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991.
M. Sick M. Ayasse J. Tengö W. Engels G. Lübke W. Francke 《Journal of Insect Behavior》1994,7(1):101-117
Nest invasion behavior was studied in six kleptoparasiticSphecodes species at four nesting sites of their respective social and solitary hosts.Sphecodes females preferred to enter unguarded nests. Nest intruding strategies observed in the differentSphecodes species did not depend on whether host species were solitary or social, as long as the nesting cycle of a social host was in the solitary stage (i.e., a single host female). Observation of intranidal behavior revealed thatSphecodes monilicornis females kill all host individuals within an usurped nest. They stay in the nest for several hours, laying eggs in adequately provisioned brood cells. Gas chromatography-mass spectrometry analyses of Dufour's gland secretions revealed species-specific compositions. Qualitative comparisons of whole patterns and quantitative comparisons considering the predominant hydrocarbons common to both host and parasite contradict the hypothesis of chemical mimetism, a mechanism supposed to permit parasite intrusion by qualitatively similar odor bouquets in host and parasite females. 相似文献
992.
Yu-Lin Ko Shih-Ann Chen Tang K. Tang Jiunn-Lee Lin Chern-En Chiang Jin-Jer Chen Ming-Sheng Teng Mau-Song Chang Wen-Pin Lien Cheng-Wen Wu 《Human genetics》1994,94(4):364-366
Recently the defective gene locus in seven Caucasian families with the Romano-Ward form of long QT syndrome (LQT) has been mapped to chromosome 11p. To understand the molecular basis of LQT in Chinese, a three-generation family was investigated. Fourteen family members were studied and five individuals were diagnosed to be affected, according to electrocardiographic criteria. Two genomic DNA probes (c-Ha-ras-3-HVR and insulin-5-HVR) and one tetranucleotide repeat polymorphism (THZ) derived from chromosome 11p15.5 loci and previously demonstrated to be closely linked to LQT were used as probes to analyze this family. A lod score of less than -2 was noted for all three polymorphisms. Our data show that there was no evidence of linkage between these three loci and the gene for LQT in this studied family. We believe that this result provides additional evidence for genetic heterogeneity of LQT. 相似文献
993.
作者用高效液相层析(HPLC)法测定了汉、回、维吾尔(维)、哈萨克(哈)族新生儿胎儿血红蛋白(HbF)中~Gγ/~Aγ、~Aγ~I/~Aγ~T比值,共372例,其中汉族和回族各102例、维族99例、哈族69例。%~Gγ(~Gγ/~Aγ)均值:汉、回、维、哈族分别为66.83%、68.33%、70.44%和69.70%。低~Gγ者(<50%)4例:其中回族3例、哈族1例。高~Gγ者(>80%)25例:汉和哈族各5例、回族4例,维族11例。发现~Aγ~T杂合子99例分别为:汉21例、回23例、维26例、哈族29例。4个民族各发现1例~Aγ~T纯合子。%~Aγ~I(~Aγ~I/~Aγ~T)均值:汉56.83%、回55.58%、维50.94%、哈54.68%。~Aγ~T基因频率依次为0.113、0.123、0.141及0.225。两例比值异常者(1例维族高~Gγ85.42%、~Aγ~T杂合体。1例回族低~Gγ43.4%,~Aγ~I纯合体)经γ基因图谱分析,确定高~Gγ值者γ珠蛋白基因型为-~Gγ-~(AG)γ-~Aγ~T(~Aγ~I)-/-~Gγ-~Aγ~I,(~Aγ~T)-;低~Gγ值者为-~(GA)γ~I-/-~Gγ-~Aγ~I-。 相似文献
994.
人蚤及猫栉头蚤是家庭内常见的两种跳蚤。它们的分布遍及全世界。关于它们的调查和研究,世界各地曾有很多报告。作者在北京(1950—51 相似文献
995.
Xi‐Ping Dong Kelly Vargas John A. Cunningham Huaqiao Zhang Teng Liu Fang Chen Jianbo Liu Stefan Bengtson Philip C. J. Donoghue 《Palaeontology》2016,59(3):387-407
Fossilized embryos afford direct insight into the pattern of development in extinct organisms, providing unique tests of hypotheses of developmental evolution based in comparative embryology. However, these fossils can only be effective in this role if their embryology and phylogenetic affinities are well constrained. We elucidate and interpret the development of Olivooides from embryonic and adult stages and use these data to discriminate among competing interpretations of their anatomy and affinity. The embryology of Olivooides is principally characterized by the development of an ornamented periderm that initially forms externally and is subsequently formed internally, released at the aperture, facilitating the direct development of the embryo into an adult theca. Internal anatomy is known only from embryonic stages, revealing two internal tissue layers, the innermost of which is developed into three transversally arranged walls that partly divide the lumen into an abapertural region, interpreted as the gut of a polyp, and an adapertural region that includes structures that resemble the peridermal teeth of coronate scyphozoans. The anatomy and pattern of development exhibited by Olivooides appears common to the other known genus of olivooid, Quadrapyrgites, which differs in its tetraradial, as opposed to pentaradial symmetry. We reject previous interpretations of the olivooids as cycloneuralians, principally on the grounds that they lack a through gut and introvert, in embryo and adult. Instead we consider the affinities of the olivooids among medusozoan cnidarians; our phylogenetic analysis supports their classification as total‐group Coronata, within crown‐Scyphozoa. Olivooides and Quadrapyrgites evidence a broader range of life history strategies and bodyplan symmetry than is otherwise commonly represented in extant Scyphozoa specifically, and Cnidaria more generally. 相似文献
996.
997.
Yuan Zhang Xiaohuan Yuan Wenjun Teng Chao Chen Juying Wu 《Plant Molecular Biology Reporter》2016,34(6):1181-1192
Pennisetum species are widely used as ornamental grasses and may be a valuable genetic resource for their breeding to broaden its genetic basis. At present, new ornamental Pennisetum cultivars are primarily bred via somaclone, which increases the number of variants. It is difficult to estimate whether the suspected variants are authentic in genetic features by morphological traits because of their many limitations. Moreover, although the phylogenetic classification of the Pennisetum genus has been approved in some morphological and cytological studies, genetic evidence is lacking. In the present study, we developed 15 specific simple sequence repeat (SSR) markers with a large amount of polymorphisms and strong distinguishing abilities for Pennisetum ornamental grasses using magnetic bead enrichment. These markers, together with the other 11 reported polymorphic SSRs, were further used for the identification of a broad collection of 55 Pennisetum samples, including nine original taxa and 46 suspected variants. After comparing the genetic characteristics between each variant and its corresponding original taxon, we verified 20 suspected variants that possess the potential to become new, commercially desirable cultivars. The nine original taxa and the 20 verified variants were identified based on the polymorphisms of six core loci, and unique molecular identities with 15 denary digits for each taxon were further established. The rationality of the traditional phylogenetic classification system of the Pennisetum genus was further verified using 147 polymorphic alleles. The present study promotes the protection, registration, breeding, and international communication of Pennisetum ornamental grasses. 相似文献
998.
999.
1000.