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61.
62.
Wen-Rong Li  Li-Zhen Li 《ZooKeys》2013,(348):89-95
The male of Lobrathium rotundiceps (Koch, 1939) from Zhejiang and L. luoxiaoense sp. n. from Jiangxi are described and illustrated.  相似文献   
63.
Calymmochilus dispar Bouček & Andriescu (Hymenoptera, Eupelmidae) and Gelis apterus (Pontoppidan) (Hymenoptera, Ichneumonidae) are newly recorded as parasitoids of the ant-eating spider Zodarion styliferum (Simon) (Araneae, Zodariidae). The larvae of both parasitoid species fed on juvenile spiders. The final instar larva and pupa of Calymmochilus dispar and the male of Gelis apterus are described for the first time. Both species represent new distribution records for Portugal. The biology and host associations of the parasitoids are discussed.  相似文献   
64.
《Biomarkers》2013,18(5):402-406
The H2B family, member W, testis specific (H2BFWT) gene encodes a testis specific histone that plays a crucial role in reorganization and remodeling of chromatin and epigenetic regulation during spermatogenesis, suggesting that the gene may be involved in spermatogenesis impairment. To test the speculation, the allele and haplotype frequencies of two single-nucleotide polymorphism loci in this gene, ?9C>T and 368A>G, were investigated in 409 infertile patients with idiopathic azoospermia or oligozoospermia and 209 fertile men as controls using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) assay. As the results, the frequencies of ?9T (52.8% vs. 41.6%, p = 0.009) and 368G (43.0% vs. 32.5%, p = 0.012) were significantly higher in patients than those in controls; after stratifying patients, the significant higher frequencies were still detected in allele ?9T for azoospermia (57.4% vs. 41.6%, p = 0.001) and allele 368G for oligozoospermia (45.4% vs. 32.5%, p = 0.007). The haplotype CA was significantly decreased (22.8% vs. 33.0%, p = 0.006) whereas TG was significantly increased (18.3% vs. 7.2%, p < 0.001) in infertile patients compared with controls. These results indicated that the polymorphism ?9C>T and 368A>G in H2BFWT gene are associated with male infertility with idiopathic azoospermia or oligozoospermia, suggesting that H2BFWT gene might be contribute to susceptibility to spermatogenesis impairment in Chinese population.  相似文献   
65.
Costs of sexual interactions play a key role in life‐history evolution. Although the costs of reproduction have been investigated in both sexes of many insects, the costs of same‐sex interactions have been examined in few species. In parasitic wasps, very little has been reported about the longevity costs of heterosexual interactions, and nothing is known about longevity costs of same‐sex interactions. In this study, the effects of heterosexual and homosexual activities on longevity were evaluated in Psyttalia concolor (Hymenoptera: Braconidae), a synovigenic koinobiont larval‐pupal endoparasitoid of tephritid flies. When compared with individually housed virgin wasps, male longevity was strongly reduced both in males kept with females, and in males kept with other males. When females were kept with males, their longevity was reduced compared with the virgin females and females kept with other females. Overall, the costs of male–female interactions were considerable in both sexes of P. concolor, while same‐sex activities were found to be costly only among males, suggesting that they may have implications for the evolution of the P. concolor mating system.  相似文献   
66.
《Biomarkers》2013,18(5):412-417
Abstract

In testis, eNOS is responsible for synthesis of nitric oxide (NO) which is an essential gas message regulator in spermatogenesis, suggesting that eNOS gene plays a role in normal spermatogenesis and the genetic variants of eNOS gene may be potential genetic risk factors of spermatogenesis impairment. In this study, the polymorphic distributions of three common polymorphism loci including T-786C, 4A4B and G894T in eNOS gene were investigated in 355 Chinese infertile patients with azoospermia or oligozoospermia and 246 healthy fertile men and a meta-analysis was carried in order to explore the possible relationship between the three loci of eNOS gene and male infertility with spermatogenesis impairment. As a result, allele -786C of T-786C (11.4% versus 6.5%, p?=?0.004) and 4A of 4A4B (11.0% versus 6.3%, p?=?0.005) as well as genotype TC of T-786C (22.8% versus 13.0%, p?=?0.002) and AB of 4A4B (18% versus 11%, p?=?0.015) were significantly associated with idiopathic male infertility. The haplotypes T-4A-G (7.4% versus 4.1%, p?=?0.015) and C-4B-G (7.6% versus 4.4%, p?=?0.028) could increase the susceptibility to male infertility, whereas haplotype T-4B-G (67.0% versus 75.2%, p?=?0.002) might be a protective factor for male infertility. The results of meta-analysis revealed that the polymorphism of T-786C was associated with male infertility. These findings suggested that the variants of eNOS gene may modify the susceptibility to male infertility with impaired spermatogenesis.  相似文献   
67.
Species interacting in varied ecological conditions often evolve in different directions in different local populations. The butterflies of the cryptic Leptidea complex are sympatrically distributed in different combinations across their Eurasian range. Interestingly, the same species is a habitat generalist in some regions and a habitat specialist in others, where a sibling species has the habitat generalist role. Previous studies suggest that this geographically variable niche divergence is generated by local processes in different contact zones. By varying the absolute and relative densities of Leptidea sinapis and Leptidea juvernica in large outdoor cages, we show that female mating success is unaffected by conspecific density, but strongly negatively affected by the density of the other species. Whereas 80% of the females mated when a conspecific couple was alone in a cage, less than 10% mated when the single couple shared the cage with five pairs of the other species. The heterospecific courtships can thus affect the population fitness, and for the species in the local minority, the suitability of a habitat is likely to depend on the presence or absence of the locally interacting species. If the local relative abundance of the different species depends on the colonization order, priority effects might determine the ecological roles of interacting species in this system.  相似文献   
68.
Nuclear restorer of fertility (Rf) genes suppress the effects of mitochondrial genes causing cytoplasmic male sterility (CMS), a condition in which plants fail to produce viable pollen. Rf genes, many of which encode RNA‐binding pentatricopeptide repeat (PPR) proteins, are applied in hybrid breeding to overcome CMS used to block self‐pollination of the seed parent. Here, we characterise the repertoire of restorer‐of‐fertility‐like (RFL) PPR genes in barley (Hordeum vulgare). We found 26 RFL genes in the reference genome (‘Morex’) and an additional 51 putative orthogroups (POGs) in a re‐sequencing data set from 262 barley genotypes and landraces. Whereas the sequences of some POGs are highly conserved across hundreds of barley accessions, the sequences of others are much more variable. High sequence variation strongly correlates with genomic location – the most variable genes are found in a cluster on chromosome 1H. A much higher likelihood of diversifying selection was found for genes within this cluster than for genes present as singlets. This work includes a comprehensive analysis of the patterns of intraspecific variation of RFL genes. The RFL sequences characterised in this study will be useful for the development of new markers for fertility restoration loci.  相似文献   
69.
万代兰属的属间界限划定及其亲缘关系重建是兰科分类系统中的难解之谜。该研究采用常规石蜡切片技术观察了珍稀濒危植物大花万代兰的一对深裂花粉团的形成机制、花药壁发育模式、小孢子发生及雄配子体发育等的胚胎学特征。结果表明:(1)大花万代兰早期的花药原基分化出一对侧生药室,每个药室的小孢子囊中央分化出一条在花药成熟时会降解的不育隔膜组织,形成两个不等深裂的花粉团。(2)发育完整的花药壁有5~9层,包括2~6层药室内壁,符合多层型花药壁发育类型;绒毡层细胞为单核,腺质型,在花药成熟时,表皮、中层和绒毡层皆降解,仅留下2~6层纤维性加厚的药室内壁。(3)小孢子母细胞经过连续型胞质分裂形成正四面体和左右对称的小孢子四分体,小孢子四分体继续保持在同一个胼胝质内,完成有丝分裂形成了2 细胞型的四合花粉;四合花粉两两紧密排列,且由于隔膜组织的降解,最终发育为一对深裂的花粉团。根据现有兰花花药发育资料,分析了大花万代兰花粉团发育的胚胎学特征的分类学意义,为万代兰属错综复杂的系统分类提供了新资料。  相似文献   
70.
The sociosexual environment animals experience through their life can shape the evolution of key life history traits, including longevity. Male–male competition, for instance, may influence the resources allocated to traits involved in male reproductive success. Here, I test whether lifelong exposure to a competitor male influences male investment in pre‐ and post‐copulatory sexual traits (calling effort and sperm quality) and how this affected the oxidative status and longevity of male field crickets (Gryllus bimaculatus). As expected, the visual exposure to a mating competitor promoted a higher calling effort in the male crickets but resulted in a decline in the haemolymph antioxidant content. The haemolymph antioxidant content negatively covaried with the antioxidant content of the sperm but interestingly, only when the males were exposed to a competitor. This suggests that when mating competition is high, males may prioritize sperm antioxidant protection against somatic maintenance. Finally, I provide evidence that male–male competition imposes additional costs to reproduction, as males exposed to a mating competitor lost a significant proportion of body antioxidant defences and body mass over time and in long term, had a reduced lifespan. Overall, this study strongly suggests that intrasexual competition may impose additional oxidative costs during reproduction for males, with negative consequences on lifespan. Moreover, the results highlight the role of oxidative stress as a physiological mechanism underlying the trade‐off between reproduction‐longevity and through which sexual selection may contribute to the evolution of senescence patterns.  相似文献   
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