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1.
LJ Lanzerotti K Rinnert G Dehmel FO Gliem EP Krider MA Uman J Bach 《Science (New York, N.Y.)》1996,272(5263):858-860
During the Galileo probe's descent through Jupiter's atmosphere, under the ionosphere, the lightning and radio emission detector measured radio frequency signals at levels significantly above the probe's electromagnetic noise. The signal strengths at 3 and 15 kilohertz were relatively large at the beginning of the descent, decreased with depth to a pressure level of about 5 bars, and then increased slowly until the end of the mission. The 15-kilohertz signals show arrival direction anisotropies. Measurements of radio frequency wave forms show that the probe passed through an atmospheric region that did not support lightning within at least 100 kilometers and more likely a few thousand kilometers of the descent trajectory. The apparent opacity of the jovian atmosphere increases sharply at pressures greater than about 4 bars. 相似文献
2.
The cell-mediated immune response of blood lymphocytes from 110 untreated dogs with different tumours was evaluated. The influence of different tumour types on the cellular immune system was examined by assessing the percentage of isolated large granular lymphocytes (LGL), in vitro natural cytotoxicity and mitogen-induced lymphocyte proliferation. Although the overall natural cytotoxicity of dogs with different tumours was decreased, the overall difference from control values was not statistically significant. However, mitogen-induced lymphocyte proliferation was significantly depressed in dogs with tumours in comparison with the controls. Dogs with mammary carcinomas showed significantly lower natural cytotoxicity than controls and dogs with myeloid neoplasms showed significantly lower mitogen-induced lymphocyte proliferation. Abnormalities exist not only in natural cytotoxicity but also in mitogen-induced lymphocyte proliferation. For the dog, this is the first study to assess the influence of different tumours using a combined evaluation of natural cytotoxicity and mitogen-induced lymphocyte proliferation in such a large number of animals. 相似文献
3.
4.
Henry Jrgensen Anja Serena Mette S. Hedemann Knud Erik Bach Knudsen 《Livestock Science》2007,109(1-3):111-114
Adult sows have a more developed gastro-intestinal system than young growing pigs resulting in a superior capacity to digest fibrous components. The main objective of this study was to describe the capacity of sows and growing pigs to digest the fibre components in concentrated low dietary fibre (DF) diet and two high DF diets similar in DF but with contrasting DF solubility. Six sows and four growing pigs were fitted with a simple T-cannula at the terminal ileum. Each balance experiment consisted of a 7-day initial period followed by a 3-day collection of faeces and a 2 or 3-day collection of ileal digesta for growing pigs and adult sows, respectively. When feeding diets with high proportions of soluble non-starch polysaccharides (NSP), the difference in fermentation capacity between growing pigs and adult sows was small. The adult sows showed a higher fermentative capacity, evidenced by a higher fermentation and a higher methane production, when high fibre diet with high amount of insoluble fibre was fed. 相似文献
5.
Kenaf (Hibiscus cannabinus) plants are widely known for their contribution to the global and regional environment because of their ability to fix CO2. On the other hand, some scientists have doubts about CO2 fixation by kenaf and have misgivings about the effect of kenaf on the ecosystem. We have characterized the structural characteristics
of cell walls of bast fibers, cores, roots, and leaves of kenaf during the maturation of plants and investigated the rate
of photosynthesis. During maturation of the kenaf plant the cellulose (bast fiber 52–59%, core 44–46%) and lignin (bast fiber
9.3–13.2%, core 18.3–23.2%) contents increased significantly. The aromatic composition of the lignin of bast fiber was significantly
different from that of the core lignin and of other plants. The lignin of bast fiber appears similar to pure syringyl lignin.
Fixation of CO2 by kenaf plants and their contribution to the global environment are discussed. A significatly high rate of photosynthesis
of kenaf plants was observed compared to that of woody plants in Japan, but the amount of CO2 fixation depends on the characteristics of the plantation. If the kenaf was planted in high density, about twice as much
CO2 was fixed as was fixed by trees in a tropical rain forest.
Received: April 22, 2002 / Accepted: July 24, 2002
Acknowledgments This project was supported by the Science and Technology Agency (STA) fellowship of the Japan International Science and Technology
Exchange Center (JISTEC), which has been successfully applied by Dr. Shuji Hosoya, Forestry and Forest Products Research Institute.
We thank Dr. Toshio Sumizono and Mr. Masao Sakurai, Forestry and Forest Products Research Institute, for their kind help in
determining the rate of photosynthesis and cultivating the kenaf plants, respectively. We also express our appreciation to
Dr. Quang Hung Le, College of Agriculture and Forestry, Ho Chi Minh City, Vietnam for offering information about the cultivation
of kenaf at Thu Duc District, Ho Chi Minh City. 相似文献
6.
7.
Transplantation: pairing of donor and recipient 总被引:5,自引:0,他引:5
F H Bach 《Science (New York, N.Y.)》1970,168(936):1170-1179
8.
Cell mediated immunity: separation of cells involved in recognitive and destructive phases 总被引:43,自引:0,他引:43
F H Bach M Segall K S Zier P M Sondel B J Alter M L Bach 《Science (New York, N.Y.)》1973,180(84):403-406
The mixed leukocyte culture (MLC) and the cell mediated lympholysis (CML) assays are used as in vitro models of the afferent, or recognitive, and efferent, or destructive, phases of the homograft reaction. Activity in both of these tests has been related to differences at the major histocompatibility complex, HL-A in man and H-2 in mouse. Recent evidence suggests that the presumed cell surface differences which lead to cell proliferation in MLC are different from those which act as a target for CML. Data are presented providing further support for this hypothesis; in addition separate cell populations may respond to the differences which activate cells in MLC and to the differences which serve as targets for CML. There thus appears to be a dichotomy both for genetic control of, and cell populations involved in, the recognitive and destructive phases of cell mediated immunity. 相似文献
9.
Genetic and immunological complexity of major histocompatibility regions 总被引:24,自引:0,他引:24
There are genetic differences within the major histocompatibility complex of the mouse which lead to skin graft rejection but which cannot be detected serologically. When confronted with these differences on allogeneic cells, lymphocytes proliferate in vitro. In other cases, in vitro lymphocyte proliferation but no skin graft rejection is associated with loci that are linked to but genetically separable from the loci controlling the serologically defined antigens. 相似文献
10.
One-way stimulation in mixed leukocyte cultures 总被引:67,自引:0,他引:67
We have developed an improved method for the mixed leukocyte culture test. Control values, as determined by rates of incorporation of thymidine, are very low, allowing evaluation of low levels of stimulation in homologous cell mixtures. One-way stimulation is assayed by treating the cells of one individual with mitomycin C; treated cells cannot respond (incorporate thymidine) but can still stimulate homologous untreated cells to do so. 相似文献