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排序方式: 共有5542条查询结果,搜索用时 15 毫秒
1.
Massimo Porena Sauro Biscotto Elisabetta Costantini Ettore Mearini Livio Verdini 《Neurourology and urodynamics》2003,22(3):206-222
AIMS: The aim of this study is to compare PUMA curves with different pathologic conditions causing bladder dysfunction in 158 men and 83 women. METHODS: PUMA results in terms of bladder outlet obstruction and detrusor contractility were compared in 92 men with benign prostatic hypertrophy (BPH) and p(ves) congruent with p(det) (i.e., p(abd) congruent with 0) with the results of the urodynamics operator's opinion, the provisional International Continence Society method, Abrams and Griffith's diagram, urethral resistence factor (URA), Sch?fer's diagram, and Watt factor. PUMA curves correlated reliably with different pathologic conditions such as obstructive BPH, orthotopic bladder, cystocele, the neurological bladder, and bladder diverticulum. Statistical analysis indicated excellent agreement between PUMA and URA; agreement with other methods was good in cases of obstruction and nonobstruction. In doubtful cases, as diagnosed by standard methods, PUMA agreed only with the Abrams and Griffith's diagram. PUMA and Wmax were in good agreement on detrusor con traction force. Agreement between PUMA and Sch?fer's diagram was excellent for patients with detrusor hypercontractility and good for patients with detrusor hypocontractility and normocontractility. PUMA is the only method applicable to women. It is easy to perform. When integrated with other diagnostic tests, it provides realistic data for diagnosis, medical or surgical therapy, and outcome. 相似文献
2.
Vigilio Ballabeni Massimiliano Tognolini Simona Bertoni Renato Bruni Alessandra Guerrini Gabriela Moreno Rueda Elisabetta Barocelli 《Pharmacological research》2007,55(1):23-30
Ocotea quixos essential oil was shown to possess significant inhibitory activity of platelet aggregation and clot retraction in rodent plasma. This study is aimed at fully characterizing the antiplatelet activity of the whole essential oil and its main components trans-cinnamaldehyde and methyl cinnamate also in human plasma, at investigating the mechanism underlying such activity and at evaluating the potential antithrombotic activity of subacute treatment of mice with Ocotea essential oil. In vitro Ocotea essential oil and trans-cinnamaldehyde inhibited arachidonic acid-, U46619-, ADP-, phorbol12-myristate13-alcetate-, collagen-induced platelet aggregation and thrombin-induced clot retraction in human and rodent plasma; Ocotea oil and trans-cinnamaldehyde competitively antagonized contractions induced by thromboxane A2 receptor agonist U46619 in rat isolated aortic ring (K(B) = 18 and 3.2 microg ml(-1), respectively). In vivo Ocotea oil, orally administered in a subacute treatment (30-100 mg kg(-1) day(-1) for 5 days) to mice, prevented acute thrombosis induced by collagen-epinephrine intravenous injection. This antithrombotic activity was not accompanied by pro-haemorragic side effect, as detected by the inactivity in bleeding test, thus showing a favourable safety profile compared to the conventional antiplatelet agent, acetylsalicylic acid. Present findings indicate that Ocotea essential oil possesses potent and safe antithrombotic activity attributable to its antiplatelet and vasorelaxant effects. The main constituent trans-cinnamaldehyde seems to be the primary responsible for this activity through a putative mechanism involving the inhibition of thromboxane A2 receptors. 相似文献
3.
Defenses of the hamster lung against human neutrophil and porcine pancreatic elastase 总被引:2,自引:0,他引:2
P J Stone E C Lucey J D Calore M P McMahon G L Snider C Franzblau 《Respiration; international review of thoracic diseases》1988,54(1):1-15
Instillation of human neutrophil elastase (HNE) into hamster lungs produces milder emphysema but more pulmonary hemorrhage than an equivalent amount of porcine pancreatic elastase (PPE), whether equivalence is determined by elastolytic units or moles. We undertook a study of the mechanisms of these differences. 125I-HNE or 3H-PPE were instilled intratracheally into hamsters. The partitioning of radioactivity between bronchoalveolar lavage fluid (BAL) and lung tissue was similar for HNE and PPE as were the half-lives, 45 and 51 min, respectively, for uncomplexed, enzymatically active HNE and PPE. In BAL there was preferential binding and inactivation of HNE by the hamsters' alpha-1-protease inhibitor (a-1-PI) whereas PPE was preferentially bound by alpha-2-macroglobulin (a-2-M). This was also observed in vitro when HNE and PPE were incubated with plasma from untreated hamsters. Nevertheless, when the sum of the elastase binding capacity of a-1-PI and a-2-M was considered, hamster plasma had similar binding capacities for HNE and PPE. It is known that the enzymatic activity of elastases is inhibited by formation of a stable complex with a-1-PI. On the other hand, elastases bound to a-2-M are protected against a-1-PI inhibition but can free themselves by proteolysis and exhibit elastolytic activity. Preferential inactivation of HNE by a-1-PI may be one mechanism that accounts for the lesser emphysema-inducing potency of HNE than of PPE. 相似文献
4.
Silvia Miano Oliviero Bruni Vincenzo Leuzzi Maurizio Elia Elisabetta Verrillo Raffaele Ferri 《Clinical neurophysiology》2004,115(4):938-945
OBJECTIVE: Sleep disturbances are frequent in Angelman syndrome (AS); however, beside the few studies which have investigated sleep disorders in AS by means of questionnaires, to our knowledge, no systematic polysomnographic recordings have been carried out in AS patients. The present study represents the first attempt to study sleep patterns of AS by polysomnography, to evaluate the influences of sleep on the paroxysmal electroencephalogram (EEG) patterns of AS and to assess the eventual age-related changes of sleep architecture and of sleep EEG abnormalities in children and adolescents with AS. METHODS: Fifteen children with AS (7 males and 8 females, mean age 7.2 years, range 3-16 years), attending the Sleep Center of the Department of Child Neurology and Psychiatry of the University of Rome 'La Sapienza' and the Sleep Research Centre of the Oasi Institute (IRCCS) of Troina were included and subdivided into two subgroups by age: subgroup 1, aged 3-5 years, and subgroup 2, aged 9-17 years. Two control groups of age-matched normal subjects were also included: one aged less than 8 years and another aged more than 8 years; additionally, two other groups of age-matched children with epilepsy and mental retardation of different origin, one aged less and one aged more than 9 years were taken into consideration. The statistical comparison between the sleep parameters obtained from the patients and those from the other groups was carried out by means of the non-parametric Kruskal-Wallis ANOVA and the Mann-Whitney U test. RESULTS: The most frequent EEG abnormality found in AS patients appeared to be the 2-3 c/s poorly defined spike/waves complexes. This pattern was influenced by sleep stages; the duration of the runs showed an increasing length with sleep deepening from sleep stage 1 to slow-wave sleep (SWS). Moreover, the 2-3 c/s bursts activity present in sleep stage 2 showed a slowing to 1-2 c/s during SWS. Regarding sleep architecture, in subjects with AS aged <8 year there was a significant reduction in sleep efficiency as compared to normal controls, while the percentage and duration of REM sleep was significantly lower and the percentage of SWS was significantly higher. REM sleep time was reduced in AS subjects aged >8 years than in normal controls. The comparison between AS groups and mental retardation with epilepsy groups did not show significant differences. CONCLUSIONS: Similarly to other types of genetically determined mental retardation syndromes, also subjects with AS seems to show important abnormalities of their sleep polysomnographic patterns. SIGNIFICANCE: This is the first study which reports, in detail, these abnormalities and opens a new path for further insight into the knowledge of additional sleep-related disturbances which are reported in sleep questionnaires by the caregivers of AS subjects. 相似文献
5.
6.
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
7.
8.
Heterogeneity of human bone 总被引:2,自引:0,他引:2
J T Ninomiya R P Tracy J D Calore M A Gendreau R J Kelm K G Mann 《Journal of bone and mineral research》1990,5(9):933-938
Matched samples of bone from the lumbar spine and tibia were obtained at autopsy from three adult males who had no known evidence of metabolic bone disease at the time of their demise. The soluble noncollagenous bone proteins were quantitatively extracted from these samples and assayed for the relative content of two bone-associated proteins, osteocalcin and osteonectin. When compared to trabecular bone, cortical bone had higher levels of osteocalcin and much lower levels of osteonectin. When concentration is expressed per gram of dried bone, the osteocalcin excess in cortical bone ranged from 30- to 32-fold, and the osteonectin excess in trabecular bone ranged from 21- to 47-fold. These differences were significant (P less than 0.01) using analysis of variance. We conclude that the human skeleton is not homogeneous with regard to these biochemical markers and that cortical and trabecular bone are biochemically quite distinct. This implies that these two types of bone may be subject to distinct regulatory mechanisms and that global assessments of skeletal function and bone quality based upon soluble markers should be applied with caution. The data also imply that a differential assessment of skeletal performance may be possible using biochemical serum markers. 相似文献
9.
Bartolo Zingone Elisabetta Rauber Giuseppe Gatti Aniello Pappalardo Bernardo Benussi Gabriella Forti Umberto Tognolli Marco Gabrielli 《European journal of cardio-thoracic surgery》2007,31(6):990-997
Objective: Severe atherosclerosis of the ascending aorta and arch frequently causes difficulties during heart operations, hindering surgical manoeuvres and potentially leading to systemic embolism. The aim of our study was to assess the safety and effectiveness of replacing the atherosclerotic ascending aorta in this setting. Methods: Aortic atherosclerosis was characterized by epiaortic ultrasonographic scanning in 90.1% of 1927 consecutive adult patients undergoing cardiac operations, and by computed tomographic chest scanning in selected cases. Thirty-six of the 152 patients requiring major derangements from our standard practice due to aortic atherosclerosis underwent replacement of the ascending aorta and constitute the study group. Replacement of the aorta was extended to the arch in 13 cases (36.1%). It was associated with single or multiple valve surgery in 34 patients (94.4%) and with coronary revascularization in 30 (83.3%). Two patients (5.6%) underwent coronary bypass grafting without valve surgery. A cryoablation procedure was associated in three patients with permanent atrial fibrillation. Deep hypothermic circulatory arrest was employed in 34 patients (94.4%), while proximal aortic disease allowed conventional distal crossclamping in 2 cases. The risk of operative mortality was estimated by the logistic EuroSCORE both with and withholding the variable ‘surgery of the thoracic aorta’. All survivors were followed-up for 1–41 months (16 ± 12). Results: Two patients died in the hospital (5.6%) and two during follow-up, for a cumulative survival of 91.3% and 85.6% at 1 and 3 years, respectively (hospital deaths included). The hospital death rate compared favourably with the expected estimates of 25.5% (p < 0.05) and 10.3% (p = 0.67) obtained by the EuroSCORE full model and without ‘aortic surgery’, respectively. In-hospital adverse neurologic events occurred in six patients (16.7%), including stroke in one patient (2.8%) and neurocognitive disturbances in five (13.9%), although they were all transient and cleared before discharge. Excess bleeding required re-exploration in four patients (11.1%), and one more patient underwent emergency grafting for acute postoperative coronary occlusion. Ten patients (38.5%) were intubated for longer than 24 h. Conclusion: Despite significant perioperative morbidity, replacement of the severely atherosclerotic aorta is worth consideration to avert expectedly higher death and stroke rates. 相似文献
10.
Carlo Piccinni Chiara Sacripanti Elisabetta Poluzzi Domenico Motola Lara Magro Ugo Moretti Anita Conforti Nicola Montanaro 《European journal of clinical pharmacology》2010,66(2):199-206