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1.
DRIES KNAPEN MARTIN I. TAYLOR RONNY BLUST ERIK VERHEYEN 《Molecular ecology resources》2006,6(2):387-389
A total of seven polymorphic microsatellite loci from Gobio gobio were isolated and characterized. A preliminary population survey of 82 specimens from four populations, located in a downstream pollution gradient of cadmium and zinc, demonstrated the usefulness of these primers both in population genetic studies in general, as well as in evaluating the effects of anthropogenic pollution on genetic structure. Overall locus polymorphism ranged from two to 13 alleles. Observed heterozygosity per locus ranged from 0.39 to 0.73. 相似文献
2.
FRAUKE M. MUENZEL MATTHIAS SANETRA WALTER SALZBURGER AXEL MEYER 《Molecular ecology resources》2007,7(6):1048-1050
Eleven microsatellites were isolated from the vairone Leuciscus souffia (Risso 1826), an endangered fish that inhabits river systems in and around the Alps in Europe. The level of genetic diversity was assessed in 29 individuals of the subspecies L. s. souffia, and their variability was further estimated in seven individuals of a different subspecies, L. s. muticellus. Eight of these microsatellite loci were also applied to seven closely related cyprinid species. Availability of the reported microsatellite loci will facilitate the investigation of population genetic structure of these species with applications for the development of conservation strategies and phylogeographical approaches. 相似文献
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4.
Ten microsatellite loci were isolated from the earwig Labidura riparia (Pallas, 1773). The polymorphism of the loci was assessed in 24 individuals from one population. The number of alleles ranged from four to 11 alleles and observed and expected heterozygosities from 0.250 to 0.833 and from 0.551 to 0.861, respectively. 相似文献
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6.
SUMMARY 1. A sampler was developed that displaces surface water which is replaced with water from a sampling tube at a set depth.
2. The displacement sampler is inexpensive, easy to build, and is capable of collecting water at 7.5 I min−1 .
3. Phytoplankton photosynthesis was higher in water from the displacement sampler than in water collected with a Van-Dorn bottle. Subsequent experiments indicated this was due to inhibition caused by the Van-Dorn bottle. 相似文献
2. The displacement sampler is inexpensive, easy to build, and is capable of collecting water at 7.5 I min
3. Phytoplankton photosynthesis was higher in water from the displacement sampler than in water collected with a Van-Dorn bottle. Subsequent experiments indicated this was due to inhibition caused by the Van-Dorn bottle. 相似文献
7.
G. H. WALTER 《Ecological Entomology》1988,13(1):95-105
ABSTRACT.
- 1 Daily patterns of oviposition and host-feeding were examined in Coccophagus bartletti Annecke & Insley. Females began to host-feed and oviposit during the second or third day after emergence. Thereafter, both activities occurred regularly.
- 2 During long observation periods (5 h) most oviposition (93%) and host-feeding (90%) occurred within the first 3.5 h of wasps first encountering hosts. Experiments demonstrated that levels of activity were low for the rest of the day, and nocturnal oviposition occurred only if wasps had no alternative.
- 3 Dissection of female wasps that had been exposed to hosts, or withheld from them, for given periods of time, revealed that activity levels are governed by egg availability. Dispersal activity may also be influenced by the physiological state of the ovaries.
- 4 Production of a full complement of eggs (at 24±1°C (12 h L) and 18±1°C (12 h D)) took 48h or longer after host-feeding, and if wasps were withheld from hosts and provided with honey, the effects of egg resorption could be detected after about 10 days. Trends in oögenesis and oösorption in C. bartletti females seem not to conform with interpretations of oögenesis-oösorption cycles in other parasitoids.
- 5 The pattern of activity exhibited by C. bartletti females is not inflexible, but the major aspects mentioned above are species-specific. In general, information is needed about daily and hourly patterns of parasitoid oviposition and host-feeding before experiments are designed to test theories of parasitoid behaviour. Interpretation may otherwise rest on assumptions about their physiological condition.
8.
WALTER C. QUEVEDO JACOB DYCKMAN RUTH HALABAN GISELA E. MOELLMANN JANET M. COWAN THOMAS J. HOLSTEIN 《Pigment cell & melanoma research》1988,1(Z1):124-131
The BULT melanoma originated at Brown University as a spontaneous, small black nodule on the tail of an adult female mouse of the LT/Ch strain. Histological examination of a portion of the tumor indicated that it was intradermal and consisted predominantly of heavily melanized, ovoid to fusiform cells with melanin-laden macrophages scattered among them. The BULT melanoma has been maintained in LT/Ch mice for approximately 5 years by periodic transplantation, at first subcutaneously on the flanks and, more recently, intramuscularly in the hind legs. The shift in transplantation site was made following a marked decline in the growth of subcutaneous grafts. The transplants have retained the uniform deep-black melanization and general histology of the primary melanoma. Numerous melanosomes at all stages of development are found within the melanoma cells. DOPA-positive cytoplasmic vesicles are abundant. Occasional autophagic vacuoles containing clusters of melanosomes are also present. A few metastases from the transplanted melanoma have been observed in lymph nodes and on one occasion in the lungs. When grown in vitro, BULT melanoma cells do not require special growth promoting agents (e.g., TPA; cAMP) in order to proliferate. The BULT melanoma differs in one or more respects from each of the other three transplantable spontaneous mouse melanomas widely used in cancer research. In addition, it arose in a strain of mice characterized by the spontaneous death of melanocytes while the latter are engaged in synthesizing eumelanin within hair follicles. Karyotypic analysis of cultured cells showed a modal chromosome number of 68 with a range of 58–72 chromosomes. 相似文献
9.
Abstract.
- 1 Female eggs of Coccophagus atratus are deposited within the haemolymph of coccoid scale insects. Male eggs are deposited on to late larval and prepupal stages of parasitoids of scale insects, including conspecifics.
- 2 When presented with either one host type or a combination of both host types, female C.atratus deposit all their available eggs, assigning the appropriate sex egg to each host encountered. Brood sizes are not adjusted for different combinations of hosts.
- 3 Behavioural observations show that females do not move away from patches of hosts until all their eggs are laid, regardless of the host type.
- 4 Brood sex ratios varied with changes in the relative availability of hosts for males and hosts for females. When both host-types were present in equal numbers, male biased sex ratios resulted (mean ±SEM =0.71 ± 0.009) and when 70% of hosts provided were suitable for female eggs, mostly female-biased sex ratios resulted (mean ± SEM = 0.37±0.01).
- 5 Our results do not fit predictions based on the assumption that a sex ratio of 0.5 should be expected in C.atratus. Observed sex ratios indicate that the unusual life histories of these parasitoids need to be taken into account in explanations of their sex ratios.
10.
The described fossil testudinids from the Miocene of Africa are reviewed. Geochelone stromeri sp. nov . is described from Lower Pliocene (Langebaanweg) and Miocene (Namib) specimens. Kinixys erosa , an extant species, is reported from Songhor Hill. Chersina sp. is reported from Arrisdrift. Impregnochelys pachytectis gen. et sp. nov . is described from Rusinga Island, Kenya, and is unique in having the anterior shell opening orientated ventrally and in having struts on the internal surface of the neurals, but shares with Kinixys a unique epiplastron shape, a high number of axillary scutes and unique orientation of the head of the femur. 相似文献