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141.
R. J. Bosma A. J. Kwakernaak J. J. Homan van der Heide P. E. de Jong G. J. Navis 《American journal of transplantation》2007,7(3):645-652
Obesity is a risk factor for renal graft loss. Higher body mass index (BMI) in native kidneys is associated with glomerular hyperfiltration. Whether higher BMI in renal transplants is associated with hyperfiltration is unknown. We investigated the impact of BMI on renal hemodynamics 1 year post-transplant. We analyzed glomerular filtration rate (GFR, (125)I-iothalamate) and effective renal plasma flow (ERPF, (131)I-hippurate) in 838 kidney transplants. Data were analyzed for all patients and for the subpopulation without diabetes. Long-term impact of BMI and renal hemodynamics were explored by Cox-regression. With higher BMI GFR and filtration fraction (FF) increased significantly. Multivariate analysis supported impact of BMI on GFR (adjusted r(2) of the model 0.275) and FF (adjusted r(2) of the model 0.158). This association was not explained by diabetes mellitus. On Cox-regression analysis, lower GFR and higher FF were independent determinants of overall graft loss and graft loss by patient mortality. Lower GFR and higher BMI were determinants of death-censored graft loss, with borderline contribution of higher FF. In renal transplants higher BMI is independently associated with higher GFR and FF one year posttransplant, suggesting glomerular hyperfiltration with altered afferent-efferent balance. Mechanisms underlying the long-term prognostic impact of hyperfiltration deserve further exploration. 相似文献
142.
We analyze whether the political system and its stability are related to cross-country differences in health. We apply factor analysis on various national health indicators for a large sample of countries over the period 2000–2005 and use the outcomes of the factor analysis to construct two new health measures, i.e., the health of individuals and the quality of the health care sector. Using a cross-country structural equation model with various economic and demographic control variables, we examine the relationship between the type of regime and political stability on the one hand and health on the other. The political variables and the control variables are measured as averages over the period 1980–1999. Our results suggest that democracy has a positive relationship with the health of individuals, while regime instability has a negative relationship with the health of individuals. Government instability is negatively related to individual health via its link with the quality of the health care sector, while democracy is positively related with individual health through its link with income. Our main findings are confirmed by the results of a panel model and various sensitivity tests. 相似文献
143.
C Casanova C G Cote J M Marin J P de Torres A Aguirre-Jaime R Mendez L Dordelly B R Celli 《The European respiratory journal》2007,29(3):535-540
The 6-min walking distance (6MWD) test is used in clinical practice and research into patients with chronic obstructive pulmonary disease (COPD). However, little is known about natural long-term change in this parameter. The 6MWD was measured at baseline and then annually for 5 yrs in 294 patients with COPD and its annual rate of decline was determined. Forced expiratory volume in one second (FEV1) was also measured and the relationship between changes in both markers was explored. At baseline, the median 6MWD was 380 m (range 160-600 m). It declined by 19% (16 m.yr(-1)) over the 5 yrs compared with baseline in patients with American Thoracic Society/European Respiratory Society stage III COPD (FEV1 30-50% predicted) and by 26% (15 m.yr(-1)) in patients with stage IV COPD (FEV1 <30% pred). Over the 5-yr follow-up, the proportion of patients with a minimal clinically significant decline of 54 m increased with the severity of the disease. It was 24% in stage II, 45% in stage III, and 63% in stage IV disease. In contrast, the rate of decline of FEV1 was greater in patients with milder airflow obstruction and lesser in patients with lower absolute FEV1 values. In conclusion, the 6-min walking distance test provides increasingly useful information as the severity of chronic obstructive pulmonary disease increases. 相似文献
144.
A. B. Soares P. R. Faria L. A. Magna M. E. P. Correa C. A. de Sousa O. P. Almeida M. L. Cintra 《Journal of oral pathology & medicine》2005,34(6):368-373
BACKGROUND: Graft-vs.-host disease (GVHD) is the major cause of morbidity and mortality in patients undergoing allogeneic Bone Marrow Transplantation (BMT). The aim of our study was to identify the most relevant histological features for diagnosis of chronic Graft-vs.-Host Disease (cGVHD) in oral mucosa and minor salivary glands of 25 patients, as well as to evaluate the immunophenotype of the inflammatory cells. METHODS: Sixteen patients that were submitted to allogeneic BMT but did not present cGVHD were selected as a control group. The sections were studied on H & E and CD68, CD45, CD4, CD8, CD20 staining. RESULTS: The most frequent histologic findings in oral mucosa at the day of diagnosis of cGVHD were: hydropic degeneration of the basal layer of the epithelium, apoptotic bodies, lymphocytic infiltration, and focal or total cleavage between the epithelial and connective tissue. In the labial salivary glands (LSG), lymphocytic infiltration, acinar loss and fibrosis were the main alterations. Cytotoxic CD8-T cells and macrophages were predominant both in the epithelium and connective tissue, as well as in minor salivary glands. CONCLUSIONS: Histological features were useful in the diagnosis of oral cGVHD. It is suggested that CD8-T cells and macrophages play important role in the pathogenesis of the disease. 相似文献
145.
A Parra F Gabi?o A Ramírez H Valencia I Coria A Espinosa de los Monteros 《Contraception》1991,44(5):541-547
The study was undertaken to analyze the basal and metoclopramide-stimulated serum PRL levels in healthy parous women users (group 1, n = 12) and non-users (group 2, n = 12) of a TCu-380 IUD. All women had regular menses and were studied between days 18 to 22 of their cycle; none had lactated nor regularly ingested any type of medication during the last six months. After a 10-12 hour overnight fast, peripheral venous blood samples were obtained through an indwelling catheter at -30, -15 and 0 minutes and at 60, 90 and 120 minutes after oral metoclopramide (10 mg). There were no significant differences in serum PRL between both groups, in basal levels nor throughout the test, whether analyzing the mean values at each sampling time, the sum of PRL levels from 60-120 minutes, or the peak levels. No correlation was observed between PRL levels and any of the clinical or obstetric characteristics of the women in both groups. Serum progesterone was greater than or equal to 4.0 ng/ml in all women. Thus, the use of alpha TCu-380 IUD did not induce any significant changes in basal nor in stimulated serum PRL levels. 相似文献
146.
147.
Dipyridamole and RA-642 inhibit the production of superoxide anion and free radical damage to rat lens. 总被引:1,自引:0,他引:1
J P De la Cruz A Sintas A Moreno J Garcia-Campos F Sanchez de la Cuesta 《Pharmacology & toxicology》1991,69(3):201-204
We studied the effects of dipyridamole and RA-642 on the production of superoxide anions and on oxygen radicals-induced lipid peroxidation in lens tissue homogenates from normal rats and rats given dipyridamole or RA-642 intraperitoneally. Superoxide production was evaluated by phenazine methosulphate (PMS)-induced nitroblue tetrazolium (NBT) reduction and lipid peroxidation by ferrous sulfate and ascorbic acid (FeAs)-induced malondialdehyde (MDA) production. Dipyridamole and RA-642 showed an inhibitory effect on both assays in the experiments with lens tissue homogenates from untreated or treated rats. The extent of inhibition, however, was significantly higher in pyrimidopyrimidinic-treated rats (range of inhibition at different times of incubation was 18% versus 23-57% for dipyridamole and 14% versus 73-80% for RA-642 in the assay of MDA production, and 10% versus 33-37% for dipyridamole and 2.5% versus 11-32% for RA-642 in the assay of NBT reduction). Concentrations of dipyridamole and RA-642 in lens tissue from treated animals could not be determined (less than 0.001 micrograms/mg of tissue). Although both compounds inhibited lipid peroxidation induced by oxygen free radicals, the mechanism of action might include the role of adenosine as a mediator. 相似文献
148.
149.
B Cornette de Saint-Cyr L J Garey G F Maillard C Aharoni 《Journal of plastic, reconstructive & aesthetic surgery》2007,60(12):1277-1286
We describe a novel procedure for an anatomically-based face lift to correct vertical vectors in the ageing face. It has the advantage of surgical simplicity, minimal tissue removal and minimal risk. It provides an effective readjustment of cheek volume and correction of periorbital hollowness. Natural facial expression is preserved largely because there is no change in the position of the lateral canthus. The cheek is mobilised subperiosteally through a blepharoplasty incision. A second dissection is made via a short temporal incision, to join the infraorbital dissection. A Hagedorn needle is then inserted through a point inferior to the lateral canthus and in line horizontally with the nasal ala. It is passed to the orbital incision, charged with a loop of suture material, and pulled down again to the cheek incision, from where it is pushed back to the orbit to suspend the cheek. The upper border of orbicularis oculi is fixed firmly to the temporalis aponeurosis at the level of the temporal incision. We now frequently use an Endotine Midface device for fixation. Of the first 150 patients, results were excellent or good in 145. This represents a revival of the subperiosteal mask lift, and abandons the use of endoscopic techniques. In spite of its simplicity, the operation involves subperiosteal dissection as well as delicate eyelid surgery that necessitate plastic surgical skill. 相似文献
150.
Anna Spada†‡ Farzin Reza-Elahi†‡ rea Lania†‡ Atanasio Pandiella†† Monique Bassetti†† Nicoletta Bazzoni† Paloma Gil de Alamo† Giovanni Faglia† 《Journal of neuroendocrinology》1991,3(1):51-56
The effect of thyrotrophin-releasing hormone (TRH) on intracellular free Ca2+ concentration, [Ca2+)i, was investigated with the fluorescent dye fura-2 in cell suspensions obtained from 13 human growth hormone-secreting adenomas and 6 adrenocorticotrophin-secreting adenomas. Preoperatively, 9 out of 13 acromegalic patients showed a positive growth hormone response to TRH administration while none of the 6 patients with Cushing's disease had a plasma adrenocorticotrophin increase after TRH injection. In all the growth hormone-secreting adenomas the addition of TRH (100 nM) caused a significant rise in [Ca2+]i (from a resting level of 133±40 (±SD) to a value of 284±119 nM at 100 nM TRH, n = 42; P<0.001). The transient induced by TRH was found to have a dual origin, one due to Ca2+ mobilization from intracellular stores which was maintained in presence of EGTA (3mM) and verapamil (10 μM) and a plateau phase due to Ca2+ influx from the extracellular media. Somatostatin (0.1 μM) lowered both resting [Ca2+]i and TRH-induced transients. The effect of gonadotrophin-releasing hormone on [Ca2+]i was evaluated on cell suspensions obtained from 6 growth hormone-secreting adenomas. Gonadotrophin-releasing hormone (100 nM) caused a marked rise in [Ca2+]i (from 179±25 to 283±15nM) on the cell suspension obtained from the only in vivo responsive adenoma while it was ineffective in the remaining 5. Although TRH was ineffective in modifying plasma adrenocorticotrophin levels in all patients with Cushing's disease, in 5 out of 6 tumors the addition of 100 nM TRH caused a significant rise in [Ca2+]i (from 102.5 ± 36 to 163±66 nM, n = 22; P < 0.005). However, the effect of TRH on [Ca2+]i was significantly lower than that caused by arginine vasopressin, a physiological stimulator of adrenocorticotrophin release ([Ca2+]i values; 145±78 nM at 100 nM TRH versus 300±140 at 10 nM arginine vasopressin, n = 15; P<0.05). Moreover, the effect of arginine vasopressin on [Ca2+]i was detectable at concentrations as low as 0.1 nM while TRH was effective at concentrations higher than 1 nM. By contrast, gonadotrophin-releasing hormone was ineffective in increasing [Ca2]i in all the adrenocorticotrophin-secreting adenomas studied. Collectively, these data indicate that sensitivity to TRH is present in almost all the growth hormone- and adrenocorticotrophin-secreting adenomas independently of the responsiveness of the individual patients to the peptide. 相似文献