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81.
Jorge Polónia Nuno Carvalho Loide Barbosa José A Silva 《Revista portuguesa de cardiologia》2006,25(7-8):693-704
INTRODUCTION: It is still controversial whether subjects with white-coat hypertension (WCHT) exhibit higher cardiovascular risk compared to normotensive subjects (NT). In subjects with WCHT it is not known whether the abnormal blood pressure (BP) reaction in the office also occurs at other times of day, particularly on arising and immediately after waking, i.e. the times at which the majority of cardiovascular events are reported to occur. OBJECTIVE AND METHODS: To evaluate with 24h ambulatory BP measurement the values of morning BP surge, BP on arising and BP variability in subjects with WCHT in comparison with age-, gender- and weight-matched normotensives (BP) and untreated sustained hypertensives (BP). RESULTS: Groups of BP, WCHT and BP were matched for age, gender and body weight: BP: n=69, age 49 +/- 7 years, 54 % female, BMI 26 +/- 1, casual BP 126/79 +/- 5/4 mmHg, daytime BP 124/80 +/- 6/6 mmHg; WCHT: n=74, age 52 +/- 8 years, 57% female, BMI 26 +/- 2, casual BP 152/95 +/- 7/7 mmHg, daytime BP 126/80 +/- 5/6 mmHg; HT: n=79, age 53 +/- 7 years, 56% female, BMI 27 +/- 2, casual BP 154/97 +/- 9/8 mmHg, daytime BP 143/89 +/- 12/10 mmHg. Of the three groups, subjects with WCHT exhibited BP on arising (121/81 +/- 13/8 mmHg) similar to that of NTs (120/80 +/- 13/9 mmHg, NS), both significantly lower than that of HTs (137/92 +/- 17/10 mmHg, p < 0.01), suggesting the absence of an alerting BP reaction in WCHT at that time. By contrast, subjects with WCHT showed higher values of systolic morning BP surge vs. NTs (25 +/- 10 vs. 22 +/- 11 mmHg, p < 0.05), both lower than that observed in hypertensives (33 +/- 11 mmHg, p < 0.01 vs. NT and WCHT) and greater daytime variability (systolic BP standard variation), i.e. 12 2 vs. 10 +/- 2 mmHg, p < 0.05, both lower than that observed in hypertensives (14 +/- 3 mmHg, p < 0.01 vs. NT and WCHT). CONCLUSIONS: Although subjects with WCHT did not show any alerting blood pressure reaction on arising, morning BP surge and BP variability were greater in these subjects than in control normotensives, although lower than sustained hypertensives. Although this is still speculative, we cannot exclude the possibility that even a slight increase in morning BP surge might in the long term constitute an additional load on the circulation that could increase cardiovascular risk in subjects with WCHT compared to matched normotensives. 相似文献
82.
Matthew A Roberts Merlin C Thomas Dharsh Fernando Neil Macmillan David A Power Francesco L Ierino 《Nephrology, dialysis, transplantation》2006,21(6):1611-1617
BACKGROUND: Advanced glycation end products (AGEs) have biological properties that may contribute to the premature cardiovascular mortality of haemodialysis patients. This study examines the hypothesis that low molecular weight forms of fluorescent AGEs (LMW fluorescence) predict mortality in haemodialysis patients. METHODS: The LMW fluorescence was measured in 85 patients treated with chronic haemodialysis and prospectively followed for 4 years. The primary outcome of all-cause mortality was assessed using Cox proportional hazards regression model. RESULTS: At the end of the follow-up period 37 (44%) patients died. The median LMW fluorescence level was 24.2 arbitrary units (range: 10.6-148.1 AU) and the receiver operator characteristic (ROC) curve cut-off for mortality was 37.0 AU. The LMW fluorescence predicted death both as a binary variable at the ROC cut-off, and as a continuous log-transformed variable when adjusted for age, albumin and C-reactive protein (CRP). Adjusted for age, albumin and CRP, the hazard ratio for mortality was 3.05 (1.41-6.60, P = 0.005) for LMW fluorescence as a binary variable and 2.71 per log unit (1.37-5.38, P = 0.004) as a continuous log-transformed variable. CONCLUSION: The low molecular weight forms of AGEs predict mortality in patients receiving chronic haemodialysis, and may be important in the mechanisms leading to atherosclerosis and inflammation in such patients. 相似文献
83.
Guilherme Janson Karina Santana Cruz Donald G Woodside Angelos Metaxas Marcos Roberto de Freitas José Fernando Castanha Henriques 《American journal of orthodontics and dentofacial orthopedics》2004,126(4):451-463
The objective of this study was to evaluate the dentoskeletal changes consequent to orthodontic treatment in subjects with Class II subdivision malocclusions, treated with asymmetric extractions, compared with a normal-occlusion control group. The sample consisted of 3 groups, with 30 subjects in each: normal-occlusion subjects (group 1), untreated Class II subdivision subjects (group 2), and Class II subdivision patients treated with asymmetric extractions (group 3). All subjects had a full complement of permanent teeth at the beginning of treatment. The average ages of the subjects were 22.42, 15.76, and 18.57 years, respectively, in groups 1, 2, and 3. Measurements of relative differences in the spatial position of dental and skeletal bilateral landmarks were obtained from the submentovertex and posteroanterior cephalometric (PA) radiographs. The t test for independent samples was used to compare group 1 with groups 2 and 3 at different times. Results from the submentovertex radiograph showed that asymmetric extractions in Class II subdivision malocclusions will maintain the differences in the anteroposterior positions of right and left, maxillary and mandibular first molars, as would be expected with the treatment protocols used. There were no significant skeletal changes that could be attributed to the treatment approaches investigated or transverse collateral effects with the asymmetric mechanics used. It was also demonstrated that treatment of Class II subdivision malocclusions with asymmetric extractions produced corrections of maxillary and mandibular dental midline deviations with the midsagittal plane, without canting the occlusal plane or any other investigated horizontal plane, as seen in the PA radiograph. Treatment of Class II subdivision malocclusions with asymmetric extractions constitutes a beneficial approach to this problem. 相似文献
84.
Anna Letícia Soares Marinez de Oliveira Sousa Luci Maria Dusse Ana Paula Salles Moura Fernandes Marcelo Carvalho Lasmar Bethania Alves Novelli Geralda de Fátima Guerra Lages Maria das Gra?as Carvalho 《Blood coagulation & fibrinolysis》2007,18(5):395-399
This study aimed to investigate whether endothelial cells are damaged and to evaluate fibrinolytic system function in patients with type 2 diabetes. For this proposal, plasma levels of von Willebrand factor (an endothelial marker of injury), homocysteine (an inductor of endothelial injury), D-dimer (a marker of coagulation cascade activation) and plasminogen activator inhibitor-1 (a fibrinolysis marker) were measured in individuals with both type 2 diabetes and high blood pressure, with type 2 diabetes, with high blood pressure and in healthy control individuals. No significant differences among groups were observed for von Willebrand factor and homocysteine plasma levels. The type 2 diabetes and high blood pressure group presented a significant difference to the other groups for D-dimer and also presented high values for plasminogen activator inhibitor-1. The high blood pressure group and type 2 diabetes group presented separately higher values of plasminogen activator inhibitor-1 compared with the control group. High levels of D-dimer and plasminogen activator inhibitor-1 in patients with type 2 diabetes and high blood pressure with normoalbuminuria therefore indicate a state of hypercoagulability and hypofibrinolysis, despite no evident microvascular injury supported by normal levels of von Willebrand factor and homocysteine. 相似文献
85.
Jessica Lasky-Su Tobias Banaschewski Jan Buitelaar Barbara Franke Keeley Brookes Edmund Sonuga-Barke Richard Ebstein Jacques Eisenberg Michael Gill Iris Manor Ana Miranda Fernando Mulas Robert D Oades Herbert Roeyers Aribert Rothenberger Joseph Sergeant Hans-Christoph Steinhausen Eric Taylor Kaixin Zhou Margaret Thompson Philip Asherson Stephen V Faraone 《Neuropsychopharmacology》2007,62(9):985-990
BACKGROUND: Previous research found an association between single nucleotide polymorphisms (SNPs) in the promoter region of DRD4 and statistically derived phenotypes generated from attention-deficit/hyperactivity disorder (ADHD) symptoms. We sought to replicate this finding by using the same methodology in an independent sample of ADHD individuals. METHODS: Four SNPs were genotyped in and around DRD4 in 2631 individuals in 642 families. We developed a quantitative phenotype at each SNP by weighting nine inattentive and nine hyperactive-impulsive symptoms. The weights were selected to maximize the heritability at each SNP. Once a quantitative phenotype was generated at each SNP, the screening procedure implemented in PBAT was used to select and test the five SNPs/genetic model combinations with the greatest power to detect an association for DRD4. RESULTS: One of the four SNPs was associated with the quantitative phenotypes generated from the ADHD symptoms (corrected p-values = .02). A rank ordering of the correlation between each of the ADHD symptoms and the quantitative phenotype suggested that hyperactive-impulsive symptoms were more strongly correlated with the phenotype; however, including inattentive symptoms was necessary to achieve a significant result. CONCLUSIONS: This study partially replicated a previous finding by identifying an association between rs7124601 and a quantitative trait generated from ADHD symptoms. The rs7124601 is in linkage disequilibrium (LD) with the SNPs identified previously. In contrast to the previous study, this finding suggests that both hyperactive-impulsive and inattentive symptoms are important in the association. 相似文献
86.
Daniela Accorsi-Mendon?a Fernando M A Corrêa Ana M de Oliveira 《Journal of Smooth Muscle Research》2006,42(1):21-31
This study was designed to study the effects of angiotensin converting enzyme inhibitors (ACEI) following treatment with trandolapril (0.3 mg kg(-1) day(-1)) on carotid arterial responsiveness in normotensive Wistar rats. Carotid arteries were obtained from control or trandolapril-treated animals and mounted in an isolated organ bath. Reactivity to angiotensin II (Ang II), phenylephrine (Phe) and KCl was studied. Agonist concentration-response curves were constructed in either the absence or presence of the endothelium or after incubation with L-NAME (10(-6) M), HOE140 (10(-7) M) or indomethacin (10(-5) M). Trandolapril treatment decreased the Ang II and Phe potencies in carotid arteries, but did not affect the maximal response. The KCl responses (potency and Emax) were similar in both control and trandolapril-treated arteries. The absence of endothelium increased the response to both agonists in control and trandolapril-treated arteries; however, the inhibitory component from the endothelial layer of the Phe response was greater in trandolapril-treated animals than in control animals. The presence of L-NAME or HOE140 abolished the changes in the potency values of trandolapril-treated animals. The presence of indomethacin did not change the effect of trandolapril on the potency values of both agonists. We conclude that trandolapril treatment decreased the carotid arterial reactivity in normotensive rats and that this effect is endothelium-dependent. Furthermore, the involvement of B(2)-receptors and NO production, but not of prostaglandins, is suggested in this mechanism. 相似文献
87.
88.
Karina M S Freitas Marcos Roberto de Freitas José Fernando Castanha Henriques Arnaldo Pinzan Guilherme Janson 《American journal of orthodontics and dentofacial orthopedics》2004,125(4):480-487
Treatment stability is one of the most important objectives in orthodontics, but, despite decades of research, it is still agreed that the stability of aligned teeth is variable and largely unpredictable. This study aimed to evaluate the relapse of mandibular anterior crowding in patients treated without mandibular premolar extraction. The sample comprised 40 patients of both sexes with Class I or II malocclusions who received nonextraction treatment in the mandibular arch with edgewise mechanics. Lateral cephalograms and dental casts of each patient were obtained at pretreament, posttreatment, and 5 years postretention. Relapse of mandibular anterior crowding was assessed, and associations between this relapse and other clinical factors were also investigated. Mandibular anterior crowding was measured by the Little irregularity index, and the data were evaluated by the Mann-Whitney test. The mean relapse of mandibular anterior crowding was 1.95 mm (26.54%) over the long term. No clinical factor studied was predictive of crowding relapse in the long term. 相似文献
89.
90.
The Distally Based Sural Artery Flap for Ankle and Foot Coverage 总被引:1,自引:0,他引:1
Tahseen A. Cheema MD Ehab S. Saleh MD Alex F. De Carvalho MD 《The Journal of foot and ankle surgery》2007,46(1):40-47
The sural artery flap is a distally based fasciocutaneous flap that has many advantages to offer for coverage in the foot and ankle area. It has the largest arc of rotation of all the regional flaps and does not require sacrifice of any major artery, and moderate-to-large-sized defects can be covered adequately. The dissection technique is simple, and donor site morbidity is minimal. We report our experience with 17 cases. Age range was from 13 to 56 years. Ten (59%) defects were posttraumatic, 3 (17%) were related to reconstructive surgery of the foot or tendon Achilles', 2 (11%) resulted from tumor resection, and 1 each were from infection and gunshot wound. The smallest flap was 6 x 4 cm and the largest was 15 x 12 cm, with the average size being 11 x 7.5 cm. In 5 cases, the donor site was closed primarily, and in other cases, split-thickness skin graft was needed. The short saphenous vein was included in the pedicle in all cases. There was no incidence of complete flap necrosis. Follow-up ranged from 3 to 30 months. Two cases (12%) developed partial superficial necrosis. In 1 case, there was partial wound dehiscence that needed debridement and repair. Another case had postoperative discharge, which subsided after removal of the calcaneal plate. None of the patients complained of any functional problem related to loss of sensation along the lateral border of the foot. The sural island flap is a reliable, safe, and easy method of providing soft tissue coverage in the area of the foot and ankle. 相似文献