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21.
22.
J Sabán J L Rodríguez-García J Gil J R País S Medina 《The Netherlands journal of medicine》1991,39(5-6):350-352
The aetiology of porphyria cutanea tarda (PCT) has not been elucidated, but the possibility of an autoimmune mechanism has been proposed. We report a case of an unknown clinical combination of PCT with autoimmune hypothyroidism, alopecia universalis and vitiligo with thyroid and parietal cell circulating antibodies. This is highly suggestive of underlying autoimmune damage in this patient. 相似文献
23.
M. Medina C. Barata T. Telfer D. J. Baird 《Archives of environmental contamination and toxicology》2002,42(1):17-22
Acute effects of cypermethrin, a pesticide used to treat ectoparasite infestations of salmon, were assessed using the calanoid
copepod Acartia tonsa. A. tonsa has been widely used for hazard assessment of chemicals in the marine environment using acute toxicity tests, but only with
randomly selected adults, assuming a sex ratio of 1:1. The present study assesses the environmental hazard of cypermethrin
by exposing nauplii and adult males and females, separately. Our results showed that the naupliar stages were 28 times more
sensitive to cypermethrin than adults after 96 h of exposure, with LC50s of 0.005 μg L−1 and 0.142 μg L−1, respectively. Significant differences in sensitivity between sexes were only found during the first 24 h of exposure, with
males being approximately twice as sensitive as females. The results of age-related variation in sensitivity are supported
by studies with other species of copepods and toxicants, where the increased capacity of the adults for detoxification, the
allometric differences in weight and size, and the molting process are given as explanations. Variation in sensitivity between
sexes is discussed in terms of faster depuration rates in females through egg production and implications of feeding rate
changes after 24 h of exposure. Our results suggested that standard toxicity test methods using A. tonsa are unsatisfactory because the most sensitive life stage is not included and sex-related differences in tolerance are not
taken into account. We also found that cypermethrin caused significant mortality in Acartia at exposures concentrations from one to three orders of magnitudes lower than the recommended field treatment concentration
for copepodic infestations.
Received: 27 April 2001/Accepted: 1 July 2001 相似文献
24.
The relationship of drinking and birth outcome in a US national sample of expectant mothers 总被引:3,自引:0,他引:3
Vivian B. Faden Barry I. Graubard & Mary Dufour 《Paediatric and perinatal epidemiology》1997,11(2):167-180
Alcohol consumption by pregnant women and birth outcome were studied in 9953 livebirths, 3309 fetal deaths and 5332 infant deaths from the 1988 National Maternal and Infant Health Survey. In crude analyses, race, age, mother's education, prenatal care, parity, low birthweight, gestational age, smoking and alcohol consumption during pregnancy were significantly related to the occurrence of fetal deaths and infant deaths. Among women having livebirths, race, age, mother's education, prenatal care, prematurity, gestational age, smoking and alcohol consumption during pregnancy were significantly related to having a low birthweight baby (< 2500 g). In this group, women who drank more during pregnancy also smoked more, were younger and less educated than women who drank at lower levels or not at all. The relationship of alcohol consumption during pregnancy and infant birthweight for those women having livebirths was studied using multivariable linear regression. The results indicated that race, mother's education, baby's sex, parity, mother's height, mother's body mass index and smoking, but not alcohol consumption, were significantly related to birthweight. Multivariable logistic regressions were performed for the occurrence of low birthweight, fetal death and infant death. The effect of alcohol was significant in all these analyses. These results indicate that alcohol has an important relationship with birth outcome, but that for the drinking reported in this study, the alcohol effect on mean birthweight is small relative to that of other risk factors, accounting for the non-significant result in the multiple linear regression. 相似文献
25.
J Suárez de Lezo A Medina M Pan E Hernández M Sancho A Bethencourt M Romero F Melián J Segura F Jiménez 《Revista espa?ola de cardiología》1991,44(2):106-114
We study 40 patients, 55 +/- 7 years old with acute myocardial infarction treated early by thrombolytic therapy (20 STK and 20 rt-PA). All patients were angiographically studied in the following conditions: 1) baseline, before initiating therapy. 2) Three hours after treatment. 3) Twenty four hours later. 4) Before discharge. The infarct related artery was patent 24 hours after treatment in 31 patients (78%); five of them were patent before treatment, and we observed an early reperfusion in 20 patients (57%) and late reperfusion in 6 patients (17%). The number of patients with angiographic evidence of intraluminal thrombus decreased progressively through conditions while the grade TIMI of coronary perfusion increased in the absence of reocclusion. Final regional wall motion of infarct related myocardial zones and their degree of recovery were significantly higher in recanalized patients, as compared with non-reperfused patients. Similarly, left ventricular functional recovery was higher in patients with antegrade of collateral flow to the infarct area, as compared with totally occluded patients. 相似文献
26.
27.
Michael J. Eckardt PhD Robert R. Rawlings MS Barry I. Graubard MA Vivian Faden PhD Peter R. Martin MD Louis A. Gottschalk MD PhD 《Alcoholism, clinical and experimental research》1988,12(1):88-93
Commonly used neuropsychological tests were administered to 91 detoxified alcoholics at the beginning of treatment. Statistically significant relationships were observed between test scores and post treatment consumption determined 8 months after completing treatment for 72 patients. The results varied depending upon the particular measure of posttreatment consumption evaluated and the type of statistical analysis used. The most consistent relationships were often counter to the notion that increased neuropsychological performance is correlated with a more favorable treatment outcome. Neuropsychological evaluation is of limited clinical utility in predicting posttreatment alcohol consumption. 相似文献
28.
Increasing numbers of patients are undergoing diagnostic catheterization as outpatients; however, a small proportion of patients requires hospital admission following the procedure. Unplanned admissions after consecutive outpatient cardiac catheterizations performed during 1 year were prospectively reviewed to determine the incidence of and reasons for admission. Among 847 patients undergoing outpatient cardiac catheterization, 130 patients (15%) required hospital admission after the procedure. Admitted patients were divided into four groups: patients undergoing immediate percutaneous transluminal coronary angioplasty (PTCA) (Group 1; 33%), patients with severe cardiac disease requiring urgent intervention (Group 2; 48%), patients suffering complications or hemodynamic instability (Group 3; 15%), and patients whose procedures were completed too late to allow same-day discharge (Group 4; 4%). Patients over 65 were more likely to require admission and women were more likely to be admitted with complications or hemodynamic instability. Findings are compared with results of other outpatient series, and implications regarding appropriate setting for outpatient catheterization are discussed. 相似文献
29.
30.
Eduardo Domínguez-Adame Lanuza Encarnación Jiménez Andrade Antonio Rodríguez Fernández Jaime Medina Díez 《Clinical & translational oncology》2005,7(2):78-80
Primary linitis plastica of the rectum is an infrequent and unusual rectal carcinoma. We report a new case that presented clinically as a haemorrhoidal syndrome. We comment on the characteristics--clinical picture and histopathology--of this uncommon presentation of rectal tumour, as well as its clinical history and prognosis taking into account that the literature consulted indicated the unusualness of primary linitis plastica of the rectum. 相似文献