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1.
拟寄生蜂的寄主标记研究进展   总被引:4,自引:1,他引:3  
李国清 《昆虫学报》2006,49(3):504-512
拟寄生蜂常借助寄主标记信息素 (host marking pheromone, HMP) 来辨别已寄生寄主和健康寄主,避免过寄生和多寄生,减少后代的种内和种间竞争。寄主标记有外部标记、内部标记和“容器”及区域标记3种方式。HMP来源于拟寄生蜂的杜氏腺、毒腺、输卵管、卵巢、卵或咽侧体,由触角或产卵器感受。目前已鉴定出几种拟寄生蜂的HMP,多数为饱和与不饱和烃类的混合物,但卡氏盾痣细蜂Dendrocerus carpenteri的HMP是保幼激素。拟寄生蜂对寄主标记的反应受HMP持效期,拟寄生蜂内部状况如载卵量、年龄、经验和学习,及外部条件如拟寄生蜂和健康寄主种群密度以及寄主种类的影响。本文还讨论了HMP研究的理论和实际意义。  相似文献   

2.
A new European legislation on herbal medicinal products (HMPs) was developed, in order to harmonise the use of HMPs in the 28 member states of the European Union, according to Directive 2004/24/EC which amended the basic legislation laid down in Directive 2001/83/EC. The objective of this legislation was to ensure the future existence of such products and to consider particular characteristics during the assessment of their quality, efficacy and safety, having defined two categories for herbal medicines: (a) well-established use HMPs, which can be granted a marketing authorisation; and (b) traditional herbal medicinal products which can be granted a registration based on their long-standing safe and efficient use. The Committee on Herbal Medicinal Products was established at the European Medicines Agency in 2004, in order mainly to provide community monographs and list entries on herbal substances and preparations. 120 monographs have been published since then, which offer a scientific and regulatory standard for their safety and efficacy, during their use as medicinal products. The HMPs can be placed in the market after quality, efficacy, and safety have been assessed according to the provisions of the legislation (Directive 2004/24/EC and Directive 2001/83/EC), with adequate labeling information to patients and health care professionals, distinguishing them from other product categories containing herbs like: foods, food supplements, medical devices and cosmetics.  相似文献   

3.

Background  

The rapid publication of important research in the biomedical literature makes it increasingly difficult for researchers to keep current with significant work in their area of interest.  相似文献   

4.

Background  

The existing dogma that the former term ovarian "germinal epithelium" resulted from a mistaken belief that it could give rise to new germ cells is now strongly challenged.  相似文献   

5.

Background  

Although the neural mechanism of chronic fatigue syndrome has been investigated by a number of researchers, it remains poorly understood.  相似文献   

6.

Background  

Few microarrays have been quantitatively calibrated to identify optimal hybridization conditions because it is difficult to precisely determine the hybridization characteristics of a microarray using biologically variable cDNA samples.  相似文献   

7.

Background  

Serum follicle stimulating hormone (FSH) levels are used clinically to evaluate infertility, pituitary and gonadal disorders. With increased frequency of research collaborations across institutions, it is essential that inter-laboratory validation is addressed.  相似文献   

8.

Background  

With the explosion in data generated using microarray technology by different investigators working on similar experiments, it is of interest to combine results across multiple studies.  相似文献   

9.

Introduction  

As part of a clinical proteomics programme focused on diabetes and its complications, it was our goal to investigate the proteome of plasma in order to find improved candidate biomarkers to predict diabetic nephropathy.  相似文献   

10.

Background  

The evolution of genomic imprinting, the parental-origin specific expression of genes, is the subject of much debate. There are several theories to account for how the mechanism evolved including the hypothesis that it was driven by the evolution of X-inactivation, or that it arose from an ancestrally imprinted chromosome.  相似文献   

11.
12.

Background  

As high-throughput technologies rapidly generate genome-scale data, it becomes increasingly important to visually integrate these data so that specific hypotheses can be formulated and tested.  相似文献   

13.

Background  

The stress response is a critical factor in the training of equine athletes; it is important for performance and for protection of the animal against physio-pathological disorders.  相似文献   

14.

Background  

Vibrio cholerae gains natural competence upon growth on chitin. This allows the organism to take up free DNA from the environment and to incorporate it into its genome by homologous recombination.  相似文献   

15.

Background  

Routine antibiotic prophylaxis following snakebite is not recommended but evidence suggests that it may be common practice in Zimbabwe. This study set out to determine and describe the extent of this practice at Parirenyatwa Hospital, a large teaching hospital in Zimbabwe  相似文献   

16.

Background  

Background: Cytolethal distending toxin (CDT) is one of the well-characterized virulence factors of Campylobacter jejuni, but it is unknown how CDT becomes surface-exposed or is released from the bacterium to the surrounding environment.  相似文献   

17.

Background  

B-RAF kinase plays an important role both in tumour induction and maintenance in several cancers and it is an attractive new drug target. However, the structural basis of the B-RAF activation is still not well understood.  相似文献   

18.

Background  

Soybeans play a prominent role in allergologic research due to the high incidence of allergic reactions. For detailed studies on specific proteins it is necessary to have access to a large amount of pure substance.  相似文献   

19.

Background  

High-throughput sequencing makes it possible to rapidly obtain thousands of 16S rDNA sequences from environmental samples. Bioinformatic tools for the analyses of large 16S rDNA sequence databases are needed to comprehensively describe and compare these datasets.  相似文献   

20.

Background  

The availability of biomedical literature in electronic format has made it possible to implement automatic text processing methods to expose implicit relationships among different documents, and more importantly, the functional relationships among the molecules and processes that these documents describe.  相似文献   

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