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排序方式: 共有560条查询结果,搜索用时 15 毫秒
1.
Sheela R Geraghty Barbara S Davidson Barbara B Warner Amy L Sapsford Jeanne L Ballard Betsy A List Rachel Akers Ardythe L Morrow 《Journal of human lactation》2005,21(1):59-66
Although there are well-established clinical human milk banks in the United States, there are no milk banks specifically intended to foster research on human milk. The authors' goal was to establish a milk bank with a core data set to support exploratory and hypothesis-driven studies on human milk. Donations to the Cincinnati Children's Research Human Milk Bank are accepted within the context of ongoing, hypothesis-driven research or on an ad hoc basis. Donors must give informed consent, and scientists wishing to use the samples must have Institutional review board approval for their use. Development of more research human milk banks can potentially provide resources for multidisciplinary collaboration and advance the study of human milk and lactation. 相似文献
2.
Eugene Chung Sheela B. Amrute Kristina Abel Gunjan Gupta Yichuan Wang Christopher J. Miller Patricia Fitzgerald-Bocarsly 《Clinical and Vaccine Immunology : CVI》2005,12(3):426-435
Plasmacytoid dendritic cells (PDC) are potent producers of alpha interferon (IFN-α) in response to enveloped viruses and provide a critical link between the innate and adaptive immune responses. Although the loss of peripheral blood PDC function and numbers has been linked to human immunodeficiency virus (HIV) progression in humans, a suitable animal model is needed to study the effects of immunodeficiency virus infection on PDC function. The rhesus macaque SIV model closely mimics human HIV infection, and recent studies have identified macaque PDC, potentially making the macaque a good model to study PDC regulation. In this study, we demonstrate that peripheral blood PDC from healthy macaques are both phenotypically and functionally similar to human PDC and that reagents used for human studies can be used to study macaque PDC. Both human and macaque PBMC expressed IFN-α in response to herpes simplex virus (HSV), the prototypical activator of PDC, as measured by using an IFN bioassay and IFN-α-specific enzyme-linked immunospot assays. Similar to human PDC, macaque PDC were identified by using flow cytometry as CD123+ HLA-DR+ lineage− cells. In addition, like human PDC, macaque PDC expressed intracellular IFN-α, tumor necrosis factor alpha, macrophage inflammatory protein 1β/CCL4, and IFN-inducible protein 10/CXCL10 upon stimulation with HSV, all as determined by intracellular flow cytometry. We found that IFN regulatory factor 7, which is required for the expression of IFN-α genes, was, similar to human PDC, expressed at high levels in macaque PDC compared to monocytes and CD8+ T cells. These findings establish the phenotypic and functional similarity of human and macaque PDC and confirm the utility of tools developed for studying human PDC in this animal model. 相似文献
3.
Sharma Sheela Wyatt Gail P. Elmore Eugene L. Steele Vernon E. 《Methods in Cell Science》1997,19(1):9-12
An in vitro model for screening potential chemopreventive agents using inhibition of anchorage-independent growth of a human lung tumor cell line, A427, is described. A427 cells were selected for the model development, as they are known to be tumorigenic in animals, can grow in soft agarose, and their growth can be inhibited by a well-known chemopreventive agent, 13-cis-retinoic acid. Cells are plated on agarose, allowed to develop colonies for 28 days, the stained colonies are enumerated, and the inhibition of spontaneous colony formation measured. A cytotoxicity test is used concurrently with anchorage independent assay for measuring the relative survival of cells to ensure that any observed inhibition of anchorage independent growth is due to the biological activity of the chemopreventive agents, as it uses human cells as substrates rendering the efficacy data feasible for direct extrapolation to humans. 相似文献
4.
Differential regulation of IL-13 and IL-4 production by human CD8+ and CD4+ Th0, Th1 and Th2 T cell clones and EBV-transformed B cells 总被引:3,自引:0,他引:3
Malefyt Rene de Waal; Abrams John S.; Zurawski Sandra M.; Lecron Jean-Claude; Mohan-Peterson Sheela; Sanjanwala Bharati; Bennett Bruce; Silver Jon; de Vries Jan E.; Yssel Hans 《International immunology》1995,7(9):1405-1416
In the present study, the requirements and characteristics forthe production of IL-13 by human T cells, T cell clones andB cells were determined and compared with those of IL-4. IL-13was produced by human CD4+ and CD8+ T lymphocyte subsets isolatedfrom peripheral blood mononuclear cells and by CD4+ and CD8+T cell clones. CD4+ T cell clones belonging to Th0, Th1-likeand Th2-like subsets produced IL-13 following antigen-specificor polyclonal activation. In addition, EBV-transformed B celllines expressed IL-13 mRNA and produced small amounts of IL-13protein. Expression of IL-13 mRNA and production of IL-13 proteinby peripheral blood T cells and T cell clones was induced rapidlyand was relatively long lasting, whereas IL-4 production bythese cells was transient In addition, IL-13 mRNA expressionwas induced by modes of activation that failed to induce IL-4mRNA expression. IL-13 shares many biological activities withIL-4 which Is compatible with the notion that the IL-13 andIL-4 receptors share a common component required for signaltransduction. However, IL-13 lacks the T cell-activating propertiesof IL-4. Here we have shown that this is related to the factthat T cells fall to bind radiolabeled IL-13 and do not expressthe IL-13-speclflc receptor component Taken together, theseresults indicate that the differences In expression and biologicalactivities of IL-4 and IL-13 on T cells may have consequencesfor the relative roles of these cytokines In the immune response. 相似文献
5.
Journal of Digital Imaging - In the human body, cancer is caused by aberrant cell proliferation. Brain tumors are created when cells in the human brain proliferate out of control. Brain tumors... 相似文献
6.
Ananthan S Sheela M Subramanian MA Sankaranarayanan VS 《Indian journal of pediatrics》1995,62(6):703-705
Rectal swabs/stool specimens from 115 children (0–5 years) suffering with acute diarrhea were screened for non typhoidal salmonella
species. 7 (6%) patients were found to be positive for non typhoidal salmonella 4 (3.47%) were positive forS. paratyphi B and 3 (2.6%) were positive forS. typhimurium. Multidrug resistance was seen in 57 percent of the strains. All strains were sensitive to Ciprofloxacin. All strains were
resistant to Ampicillin followed by Ciprofloxacin. All strains were resistant to Ampicillin followed by Gentamycin (43%),
Kanamycin (43%), Tetracycline (43%), Streptomycin (28.5%) and Chloramphenicol (28.5%). 相似文献
7.
Sheela R Geraghty Susan M Pinney Gopalan Sethuraman Ashwini Roy-Chaudhury Heidi J Kalkwarf 《Ambulatory Pediatrics》2004,4(3):226-231
OBJECTIVE: Over 3% of infants born annually in the United States are from a multiple gestation pregnancy, yet there is little data published about the feeding practices of their mothers. The objectives of this study were to determine and compare the rates of breast milk feeding of mothers of multiples and mothers of singletons. METHODS: Stratified random sampling (n = 686) on the basis of plurality of pregnancy and gestational age at delivery was performed on a 1999 birth certificate database in the greater Cincinnati area. We collected information about infant feeding during the first 6 months of life using a retrospective, self-administered questionnaire and phone interview from mothers of term singletons (TS), preterm singletons (PS), term multiples (TM), and preterm multiples (PM). Data were analyzed using chi-square and logistic or multiple regression. RESULTS: We obtained feeding information from 346 mothers (n = 81 TS, 80 PS, 90 TM, and 95 PM). By 3 days postpartum, PM provided breast milk less often than all other groups: TS = 69%, PS = 66%, TM = 73%, PM = 57% (P =.035). Among mothers who initiated breast milk feeding, the geometric mean duration of at least some breast milk feeding was significantly shorter for PM than for all other groups: TS = 23 weeks, PS = 19 weeks, TM = 24 weeks, and PM = 12 weeks (P =.002). CONCLUSIONS: Further evaluation of the potential causes for the lower breast milk feeding rates among PM is needed to develop effective intervention strategies and increase the number of preterm multiple gestation infants receiving breast milk. 相似文献
8.
Yu Ni Adam A. Szpiro Michael T. Young Christine T. Loftus Nicole R. Bush Kaja Z. LeWinn Sheela Sathyanarayana Daniel A. Enquobahrie Robert L. Davis Mario Kratz Annette L. Fitzpatrick Jennifer T. Sonney Frances A. Tylavsky Catherine J. Karr 《Environmental health perspectives》2021,129(4)
Background: Limited data suggest air pollution exposures may contribute to pediatric high blood pressure (HBP), a known predictor of adult cardiovascular diseases.Methods: We investigated this association in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) study, a sociodemographically diverse pregnancy cohort in the southern United States with participants enrolled from 2006 to 2011. We included 822 mother–child dyads with available address histories and a valid child blood pressure measurement at 4–6 y. Systolic (SBP) and diastolic blood pressures (DBP) were converted to age-, sex-, and height-specific percentiles for normal-weight U.S. children. HBP was classified based on SBP or DBP percentile. Nitrogen dioxide () and particulate matter in aerodynamic diameter () estimates in both pre- and postnatal windows were obtained from annual national models and spatiotemporal models, respectively. We fit multivariate Linear and Poisson regressions and explored multiplicative joint effects with maternal nutrition, child sex, and maternal race using interaction terms.Results: Mean and in the prenatal period were 10.8 [standard deviation (SD): 0.9] and 10.0 (SD: 2.4) ppb, respectively, and 9.9 (SD: 0.6) and 8.8 (SD: 1.9) ppb from birth to the 4-y-old birthday. On average, SBP percentile increased by 14.6 (95% CI: 4.6, 24.6), and DBP percentile increased by 8.7 (95% CI: 1.4, 15.9) with each increase in second-trimester . averaged over the prenatal period was only significantly associated with higher DBP percentiles [ 11.6 (95% CI: 2.9, 20.2)]. Positive associations of second-trimester with SBP and DBP percentiles were stronger in children with maternal folate concentrations in the lowest quartile ( 0.05 and 0.07, respectively) and associations with DBP percentiles were stronger in female children ( 0.05). We did not detect significant association of , road proximity, and postnatal with any outcomes.Conclusions: The findings suggest that higher prenatal exposure, particularly in the second trimester, is associated with elevated early childhood blood pressure. This adverse association could be modified by pregnancy folate concentrations. https://doi.org/10.1289/EHP7486 相似文献
9.
Asif Padiyath M.D. Paul Gribben B.S. Joseph R. Abraham B.S. Ling Li M.D. Ph.D. Sheela Rangamani M.D. Andreas Schuster M.D. David A. Danford M.D. Gianni Pedrizzetti Ph.D. Shelby Kutty M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(2):203-210
We investigated intermodality agreements of strains from two‐dimensional echocardiography (2DE) and cardiac magnetic resonance (CMR) feature tracking (FT) in the assessment of right (RV) and left ventricular (LV) mechanics in tetralogy of Fallot (TOF). Patients were prospectively studied with 2DE and CMR performed contiguously. LV and RV strains were computed separately using 2DE and CMR‐FT. Segmental and global longitudinal strains (GLS) for the LV and RV were measured from four‐chamber views; LV radial (global radial strain [GRS]) and circumferential strains (GCS) measured from short‐axis views. Intermodality and interobserver agreements were examined. In 40 patients (20 TOF, mean age 23 years and 20 adult controls), LV, GCS showed narrowest intermodality limits of agreement (mean percentage error 9.5%), followed by GLS (16.4%). RV GLS had mean intermodality difference of 25.7%. GLS and GCS had acceptable interobserver agreement for the LV and RV with both 2DE and CMR‐FT, whereas GRS had high interobserver and intermodality variability. In conclusion, myocardial strains for the RV and LV derived using currently available 2DE and CMR‐FT software are subject to considerable intermodality variability. For both modalities, LV GCS, LV GLS, and RV GLS are reproducible enough to warrant further investigation of incremental clinical merit. 相似文献
10.