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31.
32.
Biological weapons 总被引:1,自引:0,他引:1
Tegnell A Van Loock F Baka A Wallyn S Hendriks J Werner A Gouvras G 《Cellular and molecular life sciences : CMLS》2006,63(19-20):2223-2228
Adequate public health preparedness for bioterrorism includes the elaboration of an agreed list of biological and chemical agents that might be used in an attack or as threats of deliberate release. In the absence of counterterrorism intelligence information, public health authorities can also base their preparedness on the agents for which the national health structures would be most vulnerable. This article aims to describe a logical method and the characteristics of the variables to be brought in a weighing process to reach a priority list for preparedness. The European Union, in the aftermath of the anthrax events of October 2001 in the United States, set up a task force of experts from multiple member states to elaborate and implement a health security programme. One of the first tasks of this task force was to come up with a list of priority threats. The model, presented here, allows Web-based updates for newly identified agents and for the changes occurring in preventive measures for agents already listed. The same model also allows the identification of priority protection action areas. 相似文献
33.
Cell surface receptors bind ligands expressed on other cells (in trans) in order to communicate with neighboring cells. However, an increasing number of cell surface receptors are found to also interact with ligands expressed on the same cell (in cis). These observations raise questions regarding the biological role of such cis interactions. Specifically, it is important to know whether cis and trans binding have distinct functional effects and, if so, how a single cell discriminates between interactions in cis versus trans. Further, what are the structural features that allow certain cell surface receptors to engage ligand both on the same as well as on an apposed cell membrane? Here, we summarize known examples of receptors that display cis–trans binding and discuss the emerging diversity of biological roles played by these unconventional two-way interactions, along with their structural basis. 相似文献
34.
A new approach to isotonic agglomerative hierarchical clustering 总被引:1,自引:1,他引:0
Hierarchical clustering methods must be isotonic for the construction of ultrametric. We present a general strategy to widen
the class of isotonic methods implemented by agglomerative algorithms. At each step of the agglomeration we allow one of several
admissible pairs to be chosen. Then under mild assumptions an appropriate definition of admissibility guarantees isotony.
Moreover we consider the use of the new methods to compute locally optimal ultrametrics. Two examples demonstrate the ability
to define new agglomerative methods superior to their traditional competitors. 相似文献
35.
Werner Brückner 《Cellular and molecular life sciences : CMLS》1945,1(5):157-158
Ohne Zusammenfassung 相似文献
36.
Werner Kuhn 《Cellular and molecular life sciences : CMLS》1948,4(1):23-24
Summary A thermodynamic consideration shows that SiO2 may be reduced to Si by hydrogen at the temperatures present in the earth's interior. The reaction can be expected to involve a rapid change of viscosity with depth inside the earth, required for the explanation of the seismic discontinuity at 2,900 km. 相似文献
37.
New concepts in regulation and function of the insulin-like growth factors: implications for understanding normal growth and neoplasia 总被引:12,自引:1,他引:11
The insulin-like growth factors (IGFs) are a ubiquitous family of growth factors, binding proteins and receptors that are involved in normal growth and development. They are also implicated in numerous pathological states, including malignancy. IGF-II is a commonly expressed growth factor in many tumors and may enhance tumor growth, acting via the overexpressed IGF-I receptor, a cell-surface tyrosine kinase receptor. The IGF-I receptor may be overexpressed due to mutations in tumor suppression gene products such as p53 and WT-1 or growth factors such as bFGF and PDGF. Thus, this family of growth factors, especially the IGF-I receptor, may present an excellent target for new therapeutic agents in the treatment of cancer and other disorders of excessive cellular proliferation. 相似文献
38.
Zusammenfassung Die Hemmung der Phenylpyruvat- undp-Hydroxyphenylpyruvat-Oxydasen durch Chelat-Wirkstoffe wurde offenbar durch die Bildung eines Enzym-Wirkstoff-Komplexes verursacht, der bei Behandlung mit Kationen oder mit Sephadex trennbar ist. Die Reinigung des Enzyms führt zur Kupferanreicherung des Präparates, welches eine scheinbar funktionelle Einheit mit dem Enzym bildet.
This work was supported in part by Research Grant No. MH-02278 from the National Institute of Mental Health, U.S.P.H.S.
We wish to thank Dr.W. A. Bulen for helpful discussions about the mechanism of inhibition, and Dr.M. D. Armstrong for his encouragement during this project. 相似文献
This work was supported in part by Research Grant No. MH-02278 from the National Institute of Mental Health, U.S.P.H.S.
We wish to thank Dr.W. A. Bulen for helpful discussions about the mechanism of inhibition, and Dr.M. D. Armstrong for his encouragement during this project. 相似文献
39.
G. Werner 《Cellular and molecular life sciences : CMLS》1961,17(2):95-96
Zusammenfassung Aus den bisher veröffentlichten experimentellen Befunden über presynaptische, für die neuromuskuläre Erregungsübertragung massgeblich erscheinende Vorgänge wird geschlossen, dass die Förderung der Erregungsübertragung in direkter Beziehung zur Grösse des Aktionspotentials in den motorischen Nervenendigungen steht, während die Frequenz der spontanen Miniaturentladungen an sich kein eindeutiges Mass für die Intensität des Übertragungsvorganges von Nervimpulsen zum Muskel darstellt. 相似文献
40.
Summary Anti-toxoplasma antibodies administered passively to mice may lead to suppression or enhancement (reported for the first time with Protozoan parasites) of subsequent antibody response when these animals are later infected withToxoplasma gondii. The outcome is dependent on infecting strain of Toxoplasma and the antigen-antibody ratio. 相似文献