Abstract: Mixed anhydrides products are described. These mixed anhydrides are produced by reaction of a carboxylic acid-containing steroid with a material having the formula: ##STR1## wherein: X is a halogenZ is an oxygen or sulfurR is a hydrocarbonin an inert organic solvent containing a Lewis base. These mixed anhydrides may in turn be reacted with, for example, an alcohol ammonia or amine to produce the corresponding ester or amide steroid.

Abstract: A method for detecting the presence of Mycobacteria in a fluid or tissue which comprises mixing the fluid or tissue containing a secretory product of Mycobacteria with a complex of a tracer-containing molecule and a binding macromolecule having reversible binding affinity for the tracer-containing molecule and detecting the tracer-containing molecule, wherein the tracer-containing molecule is a charcoal-adsorbable protein from Mycobacterium tuberculosis which has a molecular weight of 20,000-30,000 and which is immunochemically stable from 4.degree. C. to 250.degree. C. and has a pH range from 3.0 to 9.0. The method is particularly applicable to the detection of infectious tuberculosis in humans and determining the antibiotic sensitivity of infecting Mycobacteria.

Abstract: A process for the detection of antibodies in a test sample is described. This process involves:(a) preparing an essentially isotonic and low ionic strength suspension comprising said sample and erythrocytes in net negatively-charged form;(b) maintaining said suspension for at least 30 seconds;(c) combining said suspension with an amount of a solution of polymer effective for agglutination of said erythrocytes;(d) separating the resultant agglutinates of polymer and erythrocytes from supernatant of said suspension;(e) dispersing said agglutinates in a hypertonic salt solution having an essentially neutral pH; and(f) monitoring the dispersed agglutinates for dissociation of erythrocytes.This process permits rapid detection of antibodies with great ease. Their presence is indicated by persistence of the agglutinates in the dispersion. The antigen which reacts with antibody may be native to the erythrocytes, or may be unrelated to erythrocytes but artificially coupled to those cells.

Abstract: A method and apparatus for detecting respiratory distress is disclosed wherein the increasing force of contraction of the heart, which occurs during a respiratory distress condition is detected and utilized to signal the condition. More particularly, the increasing force of contraction of a patient's heart, which affects the electrical signal generated by an impedance pneumograph may be detected by utilizing the heart beat of the patient to generate a trigger pulse. The trigger pulse is used as a timing means to enable the effects of the heart as registered on the impedance pneumograph, to be detected and compared, with an increase in amplitude of the contractions of the heart indicating a respiratory failure.