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1.
Scent over-marking is a common form of competitive advertisement among many species of mammals. Recent observations in golden hamsters, Mesocricetus auratushave suggested that individuals have specialized mechanisms for interpretation of and response to such over-marks. In this study, we examined whether meadow voles, Microtus pennsylvanicushave similar abilities. Female voles were first exposed to anogenital scent marks of two males and were then tested in a Y-maze for their preferences for whole-body odours of these two males. Experiments were run using a variety of configurations of scent marks during the exposure phase, but all experiments yielded consistent results. If the scent marks of the two males overlapped, females later preferred the whole-body odours of the male whose scent was on top; if the two scent marks did not overlap, females showed no preference. Females also preferred odours of familiar males over novel males, and preferred both top-scent and bottom-scent males over novel males. The results suggest that female voles can tell which individual's scent is on top in an over-mark and that they prefer this top-scent male, even though they know that both males' scents were present during the exposure phase. We suggest that these odour preferences reflect mate preferences and discuss possible reasons why females might prefer top-scent males.1997The Association for the Study of Animal Behaviour 相似文献
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Taylor Stephen A.; Burt Elaine; Hammond Greg; Relyea Kenneth 《Canadian Metallurgical Quarterly》1996,110(3):260
Some mosquitofish (Gambusia affinis holbrooki) populations contain strikingly pigmented melanistic males that are always quite rare ( 相似文献
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SA Adamo 《Canadian Metallurgical Quarterly》1998,84(3):529-533
A 38-year-old male was admitted to our hospital because of high grade fever, erythema of face and extremities and oral ulcer. The laboratory examination showed leukopenia, high titer (320 dil.) of antinuclear antibody, a positive reaction of anti-Sm antibody. Especially histopathology of hand erythema showed hydrophilic degeneration consist with chilblain lupus. Because his symptoms were consistent with the criteria of American College of Rheumatology (1982), he was diagnosed as systemic lupus erythematosus (SLE). After administration of 60 mg prednisolone daily, the symptoms gradually improved. Any recrudescence of serological abnormalities or clinical symptoms was not observed until now, although chilblain lupus still persisted. Originally SLE is frequent in young female and often attended with renal disease, central nerve disease and serositis. We reported a case of middle-aged male who developed SLE with chilblain lupus which was rare skin lesion of SLE without severe organic lesion and discussed the relation among chilblain lupus, discoid lupus erythematosus (DLE) and SLE. 相似文献
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The effects of mastitis during the late nonlactating period on colostral volume and concentrations and total yields of immunoglobulin (Ig) G1, fat, and protein in colostrum were investigated using matched pairs of mammary glands from multiparous Holstein cows. Samples of mammary secretions were collected at approximately 14 and 7 d prepartum and within 3 h after calving. At each sampling time, the glands and secretions were examined for gross abnormalities, and the California Mastitis Test was performed. Duplicate secretion samples from each gland were cultured, and somatic cell count, pH, and fat and protein concentrations were determined. The volume of colostrum obtained at the first milking of each gland was quantified using a quarter milking device, and its IgG1 concentration was measured. Colostral volume from persistently infected mammary glands was lower than that from matched uninfected glands, as was the total mass of IgG1. However, infection did not alter IgG1 concentration in colostrum. Fat and protein percentages were lower in prepartum secretions but not in colostrum from infected glands. Persistent infection was associated with increased somatic cell count and pH of secretions at all sampling times, and California Mastitis Test scores were higher for colostrum from infected glands. The appearance of secretions was extremely variable, but the presence of flakes or clots in colostrum was associated with infection. We concluded that mastitis during the late nonlactating period alters mammary gland function but is unlikely to be an important contributor to the high rate of failure of passive transfer of immunoglobulins in calves. 相似文献
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Mating systems correspond to particular ecological conditions and result from proximate interactions between individuals. We compared the mating preferences of female mice of two species: the house mouse, Mus musculus domesticus, and the mound-builder mouse, Mus spicilegus. Because of differences in their habitat, we expected to observe differences in their sexual preferences. We studied female preferences for a familiar or an unfamiliar male and the occurrence of copulation with the unfamiliar male, during two states of female sexual activity: (1) the postpartum oestrus of paired females, to evaluate the stability of their sexual partnership; and (2) the oestrus of females familiarized with a male, to study the mechanisms underlying their sexual preferences. In the polygamous house mouse, postpartum oestrous females did not show a clear preference between their familiar male and the unfamiliar one. Moreover, oestrous females, familiarized with a male (without sexual interactions), preferred an unfamiliar male and copulated with him. In contrast, postpartum oestrous females and oestrous females of M. spicilegus preferred their familiar male and rarely copulated with the unfamiliar male. This study indicates a strong pair bond in established breeding pairs in M. spicilegus and shows that this bond can be established by familiarization, which is not the case in M. m. domesticus. Our study suggests the existence of monogamous traits in M. spicilegus in contrast to the polygamous M. m. domesticus. (c) 1998 The Association for the Study of Animal Behaviour. 相似文献
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Studied (a) whether wild house mouse females would, when given a choice between males, prefer to associate with siblings or nonsiblings and (b) whether, when they exhibited a preference, prior contact was necessary for sibling recognition. Adult females were injected with hormones to induce behavioral estrus and given a paired choice of adult males with which to associate. Males were littermate siblings (LS), reared with the female until weaning; nonlittermate siblings (NLS), full siblings the female had never met; or nonsiblings (NS), unrelated and unfamiliar males. Females preferred NS males to either LS or NLS males. This indicates that they recognized siblings, even unfamiliar ones, and preferred unrelated males to siblings as potential mating partners to optimize their fitness. The females associated more with LS than NLS males, but the preference appeared to be less than strong when an unrelated male was available. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Made a film analysis of the hatching movements of White Leghorn chicks placed in transparent glass "eggshells." During every hatching burst, each of the limbs first extended, then flexed beyond the original resting point, and finally extended again to the original resting point (as seen from the body). This suggests that all 4 limbs helped to hold the body of the embryo tightly in place inside the egg during a cracking phase, enabling the beak to perform the actual cracking of the shell. Subsequently during a turning phase, the limbs contributed to rotation of the embryo in the eggshell, bringing the animal in the right position for further breaking the shell during the next burst. The effective forces against the shell, leading to rotation of the animal in the egg, were probably performed by (a) the right leg during its flexion, (b) the right wing during its flexion, and (c) the left wing during its re-extension. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Ovaries from house flies maintained on sucrose secrete large amounts of ecdysteroid when they are cultured with ovarian ecdysteroidogenic hormone, OEH. However, ovarian ecdysteroid secretion is reduced by incubation with both OEH and the ovarian ecdysteroidostatin (OES). A partially purified OES fraction from a semi-preparative reverse phase HPLC C18 column caused a 98% inhibition of ovarian ecdysteroid secretion in vitro at a concentration of 0.8 equivalents per microliter. Ovaries can be activated to produce ecdysteroid in vivo by feeding diet containing protein to flies maintained on sucrose. Ecdysteroid secretion was inhibited when the in vivo stimulated ovaries were cultured with OES. This suggests that OES does not interfere with the OEH activation mechanism, but blocks ovarian ecdysteroid synthesis or release. Furthermore, OES inhibition is reversible and ecdysteroid secretion resumes when OES is removed. Musca OES could explain the decrease in ecdysteroid levels found in flies after mid-vitellogenesis. Both adult male and female abdomens contain OES, but OES was not transferred to females during mating. Evidence is presented that OES is not a trypsin modulating oostatic factor. 相似文献
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Recent studies of large ganglion cells in fishes and frogs have identified a shared inventory of three basic types, with characteristic forms and spatially independent mosaic distributions. These anamniote types and mosaics are hard to match to the large ganglion cell types and mosaics of mammals, implying that the underlying developmental programmes have diverged during evolution. Reptiles and mammals both belong to the amniote lineage, so the point of divergence can be investigated by comparing the large ganglion cells of reptiles with those of mammals, taking fishes and frogs as outgroups. With this aim, ganglion cells of the common house gecko, Hemidactylus frenatus, were labelled with horse-radish peroxidase by an in vitro method and studied in retinal flatmounts. Two prominent, regular, spatially independent mosaics were consistently present. One (alpha a) was characterized by somata displaced into the inner nuclear layer and dendrites forming planar trees in sublamina a; the other (alpha ab) comprised large orthotopic somata and distinctive, bistratified dendrites that formed discrete planar subtrees in sublaminae a and b. These subtrees were joined by up to 40 vertical link segments, whose distribution was found to correlate with the underlying photoreceptor mosaic. Some specimens also contained patches of a third mosaic (alpha c), characterized by large orthotopic somata and very large flat trees in sublamina c, but the labelling of this type was inconsistent. These reptilian mosaics share several distinctive characters with anamniote alpha-cell mosaics but differ markedly from the ganglion cell mosaics of any known mammal. The most parsimonious conclusion is that those mosaic features that are shared by the ganglion cells of all nonmammals are homologous and primitive (symplesiomorphic), while those that are shared by all therian mammals are homologous and derived (synapomorphic). This is consistent with other differences between mammalian and nonmammalian eyes. Mosaic formation itself, however, seems to be a universal characteristic of large ganglion cells. 相似文献
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A cluster epidemic of 13 Morganella morganii infections involving 11 patients occurred over a 3-month period in 1977. This epidemic was unusual in that it involved four services and five hospital floors. The outbreak was effectively terminated when strict asceptic techniques were reinforced. 相似文献
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This study was undertaken to test the hypothesis that a group of normal male siblings of schizophrenics (N-Sc) will agree with a group of male schizophrenic siblings (Sc-N) in their perception of their mothers' child-rearing attitudes and will perceive these attitudes as being more deviant (undesirable) than a group of normal males whose siblings are all normal (N-N). Perception was measured on a child-study questionnaire which Ss were instructed to answer as they thought their mothers would have when Ss were growing up. The results were that the normal siblings of schizophrenics perceive their mothers' attitudes as being more martyred and subtly dominating than do normal siblings of normals (p = .05). There were no other significant differences, although the trend was toward perception of maternal attitudes as least deviant by the N-N group, most deviant by the N-Sc group, and in-between by the Sc-N group. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Cutaneous electrogastrography (EGG) allows the measurement of gastric electrical activity. An association of EGG with gastrointestinal motility disorders has been shown. Abnormalities of electrical rate or rhythm are accepted as the most important parameters in EGG. However, the reliability of the magnitude of electrical amplitude in the assessment of motility is discussed controversially. Therefore in a prospective study we investigated the relation between amplitude and antral contractions by means of ultrasonography. 8 healthy volunteers (4 men, 4 women, 24-31 years) ingested 400 ml carbonated mineral water after an overnight fast at two separate study days. Over a period of 10 min preprandial and 10 min postprandial small and intense antral contractions were measured employing sagittal antral planimetry. Simultaneous amplitudes were determined during contractions and at 1 min intervals (average amplitude) by cutaneous electrogastrography. Data were analyzed by Wilcoxon's rank sum test and Spearman rank correlation test. The coefficient of variation of the postprandial/preprandial amplitude ratio was nearly two times greater between subjects than between recordings in the same subject, which reflects a moderate intraindividual reproducibility. We found a significant increase in the average amplitude postprandially (p < 0.05). Although postprandial contractions (n = 243) predominated preprandial contractions (n = 127) significantly (p = 0.02), no significant correlation between the number of contractions and the average amplitude existed (R = 0.1; p = 0.7). Moreover the average amplitude did not differ from amplitudes during intense and small contractions significantly (p = 0.7; p = 0.1). The magnitude of the amplitude measured by EGG does not correlate with the mechanical gastral activity significantly.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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依据底商住宅楼的施工图 ,立足工程造价预算专业 ,以土建工程造价控制为主 ,配套以给排水系统、电气照明系统为辅 ,对施工图预算进行统计分析 ,便于今后类似工程的投资控制提供参考 相似文献
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Infants prefer native structures such as familiar faces and languages. Music is a universal human activity containing structures that vary cross-culturally. For example, Western music has temporally regular metric structures, whereas music of the Balkans (e.g., Bulgaria, Macedonia, Turkey) can have both regular and irregular structures. We presented 4- to 8-month-old American and Turkish infants with contrasting melodies to determine whether cultural background would influence their preferences for musical meter. In Experiment 1, American infants preferred Western over Balkan meter, whereas Turkish infants, who were familiar with both Western and Balkan meters, exhibited no preference. Experiments 2 and 3 presented infants with either a Western or Balkan meter paired with an arbitrary rhythm with complex ratios not common to any musical culture. Both Turkish and American infants preferred Western and Balkan meter to an arbitrary meter. Infants’ musical preferences appear to be driven by culture-specific experience and a culture-general preference for simplicity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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S Fujii K Ono S Shigeta S Oka T Jyo U Yamashita 《Canadian Metallurgical Quarterly》1996,49(1-2):37-42
Hong Kong, Taiwan, Singapore, and Malaysia are initiating health care reform to meet the changing demands of populations with improved socioeconomic status and access to modern technologies and who are living longer than in previous generations. Hong Kong, in particular, is facing a unique set of circumstances as its people prepare for the transition in 1997 from a British colony to a Special Administrative Region of China. While spending only 4% of its gross domestic product on health care, it has a large and regulated public hospital system for most inpatient medical care and a separate, loosely regulated private health care system for most outpatient medical care. In 1993 the Secretary for Health and Welfare of Hong Kong initiated a year-long process to debate the pros and cons of 5 fundamental programs for health care reform. After a year of open consultation, options were chosen. We describe the Hong Kong health care system, the fundamental changes that have been adopted, and lessons for reformers in the United States. 相似文献
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In chick, the tectal and posterior commissures form a continuous band of axons lying in the dorsal aspect of the meso-diencephalon. In midline sagittal sections, two zones can be clearly defined. The rostral zone (RZ) contains about 290,000 axons of which 32% are myelinated. The caudal zone (CZ) contains about 911,000 fibers of which 12% are myelinated. The majority of unmyelinated fibers in RZ and CZ are between 0.15 and 0.40 micrometers in diameter. The majority of myelinated fibers in both RZ and CZ are less than 1 micrometer in diameter. It is likely that RZ corresponds to the posterior commissure while CZ corresponds to the tectal commissure. 相似文献