Abstract: The invention concerns a method for the modification, cloning and amplification of cDNAs which are complete at their 5′ end which is essentially characterized in that the first strand cDNA synthesis is carried out in the presence of manganese2+ ions or manganese2+ is added as an additive at a later time. The CAP structure at the 5′ end of the reversely transcribed mRNA triggers the attachment of deoxy-cytosines to the 3′ end of the cDNA with high efficiency. In a preferred embodiment a controlled ribonucleotide tailing is carried out with the aid of terminal transferase following the first strand cDNA synthesis.

Abstract: The invention concerns a method for the modification, cloning and amplification of cDNAs which are complete at their 5′ end which is essentially characterized in that the first strand cDNA synthesis is carried out in the presence of manganese2+ ions or manganese2+ is added as an additive at a later time. The CAP structure at the 5′ end of the reversely transcribed mRNA triggers the attachment of deoxy-cytosines to the 3′ end of the cDNA with high efficiency. In a preferred embodiment a controlled ribonucleotide tailing is carried out with the aid of terminal transferase following the first strand cDNA synthesis.

Abstract: The present invention concerns a process for the amplification of nucleic acids, wherein the tailing of the nucleic acid to be amplified is effected by extending the nucleic acid with ribonucleotides at its 3′ end with the aid of terminal transferase. Further, a kit for the amplification of a nucleic acid, which includes at least one ribonucleotide and terminal transferase, is provided.

Abstract: A downhole wash tool for carrying out cleaning operations in a borehole. The tool has a housing on which a plurality of flow-blocking, diverters (e.g. steel) are mounted. The diverters move between a retracted position and an extended position wherein the diverters effectively block flow around the tool. A retainer normally maintains the diverters in their retracted position when in a first position and releases the diverters when in a second position. A spring normally biases the retainer towards its first position. The retainer is hydraulically-actuated through the housing to move it towards its second position. When the cleaning operation is completed, pressure in the workstring is relaxed whereupon the spring moves the retainer back to its first position to retract the diverters.