Abstract: The invention provides a method for selecting hybridomas which produce antibodies specific to domains of a cell surface antigen which is usually not accessible at the surface of intact cells. The method employs the screening of the hybridoma clones obtained for the production of antibodies specific against the cell surface antigen by use of immunoblotting analysis, namely by screening the clones against antigen immobilized on a solid substrate such as nitrocellulose. The invention also includes those hybridomas and monoclonal antibodies when produced according to the method. The method provides monoclonal antibodies to P-glycoprotein surface antigen correlated with multidrug resistance. The antibodies are used to obtain a cDNA probe which in turn was used to select a cDNA clone encoding for a portion of the P-glycoprotein including the C-terminal end.

Abstract: In radiotherapy use is made of apparatus of the type in which a chain of balls comprising radioactive balls and inert spacer balls is moved pneumatically to and from an applicator tube within the patient, the spacer balls are made of a material such as nylon which is softer and less dense than the radioactive balls, and is radiographically transparent. This reduces wear and tear on the radioactive balls and facilitates control of dosage and monitoring of the treatment. The balls are sorted after use by means of a radiation detector. The ball chain has a large diameter end ball of ferromagnetic material, which blocks air flow through the applicator when correctly located therein, and whose position can be verified by an induction coil.

Abstract: The invention provides a nucleic acid having a sequence which encodes a polypeptide that is at least part of a T cell antigen receptor. This encoded sequence is about 936 nucleotides in length and preferably is a human T cell antigen receptor. The nucleic acid sequence of one embodiment of the invention is shown in FIG. 3.The nucleic acid sequence may be used as a probe to determine whether an unknown cell, e.g., a tumor cell, is a T cell.Polypeptides encoded by the nucleic acid sequence include about 312 amino acids and are at least part of a T cell antigen receptor. They include at least one sequence which over 21 contiguous amino acids has greater than about 35% homology with mouse and human immunoglobin .lambda. light chains.Antibody to the polypeptide may be prepared and used to identify T cell antigen receptor and to determine whether an unknown cell, e.g., a tumor cell, is a T cell.

Abstract: Anthropomorphic phantoms for radiological testing, assessment and training are prepared by obtaining a radiograph of a body part to be simulated, translating the radiograph into densitometric data, translating the densitometric data into thickness data representing the thickness of a selected phantom material required to produce that density under conditions similar to those used to produce the original radiograph, and using the thickness data obtained to produce, for example by employing a numerically controlled milling machine, a three dimensional representation of those thicknesses on the selected material which matches the radiographic image forming characteristics of the original body part when imaged under similar conditions.

Abstract: An ultrasonic imaging device includes a transducer assembly for transmitting ultrasound pulses into a portion of a structure to be imaged and receiving ultrasound scattered by said structure portion and generating signals in response thereto, means to energize said transducer assembly to transmit said pulses, scanning means for progressively relating said transducer assembly to successive portions of said structure according to a scanning pattern, and receiver and signal processing means for assembling an image from said generated signals, the transducer assembly comprising separate transmitting and receiving transducers, one of said transducers being a simulated conical transducer having a line focus, and the other of said transducers having its axis in parallel alignment with said line focus, the scanning means being operative to move said line focus in relation to a structure to be imaged in accordance with said scanning pattern.

Abstract: Method for producing pancreatic islet-like structures (ILS's) having histology and insulin-producing properties corresponding to those of fetal pancreatic islets and islets from adult animals maintained in culture. The ILS's are produced by culturing isolated natural pancreatic islets, pancreatic duct pieces, cell clusters consisting of mildly digested pieces of pancreas, cell tissues obtained as by-products of the culturing methods, or previously-produced ILS's, in attachment to a substrate.

Abstract: An ultrasonic image of improved resolution is obtained by utilizing separate transducers for transmission and reception of ultrasonic pulses utilized for imaging, one transducer being a cylindrical or simulated cylindrical transducer having a line focus and the other transducer being aimed along the focus of the first transducer. An area to be imaged may be scanned by rotating and/or traversing the transducers as a unit.

Abstract: An ultrasonic image of improved resolution is obtained by utilizing separate transducers respectively for transmission and reception of ultrasonic pulses employed for imaging a subject, one transducer being a conical or simulated conical transducer having a line focus along the cone axis and the other transducer being aimed along the line focus of the first transducer. An area to be imaged may be scanned by moving the transducers as a unit about the subject portion to be examined.