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991.
The 5 tetranucleotide short tandem repeats, HUMTHOI, HUMVWA31/A, HUMF13A1, HUMFES/FPS and HUMLPL were studied using different electrophoretic methods and PCR amplification conditions in order to optimize the typing conditions. A genetic population study in the population of Galicia was carried out and the allele and genotype frequencies are given. Compliance with the Hardy-Weinberg equilibrium was tested using different statistical parameters, with clear advantages resulting in favor of using the exact test (Guo-Thompson method) instead of conventional chi-square methods. Some statistical parameters of forensic interest (PD, CE, h) were also calculated. There were no mutations found in a total of 73 paternal meioses and 101 maternal meioses. Abnormal electrophoretic mobility was found in the AT-rich STR HUMF13AI under non-denaturing conditions and, therefore, the use of denaturing conditions is absolutely necessary. No "stutter" bands were found, although double peaks in the HUMFES/FPS system were observed in some samples. The advantage of using automated sequencers with fluorescent technology is also reported.  相似文献   
992.
Plasma retinol and -carotene levels were measured in 502 preschool Guatemalan children from five rural hamlets. Their ages ranged from 6 to 78 months (mean: 42.9±19.2 months); 45% males and 55% females. The mean retinol value in the whole group was 0.9±0.4 µmol/1 (range: 0.1 to 8.4 µmol/1). There was no significant difference between sexes in retinol mean values nor in the incidence of retinol values less than 0.7 µmol/1 (22% in males, 18% in females). When grouped by age and community, significant low retinol mean values were found in two hamlets in the youngest age group (12 to 23 months) as compared to the other age-groups (p<0.05). In the other two hamlets, there were no significant differences among retinol means by age-group. The highest prevalence of deficient retinol values by age-group was in the 12 to 23 months group (40%), and decreased as age increased. The mean value for -carotene in the whole group was 0.13±0.18 µmol/1 (range: 0.01 to 2.23 µmol/1). There were no significant differences in -carotene means between sexes in the whole group. Stratifying the -carotene data by age-groups and community, values were significantly higher in the 48–59 months and 72–83 months groups, as compared with the other age groups in two of the communities (p<0.05). Significant differences across communities for -carotene were found only in the 12 to 23 months group.  相似文献   
993.
This paper studies the effect of different concentrations of ethephon on the levels of the sesquiterpene, nootkatone, and of the flavanones, naringin and narirutin, in grapefruit fruits. The results show that nootkatone synthesis and/or accumulation was stimulated by all the concentrations of ethephon assayed, while the levels of naringin and narirutin in the rind diminished. These results open up new perspectives concerning the possible regulation of the secondary metabolism of the plants.  相似文献   
994.
Thrombosis of the hepatic artery (HAT) is a severe complication of liver transplantation, and most cases need regrafting. The aim of this study was to review our experience with this complication. From January 1986 through January 1992, 76 liver transplants were performed in 59 pediatric patients at the Children's Hospital La Paz, Madrid. The diagnosis of HAT was made in 12 cases (15.7%). The common patterns of clinical presentation were: fulminant liver necrosis (5), bile leak due to necrosis of the bile duct (4), and relapsing bacteremia (3). Clinical symptoms of fulminant liver necrosis started within the first 2 weeks after transplantation, with rapid deterioration and steep rises in SGOT and SGPT levels. All these patients were retransplanted on an urgent basis, but only 1 is alive 4 years later. Four patients developed bile leaks 13 to 60 days after transplantation; SGOT, SGPT, and total bilirubin were only slightly increased. Three children were retransplanted electively and are alive with a mean follow-up of 3 years. One exceptional patient had a Roux-en-Y jejunostomy and is doing well 30 months later with his original graft. The 3 remaining children had episodes of septicemia with hepatic abscess, liver infarction, and pleural effusion. Liver function tests were normal, with bilirubin levels below 2 mg/dl. All patients were retransplanted, but only 1 is alive and well 13 months later. In the present series, we found that early HAT produces fulminant clinical deterioration requiring an urgent regraft. Late HAT presenting with either infection or bile leak allows time for treatment by elective retransplantation. The best survival was obtained in the latter group. Correspondence to: J. Vázquez  相似文献   
995.
A dengue epidemic that Cuba reported in 1997 registered more than 500,000 cases of dengue fever produced by viral serotype 1. In 1981, there was an epidemic of dengue hemorrhagic fever produced by serotype 2 of the virus. This time 344,203 clinical cases were reported, 10,312 of which were severe cases of hemorrhagic fever that led to 158 fatalities (101 of them among children). The reintroduction of dengue, and specifically of dengue viral serotype 2 (Jamaica genotype), was quickly detected in January 1997 through an active surveillance system with laboratory confirmation of cases in the municipality of Santiago de Cuba, in the province of the same name. The main epidemiological features of this outbreak are reported in this paper. A total of 3,012 cases were reported and serologically confirmed. These included 205 cases classified as dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS), 12 of which were case fatalities (all among adults). Secondary infection with dengue virus was one of the most important risk factors for DHF/DSS. Ninety-eight percent of the DHF/DSS cases and 92% of the fatal cases had contracted a secondary infection. It was the first time dengue hemorrhagic fever was documented as a secondary infection 16 to 20 years after initial infection. Belonging to the white racial group was another important risk factor for DHF/DSS, as had been observed during the 1981 epidemic. During the most recent epidemic it was demonstrated that the so called "fever alert" is not useful for early detection of an epidemic. Measures taken by the country's public health officials prevented spread of the epidemic to other municipalities plagued by Aedes aegypti.  相似文献   
996.
Calcium plays an important role in the regulation of meiotic maturation in mammalian oocytes. In the present study, mycotoxin cyclopiazonic acid (CPA), an inhibitor of calcium-dependent ATPases, was used to mobilize intracellular calcium deposits in growing pig oocytes, which had not attained full meiotic competence and in which maturation is thus spontaneously blocked at the metaphase I stage. CPA treatment significantly increased the ratio of growing oocytes that are able to overcome the spontaneously occurring metaphase I block to complete their maturation at the metaphase II stage. CPA treatment of a least 2 hours' duration is necessary to overcome the metaphase I block in growing oocytes. A similar effect upon release from the spontaneous meiotic block at the metaphase I stage was observed after treatment of growing pig oocytes with thapsigargin, another inhibitor of endogenous calcium-dependent ATPases. Numerous calcium deposits in vacuoles, the mitochondria and on the surface of yolk granules in growing pig oocytes were observed. CPA treatment is able to mobilize calcium from the mitochondria, but deposits in vacuoles and deposits on the surface of yolk granules seem to remain intact after CPA treatment. A microinjection of heparin, which is known to bind with the inositol trisphosphate receptors, significantly decreased the ratio of CPA-treated growing oocytes overcoming the block at the metaphase I stage. This indicates that CPA might mobilize calcium in growing pig oocytes through inositol trisphosphate receptors. On the other hand, a microinjection of procaine or a microinjection of ruthenium red, both inhibitors of ryanodine receptors, did not prevent the overcoming of the metaphase I block, induced by CPA treatment. The calcium channel blocker, verapamil, significantly reduces the proportion of CPA-treated growing oocytes that overcome the metaphase I block. This indicates that the influx of calcium from extracellular sources is necessary to overcome the metaphase I block. The calmodulin inhibitors ophiobolin A and W7 also reduce the proportion of CPA-treated growing oocytes overcoming the metaphase I block.  相似文献   
997.
This article addresses women's participation in an organization development project designed to improve public sector family planning and reproductive health services in Brazil. Although community women collaborated in aspects of the intervention and research, the project nonetheless raises the basic question whether such involvement of community women does or does not correspond to what scientific writers consider to be the essence of participatory research. We review key project features in the context of recent literature and conclude that although the project is committed to the sharing of power and control, it does not fully correspond to the characteristics of participatory research. Moreover, we argue that given the project's central focus on reproductive health outcomes, complete adherence to the process-oriented, pure version of participatory research would have been inappropriate.  相似文献   
998.
The study's objectives were to determine the frequency of biological-risk accidents involving percutaneous exposure and to identify factors associated with underreporting. Two hundred fifty healthcare professionals from inpatient services at high risk for exposure at the Puerta del Mar University Hospital of Cádiz, Spain, participated in the study. A questionnaire was used to measure personal and work variables, the number of accidents suffered and reported in the last year, and the circumstances motivating the reporting or nonreporting. Two hundred thirty-two persons (92.8%) completed the questionnaire. The accident rate was 12 per 100,000 hours worked. Physicians were the most frequent accident victims (rate 22/100,000 hours). The general surgery and emergency services had higher rates than other services (rates 19.82 and 14.17, respectively). Sixty-six percent of the accidents were not reported to the register. The main predictors of the underreporting were length of professional service greater than 19 years, working in the surgery service, and the perception that the accidents did not involve health risk. The true accident rate was higher than that reflected in the Accident Register. Underreporting was high. The main variables associated with underreporting were length of professional service, work area or department, and perception of risk from the accident.  相似文献   
999.
1000.
The SMOG formula is widely used to determine how easy written health education materials are to read and comprehend. This study was conducted to assess whether the SMOG formula, originally developed and tested in English, was also valid for texts written in Spanish and French. Readability scores from a sample of passages written in Spanish, English, and French were analyzed. Study results showed that the SMOG formula seemed to be consistent in measuring readability in the three languages. However, SMOG scores varied from language to language. Two hypotheses are being laid out to explain these results. First, the SMOG equation is systematically biased for texts in Spanish or French. Second, English is more readable than French, and French is more readable than Spanish. Under the assumption of a systematic bias in the SMOG formula, the so-called SOL formulas are presented here to convert SMOG scores between Spanish, English, and French. In addition, a new scale for grading reading difficulty is proposed based on SMOG scores obtained from classical literature. This is important to the extent that it will provide Spanish speaking and French speaking health communicators with a readability formula for preparing written materials appropriate to the level of comprehension of specific target audiences.  相似文献   
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