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Larval Typhlotriton spelaeus collected from five caves in Pulaski Co., Missouri, were kept as larvae or induced to transform in darkness or continuous fluorescent illumination. Larvae maintained in darkness for 215 and 279 days had smaller eyes, smaller rod inner and outer segments, and fewer metaphase figures in the germinative zone of the neural retina than comparable larvae maintained in light (258 lux). Except for visual cell size, differences were small and for each characteristic exceptions were observed. One larva kept in light showed early retinal degeneration comparable to that in transformed adults to T. spelaeus. All larvae exhibited optomotor behavior both before and after the experiment. Among animals induced to transform by L-thyroxin and maintained in darkness 111 to 366 days, visual cell and pigment epithelium degeneration was more extensive and more frequent than in animals kept for the same length of time in light (237-298 lux). In darkness the frequency of animals with retinal degeneration increased between 111 and 366 days. In light some animals exhibited pigment epithelium reduction with normal visual cells, and others had free, pigmented cells in the subretinal space. These effects were not comparable to degeneration in darkness. Eyelids covered the eyes of only a few animals in both light and dark treatments. The extent of eyelid encroachment over the eye greater in darkness than in light. Most animals exhibited optomotor responses after experiments, but responses of animals kept in darkness were impaired in comparison to those of animals kept in light.  相似文献   
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Induction of labor by acupuncture electro-stimulation was carried out in 31 patients. This was successful in 21 cases. The pattern of uterine contractions induced in these patients was similar to that in normal labor. No serious fetal or maternal complications occurred. The delay between the commencement of stimulation and the onset of contractions suggests that a humoral mechanism may be involved.  相似文献   
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Nanosecond-pulse fluorimetry of wheat germ agglutinin is analyzed as a function of both excitation and emission wavelengths. When excited at 280 nm, wheat germ agglutinin fluorescence exhibited three lifetimes: one corresponding to the tyrosine residues as a whole and two others corresponding to the tryptophyl emission. The tyrosine contribution to the emission spectrum deduced from this method was in good agreement with that reported previously in steady-state fluorescence experiments [Privat, J.P. and Monsigny, M. (1975) Eur. J. Biochem. 60, 555-567]. The fluorescence decay of each tryptophan residue was not a single exponential function when wheat germ agglutinin was excited at 295 nm. This could be related to the microenvironment of the indole chromophores in the protein. The comparison of the quantum yield and of average lifetime showed that some tryptophan residues were completely quenched. Energy transfer from tyrosines to tryptophan residues previously detected in steady-state fluorescence was also revealed by fluorescence decay measurements. Comparison of both methods showed that an important part of transfers occurred with a very fast rate equal to or greater than 10(10) s-1. Both lifetimes and the ratio of the short and the long-lived component were found dependent on tri-N-acetylchitotriose binding.  相似文献   
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Based on the hitherto published population data of the human red cell PGM1 and acid phosphatase polymorphisms, the geographical distributions of their gene frequencies were analyzed. As far as the acid phosphatase alleles are concerned, a marked geographical gradient was found as the Pa and Pb alleles showed significant correlations with the mean annual temperatures of the various human biotopes (Pa:r = -0.706; Pb:r = +0.812). Against that, the world distribution of the PGM1 alleles did not show a comparable correlation (PGM1 1:R = +0.063; PGM2 1:R = -0.063). The possible reasons for the distribution pattern of the acid phosphatase alleles are discussed.  相似文献   
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From January, 1962, through December, 1973, 1,084 patients with cancer of the intrinsic larynx were treated at the Mayo Clinic. Of the 1,084 patients, 136 were retreated after radiation therapy failed to cure their cancer (105 glottic, 30 supraglottic, and one subglottic cancers). Recurrence of glottic cancer was generally recognized later than recurrences in the supraglottic area; likewise, glottic cancers were more advanced at recurrence than supraglottic growths. When feasible, conservation surgery was carried out on both glottic and supraglottic growths. Unfortunately, many growths were too advanced for conservation surgery by the time recurrence was recognized. The concept of "radiate-and-watch" for early glottic and supraglottic cancers is designed to save larynges. The concept is not supported by this study.  相似文献   
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