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1.
C. D. Schenkel T. Kamber F. Schaffner A. Mathis C. Silaghi 《Medical and veterinary entomology》2019,33(3):345-351
Invasive Aedes mosquito species (Diptera: Culicidae) are of public health concern in Europe because they are either recognized or potential vectors of pathogens. Loop‐mediated isothermal amplification (LAMP) is a rapid and simple method for amplifying DNA with high specificity and efficiency, with the technique having potential for application in the field, including in high‐throughput format. Specific LAMP assays based on rDNA internal transcribed spacers 1 or 2 sequences, considering intraspecies variability at these loci, were developed for Aedes aegypti, Aedes albopictus, Aedes japonicus, Aedes koreicus and the indigenous Aedes geniculatus. No such assays could be developed for Aedes atropalpus and Aedes triseriatus because both loci were too short to serve as target. The assays rely on the clearly visible colour change from violet to sky blue after successful amplification. Sensitivity of egg detection was confirmed with ratios of up to one mosquito egg in 99 other eggs. Simple sample preparation of adults or eggs by mechanical homogenization in water required an additional heat treatment or centrifugation step to avoid non‐specific colour changes. Thus, further technical improvements are needed to render these assays truly field‐applicable, which would greatly facilitate surveillance of these invasive mosquito species and allow for prompt implementation of control measures. 相似文献
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Bird A.F. and Stynes B.A. 1981. The life cycle of Anguina agrostis: Development in the host plant. Internationaljournal for Parasitology11: 431–440. The growth and development of the infective second stage “dauer” larvae (DL2) of Anguina agrostis into adults have been followed under field conditions in rye grass (Lolium rigidum). Three moults were observed to occur during the parasitic phase of development. From the third (second parasitic) moult onwards, there was much more variability in the size of the female nematodes than in the males and sexual dimorphism became very pronounced. The transition from the DL2 to the second stage parasitic larva (PL2) is marked by the disappearance of the numerous lipid storage granules which are characteristic of the DL2, and the development in the PL2 of an intestine which becomes more pronounced in each succeeding stage, particularly in the adult female. Anguina agrostis is unusual among parasitic nematodes in that the DL2 has the thickest cuticle of all stages, including adults. The L4 and adult males have thicker cuticles than the females at the same stages of development. Moulting appears to involve resorption of the innermost basal zone of the shed cuticle as well as morphological and chemical changes to the epicuticle. 相似文献
4.
《Molecular & cellular proteomics : MCP》2020,19(11):1767-1776
Highlights
- •N-glycan patterns are distinct in pediatric and adult urine.
- •Sex differences of N-glycans are much larger in adults.
- •Pediatric urine has almost no sex differences in N-glycan levels.
- •In adults, the majority of N-glycans were more abundant in males.
5.
All the developmental stages of Chrysoperla carnea (Stephens) were treated with fipronil using different modes of exposure under laboratory conditions. Eggs were dipped in an aqueous range of concentrations and no effects were recorded, except at the highest concentration. Pupae treated topically on the silk cocoon moulted to healthy adults, without any deleterious effects on their reproduction. In contrast, larvae and adults were killed by the compound, irrespective of the mode of treatment, even at rates below the maximum field recommended rate in Spain (30 g c.p./ha). Sublethal concentrations of fipronil did not affect the fecundity or fertility of survivors. We conclude that fipronil is very toxic under laboratory conditions to this predatory lacewing. 相似文献
6.
Using ruthenium red as a macromolecule, endocytosis was demonstrated in the plerocercoid of Ligula intestinalis and adult Schistocephalus solidus. Uptake, transport across the tegument, and exocytosis across the basal plasma membrane occurred within 6 min. The types of vesicles in the tegument of L. intestinalis are redescribed and their former classification is modified. The vertical and longitudinal distribution of pinosomes in the tegument of adult S. solidus and L. intestinalis plerocercoids were determined. The possible role of macromolecular uptake in the economy of pseudophyllidean tapeworms is discussed with particular reference to growth and defence of an unencysted larval stage in the tissues of the intermediate host. 相似文献
7.
Seasonal changes in the reproductive and life‐history traits of Chrysomela populi L. were investigated in Shobara (34°52′N, 133°01′E), Japan, in 2004 and 2005. Larvae were hatched and reared under natural photoperiod and temperature in 8 different periods between late April and early September in 2004. The incidence of adult diapause increased with progression of the season in 2004. The critical timing of diapause induction, as defined by 50% of females entering diapause, was estimated to occur between late July and early August. No effects of season on the survival rate from hatching to adult emergence, percentage ovipositing females and percentage females that deposited viable eggs were clearly detected. Adult weight at emergence fluctuated seasonally, which was probably caused by air temperature. No effect of season on the oviposition period was observed among females that averted diapause. Females that entered diapause in 2004 started oviposition from the first day of May in 2005. Reproductive output was significantly greater in diapause females than in non‐diapause females. This increase in the reproductive output of diapause females was caused by elongation of the oviposition period and consequently by enlargement of the number of egg clutches deposited. These results suggest that the seasonal timing of diapause induction in females of C. populi would be affected by various risks and benefits to reproduction and survival. 相似文献
8.
Location and functional characterization of the right atrioventricular pacemaker ring in the adult avian heart 下载免费PDF全文
Previous histological studies showed that in addition to a sinus node, an atrioventricular (AV) node, an AV bundle, left and right bundle branches, birds also possess a right AV‐Purkinje ring that is located in the atrial sheet of the right muscular AV‐valve along all its base length. The functionality of the AV‐Purkinje ring is unknown. In this work, we studied the topology of pacemaker myocytes in the atrial side of the isolated chicken spontaneously contracting right muscular AV‐valve using the method of microelectrode mapping of action potentials. We show that AV‐cells having the ability to show pacemaking reside in the right muscular AV‐valve. Pacemaker action potentials were exclusively recorded close to the base of the valve along its whole length from dorsal to the ventral attachment to the interventricular septum. These action potentials have much slower rate of depolarization, lower amplitude, and higher diastolic depolarization than action potentials of Purkinje (conducting) cells. We conclude the right AV‐valve has a ring bundle of pacemaker cells (but not Purkinje cells) in the adult chicken heart. J. Morphol. 277:363–369, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
9.
TOSHIAKI SHIMIZU 《Invertebrate reproduction & development.》2013,57(3):221-224
Summary Development of the upper vas deferens and seminal vesicle, and the ecdysteroid titers of the cabbage armyworm (Mamestra brassicae) during pharate adult stage were investigated to provide evidence of endogenous control of the sperm movement through the reproductive tract. Apparently, development of the upper vas deferens is initiated when ecdysteroid titers increase after pupation and continues until eclosion. Sperm movement correlates with the decrease of ecdysteroid titers. When ecdysteroid titers remained at low levels, sperm release from the testis was observed one day before eclosion. 相似文献
10.
Stem cells: is there a future in plastics? 总被引:3,自引:0,他引:3
Margaret A. Goodell 《Current opinion in cell biology》2001,13(6):662-665
The concept that ostensibly tissue-specific stem cells can give rise to cells of heterologous lineages has gained support from studies using purified hematopoietic stem cells and sensitive donor-cell tracking methods. The ability to exploit these findings in clinical settings will probably depend on new insights into the mechanisms by which such stem cells or their progeny migrate to sites of organ damage and differentiate to cell types competent to participate in tissue regeneration. 相似文献