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1.
Maria Guiomar A Bahia Vicente Tadeu Lopes Buono 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,100(2):249-255
OBJECTIVE: The changes in fatigue resistance of nickel-titanium rotary ProFile instruments after clinical use for shaping 10 curved molar root canals were evaluated in this study. STUDY DESIGN: Twenty-five sets of files #20, #25, and #30 and tapers .04 and .06 were divided into 2 groups, one with 10 sets of new files that were tested in a fatigue test bench device as a control. The other, experimental group, with 15 sets of clinically used files, was tested in the same device. The Student t test was employed to compare mean values of the measured parameters. RESULTS: A statistically significant decrease in the number of cycles to failure was determined for the clinically used files, as compared with the new ones. The fracture point was the same for all files tested. CONCLUSIONS: The clinical use of ProFile instruments for shaping curved canals reduces their fatigue resistance. 相似文献
2.
Carlos Solano Lourdes Vázquez Estela Giménez Rafael de la Cámara Eliseo Albert Montserrat Rovira Ildefonso Espigado Carmen M. Calvo Javier López-Jiménez María Suárez-Lledó Anabella Chinea Albert Esquirol Ariadna Pérez Aránzazu Bermúdez Raquel Saldaña Inmaculada Heras Ana J. González-Huerta Tamara Torrado Guiomar Bautista Montserrat Batlle Santiago Jiménez Carlos Vallejo Pere Barba María Á. Cuesta José L. Piñana David Navarro 《American journal of transplantation》2021,21(1):258-271
The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research. 相似文献
3.
As far as we know, after adult enzyme-digested pancreatic fragment autotransplantation, the fate of the inoculated pancreatic tissue has never been reported and the hypothetic engrafted islet mass growth by mitotic division or by a true islet neogenesis from ductular precursor cells has never been demonstrated. In dogs with total or near-total (90%) pancreatectomy that preserves the duodenum and the common bile duct, morphologic study of the pancreatic tissue inoculated into the spleen has demonstrated an exuberant ductular-acinar-islet regenerative process, with progressive cystic degeneration of the newly formed ductular-acinar structures occurring simultaneously with the selective survival and growing predominance of extraductal tissue scattered as distinct islets, clusters of islet cells, or single islet cells. In addition to the B, A2, and D cell types of the normal adult dog islet, we have also seen a peculiar ultrastructural pleomorphism of the insular B cells, frequently combined with their ductular or glandular arrangement in maturing islets. Rare or never before reported islet cell types in the adult dog's islets (G cells, mixed endocrine cells of the A2-D, D-B, and A2-B types, and mixed acinar-islet cells of the D-acinar type) were also putatively identified. Using light microscopy we have identified many mitotic figures on ductular and centroacinar cells in ductules and ductular-acinar structures. Moreover, we have ultrastructurally characterized a pluriendocrine nesidioblastic process identified in the most common islet cell types (B, A2, D) and in G cells and mixed acinar islet cells of the B-ac, A2-ac, D-ac, F-ac, and G-ac types as well as intermediary or transitional cells of incipient ductular-acinar, ductular-islet, and ductular-acinar-islet differentiation. The characteristics of the extraductal islet tissue and the exuberant nesidioblastic process have demonstrated neogenesis of islets and islet cells from precursor ductular cells at several points after the autotransplant, and we suggest that this mechanism may be of fundamental importance for the engrafted islet mass growth—keeping in mind the age of the pancreatic tissue donors and the life-span of the juvenile diabetic recipient receiving the transplant. This evolution has taken place simultaneously with the progressive rarefaction of the regenerated ductular-acinar structures definitively deprived of an intestinal drainage route by virtue of their heterotopic location.
Resumen Hasta donde sabemos, después del autotrasplante de fragmentos pancreáticos enzimáticamente digeridos, no se ha reportado la evolución final del tejido pancreático inoculado; y el crecimiento de la hipotética masa del tejido insular trasplantado, por división mitótica a por verdadera neogénesis de islotes a partir de células ductales precursoras, nunca ha sido demostrado.En el perro sometido a pancreatectomía total o casi total (90%) con preservación del duodeno y del colédoco, el estudio morfológico del tejido pancreático inoculado en el bazo ha demostrado un exuberante proceso regenerativo de células dactulares-acinares-insulares-, con progresiva degeneración quística de las neoformadas estructuras ductulares-acinares simultánea con la sobrevida selectiva y el crecimiento predominante del tejido insular a partir de ductos, y de células insulares aisladas o en grupos. Además de los tipos B, A2 y D de las células insulares del perro, también hemos podido identificar un peculiar pleomorfismo ultraestructural de las células insulares B, con frecuencia combinado con su ordenación ductular o glandular en los islotes en vía de maduración. También fueron putativamente identificados tipos celulares muy raros o nunca reportados en los islotes caninos (células G, células endocrinas mixtas de los tipos A2/D, D/B, Y A2/B, y células mixtas acinares e insulares del tipo D-acinar). En las estructuras ductulares y ductular-acinares hemos podido reconocer muchas figuras mitóticas en células ductulares y centroacinares mediante microscopia de luz y un proceso pluriendocrino nesidio-blástico con la identificación netraestructural de los tipos más comunes de células insulares (B, A2, D), pero también células G y células mixtas acinar-insulares de los tipos B-ac, A2-ac, D-ac, F-ac y G-ac, así como células intermedias o transicionales de la incipiente diferenciación ductular-acinar, ductular-insular, y ductular-acinar-insular. Las caracteristicas del tejido insular originado en ductos y el exuberante proceso nesidioblástico han demostrado la neogénesis de células insulares y de islotes a partir de células precursoras en diferentes períodos después del autotrasplante; nosotros sugerimos que este mecanismo puede ser de importancia fundamental para el crecimiento de la masa insular trasplantada, teniendo en cuenta la edad de los donantes de tejido pancreático y la duración de la vida de los recipientes diabéticos y juveniles. Esta evolución ha cursado con una progresiva rarefacción de las estructuras ductulares-acinares, definitivamente desprovista de una vía de drenaje intestinal debido a su ubicación heterotópica.相似文献
4.
Filipa Alves da Costa Jos Pedro Guerreiro Magda Nunes de Melo Ana da Costa Miranda Ana Paula Martins Jos Garo Brenda Madureira 《The International journal of pharmacy practice》2005,13(3):205-211
Objective Poor compliance to antihypertensive medications has been identified as a primary cause of uncontrolled blood pressure (BP), with consequent increases in hypertension‐related morbidity and mortality. Therefore, any measure known to improve compliance should be encouraged. This study assessed the impact of reminder cards on compliance to antihypertensive therapy. Method A field trial was undertaken in pharmacies located in the districts of Lisbon and Porto. Eligible participants comprised those aged 30–74 years, prescribed an angiotensin‐converting enzyme inhibitor (ACEI) in monotherapy, and taken on a once‐daily regimen. Patients were allocated to control group (CG) or intervention group (IG), the latter being provided with a reminder card, an alarm‐type device due to remind the patient of the time to take his medication. Patients were monitored monthly during 3 months for compliance and blood pressure control. Key findings Seventy‐one patients participated in the study (intervention: 35; control group: 36). Compliance was similar between the groups in the first 2 months of follow‐up (97.1% IG vs 94.9% CG at first follow‐up and 97.5% IG vs 94.2% CG at second follow‐up) and higher in the intervention group at the end of the study (97.3% IG vs 87.3% CG; P = 0.011). There were no mean blood pressure differences between compliant and non‐compliant subjects at the end of the study (P value for differences in systolic BP (Psyst) = 0.580; and P value for differences in diastolic BP (Pdlast) = 0.175). Conclusion This small‐scale study indicates a possible positive impact on patients' compliance resulting from the use of reminder cards. However, this needs confirming in larger scale studies with longer monitoring periods. 相似文献
5.
Indoor fungal diversity in primary schools may differently influence allergic sensitization and asthma in children
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6.
Crutel Véronique Lambert Estelle Penelaud Pierre-François Albarrán Severo Cristina Fuentes Joaquin Rosier Antoine Hervás Amaia Marret Stéphane Oliveira Guiomar Parellada Mara Kyaga Simon Gouttefangeas Sylvie Bertrand Marianne Ravel Denis Falissard Bruno 《Journal of autism and developmental disorders》2021,51(8):2973-2973
Journal of Autism and Developmental Disorders - The author of the article would like to add a video abstract as a supplementary material for a published article. The supplementary file is published... 相似文献
7.
The acute toxicity of mercury (Hg) to B cells was studied in the peritoneal cavity of BALB/c mice, a coelomic space where both B-1 and B-2 subsets of B lymphocytes are present. Up to 24 hr after a single in situ Hg injection, the peritoneal cavity became virtually devoid of lymphocytes, particularly of the B-1 subset. Lymphocyte depletion was more severe for B than T cells. This depletion was associated with partial lymphocyte activation (CD69+) at 6 hr of treatment and it was due to apoptosis rather than to necrosis. Partial recovery of both B and T cells was observed in the peritoneal cavity 48 hr after the Hg injection. The phenomenon was followed by a second decrease in peritoneal lymphocytes 72 hr after Hg. Neutrophils that entered the peritoneal cavity because of the Hg injection were resistant to apoptosis. No significant changes in lymphocyte number or subpopulation were found in the spleen and thymus of the mice up to 72 hr after the Hg treatment. We concluded that B lymphocytes were severely affected by the toxic effects of Hg. Our data suggest that Hg-induced unbalance in the repertoire of B cells, of the B-1 subset in particular, may result later in the secretion of the high titres of pathogenic autoantibodies that are found in the Hg-induced lupus disorder of BALB/c mice. 相似文献
8.
Andreas Lazaros Chryssafidis Germán Cantón Francesca Chianini Elisabeth A. Innes Ed Hoffmann Madureira Solange Maria Gennari 《Parasitology research》2014,113(4):1521-1528
Neospora caninum is a protozoan parasite known as an important cause of bovine abortion worldwide. Little is currently known about how different strains of N. caninum vary in their pathogenicity. In this study, we compared a Brazilian strain, Nc-Bahia, with the first isolate of this coccidian, Nc-1. Eight cows and seven buffaloes were submitted to fixed-time artificial insemination protocols for a better control of pregnancy. Group 1 was inoculated with Nc-Bahia (n?=?8; five cows and three buffaloes), and Group 2 was inoculated with Nc-1 (n?=?5; two cows and three buffaloes). One nonpregnant female of each species was left uninfected as sentinel controls for potential environmental infection. All inoculated animals received 5?×?108 tachyzoites of N. caninum, by intravenous route, on the 70th day of gestation. Uninfected animals remained seronegative throughout the experiment, indicating no exogenous infection, whereas all inoculated animals became seropositive to N. caninum. In Group 1, abortion was found in only one cow on 42 days postinfection (dpi; frequency of abortion?=?12.5 %), whilst all animals from Group 2 aborted on 35 dpi (frequency of abortion?=?100 %). Parasite DNA was detected by seminested PCR in maternal, foetal and placental tissues, confirming vertical transmission in Groups 1 and 2, although histological lesions had different frequencies and degrees of severity between the groups. There was evidence of lower pathogenicity of Nc-Bahia compared to Nc-1 when used in experimental infection, as it caused fewer abortions, as well as less frequent and milder histological lesions. This was the first time Nc-Bahia has been used for experimental infection. 相似文献
9.
Guiomar Niso Ricardo Bruña Ernesto Pereda Ricardo Gutiérrez Ricardo Bajo Fernando Maestú Francisco del-Pozo 《Neuroinformatics》2013,11(4):405-434
The analysis of the interdependence between time series has become an important field of research in the last years, mainly as a result of advances in the characterization of dynamical systems from the signals they produce, the introduction of concepts such as generalized and phase synchronization and the application of information theory to time series analysis. In neurophysiology, different analytical tools stemming from these concepts have added to the ‘traditional’ set of linear methods, which includes the cross-correlation and the coherency function in the time and frequency domain, respectively, or more elaborated tools such as Granger Causality. This increase in the number of approaches to tackle the existence of functional (FC) or effective connectivity (EC) between two (or among many) neural networks, along with the mathematical complexity of the corresponding time series analysis tools, makes it desirable to arrange them into a unified-easy-to-use software package. The goal is to allow neuroscientists, neurophysiologists and researchers from related fields to easily access and make use of these analysis methods from a single integrated toolbox. Here we present HERMES (http://hermes.ctb.upm.es), a toolbox for the Matlab® environment (The Mathworks, Inc), which is designed to study functional and effective brain connectivity from neurophysiological data such as multivariate EEG and/or MEG records. It includes also visualization tools and statistical methods to address the problem of multiple comparisons. We believe that this toolbox will be very helpful to all the researchers working in the emerging field of brain connectivity analysis. 相似文献
10.
Daniela Teixeira Joaquim Soares de Almeida Bruna Visniauskas Guiomar Nascimento Gomes Aparecida Emiko Hirata Valquiria Bueno 《Clinics (S?o Paulo, Brazil)》2013,68(6):858-864