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81.
Chronic fissure-in-ano: A randomized study comparing open and subcutaneous lateral internal sphincterotomy 总被引:4,自引:4,他引:4
J. B. Kortbeek M.D. F.R.C.S. Dr. J. M. Langevin M.D. F.R.C.S. R. E. H. Khoo M.D. F.R.C.S. J. A. Heine M.D. F.R.C.S. 《Diseases of the colon and rectum》1992,35(9):835-837
A prospective study comparing open and subcutaneous lateral internal sphincterotomy for chronic anal fissure was conducted. One hundred twelve patients were randomized to open (n=54) or subcutaneous (n=58) sphincterotomy. There was no significant difference in acute complications between the subcutaneous (8.6 percent) and open (7.4 percent) groups. Postoperative length of stay was significantly shorter for the subcutaneous group (1.7±0.2 days) than for the open group (2.3±0.1 days;P
<0.001). Although the response rate to a pain questionnaire was <50 percent, the data suggest a lower level of postoperative pain in the subcutaneous group. Fissure healing was similar between the subcutaneous (96.6 percent) and open (94.4 percent) groups. We conclude that subcutaneous lateral internal sphincterotomy for chronic fissure-in-ano is effective and may result in significantly less postoperative discomfort, shorter postoperative lengths of stay, and a comparable rate of complications compared with the open technique. 相似文献
82.
Low density lipoprotein rich in oleic acid is protected against oxidative modification: implications for dietary prevention of atherosclerosis. 总被引:14,自引:1,他引:14 下载免费PDF全文
S Parthasarathy J C Khoo E Miller J Barnett J L Witztum D Steinberg 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(10):3894-3898
Oxidative modification of low density lipoprotein (LDL) enhances its potential atherogenicity in several ways, notably by enhancing its uptake into macrophages. In vivo studies in the rabbit show that inhibition of LDL oxidation slows the progression of atherosclerotic lesions. In the present studies, rabbits were fed either a newly developed variant sunflower oil (Trisun 80), containing more than 80% oleic acid and only 8% linoleic acid, or conventional sunflower oil, containing only 20% oleic acid and 67% linoleic acid. LDL isolated from the plasma of animals fed the variant sunflower oil was highly enriched in oleic acid and very low in linoleic acid. These oleate-rich LDL particles were remarkably resistant to oxidative modification. Even after 16-hr exposure to copper-induced oxidation or 24-hr incubation with cultured endothelial cells, macrophage uptake of the LDL was only marginally enhanced. The results suggest that diets sufficiently enriched in oleic acid, in addition to their LDL-lowering effect, may slow the progression of atherosclerosis by generating LDL that is highly resistant to oxidative modification. 相似文献
83.
Hormonal requirements for growth and differentiation of ob17 preadipocyte cells in vitro 总被引:2,自引:0,他引:2
G Ailhaud E Amri C Cermolacce P Djian C Forest D Gaillard P Grimaldi J Khoo R Négrel G Serrero-Davé 《Diabète & métabolisme》1983,9(2):125-133
The ob17 cell line is a clonal line established from epididymal fat pads of C57 BL/6J ob/ob mice. After conversion into adipose-like cells, ob17 presents both the morphological and biochemical properties of mature rodent fat cells. The adipose conversion process is best represented by a stochastic model in which a pool of stem cells (adipoblasts) gives rise to clusters of adipose cells and to additional stem cells that remain in the population. The role of the different factors involved in the adipose conversion process of ob17 cells is discussed, i.e. 1) mitogenic factors, that enhance the number of committed cells (ACF or adipose conversion factor(s)) 2) lipogenic factors, that enhance the expression of adipocyte enzyme markers (insulin) and 3) adipogenic factors, that are obligatory requirements for adipose conversion (triiodothyronine, growth hormone and other pituitary factors). 相似文献
84.
Characterization of the interleukin 3 receptor 总被引:2,自引:0,他引:2
A variety of homobifunctional crosslinking agents have been used to gain insight into the nature of the murine interleukin 3 (mIL-3) receptor. When [125I]mIL-3 was cross-linked to receptor sites on the surfaces of intact B6SUtA1 cells with disuccinimidyl suberate (DSS), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed the existence of two radiolabeled species with molecular weights of 140 (p140) and 70 (p70) kd (after subtraction of [125I]mIL-3). The relative intensities of the two bands did not change when the [125I]mIL-3 concentration was varied, confirming Scatchard results which suggested only one affinity class. However, when [125I]mIL-3 was crosslinked to intact cells and then incubated at 37 degrees C, the intensity of p140 decreased relative to p70, suggesting a conversion of p140 to p70. This conversion could be inhibited by sodium azide, methylamine, and bacitracin and could also be prevented by first boiling for 1 min in 2% SDS and 5% 2-mercaptoethanol. The putative protease that carried out this apparent conversion appeared to be associated both with plasma membranes prepared from these cells and also with solubilized receptors. Moreover, when p140, crosslinked with both dithiobis succinimidylpropionate and glutaraldehyde, was purified and reelectrophoresed under reducing conditions, p70 could be generated. N-glycanase digestion of p140 and p70 revealed a similar level of N-linked carbohydrate, which upon closer study appeared to consist of two chains, a 3-kd and an 8-kd moiety. Consistent with this data, we propose that the receptor is a 140-kd glycoprotein that is cleaved to a 70-kd surface protein upon mIL-3 binding and chemical crosslinking. 相似文献
85.
K H Park T Huang F F Correia M Krystal 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(13):5537-5541
A simple protocol for the rescue of a synthetic genome into a paramyxovirus has been developed. First, a synthetic Sendai virus-like RNA, containing the antisense coding region of the chloramphenicol acetyltransferase gene replacing the coding region of the Sendai virus genome, was transcribed from a cDNA. When introduced into cells that are infected with Sendai virus, this RNA construct was transcribed, replicated, and packaged into infectious virions. The addition of infected cell extract to the RNA prior to transfection markedly enhanced levels of chloramphenicol acetyltransferase expression and rescue. However, this enhancement is not due to encapsidation of the RNA into nucleocapsids as the RNA remains nuclease-sensitive. Uninfected cell extract also enhances expression and rescue efficiency, implying involvement of a cellular factor(s) with the synthetic viral-like RNA construct that allows for enhanced polymerase recognition. This system should allow for the dissection of the various cis-acting RNA signals within the paramyxovirus genome. 相似文献
86.
IgE alone stimulates mast cell adhesion to fibronectin via pathways similar to those used by IgE + antigen but distinct from those used by Steel factor 总被引:1,自引:0,他引:1 下载免费PDF全文
Lam V Kalesnikoff J Lee CW Hernandez-Hansen V Wilson BS Oliver JM Krystal G 《Blood》2003,102(4):1405-1413
We recently demonstrated that immunoglobulin E (IgE), in the absence of cross-linking agents, activates signaling pathways in healthy murine bone marrow-derived mast cells (BMMCs) and that this activation enhances BMMC survival, at least in part, via secretion of autocrine-acting cytokines. We report herein that IgE alone also triggers the adhesion of both BMMCs and connective tissue mast cells (CTMCs) to the connective tissue component, fibronectin (FN). This adhesion occurs to the same extent as that triggered by optimal levels of Steel factor (SF) or IgE + antigen (IgE + Ag) and is mediated by an increased avidity of the integrin very late antigen 5 (VLA-5). Moreover, this IgE-induced adhesion, which is prolonged compared with that elicited by SF or IgE + Ag, requires phosphatidylinositol 3-kinase (PI3K), phospholipase C gamma (PLCgamma), and extracellular calcium but not extracellular-regulated kinase (Erk) or p38. Interestingly, we found, using the calcium channel blocker, 2-APB (2-aminoethoxydiphenyl borate) and Lyn-/- BMMCs that both IgE- and IgE + Ag-induced adhesion to FN require extracellular calcium entry, whereas SF does not. Furthermore, our data suggest that FN acts synergistically with IgE to prolong intracellular phosphorylation events and to enhance IgE-induced inflammatory cytokine production and BMMC survival. 相似文献
87.
Identification of low density lipoprotein as a regulator of Fc receptor-mediated phagocytosis. 总被引:3,自引:0,他引:3 下载免费PDF全文
R D Bigler M Khoo S Lund-Katz L Scerbo M Esfahani 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(13):4981-4985
Optimal expression of the high-affinity Fc receptor for IgG (FcRI) by the human monocyte cell line U-937 requires the presence of low density lipoprotein (LDL), and neither cholesterol nor high density lipoprotein can provide the component necessary for optimal FcRI expression. Here we show that FcR-mediated phagocytosis also requires LDL. U-937 cells were cultured in medium containing interferon gamma and either fetal calf serum (FCS) or delipidated FCS (DLFCS). The phagocytosis of IgG-coated erythrocytes was measured by a colorimetric assay. U-937 cells cultured in DLFCS medium had less than 16% of the phagocytic activity of cells cultured in normal FCS medium. Phagocytosis of IgG-coated erythrocytes could be inhibited 85% by the addition of murine IgG2a myeloma protein (5 micrograms/ml). U-937 cells cultured in DLFCS medium supplemented with pure cholesterol in ethanol (10 micrograms/ml) had only 30% of the phagocytic activity of cells grown in FCS medium. Addition of very low density lipoprotein (0.2 mg of protein per ml) to DLFCS medium also failed to increase phagocytosis. However, the addition of LDL (0.2 mg of protein per ml) to DLFCS medium restored 90% of the phagocytic activity. Since neither pure cholesterol nor very low density lipoprotein restored normal phagocytic function to U-937 cells despite a normalization of cellular cholesterol content, the restoration of phagocytosis observed with LDL replacement cannot be explained by mere delivery of cholesterol by LDL. Thus, LDL is required for the expression of FcRI and FcR-mediated phagocytosis by U-937 cells and may be an important regulator of phagocytic activity of monocytes and macrophages in vivo. 相似文献
88.
Objective
To summarize trends in status epilepticus (SE) in the United States by age, race, sex, admission source, disposition, incidence rates, and mortality.Methods
Data from US National Hospital Discharge Survey were used from 1979 to 2010 to identify discharges with SE and common etiologies and complications of SE using International Classification of Diseases, 9th Revision, Clinical Modifications codes. Temporal trends in the incidence and in-hospital mortality of SE were examined with respect to age, sex, and race.Results
We identified 760,117 discharges with SE over 32 years. The incidence of SE increased from 3.5 to 12.5/100,000 between 1979 and 2010, without a significant change in in-hospital mortality. Higher incidence, earlier age of onset, and higher mortality were observed among males. Age stratification revealed a “U-shaped” distribution with higher incidence at age <10 years (14.3/100,000) and age >50 years (approaching 28.4/100,000). In-hospital mortality, however, was the lowest (2.6 %) at age <10 years and approached 20.2 % with age ≥80 years. The incidence of SE was higher among blacks (13.7/100,000), compared to whites (6.9/100,000) and other races (7.4/100,000). Mortality, however, was lower among blacks (7.2 %) compared to whites and other races (9.8 and 9.2 %, respectively). Black men had the highest incidence (15.0/100,000), relatively younger age of onset (39.3 years) and the lowest mortality (5.6 %). A net temporal decline in the reported prevalence of epilepsy, central nervous system infections, and traumatic brain injury was noted among SE cohort.Conclusions
The incidence of SE increased nearly fourfold with relatively unchanged mortality. Gender and racial disparities exist in the incidence of SE, and age is an important predictor of mortality. 相似文献89.
Thet Zaw Lam Alfred K. Ranganathan Dwarakanathan Aung Soe Yu Khoo Tien K. 《Clinical rheumatology》2020,39(9):2501-2513
Clinical Rheumatology - This review appraises the current literature on carcinogenic risks in anti-neutrophilic cytoplasmic autoantibody (ANCA) associated vasculitis (AAV). Patients with AAV are... 相似文献
90.
Bridget D. Mathison Lindsey L. Kimble Kerrie L. Kaspar Christina Khoo Boon P. Chew 《Nutrition Research》2014
Consumption of polyphenol-rich foods is associated with lower risk from many chronic diseases. We hypothesized that a single dose of cranberry beverage would improve indices of oxidative stress, inflammation, and urinary antibacterial adhesion activity in healthy humans. Six males and 6 females (18-35 years; body mass index, 19-25 kg/m2) consumed placebo, cranberry leaf extract beverage, or low-calorie cranberry juice cocktail (LCJC) once in a randomized, double-blind, placebo-controlled cross-over experimental design trial. The washout period between beverages was 1 week. Blood was collected 0, 2, 4, 8, and 24 hours after beverage consumption for measuring oxidative and inflammatory biomarkers. Urine was collected at 0, 0 to 3, 3 to 6, 6 to 9, 9 to 12, and 24 hours postintervention to assess antibacterial adhesion activity. Consumption of cranberry leaf extract beverage elevated (P < .05) blood glutathione peroxidase activity, whereas LCJC consumption increased (P < .05) glutathione concentrations and superoxide dismutase activity compared with placebo. Cranberry leaf extract beverage and LCJC consumption had no effect on the inflammatory biomarkers measured as compared with placebo. At 0 to 3 hours postconsumption, urine from participants who consumed cranberry beverages had higher (P < .05) ex vivo antiadhesion activity against P-fimbriated Escherichia coli compared with placebo. An acute dose of cranberry beverages improved biomarkers of antioxidant status and inhibition of bacterial adhesion in urine. 相似文献