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101.
Douglas H. Taylor Kraig Adler 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1978,124(4):357-361
Summary Tiger salamanders (Ambystoma tigrinum) trained to orient in a particular compass direction under the sun fail to orient in the trained direction if they are (i) eyeless and simultaneously have the brain covered with opaque plastic or are (ii) eyeless and pinealectomized (Fig. 1–2, Table 1). Salamanders with either the eyes or the pineal intact and unobstructed continue to orient in the trained direction. These data strongly support the hypothesis that the pineal body is an effective extraocular photoreceptor (EOP) for compass orientation in tiger salamanders.We thank M.P. Farrell for developing computer programs for data analysis. B. Bailey and R. Walton helped conduct tests. Financial support was provided for separate phases of this research by a Biomedical Science Support Grant (NIH FR 07033-05) and NSFgrants GB-30647 and BMS 75-18693 to K. Adler and an Indiana Academy of Science Research Grant, a postdoctoral fellowship (NSF GU-2058), a Miami University Research Grant and an NSF grant (GB-41102) to D.H. Taylor. 相似文献
102.
The a priori probability of noticeable linkage among all conceivable experiments of the size reported by Mendel cannot reasonably be taken as greater than 24-36 per cent; and therefore, the frequently heard opinion that his chances of encountering linkage were high, approaching 99-4 per cent, appears to be mistaken. 相似文献
103.
William r. Anderson Willi Frick G.Doyle Daves Douglas F. Barofsky Isomaro Yamaguchi Ding Chang Karl Folkers Sune Rosell 《Biochemical and biophysical research communications》1977,78(1):372-376
Mass spectra of underivatized hexa- and heptapeptide amides related to Substance P have been obtained with a conventional electron ionization mass spectrometer using sample vaporization from a tungsten wire by the technique of rapid heating, proton transfer ionization using ammonia, and photoplate recording of spectra. These spectra exhibit little evidence of sample pyrolysis and are readily interpreted to yield amino acid sequences. 相似文献
104.
Microsporidian spore polypeptides separated with sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) can be used to identify isolates of microsporidia. The spore polypeptides separated with SDS/PAGE provided unique, reproducible electrophoretic profiles which were not influenced by host species or the temperature at which the host larvae were maintained for development. Furthermore, host proteins were not detected in electrophoretic profiles of the spore polypeptides. Spore mixtures of two microsporidian species can be detected when the spore polypeptides of either or both species have been previously separated with SDS/PAGE. 相似文献
105.
40 pelvic preparations of rabbits (oryctolagus cuniculus) were bilaterally studied by dissection under the stereomicroscope and angiography. The arterial pattern of the pelvis, i.e. origin and branching of the umbilical, urogenital and internal pudendal arteries (visceral branches), is described. The main characteristics observed are as follows: (1) The umbilical artery is permeable in adults and gives origin to the cranial vesical artery and a caudal branch that irrigates the pelvic urogenital organs and, eventually, the rectum, with six patterns of branching in both sexes. (2) Usually, the urogenital artery is the continuation of the visceral branch of the internal iliac artery. In 1 animal, unilaterally, it arises from the median sacral artery. In 12 animals (6 bilaterally and 6 unilaterally) the urogenital artery is absent. When present, it forms two branches, a cranial and a caudal one, that irrigate of the urogenital organs in both sexes. (3) The internal pudendal artery is the direct continuation of the internal iliac artery and gives to rise to some visceral branches that irrigate the penis, bulbourethral gland and rectum (with six patterns of branching) in males, and the vagina, clitoris and rectum (with three patterns of branching) in females. 相似文献
106.
Existing techniques for analysing the organization of behavioural events are discussed. Cluster analysis, mutual replaceability, ‘melody’ detection and Markov analyses are examined in order to discover the validity and usefulness of the concepts searched for by each technique, and the mathematical and statistical background of the techniques is scrutinized. Some new techniques, designed to search for and detect possible important sequential organization patterns, are described in the light of the previous criticisms. Of these techniques, the Pre-post-state Histogram (PPSH)—a multi-order Markov graphical analysis—would appear to be the most important for future work, especially when used in conjunction with the other techniques described. 相似文献
107.
Organic matter sedimented within salt deposits from the Carboniferous Perm epoch has been investigated for hydrocarbons by gas-liquid-chromatography, mass spectrometry, and spectropolarimetry. Main constituents were made of aliphatic and olefinic hydrocarbons which retained a considerable part of their optical activity thus resisting complete racemization over 250 mio years. 相似文献
108.
Summary Chorionic villi from first trimester and term human placentas have been incubated in vitro and shown to release the lysosomal enzymes, -hexosaminidase, -glucosidase and -gluctlronidase. There was negligible release of the cytoplasmic enzyme, lactate dehydrogenase, under the same conditions. The first trimester villi released proportionally more of their lysosomal enzyme content than did the term villi. Extracellular levels of -hexosaminidase were raised and those of -glucosidase and, -glucuronidase were lowered when tissue was incubated with 1 M colchicine, suggesting that microtubules are involved in the control of lysosomal enzyme release from placental villi. 相似文献
109.
Virus-induced interferon production by human macrophages. 总被引:4,自引:0,他引:4
N J Roberts R G Douglas R M Simons M E Diamond 《Journal of immunology (Baltimore, Md. : 1950)》1979,123(1):365-369
110.