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Results 401 - 450 of 1010
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Duarte Dias Pedro Américo - - 2005
We observed a birth in a group of Mexican mantled howler monkeys (Alouatta palliata) living under semi-free-ranging conditions on Agaltepec Island, Catemaco, Veracruz, Mexico. Although we could not quantify contractions, we were able to record a complete description of the sequence of events that resulted in a successful birth. Nine ...
Isler Karin - - 2005
Vertical climbing has played an important role in theories about the evolution of habitual bipedalism in early hominids and of locomotor specialization in hominoids. However, empirical data on vertical climbing in nonhuman primates are scarce, especially regarding kinematics. In this paper, the kinematics of flexed-elbow vertical climbing of four hominoid ...
Stracci Fabrizio - - 2005
Many studies have reported increasing incidence rates of cutaneous melanoma during the last 30-40 years; the highest have been observed in Australia and New Zealand (27.9/100,000 among males and 25.0 among females) and in North America (10.9/100,000 among males and 7.7 among females). In Italy, from 1994-1998, in the areas ...
Berendonck Bettina - - 2005
The female genital structures of the entelegyne spider Latrodectus revivensis are described using semithin sections and scanning electron microscopy. Apart from the tactile hairs overhanging the opening of the atrium, the contact zones of the female epigynum are devoid of any sensilla, indicating that the female does not discriminate in ...
Córdoba-Aguilar A - - 2005
In this paper some evolutionary changes of genitalia in the damselfly Calopteryx haemorrhoidalis are investigated by determining their current and past function. Calopteryx haemorrhoidalis males stimulate females by aedeagal frictioning on a set of vaginal sensilla. The aedeagus is considerably variable and positively correlates with volumes of ejected sperm from ...
Fite Jeffrey E - - 2005
The proximate mechanisms that regulate transitions in mammalian female reproductive effort have not been widely studied. However, variation in circulating levels of the androgenic steroid hormone testosterone (T) appears to mediate a trade-off between investment in current and future offspring in males [Ketterson, E.D., Nolan, V., Jr., 1992. Hormones and ...
Nazer Dena - - 2005
Gastroesophageal reflux disease (GERD) is believed to be more common in adult males as compared to females. It also has been shown in adults to be more common in Caucasians. We wanted to determine ethnicity and gender related differences for extended pH monitoring parameters in infancy. Extended pH monitoring data ...
Nordenström A - - 2005
Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase (CYP21) deficiency causes symptoms ranging from life-threatening neonatal adrenal crises to minimal virilization in adulthood. The relationship between CYP21 genotype and phenotypic markers in a non-screened population of 73 CAH children (44 female, 29 male; 54 white, 19 Asian) treated at the Royal ...
Coe Christopher L - - 2005
The in utero environment plays a critical role in initiating the normal ontogeny of many physiological systems. As a consequence, disturbances during prenatal life can affect the baby's maturational trajectory and sometimes cause chronic alterations that influence health postpartum. Our review summarizes a series of studies in rhesus monkeys supporting ...
Fujita Shiho - - 2004
In this study we investigated the reproductive characteristics of wild female Japanese macaques (Macaca fuscata fuscata) in 2 nonconsecutive years using noninvasive methods to monitor physiological events. We detected ovulation dates and ascertained conceptions from fecal hormone profiles. First ovulations occurred from middle October to early November in 1997, and ...
Schradin Carsten - - 2004
Previous studies have found a clear relationship between prolactin (prl) and paternal care in various vertebrate taxa. In New World monkeys, it has been demonstrated in several species that fathers have high prolactin levels even during periods without infant rearing. In this study, we followed the reproductive careers of common ...
Broom Mark - - 2004
Infanticide by primate males was considered rare if groups contain more than one adult male because, owing to lower paternity certainty, a male should be less likely to benefit from infanticide. Guided by recent evidence for strong variation of infanticide in primate multi-male groups, we modelled the conditions for when ...
Lidgard D C - - 2004
Studies using molecular markers have shown that some grey seal males may be gaining success through exhibiting alternative mating tactics. We estimated the probability of fertilization success of grey seal males exhibiting the primary tactic of female defence and one alternative tactic of mating with departing females on Sable Island, ...
Watts Sarah Ann - - 2004
The reported case describes how an orphaned infant rhesus macaque (Macaca mulatta) was adopted by a non-lactating female animal from the same breeding group. Experience at our institution over the last 27 years has indicated that fostering infant rhesus macaques on to other females is unsuccessful. However, the described infant ...
Alvarez-Nava Francisco - - 2004
Female pseudohermaphroditism is a disorder in which 46,XX females with ovaries do not develop as normal women. This disorder is caused by overexposure of a female fetus to androgens during intrauterine life. We describe a masculinized female infant who was born to a mother who had virilizing signs. The patient ...
Christiansen O B - - 2004
BACKGROUND: The carriage of a male fetus often initiates maternal immunological reactions against male-specific minor histocompatibility (HY) antigens, which, in theory, could result in subsequent recurrent miscarriage (RM). METHODS: Information about subsequent pregnancy outcome was procured among 182 women with RM after a birth (secondary RM) referred since 1986 using ...
Stott Philip - - 2004
Populations of European hare (Lepus europaeus) are in decline in Europe, and populations in Australia remain at low densities. Populations are sensitive to size of the breeding stock, which is influenced by fertility in the females. From 1996 to 1999, a total of 272 adult female hares from three Australian ...
Qi Hui-Xin HX Department of Psychology, Vanderbilt University, Nashville, Tennessee 37203, - - 2004
Brain sections cut parallel to the cortical surface revealed myelin-light septa that isolated representations of the digits and parts of the face, teeth, and tongue in area 3b of adult and infant macaque monkeys. The widths of the bands of cortex representing individual digits, as measured by the distances between ...
Walker Suzanne E - - 2004
An understanding of the reproductive physiology of captive primates is vital for their successful management. We report on reproductive parameters and life-history variables collected at the Sacramento Zoo for five female golden-bellied mangabeys (Cercocebus agilis chrysogaster) over a 7-year period. For each female, we collected data on their sexual skins, ...
Fontenot M Babette - - 2004
We developed procedures to foster orphaned African green monkey infants to females with natural infants of a similar age to the foster infant (< 1 month). Our purpose was to assess the feasibility of fostering additional infants to females with natural infants. The subjects were 4 infants (age 1 to ...
Ziegler Toni E - - 2004
Male cotton-top tamarins have been shown to be responsive to female scent cues of ovulation, and are known to actively participate in infant care during the time when their mates are fertile. We measured urinary androgen levels and glucocorticoids in seven father tamarins for the first month following the birth ...
Puffer Alyssa M - - 2004
Behavioral and endocrine suppression of reproduction in subordinate females produces the high reproductive skew that characterizes callitrichid primate mating systems. Snowdon et al. [American Journal of Primatology 31:11-21, 1993] reported that the eldest daughters in tamarin families exhibit further endocrinological suppression immediately following the birth of siblings, and suggested that ...
Knopff Kyle H - - 2004
Although infanticide has been witnessed in other species of howler monkey, and has been inferred for Alouatta pigra, an observed case of infanticide has not previously been recorded for this species. Here we describe the killing of a 2-week-old infant by the resident male of a small social group in ...
Greenfeld Chuck - - 2004
The central dogma of female reproductive biology has long held that oogenesis ceases prior to birth in mammals. During the first half of the last century, there was much debate about whether this was the case or whether oogenesis continued in the postnatal ovary. A report in 1951 effectively put ...
Stein Aryeh D - - 2004
It has been suggested that maternal undernutrition results in adjustment of the sex ratio at birth, favouring females. We tested this hypothesis using births during the Dutch Hunger Winter of 1944-1945, an acute severe famine of seven months' duration. There was no evidence of an excess of female births among ...
Huang Shuang-Quan - - 2004
We tested one of the predictions of Brunet and Charlesworth (1995) that relative floral sex allocation will vary temporally with the mating environment and that the form of dichogamy (protandry vs. protogyny) will select for the pattern of variation in male versus female resource allocation. In many hermaphroditic plant species, ...
Walsh Douglas S - - 2004
Malaria vaccine RTS,S combined with thrombospondin-related anonymous protein (TRAP) and formulated with AS02A (RTS,S+TRAP/AS02A) is safe and immunogenic in adult humans and rhesus monkeys (Macaca mulatta). Here, RTS,S+TRAP/AS02A was administered on a 0-, 1-, and 3-month schedule to three cohorts of infant monkeys, along with adult comparators. Cohort 1 evaluated ...
Bochkov Andre V - - 2004
Two genera of parasitic cheyletid mites, Smileycheles Fain, 1979 (monotypic) and Thryonomycheyla Fain, 1972 (two species), are synonymized with the genus Sciurocheyla Volgin, 1969. An emended diagnosis of the genus Sciurocheyla is provided. Sciurocheyla squamosa (Domrow & Baker, 1963), type species of the genus, and Sciurocheyla camerounensis (Fain, 1979), new ...
Widdig Anja - - 2004
One of the basic tenets of sexual selection is that male reproductive success should be large in polygynous species. Here, we analysed 6 years of molecular genetic data from a semi-free-ranging population of rhesus macaques (Macaca mulatta), using Nonac's B index, to assess the level of male reproductive skew in ...
Bailey Michael T - - 2004
OBJECTIVE: The hypothesis that prenatal stress lowers the levels of protective microflora and increases the risk for postpartum Gram-negative pathogens was tested in infant monkeys. METHODS: Female monkeys were left undisturbed or were stressed during pregnancy using an acoustical startle paradigm for 6 weeks either early or late in their ...
Cook J L - - 2004
OBJECTIVE: Patellar tendinopathy has been reported to be associated with many intrinsic risk factors. Few have been fully investigated. This cross-sectional study examined the anthropometric and physical performance results of elite junior basketball players with normal or abnormal patellar tendons to see if any measures were associated with changes in ...
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 ...
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