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Results 451 - 500 of 1019
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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. ...
Roth T L - - 2001
Longitudinal ultrasound and endocrine evaluations were conducted in two adult female Sumatran rhinoceroses (Dicerorhinus sumatrensis) over a period of 12-22 months to learn more about their reproductive physiology. Rectal ultrasonography was conducted to monitor ovarian activity. Blood samples were collected and analysed for progesterone and LH, and faecal samples were ...
Okkens A C - - 2001
The variation in the duration of gestation, defined as the period from mating to parturition, was studied in 113 bitches of six breeds (31 Dobermans, 31 Labrador retrievers, 14 German shepherds, 13 Bernese mountain dogs, 12 golden retrievers and 12 West Highland white terriers). The bitches were mated once on ...
Venerosi A - - 2001
BACKGROUND: The new antiretroviral treatments that combine the zidovudine (AZT) regimen with lamivudine (3TC) appear as a cost-effective alternative to the current AZT monotherapy to prevent mother-to-fetus transmission of the HIV-1 virus. Recent evidence in uninfected children raised concern about the long-term effects of perinatal exposure to AZT and 3TC, ...
Stoker T E. - - 2001
In the female rat, we have shown that a burst exposure to environmental toxicants known to alter noradrenergic function will block the ovulatory surge of LH when administered during a sensitive period on the day of vaginal proestrus. Such treatments will delay ovulation by 24 h and affect embryo survival. ...
Oehlmann J - - 2000
The effects of suspected endocrine disrupting chemicals on freshwater and marine prosobranch species were analysed in laboratory experiments. In this first publication, the responses of the freshwater snail Marisa cornuarietis and of the marine prosobranch Nucella lapillus to the xeno-estrogenic model compounds bisphenol A (BPA) and octylphenol (OP) are presented ...
Gray L E LE - - 2000
In mammals, exposure to antiandrogenic chemicals during sexual differentiation can produce malformations of the reproductive tract. Perinatal administration of AR antagonists like vinclozolin and procymidone or chemicals like di(2-ethylhexyl) phthalate (DEHP) that inhibit fetal testicular testosterone production demasculinize the males such that they display reduced anogenital distance (AGD), retained nipples, ...
Pettigrew R - - 2000
Incontinentia Pigmenti (Bloch-Sulzberger syndrome) is a rare multisystem, ectodermal disorder associated with dermatological, dental and ocular features, and in <10% of cases, severe neurological deficit. Pedigree review suggests X-linked dominance with lethality in affected males. Presentation in female carriers is variable. Following genetic counselling, a mildly affected female carrier diagnosed ...
Kurzrock E A - - 2000
PURPOSE: To determine whether the development of the rabbit phallus would be an appropriate model of human phallic development, we evaluated the formation of the fetal rabbit phallus and attempted to induce hypospadias pharmacologically. MATERIALS AND METHODS: New Zealand rabbit fetuses were obtained on gestational days 20 to 24, 26, ...
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 - - 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 ...
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