Abstract: The present application discloses an intestine-targeted drug delivery composition, comprising in sequence, from inside to outside, (1) a microsphere core and a pH-independent sustained-release layer containing an active ingredient, or a microsphere containing an active ingredient and a pH-independent sustained-release layer, or a microsphere containing an active ingredient and a pH-independent sustained-release material, (2) a pH-dependent coating layer, and (3) a time-dependent pulsatile controlled-release layer. The intestine-targeted drug delivery composition of the present application delivers the active ingredient to intestinal tissues (especially colon tissue) for release, reduces the systemic blood concentration of the active ingredient, and improves the pharmacokinetic characteristics and concentration of the active ingredient in intestinal tissues. The composition is suitable for treating intestinal diseases, such as inflammatory bowel diseases including Crohn's disease and ulcerative colitis.

Abstract: A molecular marker for the selection and breeding of fine-wool sheep is disclosed. The marker is an STR marker comprising a (CA)n repeat core sequence, with n between 5 and 24 that can be obtained by PCR amplification of genomic DNA of sheep using the primers shown in SEQ ID NO: 1 and SEQ ID NO: 2 and sequencing the PCR product. When n is 17 or 18, a sheep is a fine-wool breed, and when n is 23 or 24, a sheep is a non-fine-wool breed. When the CA repeat is discontinuous, i.e., divided into two segments (e.g., 12+11 or 13+11) separated by two bases TA or GA, a sheep is a hybrid breed of fine-wool sheep and non-fine-wool sheep. Use of the marker provides methods of identifying of fine-wool sheep breeds, and efficient and accurate selection of fine-wool sheep or the hybrid offspring of fine-wool sheep for breeding.