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1.
2',3'-Dihydroxy-4,4'-dimethoxychalcone (1) and 2',3',4-trihydroxy-4'-methoxy-chalcone, two new chalcones, were isolated from propolis from El Salvador. The compounds showed significant antibacterial and antifungal activity and moderate toxicity to Artemia salina nauplii.  相似文献   

2.
During the recent civil war in E1 Salvador, as in other modern wars, human rights abuses adversely affected health workers, patients, and medical facilities. The abuses themselves have been described in reports of human rights advocacy organisations but health sector adaptations to a hostile wartime environment have not. Agencies engaged in health work during the civil war adapted parties such as training of community based lay health workers, use of simple technology, concealment of patients and medical supplies, denunciation of human rights abuses, and multilevel negotiations in order to continue providing services. The Salvadorean experience may serve as a helpful case study for medical personnel working in wars elsewhere.  相似文献   

3.

The use of the kernels of Simarouba glauca as a potential source of vegetable oil was first noted in 1939. These kernels produce 62 per cent edible oil under commercial extraction procedures. The trees are polygamo-dioecious, thus creating a selection problem for commercial plantings. A progress report of investigations on the botany, propagation, selection, insect pests, and diseases is given.

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5.
We applied the IUCN Red List method for threat assessment to the amphibians and reptiles of El Salvador, the smallest Central American country. Seventy-six out of 130 species were found to be threatened or endangered at the national level. In general, most threatened taxa were aquatic organisms in lowland habitats or cloud-forest specialists in highland areas. The IUCN method was biased by collecting effort and was unable to classify 25 species that were categorized as ȁ8data deficientȁ9. We used the number and distribution of threatened species and a complementarity analysis to identify departments in El Salvador that require higher priority for conservation action. We applied a method for evaluating inventory completeness to our data set, and used species from reasonably well-surveyed taxonomic groups (Anura and Sauria) to carryout the complementarity analysis. The anurans (frogs) and saurians (lizards) had been inventoried relatively completely in 10 of 14 departments. The department with the most threatened species (35 of 76 threatened amphibians and reptiles) is Santa Ana, where many threatened species occur in pine-oak and cloud forest in Montecristo National Park.  相似文献   

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7.
Puberty represents the final stage of sexual differentiation during which time the individual acquires reproductive capacity. Puberty is not only characterized by maturation of sexual organs and the formation of oocytes and mature spermatozoa, but also by the development of secondary sexual dimorphism. In industrialized countries the age of puberty has decreased steadily over the last 150 years in association with improved socio-economic conditions. However, the decreased onset of puberty is, especially in the female sex, associated with problematic changes in behaviour such as early onset of sexual activity and resulting in high risk teenage pregnancies. First of all, the improved nutritional status during childhood is discussed as a major cause for the decrease of puberty onset, whereas the impact of nutritional status especially on female sexual maturity is discussed controversially. In our study we analysed the association between body composition (fat tissue and fat free body mass, estimated by BIA analyses), height, Body Mass Index and fat distribution, and signs of puberty such as the timing of menarche in 228 girls and voice breaking and facial hair growth in 191 boys ageing between 10 and 15 years. In both sexes signs of puberty were highly significantly associated with body composition parameters. Nevertheless, marked differences between the two sexes were observed: Female puberty was positively associated first of all with weight status and the absolute and relative amount of body fat, while in signs of male puberty were related positively with a higher amount of fat free body mass and a decreased fat mass. Male voice breaking was significantly associated with increased stature, body weight, waist and hip circumference, lean body mass and total body water, in contrast voice breaking was significantly negatively associated with the fat percentage, the total fat mass and the waist to hip ratio. Female menarche was significantly positively associated with increased body weight, weight status, waist and hip circumference but also with increased absolute and relative fat mass, relative hip circumference, lean body mass and total body water. Only the waist to hip ratio was significantly negatively associated with the onset of menarche.  相似文献   

8.

Background

From Paleo-Indian times to recent historical episodes, the Mesoamerican isthmus played an important role in the distribution and patterns of variability all around the double American continent. However, the amount of genetic information currently available on Central American continental populations is very scarce. In order to shed light on the role of Mesoamerica in the peopling of the New World, the present study focuses on the analysis of the mtDNA variation in a population sample from El Salvador.

Methodology/Principal Findings

We have carried out DNA sequencing of the entire control region of the mitochondrial DNA (mtDNA) genome in 90 individuals from El Salvador. We have also compiled more than 3,985 control region profiles from the public domain and the literature in order to carry out inter-population comparisons. The results reveal a predominant Native American component in this region: by far, the most prevalent mtDNA haplogroup in this country (at ∼90%) is A2, in contrast with other North, Meso- and South American populations. Haplogroup A2 shows a star-like phylogeny and is very diverse with a substantial proportion of mtDNAs (45%; sequence range 16090–16365) still unobserved in other American populations. Two different Bayesian approaches used to estimate admixture proportions in El Salvador shows that the majority of the mtDNAs observed come from North America. A preliminary founder analysis indicates that the settlement of El Salvador occurred about 13,400±5,200 Y.B.P.. The founder age of A2 in El Salvador is close to the overall age of A2 in America, which suggests that the colonization of this region occurred within a few thousand years of the initial expansion into the Americas.

Conclusions/Significance

As a whole, the results are compatible with the hypothesis that today''s A2 variability in El Salvador represents to a large extent the indigenous component of the region. Concordant with this hypothesis is also the observation of a very limited contribution from European and African women (∼5%). This implies that the Atlantic slave trade had a very small demographic impact in El Salvador in contrast to its transformation of the gene pool in neighbouring populations from the Caribbean facade.  相似文献   

9.
Physical growth and development of children, determined by endogenous factors (genetic and paragenetic) is modified by numerous exogenic ones. This affects differentiation of ways of growth in individual children. In order to estimate the individual growth patterns and changes in growth rate as well as differences in growth of boys and girls, one must observe the process of growth of the same children and over a period of many years (longitudinal study). Such longitudinal study is the only way to provide information about the variability of growth and growth velocity at each age.  相似文献   

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11.
In El Salvador from 1978 to 1988, contraceptive use among married women 15-44 years of age increased from 34% to 47%, and the total fertility rate declined from 6.3 to 4.6 children per woman. Most of this change took place from 1978 to 1985. Sterilization is the most prevalent method used, but nearly one-half of the women who are sterilized did not use any contraception before their operation. Few young couples use reversible methods of contraception to space births or delay the start of childbearing. On average, women wait 8 years after marriage and have nearly three children before they use contraception.  相似文献   

12.
Objective:  To identify perceived barriers to capacity building for local research ethics oversight in El Salvador, and to set an agenda for international collaborative capacity building.
Methods:  Focus groups were formed in El Salvador which included 17 local clinical investigators and members of newly formed research ethics committees. Information about the proposed research was presented to participants during an international bioethics colloquium sponsored and organized by the St. Jude Children's Research Hospital in collaboration with the National Ethics Committee of El Salvador and the University of El Salvador. Interviews with the focus group participants were qualitatively analyzed.
Results:  Participants expressed the need to tailor the informed consent process and documentation to the local culture; for example, allowing family members to participate in decision-making, and employing shorter consent forms. Participants indicated that economic barriers often impede efforts in local capacity building. Participants valued international collaboration for mutual capacity building in research ethics oversight.
Conclusions:  Research ethics committees in El Salvador possess a basic knowledge of locally relevant ethical principles, though they need more training to optimize the application of bioethical principles and models to their particular contexts. Challenges increase the value of collaborative exchanges with ethics committee members in the United States. Further research on facilitating communication between host country and sponsor country ethics committees can maximize local research ethics expertise, and thus raise the standard of protecting human participants involved in international research.  相似文献   

13.
This article explores the relationship between childhood sexual abuse (CSA) and later HIV risk. It draws on qualitative, in-depth interviews with 40 women who either used crack or engaged in commercial sex work in the greater metropolitan area of San Salvador, El Salvador, 28 of whom experienced CSA. Although the relationship between CSA and later HIV risk has been clearly demonstrated, the processes that lead women who have experienced CSA to experience HIV risk are unclear. The theoretical model presented here incorporates the psychological effects of CSA, particularly stigmatization, as well as its social consequences and the larger context of poverty in which these women live. The meanings women draw from past abuse experiences and their rationale for choices made help explain the association between CSA and later risk as mediated through sex work and crack addiction. Self-report data gathered in this study indicate that HIV prevalence may be considerably higher in this high-risk population than Salvadoran national rates.  相似文献   

14.
This study examines the functional attributes of Neotropical dung beetles, and, based on the analysis, evaluates the role of dung beetles in pastures and tropical dry forest in El Salvador. Dung beetle diversity was lower in pastures than in forests. However, the total biomass of beetles at similarly-sized dung baits was frequently higher in pastures. Diversity loss followed structured patterns: (1) carrion and fruit feeding beetles were well represented (species number) in the forests but were largely absent from pastures; (2) large ball rollers and small fast tunnellers were present in forests but were absent from pastures; (3) large fast tunnellers and small slow tunnellers were poorly represented in pastures compared to forests but the few species that survived in pastures attained extremely high populations; and (4) each functional group in the species-poor pasture assemblages was divided almost equally into day and night active species. Substrate and habitat generalists that were present in both the forests and pastures were attracted to fruit and carrion in forested habitat but not in open pastures. In open habitats, flies and other insects may be the principal decomposers of decaying fruit and carrion.  相似文献   

15.
Paleoethnobotanical studies in the Zapotitdn Valley of north-central El Salvador revealed that a species of grass,Trachypogon plumosus, was in common use as a thatch material at the Ceren site, a small mesoamerican farming community inundated by volcanic ash circaa.d. 590. Although the grass must have been common in Precolumbian times, repeated attempts to collect fresh specimens from the modern valley were unsuccessful. A survey of the major herbaria with collections from El Salvador likewise demonstrated a lack of modern specimens from the Zapotitdn Valley. The elimination of theT. plumosus from this area and its characteristic savanna habitat probably occurred as a result of the introduction of competing Old World grasses and excessive herbivory. This finding demonstrates why conservationists working in the tropics should be concerned not only with the extinction of rain forest habitats, but with the elimination of other habitats as well.  相似文献   

16.
In order to evaluate the in vitro bioactivity of LH during normal puberty compared to LH immunoactivity measured in a highly sensitive immunoassay, blood plasma samples from healthy children were analyzed in a mouse Leydig cell assay (MLCA). Blood samples were obtained from 60 healthy girls and boys during normal pubertal development. Samples were taken on two occasions with a 1-year interval. Three daytime samples and three nighttime samples were analyzed. The correlation of the LH immunoradiometric assay (IRMA) activity with the LH activity in the MLCA varied from 0.60 to 0.96 in the different pubertal stages. During pubertal development, a gradually increase in the activity of LH in both the IRMA and MLCA was found. The ratio of the in vitro bioactivity compared to the immunoreactivity (B/I ratio) did not change significantly during puberty: it was 0.84 (SD 0.58) and 0.66 (SD 0.40) during the first and second sampling period in girls and 0.88 (SD 0.38) and 0.91 (SD 0.46, NS) in the boys. The B/I ratio of LH does not change during puberty. With a high sensitivity and specificity, measurement of LH by IRMA gives representative measurements of the LH in vitro bioactivity in children during pubertal development. Copyrightz1999S. KargerAG,Basel  相似文献   

17.
The aim of this study was to investigate the anthropometric parameters and body impedance once per year during four years of the pubertal period in Estonian children. In total, 81 boys and 86 girls aged 10-11 years at the beginning of the study were investigated. Pubertal status was self-assessed by sexual maturation stages according to Tanner and physical activity index (PAI) according to Telama et al.. Body height and weight were measured and body mass index (BMI) calculated. In total, 9 skinfolds, 13 girths, 8 lengths and 8 breadths/lengths were measured according to the protocol of the International Society for the Advancement of Kinanthropometry. Somatotype components were estimated according to the method of Carter and Heath. Body impedance was measured using Multiscan 5000 (Bodystat, UK) and the impedance index (height/impedance) was calculated. The tracking of body height, weight, BMI, skinfolds, girths, lengths, breadth/lengths and body impedance was high (as a rule r> or =0.9). By increasing the time period, the correlation slightly decreased. In contrast, tracking correlations for PAI and Tanner stages were significant but quite low. Increase in mean body height was highest between 12-13 years of age (6.9 cm per year) in boys and in girls between 11-12 years of age (6.3 cm per year). In boys and girls, the peak increase in body weight was between 11 and 12 years of age, 5.7 kg and 5.2 kg, respectively. With the increasing age, body impedance decreased and impedance index increased. In conclusion, our results indicate that during puberty the detailed anthropometric parameters and body impedance tracked highly. However, the tracking of PAI and Tanner stages was significant but relatively low.  相似文献   

18.
The Santa Lucia strain of Plasmodium falciparum was isolated from El Salvador, Central America, and established in Aotus trivirgatus monkeys. Transmission from monkey to monkey via the bites of infected Anopheles freeborni, A. maculatus, and A, albimanus mosquitoes was obtained in 20 of 27 attempts. Prepatent periods in the monkeys ranged from 17 to 46 days with a mean of 24.3 days. Parasitemias and mortality were higher following sporozoite inoculation into animals which had been previously infected with P. vivax than in those with no previous malaria experience. Monkeys previously infected with P. vivax and P. cynomolgi had lower maximum parasitemias than those previously infected with P. vivax only.  相似文献   

19.
The prevalence of Type A behavior in children from lower-class rural and upper-class urban backgrounds was compared using the Hunter-Wolf A-B Self-Rating Scale (H-W A-B). Analyses of variance were performed for two levels of socioeconomic status (SES), two levels of race (black and white), two levels of gender, and two levels of age (9-11 and 13-14). A significant difference for SES was found in the predicted direction with a greater prevalence of Type A being found among upper-urban children (p less than .001). There was also a significant effect for race (p less than .0001). Although there was a significant effect for gender with boys scoring higher (p less than .001), there was no difference between boys and girls within either SES group, and both boys and girls in the upper-urban group were more Type A than boys and girls in the lower-rural group (p less than .001). The possibility that the lack of sex differences within groups may reflect changing lifestyles for young women is discussed as a topic worthy of further epidemiological investigation.  相似文献   

20.
The paper investigates the effect of child undernutrition on the risk of mortality in Burundi. Using anthropometric data from a longitudinal survey (1998–2007) we find that undernourished children, measured by the height-for-age z-scores (HAZ) in 1998 had a higher probability to die during subsequent years. In order to address the problem of omitted variables correlated with both nutritional status and the risk of mortality, we use the length of exposure to civil war prior to 1998 as a source of exogenous variation in a child's nutritional status. Children exposed to civil war in their area of residence have worse nutritional status. The results indicate that one year of exposure translates into a 0.15 decrease in the HAZ, resulting in a 10% increase in the probability to die. For boys, we find a 0.34 decrease in HAZ per year of exposure, resulting in 25% increase in the probability to die. For girls, the results are statistically not significant at the usual thresholds. We show the robustness of our results and we derive policy conclusion for a nutrition intervention in times of conflict.  相似文献   

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