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Results 401 - 450 of 974
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Neiworth Julie J - - 2004
A preference to novelty paradigm used to study human infants (Quinn, 2002) examined attention to novel animal pictures at subordinate, basic and superordinate levels in tamarins. First, pairs of pictures were presented in phases, starting with a monkey species (subordinate level) and ending with mammal and dinosaur sets (superordinate levels). ...
Elsmén E - - 2004
AIM: The aim of this study was to investigate possible gender-related differences in clinical parameters during the first week of life that could explain the higher morbidity and mortality of preterm male infants. METHODS: In total, 130 clinical variables were collected from 236 inborn infants (130 male and 106 female ...
Pollak A - - 2004
Female infants have a significantly greater chance of surviving than male infants at similar birthweights and gestational ages, and have an advantage over males for a better outcome with less morbidity. The exact mechanisms responsible for the gender differences, with a better chance of survival of female infants, remain to ...
Sandino Juan Carlos - - 2004
During 30 days male euglossine bees were bait-sampled at 12 sites, in the central Pacific coast of Colombia (ten days and four sites at each of three adjacent habitats: farmlands, highly disturbed forest and less disturbed forest) and 487 individuals were captured. Most captured individuals belonged to six species, five ...
Larson Shawnessy D - - 2004
Nerves and neuroendocrine cells located within the airway epithelium are ideally situated to sample a changing airway environment, to transmit that information to the central nervous system, and to promote trophic interactions between epithelial and mesenchymal cellular and acellular components. We tested the hypothesis that the environmental stresses of ozone ...
Kozielska Magdalena - - 2004
Genetic benefits are potentially the most robust explanation of the controversial issue of evolutionary maintenance of polyandry, but the unambiguous demonstration of such benefits has been hindered by the possibility of their confusion with maternal effects. Previous research has shown that polyandrous bulb mite females produce daughters with higher fecundity ...
Maestripieri Dario - - 2004
Mammalian play is believed to improve motor skills as well as facilitate the development of social relationships. Given the marked sexual dimorphism in gorilla body size and the role assumed by the male in protecting the group from conspecifics and predators, the motor-training hypothesis of play predicts that male infants ...
Radhakrishna Sindhu - - 2004
The slender loris (Loris lydekkerianus lydekkerianus), a nocturnal prosimian, was studied for 21 months in its natural habitat of scrub jungle in Dindigul, south India. Here we report on its reproductive biology. Identified and unidentified lorises were observed for a total of 2,656 h. Reproductive seasonality was seen, with births ...
Lavenex Pierre - - 2004
We analyzed the distribution of nonphosphorylated high-molecular-weight neurofilaments (NF-H) in the hippocampal formation of infant (3-week-old and 3-month-old) and adult (9-17-year-old) macaque monkeys in order to obtain neuroanatomical evidence of the maturity of these structures shortly after birth. We employed the monoclonal antibody SMI-32, a well-characterized antibody raised against nonphosphorylated ...
Mage David T - - 2004
Sudden Infant Death Syndrome is characterized globally by a 50% excess in males per 1000 live births of each gender. We previously hypothesized that this male excess may arise from a single X-linked gene locus with a dominant allele (p = 1/3) that is protective against potentially terminal cerebral anoxia ...
Peterka Miroslav - - 2004
The long-standing higher male birth fraction is considered an indicator of reproduction stability and health. In contrast, a decrease in the male birth fraction has been reported after prenatal exposure to environmental chemical factors. There is generally higher vulnerability of boys to prenatal damage by environmental stress. We formulated a ...
Tatarazako Norihisa - - 2003
The water flea Daphnia magna reproduces primarily by cyclic parthenogenesis. Environmental stimuli that signal a change to adverse conditions induce the organisms to switch from parthenogenesis to gamogenetic reproduction. During the gamogenetic period, they produce male daphnids and dormant resting eggs, which can survive prolonged periods of environmental adversity. However, ...
Bandyopadhyay Mridula - - 2003
Survival chances of girls in parts of South and East Asia have been adverse. Female foeticide, infanticide, abandonment, out-adoption, under-reporting of female births, and selective neglect of girls leading to higher death rates, have contributed to this adversity. Here, I reflect on an observed skewed sex ratio at birth in ...
Haccou Patsy - - 2003
When several competitors deplete a patch, it can be advantageous for each of them to stay provided that others leave, whereas, on the other hand, staying longer decreases the expected payoff for everyone. This situation can be considered as a generalized war of attrition. Previous studies have shown that optimal ...
Ma S - - 2003
We investigated the aetiology of the male phenotype in a premature infant derived from ICSI with a 46,XX karyotype. A karyotypically normal couple underwent ICSI because of obstructive azoospermia in the male partner. Sperm were retrieved by testicular sperm extraction (TESE), cryopreserved, and later used for ICSI. The pregnancy after ...
Schradin Carsten - - 2003
In biparental species, females are thought to accept and even to seek male assistance in rearing of the young. In this study, we present data that suggests that Goeldi's monkey females (Callimico goeldii) actually reject male parental care for a certain period. In Callimico, which have biparental care, mothers carry ...
Simorangkir David R - - 2003
Although a marked pubertal increase in Sertoli cell number is a hallmark of testicular development in the rhesus monkey, the ontogeny of this somatic cell type before puberty is less clear. To clarify this issue, groups (n = 4) of neonate (1-2 d old), infant (4-5 months old), juvenile (14-17 ...
Bardi Massimo - - 2003
The subtle and complex relationships between the sequential maturation of the endocrine systems during pregnancy and parturition, and the hormonal role in activating the central nervous system to express maternal behavior in primates, are far from being completely understood. Recent studies on the association between sex steroids and maternal behavior ...
Lachance Marc André - - 2003
Biodiversity theory proposes two types of hypotheses to account for the species composition of a given community. The first encompasses geographic and historical factors. For example, local species richness is thought to be affected by area, proximity to large landmasses, dispersal mechanisms, and climatic history, collectively known as biogeography. The ...
Saito Yasunori - - 2003
The morphology and life history of a strange and unidentified botryllid ascidian were investigated. This ascidian was first collected from the stony shore of Ebisu Island in Shimoda, a city on Izu peninsula in central Japan. Unlike other botryllid ascidians, whose colonies are flat and smooth, this ascidian's colonies are ...
Bearder Simon K - - 2003
This paper provides a checklist and summary of what is currently known of the variation in infant contact, sleeping site preference and aspects of social cohesion in the nocturnal primates of Africa. Genera and species are compared, based on previously unpublished field observations and a review of the literature. There ...
Nekaris K A I - - 2003
Studies of the life history parameters of slender lorises in captivity have led to conflicting results regarding gestation length, birth seasonality, interspecies variation in litter size and the degree of parental care given to offspring. During the course of field studies of Loris lydekkerianus lydekkerianus, L. l. nordicus and L. ...
Schelegle Edward S - - 2003
Twenty-four infant rhesus monkeys (30 days old) were exposed to 11 episodes of filtered air (FA), house dust mite allergen aerosol (HDMA), ozone (O3), or HDMA + O3 (5 days each followed by 9 days of FA). Ozone was delivered for 8 h/day at 0.5 ppm. Twelve of the monkeys ...
De Vleeschouwer Kristel - - 2003
Reproduction is highly demanding in terms of energy expenditure, and the costs and benefits associated with postponing or investing in a reproductive effort are crucial determinants of an individual's fitness. Understanding the reproductive potential of a species under varying ecological conditions offers important insights into the dynamics of its social ...
Marrocco G - - 2003
Cryptorchidism and proximal hypospadia in a newborn are highly suspicious for an intersex disorder, and proper investigations should be planned immediately after birth. In some hypospadic patients, the presence of a palpable gonad in the scrotum may induce to assign the male sex, whereas the anatomy of internal and external ...
Niva Cintia Carla - - 2003
Influences of photoperiod, temperature and melatonin were examined on development and color patterns of nymphs, and sternum color and reproductive fate of adults in Halyomorpha halys (brevis). Short-day accelerated nymphal development, whereas long-day accelerated reproductive maturation. The two types of photoperiodic responses at different stages may help maintain the univoltinism ...
Kennedy Michael D - - 2003
The purpose of this study was to determine the race profile for a 2000-m simulated rowing race as well as the effect of training and gender on the race profile. Nineteen men and 19 women undertook a 2000-m simulated rowing race before and after 10 weeks of a typical off-season ...
Schaal Benoist - - 2003
Mammals owe part of their evolutionary success to the harmonious exchanges of information, energy and immunity between females and their offspring. This functional reciprocity is vital for the survival and normal development of infants, and for the inclusive fitness of parents. It is best seen in the intense exchanges taking ...
Swedell Larissa - - 2003
In this work we report the first observational evidence of infanticide in wild hamadryas baboons. The study group inhabits the lowlands of the northern Rift Valley in Ethiopia and has been under observation for over 1,200 hr, on and off, since October 1996. Here we report observations from August and ...
Schradin Carsten - - 2003
The authors explored whether prolactin is associated with paternal care in 3 monkey species: titi monkey (Callicebus cupreus), common marmoset (Callithrix jacchus), and Goeldi's monkey (Callimico goeldii). They compared prolactin levels in fathers before and after infant birth as well as between fathers and nonfathers. C. cupreus fathers carry infants ...
Havill L M - - 2003
Although published normative reference standards for hematologic and clinical chemistry measures are available for adult baboons, their applicability to infants has not been addressed. We analyzed these measures in 110 infant baboons (55 females and 55 males) from a large breeding colony at the Southwest Regional Primate Research Center in ...
Herman Rebecca A - - 2003
Yearling rhesus monkey females interact more with infants than do males. However, the continuity of this sex difference throughout the juvenile period is unknown. Human females display similar sexually differentiated interest in infants, and studies of girls with congenital adrenal hyperplasia suggest that this sex difference may be modulated by ...
Foulds Nicola - - 2003
Sedaghatian type spondylometaphyseal dysplasia is a rare osteochondrodysplasia first described in 1980. The original report describes an Iranian infant with mild rhizomelic limb shortening, severe metaphyseal cupping and irregularity and platyspondyly who died shortly after birth. The baby was born to a consanguineous couple who had reportedly had two similarly ...
Uller Claudia - - 2003
Techniques traditionally used in developmental research with infants have been widely used with nonhuman primates in the investigation of comparative cognitive abilities. Recently, researchers have shown that human infants and monkeys select the larger of two numerosities in a spontaneous forced-choice discrimination task. Here we adopt the same method to ...
Schara Ulrike - - 2003
X-linked myotubular myopathy usually affects male infants with a severe phenotype leading to early death or survival with severe handicaps. Female carriers have been reported manifesting in childhood with slowly progressive muscle weakness only. The authors describe a now 5-year-old girl with prenatal/neonatal onset of an X-linked myotubular myopathy due ...
Ku Sujin - - 2003
The tapetum plays a crucial role in pollen development. This secretory tissue produces numerous nutritive proteins necessary for pollen maturation. The tapetum, whose cells undergo programmed cell death (PCD), is completely diminished by the time the pollen is fully mature. Our previous studies on a thermosensitive genic male-sterile (TGMS) rice ...
Inglis G D - - 2003
The utility of using meconia to nondestructively detect entomopathogens of lepidopterous heliothines was examined. Early-instar tobacco budworm [Heliothis virescens (F.)] or cotton bollworm [Helicoverpa zea (Boddie)] larvae were inoculated with cytoplasmic polyhedrosis virus (CPV), Serratia marcescens Bizio, or Nosema heliothidis Lutz and Splendor, and the presence of each of the ...
Tolasch Till - - 2003
Extracts of Amphimallon solstitiale (L.), a well known, widely distributed and rather common European scarab beetle, were analyzed by GC-MS and GC-EAD. Acetoin - (R):(S) > 9:1 - as well as 2,3-butanediol - (2R,3R): (2S,3S):meso = 1:1:9 - were present in extracts of both males and females. Although (2S,3S)-butanediol did ...
Pawłowski Bogusław - - 2003
Among primates, the genus Homo has a unique sexual dimorphism in general body shape. The stenotypic female "hourglass figure" has often been attributed to sexual selection. Sexual dimorphism both in shape and in position of the center of body mass (CoM) emerges during puberty and is related to hormonal influences. ...
Schneider Johanna S - - 2003
Neuroendocrine mechanisms that mediate male aggression toward infants are poorly understood. Although testosterone is known to enhance aggression in other social contexts, evidence that it modulates aggression toward infants is equivocal. We have found that male progesterone receptor knockout (PRKO) mice exhibit no infanticidal behavior and little aggression toward young. ...
Russell A J - - 2003
In eutherian mammals, sex differentiation is initiated by expression of the testis-determining gene on the Y chromosome. Subsequent phenotypic development of the reproductive tract and genitalia depends on the production of hormones by the differentiated testis. In marsupials the mechanisms of phenotypic development may vary from this pattern, as differentiation ...
Morbey Yolanda E - - 2003
We use a game-theoretic framework to investigate the reproductive phenology of female kokanee (Oncorhynchus nerka). As in the other semelparous species of Pacific salmon, females construct nests in gravel, spawn with males, bury their fertilized eggs, and defend their nest sites until they die several days later. Later-breeding females may ...
Komdeur Jan - - 2003
The Seychelles warbler (Acrocephalus sechellensis) was an endangered endemic of the Seychelles islands where, until 1988, the entire population of ca. 320 birds was restricted to the one island of Cousin Island (29 ha). Additional breeding populations were successfully established on the islands of Aride (68 ha, 1988) and Cousine ...
van Balen Frank - - 2003
Throughout recorded history, humans have tried to influence the sex of their offspring, through pregnancy injunctions, infanticide, and infant/child neglect. Reproductive technologies developed in the late 20th century allow determination of the sex of the offspring during pregnancy, making "sex selection" through abortion possible. Especially in parts of East and ...
Kinnberg Karin - - 2003
Endocrine disrupting alkylphenolic compounds have been found in the aquatic environment, and concern has arisen over the ability of these compounds to affect the reproductive system of fish. In this study, the effects of exposure to an environmentally relevant concentration of octylphenol or 17beta-estradiol on the gonad structure of fish ...
Levine Seymour - - 2003
Long-term effects of early experiences have been well documented in rodents, non-human primates and humans. The influence of early experiences on the regulation of the hypothalamic-pituitary-adrenal has demonstrated that this biological system is highly plastic and is permanently modified by early experiences. The effects of brief periods of maternal separation ...
Melo L - - 2003
Infanticide has been observed in many different species [1], including common marmosets [2-4], due to sexual selection, reproductive strategies or resource competition [3, 5, 6], which may ultimately lead to exploitation (cannibalism) [1, 7]. Wild callithrichids have a very flexible mating system, including monogamy, polygynandry, polyandry and polygyny [4, 8, ...
Hennessy Michael B - - 2003
During observations in the home cage in the light and dark on days 5, 15, 25, 35, and 45, male guinea pigs mounted and exhibited anogenital investigation of the mother, though appropriately directed mounting occurred infrequently and was not shown by all males. Mothers nipped and kicked advancing males. No ...
Meunier Martine - - 2003
Adult monkeys with late temporal lobe damage are known to touch and mouth objects compulsively, even unknown objects. To determine whether infants with early temporal damage display this symptom as well, 9-month-old rhesus monkeys with neonatal ablations of either the medial temporal lobe or inferior temporal cortex were exposed to ...
Bastian Meredith L - - 2003
We examined the effects of early rearing experience on the development of dominance status in 53 juvenile (age 3) and then in 38 adult (ages 5-8) rhesus macaques. Based on previous research investigating the behavioral outcomes of nursery-rearing, we predicted that mother-reared (MR) monkeys would outrank peer-only reared (PR) monkeys, ...
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