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971.
Highly sensitive and specific erythrocyte diagnostic agents (ED) for the determination of antibodies to Proteus O-antigens have been obtained by the sensitization of formolated sheep red blood cells (SPBC) with activated lipopolysaccharides (LPS) without the use of mediators. The tannin treatment of formolated SRBC and/or the increase of temperature from 45 degrees C to 100 degrees C in the process of the preparation of ED have been found to produce no increase in effectiveness. Antibody ED permitting the detection of Proteus O- and H-antigens has been obtained by the sensitization of formolated chick red blood cells with immunoglobulin preparations to Proteus hydroxylamine antigens, carried out with the use of amidol. The experiments have shown the possibility of using this antibody ED for the determination of O-antibodies in the antigen neutralization test with nonactivated LPS used as an agglutinating agent. The passive hemagglutination test with antibody ED has proved to be a more sensitive method for the detection of O-antibodies than the antigen neutralization test with antigenic ED. The determination of Proteus etiology in the passive hemagglutination test with the use of antigenic ED has been shown to be highly effective in the examination of patients with chronic osteomyelitis at the stage of exacerbation.  相似文献   
972.
973.
In the present day practice of surgical anesthesia, drugs and techniques are used which require or lead to cessation of voluntary respiration by the patient. Respiration is then controlled by the anesthesiologist. At the termination of operation many patients do not breathe adequately for variable periods of time. The causes include obstruction, excessive sedation, muscle relaxants, the effect of controlled respiration itself and various miscellaneous factors. A diagnosis is made by taking into consideration the drugs and techniques which have been used and the character of the patient''s respiratory efforts, if any. The cause may then be treated. In some cases antidotes are available. However, until truly adequate spontaneous respiration is observed for some time the patient must have his efforts assisted. High oxygen concentrations must not be substituted for adequate ventilation.  相似文献   
974.
975.
976.
Hierarchical down-modulation of hemopoietic growth factor receptors   总被引:31,自引:0,他引:31  
F Walker  N A Nicola  D Metcalf  A W Burgess 《Cell》1985,43(1):269-276
Granulocytes and macrophages can be produced in vitro when progenitor cells from mouse bone marrow are stimulated by any of four distinct colony stimulating factors, Multi-CSF (IL-3), GM-CSF, G-CSF, and M-CSF (CSF-1). At 0 degrees C the four CSFs do not cross-compete for binding to bone marrow cells, indicating that each has a specific cell surface receptor. However, at 21 degrees C or 37 degrees C, Multi-CSF inhibits binding of the other three CSFs and GM-CSF inhibits binding of G-CSF and M-CSF. Rather than competing directly for receptor binding, the binding of Multi-CSF, GM-CSF, or G-CSF to their own receptor induces the down-modulation (and thus activation) of other CSF receptors at 37 degrees C. The pattern and potency of down-modulation activity exhibited by each type of CSF parallels the pattern and potency of its biological activity. We propose a model in which the biological interactions of the four CSFs are explained by their ability to down-modulate and activate lineage-specific receptors.  相似文献   
977.
978.
The possibility of detecting Pseudomonas aeruginosa and other Gram-negative bacteria in the air of the burn department at the Institute of Surgery was studied. The investigation of large volumes of air (0.5-1 m3) in the wards and the corridor with the use of a new bacteriological aerosol sampler, model IIAB-5, resulted in the detection of Pseudomonas aeruginosa. Besides, in a number of other rooms Klebsiella, Proteus, Citrobacter and Enterobacter were detected in the air. The possibility of the spread of Gram-negative opportunistic bacteria through the air in hospital conditions is discussed.  相似文献   
979.
980.
1. Testosterone reduces the haemolytic action of Ekatin on the morphotic blood elements by accelerating maturation of erythroblastic cells. 2. Testosterone, by accelerating the metabolism of the pesticide causes a defective defence processes of the organism by decreasing the number of macrophages. 3. Intoxication of androgenised birds with Ekatin leads to a breakdown of the systemic adaptive mechanisms by rapid and early switching on the adrenal cortex in response to the stress caused by poisoning.  相似文献   
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