977 resultados para Persistent
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PURPOSE: To describe methods and outcomes of excisional revision of a filtering bleb (bleb revision) using free conjunctival autologous graft either for bleb repair or for bleb reduction after trabeculectomy and deep sclerectomy with an implant. METHODS: Retrospective medical records were reviewed for a consecutive non-comparative case series comprising patients who underwent excisional revision of a filtering bleb between May 1998-January 2001. Excisional revision using free conjunctival autologous graft (bleb revision) was performed either for bleb repair, to treat early and late leaks and hypotony with maculopathy, or for bleb reduction, to improve ocular pain, discomfort, burning, foreign body sensation, tearing, and fluctuations of visual acuity. The revision consisted of bleb excision and free conjunctival autologous graft. The bleb histopathology was analyzed in patients who underwent bleb repair. RESULTS: Sixteen patients were included in the study, consisting of nine patients who had a trabeculectomy and seven patients who had a deep sclerectomy with an implant. Bleb revision was necessary in 14 patients due to leaking filtering bleb (bleb repair), and in 2 patients due to bleb dysesthesia (bleb reduction). After a follow-up of 15.1 +/- 8.4 months, the mean intraocular pressure (IOP) rose from 7.8 +/- 6.3 mm Hg to 14.3 +/- 6.5 mm Hg, and the visual acuity from 0.4 +/- 0.3 to 0.7 +/- 0.3, with a P value of 0.008 and 0.03, respectively. The complete success rate at 32 months, according to the Kaplan-Meier survival curve, was 38.3%, and the qualified success rate was 83.3%. Four patients (25%) required additional suturing for persistent bleb leak. To control IOP, antiglaucoma medical therapy was needed for six patients (37.5%) and repeated glaucoma surgery was needed for one patient. CONCLUSION: Free conjunctival autologous graft is a safe and successful procedure for bleb repair and bleb reduction. However, patients should be aware of the postoperative possibility of requiring medical or surgical intervention for IOP control after revision.
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All derivations of the one-dimensional telegraphers equation, based on the persistent random walk model, assume a constant speed of signal propagation. We generalize here the model to allow for a variable propagation speed and study several limiting cases in detail. We also show the connections of this model with anomalous diffusion behavior and with inertial dichotomous processes.
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Soil compaction has been recognized as a severe problem in mechanized agriculture and has an influence on many soil properties and processes. Yet, there are few studies on the long-term effects of soil compaction, and the development of soil compaction has been shown through a limited number of soil parameters. The objectives of this study were to evaluate the persistence of soil compaction effects (three traffic treatments: T0, without traffic; T3, three tractor passes; and T5, five tractor passes) on pore system configuration, through static and dynamic determinations; and to determine changes in soil pore orientation due to soil compaction through measurement of hydraulic conductivity of saturated soil in samples taken vertically and horizontally. Traffic led to persistent changes in all the dynamic indicators studied (saturated hydraulic conductivity, K0; effective macro- and mesoporosity, εma and εme), with significantly lower values of K0, εma, and εme in the T5 treatment. The static indicators of bulk density (BD), derived total porosity (TP), and total macroporosity (θma) did not vary significantly among the treatments. This means that machine traffic did not produce persistent changes on these variables after two years. However, the orientation of the soil pore system was modified by traffic. Even in T0, there were greater changes in K0 measured in the samples taken vertically than horizontally, which was more related to the presence of vertical biopores, and to isotropy of K0 in the treatments with machine traffic. Overall, the results showed that dynamic indicators are more sensitive to the effects of compaction and that, in the future, static indicators should not be used as compaction indicators without being complemented by dynamic indicators.
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Many genes have evolved sexually dimorphic expression as a consequence of divergent selection on males and females. However, because the sexes share a genome, the extent to which evolution can shape gene expression independently in each sex is controversial. Here, we use experimental evolution to reveal suboptimal sex-specific expression for much of the genome. By enforcing a monogamous mating system in populations of Drosophila melanogaster for over 100 generations, we eliminated major components of selection on males: female choice and male-male competition. If gene expression is subject to sexually antagonistic selection, relaxed selection on males should cause evolution towards female optima. Monogamous males and females show this pattern of feminization in both the whole-body and head transcriptomes. Genes with male-biased expression patterns evolved decreased expression under monogamy, while genes with female-biased expression evolved increased expression, relative to polygamous populations. Our results demonstrate persistent and widespread evolutionary tension between male and female adaptation.
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A markedly elevated circulating CEA level was observed in January 1978 in a 40-year-old male patient who complained of functional digestive disorders consisting of 2-3 bowel movements at the end of each night. During follow-up of more than 3 years the CEA level was always found to be higher than 300 ng/ml as determined on 12 different blood samples using 3 different assays: the Hansen assay, our own inhibition radioimmunoassay performed on perchloric acid extract of serum, and a newly developed solid phase non-competitive enzyme immunoassay involving monoclonal anti-CEA antibody. The clinical evolution showed no aggravation of the persistent but mild bowel troubles, i.e. no real diarrhea or blood in the stool. The patient enjoys excellent general health and shows no weight loss. Barium enema, colonoscopy and extensive investigation by computerized axial tomography showed no evidence of primary or metastatic tumor. Apart from CEA, the blood chemistry was within normal limits. Six members of the patient's family have normal CEA levels. A possible explanation for this unique case of marked and persistent elevation of circulating CEA without evidence of cancer is discussed.
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ABSTRACT Persistent areas of tailings and deposits from coal and gold mining may present high levels of arsenic (As), mainly in the arsenate form, endangering the environment and human health. The establishment of vegetation cover is a key step to reclaiming these environments. Thus, this study aimed to evaluate the potential of Eucalyptus urophylla and E. citriodora seedlings for use in phytoremediation programs of arsenate-contaminated areas. Soil samples were incubated at increasing rates (0, 50, 100, 200 and 400 mg dm-3) of arsenic (arsenate form, using Na2HAsO4) for 15 days. The seedlings were produced in a substrate (vermiculite + sawdust) and were transplanted to the pots with soil three months after seed germination. The values of plant height and diameter were taken during transplanting and 30, 60 and 90 days after transplanting. In the last evaluation, the total leaf area and biomass of shoots and roots were also determined. The values of available As in soil which caused a 50 % dry matter reduction (TS50%), the As translocation index (TI) from the roots to the shoot of the plants, and its bioconcentration factor (BF) were also calculated. Higher levels of arsenate in the soil significantly reduced the dry matter production of roots and shoots and the height of both species, most notably in E. urophylla plants. The highest levels of As were found in the root, with higher values for E. citriodora (ranging from 253.86 to 400 mg dm-3). The TI and BF were also reduced with As doses, but the values found in E. citriodora were significantly higher than in E. urophylla. E. citriodora plants presented a higher capacity to tolerate As and translocate it to the shoot than E. urophylla. Although these species cannot be considered as hyperaccumulators of As, E. citriodora presented the potential to be used in phytoremediation programs in arsenate-contaminated areas due to the long-term growth period of this species.
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We analysed the specific case of how information in the financial press influences economic bubbles. We found considerable flaws in the information market due to several factors: demand, the predominance of what are termed “irrational investors” (herding), and supply, which has the problem that the sources of information are biasedand feeds. A financial bubble is a deviation between real value of a financial asset and its persistent market price in time, which also has a speculative origin fed back by the illusion of the owners of these financial values, who will take benefits because of the future prices, which must be higher than the previous ones. The economical information in the media is submitting three problems. First of all, it is information generated by companies. In second place, the information circuit is fed back. A problem of informative independence becomes created, particularly serious in the case of the banks, which are very were as creditors. And in a third place, some informative biases are manifested for the companies of regulated sectors which are starring the economical information in the media.
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BACKGROUND AND PURPOSE: This study aims to determine whether perfusion computed tomographic (PCT) thresholds for delineating the ischemic core and penumbra are time dependent or time independent in patients presenting with symptoms of acute stroke. METHODS: Two hundred seventeen patients were evaluated in a retrospective, multicenter study. Patients were divided into those with either persistent occlusion or recanalization. All patients received admission PCT and follow-up imaging to determine the final ischemic core, which was then retrospectively matched to the PCT images to identify optimal thresholds for the different PCT parameters. These thresholds were assessed for significant variation over time since symptom onset. RESULTS: In the persistent occlusion group, optimal PCT parameters that did not significantly change with time included absolute mean transit time, relative mean transit time, relative cerebral blood flow, and relative cerebral blood volume when time was restricted to 15 hours after symptom onset. Conversely, the recanalization group showed no significant time variation for any PCT parameter at any time interval. In the persistent occlusion group, the optimal threshold to delineate the total ischemic area was the relative mean transit time at a threshold of 180%. In patients with recanalization, the optimal parameter to predict the ischemic core was relative cerebral blood volume at a threshold of 66%. CONCLUSIONS: Time does not influence the optimal PCT thresholds to delineate the ischemic core and penumbra in the first 15 hours after symptom onset for relative mean transit time and relative cerebral blood volume, the optimal parameters to delineate ischemic core and penumbra.
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Background Patients with cirrhosis in ChildPugh class C or those in class B who have persistent bleeding at endoscopy are at high risk for treatment failure and a poor prognosis, even if they have undergone rescue treatment with a transjugular intrahepatic porto - systemic shunt (TIPS). This study evaluated the earlier use of TIPS in such patients. Methods We randomly assigned, within 24 hours after admission, a total of 63 patients with cirrhosis and acute variceal bleeding who had been treated with vasoactive drugs plus endoscopic therapy to treatment with a polytetrafluoroethylene-covered stent within 72 hours after randomization (early-TIPS group, 32 patients) or continuation of vasoactive-drug therapy, followed after 3 to 5 days by treatment with propranolol or nadolol and long-term endoscopic band ligation (EBL), with insertion of a TIPS if needed as rescue therapy (pharmacotherapyEBL group, 31 patients). Results During a median follow-up of 16 months, rebleeding or failure to control bleeding occurred in 14 patients in the pharmacotherapyEBL group as compared with 1 patient in the early-TIPS group (P=0.001). The 1-year actuarial probability of remaining free of this composite end point was 50% in the pharmacotherapyEBL group versus 97% in the early-TIPS group (P<0.001). Sixteen patients died (12 in the pharmacotherapyEBL group and 4 in the early-TIPS group, P=0.01). The 1-year actuarial survival was 61% in the pharmacotherapyEBL group versus 86% in the early-TIPS group (P<0.001). Seven patients in the pharmacotherapyEBL group received TIPS as rescue therapy, but four died. The number of days in the intensive care unit and the percentage of time in the hospital during follow-up were significantly higher in the pharmacotherapyEBL group than in the early-TIPS group. No significant diferences were observed between the two treatment groups with respect to serious adverse events. Conclusions In these patients with cirrhosis who were hospitalized for acute variceal bleeding and at high risk for treatment failure, the early use of TIPS was associated with signif icant reductions in treatment failure and in mortality. (Current Controlled Trials number, ISRCTN58150114.)
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During chronic infection, pathogen-specific CD8(+) T cells upregulate expression of molecules such as the inhibitory surface receptor PD-1, have diminished cytokine production and are thought to undergo terminal differentiation into exhausted cells. Here we found that T cells with memory-like properties were generated during chronic infection. After transfer into naive mice, these cells robustly proliferated and controlled a viral infection. The reexpanded T cell populations continued to have the exhausted phenotype they acquired during the chronic infection. Thus, the cells underwent a form of differentiation that was stably transmitted to daughter cells. We therefore propose that during persistent infection, effector T cells stably differentiate into a state that is optimized to limit viral replication without causing overwhelming immunological pathology.
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The characterisation of lymphocytes from liver biopsies indicates that 'activated' T lymphocytes are present in the liver in alcohol induced hepatitis, chronic active hepatitis (HBS+ve and -ve), and in primary biliary cirrhosis but not in inactive cirrhosis, chronic persistent hepatitis, extrahepatic and drug induced cholestasis. A greater percentage of lymphocytes bear Fc-receptors in chronic active hepatitis than in alcohol induced hepatitis or cholestatic liver disease. The concentration of 'activated' T cells in the peripheral blood in all groups studied was within the normal range, suggesting that the 'activated' T cells found in the liver were reacting to either native or foreign antigens within the liver. The data on Fc-receptor bearing cells are consistent with the involvement of antibody assisted K cell mediated cytotoxicity in chronic active hepatitis.
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Oxalic and oxamic acids are the ultimate and more persistent by-products of the degradation of N-aromatics by electrochemical advanced oxidation processes (EAOPs). In this paper, the kinetics and oxidative paths of these acids have been studied for several EAOPs using a boron-doped diamond (BDD) anode and a stainless steel or an air-diffusion cathode. Anodic oxidation (AO-BDD) in the presence of Fe2+ (AO-BDD-Fe2+) and under UVA irradiation (AO-BDD-Fe2+-UVA), along with electro-Fenton (EF-BDD), was tested. The oxidation of both acids and their iron complexes on BDD was clarified by cyclic voltammetry. AO-BDD allowed the overall mineralization of oxalic acid, but oxamic acid was removed much more slowly. Each acid underwent a similar decay in AO-BDD-Fe2+ and EFBDD, as expected if its iron complexes were not attacked by hydroxyl radicals in the bulk. The faster and total mineralization of both acids was achieved in AO-BDD-Fe2+-UVA due to the high photoactivity of their Fe(III) complexes that were continuously regenerated by oxidation of their Fe(II) complexes. Oxamic acid always released a larger proportion of NH4 + than NO3- ion, as well as volatile NOx species. Both acids were independently oxidized at the anode in AO-BDD, but in AO-BDD-Fe2+-UVA oxamic acid was more slowlydegraded as its content decreased, without significant effect on oxalic acid decay. The increase in current density enhanced the oxidation power of the latter method, with loss of efficiency. High Fe2+ contents inhibited the oxidation of Fe(II) complexes by the competitive oxidation of Fe2+ to Fe3+. Low current densities and Fe2+ contents are preferable to remove more efficiently these acids by the most potent AO-BDD-Fe2+-UVA method.
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High mortality in newborn babies with congenital diaphragmatic hernia (CDH) is principally due to persistent pulmonary hypertension. ATP-dependent potassium (K(ATP)) channels might modulate pulmonary vascular tone. We have assessed the effects of Pinacidil, a K(ATP) channel opener, and glibenclamide (GLI), a K(ATP) channel blocker, in near full-term lambs with and without CDH. In vivo, pulmonary hemodynamics were assessed by means of pressure and blood flow catheters. In vitro, we used isolated pulmonary vessels and immunohistochemistry to detect the presence of K(ATP) channels in pulmonary tissue. In vivo, pinacidil (2 mg) significantly reduced pulmonary vascular resistance (PVR) in both controls and CDH animals. GLI (30 mg) significantly increased pulmonary arterial pressure (PAP) and PVR in control animals only. In vitro, pinacidil (10 microM) relaxed, precontracted arteries from lambs with and without CDH. GLI (10(-5) microM) did not raise the basal tone of vessels. We conclude that activation of K(ATP) channels could be of interest to reduce pulmonary vascular tone in fetal lambs with CDH, a condition often associated with persistent pulmonary hypertension of the newborn.
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PURPOSE: We evaluate the functional and anatomic outcome after intravitreal ranibizumab treatment in patients with choroidal neovascularization (CNV) related to chronic central serous chorioretinopathy (CSC). METHODS: This is a small case series of 5 eyes with CNV associated with chronic CSC treated with intravitreal injection of 0.5 mg ranibizumab in the Jules Gonin University Eye Hospital from July 2007 to July 2009. Baseline and monthly follow-up visits included best-corrected visual acuity (BCVA), fundus examination, and optical coherence tomography (OCT). Fluorescein and indocyanine green angiography (ICG) were performed at baseline and repeated at least every 6 months. RESULTS: We studied 5 eyes of 4 patients with a mean age of 66 years. Mean follow-up was 21 months (SD 1.9). The mean number of intravitreal injections administered for each patient was 10 (SD 4.6). The mean initial BCVA was 0.23 (decimal equivalent) (logMAR 0.64, SD 0.13). At the last follow-up, mean BCVA was 0.44 decimal equivalent (logMAR 0.36, SD 0.31). Mean central macular thickness (CMT) measured with OCT was 330 microm (SD 43) at baseline and decreased at the final follow-up to 243 microm (SD 44 ). Persistent intraretinal or subretinal fluid on OCT and/or multifocal areas of increased choroidal permeability on ICG angiographies were present in all patients at the last follow-up visit. CONCLUSIONS: Intravitreal ranibizumab appeared to be an effective treatment of CNV related to chronic CSC. However, residual intraretinal or subretinal fluid and increased choroidal permeability persisted. Prospective controlled studies are warranted to evaluate the long-term safety and efficacy of intravitreal ranibizumab.
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Seit 1988 finden in regelmässigen Abständen gesamtschweizerische Gemeindeschreiberbefragungen statt. In dieser Studie werden die Ergebnisse der Erhebung 2005 vorgestellt. Im Zentrum stehen dabei die Ausgestaltung der politischen Systeme der Gemeinden und verschiedene Aspekte der lokalen Politik. Es zeigt sich, dass die grossen Unterschiede hinsichtlich der politischen Organisation der Gemeinden auch in Zukunft kaum kleiner werden dürften. Es lässt sich keine, alle anderen überragende Organisationsform ausmachen. Vor allem in den kleineren Gemeinden ist die Bedeutung der politischen Parteien in den letzten Jahren stark zurückgegangen. Dies könnte dazu führen, dass ein neuer Pragmatismus Einzug in die Lokalpolitik nimmt. Depuis 1988 et par la suite à des intervalles réguliers, des enquêtes auprès des secrétaires municipaux de la Suisse ont eu lieu. Cette étude présente les résultats de l'enquête 2005 et se focalise sur l'organisation politico-administrative des communes ainsi que sur différents aspects de la politique locale. En ce qui concerne l'organisation des communes, nous pouvons constater que de grandes différences entre les municipalités persistent : aucune forme organisationnelle ne prime sur les autres. Par rapport aux partis politiques, leur importance a fortement reculé surtout dans les petites communes. Un nouveau pragmatisme pourrait ainsi marquer la politique locale à venir.