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91.
Maria P. Panozzo Carlo Fabris Daniela Basso Giuseppe Del Favero Aldo Infantino Attilio Cecchetto Mario Plebani Remo Naccarato 《Clinical and experimental pharmacology & physiology》1993,20(3):185-191
1. The authors investigated the effect of two extrahepatic cholestasis models (one by bile duct ligation and the other by choledocho-jugular fistula) on the hepatic clearance of horseradish peroxidase in male Sprague-Dawley rats divided into four groups. 2. In groups A (n = 5 rats) and B (n = 5), bile duct ligation was performed, while a choledocho-jugular fistula was created in groups C (n = 5) and D (n= 7). A 10 mg intravenous bolus of horseradish peroxidase was injected after 24 h (groups A and C), 48 h (groups B and D) or 1 h (Group E; five sham-operated rats). Serum and bile samples were then serially collected for 2 h. 3. In all groups, serum horseradish peroxidase levels increased soon after injection and then rapidly decreased, the curves being similar. Biliary excretion increased for 30 min and then slowly decreased. The highest horseradish peroxidase biliary concentrations and outputs were found in Group B followed by Group A; both groups had significantly higher levels than Group E. No difference was found between horseradish peroxidase biliary excretion of groups C and D and that of sham-operated rats. 4. When each group was considered separately, sampling times correlated with the corresponding ratios of bile/ plasma HRP. Significant differences were found between the relative slopes of groups A, B and E, but not between those of groups C, D and E. 5. In conclusion, bile duct obstruction greatly affects the plasma-bile transfer of fluid phase markers, such as horseradish peroxidase, while single retention, caused by choledocho-jugular fistula, has no influence. The increased biliary hyperpressure related to the duration of cholestasis may account for the degree of horseradish peroxidase transfer which, in turn, probably depends on an enhanced paracellular passage. 相似文献
92.
Twenty-four patients treated with 150 mg amitriptyline per day for an episode of major depression underwent a standardized heart rate analysis (HRA) before therapy and after 14 days. The battery of cardiovascular reflex tests included the determination of the coefficient of variation (CV) while resting and during deep respiration, a spectral analysis of heart rate, the heart rate response to standing, and the Valsalva manoeuvre. The results of the initial HRA did not differ from a group of 24 normal control subjects matched for age and sex. On day 14 of treatment the patients showed significantly reduced values of heart rate variability in all tests (P<0.0001), probably due to the anticholinergic side effects of amitriptyline. Heart rate increased form 78.1 to 93.6 bpm on average (P<0.0001). Abnormal CV at rest was registered in 96% of the patients; during deep respiration 29% showed abnormal CV results. An abnormal spectral analysis was found in 100% of the cases (low frequency peak: 42%, mid-frequency peak: 100%, high frequency peak: 79%). The heart rate response to standing was abnormal in 75% and the Valsalva test in 33% of the cases. Eighty-eight percent of the patients fulfilled the criteria of a cardiovascular autonomic neuropathy under the conditions of amitriptyline therapy. As yet, the consequences of these changes for the patients have not been sufficiently elucidated. 相似文献
93.
In human Y-79 retinoblastoma cells corticotropin-releasing hormone (CRH) produces a marked and rapid increase of adenylate cyclase activity. The concentration of the peptide producing half-maximal stimulation is 60 nM. The effect of CRH is significantly antagonized by the specific CRH receptor antagonist alpha-helical CHR 9-41 and is mimicked by sauvagine and urotensin I, two peptides displaying sequence homology with CRH. These results demonstrate the presence of functional CRH receptors in human Y-79 retinoblastoma cells and suggest that this cell line may be a suitable model in which to study the action of CRH on human retinal cell function. 相似文献
94.
Anya Pimentel Gomes Fernandes Vieira Jose Maria Sampaio Meneses Jr Renato Luiz Maia 《Journal of oral pathology & medicine》2007,36(2):117-119
Cementoblastomas are benign lesions of the odontogenic ectomesenchyme that rarely occur related to the primary dentition, especially on the left side of the mandible. This study describes a case of a true cementoblastoma related to the left second primary mandibular molar in a 7-year-old child (the largest one seen in the left side of the mandible). Additionally, the radiographic and histologic findings of the lesion are described in details. 相似文献
95.
Andrea von Berg Renate Engelstätter Predrag Minic Miodrag Sréckovic Maria Luz Garcia Garcia Tadeusz Lato Jan H. Vermeulen Stefan Leichtl Stefan Hellbardt Thomas D. Bethke 《Pediatric allergy and immunology》2007,18(5):391-400
Ciclesonide is an onsite-activated inhaled corticosteroid (ICS) for the treatment of asthma. This study compared the efficacy, safety and effect on quality of life (QOL) of ciclesonide 160 microg (ex-actuator; nominal dose 200 microg) vs. budesonide 400 microg (nominal dose) in children with asthma. Six hundred and twenty-one children (aged 6-11 yr) with asthma were randomized to receive ciclesonide 160 microg (ex-actuator) once daily (via hydrofluoroalkane metered-dose inhaler and AeroChamber Plus spacer) or budesonide 400 microg once daily (via Turbohaler) both given in the evening for 12 wk. The primary efficacy end-point was change in forced expiratory volume in 1 s (FEV1). Additional measurements included change in daily peak expiratory flow (PEF), change in asthma symptom score sum, change in use of rescue medication, paediatric and caregiver asthma QOL questionnaire [PAQLQ(S) and PACQLQ, respectively] scores, change in body height assessed by stadiometry, change in 24-h urinary cortisol adjusted for creatinine and adverse events. Both ciclesonide and budesonide increased FEV1, morning PEF and PAQLQ(S) and PACQLQ scores, and improved asthma symptom score sums and the need for rescue medication after 12 wk vs. baseline. The non-inferiority of ciclesonide vs. budesonide was demonstrated for the change in FEV1 (95% confidence interval: -75, 10 ml, p = 0.0009, one-sided non-inferiority, per-protocol). In addition, ciclesonide and budesonide showed similar efficacy in improving asthma symptoms, morning PEF, use of rescue medication and QOL. Ciclesonide was superior to budesonide with regard to increases in body height (p = 0.003, two-sided). The effect on the hypothalamic-pituitary-adrenal axis was significantly different in favor of ciclesonide treatment (p < 0.001, one-sided). Both ciclesonide and budesonide were well tolerated. Ciclesonide 160 microg once daily and budesonide 400 microg once daily were effective in children with asthma. In addition, in children treated with ciclesonide there was significantly less reduction in body height and suppression of 24-h urinary cortisol excretion compared with children treated with budesonide after 12 wk. 相似文献
96.
Amy C Y Lo Alvin K H Cheung Victor K L Hung Chung-Man Yeung Qing-Yu He Jen-Fu Chiu Stephen S M Chung Sookja K Chung 《Journal of cerebral blood flow and metabolism》2007,27(8):1496-1509
Previously, we reported that transgenic mice overexpressing endothelin-1 in astrocytes showed more severe neurological deficits and increased infarct after transient focal ischemia. In those studies, we also observed increased level of aldose reductase (AR), the first and rate-limiting enzyme of the polyol pathway, which has been implicated in osmotic and oxidative stress. To further understand the involvement of the polyol pathway, the mice with deletion of enzymes in the polyol pathway, AR, and sorbitol dehydrogenase (SD), which is the second enzyme in this pathway, were challenged with similar cerebral ischemic injury. Deletion of AR-protected animals from severe neurological deficits and large infarct, whereas similar protection was not observed in mice with SD deficiency. Most interestingly, AR(-/-) brains showed lowered expression of transferrin and transferrin receptor with less iron deposition and nitrotyrosine accumulation. The protection against oxidative stress in AR(-/-) brain was also associated with less poly(adenosine diphosphate-ribose) polymerase (PARP) and caspase-3 activation. Pharmacological inhibition of AR by Fidarestat also protected animals against cerebral ischemic injury. These findings are the first to show that AR contributes to iron- and transferrin-related oxidative stress associated with cerebral ischemic injury, suggesting that inhibition of AR but not SD may have therapeutic potential against cerebral ischemic injury. 相似文献
97.
Gabriel Mircescu Dimitrie Capsa Maria Covic Mirela Gherman Caprioara Gheorghe Gluhovschi Ovidiu Golea Nicolae Ursea Liliana Garneata Vasile Cepoi Nicolae Constantinovici Adrian Covic 《Nephrology, dialysis, transplantation》2004,19(12):2971-2980
INTRODUCTION. This report describes the current status of nephrology and renal replacement therapy (RRT) in Romania, a country with previously limited facilities, highlighting national changes in the European context. METHODS: Trends in RRT development were analysed in 2003, on a national basis, using the same questionnaires as in previous surveys (1991, 1995). Survival data and prognostic risk factors were calculated retrospectively from a large representative sample of 2284 patients starting RRT between January 1, 1995 and December 31, 2001 (44% of the total RRT population investigated). RESULTS: In 2003, RRT incidence [128 per million population (p.m.p.)] and prevalence (250 p.m.p.) were six and five times higher, respectively, than in 1995. The annual rate of increase in the stock of RRT patients (11%) was supported mainly by an exponential development of the continuous ambulatory peritoneal dialysis (CAPD) population (+600%), while the haemodialysis (HD) growth rate was stable (+33%) and renal transplantation made a marginal contribution. Renal care infrastructure followed the same trend: nephrology departments (+100%) and nephrologists (+205%). The characteristics of RRT incident patients changed accordingly to current European epidemiology (increasing age and prevalence of diabetes and nephroangiosclerosis). The estimated overall survival of RRT patients in Romania was 90.6% at 1 year [confidence interval (CI) 89.4-91.8] and 62.2% at 5 years (CI 59.4-65.0). Patients' survival was negatively influenced (Cox regression analysis) by age >65 years (P < 0.001), lack of pre-dialysis monitoring by a nephrologist [P = 0.01, hazards ratio (HR) = 0.8], severe anaemia, lack of erythropoetin treatment (P < 0.001, HR = 0.6), and co-morbidity, e.g. cardiovascular diseases (P < 0.001, HR = 1.8) and diabetes mellitus (P < 0.001, HR = 2.2). CONCLUSIONS: Although the rate of increase in RRT patient stock in 1996-2003 in Romania was the highest in Europe, the prevalence remained below the European mean. As CAPD had the greatest expansion, followed by HD, an effective transplantation programme must be set up to overcome the imbalance. The quality of RRT appears to be good and survival was similar to that in other registries. Further evolution implies strategies of prevention, based on national surveys, supported by the Romanian Renal Registry. 相似文献
98.
António Travassos Susana Teixeira Pinto Ferreira Isaura Regadas Ana Sofia Travassos Florindo Esteves Esperancinha Isabel Prieto Grapa Pires Robert van Velze A Valido Maria do Céu Machado 《Ophthalmic surgery, lasers & imaging》2007,38(3):233-237
The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months 相似文献
99.
Margaret M Plack Maryanne Driscoll Maria Marquez Lynn Cuppernull Joyce Maring Larrie Greenberg 《Ambulatory Pediatrics》2007,7(4):285-291
OBJECTIVE: Reflection enables learners to analyze their experiences and capture the wisdom that lies within. Effective teaching requires reliable methods of assessment. Several methods of assessing reflective writing have been described; however, they often require significant training, and reliability has seldom been assessed. This study was designed to determine the interrater reliability of a method of assessing reflective writing by using a modified Bloom's Taxonomy. METHODS: Twenty-one third-year medical students maintained reflective journals throughout their pediatric clerkship. A coding schema based on Bloom's Taxonomy was developed to assess the level of cognitive processing evident in the journals. Journals were independently assessed by 3 raters. Percent agreement, kappa statistics, and intraclass correlation coefficients (ICC [2,1]) were used to assess interrater reliability. RESULTS: Three hundred eight entries from 21 journals were assessed. Percent agreement ranged from 78.2% to 100%. Kappa statistic for each level ranged from 0.57 +/- 0.04 to 0.73 +/- 0.04, and for the highest level of processing evident it ranged from 0.52 +/- .04 to 0.58 +/- 0.04. ICC (2,1) for each level of cognitive processing ranged from 0.62 (F = 6.20; P = .000) to 1.00, and for the highest level of cognitive processing evident, it was 0.79 (F = 12.42; P = .000). Substantial to almost perfect agreement was attained. CONCLUSIONS: Reflective journals allow learners to revisit their experiences for critical analysis and deeper learning. This study describes a reliable method, based on Bloom's Taxonomy, of determining whether learners have achieved higher order thinking through reflective journal writing. This method can provide a baseline for facilitating higher order processing, critical thinking, and reflective practice. 相似文献
100.
The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain. 相似文献