S P Clark

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We have cloned and sequenced a human mRNA specific for mammalian T-lymphoid cells. The message was found to be expressed in human and murine T lymphoblasts, thymocytes and phytohaemagglutinin-stimulated T lymphocytes. The protein deduced from the cDNA sequence has a molecular weight of 34,938 and shows extensive similarity to the entire length of the(More)
A cDNA clone YT35 , synthesized from poly(A)+ RNA of the human T cell tumor Molt 3, exhibits homology to the variable (V), joining (J), and constant (C) regions of immunoglobulin genes. We have isolated and sequenced the germ-line V and J gene segment counterparts to YT35 from a human cosmid library, and these failed to encode 14 nucleotides of the cDNA(More)
T lymphocytes can produce mRNAs from the first or second constant region of the T-cell antigen receptor beta-chain. A 1.3-kilobase (kb) transcript encoding the mature protein contains V, J and one of the two C region sequences, but does not always contain D sequences. A 1.0-kb mRNA, found mainly in immature T cells, does not contain V sequences and can(More)
An essential property of the immune system is its ability to generate great diversity in antibody and T-cell immune responses. The genetic and molecular mechanisms responsible for the generation of antibody diversity have been investigated during the past several years. The gene for the variable (V) region, which determines antigen specificity, is assembled(More)
The humoral immune system antigen-binding proteins (immunoglobulins) are disulphide-linked heterodimers of light and heavy chains. The gene for the variable region which determines antigen specificity is assembled when one member from each of the dispersed clusters of variable (V) gene segments, diversity (D) elements (for the heavy chains only) and joining(More)
A patient with a mixed testicular germ cell tumor (choriocarcinoma, teratocarcinoma and embryonal carcinoma) that had metastasized to the lungs, cerebrum, and pineal gland is presented. The metastases had resulted in localized neurological signs and initially, on clinical grounds, a primary intracranial lesion could not be excluded. The occurrence of tumor(More)
Ligand-bridged mixed-valence ions can exist in either valence-localized (double-minimum ground potential energy surface) or valence-delocalized (single-minimum ground PE surface) form.' The determining factor is the balance between twice the initial-state/final-state electronic coupling energy (&) and the sum of the zeroth-order reorganization or trapping(More)
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