首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
会哭的鱼     
会哭的鱼,说的就是娃娃鱼,这让我想起40多年前第一次在自然环境中发现并捕捉到娃娃鱼的情景,至今还记忆犹新。 那是1960年的盛夏,我带领学生到河南西部伏牛山宝天曼一带的山区进行野生动物资源调查。天气非常炎热,使人透不过气来,刚刚到达目的地的第一天,吃过晚饭就和几位同学到住地近旁的一条小河沟洗澡乘凉。河水浅,清澈  相似文献   

2.
3.
4.
5.
6.
7.
8.
9.
黑脸琵鹭的觅食地在哪里?民以食为天,鸟为食而亡。弄清黑脸琵鹭的食物来源,对保护它们至关重要。  相似文献   

10.
Prospects for biopesticides for aphid control   总被引:1,自引:0,他引:1  
R. J. Milner 《BioControl》1997,42(1-2):227-239
Diseases form an important component of the natural enemy complex of aphids. The most common and obvious of these diseases are entomophthoran fungi such asErynia neoaphidis Remaudiere & Herbert,Entomophthora planchoniana Cornu,Zoophthora radicans (Brefeld) Batko andConidiobolus obscurus (Hall & Dunn) Remaudiere & Keller. The pest status of some aphids such as the pea aphid,Acyrthosiphon pisum (Harris), is considerably reduced by natural epizootics of fungal disease. However, disease may contribute little to practical control as it is mainly effective in high density populations when weather conditions are suitable. Introduction of exotic diseases for classical biological control is only rarely possible since most diseases, like their aphid hosts, are distributed world-wide. One exception was the successful introduction into Australia of a strain ofZ. radicans for control of spotted alfalfa aphid,Therioaphis trifolii (Monell) f.maculata in 1979. Attempts to manipulate entomophthoran fungi have had limited success because of problems with mass production, the fragility of the conidia and the need for suitably moist conditions. Hyphomycete fungi such asVerticillium lecanii (Zimm.) Viegas,Metarhizium anisopliae (Metsch.) Sorokin,Beauveria bassiana (Bals.) Vuill. andPaecilomyces spp. are more suitable for development as mycoinsecticides as they are cheap to mass produce and form stable conidia. “Vertalec?”, a formulation ofV. lecanii, has been sold in small quantities commercially in Britain and parts of Europe for many years and used mainly in glasshouses. Recently promising results have been obtained with use ofM. anisopliae for control of lettuce root aphid,Pemphigus bursarius (L.) in the UK. Laboratory studies on selected isolates ofB. bassiana andPaecilomyces spp. show a promising level of activity. Problems may occur with these species as they can kill aphid predators such as coccinelids. In addition, more research is needed on developing improved formulations which enable control to be achieved under low humidity conditions.  相似文献   

11.
12.
13.
14.
15.
Biobanks include biological samples and attached databases. Human biobanks occur in research, technological development and medical activities. Population genomics is highly dependent on the availability of large biobanks. Ethical issues must be considered: protecting the rights of those people whose samples or data are in biobanks (information, autonomy, confidentiality, protection of private life), assuring the non-commercial use of human body elements and the optimal use of samples and data. They balance other issues, such as protecting the rights of researchers and companies, allowing long-term use of biobanks while detailed information on future uses is not available. At the level of populations, the traditional form of informed consent is challenged. Other dimensions relate to the rights of a group as such, in addition to individual rights. Conditions of return of results and/or benefit to a population need to be defined. With 'large-scale biobanking' a marked trend in genomics, new societal dimensions appear, regarding communication, debate, regulation, societal control and valorization of such large biobanks. Exploring how genomics can help health sector biobanks to become more rationally constituted and exploited is an interesting perspective. For example, evaluating how genomic approaches can help in optimizing haematopoietic stem cell donor registries using new markers and high-throughput techniques to increase immunogenetic variability in such registries is a challenge currently being addressed. Ethical issues in such contexts are important, as not only individual decisions or projects are concerned, but also national policies in the international arena and organization of democratic debate about science, medicine and society.  相似文献   

16.
17.
The Amendments to the National Cancer Act of 1974 included a provision for a comprehensive review of the Federal policies and programs for medical research. This would appear to be a particularly timely review since many of the fundamental issues concerning the Government's role in biomedical research are presently in question. These issues include the rationale for public support for basic medical research, public expectations for returns on these investments, establishment of priorities among various research avenues, and a number of derivative as well as ethical questions. Since the professional and scientific communities have been historically successful in gaining public funds for research, a periodic opportunity for public review and consideration would appear to be highly desirable.  相似文献   

18.
Cell growth and differentiation in developing tissues are, at first impression, quite different endeavors from readjusting synaptic strength during activity-dependent synaptic plasticity in mature neurons. Nevertheless, it is becoming increasingly clear that these two distinct processes share multiple intracellular signaling events. How these common pathways result in cell division (during proliferation), large-scale cellular remodeling (during differentiation) or synapse-specific changes (during synaptic plasticity) is only starting to be elucidated. Here we review the latest findings on two prototypical examples of these shared mechanisms: the Ras-PI3K pathway and the intracellular signaling elicited by neural cell adhesion molecules interacting with growth factor receptors.  相似文献   

19.

Introduction

Rabies is a fatal acute viral disease of the central nervous system, which is a serious public health problem in Asian and African countries. Based on the clinical presentation, rabies can be classified into encephalitic (furious) or paralytic (numb) rabies. Early diagnosis of this disease is particularly important as rabies is invariably fatal if adequate post exposure prophylaxis is not administered immediately following the bite.

Methods

In this study, we carried out a quantitative proteomic analysis of the human brain tissue from cases of encephalitic and paralytic rabies along with normal human brain tissues using an 8-plex isobaric tags for relative and absolute quantification (iTRAQ) strategy.

Results and conclusion

We identified 402 proteins, of which a number of proteins were differentially expressed between encephalitic and paralytic rabies, including several novel proteins. The differentially expressed molecules included karyopherin alpha 4 (KPNA4), which was overexpressed only in paralytic rabies, calcium calmodulin dependent kinase 2 alpha (CAMK2A), which was upregulated in paralytic rabies group and glutamate ammonia ligase (GLUL), which was overexpressed in paralytic as well as encephalitic rabies. We validated two of the upregulated molecules, GLUL and CAMK2A, by dot blot assays and further validated CAMK2A by immunohistochemistry. These molecules need to be further investigated in body fluids such as cerebrospinal fluid in a larger cohort of rabies cases to determine their potential use as antemortem diagnostic biomarkers in rabies. This is the first study to systematically profile clinical subtypes of human rabies using an iTRAQ quantitative proteomics approach.  相似文献   

20.
Underwood WJ 《Lab animal》2005,34(8):29-32
As with other areas of animal research, ensuring the proper training and qualifications of the individuals working with agricultural animals for use in research, teaching, and testing is critical to both animal welfare and the successful outcome of the study or teaching exercise. The author provides guidance for the development of appropriate training programs for organizations that use agricultural animals in research.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号