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31.
32.
K. Jonderko A. Kasicka-jonderko B. Krusiec-świdergoł M. Dzielicki L. Strój M. Doliński K. Doliński B. Błońska-fajfrowska 《Neurogastroenterology and motility》2005,17(6):800-809
AIM: To check on reproducibility of parameters of the cutaneous electrogastrogram registered at a close or a distant time span. METHODS: Twenty-two volunteers recruited by an advertisement (11 females and 11 males, median age 25 years, range: 18-35) underwent three surface electrogastrography examinations of which two were taken on consecutive days and the third one was accomplished at least 2 weeks before or after the two other sessions. The examination involved a 30-min fasted recording, followed by a 90-min postprandial registration after intake of a 394-kcal mixed solid-liquid test meal. RESULTS: Parameters of the electrogastrogram pertaining to the frequency of the gastric slow waves exhibited good to moderate reproducibility, whereas fair reproducibility characterized parameters expected to describe the power of gastric slow waves. With the exception of the difference fed minus fasted power (DeltaDP), in no instance was the medium term reproducibility any worse than the short term one. Categorical data analysis revealed that the relative time share of normogastria postprandially exhibited a better reproducibility than in the fasted period. The Cohen's kappa-value of 0.459 for the DeltaDP for the medium term reproducibility placed this parameter within the range of moderate agreement between repeat examinations. Of the two two-parameter combinations considered, the alliance of the fasted and fed normogastria performed worse than any of those parameters considered alone, whereas a combination of the DeltaDP with the fed-state normogastria revealed a kappa-value amounting to 0.510 for the medium term reproducibility. CONCLUSIONS: The feasibility of some electrogastrographic parameters to convey clinically useful information may be hampered by their fair reproducibility. Recoding of parameters of the cutaneous electrogastrogram from primary continuous to secondary categorical may help achieve a better agreement between repeat examinations. 相似文献
33.
Distension-induced gastric accommodation in functional dyspepsia: effect of autonomic manipulation 总被引:2,自引:0,他引:2
j. a. lunding o. h. gilja † t. hausken † a. bayati ‡ h. mattsson ‡ & a. berstad 《Neurogastroenterology and motility》2007,19(5):365-375
Functional dyspepsia (FD) is associated with impaired gastric accommodation and autonomic dysregulation. The aim of this study was to investigate the effects of autonomic manipulation on distension-induced gastric accommodation in subjects with and without FD, using a newly developed gastric barostat paradigm. Twelve healthy subjects (HS) and 18 subjects with FD had four barostat examinations each: no intervention, intravenous atropine (1 mg), vagal stimulation (mental relaxation with deep breathing) and acute stress stimulation (serial subtraction task). Intrabag pressure increased from 1 to 15 mmHg in 5 min (ramp phase), and was maintained at 15 mmHg for 5 min (tonic phase). Volume responses were analysed using predefined parameters. There were no significant group differences in accommodation variables between HS and subjects with FD. The FD group could be subdivided into two distinct subgroups: subgroup 1 (n = 7, 38%) with low maximum volume and accommodation rate, and subgroup 2 with normal accommodation (n = 11). In subgroup 1, but not in subgroup 2 atropine increased maximum volume and accommodation rate substantially. Neither mental stress nor mental relaxation changed any of the accommodation variables. In a subgroup of subjects with FD, impairment of distension-induced gastric accommodation can be improved by cholinergic blockade, but not by acute physiological autonomic manipulation. 相似文献
34.
George Lourenço PhD Sabine Meunier MD PhD Marie Vidailhet MD PhD Marion Simonetta‐Moreau MD PhD 《Movement disorders》2007,22(4):523-527
A decrease of heteronymous median nerve-evoked inhibition of corticospinal projections to forearm extensor muscles was reported in a group of 10 dystonic patients by Bertolasi and colleagues in 2003. Here we tested the excitability of corticomotoneuronal connections to both wrist extensor (ECR) and flexor (FCR) muscles after conditioning stimulation of median and also radial nerve at rest in a group of 25 patients with focal hand dystonia compared to 20 healthy subjects. We also investigated the effect of the wrist dystonic posture, either in flexion or in extension, on the afferent modulation of ECR and FCR motor evolved potentials (MEPs). The heteronymous (median-induced) but also homonymous (radial-induced) inhibitions (interstimuli intervals 13-21 ms) of ECR MEP size observed in healthy subjects were decreased in patients. In addition, homonymous (median-induced) facilitation of FCR MEP size was also decreased in patients while heteronymous inhibition (radial-induced) was not. Neither the involvement of the target muscle in the dystonic posture nor the origin of the afferent volley (from a dystonic muscle) influenced the degree of impairment of afferent modulation of the MEP. These findings support the view that a global abnormal somatosensory coupling in focal hand dystonia may contribute to an inadequate motor command to wrist muscles. 相似文献
35.
36.
Grafts of porcine intestinal submucosa for repair of cervical and abdominal esophageal defects in the rat. 总被引:2,自引:0,他引:2
Maria Francelina Lopes António Cabrita José Ilharco Pedro Pessa Jo?o Patrício 《Journal of investigative surgery》2006,19(2):105-111
Porcine small intestinal submucosa (SIS) is a cell-free collagen matrix that has demonstrated its ability as scaffold material for constructive remodeling of damaged or missing tissue. The purpose of this study was to evaluate the morphology and function of esophagoplasty in rat using a porcine SIS scaffold for the repair of a semi-circumferential defect in the cervical or in the abdominal esophagus. Sixty-seven rats underwent surgical excision of the anterior wall either of the cervical or of the abdominal esophagus and subsequent repair of the defect with an SIS patch graft. Outcomes of weight gain, signs of dysphagia, hematological and serum chemistry parameters, and barium swallow studies were used to assess the progress of healing and function over a 150-day time period. The grafts were studied for gross changes and histology at predetermined time points. Ninety-four percent of the SIS-treated rats survived, showing no significant differences in survival rate between groups. The grafted animals did well, without signs of dysphagia, and gaining weight. Barium swallow studies showed no evidence of fistula, significant stenosis, or diverticula. No hematological or serum biochemistry abnormalities were found. By 150 days, the SIS graft was replaced with esophageal-derived tissues. Specimens were completely lined by keratinized stratified squamous epithelium and showed complete regeneration of muscle fibers and scarce immunoreactivity for nerve. In the rat model, a patch graft technique using porcine SIS appears to induce esophageal regrowth either in cervical and abdominal esophagus. The repair mechanism occurred through a regenerative healing process. 相似文献
37.
Jo?o Maldonado Telmo Pereira Jorge Polónia Luís Martins 《Revista portuguesa de cardiologia》2006,25(7-8):709-714
BACKGROUND: Aerobic exercise training has been associated with beneficial effects on the cardiovascular system, improving arterial compliance, possibly related to a positive impact on the endothelium. The effects of competitive aerobic exercise are not so well documented. This prompted us to evaluate the possible modulation of arterial properties in a group of athletes and their response to the aging process. METHODS: 423 healthy males were enrolled in a cross-sectional study, 212 of whom were competitive athletes and 211 were controls. All underwent carotid-femoral pulse wave velocity (PWV) evaluation, and casual blood pressure and other relevant anthropometric data were evaluated. RESULTS: To control the effects of age, each group was divided into two subgroups with an age cut-point of 20 years. PWV was 6.3 +/- 0.9 m/s (athletes) vs. 7.0 +/- 1.0 m/s (controls) for ages <20 years, and 7.6 +/- 1.2 m/s (athletes) vs. 8.1 +/- 0.9 m/s (controls) for ages >20 years, with statistically significant differences in both comparisons. A linear regression model with logarithmic tendency analysis with age as the independent determinant of PWV revealed a different progression of age-related deterioration of aortic compliance between the two groups (athletes and controls). CONCLUSIONS: Our data documented better compliance indices in competition athletes compared with controls, which may reflect optimization of endothelial function. This improvement was age-dependent, being less pronounced as the athletes grow older, which could be due partially to sustained stretching effects on the arterial walls in long-term competitors. 相似文献
38.
Jorge Polónia Jo?o Maldonado Rui Ramos Susana Bertoquini Mary Duro Cristina Almeida Jo?o Ferreira Loide Barbosa José Alberto Silva Luís Martins 《Revista portuguesa de cardiologia》2006,25(9):801-817
BACKGROUND: Portugal has one of the highest mortality rates from stroke, a high prevalence of hypertension and probably a high salt intake level. AIM: To evaluate Portuguese salt intake levels and their relationship to blood pressure and arterial stiffness in a sample of four different adult populations living in northern Portugal. METHODS: A cross-sectional study evaluating 24-hour urinary excretion of sodium (24 h UNa+), potassium and creatinine, blood pressure (BP), and pulse wave velocity (PWV) as an index of aortic stiffness in adult populations of sustained hypertensives (HT), relatives of patients with previous stroke (Fam), university students (US) and factory workers (FW), in the context of their usual dietary habits. RESULTS: We evaluated a total of 426 subjects, mean age 50 +/- 22 years, 56% female, BMI 27.9+/-5.1, BP 159/92 mmHg, PWV 10.4+/-2.2 m/s, who showed mean 24h UNa+ of 202 +/- 64 mmol/d, corresponding to a daily salt intake of 12.3 g (ranging from 5.2 to 24.8). The four groups were: HT: n = 245, 49 +/- 18 years, 92% of those selected, 69% treated, BP 163/94 mmHg, PWV 11.9 m/s, 24 h UNa+ 212 mmol/d, i.e. 12.4 g/d of salt); Fam: n = 38, 64 +/- 20 years, 57 % of those selected, BP 144/88 mmHg, PWV 10.5 m/s, 24 h UNa+ 194 mmol/d, i.e. 11.1 g/d of salt; US: n = 82, 22 +/- 3 years, 57% of those selected, BP 124/77 mmHg, PWV 8.7 m/s, 24h UNa+ 199 mmol/d, i.e. 11.3 g/d of salt; FW: n = 61, 39 9 years, 47% of those selected, BP 129/79 mmHg, PWV 9.5 m/s, 24 h UNa+ 221 mmol/d, i.e. 12.9 g/d of salt. The ratio of urinary sodium/potassium excretion (1.9 (0.4) was significantly higher in HT than the other three groups. In the 426 subjects, 24h UNa+ correlated significantly (p < 0.01) with systolic BP (r = 0.209) and with PWV (r=0.256) after adjustment for age and BP. Multivariate analysis showed that BP, age and 24h UNa+ correlated independently with PWV taken as a dependent variable. CONCLUSIONS: Four different Portuguese populations showed similarly high mean daily salt intake levels, almost double those recommended by the WHO. Overall, high urinary sodium excretion correlated consistently with high BP levels and appeared to be an independent determining factor of arterial stiffness. These findings suggest that Portugal in general has a high salt intake diet, and urgent measures are required to restrict salt consumption in order to prevent and treat hypertensive disease and to reduce overall cardiovascular risk and events. 相似文献
39.
J Pedraz E Daudén Y Delgado-Jiménez I García-Río A García-Díez 《Journal of the European Academy of Dermatology and Venereology》2006,20(6):702-706
BACKGROUND: There are numerous studies that individually evaluate the efficacy/effectiveness and toxicity of drugs in the systemic treatment of psoriasis. On the contrary, we can hardly find studies that compare each other. OBJECTIVE: To evaluate and compare the effectiveness and toxicity of mycophenolate mofetil and cyclosporin in chronic plaque psoriasis through a prospective, sequential, cross-over, non-randomized, two-phase, open-label study. PATIENTS/METHODS: Eight patients (five women and three men; mean age 57, range 35-78) with moderate-to-severe chronic plaque psoriasis were included in the study. They were treated with oral mycophenolate mofetil (30 mg/kg/day) over a period of 16 weeks. Following a variable washout period and after a new outbreak of the disease, oral cyclosporin was introduced at a dose of 4 mg/kg/day. During both treatment regimens, follow-up visits were performed at 3, 8 and 16 weeks. RESULTS: In both groups, the PASI started to decrease once treatment was begun. Cyclosporin was faster and statistically a lot more effective than mycophenolate mofetil, reaching a higher number of complete remissions and better percentages of PASI improvement from baseline (45.7%, 60.2% and 60.5% at 3, 8 and 16 weeks respectively for mycophenolate mofetil, and 89.7%, 95.3% and 95.3% respectively at the same intervals for cyclosporin). Cyclosporin was also more predictable in its action as the percentage of improvement along the follow-up visits had a much wider range for mycophenolate mofetil. Overall, the tolerability of both drugs was good. None of the patients had to discontinue treatment because of an adverse event. Two patients treated with cyclosporin showed increased plasma levels of creatinine. CONCLUSIONS: Cyclosporin is more effective, fast, and predictable in its effect than mycophenolate mofetil to control moderate-to-severe chronic plaque psoriasis. Both drugs are well tolerated in short courses of treatment. 相似文献
40.
A precise and simple method for the determination of (234)Th activity by Cerenkov counting is described. A calibrated natural uranium solution (having (234m)Pa and (238)U in secular equilibrium) in 0.1M HNO(3) is used to construct the calibration curve. Because (231)Th (a beta-emitting nuclide present in the decay chain of (235)U) contribution to Cerenkov counting is experimentally proved to be negligible only in the case of low enriched uranium samples, simple calculations are needed to accomplish the activity determination. 相似文献