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21.
女性泌尿生殖道支原体感染及耐药性分析 总被引:1,自引:0,他引:1
目的通过分析深圳市人民医院2009年9月至2010年4月女性泌尿生殖道支原体感染状况及耐药性变迁,指导临床合理用药。方法采用法国生物梅里埃公司MyeoplasmaIST2支原体鉴定及药敏试剂盒,进行支原体检测及药敏分析。结果2135例患者总检出率为54.6%(1166/2135),其中解脲脲支原体(Uu)阳性1017例(47.6%);人型支原体(Mh)阳性32例(1.5%);Uu+Mh阳性117例(5.5%)。1166例患者支原体对9种抗生素够感性依次为原始霉素(99.8%)、交沙霉素(99.6%)、强力霉素(96.3%)、四环素(94.4%)、克拉霉素(85.6%)、阿奇霉素(77.6%)、红霉素(75.6%)、氧氟沙星(28.4%)和环丙沙星(22.8%)。结论支原体(尤其是Uu)感染已成为女性泌尿生殖系统炎症的主要病原体之一,治疗支原体感染应选择原始霉素、交沙霉素、强力霉素等敏感率高的药物及药敏试验显示敏感的药物,喹诺酮类药物耐药率较高,应引起临床重视。 相似文献
22.
Monica L. Andersen Daniel A. Ribeiro Tathiana A. Alvarenga Paula Araujo Neuli M. Tenorio 《Hormones and behavior》2010,57(2):216-702
The aim of this investigation was to evaluate overall DNA damage induced by experimental paradoxical sleep deprivation (PSD) in estrous-cycling and ovariectomized female rats to examine possible hormonal involvement during DNA damage. Intact rats in different phases of the estrous cycle (proestrus, estrus, and diestrus) or ovariectomized female Wistar rats were subjected to PSD by the single platform technique for 96 h or were maintained for the equivalent period as controls in home-cages. After this period, peripheral blood and tissues (brain, liver, and heart) were collected to evaluate genetic damage using the single cell gel (comet) assay. The results showed that PSD caused extensive genotoxic effects in brain cells, as evident by increased DNA migration rates in rats exposed to PSD for 96 h when compared to negative control. This was observed for all phases of the estrous cycle indistinctly. In ovariectomized rats, PSD also led to DNA damage in brain cells. No significant statistically differences were detected in peripheral blood, the liver or heart for all groups analyzed. In conclusion, our data are consistent with the notion that genetic damage in the form of DNA breakage in brain cells induced by sleep deprivation overrides the effects related to endogenous female sex hormones. 相似文献
23.
The hybridogenetic fish complex Squalius alburnoides comprises diploid males with non-hybrid nuclear genomes and several hybrid forms varying in ploidy and relative proportions of the parental genomes. In this paper, we present evidence that in captivity females prefer to mate with non-hybrid males. We suggest that female choice combined with different ecological requirements of hybrid and non-hybrid males may explain the extreme variation in the relative abundance of male types among drainages.Electronic Supplementary Materials Supplementary material is available for this article at 相似文献
24.
Sexual selection is thought to drive the evolution of sexually dimorphic traits that increase male reproductive success. Despite a large degree of sexual dimorphism among haplorhine primates, phenotypic traits that may influence the reproductive success of males are largely unstudied due to long life spans and the difficulties in quantifying such traits non-invasively. Here we employ digital photogrammetry of body length and crest size, as well as ranking of the gluteal muscle size, to test whether these sexually dimorphic traits are associated with long-term measures of male reproductive success in western gorillas. Among 19 adult male gorillas monitored for up to 12.5 years, we found that all three phenotypic traits were positively correlated with the average number of mates per male, but only crest size and gluteal muscle size were significantly correlated with offspring survival and the annual rate of siring offspring that survive to weaning age. We discuss why such sexually dimorphic traits might be under ongoing selection in gorillas and other species. 相似文献
25.
Marie-Line Maublanc Eric Bideau Romain Willemet Clara Bardonnet Georges Gonzalez Lionel Desneux Nicolas Cèbe Jean-François Gerard 《Comptes rendus biologies》2012,335(12):735-743
We studied the ranging behaviour and spatial relationships between seven roe deer during more than 4 years in a partly wooded 14.2-ha enclosure. The animals (three young males, four adult females) were monitored with GPS telemetry collars. As expected, the surface area and overlap of the males’ bimonthly ranges decreased, and the distance between their arithmetic centres increased, as they became adult and, for two of them, territorial. Unexpectedly, females also tended to space out, the surface area and overlap of their bimonthly ranges being minimal in May to June, i.e. during the birth period. The distance between their arithmetic centres reached its maximum at the same time. Overlap between females’ ranges was consistently lower than those between males and females’ ranges, or between 1-year old males’ ranges. Our results raise the questions of female seasonal territoriality and of independence of the spacing systems of the two sexes in roe deer. 相似文献
26.
The lek paradox states that maintaining genetic variation necessary for 'indirect benefit' models of female choice is difficult, and two interrelated solutions have been proposed. 'Genic capture' assumes condition-dependence of sexual traits, while genotype-by-environment interactions (GEIs) offer an additional way to maintain diversity. However, condition-dependence, particularly with GEIs, implies that environmental variation can blur the relationship between male displays and offspring fitness. These issues have been treated separately in the past. Here we combine them in a population genetic model, and show that predictions change not only in magnitude but also in direction when the timing of dispersal between environments relative to the life cycle is changed. GEIs can dramatically improve the evolution of costly female preferences, but also hamper it if much dispersal occurs between the life history stage where condition is determined and mating. This situation also arises if selection or mutation rates are too high. In general, our results highlight that when evaluating any mechanism promoted as a potential resolution of the lek paradox, it is not sufficient to focus on its effects on genetic variation. It also has to be assessed to what extent the proposed mechanism blurs the association between male attractiveness and offspring fitness; the net balance of these two effects can be positive or negative, and often strongly context-dependent. 相似文献
27.
The lek paradox states that maintaining genetic variation necessary for ‘indirect benefit’ models of female choice is difficult,
and two interrelated solutions have been proposed. ‘Genic capture’ assumes condition-dependence of sexual traits, while genotype-by-environment
interactions (GEIs) offer an additional way to maintain diversity. However, condition-dependence, particularly with GEIs,
implies that environmental variation can blur the relationship between male displays and offspring fitness. These issues have
been treated separately in the past. Here we combine them in a population genetic model, and show that predictions change
not only in magnitude but also in direction when the timing of dispersal between environments relative to the life cycle is
changed. GEIs can dramatically improve the evolution of costly female preferences, but also hamper it if much dispersal occurs
between the life history stage where condition is determined and mating. This situation also arises if selection or mutation
rates are too high. In general, our results highlight that when evaluating any mechanism promoted as a potential resolution
of the lek paradox, it is not sufficient to focus on its effects on genetic variation. It also has to be assessed to what
extent the proposed mechanism blurs the association between male attractiveness and offspring fitness; the net balance of
these two effects can be positive or negative, and often strongly context-dependent. 相似文献
28.
The relationship between where a female chooses to oviposit and her larvae’s performance at those sites is critical to both
the ecology and evolution of plant-insect interactions. For predispersal seed predators that do not themselves pollinate their
host and whose larvae are sessile, females must be able to predict which flowers will ultimately be pollinated and set fruit,
or be able to manipulate flowers in some way to ensure they set fruit. Otherwise, their offspring will perish. Here we describe
the results of an experiment in which we tested if female Hylemya (Diptera: Anthomyiidae) are choosing oviposition sites wisely, or if they are manipulating flowers of their host, Ipomopsis aggregata (Polemoniaceae), in some way to ensure fruit set. Previous work in this system established a positive correlation between
oviposition and fruit set. By bagging females on flowers, we removed their ability to choose flowers on which to oviposit.
We found that flowers females oviposited on, whether bagged (”no choice”) or unbagged (”female choice”), had a significantly
higher probability of setting fruit than ”control” flowers that we bagged but did not cage females on. In addition, we tested
if Hylemya prefer particular architectural locations of flowers and if those locations correspond with higher than average fruit set.
Although flowers at the distal end of the plant, and those most proximal to the main stem, were more likely to set fruit overall, Hylemya was no more likely to oviposit on those flowers than others on the plant. Taken together, our results suggest that Hylemya is somehow able to manipulate its host to ensure fruit set and thus the provisioning of their larvae.
Received: 3 December 1999 / Accepted: 23 March 2000 相似文献
29.
Eizi Kuno 《Population Ecology》1978,20(1):50-60
Simple models are constructed to describe the rate of mating in insect populations. The models are based on the assumption of random mate-searching in a closed habitat, including four parameters, i.e., population size, sex ratio, searching efficiency and male's capacity on mating frequency. The modes of effects of these parameters on the rate of mating are analyzed and some principles deduced are discussed in relation to the mating process in natural populations. 相似文献
30.
Sexual selection is a possible mechanism of speciation. This could be true even in systems where female mate choice has not been clearly observed, because pre-existing biases may be expressed if female decision-making results in male trait evolution. In some mollies, males have enlarged dorsal fins and courtship display is the prevailing mating process. In others, male dominance is thought to play a greater role. We tested females of a species in the latter group, Poecilia mexicana, for consistent preference related to dorsal fin morphology. We found that females were biased toward larger dorsal fins. This latent preference could be an important driver in trait evolution. 相似文献