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31.
Ivan D. Baronofsky 《The Western journal of medicine》1964,100(3):156-159
The use of colon for esophageal replacement is a procedure that should be considered in the treatment of benign and malignant esophageal lesions. The five-year survival data following operations for carcinoma of the esophagus are not outstanding. The combination of colon transplantation and radiotherapy before and after operation is a procedure that should be utilized if an effort is to be made to increase the survival rate. 相似文献
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34.
W. Arnoldo Levy Ivan Herzog Kunihiko Suzuki Robert Katzman Labe Scheinberg 《The Journal of cell biology》1965,27(1):119-132
No significant change was found in the electrolytes and lipids of the brain analyzed after glutaraldehyde fixation by perfusion of laboratory animals; such fixation also satisfactorily preserves neural tissues for electron microscopy. The brains of normal and tumor-bearing C3H mice, Wistar rats, and New Zealand rabbits were studied. Little difference was found in the dry weight and the content of sodium, potassium, total lipid and lipid fractions, and in the sulfate space (S35O4) between specimens from unperfused and perfused animals, whether normal or tumor-bearing. The results suggest the possibility of using selected regions of the nervous system, dissected after fixation, for chemical study and at the same time characterizing similar regions morphologically with the electron microscope. 相似文献
35.
Advances in technological development have produced an ever-increasing pressure for new and different raw materials to keep pace with changing industrial needs. Many new and useful properties of plants may be discovered through the modern chemistry and technology of utilization research. The U. S. Department of Agriculture’s search for new industrial crops is a coordinated botanical and utilization research program. 相似文献
36.
Ivan Hršel 《Biologia Plantarum》1965,7(6):437-448
The polymorphism of the dictyosomes in the root meristeme ofFagopyrum is connected with their various functions in secretory processes and cell differentiation. The dictyosomes containing vesicular dilatations of the cisternae, which in this object occur more frequently than in others, probably participate in a similar way as the Golgi apparatus of the animal cell in the formation of lysozomes, in the formation of elements belonging to the group of dense bodies analogical lysozomes. These bodies are present in large numbers in the cytoplasm of cells, containing dictyosomes with vesicular dilatations. The other forms of the dictyosomes reveal indications of their participation in the production of the carbohydrate material of the cell walls, like most dictyosomes of other plant objects. However, no fusion of the Golgi vesicles with the plasmalemma was observed. According to their morphological appearance the typical forms of dictyosomes were classified on the basis of their relationship to secretory processes. Simultaneously the morphology and function of the Golgi apparatus was compared in the animal and plant cell. Several morphological varieties of the dictyosomes of plant cells, observed after the action of pathogenic factors and the effect of the fixation procedures, were also noticed in small quantities in the cells of the investigated objects. 相似文献
37.
Summary Human recombinant interleukin-1 (HrIL-1) inhibited WEHI-3B cell growth in a dose-related manner (10–10000 U/ml). Prostaglandin E2 at high concentrations (1000 ng/ml) also inhibited cell growth. When added together, HrIL-1 and prostaglandin E2 inhibited WEHI-3B growth in a synergistic manner (HrIL-1 concentrations of 10–10000 U/ml and prostaglandin E2 concentrations of 10–1000 ng/ml). In contrast to the effects of the cyclooxygenase metabolite of arachidonic acid leukotriene C4, a lipoxygenase metabolite, reversed the cytostatic action of HrIL-1. 相似文献
38.
The aim of this study was to elaborate a method of heterophile mononucleosis antigen preparation useful for latex coating. This antigen was isolated from bovine red blood cells stroma by the technique of Schwarzweiss and Tomcsik with author's own modification, in which introductory extraction of erythrocytes stroma ++ was performed by means of trichloracetic acid, aqueous extraction and elution of active substance with 80% ethanol. Besides of heterophile antigen preparation obtained by the method of Schwerzweiss and Tomcsik (preparation S-T) two serologically++ active preparations were obtained (fraction I and IV), which ability to inhibit PBD agglutinating reaction and bovine red blood cells haemolysis was 16 and 8 times lower, respectively, than S-T preparation. The preparation of heterophile mononucleosis antigen obtained differed in latex coating efficacy. In order to prepare latex reagent MZ-I (from fraction I) a solution of preparation of 125 micrograms/ml concentration was used, for MZ-II (from fraction IV)--50 micrograms and for MZ-III (from preparation S-T)--15 micrograms/ml. The reagent MZ-I showed, the highest activity in agglutinating test with human serum containing heterophile mononucleosis antibodies while two others reacted with 2-4 times lover serum dilutions. Similar differentiated reactivity with these reagents was found in latex test with 15 sera from patients suspected of having infectious mononucleosis. 相似文献
39.
Alterations in Protective Enzymes Against Peroxidation in the Central and Peripheral Nervous System of Control and Dysmyelinating Mutant Mice 总被引:1,自引:1,他引:0
Isabelle Cloëz Ivan Tayarani Frédérique Morel Jean-Marie Bourre 《Journal of neurochemistry》1989,52(5):1353-1358
The activities of peroxide-detoxifying enzymes such as superoxide dismutase (SOD), glutathione peroxidase, glutathione reductase, and catalase were measured in the nervous system of neurological dysmyelinating mutants: quaking (Qk), shiverer (Shi), and trembler (Tr) mice. Cu/Zn-SOD activity was higher in the cerebellum of Qk and Shi mice (by 53% and 106%, respectively) in comparison with controls, but it was the same in the cerebellum of Tr mice and their corresponding controls. In contrast, there was no difference in the level of Cu/Zn-SOD activity in the cerebrum of Qk, Shi, and Tr mice and their respective controls. Mn-SOD activity was the same among all the mutants compared to control animals in both cerebrum and cerebellum. In Shi cerebellum, glutathione peroxidase and glutathione reductase activities were slightly decreased (a 21.6% and a 13.2% diminution, respectively), whereas catalase activity in cerebrum and cerebellum was the same among mutants and control mice. In the sciatic nerve from Tr mice, all the enzymatic activities were enhanced: sixfold increase for total SOD, and 2.4-fold, 3.5-fold, and 1.8-fold increase for glutathione peroxidase, glutathione reductase, and catalase, respectively. 相似文献
40.
Ivan Valiela Joseph Costa Kenneth Foreman John M. Teal Brian Howes David Aubrey 《Biogeochemistry》1990,10(3):177-197
Anthropogenic activities on coastal watersheds increase nutrient concentrations of groundwater. As groundwater travels downslope it transports these nutrients toward the adjoining coastal water. The resulting nutrient loading rates can be significant because nutrient concentrations in coastal groundwaters may be several orders of magnitude greater than those of receiving coastal waters. Groundwater-borne nutrients are most subject to active biogeochemical transformations as they course through the upper 1 m or so of bottom sediments. There conditions favor anaerobic processes such as denitrification, as well as other mechanisms that either sequester or release nutrients. The relative importance of advective vs. regenerative pathways of nutrient supply may result in widely different rates of release of nutrients from sediments. The relative activity of denitrifiers also may alter the ratio of N to P released to overlying waters, and hence affect which nutrient limits growth of producers. The consequences of nutrient (particularly nitrate) loading include somewhat elevated nutrient concentrations in the watercolumn, increased growth of macroalgae and phytoplankton, reduction of seagrass beds, and reductions of the associated fauna. The decline in animals occurs because of habitat changes and because of the increased frequency of anoxic events prompted by the characteristically high respiration rates found in enriched waters. 相似文献