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111.
Summary Lentin binds specifically to sea urchin embryo chromatin. This binding is saturable and inhibited by -methylmannose. Scatchard plot analysis of the binding reaction suggests a single binding site.  相似文献   
112.
Summary It is shown that the average quasi-valence numbers of antibiotics inhibiting protein synthesis are well defined and lie in the region of average quasi-valence numbers of amino acids, while the average quasi-valence numbers of antibiotics inhibiting DNA or RNA synthesis have higher values. Possible explanations of these findings and their implications on the design and selection of antibiotics are discussed.  相似文献   
113.
Summary Sex differences of high significance in the marrow weight relative to femur volume, as well as to body weight, were found in adult rats. A positive significant correlation was found between the femur volume and the marrow volume in both sexes, while a negative significant correlation between femur density and the marrow content (mg/mm3) exists only in male rats.  相似文献   
114.
Summary It is found that the average quasi-valence numbers of alkylating cytostatics lie in the region of potential carcinogens, while the average quasi-valence numbers of antimetabolites predominantly cover the region of noncarcinogens. Implications of this finding on the design of new drugs are discussed.  相似文献   
115.
Summary A correlation between the carcinogenicity of organic substances and their UV-absorption characteristics has been established. It is found that chemical carcinogens have absorption maxima in the wavelength region of 206–248 nm. On the basis of revealed correlation, a mechanism of chemical carcinogenesis is proposed.  相似文献   
116.
Summary The correlation between the average quasi-valence number and carcinogenicity of organic compounds has been established and discussed.  相似文献   
117.
关于一类非线性波动方程的准确周期解   总被引:5,自引:2,他引:5  
应用Jacobi椭圆函数展开法求得了两种非线性波动方程的准确周期解,而且这些周期解在一定条件下可以退化为包络孤立波解。  相似文献   
118.
Zusammenfassung Das zerebrale Serotonin unterliegt im Verlaufe eines emotionellen Stress bedeutenden quantitativen Veränderungen. Bei Wildhasen, welche 14 Tage lang Schreckzeichen ausgesetzt waren, vermehrte sich die Menge des Serotonins und erreichte ihr Maximum am 7. Tag. Nachher sinkt die Menge unter den Normalwert, um am Ende der zweiten Woche wieder anzusteigen, wobei sie unter dem Normalwert bleibt.  相似文献   
119.
Brown WM  Cronk L  Grochow K  Jacobson A  Liu CK  Popović Z  Trivers R 《Nature》2005,438(7071):1148-1150
Dance is believed to be important in the courtship of a variety of species, including humans, but nothing is known about what dance reveals about the underlying phenotypic--or genotypic--quality of the dancer. One measure of quality in evolutionary studies is the degree of bodily symmetry (fluctuating asymmetry, FA), because it measures developmental stability. Does dance quality reveal FA to the observer and is the effect stronger for male dancers than female? To answer these questions, we chose a population that has been measured twice for FA since 1996 (ref. 9) in a society (Jamaican) in which dancing is important in the lives of both sexes. Motion-capture cameras created controlled stimuli (in the form of videos) that isolated dance movements from all other aspects of visual appearance (including FA), and the same population evaluated these videos for dancing ability. Here we report that there are strong positive associations between symmetry and dancing ability, and these associations were stronger in men than in women. In addition, women rate dances by symmetrical men relatively more positively than do men, and more-symmetrical men value symmetry in women dancers more than do less-symmetrical men. In summary, dance in Jamaica seems to show evidence of sexual selection and to reveal important information about the dancer.  相似文献   
120.
Human cytomegalovirus (HCMV) infection or reactivation is a cause of morbidity and mortality in immunocompromised individuals. In immunocompetent individuals, in contrast, HCMV is successfully controlled by specific CD8 and CD4 T cells. Knowledge of CD8 and CD4 T cell epitopes from HCMV and their immunodominant features is crucial for the generation of epitope-specific T cells for adoptive immunotherapy and for the development of a peptide-based HCMV vaccine. Therefore, we investigated the natural frequencies of a large number of CD8 and CD4 T cell epitopes, including 10 novel ones. We determined several epitopes as immunodominant. Surprisingly, no clear hierarchies were found for CD8 T cell epitopes, indicating codominance. These results will be valuable for adoptive transfer strategies and support initiatives towards development of a peptide-based HCMV vaccine.Received 12 August 2004; received after revision 24 September 2004; accepted 29 October 2004 These authors contributed equally to this work.  相似文献   
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