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31.
C Diaz de la Guardia F Alba C de Linares D Nieto-Lugilde J López Caballero 《Journal of investigational allergology & clinical immunology》2006,16(1):24-33
Cupressaceae pollen has been cited in recent years as one of the major airborne allergens of the Mediterranean region, prompting us to conduct an exhaustive analysis on the aerobiological behaviour of this pollen in the Iberian Peninsula and the repercussion that it has had on the atopic population. The aerobiological study, performed from 1996 to 2003 in the city of Granada (S. Spain), used a volumetric Hirst collector. The results indicate that this pollen is present in the air most of the year, registering a high incidence during the winter months. This type of pollen behaved irregularly in the air, fluctuating yearly, seasonally, and within the same day. Temperature and humidity were the parameters that most directly influence the variability of this allergen, while rainfall prior to flowering increased pollen production. The predictive models used estimated a high percentage of the levels reached over the short term by this pollen in the atmosphere of Granada. The clinical study performed with atopic patients showed that some 30% of the population with pollinosis are sensitive to Cupressaceae pollen, affecting people of both genders equally. On the other hand, the most sensitive age group was 21-40 years of age, while children and the elderly registered almost negligible values. Most of the sensitive subjects resided within the city or in the metropolitan area, where environmental pollution reached high levels, while the pathology was found to be less frequent in rural zones. The most frequent symptoms were upper-respiratory ailments and an asthmatic profile. 相似文献
32.
Ana C Mendes M Madalena Caldeira Claudia Silva Shawn C Burgess Matthew E Merritt Filipe Gomes Cristina Barosa Teresa C Delgado Fatima Franco Pedro Monteiro Luis Providencia John G Jones 《Magnetic resonance in medicine》2006,56(5):1121-1125
Menthol glucuronide was isolated from the urine of a healthy 70-kg female subject following ingestion of 400 mg of peppermint oil and 6 g of 99% [U-(13)C]glucose. Glucuronide (13)C-excess enrichment levels were 4-6% and thus provided high signal-to-noise ratios (SNRs) for confident assignment of (13)C-(13)C spin-coupled multiplet components within each (13)C resonance by (13)C NMR. The [U-(13)C]glucuronide isotopomer derived via direct pathway conversion of [U-(13)C]glucose to [U-(13)C]UDP-glucose was resolved from [1,2,3-(13)C(3)]- and [1,2-(13)C(2)]glucuronide isotopomers derived via Cori cycle or indirect pathway metabolism of [U-(13)C]glucose. In a second study, a group of four overnight-fasted patients (63 +/- 10 kg) with severe heart failure were given peppermint oil and infused with [U-(13)C]glucose for 4 hr (14 mg/kg prime, 0.12 mg/kg/min constant infusion) resulting in a steady-state plasma [U-(13)C]glucose enrichment of 4.6% +/- 0.6%. Menthol glucuronide was harvested and glucuronide (13)C-isotopomers were analyzed by (13)C NMR. [U-(13)C]glucuronide enrichment was 0.6% +/- 0.1%, and the sum of [1,2,3-(13)C(3)] and [1,2-(13)C(2)]glucuronide enrichments was 0.9% +/- 0.2%. From these data, flux of plasma glucose to hepatic UDPG was estimated to be 15% +/- 4% that of endogenous glucose production (EGP), and the Cori cycle accounted for at least 32% +/- 10% of GP. 相似文献
33.
Renal dysfunction after myocardial revascularization. 总被引:5,自引:0,他引:5
Pedro E Antunes David Prieto J Ferr?o de Oliveira Manuel J Antunes 《European journal of cardio-thoracic surgery》2004,25(4):597-604
OBJECTIVES: In this study, we evaluate the incidence of and analyse the pre and intraoperative risk factors for the development of postoperative renal dysfunction (PRD), and the impact of such an event on perioperative mortality and on hospital length of stay. In addition, we sought to investigate the influence of a mildly increased serum creatinine (1.3-2.0 mg/dl) on perioperative mortality and morbidity. METHODS: The study included 2445 consecutive patients who had no pre-existing renal disease (creatinine or=2.1 mg/dl with a preoperative-to-postoperative increase >or=0.9 mg/dl. Univariate and multivariate analyses were performed where appropriate. RESULTS: Global 30-day mortality was 0.7%. The incidence of PRD was 5.6% (136 patients). Mortality for patients who experienced PRD was 8.8 vs. 0.1% for patients who did not (P<0.001). PRD increased the length of hospital stay by 3.4 days (7.6 vs. 11.0 days; P<0.001), and patients who needed haemodialysis (11%) had a perioperative mortality of 33.3% and a mean hospital length of stay of 16 days. Multivariable logistic regression identified the following variables as independent predictors of PRD: age (P=0.017; odds ratio (OR) 1.3 per 10 years), angina class III/IV (P=0.003; OR 1.7); cardiopulmonary bypass time (P=0.007; OR 1.01 per minute); preoperative serum creatinine levels: group 1 (1.3-1.6 mg/dl (P<0.001; OR 5.5)) and group 2 (1.7-2.0 mg/dl (P<0.001; OR 14.2)). Finally, a mild elevation of the preoperative creatinine level (1.3-2.0 mg/dl) increased significantly the probability of perioperative mortality, low cardiac output, haemodialysis and prolonged hospital stay. CONCLUSIONS: Although the likelihood of PRD in patients without pre-existing renal dysfunction is relatively low, it dramatically increases mortality, morbidity and length of stay after CABG. Mildly elevated (>1.2 mg/dl) preoperative serum creatinine level significantly increases the perioperative mortality and morbidity. 相似文献
34.
Nelson Wolosker Guilherme Yazbek José Ribas Milanez de Campos Paulo Kauffman Augusto Ishy Pedro Puech-Leão 《Clinical autonomic research》2007,17(3):172-176
Background Sympathectomy is the treatment of choice for primary hyperhidrosis. One curious occurrence that is difficult to explain from
an anatomophysiological point of view in cases of video-assisted thoracoscopic sympathectomy (VATS) for the treatment of palmar
hyperhidrosis (PH) is the observed improvement in plantar hyperhidrosis (PLH). Nevertheless, current reports on VATS rarely
describe the effect on PLH or just give superficial data. The aim of this study was to prospectively investigate, how surgery
affects PLH in patients with PH and PLH over one-year period.
Methods From May 2003 to January 2004, 70 consecutive patients with combined PH and PLH underwent VATS at the T2, T3, or T4 ganglion
level (47 women and 23 men, with mean age of 23 years).
Results Immediately after the operation, all the patients said they were free from PH episodes, except for two patients (2.8%) who
suffered from continued PH. Compensatory hyperhidrosis (CH) of various degrees was observed in 58 (90.6%) patients after one
year. Only 13 (20.3%) suffered from severe CH. There was a great initial improvement in PLH in 50% of the cases, followed
by progressive regression, such that only 23.4% still presented that improvement after one year. The number of cases without
overall improvement increased progressively (from 17.1% to 37.5%) and the numbers with slight improvement remained stable
(32.9–39.1%). Of the 24 patients with no improvement after one year, 6 patients graded plantar sweating worse.
Conclusion Patients with PH and PLH who undergo VATS to treat their PH present a good initial improvement in PLH that reduces to a lower
level of improvement after the one-year period. 相似文献
35.
Miguel Cordeiro Pedro Monteiro Dinis Vieira Francisco Parente Nuno Devesa José Moura Luís Providência 《Revista portuguesa de cardiologia》2004,23(3):399-441
Pulmonary embolism (PE) is an important health problem and often a major clinical challenge, not only because of the low specificity of its clinical manifestations but also because of the increasing number of medical circumstances that are risk factors for this illness and the importance of early identification, since prompt and appropriate treatment can decrease mortality from this disease by about 25%. In recent years research on PE has been extensive, directed mainly at trying to determine and characterize its risk factors, establish new clinical probability algorithms, develop new diagnostic methods and put existing ones into perspective, seek new therapeutic approaches (pharmacological and non-pharmacological), and above all establish protocols that can guide the clinician from the stage of clinical suspicion to measures to prevent recurrence. It was the authors' aim to review the most significant literature on this subject, in order to produce a text that reflects the state of the art concerning PE and that can be used as a guide in the clinical approach to this pathology. 相似文献
36.
BACKGROUND: In this study we investigated the cellular absorption rates, antioxidant and free radical scavenging activity of vitamin C-lipid metabolites. The absorption was measured in a human lymphoblastic cell line using a spectrophotometric technique. MATERIAL/METHODS: Cellular vitamin C levels in the human lymphoblastic H9 cell line were measured using the 2,4-dinitrophenylhydrazine spectrophotometric technique. Free radical scavenging activity of vitamin C-lipid metabolites was measured by the reduction of 1,1-diphenyl-2-picryl hydrazyl (DPPH) to 1,1-diphenyl-2-picryl hydrazine. Vitamin C-lipid metabolite scavenging of peroxyl radical oxygen reactive species (ORAC) was determined by fluorescence spectrophotometry. RESULTS: Compared to ascorbic acid (AA), calcium ascorbate (CaA), and calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C), vitamin C-lipid metabolites (PureWay-C) were more rapidly absorbed by the H9 human T-lymphocytes. The vitamin C-lipid metabolites (PureWay-C) also reduced pesticide-induced T-lymphocyte aggregation by 84%, while calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C) reduced aggregation by only 34%. The vitamin C-lipid metabolites (PureWay-C) demonstrated free radical scavenging activity of nearly 100% reduction of DPPH at 20 microg/ml and oxygen radical scavenging of over 1200 micro Trolox equivalents per gram. CONCLUSIONS: These data demonstrate that the vitamin C-lipid metabolites (PureWay-C) are more rapidly taken-up and absorbed by cells than other forms of vitamin C, including Ester-C. This increased rate of absorption correlates with an increased protection of the T-lymphocytes from pesticide toxicities. Further, vitamin C-lipid metabolites (PureWay-C) are a potent antioxidant and have significant free radical scavenging capabilities. 相似文献
37.
Pedro Moral Elisabetta Marini Esther Estebanup Giuseppa Elisa Mameli Valeria Succa Giuseppe Vona 《American journal of human biology》2002,14(1):21-28
Four communities from Guahibo of Venezuela were analyzed for the genetic variants of nine erythrocyte enzymes and five serum proteins. Of the 14 loci determined, four were monomorphic. Significant frequency differentiation among communities, was present for ESD and TF markers. In general, Guahibo allele frequencies are in the variation ranges described for South American groups. The analysis indicates a relatively higher affinity of Guahibos with other Venezuelan groups within an irregular pattern of genetic distances that are likely related to the complex demographic history of the South American groups. Genetic diversity estimates reveal a moderate degree of genetic structure between the four Guahibo communities. This intra‐tribal variability in Guahibo appears to be lower than in Venezuelan Piaroa but higher than in other Amerindians and could be attributed to a combined effect of low population size and relative isolation of communities. At a continental level, the distribution of genetic diversity is consistent with preferential population movements along the eastern and western coastal areas. Am. J. Hum. Biol. 14:21–28, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
38.
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40.
Raquel Carreira Ana Duarte Pedro Monteiro Maria Sancha Santos Ana Cristina Rego Catarina R Oliveira Lino M Gon?alves Luís A Providência 《Revista portuguesa de cardiologia》2004,23(11):1447-1455
Ischemia negatively affects mitochondrial function by inducing the mitochondrial permeability transition (MPT). The MPT is triggered by oxidative stress, which occurs in mitochondria during ischemia as a result of diminished antioxidant defenses and increased reactive oxygen species production. It causes mitochondrial dysfunction and can ultimately lead to cell death. Therefore, drugs able to minimize mitochondrial damage induced by ischemia may prove to be clinically effective. We analyzed the effect of carvedilol, a beta-blocker with antioxidant properties, on mitochondrial dysfunction. Carvedilol decreased levels of TBARS (thiobarbituric acid reactive substances), an indicator of oxidative stress, which is consistent with its antioxidant properties. Regarding cell death by apoptosis, although ischemia did increase caspase-8-like activity, there were no changes in caspase-3-like activity, which is activated downstream of caspase-8; this may indicate that the apoptotic cascade is not activated by 60 minutes of ischemia. We conclude that carvedilol protects ischemic mitochondria by preventing oxidative mitochondrial damage, and, by so doing, it may also inhibit the formation of the MPT pore. 相似文献