mucosa, and that postmortem tracing revealed enteric neuronal morphology more clearly than supravital tracing. Since the former method cannot be applied for deciphering the chemical coding of enteric neurons, combination of both methods will extend our knowledge of the morphological substrate for the intrinsic neuronal microcircuits in the gastrointestinal tract. Accepted: 15 July 1998  相似文献   
998.
There is a growing interest in using dendritic cells (DC) for vaccine approaches in the treatment of cancer and infectious diseases. This requires a reproducible method for the generation of large numbers of DC in a closed culture system suitable for clinical use and conforming to the current guidelines of good manufacturing practices.We designed a system in which the DC were generated in a closed system from adherent monocytes using Cell Factories (DC-CF). Monocytes were enriched from apheresis products by adherence and then cultured in the presence of AB serum or autologous plasma and GM-CSF and IL-4 for 6 days. The DC generated in Cell Factories were extensively compared to research-grade DC generated in conventional tissue culture flasks (DC-TCF). At day 6, the immature DC were harvested and the yield, the viability, the immunophenotype and the functional characteristics of the DC were compared.DC-CF and DC-TCF showed similar viability and purity and scored equally when tested for stability, dextran and latex bead uptake, in MLR and in the activation of influenza-specific memory cells after electroporation with influenza matrix protein 1 (IMP1) mRNA.These data indicated that large numbers of functional clinical-grade DC could be generated from adherent cells in a closed system using Cell Factories.  相似文献   
999.
Allergic asthma is a frequent asthma phenotype. Both IgE and type 2 cytokines are increased, with some degree of overlap with other phenotypes. Systematic reviews assessed the efficacy and safety of benralizumab, dupilumab and omalizumab (alphabetical order) vs standard of care for patients with uncontrolled severe allergic asthma. PubMed, Embase and Cochrane Library were searched to identify RCTs and health economic evaluations, published in English. Critical and important asthma-related outcomes were evaluated. The risk of bias and the certainty of the evidence were assessed using GRADE. All three biologicals reduced with high certainty the annualized asthma exacerbation rate: benralizumab incidence rate ratios (IRR) 0.63 (95% CI 0.50 − 0.81); dupilumab IRR 0.58 (95%CI 0.47 − 0.73); and omalizumab IRR 0.56 (95%CI 0.42 − 0.73). Benralizumab and dupilumab improved asthma control with high certainty and omalizumab with moderate certainty; however, none reached the minimal important difference (MID). Both benralizumab and omalizumab improved QoL with high certainty, but only omalizumab reached the MID. Omalizumab enabled ICS dose reduction with high certainty. Benralizumab and omalizumab showed an increase in drug-related adverse events (AEs) with low to moderate certainty. All three biologicals had moderate certainty for an ICER/QALY value above the willingness to pay threshold. There was high certainty that in children 6-12 years old omalizumab decreased the annualized exacerbation rate [IRR 0.57 (95%CI 0.45-0.72)], improved QoL [relative risk 1.43 (95%CI 1.12 −1.83)], reduced ICS [mean difference (MD) −0.45 (95% CI −0.58 to −0.32)] and rescue medication use [ MD −0.41 (95%CI −0.66 to −0.15)].  相似文献   
1000.
Purpose We aimed to determine the composition of radioactivity in rat brain after intravenous administration of the dopamine transporter radioligand, [11C]PE2I. Methods PET time-activity curves (TACs) and regional brain distribution ex vivo were measured using no-carrier-added [11C]PE2I. Carrier-added [11C]PE2I was administered to identify metabolites with high-performance liquid radiochromatography (RC) or RC with mass spectrometry (LC-MS and MS-MS). The stability of [11C]PE2I was assessed in rat brain homogenates. Results After peak brain uptake of no-carrier-added [11C]PE2I, there was differential washout rate from striata and cerebellum. Thirty minutes after injection, [11C]PE2I represented 10.9 ± 2.9% of the radioactivity in plasma, 67.1 ± 11.0% in cerebellum, and 92.5 ± 3.2% in striata, and was accompanied by two less lipophilic radiometabolites. [11C]PE2I was stable in rat brain homogenate for at least 1 h at 37°C. LC-MS identified hydroxylated PE2I (1) (m/z 442) and carboxyl-desmethyl-PE2I (2) (m/z 456) in brain. MS-MS of 1 gave an m/z 442→424 transition due to H2O elimination, so verifying the presence of a benzyl alcohol group. Metabolite 2 was the benzoic acid derivative. Ratios of ex vivo measurements of [11C]PE2I, [11C]1, and [11C]2 in striata to their cognates in cerebellum were 6.1 ± 3.4, 3.7 ± 2.2 and 1.33 ± 0.38, respectively, showing binding selectivity of metabolite [11C]1 to striata. Conclusion Radiometabolites [11C]1 and [11C]2 were characterized as the 4-hydroxymethyl and 4-carboxyl analogs of [11C]PE2I, respectively. The presence of the pharmacologically active [11C]1 and the inactive [11C]2 is a serious impediment to successful biomathematical analysis.  相似文献   
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