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291.
Summary Reserpine, colchicine and Rb+ ions exerted specific effects on sexual behaviour and locomotor activity of the fruit fly. Neuroleptics and antidepressants were inactive. 相似文献
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293.
Summary While it is clear that juvenile hormone analogues disturb metamorphosis, there is some controversy about their effect on the activity of the corpus allatum in the course of metamorphosis. The present experiments showed that juvenile hormone analogues applied to eggs did not prevent inactivation of the corpus allatum at the onset of the last larval instar ofPyrrhocoris apterus. 相似文献
294.
The distribution of satellite cells (sc) in long-sarcomere muscle fibers from the carpopod extensor muscle of the crayfish (Astacus fluviatilis) has been studied electron-microscopically. The sc are spindle-shaped and are oriented parallel to the long axis of a fiber. The mean lengths of sc nuclei (17.00 microns) and that of myonuclei (18.35 microns) differ non-significantly. In older animals, the mean ratio of the number of sc nuclei to the total number of nuclei (sc nuclei + myonuclei) is 0.0716, 0.0848, and 0.034 for the tendon, central and shell segments, respectively. The corresponding values for younger animals are 0.158, 0.166, and 0.081. The mean numbers of sc nuclei per mm of a fiber are 94, 117, and 47 (older animals), and 164, 117, and 94 (younger animals) for the tendon, central and shell segments, respectively. The high incidence of sc per unit fiber length in crayfish may be related to the fact that crayfish muscle fibers have a much larger diameter than vertebrate muscle cells. 相似文献
295.
A. Čihák 《Cellular and molecular life sciences : CMLS》1977,33(1):16-17
Summary The insoluble form of phosphomonoesterase precipitated by means of Zn2+-ions was prepared from the partially purified extract of rat kidney. The freeze-dried preparation of the precipitated enzyme is highly active and is stable on heating at 100°C. 相似文献
296.
The recent report by Koprowski et al. that human T-cell lymphotropic retroviruses (HTLVs) may be involved in the development of multiple sclerosis (MS) has aroused much interest. The report was based largely on immunological evidence, using enzyme-linked immunosorbent assays (ELISAs) with viral antigens or disrupted virions. We have accordingly sought confirmation by screening sera and cerebrospinal fluid (CSF) samples from MS patients against cell lines infected respectively with adult T-cell leukaemia (ATL) virus (ATLV/HTLV-I) of Japanese cells (MT-1 and MT-2 lines), our own isolate from British black patients with ATL, the MoT cell line which produce HTLV-II, and our own T-cell line containing a local isolate of acquired immune deficiency syndrome (AIDS) virus (C-LAV/HTLV-III). We have failed to find antibodies against these retroviruses in the sera or CSF. Furthermore, neither virus could be isolated from the peripheral white blood cells of two MS patients. 相似文献
297.
E San Miguel Salán 《Experientia》1984,40(8):861-862
Samples from 4 populations of D. melanogaster were treated with formaldehyde by the larval feeding method, and induced lethality was scored. The results showed relevant differences among the populations analyzed. 相似文献
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Dose dependence of antigen binding to B and T lymphocytes 总被引:8,自引:0,他引:8