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排序方式: 共有2315条查询结果,搜索用时 0 毫秒
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Fabrice Bonnet MD Hungta Chen PhD Andrew Cooper PhD Marίlia B. Gomes MD Linong Ji MD Paul Leigh MA Larisa Ramirez MD Marina V. Shestakova MD Iichiro Shimomura MD Afrah Siddiqui MBBS Fengming Tang MS Jiten Vora Hirotaka Watada MD Kamlesh Khunti MD 《Diabetes, obesity & metabolism》2021,23(10):2336-2343
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D. Scott Lim MD Robert L. Smith MD Firas Zahr MD Abhijeet Dhoble MD Roger Laham MD Mohamad Lazkani MD Susheel Kodali MD Chad Kliger MD James Hermiller MD Amit Vora MD Ian J. Sarembock MB ChB MD William Gray MD Samir Kapadia MD Adam Greenbaum MD Andrew Rassi MD David Lee MD Adnan Chhatriwalla MD Pinak Shah MD Josep Rodés-Cabau MD Homam Ibrahim MD Lowell Satler MD Howard C. Herrmann MD Paul Mahoney MD Charles Davidson MD George Petrossian MD Mayra Guerrero MD Konstantinos Koulogiannis MD Leo Marcoff MD Linda Gillam MD The CLASP IID Pivotal Trial Investigators 《Catheterization and cardiovascular interventions》2021,98(4):E637-E646
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S C Toal B U Vajifdar A K Gupta A M Vora Y Y Lokhandwala 《Heart (British Cardiac Society)》2002,87(1):37-40
Objective: To evaluate the efficacy of single dose intravenous adenosine in differentiating atrioventricular nodal re-entrant tachycardia (AVNRT) from concealed pathway mediated atrioventricular re-entrant tachycardia (AVRT) using surface ECG at the bedside. 相似文献
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Twenty six patients with portal hypertension of different aetiologies were studied for endoscopic evidence of congestive gastroduodenopathy and histological evidence of congestive gastropathy and jejunopathy. Per oral biopsies of jejunum were taken by Watson's capsule. Normal biopsy tissues obtained from the antrum (26), fundus (10), and jejunum (26) were used as controls. Endoscopy showed congestive changes in the fundus (17 cases), antrum (17), and duodenum (4). Duodenopathy correlated with changes in the antrum but not in the fundus. Histology showed an increase in the size and number of vessels in the jejunal villi ('congestive jejunopathy') in 22 patients. These correlated with histological evidence of gastropathy in the fundus but not in the antrum. The incidence of congestive jejunopathy did not correlate with the Child-Pugh score in patients with cirrhosis or with the number of sclerotherapy sessions received. Congestive jejunopathy is part of the spectrum of congestive gastroenteropathy and occurs at least as frequently as changes in the stomach and duodenum. The clinical import of these jejunal changes remains to be explained. 相似文献
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Interleukin-4 (IL-4) is a potent mediator of growth and differentiation of cells of several hematopoietic lineages. Interleukin-5 (IL-5) is a lineage-specific hematopoietic growth factor that stimulates the production of eosinophils and eosinophil colonies from normal human bone marrow cells. By using somatic cell hybrids and in situ chromosomal hybridization, we localized the IL-4 and IL-5 genes to human chromosome 5 at bands q23-31, a chromosomal region that is frequently deleted [del(5q)] in patients with myeloid disorders. By in situ hybridization, the IL-4 and IL-5 genes were found to be deleted in the 5q- chromosome of four patients with refractory anemia (RA) or therapy-related acute nonlymphocytic leukemia (t-ANLL), who had a del(5q). Thus a small segment of chromosome 5 contains IL-4, IL-5, IL- 3, and GM-CSF as well as other genes such as CD14 and EGR1. Our findings that each of these genes was deleted in the 5q- chromosome suggest that loss of function of one or more of these genes may play an important role in the pathogenesis of hematologic disorders associated with a del(5q). 相似文献
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BACKGROUND: Conflicting views are reported on the association between advancing age and gradually diminishing concentrations of serum total testosterone in men. The putative loss of diurnal rhythm in serum total testosterone in older men is reported to be in part due to low concentrations in the morning when compared to concentrations found in young men. We have measured total, free and bioavailable testosterone along with SHBG in samples taken every 30 min throughout a 24-h period in 10 young and eight middle-aged men. RESULTS: Both young and middle-aged men displayed a significant diurnal rhythm in all variables, with a minimum fall of 43% in total testosterone from peak to nadir in all subjects. Subjecting the data to a time series analysis by least squares estimation revealed no significant difference in mesor (P = 0.306), amplitude (P = 0.061) or acrophase (P = 0.972) for total testosterone between the two groups. Comparing bioavailable testosterone in the two groups revealed no significant difference in mesor (P = 0.175) or acrophase (P = 0.978) but a significant difference (P = 0.031) in amplitude. Both groups display a significant circadian rhythm (middle-aged group P < 0.001; young group P = 0.014). Free testosterone revealed a highly significant rhythm in both the young group (P < 0.001) and the middle-aged group (P = 0.002), with no significant difference between the groups in mesor (P = 0.094) or acrophase (P = 0.698). Although analysis of the SHBG data revealed a significant rhythm in the young group (P = 0.003) and the older group (P < 0.001), the acrophase occurred in the mid afternoon in both groups (15.12 h in the young and 15.40 h in the middle-aged). The older men had a significantly greater amplitude (P = 0.044) but again no significant difference was seen in mesor (P = 0.083) or acrophase (P = 0.477) between the two groups. Acrophases for total, bioavailable and free testosterone occurred between 07.00 h and 07.30 h; for SHBG the acrophase occurred at 15.12 h in the young group and 15.40 h in the middle-aged group. CONCLUSIONS: The study suggests that the diurnal rhythm in these indices of androgen status is maintained in fit, healthy men into the 7th decade of life. 相似文献
79.
Dvorak AM; Tepper RI; Weller PF; Morgan ES; Estrella P; Monahan-Earley RA; Galli SJ 《Blood》1994,83(12):3600-3612
We used light and electron microscopy to analyze the eyelid inflammation that develops in transgenic mice that overexpress interleukin-4 (IL-4; Tepper et al, Cell 62:457, 1990). Analysis of alkaline Giemsa-stained plastic sections examined by light microscopy (Dvorak et al, J Exp Med 132:558, 1970), as well as by routine transmission electron microscopy, indicated that the mast cells in the inflammatory eyelid lesions were undergoing piecemeal degranulation, a form of secretion in which the cells' cytoplasmic granules exhibit characteristic morphologic changes that are thought to be associated with the prolonged, vesicle-mediated release of the granules' constituents. Moreover, by using a newly reported enzyme affinity-gold method, which stains histamine based on binding to diamine oxidase-gold (Dvorak et al, J Histochem Cytochem 41:787, 1993), we show that these activated mast cells had released much of their histamine content. The eyelid lesions also exhibited increased numbers of mast cells; interstitial fibrosis, particularly around cutaneous nerves and blood vessels; activated fibroblasts; focal axonal damage; venules with endothelial cells containing numerous vesiculo-vacuolar organelles; and infiltrates of neutrophils and eosinophils. Our findings illustrate that overexpression of the IL-4 gene in vivo can result in eyelid lesions associated with piecemeal degranulation of mast cells, as well as tissue fibrosis and a variety of other pathologic changes. These results also represent the first direct morphologic evidence for histamine secretion by mast cells in vivo. 相似文献
80.