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61.
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Sixteen healthy adults had serial studies of delayed-type skin test reactivity and in vitro lymphocyte blastogenesis to several antigens over a period of 7 months. In many subjects blastogenesis varied broadly from month to month without apparent cause. Responses to all antigens usually increased or decreased together on sequential testing. Blastogenesis to coccidioidin appeared to result largely from cross-reaction with histoplasmin. Humoral factors were not demonstrably responsible for these changes. Blastogenesis rose consistently and non-specifically in subjects following revaccination to vaccinia virus. These studies reflect the lymphocyte blastogenesis reaction as a dynamic equilibrium, subject to spontaneous variation, and responding non-specifically to stimuli such as vaccination. Whatever the causes for these changes, it is clear that serial determinations of blastogenesis response to various antigens do not carry the apparent consistency of the skin test response to that antigen, and single tests must be cautiously interpreted. 相似文献
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Cardiovascular regulatory neurons of the ventral medulla and pons are thought to have an important role in the mediation of trigeminal nociception-induced reflex cardiovascular responses. However, the neural pathways that link the spinal trigeminal nucleus with ventral medullary and pontine autonomic cell groups are poorly understood. The present study utilized injections of the highly sensitive anterograde tracer substance biotinylated dextran combined with immunocytochemistry for tyrosine hydroxylase, the synthesizing enzyme for catecholamines, to investigate the distribution and morphology of projections from the spinal trigeminal subnucleus caudalis to ventral medullary and pontine catecholaminergic cell groups. Injection of biotylinated dextran into the dorsal subnucleus caudalis produced dense anterograde labeling in dorsal regions of the medullary and pontine reticular formation including the dorsal medullary reticular field, the parvicellular reticular field, and the parvicellular reticular field pars anterior. In the ventral medullary and pontine reticular formation, light anterograde labeling tended to be distributed in close proximity to the distal dendrites of catecholaminergic neurons located in the C1, A1, and A5 regions. Injections of anterograde tracer into the dorsal medullary reticular field produced dense anterograde labeling in the ventral medullary and pontine reticular formation. Numerous terminal-like varicosities were observed in close proximity to catecholaminergic neurons located in the C1, A1, and A5 regions. These data suggest that trigeminal pain-induced reflex cardiovascular responses involve indirect projections that terminate in the dorsal medullary and pontine reticular formation before reaching ventral medullary and pontine catecholaminergic cell groups known to be involved in cardiovascular regulation. 相似文献
66.
LA Durnov BM Belkina VG Poliakov GV Goldobenko IV Glekov 《Canadian Metallurgical Quarterly》1996,(10):28-33
A comprehensive programme was developed for the treatment of uni- and bilateral retinoblastoma in children with due regard to the disease stage by the TNM system. The use of the current sources of teletherapy and cyclic polychemotherapy expanded indications for organ-saving therapy at most common stages. Treatment by the program was performed in 202 patients, including 125 children with unilateral damage and 77 with bilateral damage. An attempt made treat 140 (75%) children at the first stage. More than 70% of cases were diagnosed as having disease stage T3 in one or two stage, while such patients underwent ocular enucleation. A complete or partial (more than 50%) tumor regression without signs of its progression for 2 years or more was achieved in 62% of cases. At the first stage of therapy, conservative therapy insignificantly affected the children's longevity in uncomplicated cases, which is particularly important in bilateral involvement, while this preserved the organ of vision in more than half the patients (62%). Five-year survival was 92 and 82% in unilateral retinoblastoma surgically treated and untreated, 83 and 84%, respectively. Adequate multimodality treatment brought about low incidence rates of recurrence and metastasis (10%) in conservative therapy and 7.7% among all patients. 相似文献
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The authors show that intensification of peloid therapy, i.e. more frequent procedures, in patients with pulmonary diseases imposes additional load on the regulatory systems: vegetative, cardiovascular, immune. Moderate balneological reactions become more frequent, therapeutic results worsen. How to correct the above negative effects is proposed. 相似文献
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MJ Reardon TD Hedrick GV Letsou HJ Safi R Espada JC Baldwin 《Canadian Metallurgical Quarterly》1997,64(5):1480-1482
Chronic traumatic aneurysm of the thoracic aorta is an unusual occurrence. Previously, arteriography was performed on all patients seen in our institution with this entity to allow confirmation of the diagnosis and anatomic delineation for operation. A case of chronic traumatic aneurysm of the distal descending aorta discovered on a routine chest roentgenogram and evaluated with chest computed tomographic scanning with three-dimensional reconstruction is presented. It is our belief that not all thoracic aneurysms require arteriography, and improved methods of computed tomographic scanning allow adequate diagnosis and anatomic delineation with decreased morbidity and cost. 相似文献
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The Mycobacterium tuberculosis 38-kDa protein antigen is one of the secreted immunodominant antigens showing high immunogenicity at B-cell and T-cell levels. Although monoclonal antibodies to this antigen have been produced, specific polyclonal antisera is required for standardization of specific immunodiagnostic assays. This protein has been overexpressed and purified from recombinant Escherichia coli using an inducible vector system. During each stage of expression and purification, the recombinant protein was used to immunize mice and rabbits by several methods: 1) as overexpressed protein present as inclusion bodies in recombinant E. coli; 2) embedded in a polyacrylamide gel; 3) fixed to a solid-phase nitrocellulose membrane and 4) emulsified with an adjuvant. All strategies yielded specific antisera as determined by enzyme-linked immunosorbent assay (ELISA) and immunoblot analyses. The results obtained, both quantitative (ELISA) and qualitative (immunoblot) demonstrate that the purified recombinant antigen retains its antigenicity and immunogenicity throughout the various steps in the process of expression and purification and serves as a potent antigen for production of specific antisera to be used in immunoassays. 相似文献