Search Results
Results 451 - 500 of 1052
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Horiguchi T - - 2002
Two-month flow-through exposure experiments of tributyltin (TBT) and triphenyltin (TPhT) were conducted with abalone, Haliotis gigantea. Nominal concentrations of 100 ng TBT/l and 100 ng TPhT/l caused significant spermatogenesis in ovaries of exposed females. There were also significantly more contracted primary oocytes observed in females exposed to either TBT or ...
Morales J - - 2002
Cuentepec is a rural village of central Mexico, where 1300 pigs were bred at the time of the study in conditions that favor Taenia solium transmission. The tongues of 1087 (84%) of these pigs were visually examined and 33% were found to be cysticercotic. Castration of male pigs increased prevalence ...
Feldheim Kevin A - - 2002
Surprisingly little is known about the reproductive behaviour and breeding biology of most shark species, especially in natural populations. Here, we characterize reproductive patterns and use of a natal nursery at Bimini, Bahamas by lemon sharks, Negaprion brevirostris. We systematically and exhaustively sampled young lemon sharks at Bimini annually from ...
Evans Jennifer A - - 2002
In several mammalian species, circadian pacemakers of breeding females synchronize the developing clocks of offspring by as of yet unspecified mechanisms. The present study assessed whether maternal communication of circadian rhythms extends beyond setting pacemaker phase to include transfer of a fundamental reorganization of component circadian oscillators from dams to ...
Ohnishi Yasuyuki - - 2002
Three groups of ICR male and female mice were exposed to 50-Hz, sinusoidal, alternating, horizontal magnetic fields of 0.0 mT (sham), 0.5 mT and 5.0 mT (rms) for 9 and 2 weeks prior to mating for males and females, respectively, through fertilization and until cesarean sectioning. Fetuses were collected by ...
McAllan B M - - 2002
Antechinus stuartii is a small marsupial with a brief, highly synchronised mating period believed to be controlled by the rate of change of photoperiod. Two experiments were performed to explore aspects of photoperiodic control of the seasonal cycle. In the first experiment the pineal hormone, melatonin, administered in the drinking ...
Cho Fumiaki - - 2002
This paper reports the results of reproduction with 45 wild African green monkeys (Cercopithecus aethiops) (36 females and 9 males) during the nine years from 1981 to 1989 under indoor individually-caged conditions. In 206 cases of menstruation observed, menstrual discharge lasted for 2.5 +/- 1.2 days in cycles of 22-48 ...
Greydanus Donald E - - 2002
As the twentieth century progressed, the female athlete became an accepted participant of sports at all levels. This article reviews various aspects of female sports participation. After an historical perspective, selected comments are provided on psychologic and physiologic aspects. Concepts of adolescent gynecology are reviewed, including breast and menstrual problems ...
Garnier J N - - 2002
Female wild black rhinoceroses in Zimbabwe were monitored non-invasively using faecal progesterone metabolite analysis and observation of reproductive behaviour. A postpartum period of reproductive inactivity of at least 4 months, followed by a period of 4-7 months of oestrous cyclicity, was detected in six multiparous females. Three-quarters of the oestrous ...
Wolff Jerry O. - - 2002
We conducted a mating experiment in the laboratory using prairie voles, Microtus ochrogaster, to document that multi-male mating (MMM) can occur in this supposedly monogamous species and to test two hypotheses for the advantages of MMM in female mammals. The two hypotheses are that MMM (1) increases the probability of ...
Addo Phyllis - - 2002
The ovulatory mechanism of the grasscutter was determined in two phases. Phase one was the histological examination of ovaries of sexually mature grasscutters in various reproductive conditions (non-mated, mated, pregnant) for Corpora lutea (an indicator of ovulation). The second phase was an evaluation of the reproductive performance (female's acceptance to ...
Anolli Luigi - - 2002
The authors analyzed the suprasegmental (temporary) vocal profiles of 19 young men (not married) during their seductive interaction with 19 young women (not married) whom they had not known previously. The aim of the research was to verify the specificity, the sequential temporal stream, and the efficacy of the acoustical ...
Lourdais Olivier - - 2002
Spontaneous anorexia has been documented in various animal species and is usually associated with activities competing with food intake. In natural conditions, most female aspic vipers (Vipera aspis) stop feeding during the two months of pregnancy. We carried out a simple experiment on 40 pregnant females to determine whether anorexia ...
Mazza V - - 2002
Female pseudohermaphroditism associated with luteoma of pregnancy (LP) is a rare condition characterized by varying degrees of masculinization of a female fetus. We describe a case, diagnosed at 13 weeks gestation. Transvaginal ultrasound at 5 weeks of gestation revealed a normal intrauterine gestational sac and an enlarged maternal right ovary. ...
Wu Yuejin - - 2002
OBJECTIVE: Cardiac repolarization is prolonged and repolarization reserve (RR) is diminished in female rabbits and humans, compared to males. Reduced RR is evidenced by the relatively greater increase in ventricular action potential duration (APD) in myocytes from females in response to drugs that block repolarizing K(+) currents. Mice are an ...
Witters I - - 2002
We report a 13-week-old female fetus with early onset fetal akinesia deformation sequence (FADS) and hydranencephaly. In a previous pregnancy, the same ultrasonographic findings were noted at 13 weeks. Fetopathological examination of both female fetuses confirmed FADS with severe arthogryposis, multiple pterygia, and muscular hypoplasia. Neuropathological examination showed massive cystic ...
Duer Connie - - 2002
It has been shown in some species that fetal testes produce testosterone early in gestation. This study investigated the possibility that fetal testosterone may be reflected in maternal serum levels in the Asian elephant (Elephas maximus). Weekly serum samples were collected from seventeen pregnant captive Asian elephants and analyzed via ...
Geiger J-M - - 2002
Review of preclinical data including genotoxicity assays and a male rat reproduction toxicology study demonstrates that acitretin (Neotigason)/Soriatane) does not affect the reproductive outcome in naive females mated with treated males. Prospective studies of teratogenic risk or impairment of fertility cannot be ethically conducted in humans. However, it is highly ...
Palanza P - - 2002
There has been increasing interest, both at the scientific and regulatory level, in the use of ethological methods for evaluating neural effects of endocrine disrupters. We present a series of ethological studies on the effects of maternal exposure to low, environmentally relevant doses (0.02, 0.2, and 2 microg/g mother bw/day) ...
Jones A G - - 2001
Due to the phenomenon of male pregnancy, the fish family Syngnathidae (seahorses and pipefishes) has historically been considered an archetypal example of a group in which sexual selection should act more strongly on females than on males. However, more recent work has called into question the idea that all species ...
Walker C L - - 2001
Many factors that can modulate the risk of developing uterine leiomyoma have been identified, including parity. Epidemiological data on decreased risk of developing this disease has been subject to different interpretations regarding whether pregnancy per se is protective or, as leiomyomas are a major cause of infertility, women that develop ...
Merbs C F - - 2001
The objective of this study was to identify the presence of degenerative spondylolisthesis in adult Native American skeletons recovered from prehistoric and historic Pueblo sites in New Mexico. The vertebral columns of 491 individuals that were complete enough to allow the necessary observations produced 64 cases, with a total of ...
Dransfield R D - - 2001
An incomplete ring of electric nets was evaluated as a means of estimating trap efficiency for Glossina spp. This methodology assumes flies approach the trap directly, and then enter, or leave directly in random directions. These results showed that the ratio of the number of flies intercepted on the outside ...
Malik N M - - 2001
The ob/ob mouse has a complete absence of circulating leptin, resulting in obesity and infertility. Using the minimum daily dose of leptin required to maintain normal body weight and sexual maturation (5 mg/kg, ip), leptin-treated ob/ob females were mated with either wild-type (+/+) or leptin-treated ob/ob males. The leptin treatment ...
Latka M - - 2001
The female condom has been on the US market for over 8 years and was hailed as a method that would allow women greater control in protecting themselves against unwanted pregnancy and sexually transmitted infections. However, since its launch, promotion of the female condom has met with challenges that vary ...
Spironello Vella E - - 2001
Novel male mice can disrupt intrauterine implantation of fertilized ova in inseminated females. Evidence indicates mediation by androgen-dependent excretions. This study was designed to examine the time course of males' ability to disrupt pregnancy following castration and relate this to their urinary excretion of testosterone and 17 beta-estradiol. During days ...
Patton Z J - - 2001
Selection may act on the weakest link in fitness to change how a species adapts to an environmental stress. For many species, this limitation may be reproduction. After adult Drosophila melanogaster, Drosophila simulans, and Drosophila mojavensis males were exposed to varying levels of thermal stress well below those that endanger ...
Champagne F - - 2001
Naturally occurring variations in maternal licking/grooming influence neural development and are transmitted from mother to female offspring. We found that the induction of maternal behavior in virgin females through constant exposure to pups (pup sensitization) was significantly shorter in the offspring of High compared with Low licking/grooming mothers, suggesting differences ...
Caplan D M - - 2001
Listeria monocytogenes, an intracellular facultative germ that causes the invasion, sometimes fatal, in susceptible hosts is a food borne pathogen with ubiquitary spread that has generated a public health problem for such risk groups as: pregnant women, foetuses, new borns. 504 women with abortive disease were serologically investigated in 1999 ...
Rhind S M - - 2001
Research from a wide range of scientific disciplines has shown that the reproductive performance of animals in adult life is determined, in part, by a variety of extraneous influences acting at different stages of development from before conception until after birth. These effects are probably mediated through changes in the ...
Keisman E L - - 2001
Each Drosophila genital imaginal disc contains primordia for both male and female genitalia and analia. The sexually dimorphic development of this disc is governed by the sex-specific expression of doublesex (dsx). We present data that substantially revises our understanding of how dsx controls growth and differentiation in the genital disc. ...
deCatanzaro D - - 2001
It is well established that chemical emissions of novel males disrupt intrauterine implantation of fertilized ova in inseminated female mice, but the specific nature of these chemicals is not known. Given that novel males excrete androgens and estrogens in their urine and feces, the current experiments were designed to determine ...
Lyons E T - - 2001
A prevalence survey for hookworms (Uncinaria spp.) was done in northern fur seal (Callorhinus ursinus) and California sea lion (Zalophus californianus) pups on San Miguel Island, CA, in 2000. Intestines of dead pups were examined for adult hookworms in July. These parasites were found in 95% of 20 fur seal ...
Buczkowski G - - 2001
Horizontal transmission of insecticide occurs when foragers contact or ingest an insecticide, return to the aggregation or nest, and translocate the insecticide to the shelter and its vicinity. Relatively more sedentary members of the population then contact or eat the translocated insecticide and die. We evaluated three different methods of ...
Osada T - - 2001
Maternal recognition of pregnancy in rodents requires semicircadian surges of hypophyseal PRL secretion during early gestation, which are required for the formation of the corpus luteum of pregnancy (CLP). Here we show that puromycin-sensitive aminopeptidase (Psa)-deficient mice display female infertility that results from impaired formation of CLP. Transplantation of mutant ...
Voskuhl R R - - 2001
For decades, it has been known that females are more susceptible than males to multiple sclerosis (MS). It has also long been appreciated that during late pregnancy there is a decrease in MS disease activity. Interestingly, these two observations have also been made in an extensively used animal model for ...
Moss A M - - 2001
Slender-tailed meerkats (Suricata suricatta) are small, diurnal, cooperatively breeding mongooses of the family Herpestidae. A prerequisite to fully understanding the mating system of meerkats is the development of a normative reproductive-endocrine database. This study examined longitudinal gonadal steroid excretion in all adult and juvenile individuals of both sexes within a ...
Hwang W S - - 2001
Although the combination of artificial insemination (AI) and embryo transfer (ET) is effective for preventing large offspring syndrome in clone cattle production, it may cause freemartinism. In this study, 51 reconstructed embryos were transferred to artificially inseminated recipients. Of those 9 twin pregnancies, three delivered male and female offsprings. The ...
Touma C - - 2001
A comparative approach was used to investigate two closely related South American rodent species: the wild cavy (Cavia aperea) and the yellow-toothed cavy (Galea musteloides). These species of wild guinea-pig inhabit different habitats and show divergent social and mating systems. Cavia have a polygynous mating system, whereas in Galea promiscuous ...
Padmaja G - - 2001
Studies on stages of maturity, gonado-somatic indices and breeding cycle from two different habitats viz., the polluted Harbour Waters and the unpolluted Yerragedda Mouth revealed that M. cyprinoides breeds twice a year i.e., during Jan-Jul and Dec-Jan. Size at first maturity was 18 cm. in females and 19 cm. in ...
Esplin M S - - 2001
BACKGROUND: There is an inherited maternal predisposition to preeclampsia. Whether there is a paternal component, however, is not known. METHODS: We used records of the Utah Population Database to identify 298 men and 237 women born in Utah between 1947 and 1957 whose mothers had had preeclampsia during their pregnancy. ...
Schaffer N E - - 2001
Reproductive tracts or tissues from five male black rhinoceroses (Diceros bicornis), two male white rhinoceroses (Ceratotherium simum), two male one-horned Asian rhinoceroses (Rhinoceros unicornis), seven female black rhinoceroses, and six female white rhinoceroses from multiple institutions were examined to characterize their anatomy and histology. Some observations and measurements were obtained ...
Meurs K M - - 2001
OBJECTIVE: To determine clinical features of dilated cardiomyopathy (DCM) in Great Danes and to determine whether DCM is familial in this breed. DESIGN: Retrospective study. ANIMALS: 17 Great Danes with DCM. PROCEDURE: Medical records of Great Danes in which DCM was diagnosed on the basis of results of echocardiography (fractional ...
Tanuja M T - - 2001
Drosophila nasuta nasuta and Drosophila nasuta albomicans are cross-fertile races of Drosophila. Hybridization between these races in the laboratory has given rise to new races (Cytoraces), among which karyotypic composition differs from one another and also from those of the parental races. In this study, we search for the evidence ...
Hamasaki S - - 2001
The feasibility of fecal steroid analysis for pregnancy diagnosis and sex determination were tested in sika deer (Cervus nippon). Feces were collected from captive sika deer in June (non-breeding season and late-pregnancy period) and October (breeding season), and also from the rectum of 24 female sika deer (19 pregnant and ...
Achiron R - - 2001
A cross-sectional study of pregnant women presenting for routine fetal ultrasonographic examination was conducted at the Obstetric Ultrasonographic Unit of the Chaim Sheba Medical Center to investigate in utero development of the fetal corpus callosum (CC) in relation to fetal gender. A total of 255 consecutive healthy fetuses of low-risk ...
Jaiswal S P - - 2001
OBJECTIVE: A great degree of controversy prevails over the existing reports on the severity and outcome of acute viral hepatitis (AVH) during pregnancy. The present study describes the outcome of AVH associated with pregnancy. A correlation was also assessed for gestation period, viral etiology and outcome of AVH. METHOD: The ...
Hagelin J C - - 2001
During the breeding season, testosterone in male birds is often linked to some secondary sexual ornaments, courtship behaviors, and intrasexual aggression. I examined the effect of castration on plumage expression in Gambel's Quail (Callipepla gambelii), a species in which males are highly ornate, and in Scaled Quail (C. squamata), an ...
Halem H A - - 2001
Exposure of recently mated female mice to the urinary odours of an unfamiliar male blocks pregnancy (the Bruce effect). The absence of a pregnancy block in response to the stud male's familiar odours depends on an olfactory memory that is formed in the accessory olfactory bulb (AOB) in response to ...
Tabata A - - 2001
Mature male medaka were continuously exposed to 0.005, 0.0-5 or 1.0 ppb of estradiol-17 beta (E2 or 0.1, 10 or 100 ppb of p-nonylphenol (NP) or bis-phenol-A (BPA). Female-specific proteins (Fsp) were induced in medaka exposed to 0.005 ppb of E2, 0.1 ppb of NP, or 10 ppb of BPA. ...
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