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61.
AIM: To assess the ability of sickle cells to interfere with the release or transfer of endothelium-derived relaxing factor (EDRF) in comparison to normal erythrocytes. METHODS: A perfusion-superfusion bioassay system was used a canine carotid artery with endothelium (donor of EDRF) and a ring of the same vessel without endothelium (detector) were separated by tubing resulting in a five second interval for transfer of EDRF from donor to detector. Changes in isometric tension were monitored in both the donor and the detector preparations. Release of EDRF, as determined by sustained relaxations during the contractions to phenylephrine, was induced by infusing acetylcho-line through the donor artery. RESULTS: Supervision with normal and sickle erythrocytes caused impairment of the endothelium-dependent relaxations in both detector and donor tissues. When infused through the transfer line, sickle cells were less potent than normal erythrocytes in inhibiting relaxation in the detector tissues. In contrast, i 相似文献
62.
63.
Yvone VicenteCecilia Rocha Jiakang YuGuillermo Hernandez-Peredo Leopoldo MartinezBelen Perez-Mies Juan A. Tovar 《Journal of pediatric surgery》2002,37(1):40-46
Background/Purpose: The lower esophageal sphincter and the diaphragmatic crural sling form the gastroesophageal barrier. This work shows that division of the sphincteric component alone suffices to induce reflux esophagitis in piglets. Methods: Male piglets underwent either sham operation (n = 7) or extramucosal myotomy of the gastroesophageal junction (n = 8). Before and 1 week after the operation, pull-through manometry was performed under sedation. Pressures taken on the 4 quadrants at 20 1-mm intervals on both time endpoints were compared by pairwise Wilcoxon tests. The distal esophagus was studied histologically after 8 weeks. Results: The pressure profiles did not change after sham operation. In contrast, they were significantly flattened in the distal half of the high-pressure zone after myotomy reflecting disappearance of the sphincteric component of the barrier. Esophagitis was seen in all myotomized piglets but in none from the sham group. Conclusions: Lower esophageal sphincter myotomy alone with preservation of the crural sling induces reflux esophagitis in piglets. This animal, widely available and not too costly, is an excellent model for gastroesophageal research. 相似文献
64.
Management of odontoid fractures using anterior screw fixation: analysis of 15 cases 总被引:8,自引:0,他引:8
Dantas FL Prandini MN Caires AC Fonseca GA Raso JL 《Arquivos de neuro-psiquiatria》2002,60(3-B):823-829
A retrospective analysis of the results of 15 patients with odontoid fractures type II P and II N, according to Roy-Camille's classification is presented. They were operated on by an anterior approach and direct fixation of the odontoid process through a screw. There were 13 men and 2 women, the age ranging from 14 to 74 years. The follow up period was from 6 to 36 months (mean 20 months). There was only one complication related to the surgical technique: one screw was misplaced and it was necessary another surgery to replace it. There were no deaths in this series. There were no screw breakdown and the fusion rate was 94%. We propose, based on this study, that the classification of Roy-Camille for odontoid fractures should be always used, since it proposes one surgical approach for each type of fracture. The results of this series show that this technique is useful and has advantages over another modalities of treatment. The correct diagnosis of the type of fracture and an appropriate selection of patients are the main elements to achieve good results. 相似文献
65.
OBJECTIVE : To determine the extent to which mineralocortioid hypertension depends on a direct action of aldosterone on the kidney or on the brain. METHODS : Studies were performed in conscious sheep that were previously uninephrectomized, implanted with silastic cannulae in the renal artery of the remaining kidney, and had guide tubes implanted over the lateral cerebral ventricles. The effect of aldosterone, infused either intrarenally (i.r.; 2 microg/h) or intravenously (i.v.; 2 and 10 microg/h) for 10 days (n = 5), on arterial pressure and fluid and electrolyte balance was determined. The i.r. (2 microg/h) and i.v. (10 microg/h) doses were calculated to give similar intrarenal concentrations of aldosterone. In a further study, the effect of intracerebroventricular (i.c.v.) infusion of aldosterone (2 microg/h for 21 days) on arterial pressure was examined (n = 5). RESULTS : Infusion of aldosterone caused a progressive increase in mean arterial pressure from 83 +/- 3 mmHg to a maximum of 100 +/- 4 mmHg (P < 0.001) with 2 microg/h i.r. and from 84 +/- 3 mmHg to a maximum of 104 +/- 4 mmHg (P < 0.001) with 10 microg/h i.v., both by day 7. With both infusions there were similar increases in plasma [Na+] and decreases in plasma [K+] and total protein concentration (P < 0.05) between days 3 and 5; these were maintained throughout the infusion. There were no significant changes with i.v. aldosterone (2 microg/h). Long-term i.c.v. infusion of aldosterone (2 microg/h for 21 days) caused no change in arterial pressure. CONCLUSIONS : In conscious sheep the hypertensive response to aldosterone resulted from an action on the kidney, with no evidence for a direct action on the brain. 相似文献
66.
Pérez de Isla L García Fernández MA Moreno M Bermejo J Moreno R López de Sá E López Sendón JL Jiménez Candil J Díaz Castro O 《Revista espa?ola de cardiología》2002,55(11):1132-1136
INTRODUCTION AND OBJECTIVES: The usefulness and safety of transesophageal echocardiography have been assessed in other studies but there is no report in which these factors have been evaluated in the acute phase of myocardial infarction.Patients and method. Transesophageal echocardiography was performed 56 times in 55 patients in the first week after a myocardial infarction. RESULTS: The study was completed in 54 of 56 patients. The indications were a transthoracic acoustic window that did not provide an accurate diagnosis in 13 (23.2%), diagnosis of mechanical complications and severity assessment of mitral regurgitation in 35 (62.5%), exclusion of aortic dissection in 4 (7.1%), assessment of the severity of aortic stenosis in 1 (1.8%), exclusion of the presence of atrial thrombus in 1 (1.8%), evaluation of the left ventricular outflow tract gradient in 1 (1.8%), and evaluation of the presence of a left ventricular thrombus in 1 patient (1.8%). Two patients (3.6%) died while the study was being made, the first one 10 minutes after finishing the echocardiogram due to progression of a partial rupture of the papillary muscle and the second due to left ventricle free wall rupture. In both patients, the indication for transesophageal echography was the need for proper evaluation of a post-Acute Myocardial Infarction mechanical complication. CONCLUSIONS: Transesophageal echocardiography is a very useful technique for evaluating patients during the acute phase of myocardial infarction but further studies are needed to establish its safety in these patients. 相似文献
67.
Chatenoud L Mosconi P Malvezzi M Colombo P La Vecchia C Apolone G 《Preventive medicine》2005,41(1):328-333
BACKGROUND: Measuring self-perceived health status and risk perception according to environmental factors remains a major open issue with important health policy implications. METHODS: To measure self-perceived health status in an area where a major thermoelectric plant has been active since 1994, in October 2001, we conducted a two sample survey using the SF-12 Health Survey. The study sample (2001 individuals) representative of the population living in the plant area (Montalto di Castro, Central Italy) was compared with a random sample of the general Italian population (1928 individuals). Mean values were adjusted for age, sex and education. RESULTS: SF-12 summary scales means are comparable in both samples: 50.2 (SE: 0.3) versus 49.9 (SE: 0.3) for the physical score, and 47.7 (SE: 0.4) versus 48.7 (SE: 0.4) for the mental score for Montalto di Castro area and Italian sample respectively. CONCLUSION: People living near a major thermoelectric plant have a subjective health status comparable to that reported by the general Italian population. 相似文献
68.
Background/Aim
Nitrofen induces heart hypoplasia together with congenital diaphragmatic hernia (CDH) in rats. Intracellular oxidative stress might be one of the mechanisms of action of the teratogen, and vitamin A has been shown to reverse in part these effects when administered simultaneously or shortly after it. This study aims at testing the hypothesis that vitamin A and other antioxidant vitamins, such as E and C, could improve myocardial development even when administered late in gestation, a likely useful period for prenatal medication.Material and Methods
Time-mated Sprague-Dawley female rats were exposed to either vehicle (control) or 100 mg of nitrofen (experimental) on day 9.5 of gestation. In 3 additional groups, the animals were exposed to vitamin A (total 15 000 IU), vitamin E (total 150 IU), or vitamin C (total 150 IU) on days 16, 17, and 18. The fetuses were recovered on day 21, and randomly selected hearts of those with CDH were processed for histologic studies (hematoxylin-eosin and periodic acid-Schiff stainings), DNA and protein contents, and ki-67 (proliferation) and terminal deoxynucleotidyl transferase-mediated dUTP-biotin end labeling (apoptosis) studies. The differences among groups were assessed by analysis of variance with Bonferroni/Dunn post hoc tests and a threshold of significance of P < .05.Results
Nitrofen induced heart hypoplasia in terms of decreased heart/body weight, cell mass (less DNA and protein), and proportion of proliferating cells with increased apoptosis. Vitamin C alleviated weight hypoplasia and the 3 vitamins were able to restore cell mass and to reestablish near-normal figures of proliferation and apoptosis.Conclusions
Antioxidant vitamins A, E, and C given late in gestation alleviate heart hypoplasia that accompanies CDH in the rat model. This timing suggests that the beneficial effects are exerted on the maturational phase of development. 相似文献69.
70.
Colorectal cancer metastases rarely develop outside liver, lungs and lymph nodes, and only exceptionally in skeletal muscle. The very low incidence of such metastasis sites may be due either to underestimation of the problem or to their intrinsic rarity. We report a case of metastasis from colorectal cancer that developed in the left calf and manifested itself as a painful non-fluctuating mass. The relevant literature is also reviewed. 相似文献