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排序方式: 共有2731条查询结果,搜索用时 15 毫秒
101.
Giorgio SilvaSantana Juliet Cunha Bax Dbora Cristina Silva Fernandes Daniela Tendler Leibel Bacellar Cleber Hooper Alexandre Alves Souza Oliveira Dias Cristina Barbosa Silva Aline Moreira de Souza Simone Ramos Ricardo Alexandre Santos Thainara Ramos Pinto Mariana Antunes Ramo Ana Luíza MattosGuaraldi 《动物模型与实验医学(英文)》2020,3(4):304
BackgroundAnimal models are widely used in scientific research in order to obtain information from a whole organism under a specific set of experimental conditions. Various lineages of mice have been used to investigate diseases and new therapeutic strategies, and, consequently, hematological and biochemical tests in these laboratory animals are essential to validate scientific studies. Our study seeks to establish reference values for hematological and biochemical parameters of four lineages of mice.MethodsWe evaluated the hematological and biochemical profiles of 20 males and 20 females from the lineages Swiss (heterogeneous), BALB/c and C57BL/6 (isogenic), and B6D2F1 (hybrid), totaling 160 mice. Analysis were standardized using the systems pocH‐100iV Diff™ for 19 hematological parameters and VITROS® 350 for 12 biochemical parameters.ResultsResults are shown as means and standard deviation, grouped by lineage and genre. Comparing the values obtained in this study with the values from previous studies, some variations were detected, which could be explained by differences in methodologies or individual variability.ConclusionThus our study shows that knowledge and disclosure of the values of physiological parameters of laboratory animals is necessary, and emphasises the importance of considering variations influenced by gender, lineage and genotype in the choice of the best experimental model. 相似文献
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Erica S. Shenoy Farzad Noubary JiYeon Kim Eric S. Rosenberg Jessica A. Cotter Hang Lee Rochelle P. Walensky David C. Hooper 《Journal of clinical microbiology》2014,52(4):1235-1237
The effect of concurrent administration of antibiotics on the detection of methicillin-resistant Staphylococcus aureus (MRSA) remains unresolved. Here, we assessed the concordance of paired nasal swabs processed using commercial PCR and culture and found high concordance in both the absence and presence of antibiotics with activity against MRSA (93.7% [95% confidence interval [CI], 88.1%, 96.8%] and 90.9% [95% CI, 84.8%, 94.7%], respectively), although PCR was more likely to be positive in the presence of antibiotics. (This study has been registered at ClinicalTrials.gov under registration no. .) NCT01234831相似文献
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Holly McKnight W. Patrick Kelsey Deborah A. Hooper Thomas C. Hart Angelo Mariotti 《Journal of periodontology》2014,85(6):810-818
Background: Although human gingival fibroblasts (hGFs) and human periodontal ligament fibroblasts (hPDLFs) exhibit numerous phenotypic similarities, it has been suggested that the secretory and behavioral differences, which exist between these cell types, are a result of the membrane protein composition of these cells. Methods: Four matched pairs of hGFs and hPDLFs were cultured. Before confluence, membrane‐bound and ‐associated proteins from cells of the fourth passage were extracted. The processed protein samples were evaluated using capillary‐liquid chromatography‐nanospray tandem mass spectrometry. Global protein identification was performed on an orbitrap mass spectrometer equipped with a microspray source operated in positive ion mode. Proteome software was used to validate protein identifications derived from tandem mass spectrometry sequencing results. Results: Four hundred fifty proteins were common to both hGFs and hPDLFs. Of the proteins identified, 214 were known membrane‐bound or ‐associated proteins, and 165 proteins were known nuclear‐associated proteins. Twenty‐seven proteins, identified from the 450 proteins, common to both hGFs and hPDLFs, were detected in statistically significant greater quantities in either hGFs or hPDLFs. More specifically, 13 proteins were detected in significantly greater quantities in hGFs, whereas 14 proteins were detected in significantly greater quantities in hPDLFs. Conclusions: Distinct differences in the cellular protein catalog may reflect the dynamic role and high energy requirements of hGFs in extracellular matrix remodeling and response to inflammatory challenge as well as the role of hPDLFs in monitoring mechanical stress and maintaining tissue homeostasis during regeneration and remineralization. 相似文献
104.
Tripathi Sushil K. Kean Rhonda Bongiorno Emily Hooper Douglas C. Jin Yuan-Yuan Wickstrom Eric McCue Peter A. Thakur Mathew L. 《Molecular imaging and biology》2020,22(2):293-302
Molecular Imaging and Biology - Scintigraphic imaging of malignant glioblastoma (MG) continues to be challenging. We hypothesized that VPAC1 cell surface receptors can be targeted for positron... 相似文献
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B-cell growth factor receptor expression and B-cell growth factor response of leukemic B cell precursors and B lineage lymphoid progenitor cells 总被引:8,自引:1,他引:8
Uckun FM; Fauci AS; Heerema NA; Song CW; Mehta SR; Gajl-Peczalska K; Chandan M; Ambrus JL 《Blood》1987,70(4):1020-1034
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL. 相似文献
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Characterization of a novel subtype of hippocampal interneurons that express corticotropin‐releasing hormone
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A subset of corticotropin‐releasing hormone (CRH) neurons was previously identified in the hippocampus with unknown function. Here we demonstrate that hippocampal CRH neurons represent a novel subtype of interneurons in the hippocampus, exhibiting unique morphology, electrophysiological properties, molecular markers, and connectivity. This subset of hippocampal CRH neurons in the mouse reside in the CA1 pyramidal cell layer and tract tracing studies using AAV‐Flex‐ChR2‐tdTomato reveal dense back‐projections of these neurons onto principal neurons in the CA3 region of the hippocampus. These hippocampal CRH neurons express both GABA and GAD67 and using in vitro optogenetic techniques, we demonstrate that these neurons make functional connections and release GABA onto CA3 principal neurons. The location, morphology, and importantly the functional connectivity of these neurons demonstrate that hippocampal CRH neurons represent a unique subtype of hippocampal interneurons. The connectivity of these neurons has significant implications for hippocampal function. © 2015 Wiley Periodicals, Inc. 相似文献