摘要:
An osteoimplant is provided which comprises a coherent aggregate of elongate bone particles, the osteoimplant possessing predetermined dimensions and shape. The osteoimplant is highly absorbent and sponge-like in nature. Also provided herein are a method of fabricating the osteoimplant and a method of repairing and/or treating bone defects utilizing the osteoimplant.
摘要:
An osteoimplant is provided which comprises a coherent aggregate of elongate bone particles, the osteoimplant possessing predetermined dimensions and shape. The osteoimplant is highly absorbent and sponge-like in nature. Also provided herein are a method of fabricating the osteoimplant and a method of repairing and/or treating bone defects utilizing the osteoimplant.
摘要:
A method of manufacturing an osteoinductive osteoimplant is provided which comprises the steps of: demineralizing part or all of at least one surface of a monolithic section of cortical bone to a depth of at least about 100 microns; and, configuring the monolithic section of cortical bone to provide an osteoimplant possessing an outer surface possessing at least one demineralized zone and a non-demineralized zone. An implant produced according to the above method demonstrates improved osteoinduction without producing any clinically significant reduction of strength in critical regions of the osteoimplant.
摘要:
A method of manufacturing an osteoinductive osteoimplant is provided which comprises the steps of: demineralizing part or all of at least one surface of a monolithic section of cortical bone to a depth of at least about 100 microns; and, configuring the monolithic section of cortical bone to provide an osteoimplant possessing an outer surface possessing at least one demineralized zone and a non-demineralized zone. An implant produced according to the above method demonstrates improved osteoinduction without producing any clinically significant reduction of strength in critical regions of the osteoimplant.
摘要:
A bone-derived implant is provided which is made up of one or more layers of fully mineralized or partially demineralized cortical bone and, optionally, one or more layers of some other material. The layers constituting the implant are assembled into a unitary structure to provide an implant exhibiting good overall load-supporting properties.
摘要:
A pressure flow system and method for its use are provided for contacting the interior of a fluid permeable, e.g., porous, workpiece. The system includes a fluid pressure chamber having an inlet port and an opening formed in one of the chamber walls. An adjustable seal capable of providing a fluid-tight seal about the exterior of a workpiece having a non-uniform surface is positioned within the opening. Fluid under pressure is supplied to the pressure chamber to force fluid to flow through the internal matrix of the workpiece. In a preferred embodiment, the workpiece is a bone or a section thereof, and the fluid is forced to flow from the endosteal portion of bone to the periosteal portion of bone through the vasculature and porous structure of the bone to remove blood, bone marrow and/or other non-bone constituent(s) from the bone. Alternatively, the fluid can be chosen to decontaminate and/or demineralize the bone, to stain the bone to improve visualization of the bone microvasculature or to impregnate with pharmacological agents (antibiotics, bone growth factors, etc.) so that bone can act as a delivery system.
摘要:
A multipart intervertebral implant is provided which includes an implant portion and an implant extender portion. The implant portion and the implant extender portion can be fastened together using any known fastening means including pins, interlocking structure (e.g., dovetail, tongue and groove, etc.), adhesives, etc. The size of the implant extender portion can be selected during a surgical procedure to provide an implant suitable for a particular intervertebral receiving bed. An intervertebral implant is also provided which may be formed from a multiplicity of implant sections which are fastened together to provide an implant having a desired length. Implants having surface configurations which more closely correspond to the configuration of vertebral endplates are also provided.
摘要:
A digital data communications system employing correlation detection is disclosed as comprising an encoding system which encodes successive k-bit data words from a data source into predetermined start-stop phases of either a 2.sup.k -bit repeating pseudorandom binary code or a 2.sup.k -1 bit repeating pseudorandom binary code and a decoding system which receives the stream of ones and zeros in the pseudorandom binary code from the encoder and reproduces therefrom, using a correlation detector and associated circuitry, a replica of the original k-bit data word from the data source. Undesirable signal variations in the output of the correlation detector caused by a frequency translation error introduced in the transmission and reception of the pseudorandom binary code is eliminated by a feedback system which detects the effects of the frequency translation error at the output of the correlation detector and applies a frequency correction signal component to the pseudorandom binary code which offsets the frequency translation error prior to introduction of the pseudorandom binary code to the correlation detector.
摘要:
A digital data communications system employing correlation detection is disclosed as comprising an encoding system which encodes successive k-bit data words from a data source into predetermined start-stop phases of either a 2.sup.k -bit repeating pseudorandom binary code or a 2.sup.k -l bit repeating pseudorandom binary code and a decoding system which receives the stream of ones and zeros in the pseudorandom binary code from the encoder and reproduces therefrom, using a correlation detector and associated circuitry, a replica of the original k-bit data word from the data source. Undesirable signal variations in the output of the correlation detector caused by a frequency translation error introduced in the transmission and reception of the pseudorandom binary code is eliminated by a feedback system which detects the effects of the frequency translation error at the output of the correlation detector and applies a frequency correction signal component to the pseudorandom binary code which offsets the frequency translation error prior to introduction of the pseudorandom binary code to the correlation detector. In lieu of the feedback system, a frequency translation error can also be minimized through the use of minimum shift keying (MSK) encoding and decoding apparatus respectively provided in the encoding and decoding systems, upstream of the correlation detector.
摘要:
A distance measuring system is provided including a ground station transponder continuously transmitting a repeating pseudorandom coded bit pattern, and at least one aircraft interrogator receiving and locking onto the ground station signal. The aircraft interrogator transmits a coded interrogation signal in precise synchronism with an arbitrarily selected any one of the repetitive code words (bit patterns) that comprise the repeating pseudorandom coded bit pattern which are coded identically with the interrogation signal and waits for a reply. If the ground station receives the coded interrogation signal in synchronism with an identically coded word in its continuous transmission, it transmits a reply signal to the aircraft interrogator optionally encoded with synchronism error or interrogation steering information. If no reply is received by the aircraft interrogator, it transmits its next coded interrogation signal shifted by one or more bits relative to the arbitrarily selected received code word from the ground station. Successive interrogation signals are each shifted an additional predetermined number of bits until synchronism is attained and a reply signal is received. The number of bits of shifting performed by the aircraft needed for synchronization when combined with the number of bits representing the whole code word intervals elapsing between transmission of an interrogation and receipt of a reply represents the distance between the ground station and aircraft. The optionally encoded synchronism error and steering information is respectively utilized by the aircraft to more precisely calculate distance and alter its time of interrogation.