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111.
112.
The Third Annual Carl G. Hartman Lecture. Brain, pituitary gland, and the ovarian cycle 总被引:1,自引:0,他引:1
J W Everett 《Biology of reproduction》1972,6(1):3-12
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The transformation difference spectrum for phytochrome (Pr spectrum minus Pfr spectrum) in pea tissue is determined below 560 nanometers and compared with similar data on phytochrome in vitro The difference spectrum in vivo between phytochrome intermediates and Pfr is also shown for comparison with the data on phytochrome solutions. These comparisons show that the peaks in the spectra occurring in the blue wave lengths are shifted to shorter wave lengths and are much enhanced when phytochrome is extracted from the cell and placed in solution. The results indicate that the physicochemical state of phytochrome in the cell may be different from that of the extracted pigment. 相似文献
116.
A CYTOLOGICAL STUDY OF THE CENTRIFUGED WHOLE, HALF, AND QUARTER EGGS OF THE SEA URCHIN ARBACIA PUNCTULATA 总被引:4,自引:3,他引:1
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Everett Anderson 《The Journal of cell biology》1970,47(3):711-733
While the ooplasmic components of centrifuged eggs of Arbacia punctulata do not stratify in homogeneous layers, we have obtained the following strata beginning with the centripetal end: lipid droplets, pronucleus, clear zone, mitochondria, yolk, and pigment. Whereas mitochondria may be found mingled with yolk bodies, we have never observed lipid droplets nor pigment bodies among any of the other inclusions. The so-called clear zone contains a heterogeneous population of inclusions: annulate lamellae, heavy bodies, Golgi complexes, and rod-containing vacuoles. The peripheral cortical granules of immature (germinal vesicle stage) and of mature eggs are not dislodged from the cortical ooplasm with the centrifugal force utilized. When the eggs are treated with urethane, prior to centrifugation, the cortical granules of mature eggs abandon their peripheral position. Further centrifugation of the initially stratified eggs produces nucleated and nonnucleated halves and the centrifugation of the halves results in quarters. The cytology of the halves and quarters is discussed. The halves and quarters have been activated with either sperm or hypertonic sea water. With the exception of the nucleated halves, we were unable to obtain plutei larvae from the other fractions (red halves and quarters). We believe that the lack of development of the various fragments is a function of the balance of particular inclusions necessary for differentiation. 相似文献
117.
THE APPEARANCE AND STRUCTURE OF INTERCELLULAR CONNECTIONS DURING THE ONTOGENY OF THE RABBIT OVARIAN FOLLICLE WITH PARTICULAR REFERENCE TO GAP JUNCTIONS 总被引:16,自引:11,他引:5
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Lanthanum tracer and freeze-fracture electron microscope techniques were used to study junctional complexes between granulosa cells during the differentiation of the rabbit ovarian follicle. For convenience we refer to cells encompassing the oocyte, before antrum and gap junction formation, as follicle cells. After the appearance of an antrum and gap junctions we call the cells granulosa cells. Maculae adherentes are found at the interfaces of oocyte-follicle-granulosa cells throughout folliculogenesis. Gap junctions are first detected in follicles when the antrum appears. In early antral follicles typical large gap junctions are randomly distributed between granulosa cells. In freeze-fracture replicas, they are characterized by polygonally packed 90-Å particles arranged in rows separated by nonparticulate A-face membrane. A particle-sparse zone surrounds gap junctions and is frequently occupied by small particle aggregates of closely packed intramembranous particles. The gap junctions of granulosa cells appear to increase in size with further differentiation of the follicle. The granulosa cells of large Graafian follicles are adjoined by small and large gap junctions; annular gap junctions are also present. The large gap junctions are rarely surrounded by a particle-free zone on their A-faces, but are further distinguished by particle rows displaying a higher degree of organization. 相似文献
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Seven cases of struma lymphomatosa are presented. Two patients had known enlargement of the thyroid for five or more years. In five cases only unilateral involvement was discernible at the time of operation. In one case there was a small nodule in the least involved side. In another there was diffuse involvement. Two of the patients were males. There has been recurrence in three of six cases in which partial thyroidectomy was performed. Only one patient with recurrence was treated with x-ray, apparently with satisfactory results. Six of the seven patients had a postoperative basal metabolic rate below normal. Three of them required desiccated thyroid for symptomatic relief. 相似文献
120.
Harold J. Chapman Everett H. Dickinson Emanuel Rollins Gerald L. Crenshaw R. Maurice Hood 《The Western journal of medicine》1953,78(6):496-498
Major wounds of the chest usually cause immediate or early death. Of 35 patients with major thoracic battle injuries who were treated in one naval hospital, six had non-penetrating wounds of the chest and other areas. Of the 29 with penetrating wounds of the chest, 23 were treated by aspiration of hemothorax, decortication in three cases, and thoracotomy for control of hemorrhage in one case and for removal of a foreign body in another.Four cases are reported, two to illustrate the usual course of treatment and two in which the patient died. 相似文献