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421.
Max H. Cohen Ronald J. Elin Barry J. Cohen 《Cancer immunology, immunotherapy : CII》1991,32(5):315-324
Summary Four patients developed serious hypotension and signs of disseminated intravascular coagulation shortly after a second round of Tice bacillus Calmette-Guérin (BCG) injections into locally recurrent cutaneous melanoma satellite nodules. Each of these patients survived following intensive therapy with isoniazid, pyridoxine, steroids, pressors, antibiotics, and cardio-renal support including, in one case, three acute hemodialyses. Plasma specimens from two of the four patients caused gelation of lysate from the amebocytes ofLimulus polyphemus, indicating the presence of endotoxin or an endotoxin-like substance. In vitro studies on the BCG preparations led us to conclude that this endotoxin activity in the plasma is not the result of direct injection of endotoxin with the BCG preparation, but rather from release of endotoxin from endogenous sources, such as the intestinal tract during a period of relative hypotension following an allergic reaction. Prior immunity appeared to be the consistent factor in the toxic reactions reported herein. Finally, we present recommendations for serial monitoring of these patients and discuss the use of an alternative agent for intralesional therapy. 相似文献
422.
We tested whether differences in ploidy level and previous exposure to herbivory can affect plant tolerance to herbivory.
We conducted a common garden experiment with 12 populations of two ploidy levels of the perennial herb Cardamine
pratensis (five populations of tetraploid ssp. pratensis and seven populations of octoploid ssp. paludosa). Earlier studies have shown that attack rates by the main herbivore, the orange tip butterfly Anthocharis cardamines, are lower in populations of octoploids than in populations of tetraploids, and vary among populations. In the common garden
experiment, a combination of natural and artificial damage significantly reduced seed and flower production. We measured tolerance
based on four plant-performance metrics: survival, growth, seed production and clonal reproduction. For three of these measurements,
tolerance of damage did not differ between ploidy levels. For clonal reproduction, the octoploids had a higher tolerance than
the tetraploids, although they experience lower herbivore attack rates in natural populations. Populations from sites with
high levels of herbivory had higher tolerance, measured by seed production, than populations with low levels of herbivory.
We did not detect any significant costs of tolerance. We conclude that high intensity of herbivory has selected for high tolerance
measured by seed production in C. pratensis. 相似文献