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991.
992.
Robert L. Gray Frederick J. Wenzel Dean A. Emanuel 《Applied and environmental microbiology》1969,17(3):454-456
Farmer''s lung is a serious disabling pulmonary disease found in agricultural workers. The disease is believed to be a hypersensitivity to the thermophilic actinomycetes, principally Thermopolyspora polyspora. This organism is difficult to stain with the usual bacteriological stains and thus far has not been demonstrated in the lung tissue by microscopic methods. In this paper, it is demonstrated that the fluorescent-antibody technique is a simple method for the positive identification of T. polyspora. The technique can also be used as a rapid screening test for the detection of antibodies to T. polyspora in the patient''s serum. In addition, it opens up the possibility of the identification of T. polyspora in the lung tissue of patients with farmer''s lung and makes available a means for the study of the immunological reaction in the lung parenchyma. No false positive or cross-reactions with Thermoactinomyces vulgaris or Streptomyces griseus could be demonstrated. 相似文献
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Frederick Archibald 《Biotechnology and bioengineering》1979,21(9):1553-1559
A number of devices for the control of the dissolved oxygen (DO) tension in small continuous cultures are now in use, but because of the sophisticated proportional control employed, are prohibitively expensive for many applications. This report describes a flexible cost-efficient DO monitor and controller which, including DO probe, valves, and gas solenoid, can be constructed for 400 dollars. The device employs two-position control of gas flow and agitation speed and is readily adaptable to a variety of application; Construction, operation, and performance in conjunction with a small fermentor are briefly discussed. 相似文献
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The high potency with which acetylcholine (ACh) inhibits the binding of the specific muscarinic agonist, [3H] methyldioxolane ([3H]CD), has provided the basis for the development of a radio-receptor assay for estimation of ACh. A synaptosomal preparation of the rat cerebral cortex was used as a source of muscarinic receptors. When binding assays were run at 0°C, the IC50 value of ACh was approximately 5 × 10?9 M, which corresponds to 2.5 – 10 pmoles of ACh, depending upon the assay volume. The ACh content of the rat cerebral cortex and corpus striatum was measured following fast microwave irradiation. By measuring the displacement of [3H]CD binding caused by aliquots of the supernatant from tissue homogenates and comparing the displacement values with an ACh standard curve, the ACh content of the cerebral cortex and corpus striatum was calculated to be 19 and 55 nmoles/g wet tissue weight, respectively. 相似文献