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Immunologic and pharmacologic concepts of monoclonal antibodies   总被引:2,自引:0,他引:2  
While monoclonal antibodies have solved many of the difficulties of using immunologic reagents for radioimmunodiagnosis and therapy, in the 13 years since their introduction a number of persistent problems remain, most notably a low yield of antibody-producing cells from the fusion process, difficulty in obtaining high-affinity antibodies, and the potential immunogenicity of murine immunoglobulins (Igs). Several solutions are under development, including fusion techniques that enrich for cells producing desired antibodies, production of human-mouse chimeric antibodies by recombinant DNA technology, and the generation of human monoclonal antibodies by promising new approaches. Until these upcoming methodologies are established, and to better direct their development and application, a sound understanding of the pharmacology of presently available native and modified monoclonal antibodies is crucial. Although much has been already determined in this area, a great deal of further clarification remains necessary.  相似文献   
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Facial muscle spasms, which are rare in adults, present a particularly difficult entity for the optometrist to recognise. The condition may not even manifest itself at an eye examination and the optometrist may have to rely on subjective symptoms to assist in the recognition of the condition. It is important to diagnose the condition correctly as specific and effective treatment is available.  相似文献   
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The objectives of this study were to evaluate and compare the shear bond strengths and bond failure locations of 2 currently available orthodontic ceramic brackets. Forty polycrystalline ceramic brackets (Clarity, 3M Unitek, Monrovia, Calif) and 40 monocrystalline ceramic brackets (Inspire, Ormco, Orange, Calif) were bonded to 80 extracted premolars with the same bonding system. All bonded specimens were placed in distilled water for 42 hours at 37 degrees C followed by thermal cycling for 700 complete cycles. Forty ceramic brackets, 20 of each type, were tested on a universal testing machine to determine the shear force levels required to debond them. Forty ceramic brackets were removed with the debonding pliers recommended by the manufacturers. All teeth were examined under an optical microscope, and the adhesive remnant index was used to assess the bond failure locations. The mean shear bond strength of the Clarity brackets was 21.67 +/- 5.19 MPa, and the mean shear bond strength of the Inspire brackets was 20.32 +/- 8 MPa. The mean shear bond strengths of both brackets were higher than those considered clinically optimal. Most of the brackets (85% of Clarity and 75% of Inspire) tested on the machine failed at the bracket-adhesive interface. One premolar bonded with an Inspire bracket had enamel fracture upon debonding. Most of the brackets (90% of Clarity and 95% of Inspire) debonded with pliers failed at the bracket-adhesive interface. No enamel damage was evident in any specimen when the brackets were removed with the appropriate pliers. The results indicate that the safest way to remove ceramic brackets with respect to reducing the chance of enamel damage is to use the debonding technique specifically designed for each.  相似文献   
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Abstract: Twenty-six part-time students from a variety of professional backgrounds are enrolled in the first year of a Graduate Diploma in Social Science (Drug Dependence) at the Phillip Institute of Technology in Victoria. The course is conducted under the auspices of the School of Social Work and commenced in 1984. It is argued that the graduates from this unique course could play a key role in providing personnel to fill positions in the areas of clinical work, staff development, drug education, programme development and management and research.  相似文献   
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Nuclear medicine techniques may be used to test fallopian tube patency and penile vascular inflow and outflow. Radionuclide hysterosalpingography (HSP) is a readily performed method of evaluating fallopian tube patency, and is believed to be more physiologic and functionally informative than the accepted radiologic method of contrast HSP. The test is simple to perform and interpret and offers an accurate alternative to the contrast examination. For scintigraphic evaluation of impotence, blood pool studies are most useful in assessing the integrity of arterial inflow, but may also be used to generate indices of venous leak. Washout of xenon after subcutaneous injection, in the flaccid state, has been used as a measure of baseline penile perfusion, as has intracavernosal injections in the flaccid penis. Intracavernosal xenon washout during erection seems the most useful method of testing venous integrity. Washout using technetium-99m (99mTc)-labeled red blood cells (99mTc-RBC) may emerge as a convenient alternative to the more technically difficult xenon examinations.  相似文献   
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