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121.
122.
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
123.
A Silvestre García C Colomer Revuelta A Nolasco Bonmatí L González Sáez C Alvarez-Dardet Díaz 《Gaceta sanitaria / S.E.S.P.A.S》1990,4(20):189-192
The study of the determinants of disease-related lifestyles may be relevant for better understanding the potential of health policies. In the present work, results of the analysis of the Elche Healthy Cities Interview Survey prevalence of some disease related lifestyles (physical activity level, cigarette consumption, and alcohol intake) are presented according to economic level as measured by monthly family income, 573 people randomly selected from the town rolls were interviewed at home. No associations were found between economic level and alcohol intake or present smoking status. But, trying to stop smoking and regular exercise were more frequent behaviors in higher economic groups. The ratio of prevalence of regular exercise was 1.73 in favor of the highest economic levels. The gradient found was statistically significant (chi 2 for trend = 17.4, p less than 0.01). The results may be of relevance when implementing health policies to overcome inequalities in health: "unequal interventions" may be more adequate. 相似文献
124.
O Moreiras-Varela C Nu?ez A Carbajal G Morande 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》1990,60(3):267-274
A nutritional study was carried out on 43 adolescents females (5 hospitalized and 38 ambulatory) suffering from anorexia nervosa and on a control group matched for sex and age. The study consisted of an interview, a "48 h. recall" and anthropometric measurements. The results have demonstrated that the nutritional status of anoretics are characterized by a total energy restriction resulting in a drastically reduced intake of macronutrients and selected micronutrients, an increased proportion of energy derived from protein. Finally, preferences and aversions are conditioned by calories content of food. 相似文献
125.
T Vera Castillo E Iglesias Díaz M Milián Montesino J B Torres Ruiz V P Díaz Narváez 《Revista cubana de enfermería》1990,6(2):151-164
A prospective study in order to determine level knowledge of the population about health, before and after the implantation of the Integral Medical Attention Programme to the Family, was carried out at the outpatient services in the "Pedro Borrás" Teaching Community Polyclinic Health Area. Of the population attending to this outpatient area, 917 individuals older than 15 years, were selected at random. These individuals were surveyed at the beginning of the study (November 1986), in order to collect data of main necessary aspects that the population must be acquainted with on health condition and health promotion, and were surveyed again after six months of the performance of the system (May 1987), and results of both surveys were compared and shown in tables with statistical data. The main programmes for health promotion before the implantation of the new system were, known, effectively, by the population in ratios ranging 0.26-0.49. After the performance of the new programme it was observed how the level of knowledge raises to 0.31-0.70, and knowledges on obesity and sedentary habits (0.69) and on prevention of accidents (0.70) becomes significative. We consider all these changes depending on a greater educational work by the physician and nurse in charge of the plan. 相似文献
126.
127.
BACKGROUND: Most of the studies which demonstrate the existence of a short-term relationship between air pollution and morbidity and the Mortality analyze the impact of "classic" pollutants which are by-products of combustion. However, the changes in the sources of these emissions, shifting basically toward road traffic, has made a change in air pollution, heightening the importance of the photochemical components, such as ozone (O3) and nitrogen dioxide (NO2). Barcelona is a city located in a mild climate zone, and its air pollution comes mainly from vehicle emissions. The main objective of this article is that of analyzing the relationship between the photochemical pollutants, NO2 and O3 and the death rate for different causes in the city of Barcelona throughout the 1991-1995 period, using the procedure for analysis set out as part of the EMECAM Project. METHODS: Daily changes in the number of deaths resulting from all causes, of the number of deaths for all causes of those over age 70, of the number of deaths resulting from cardiovascular diseases, and of the number of deaths resulting from respiratory-related causes are related to the daily changes in the photochemical pollutants using autoregressive Poisson models, controlling confusion-causing variables such as the temperature, the relative humidity, the systematic time structure and the autoregressive structure. RESULTS: Except for the relationship between O3 and the mortality for causes involving respiratory diseases, the relationships between photochemical pollutants and the mortality for all the causes considered were statistically significant. The risks related to dying as a result of rises in O3 were greater than as a result of rises in NO2, almost triple among cardiovascular diseases. The risks related to dying for all the causes are lower than for specific causes and than for those individuals over age 70. The results of the analysis by six-month periods are quite similar to the overall results, revealing, in any event, relative risks somewhat greater during the warm months (May to October). CONCLUSIONS: Photochemical pollution, especially that which is caused by O3, comprises a health risk. In the case of NO2, this might not be more than an indicators of the suspended particles or of other pollutants stemming from city traffic. There may be a certain adjustment between six-month periods of the impact of O3 on the mortality for causes of the circulatory system. 相似文献
128.
In this paper, we describe two types of putative facial motoneuron based on their electrophysiological properties and on their firing frequency adaptation as recorded in rat brainstem slices. Type I motoneurons (n = 33, 61%) were characterized by a sustained spike firing during depolarizing current injections and a marked depolarizing sag (inward rectification) during hyperpolarizing pulses. The time-course and voltage-dependence of the inward rectification together with the finding that it was blocked by Cs+ are consistent with the involvement of a Na+ -and K+ -mediated Q current. Type II motoneurons (n = 21, 39%) were identified by a fast spike firing adaptation. Type II cells showed a less pronounced inward rectification with hyperpolarizing current pulses and a higher discharge rate than type I cells during depolarizing current pulses. These distinct discharge properties imply the activation of a Ca2+ -dependent K+ current, because when carbachol was added to the bath, or the slice was exposed to a Ca2+ -free solution, a decrease was noticed in the firing frequency adaptation. The two types of motoneuron were further differentiated by the initial delay of the first spike, observed only in type I cells, which was blocked by bath application of 4-aminopyridine, indicating the presence of a K+ -mediated A current. The addition of 4-aminopyridine to the bath also increased the firing rate due to a decrease of the post-spike afterhyperpolarization. However, the two types of motoneuron were not morphologically differentiated. Facial motoneurons exhibited rhythmic membrane potential oscillations (8-20 Hz) at depolarized membrane potentials or during the silence following spike frequency adaptation. It is suggested that the intrinsic properties of these two types of facial motoneuron may be relevant in the government of distinct facial muscle activities. The fact that their discharge rate and the level of spike frequency adaptation were modified by altering some K+ currents suggests a potential plasticity in the modulation of motoneuron firing activities depending upon functional motor needs. 相似文献
129.
Gene targeting can be used for genetic studies of human cell lines and has significant potential for somatic cell gene therapy. These applications are however restricted by the low frequency of homologous recombination in higher eukaryotes compared to the relatively efficient nonhomologous integration of transfected DNA into the genome. As part of our attempts to overcome this problem, we compared two widely used transfection methods for their efficiency in gene targeting. To our surprise we found that, for conditions that render similar frequencies of nonhomologous integrants, lipofection is much less efficient than electroporation in generating targeted clones. This suggests that nonhomologous and homologous recombination have different requirements for DNA delivery in human cells. 相似文献
130.
de Aretxabala X Roa I Burgos L Cartes R Silva J Yañez E Araya JC Villaseca M Quijada I Vittini C 《The American surgeon》1999,65(3):241-246
Gallbladder cancer is generally associated with a poor prognosis, with local recurrence being the main pattern of failure. In an attempt to improve on the present status of management, we evaluated a prospective Phase II study involving preoperative 5-fluorouracil and radiation. Among 27 eligible patients with a potentially resectable gallbladder cancer detected after cholecystectomy, 18 were treated with preoperative radiation (4500 cGy; 180 cGy/fraction, 5 days/week) concurrent with a continuous infusion of 5-fluorouracil (350 mg/m2/day, days 1-5 and 21-25). Toxicity included leukopenia (8 patients) and thrombocytopenia (7 patients). Delay in surgery due to hematological toxicity was seen in 6 patients. Of the 18 patients, 15 underwent a reoperation. Resection was performed in 13 (86%). Pathologic findings after reoperation revealed residual tumor in both liver and lymph nodes in 3 patients. At a median follow-up of 24 months, 7 patients are alive. Among the patients who died after curative resection, local recurrence was demonstrated in only 1. This is the first report concerning preoperative chemoradiation in gallbladder cancer. To assess its effect on survival, a prospective randomized trial will be necessary. 相似文献