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131.
A case of thalidomide syndrome diagnosed by ultrasound in the 17th week of pregnancy is presented. The pregnant woman had leprosy and received adjuvant treatment with thalidomide. The affected fetus was exposed to the drug until the 35th day of pregnancy and presented absent external ears, upper limb phocomelia and absent tibiae and fibulae. No internal organ abnormalities were noticed at autopsy. 相似文献
132.
The prenatal diagnosis of The Turner Syndrome is described at a menstrual age of 12 weeks. Detection of cystic hygroma was followed by vaginal chorionic villous sampling (CVS) which revealed a 45,X karyotype. Early documentation of fetal karyotype in the presence of a cystic hygroma is essential for accurate diagnosis and genetic counselling. 相似文献
133.
We report a gas chromatographic-mass spectrometric method which allows the very long chain fatty acids content of trophoblastic tissue to be directly measured in samples collected by biopsy between 8 and 11 weeks of gestation. This method has been successfully applied to the detection of fetal Zellweger syndrome in two pregnant women who had previously delivered affected infants. In one of them, increased concentrations of C26:0 (0.254 versus 0.108±0.035 μ/mg proteins) and C24:0 (1.32 versus 0.815±0.325 μ/mg proteins) in trophoblast indicated that the fetus had Zellweger syndrome, a diagnosis confirmed by pathological findings after abortion. In the second case, the pregnancy was allowed to proceed, on the basis of normal concentrations of very long chain fatty acids in trophoblastic tissue, and its outcome was actually a healthy newborn. 相似文献
134.
Leyenaar J 《Disasters》2004,28(1):1-15
Issues surrounding mother-to-child transmission of HIV/AIDS pose considerable challenges in complex humanitarian emergencies. The risk of vertical transmission through breastfeeding is well recognised, but safe alternatives are limited by the social, economic and environmental conditions of emergency situations. In 2000, the World Health Organisation published a technical report on behalf of the UNFPA/UNICEF/WHO/UNAIDS Inter-agency Task Team on Mother-to-child Transmission of HIV which outlined revised recommendations for infant feeding by HIV-positive women. This paper outlines reasons why these recommendations may be insufficient during the initial stages of complex humanitarian emergencies and proposes recommendations for establishing infant-feeding policy. Methods of mother-to-child transmission of HIV are reviewed and recent research findings are discussed. Rationale for modifying the 2000 UNFPA/UNICEF/WHO/UNAIDS infant-feeding recommendations in complex emergency situations is explored from the perspective of the infant, the mother and humanitarian field staff. Ethical limitations and future priorities are considered. The paper concludes with recommendations and a policy decision-making framework for consideration during the initial stages of humanitarian crises. 相似文献
135.
136.
137.
Survival of children with congenital diaphragmatic hernia (CDH) is mainly dependent on the extent of lung hypoplasia and the presence of additional congenital anomalies or chromosomal aberrations. A chromosomal deletion 15q25-q26.2 in a fetus with prenatally diagnosed CDH and growth retardation is reported. Despite optimal pre- and neonatal management the baby died shortly after birth. There is increasing evidence that the long arm of chromosome 15, and especially the region 15q24 to 15q26, plays a crucial role in the development of the diaphragm. The finding of a deletion within 15q24-26 in a fetus with CDH has to be considered a predictor of poor prognosis. It is of utmost interest for proper parental counselling to search in fetuses with CDH for subtle chromosomal lesions paying special attention to chromosome 15q. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
138.
Within populations of many species, individuals that are otherwise similar to one another in age, size or sex can differ markedly
in behaviours such as resource use, risk taking and competitive ability. There has been much research into the implications
of such variation for intraspecific interactions, yet little investigation into its role in influencing interspecific interactions
outside of a predator–prey context. In this study, we investigated the role of individual-level behavioural variation in determining
the outcomes of interactions between two ecologically similar fishes, the threespine and ninespine sticklebacks (Gasterosteus aculeatus and Pungitius pungitius). Experiment 1 asked whether individuals of both species were consistent in their expression of two behaviours: activity
in novel surroundings and latency to attack prey. For each behaviour, focal individuals were assayed twice, 10 days apart.
Performances were positively correlated between exposures, suggesting behavioural consistency within individuals, at least
over this timescale. Experiment 2 revealed not only differences in habitat use described both by species-level variation,
with ninespines spending more time in vegetated areas, but also by individual differences, with more active individuals of
both species spending more time in open water than in vegetation. Experiment 3 revealed that when heterospecific pairs competed
for prey, bolder individuals consumed a greater share, irrespective of species. These findings suggest that individual-level
variation can facilitate overlap in habitat use between heterospecifics and also determine the outcomes of resource contests
when they meet. We discuss how this might vary between populations as a function of prevailing selection pressures and suggest
approaches for testing our predictions. 相似文献
139.
We performed male attraction experiments and staged courtship sequences to test for non-random mating with respect to social
behavioral phenotype in the comb-footed spider, Anelosimus studiosus. While asocial behavior is the dominant phenotype in all A. studiosus populations examined to date, a social phenotype approaches a frequency of 15% in colder environments. We collected test
subjects from higher latitude polymorphic populations and scored all individuals as to their behavioral phenotype prior to
their use in these trials. Males of both phenotypes differentially approached and courted social females over asocial females
and no-spider controls. By offering males different numbers of females of one type vs. the other in subsequent trials, we
determined that the difference in attractiveness between the two phenotypes social/asocial is 1.5/1. Both the web produced
by a female and a female that has been removed from its web attract males. We suggest that the male attracting pheromone is
present on females and is also attached to silk threads. Staged encounters completed between males and females of the respective
phenotypes demonstrated that courting males suffer significantly less pre-copulatory sexual cannibalism with social females
than with asocial ones, and thus, female social tendency is phenotypically linked to sexual aggression. We propose that the
male preference for social females is adaptive because of the observed asymmetry in courtship success. 相似文献
140.