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11.
The aim of this study was to investigate the relationship between mucosal gizzard lesions and caecal Clostridium perfringens counts. Gross pathological changes in the gizzard and small intestine, and caecal C. perfringens counts from 1217 meat-type chickens were recorded during the course of six experiments and were statistically analysed. C. perfringens counts increased significantly (P < 0.001) with the severity of mucosal gizzard lesions. Mucosal gizzard lesions were more prevalent than necrotic enteritis. Correcting for the pen and necrotic enteritis within experiment, mucosal gizzard lesions explained 31.8% of the variation in C. perfringens counts. Mucosal gizzard lesions and age together explained 59.1% of the variation in C. perfringens counts. The mean ages of birds with moderate and severe mucosal gizzard lesions were 1.7 and 0.8 days lower than the mean age of birds with necrotic enteritis, respectively. The association between mucosal gizzard lesions and high C. perfringens counts might be of importance when attempting to improve production efficiency, health and the welfare of the chickens. 相似文献
12.
Margarita Gallego Emilio del Cacho Agustin Zapata Jose Antonio Bascuas 《Anatomical record (Hoboken, N.J. : 2007)》1995,242(2):220-224
Background: There is a need to identify the follicular dendritic cells (FDC) of the chicken spleen at the ultrastructural level during a secondary immune response. Methods: The cells were identified after intravenous priming BSA and boosting with biotinylated BSA conjugated to colloidal gold particles. Monoclonal antibodies raised specifically either to chicken IgG or IgM were used to characterize these immune complex-trapping cells. Results: The FDC had an irregular morphology which varied through time, supporting the existence of two types of FDC in the chicken spleen, one showing filiform cell processes, the other provided with beaded dendrites. When the filiform dendrites were observed, the FDC bound the antigen on their surfaces. These dendrites showed an intrincate convoluted configuration, forming tightly wrapped networks near the cell body. The networks had the same features as those described in mammals as antigen retaining reticulum (ARR). In chickens, the ARR, which represents sites of antigen localization on FDC, reached maximum development on day 5 after the second injection of BSA and had disappeared by day 8. At this time FDC had beaded dendrites. Conclusions: Antigen is retained on FDC in the chicken spleen for long periods of time. © 1995 Wiley-Liss, Inc. 相似文献
13.
Nine depressive patients were examined before bilateral electroconvulsive therapy (ECT), immediately after ECT, and 2 days later with saccadic, pursuit tracking, and Hallpike caloric vestibular tests. Before ECT, all tests showed normal results. Immediately after ECT, the saccadic test displayed dysmetria of the fast eye movements in six of nine patients. The pursuit tracking test showed decreased gain of the slow eye movements with compensatory saccades in seven of nine patients. These findings were for both directions in the horizontal plane. In the caloric vestibular test, the changes were not significant. Two days after ECT, the eye coordination and vestibular testing showed normal function. We conclude that the eye coordination and vestibular function disturbances induced by ECT are transient. 相似文献
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Beu P. Oropeza Carlos Serna III Michael E. Furth Luis H. Solis Cesar E. Gonzalez Valeria Altamirano Daisy C. Alvarado Jesus A. Castor Jesus A. Cedeno Dante Chaparro Vega Octavio Cordova Isaac G. Deaguero Erwin I. Delgado Mario F. Garcia Duarte Mirsa Gonzalez Favela Alba J. Leyva Marquez Emilio S. Loera Gisela Lopez Fernanda Lugo Tania G. Miramontes Erik Munoz Paola A. Rodriguez Leila M. Subia Arahim A. Zuniga Herrera Thomas Boland 《Materials》2022,15(13)
The rapidly growing field of tissue engineering hopes to soon address the shortage of transplantable tissues, allowing for precise control and fabrication that could be made for each specific patient. The protocols currently in place to print large-scale tissues have yet to address the main challenge of nutritional deficiencies in the central areas of the engineered tissue, causing necrosis deep within and rendering it ineffective. Bioprinted microvasculature has been proposed to encourage angiogenesis and facilitate the mobility of oxygen and nutrients throughout the engineered tissue. An implant made via an inkjet printing process containing human microvascular endothelial cells was placed in both B17-SCID and NSG-SGM3 animal models to determine the rate of angiogenesis and degree of cell survival. The implantable tissues were made using a combination of alginate and gelatin type B; all implants were printed via previously published procedures using a modified HP inkjet printer. Histopathological results show a dramatic increase in the average microvasculature formation for mice that received the printed constructs within the implant area when compared to the manual and control implants, indicating inkjet bioprinting technology can be effectively used for vascularization of engineered tissues. 相似文献
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Anna Suchankova Margarita Stampelou Klontiana Koutsouki Athanasios Pousias Lakshiv Dhingra Kerry Barkan Nicole Pouli Panagiotis Marakos Roxane Tenta Antonios Kolocouris Nikolaos Lougiakis Graham Ladds 《ACS medicinal chemistry letters》2022,13(6):923
Here we describe the design and synthesis of pyrazolo[3,4-d]pyridazines as adenosine receptor (AR) ligands. We demonstrate that the introduction of a 3-phenyl group, together with a 7-benzylamino and 1-methyl group at the pyrazolopyridazine scaffold, generated the antagonist compound 10b, which displayed 21 nM affinity and a residence time of ∼60 min, for the human A1R, 55 nM affinity and a residence time of ∼73 min, for the human A3R and 1.7 μΜ affinity for the human A2BR while not being toxic. Strikingly, the 2-methyl analog of 10b, 15b, had no significant affinity. Docking calculations and molecular dynamics simulations of the ligands inside the orthosteric binding area suggested that the 2-methyl group in 15b hinders the formation of hydrogen bonding interactions with N6.55 which are considered critical for the stabilization inside the orthosteric binding cavity. We, therefore, demonstrate that 10a is a novel scaffold for the development of high affinity AR ligands. From the mutagenesis experiments the biggest effect was observed for the Y2717.46A mutation which caused an ∼10-fold reduction in the binding affinity of 10b. 相似文献
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Simona Sacco Faisal Mohammad Amin Messoud Ashina Lars Bendtsen Christina I. Deligianni Raquel Gil-Gouveia Zaza Katsarava Antoinette MaassenVanDenBrink Paolo Martelletti Dimos-Dimitrios Mitsikostas Raffaele Ornello Uwe Reuter Margarita Sanchez-del-Rio Alexandra J. Sinclair Gisela Terwindt Derya Uluduz Jan Versijpt Christian Lampl 《The journal of headache and pain》2022,23(1)
BackgroundA previous European Headache Federation (EHF) guideline addressed the use of monoclonal antibodies targeting the calcitonin gene-related peptide (CGRP) pathway to prevent migraine. Since then, randomized controlled trials (RCTs) and real-world evidence have expanded the evidence and knowledge for those treatments. Therefore, the EHF panel decided to provide an updated guideline on the use of those treatments.MethodsThe guideline was developed following the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) approach. The working group identified relevant questions, performed a systematic review and an analysis of the literature, assessed the quality of the available evidence, and wrote recommendations. Where the GRADE approach was not applicable, expert opinion was provided.ResultsWe found moderate to high quality of evidence to recommend eptinezumab, erenumab, fremanezumab, and galcanezumab in individuals with episodic and chronic migraine. For several important clinical questions, we found not enough evidence to provide evidence-based recommendations and guidance relied on experts’ opinion. Nevertheless, we provided updated suggestions regarding the long-term management of those treatments and their place with respect to the other migraine preventatives.ConclusionMonoclonal antibodies targeting the CGRP pathway are recommended for migraine prevention as they are effective and safe also in the long-term.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10194-022-01431-x. 相似文献
20.
M. Jesús Cerecedo Pérez Margarita Tovar Bobo Aurora Rozadilla Arias 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2013,45(10):536-540
The power of medicine has lately enhanced the idea of medicalizing any aspects of life that can be perceived as medical problems. Medicine sometimes creates false needs and there is nowadays an increasing number of situations are medicalized with the pretext of treating fake diseases such as spring fatigue, shyness o natural biological processes like menopause.Despite the better life conditions, we now attend more people that complain about discomfort that may have more to do with «feeling sick» than with authentic disease. There is an endless list: sadness, hyperactive children, anorexia, bulimia, vigorexia or problematic teenagers, amongst others. In this article we revise some interventions that, contribute to promote these situations also from the own doctor's office. Everyday adversity acquires today the status of disease, hence the remarkable increase in these consultations in the diverse sanitary services. 相似文献