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51.
52.
M. Pilar Honrubia M. Paz Herráez Rafael Alvarez 《Archives of environmental contamination and toxicology》1993,25(2):184-191
Embryos of Rana perezi were kept under laboratory conditions and treated with carbamate ZZ-Aphox® at chronic doses of 0.02 and 0.14 for 9 weeks. Both the histological study and the analysis of mortality show a direct relationship between the dosage and the effects of the pesticide. The histological study of the survivors over 56 days show damages in gills, liver, gall-bladder, heart, and notochord. Damages on the epithelia of gills (on their distal portion) and gall-bladder recover over a few days, whereas those provoked on the compacting of the hepatic parenchyma and the hepatocytes, the auricle and the perinotochordal collagenic fibers alter their structure in a lasting way. Potentials of such alterations are discussed, with special reference to the possible interference of the pesticide on the successful synthesis of the supporting connective sheaths. 相似文献
53.
García-Pergañeda A Guerrero JM Rafii-El-Idrissi M Paz Romero M Pozo D Calvo JR 《Journal of neuroimmunology》1999,95(1-2):85-94
Melatonin binding sites were characterized in mouse peritoneal macrophages. Binding of 2-[125I]melatonin by macrophages fulfills all criteria for binding to a receptor site. Thus, binding was dependent on time, temperature and cell concentration, stable, reversible, saturable and specific. Stoichiometric studies showed a high-affinity binding site with a Kd of 0.58-0.71 nM. These data are in close agreement with data obtained from kinetic studies (Kd = 0.29 nM). The affinity of these binding sites suggests that they may recognize the physiological concentrations of melatonin in serum. Moreover, binding experiments using macrophage crude membranes showed that melatonin bound specifically to the membranes. Additionally, in competition studies we observed a low-affinity binding site (Kd = 2.02 microM). Melatonin inhibited significantly forskolin-stimulated cyclic AMP accumulation in a dose-dependent manner. This effect was blocked by luzindole, an antagonist of the melatonin membrane receptor. Pretreatment of macrophages with pertussis toxin blocked the inhibitory effect of melatonin. Pertussis toxin ADP-rybosilation and Western blot experiments demonstrated both alpha(i1/2) and alpha(i3/o) G protein subunits expression in mouse peritoneal macrophages membranes. Our results demonstrate the existence of melatonin receptors in mouse peritoneal macrophages, and a pertussis toxin-sensitive melatonin signal transduction pathway that involves the inhibition of adenylyl cyclase. 相似文献
54.
55.
Summary A seroepidemiological study was carried out in order to determine the prevalence of markers of viral hepatitis infection in employees of five health-care companies and their cohabiting family members. Each participating family unit was required to fill out a questionnaire, in which, among other data, the employee was requested to indicate his or her job category. Markers of hepatitis B infection (anti-HBs, anti-HBc or HBsAg) were observed in 11.7% (58/497) of all subjects. When employees and family members were analysed according to the employee's job category, significant differences were found between staff (3%) and administrative personnel (13.3%; p<0.01) or factory workers (16.9%; p<0.01). Of 489 individuals tested for the presence of anti-HAV and anti- HCV, 59.1% and 0.6% respectively, were positive. There was a correlation between the prevalence of anti-HAV and age; a large proportion of the subjects under the age of 30 years had no evidence of prior HAV infection.
Prävalenz der Hepatitis B, A und C in einer gesunden spanischen Bevölkerungsgruppe. Aktuelle seroepidemiologische Studie
Zusammenfassung Um die Prävalenz von Virus-Hepatitis-Markern zu ermitteln, wurde eine seroepidemiologische Studie durchgeführt, in die Beschäftigte von fünf pharmazeutischen Firmen und Familienmitglieder der Wohngemeinschaft aufgenommen wurden. Fragebogen, die alle teilnehmenden Familien auszufüllen hatten, enthielten unter anderem Daten zur Berufsbezeichnung. 58 von 497 untersuchten Seren (11,7%) wiesen Marker einer Hepatitis B Virus-Infektion auf (anti-HBs, anti-HBc oder HBsAg). Nach Berufskategorie aufgeschlüsselt, fanden sich zwischen Beschäftigten und Familienmitgliedern signifikante Unterschiede: Personen, die zum Staff gehörten, waren in 3% der Fälle positiv, Verwaltungspersonal in 13,3% (p<0,01), Fabrikarbeiter in 16,9% (p<0,01). Von den 489 auf anti- HAV getesteten Personen waren 59,1 % positiv, anti-HCV-Antikörper wiesen in derselben Gruppe 0,6% der Getesteten auf. Die Prävalenz von anti-HAV zeigte eine Altersabhängigkeit; ein großer Anteil der unter 30jährigen hatte keine Marker für eine durchgemachte HAV-Infektion.相似文献
56.
For years the Wisconsin card sorting test (WCST) has been used as a test of frontal lobe function. Recent event-related potential (ERP) research has shown large differences in the amplitude of P3b responses evoked by early and late trials within each WCST series ([8]: Barceló F., Sanz M., Molina V., Rubia FJ. The Wisconsin Card Sorting Test and the assessment of frontal function: A validation study with event-related potentials. Neuropsychologia 1997;35:399-408). In this study, 16 normal subjects performed a WCST adaptation to investigate the role of attentional set shifting in these WCST P3b effects. Two control tasks were designed to examine whether early-late WCST P3b changes reflect category selection (attention) or category storage (memory) operations. Results suggest both a sharp P3b attenuation during shift WCST trials, followed by a gradual P3b build-up during post-shift trials. This P3b modulation could not be attributed to selection or storage of simple sensory stimulus dimensions, nor was it observed when the new rule was externally prompted by the first card in the WCST series. Instead, WCST P3b changes seem related to the endogenously generated shift in the perceptual rule used to sort the cards (i.e., the shift in set). The gradual build-up in P3b amplitude paralleled a progressive improvement in sorting efficiency over several post-shift WCST trials. A model based on formal theories of visual attention and attentional set shifting is proposed to account for these effects. The model offers firm grounds for prediction and bridges the gap between related clinical and experimental evidence. 相似文献
57.
Francisco Javier Torres Gómez Pilar Jurado Escámez Francisco Javier Torres Olivera 《Clinical & translational oncology》2004,6(8):493-495
Hibernoma is a rare benign tumor arising in brown fat arising in young adults with similar incidence in both sexes. They are generally subcutaneous reaching in some instances a considerable size. The interscapular region, shoulders, head and neck are the main locations, but rare cases have been described in a wide variety of sites. Histologically three types of cells mixed in different proportions corresponding to the stages of maduration of the fatty cells. They are benign tumors with not recurrence after excision. We report a pleural hibernoma, a location not reported previously in the literature. 相似文献
58.
Menéndez López V Molina Porto R Alcaraz Asensio A Gutiérrez del Pozo R Alcover García JA 《Actas urologicas espa?olas》2000,24(7):530-535
Contribution of 60 patients with primary surface transitional cell tumours of the bladder where nuclear expression of p53 protein was prospectively studied and compared to known prognostic factors in an attempt to find out its role in the development of relapses. An statistically significant relationship was found between the protein expression and cytology, tumoral multifocality, stage, relapse development and tumoral progression. It can be concluded that expression of this protein can be of use as relapse predictor. 相似文献
59.
Pilar García-Peña Javier Lucaya G. Michael A. Hendry Philip T. McAndrew Carmina Duran 《Pediatric radiology》1998,28(4):266-270
Background. Two cases of pulmonary sequestration which regressed spontaneously are presented. Objective. To demonstrate the value of imaging studies in the diagnosis and follow-up of some forms of congenital masses of the lung
in asymptomatic patients. Material and methods. We reviewed the clinical records and imaging studies of two asymptomatic children, one newborn and the other 3 months old,
with thoracic masses which demonstrated variable degrees of spontaneous involution. Results. Abdominal ultrasound performed on the newborn with a palpable mass showed a triangular echogenic mass with a large central
feeding vessel arising from the aorta. The mass had disappeared on follow-up US exam performed 6 years later. CT was performed
in the 3-month-old patient with a persistent retrocardiac mass. A soft-tissue density mass in the left pulmonary base with
a large feeding vessel arising from the aorta was visualised on contrast-enhanced CT. Five years later, a new CT scan showed
significant shrinkage of the mass and no vessel. Conclusion. Radiological techniques such as real-time US with Doppler imaging and contrast-enhanced CT may establish the diagnosis of
pulmonary sequestration by demonstrating the mass and its systemic vessel, thereby eliminating the need for more aggressive
imaging procedures. Partial or total disappearance of these masses represents a further example of involutive pathology and
suggests that not all cases of pulmonary sequestration should be surgically treated.
Received: 12 September 1997 Accepted: 18 September 1997 相似文献
60.
Fernando Arias de la Vega Miguel Angel Domínguez Domínguez Ana Manterola Burgaleta Ruth Vera García Maria Eugenia Echeverría Zabalza Eugenio Oria Mundin Enrique Martínez López Pilar Romero Rojano Elena Villafranca Iture 《Clinical & translational oncology》2005,7(2):60-65
INTRODUCTION: This study aims to asses the effectiveness and toxicity of boost radiotherapy concomitant and concurrent cisplatin for patients with locally advanced head and neck cancer (LAHNC). MATERIAL AND METHODS: There were 30 patients included in a prospective, phase II single-institution trial and of whom, 29 were at AJCC stage IV and 1 at stage III. Treatment consisted of radiotherapy acceleration fractionation with concomitant boost, 72 Gy, and 2 cycles of concomitant cisplatin (20 mg/m2/day continuous infusion; days 1-5 and 29-33). Amifostine, (i.v. 200 mg/m2) was administered to 26 prior to the first fraction of radiotherapy. Endpoints of the study were quality-of-life (QL), overall survival, and local control of disease. RESULTS: Complete response (CR) was achieved in 23 patients (77%), 2 patients had partial response (PR) (7%), 4 had no response (13%), and 1 was not evaluated for response. The 2-year overall survival and loco-regional control were 60% and 56%, respectively. Main toxicity was grade 3 or 4 mucositis in 93% of the patients. QL scores (questionnaire QLQC30; version 3.0) and the HN cancer module QLQ-HN35) showed a worsening in areas related to the treatment e.g. dry mouth, problems stretching the mouth, and sticky saliva. CONCLUSIONS: this combination modality is active, but toxic, in the treatment for LAHNC. Concomitant boost radiotherapy is probably, not the best radiotherapy schema for combining with chemotherapy in LAHNC. 相似文献