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991.
Background
Beta‐2 microglobulin (B2M) and alpha‐2 macroglobulin (A2M) play key roles in the immune system. The aim of this study was to compare B2M and A2M levels in patients with different periodontal diseases.Methods
Eighty patients (20 periodontally healthy, 20 with gingivitis, 20 with chronic periodontitis and 20 with generalized aggressive periodontitis) were enrolled in the study. The analysis of B2M and A2M was performed on gingival crevicular fluid (GCF) using an enzyme‐linked immunosorbent assay in GCF.Results
The total levels of B2M and A2M were statistically lower in the periodontally healthy group than in the other groups (p < 0.05) and significantly higher in the generalized aggressive periodontitis group compared to the other groups (p < 0.05).Conclusions
B2M and A2M play key roles in the balance between periodontal health and disease. It is proposed that tissues release B2M and A2M to stop inflammation and inhibit the proliferation of microorganisms and this may be the reason for the high levels of B2M and A2M in the generalized aggressive periodontitis and chronic periodontitis groups. B2M and A2M are assumed to be user‐friendly and cost‐effective markers for periodontal disease to identify asymptomatic diseases. 相似文献992.
993.
Xia B Guo HJ Crusius J Deng CS Meuwissen S Pena A 《World journal of gastroenterology : WJG》1998,4(3):252-255
AIM:To determine the tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6) and soluble interleukin 2 receptor (sIL-2r) from peripheral blood mononuclear cells (PBMC) in 25 Chinese patients with ulcerative colitis and 20 healthy controls.METHODS:PBMC were isolated by density gradient centrifugation of heparinized blood and cultures for 24 or 48 hours by stimulation with LPS or PHA. TNF-alphaand sIL-2r were measured by ELISA method and IL-6 measured by biossay.RESULTS:TNF-alphaproduction stimulated by LPS and sIL-2r production by PHA in ulcerative colitis were significantly lower than in healthy controls (TNF-alpha509(46-7244)ng/L vs 1995(117-18 950)ng/L, P < 0.05; sIL-2r 320U/mlplus minus 165U/ml vs 451U/mlplus minus 247U/ml, P < 0.05).Spontaneous TNF-alphaand sIL-2r production were not significantly different between ulcerative colitis and controls (TNF-alpha304(46-7044)ng/L vs 215(46-4009)ng/L,P > 0.05; sIL-2r 264U/mlplus minus 115U/ml vs 236U/mlplus minus139U/ml, P>0.05). IL-6 production by spontaneous release from PBMC in ulcerative colitis group was 109U/mlplus minus 94U/ml vs 44U/mlplus minus 39U/ml for those in healthy controls, P < 0.01. IL-6 stimulated by LPS in ulcerative colitis group was (261U/ml plus minus 80U/ml) higher than in healthy controls (102U/mlplus minus 54U/ml, P < 0.01). No correlation of TNF-alpha, IL-6, sIL-2r production was found to disease activity, disease location and medication.CONCLUSION:Cytokine production from PBMC was also disturbed in Chinese patients with ulcerative colitis. 相似文献
994.
W Chia P W Rigby 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(11):6638-6642
Mouse cells are nonpermissive for simian virus 40 (SV40); replication of viral DNA is undetectable and progeny virions are not produced. Infection leads instead to the establishment of stably transformed cell lines in which viral DNA is covalently integrated into cellular DNA. We have followed the fate of SV40 DNA in infected mouse cells to define steps in viral DNA metabolism that precede integration. A novel high molecular weight form of SV40 DNA is synthesized shortly after infection by a process sensitive to the inhibition of DNA replication. This DNA represents polymers in which viral genomes are organized as tandem "head-to-tail" arrays. Recombination can be demonstrated with mutant viruses, but the recombination frequency is not high enough to account for the synthesis of polymers by recombination between infecting genomes. We conclude that polymers are synthesized by DNA replication and that they then recombine with one another. We believe that the polymers also recombine with cellular DNA and are thus the precursor to integrated viral DNA. Such a model accounts directly for the high frequency of tandemly duplicated viral insertions in transformed cells and also leads to experimentally testable predictions. 相似文献
995.
Changes in body composition in patients with left ventricular systolic dysfunction initiated on beta-blocker therapy
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Lee Ingle Alan S Rigby Sean Carroll Ron Butterly Rod F King Carlton B Cooke John GJF Cleland Andrew L Clark 《Experimental & Clinical Cardiology》2007,12(1):46-47
BACKGROUND: Increasing body mass index, cholesterol and body fat are associated with a better prognosis in patients with left ventricular systolic dysfunction (LVSD). Beta-blocker usage is associated with changes in body composition and increased body fat. The present study investigated 12-month changes in body composition in patients with LVSD initiated on beta-blocker therapy. METHODS: The relation between beta-blocker use and body composition was evaluated in 91 patients (75% male) with LVSD. Body composition was assessed by bioelectrical impedance. RESULTS: Seventeen patients died during the study period. There was no statistical difference among beta-blocker usage, beta-blocker type, or changes in body fat, basal metabolic rate, impedance, fat-free mass, fat mass and total body water. There were no significant differences between any of these measures and beta-blocker usage. CONCLUSION: After 12 months, changes in body composition were not found to be influenced by initiation of beta-blocker therapy in patients with LVSD. 相似文献
996.
997.
Amanda B Trombini Claudinéia CS Franco Rosiane A Miranda Júlio C de Oliveira Luiz F Barella Kelly V Prates Aline A de Souza Audrei Pavanello Ananda Malta Douglas L Almeida Laize P Tófolo Kesia P Rigo Tatiane AS Ribeiro Gabriel S Fabricio Juliane R de Sant’Anna Marialba AA Castro-Prado Helenir Medri de Souza Hely de Morais Paulo CF Mathias 《Cancer biology & therapy》2015,16(6):958-964
It is known that antidiabetic drug metformin, which is used worldwide, has anti-cancer effects and can be used to prevent cancer growth. We tested the hypothesis that tumor cell growth can be inhibited by early treatment with metformin. For this purpose, adult rats chronically treated with metformin in adolescence or in adulthood were inoculated with Walker 256 carcinoma cells. Adult rats that were treated with metformin during adolescence presented inhibition of tumor growth, and animals that were treated during adult life did not demonstrate any changes in tumor growth. Although we do not have data to disclose a molecular mechanism to the preventive metformin effect, we present, for the first time, results showing that cancer growth in adult life is dependent on early life intervention, thus supporting a new therapeutic prevention for cancer. 相似文献
998.
JORGE CAMUÑAS DAVENDRA MEHTA JOHN IP ELANA PE J. ANTHONY GOMES 《Pacing and clinical electrophysiology : PACE》1993,16(7):1380-1385
We describe a new approach to tolal pectoral implantation of cardioverter defibrillators with an endocardial defibrillation lead system. Endocardial lead configuration used was an FDA approved right atrial-superior vena cavo defibriliation spring electrode, right ventricular bipolar sensing electrode, and a pectoral patch. Endocardial leads were implanted via a cephalic or an axillary venesection. Pectoral patch was placed in a sabmuscular position. In case of failure to obtain satisfactory thresholds, a small intercostal thoracofomy was performed via fhe same skin incision and patch placed over the epicardium instead of submuscular position and used with Ihe right atrial spring electrode. The device was implanted in the pectoral region, submuscularly, over the patch. Sixteen consecutive patients underwent this approach. With a submascular patch, adequate defibrillation thresholds (< 15 joules [J]) were obtained in 14 (87.5%) patients. In the other two, defibrillation thresholds of ≤ 15) were obtained with a epicardial patch. Pectoral implantation of the device was feasible in all 16 patients and none needed repositioning. Average postimplant hospital stay was 5 days. During follow-up period (average 5 months), none of the patients reported any major local symptoms and no problems have been encountered in device interrogation. Thus, total pectoral implantation of the cardioverter defibrillator including the patch, leads, and the device is feasible. Furthermore, in case of foilure to obtain adequate defibrillotjon thresholds with submuscular patch, an epicardial patch can easily be implanted and allows 100% successful defibrillation at energy levels of ≤ 15 J with right atrial patch configuration. 相似文献
999.
PURPOSE: An array of statistical methods is available for 2 x 2 contingency table analysis. These include odds ratios, reliability coefficients and the Chi-squared test. This paper continues the '2 x 2' theme but extends it to look at diagnostic testing. The setting is primary care, the disease is urological cancer. METHOD: Several statistical indices are discussed to measure diagnostic efficiency; these include sensitivity, specificity and the likelihood ratio. The latter can be converted into a flexible 'weight of evidence', which is equivalent to the naive Bayes' discriminant. RESULTS: The utility of the naive Bayes' discriminant is illustrated in a primary care setting. CONCLUSION: The naive Bayes' discriminant has proved to be the most durable of statistical discriminants in medical diagnosis. The reason for its durability is ease of use. Despite a concern about independence, it remains a popular choice as a diagnostic aid. 相似文献
1000.
Theresa Ryan Schultz BA RRT RN Margaret Priestly MD Ann Marie Cahill MD Kevin M. Baskin MD Linda A. Napoli MBA RRT Shawn Colborn AS RRT Robin D. Kaye MD 《Journal of Radiology Nursing》2004,23(2)
A girl weighing 26 kg came with a one-day history of progressive hypoxia. Physical examination was significant for clubbing, cyanosis, and tachypnea. Inhaled nitric oxide (NO) was administered at 20 ppm to selectively dilate pulmonary vessels as a temporizing treatment for refractory hypoxemia. A chest CT demonstrated a left lower lobe AVM. On the third day of admission, a pulmonary angiogram and embolization was performed by interventional radiology. At the end of the procedure, PaO2/FiO2 increased to 330 from 40, and the angiographic run demonstrated a 70% reduction in the size of the AVM. 相似文献