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71.
In acute cardiac rejection, left ventricular diastolic function is altered. To study these abnormalities and their utility in cardiac allograft rejection, we studied 56 cardiac transplant recipients. All patients were assessed with endomyocardial biopsy and Doppler echocardiography done in the same day. A total of 163 Doppler studies were recollected. Cardiac transplant recipients were excluded during the early 6 weeks postoperative period. Totally, 100 biopsies were normal, 48 positive for mild rejection (Billingham Gde I-II) and 15 positive for moderate or severe rejection (Billingham Gde III-IV). Compared to negative biopsies, during acute rejection left ventricular wald thickness significantly increased (p < 0.05); isovolumic relaxation period and pressure half-time significantly decreased (p < 0.05, p < 0.001 respectively). Nevertheless, increase in peak early mitral flow velocity was only significantly associated with severe rejection (p < 0.001). Correlating only progressive shortening of isovolumic relaxation period parameter in the diagnosis of graft rejection, we forward a high sensibility (85%) and low specificity (57%). Thus, Doppler echocardiographic evaluation of left ventricular diastolic function provides a non-invasive tool for early detection of acute rejection monitoring after the early postoperative period.  相似文献   
72.
The objective of the study was to describe the implementation of measures for preventing tobacco consumption developed in the Catalan Network of Smoke-free Hospitals. Information from 25 hospitals that are actively involved in the Catalan Network of Smoke-free Hospitals (April 2004) was used. The degree of implementation of the Smoke-free Hospitals Project was analysed by means of the Self-Audit Questionnaire of the European Network for Smoke-free Hospitals; each hospital was analysed globally and according to the duration of its Network membership (<1 year: implementation stage; > or =1 year: consolidation stage). In terms of global indicators, there were high levels of commitment (64.8%), communication (74.7%), tobacco control (77.4%) and implementation of smoke-free environments (81.0%). A lower degree of implementation (<50%) was found in education and training, health promotion and healthy workplaces. According to the duration of Network membership, significant differences were observed for communication, environment, healthy workplaces and follow-up. Deficits were observed in areas such as specialist training and cessation support, and further input is required here. By identifying areas needing attention, providing a guide for policy development and by administering it periodically, one can ensure that progress is kept on track.  相似文献   
73.
The distribution of neuropeptide Y (NPY)-like immunoreactivity was studied in the brain of the lizard Gallotia galloti, in order to gain insight into the comparative topography of this peptide. Antisera against both NPY and its C-terminal flanking peptide (C-PON) were used, demonstrating a general coexistence of both peptides, as described in other vertebrates. Most NPY-like immunoreactive (NPY-LI) cell bodies were observed in the telencephalon, specifically in various olfactory structures, all cortices, septum, basal ganglia (except for the globus pallidus), the nucleus of the diagonal band of Broca, the amygdaloid complex, and the bed nucleus of the anterior commissure. NPY-LI cells were also seen in the preoptic and hypothalamic regions and the dorsal thalamus (mainly in the perirotundal belt), as well as in the mesencephalic tegmentum (in the ventral tegmental area, the substantia nigra, and the retrorubral area). NPY-LI fibers and terminals were widely distributed in the brain. All visual and auditory neuropiles were densely innervated. Specially dense plexuses were seen in the nucleus accumbens, the ventral pallidum, the suprachiasmatic and ventromedial hypothalamic nuclei, the nucleus medialis thalami, the left habenula, and the central nucleus of the torus semicircularis. Our analysis shows that the distribution of NPY-like immunoreactivity in the forebrain of Gallotia largely resembles that of other vertebrates, whereas differences are mainly observed in the brainstem. The widespread distribution of NPY in the lizard brain suggests several modulatory functional roles, either in local-circuit systems of the forebrain, or in various limbic, neuroendocrine, and sensory pathways.  相似文献   
74.
75.
The efficacy of the new nonsedating antihistamines loratadine and cetirizine was compared in a randomized, single-blind, crossover, controlled study with that of the classical antihistamines cyproheptadine and ketotifen in seven patients with primary acquired cold urticaria (ACU). The patients received each of the four drugs for 14 consecutive days with a 7-day interval between drugs. We evaluated clinical symptomatology, adverse effects, minimum time of cold contact stimulation required to induce an immediate coalescent wheal (CSTT), and inhibition of histamine-induced wheal response. Both loratadine and cetirizine showed suppression of symptoms with infrequent adverse effects. Important side-effects were observed in patients receiving cyproheptadine. Improvement in CSTT was statistically significant for all drugs compared with baseline values, without differences among them. The histamine-induced skin test was significantly inhibited by all antihistamines. Wheal reductions were 34.6% for loratadine and 50.9% for cetirizine. This study suggests that both loratadine and cetirizine may be effective in the treatment of primary ACU.  相似文献   
76.
Two new cases of prostatic blue nevus are studied with routine histological, immunohistochemical and ultrastructural methods. Both cases showed a chronic lower urinary tract obstruction due to a benign prostatic hyperplasia with spindle-shaped stromal cells loaded with melanin pigment. These cells were positive for S-100 and negative for HMB-45 antibodies, being, to the best of our knowledge, the first time that this antibody has been tested in prostatic pigmented lesions. The electron-microscopy study was performed in the first case, confirming the nature of these pigmented cells as melanocytes derived from the neural crest showing melanosomes in all the stages of differentiation and without complete basal cell membrane. The histogenesis of pigmented lesions of the prostate and the differences between blue nevus and melanosis are discussed, and the literature is reviewed.  相似文献   
77.
A 32-year old woman, with endocarditis caused by Streptococcus mitis, and systolic murmur is presented. The Doppler examination was found a systolic gradient of 150 mmHg. Aortography showed a multiple membranous supravalvular aortic stenosis, with aneurysmal dilatation of the left main coronary artery and circumflex artery, associated with bicuspid aortic valve and mild aortic insufficiency. The patient died suddenly by cardiac arrest in stand by to cardiac surgery. Anatomic comprobation was not possible. The coronary artery anomalies associated with the supravalvular aortic stenosis syndrome are reviewed.  相似文献   
78.
79.
Resumen La técnica del cultivo celular es la que ha permitido conocer el comportamientoin vitro de las células cancerosas. En esta revisión pretendemos introducir las peculiaridades básicas del cultivo celular, referido especialmente a líneas cancerosas mamarias, relacionar el origen de las líneas celulares más utilizadas en la investigación de este cáncer, mencionar las técnicas de laboratorio que pueden aplicarse sobre estos cultivos y ejemplificar la utilidad de las mismas, tomando como modelo diversos trabajos que estudian los efectos del factor de crecimiento epidérmico sobre líneas celulares hormonoindependientes de cáncer de mama.   相似文献   
80.
OBJECTIVE: to assess the efficacy of rabeprazole (RPZ), amoxicillin (Am), and clarithromycin (Cla) (7 vs. 14 days) in the eradication of H. pylori, and to determine the effect of strain-specific antibiotic resistance and host CYP2C19 status. MATERIAL AND METHODS: first, we determined the CYP2C19 status of 100 healthy subjects to establish a sample size for the clinical trial. Then, 59 H. pylori-infected patients were randomized to receive RPZ (20 mg daily) plus Cla (500 mg b.d.) and Am (1,000 mg b.d.) for 7 vs. 14 days. The MIC for Am and Cla were determined using the agar dilution method. The CYP2C19 genotype was determined by the PCR-RFLP method. RESULTS: In the per-protocol analysis (PP) eradication rates were 89.7 and 72% for the 7- and 14-day groups (p = 0.159). In the intention to-treat analysis (ITT) eradication rates were 86.7 and 62.1% in the 7- and 14-day groups, respectively (p = 0.06).None of the strains was resistant to Am, and 4 strains were resistant to Cla: 3 (11.1%) in the 14-day group and 1 (4%) in the 7-day group. Neither strain-specific antibiotic resistance nor host CYP2C19 status influenced eradication rates. CONCLUSIONS: both 7- and 14-day therapies were effective for H. pylori eradication. Strain resistance and CYP2C19 status do not seem to influence eradication rates in the studied population.  相似文献   
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