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11.
Weaning success of pond‐cultured pikeperch and wild‐caught perch (mean length 51 and 48 mm respectively) was evaluated using different weaning techniques and different formulated feeds. Juveniles that were fed formulated feed grew as well as or better than juveniles that were weaned successively using zooplankton or yolk. Four different formulated feeds (agglomerated marine larvae feed, marine larvae feed, trout feed and a semi‐moist feed) were evaluated regarding specific growth rate (SGR), condition factor and a subjective stomach fullness estimate. The agglomerated marine larvae feed gave significantly better weaning performance than the other feeds regarding all parameters (SGR = 7.3% day?1 and 3.4% day?1 for pikeperch and perch respectively).  相似文献   
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Heart and skeletal muscle inflammation (HSMI) is a disease syndrome of unknown aetiology first observed in farmed Atlantic salmon, Salmo salar, in 1999. In the present study we have demonstrated for the first time that HSMI is an infectious disease. It was induced in Atlantic salmon post-smolts after injection with tissue homogenate from farmed Atlantic salmon previously diagnosed with HSMI. The lesions were also induced in cohabitating salmon given a corresponding injection without tissue homogenate. Six weeks post-challenge the fish that had been injected with tissue homogenate developed a serious epicarditis and myocarditis with mononuclear cell infiltrations in compact and spongy layers of the heart. Similar lesions were found in cohabitants after 10 weeks. The lesions were consistent with samples from field outbreaks of HSMI. No lesions were found in control fish. A viral aetiology is strongly suggested, as no difference in disease induction between an inoculum containing antibiotics and a non-treated inoculum was found. Further investigations are required in order to make conclusions regarding the cause and pathogenesis of HSMI.  相似文献   
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Monoclonal antibody-mediated tumor regression by induction of apoptosis   总被引:166,自引:0,他引:166  
To characterize cell surface molecules involved in control of growth of malignant lymphocytes, monoclonal antibodies were raised against the human B lymphoblast cell line SKW6.4. One monoclonal antibody, anti-APO-1, reacted with a 52-kilodalton antigen (APO-1) on a set of activated human lymphocytes, on malignant human lymphocyte lines, and on some patient-derived leukemic cells. Nanogram quantities of anti-APO-1 completely blocked proliferation of cells bearing APO-1 in vitro in a manner characteristic of a process called programmed cell death or apoptosis. Cell death was preceded by changes in cell morphology and fragmentation of DNA. This process was distinct from antibody- and complement-dependent cell lysis and was mediated by the antibody alone. A single intravenous injection of anti-APO-1 into nu/nu mice carrying a xenotransplant of a human B cell tumor induced regression of this tumor within a few days. Histological thin sections of the regressing tumor showed that anti-APO-1 was able to induce apoptosis in vivo. Thus, induction of apoptosis as a consequence of a signal mediated through cell surface molecules like APO-1 may be a useful therapeutic approach in treatment of malignancy.  相似文献   
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Mauna Loa volcano, Hawaii, deforms by a combination of shallow dike intrusions in the rift zones and earthquakes along the base of the volcano, but it is not known how the spreading is accommodated in the lower part of the volcanic edifice. We present evidence from interferometric synthetic aperture radar data for secular inflation of a dike-like magma body at intermediate depth in the southwest rift zone during 2002 to 2005. Magma accumulation occurred in a section of the rift zone that was unclamped by previous dikes and earthquakes, suggesting that stress transfer plays an important role in controlling subsurface magma accumulation.  相似文献   
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Falk D 《Science (New York, N.Y.)》1983,221(4615):1072-1074
An endocast of the frontal lobe of a reconstructed skull, which is approximately 2 million years old, from the Koobi Fora region of Kenya appears to represent the oldest human-like cortical sulcal pattern in the fossil record, while the endocast from another skull from the same region produces an endocast that appears apelike in its frontal lobe and similar to endocasts from earlier South African australopithecines. New analysis of paleoanatomical evidence thus indicates that at least two taxa of early hominids coexisted in East Africa.  相似文献   
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The cytokine interleukin-10 (IL-10) has shown promise in clinical trials for treatment of inflammatory bowel disease (IBD). Using two mouse models, we show that the therapeutic dose of IL-10 can be reduced by localized delivery of a bacterium genetically engineered to secrete the cytokine. Intragastric administration of IL-10-secreting Lactococcus lactis caused a 50% reduction in colitis in mice treated with dextran sulfate sodium and prevented the onset of colitis in IL-10(-/-) mice. This approach may lead to better methods for cost-effective and long-term management of IBD in humans.  相似文献   
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