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Results 501 - 550 of 1044
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Johnston S D - - 2000
An experiment was conducted in which female koalas were mated for different durations of intromission and ejaculation to confirm that the luteal phase of the oestrous cycle in koalas is induced by the physical act of mating. Results showed that induction of a luteal phase in the koala usually required ...
Maddison W - - 2000
Populations of the jumping spider Habronattus pugillis Griswold isolated on nearby mountain ranges in southern Arizona are differentiated in many features of the males (color, shape, and orientation of setae on face; shape of carapace; markings of palpi and legs; motions during courtship behavior). These features are (mostly) consistent within ...
Nef S - - 2000
Male sexual differentiation relies upon testicular secretion of the hormones testosterone, Mullerian inhibiting substance, and insulin-3 (Insl3). Insl3 is responsible for testicular descent through virilization and outgrowth of the embryonic gubernaculum. In mouse, prenatal exposure to 17beta-estradiol and the nonsteroidal synthetic estrogen diethylstilbestrol (DES) disturbs the endocrine balance, causing demasculinizing ...
Easton R L - - 2000
Tamm-Horsfall glycoprotein (THP) is a major glycoprotein associated with human urine that binds pro-inflammatory cytokines and also inhibits in vitro T cell proliferation induced by specific antigens. THP derived from human pregnancy urine (designated uromodulin) has previously been shown to be 13-fold more effective as an inhibitor of antigen-induced T ...
Kembra L. Howdeshell
Synopsis Individual variability in endogenous hormones can confound the interpretation of effects of developmental exposure to endocrine disrupting chemicals. In single-birth species, such as humans, there are many sources of variability in fetal sex hormone levels, such as birth order or race. In litter-bearing species a source of fetal variability ...
Jackson L M - - 2000
Previous studies of the gray short-tailed opossum have shown that ovarian activity and estrus are induced by male pheromones, but we recently documented urogenital sinus (UGS) estrus in postlactational females despite their isolation from the male stimuli known to be associated with induced estrus. Body weights and UGS smears were ...
Kerth G - - 2000
We present a microgeographic analysis of mitochondrial DNA (mtDNA) in Bechstein's bats using three sources of control region sequence variability, including a novel mtDNA microsatellite, to assess individual relatedness both within and among 10 maternity colonies. Comparison of marker variability among 268 adult females revealed little genetic variability within each ...
Englund L - - 2000
OBJECTIVE: To describe sick-listing habits in general practice, how common it is and for how long and for what diagnoses it is granted. DESIGN: Medical audit study. SETTING: Primary health care. SUBJECTS: 53 general practitioners (GPs) registering all cases during a 2-week period when sick-listing was considered. MAIN OUTCOME MEASURES: ...
Peters A - - 2000
The immunocompetence handicap hypothesis proposes that the immunosuppressive effect of testosterone enforces honesty of sexual signalling via a physiological trade-off between signal intensity and immunocompetence. However, evidence that testosterone is immunosuppressive is scant, particularly in birds. I studied the correlation between immunocompetence and testosterone in superb fairy-wrens (Malurus cyaneus), a ...
Cooper M E - - 2000
OBJECTIVE: The purpose of this study was to characterize nonsyndromic cleft lip with or without cleft palate (CL+/- CP) in an Asian population. DESIGN: Birth prevalence was assessed in a large birth series in Shanghai, China. A 1:3 sex-age-hospital matched case-control design was used to assess the effects of parental ...
Coureaud G - - 2000
The present study aimed at assessing the ability of newborn rabbits (1-3 days) to detect and discriminate abdominal odors emitted by adult conspecifics varying in sex and physiological state. Pups were submitted to a two-choice test exclusively based on olfaction, which permitted exposure to conspecifics either during successive or simultaneous ...
Lindström K - - 2000
Filial cannibalism (the consumption of one's own viable offspring) is common among fish with paternal care. In this study, I use a computer simulation to study simultaneous evolution of male filial cannibalism and female mate choice. Under certain conditions, selection on parental males favors filial cannibalism. When filial cannibalism increases ...
Yoshimura K - - 2000
Shiga toxin 2 (Stx2) is produced by enterohemorrhagic Escherichia coli (EHEC) and is known as the major virulence factor of EHEC. The aim of this study was to evaluate the effects of Stx2 on (i) maternal lethality, (ii) fetuses, (iii) delivery period, and (iv) maternal behavior after delivery. Timed pregnant ...
Clark M M - - 2000
We examined responses of adult male Mongolian gerbils to nest site and young during the hours preceding and days following birth of a litter. We found that (a) male attendance at the nest site was markedly reduced for several hours following the birth of pups; (b) this lack of contact ...
Cargill S L - - 2000
Reproductive performance was characterized in females of a line of mice homozygous for a recessive mutation with a major effect on growth, the high growth (hg) mutation. Specifically, the age at onset of puberty, length of the estrous cycle, ovulation rate, and gestation length in high growth (HG) mice were ...
Szabó T - - 2000
Secondary sexual characteristics such as softening and rounding of the abdomen as well as reddening and protrusion of the anal papilla and vent can be of help to breeders in selecting common carp (Cyprinus carpio) females prepared for propagation. To assess the reliability of this method, long-term data obtained on ...
Zacharias R - - 2000
Exposure to novel males can disrupt intrauterine implantation of fertilized ova in inseminated female mice, an effect established to involve androgen-dependent male excretions. These experiments were designed to examine potential roles of vesicular and coagulating glands, independently or in conjunction with preputial glands. Inseminated females were randomly assigned to conditions ...
Zehr J L - - 2000
The present study investigated whether peaks in female sexual initiation could accurately predict conception in group-living female rhesus monkeys. Behavioral observations, 4 or 5 days per week in large, stable, social groups of monkeys, provided frequencies of female initiation of proximity, sexual solicitation, mounts, and ejaculations. Since a preovulatory peak ...
Malas M A - - 2000
The spinal cord is situated within the vertebral canal by the third month of intrauterine life. The spinal cord possesses two symmetrical enlargements, which constitute the segments of the plexuses: the cervical enlargement for the brachial plexus and the lumbosacral enlargement for the lumbar and sacral plexus. In our study, ...
Almirón W R - - 2000
Variations in the abundance of larvae and females of Aedes albifasciatus (Macquart) were monitored biweekly during the autumn-winter periods of 1996 and 1997 on the southern edge of the Mar Chiquita Lake in Córdoba Province. The degree of development of the primary ovarian follicles also was determined in host-seeking females. ...
McLean J A - - 2000
We measured basal metabolic rate (BMR) of nonreproductive and of breeding (pregnant and lactating) female brown long-eared bats (Plecotus auritus) to investigate the effects of intra- and interindividual variation in body mass and of reproduction on metabolism. The BMR of six nonreproductive females was measured between five and seven times ...
Helversen D V DV Max-Planck-Institut für Verhaltensphysiologie, Seewiesen, Germany. - - 2001
The phonotactic behaviour of the duetting bushcricket Poecilimon ornatus was investigated on a walking compensator when two females responded to the male's call. Whenever two female clicks from different directions were presented within the time window, males tracked an intermediate course even when the two clicks were separated by up ...
Brown R E - - 1999
Inbred strains of mice exhibit different patterns of maternal behavior, providing material for studies of genetic influences on the expression of maternal behavior. Beginning 1 day after birth, maternal behavior was recorded daily for 14 days in the first and second litters of C57BL/6J (B6) and DBA/2J (D2) mothers. D2 ...
Beck S L - - 1999
To ascertain the relative contributions of genotypes of conceptus and dam to developmental toxicity occasioned by valproic acid (VPA), crosses were established between resistant C57BL/6JBk (C, C57) and susceptible SWV/Bk (S, SWV) strains of mice. These included matings of pure lines, reciprocal outcrosses, and reciprocal backcrosses with F1 hybrids. At ...
Jae Chung H - - 1999
Pregnancy block by male pheromones in mice differs in incidence depending on the combination of strains. Female mice of BALB/cA strain mated with BALB/cA males show a 100% pregnancy block when exposed to males of inbred strain DDK shortly after copulation (Chung et al., Biol Reprod 1997; 57:312-319). In the ...
Hart D A - - 1999
Tendons such as the Achilles tendon are complex structures that are hypocellular, hypovascular, and hyponeural. The development of pathophysiologic function in this tendon because of overuse is relatively common; however, the mechanisms responsible for the development of paratenonitis and tendinosis remain primarily undefined. To understand better a possible regulatory role ...
Tilbury K L - - 1999
Pilot whales strand periodically along the U.S. coast, and these strandings offer an opportunity for the collection of tissues for biomonitoring of contaminant exposure in cetaceans, as well as for specimen archiving. Concentrations of organochlorine (OC) contaminants (e.g., PCB congeners, pesticides, DDTs) were measured in tissue samples from pilot whales ...
Martrenchar A - - 1999
1. The effect of stocking density on welfare traits of turkeys was studied in 2 experiments. In each experiment 2,633 sexed BUT turkey poults were assigned to 3 rooms, 135 m2 with 1 treatment per room. Because of the large flock size (675,878 and 1080 birds in T1, T2 and ...
Cargill S L - - 1999
Animals with extreme body growth frequently experience poor reproductive performance, but the cause for this association has not been clearly established. A line of mice homozygous for the high growth (hg) mutation, a mutation that has a major effect on post-weaning growth, exhibits several reproductive deficits including an abnormally high ...
Lee S M - - 1999
Androgens have been postulated to have a major role in testicular descent via regression of the cranial suspensory ligament, which in normal rodents anchors the ovary to the retroperitoneum near the lower pole of the kidney. This study aimed to quantitate the degree of descent of the foetal ovary in ...
Hamza-Chaffai A - - 1999
Cadmium, copper and zinc were determined concomitantly with metallothionein-like proteins (MTLPs) in the subcellular fractions of Ruditapes decussatus digestive gland. This study covered 4 months and aimed to evaluate the effect of metal pollution and other factors such as sex, size and reproductive state on MTLP levels. Copper concentrations did ...
Deveci E - - 1999
Dithiocarbamate propineb and maneb are organometal fungicides, which are widely used for the control of diseases in plants. Female Wistar rats were exposed orally to 200 and 400 ppm propineb (Zn-containing dithiocarbamate) and 250 ppm maneb (Mn-containing dithiocarbamate), from the 6th day of gestation up to birth. We found that ...
Brouette-Lahlou I - - 1999
The aim of the present study was to analyze the respective roles of main and accessory olfactory systems in a particular pattern of Wistar rat maternal behavior: specific licking of pup's anogenital areas, a behavioral pattern crucial to pup survival--nonlicked pups cannot defecate, and die. Dodecyl propionate (DP), a chemical ...
Skidmore J A - - 1999
Thirty female dromedary camels were inseminated on a total of 50 occasions with 2-4 ml of fresh guanaco semen diluted with an equal volume of commercially available camel semen extender. Similarly, nine female guanacos were inseminated on 34 occasions with 4-6 ml of fresh, diluted camel semen. Only two of ...
Drickamer L C - - 1999
Seven experiments were performed to investigate pregnancy termination, urinary chemosignals, and litter sex ratio variation in female house mice. Experiments tested the effects of urine from adult and prepubertal females, housed individually or in groups, on successful insemination and litter production by females treated at different times and for different ...
de Catanzaro D - - 1999
Previous research indicates a role of pheromones in novel male-induced early pregnancy disruptions. Although some reports suggest that urine alone is sufficient to produce this effect, others raise procedural concerns and fail to replicate such effects. On Days 1 to 5 after insemination, female CF-1 mice had their nasal regions ...
Abbott B D - - 1999
The aryl hydrocarbon receptor (AHR) is a transcriptional regulatory protein that binds to upstream DNA response elements of target genes. Activation of the AHR by binding of ligands such as polyhalogenated dioxins, furans, and PCBs is associated with a wide range of adverse biological outcomes, including cancer, immune deficiencies, embryo/fetotoxicity, ...
Robertson S A - - 1999
Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been identified as a potentially important mediator of intercellular communication in the female reproductive tract, with principal target cells being the large populations of myeloid leukocytes in the cycling and pregnant uterus, the preimplantation embryo, and trophoblast cells of the developing placenta. To determine the ...
Gauthier C A - - 1999
Reproductive data are presented for female Papio papio housed in the Zoological Park of Paris and are compared with previously published data from free-ranging populations of other baboon species. The results indicate similar intermenstrual intervals and durations of sexual swelling. Sexual swelling and pregnancy are accelerated in captivity, while postpartum ...
Valeggia C R - - 1999
Titi monkeys (Callicebus spp., Cebidae) are monogamous neotropical primates that live in family-like groups typically consisting of an adult monogamous pair and one or two young. Knowledge about the reproductive biology of this genus is scanty. This study investigated the reproductive biology of female dusky titi monkeys (Callicebus moloch). An ...
Cooper R L - - 1999
Work in our laboratory has focused on the hypothesis that certain environmental contaminants will interfere with reproductive function because they disrupt the neuroendocrine regulation of gonadal function. In this article, we review the evidence that certain classes of contemporary-use pesticides alter gonadotropin secretion through a disruption of hypothalamic mechanisms. Specifically, ...
Denenberg V H - - 1999
In a recent report, a series of studies is described showing that individual differences in rat maternal licking and grooming are correlated with their offsprings' later adrenal response to a stressor (Liu et al., 1997). Pups that received more maternal stimulation in infancy had lower ACTH, corticosterone, and CRH mRNA, ...
Bonde J P - - 1999
The main objective of the Asclepios program was to examine occupational risk factors for the male reproductive system. The program focused on occupational exposure to fungicides (farmers, greenhouse workers, and vineyard workers), styrene (laminators in the reinforced plastics industry) and inorganic lead (battery workers, foundry workers, and lead smelters). Questionnaire ...
Aractingi S - - 1998
BACKGROUND: Polymorphic eruptions of pregnancy (PEP) are common cutaneous disorders of unknown origin that occur usually after week 34 of gestation. Since pregnancy is associated with peripheral-blood chimerism, particularly during the third trimester, we studied the role of fetal cells in the development of the skin lesions. METHODS: We studied ...
Chu J - - 1998
We investigated the effects of the neurohypophysial peptide, arginine vasotocin (AVT), on the calling behavior of male Acris crepitans during and immediately following a simulated acoustic agonistic encounter. AVT did not block the aggressive response to agonistic calls, as the changes in temporal call characteristics in response to the encounter ...
Hearon C M - - 1998
BACKGROUND: The standard anti-G suit (CSU-13B/P) was designed based on male body structure. Females differ from males with respect to body proportionality. In Armstrong Laboratory (AL) studies, females have terminated centrifuge simulated air combat maneuvers (SACM) because of anti-G suit (CSU-13B/P modified according to original T.O. 14P3-6-121)(OTO) discomfort. AL modifications ...
Normalina M - - 1998
Central serous choroidopathy is a spontaneous serous detachment of the sensory retina, usually affecting adults between 20 to 50 years of age but is also found in patients older than 60 years of age. This disease usually affects males with a male to female ratio of 8-10 to 1. Many ...
Neri M - - 1998
The sensitivity and specificity of the two forms of the CAMDEX interview for dementia diagnosis were assessed in a 1-year follow-up study. At the beginning of the study, 60 patients (22 males and 38 females) who met DSM-IV criteria for dementia and 60 matched controls (15 males and 45 females), ...
Swartz W J - - 1998
This study was designed to determine the ability of female mice who were exposed neonatally to the pesticide methoxychlor (MXC) to mate, ovulate, and become pregnant upon reaching sexual maturity. One-day-old female mice (5 to 8/group) were exposed daily by intraperitoneal (ip) injection for 14 d to either sesame oil ...
Pediaditakis N - - 1998
A mechanism of mate selection in humans is proposed and elaborated. It is further proposed that this mechanism constitutes one of the important factors for stability and the necessary longevity of the procreational dyad and therefore the procreational success of humans as a species. The concepts and mechanisms of assortative ...
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