Biomedical subjects

Xizhi Zeng

Publications and source records attributed to Xizhi Zeng.

3 recordsLinked to original sources

PubMed2005

Realization of a decoherence-free subspace using multiple quantum coherences.

This Letter presents a two-dimensional nuclear magnetic resonance (NMR) approach for constructing a two-logical-qubit decoherence-free subspace (DFS) by using four multiple-quantum coherences of a CH3 spin system as logical qubits. The three protons in this spin system are magnetically equivalent and can only be used as a single qubit in one-dimensional NMR. We have experimentally demonstrated that our DFS can protect against more types of decoherences than those of the one composed of four noisy physical qubits all with different chemical shifts. This idea may provide new insights into extending qubit systems in the sense that it effectively utilizes the magnetically equivalent nuclei.

Journal Article↗

PubMed2005

Probing the alkyl ligands on silylated mesoporous MCM-41 using hyperpolarized 129Xe NMR spectroscopy.

Variable-temperature hyperpolarized (HP) 129Xe NMR spectroscopy has been employed to characterize surface properties of mesoporous MCM-41 modified by silylation treatment. The characteristic chemical shifts responsible for Xe-surface interactions exhibit strong correlations with both the surface coverage and chain length of the grafted alkylsilanes. Consequently, the deshielding medium contribution due to individual alkyl ligand can be deduced based on the group contribution analysis revealing the potential use of HP 129Xe NMR for probing the surface properties of organic-functionalized porous materials.

Journal Article↗

PubMed2003

Relationship between expression of somatostatin receptors subtype 2 mRNA and estrogen and progesterone receptors in breast cancer.

OBJECTIVES: To observe the expression of somatostatin receptor subtype 2 (SSTR2) mRNA, and investigate the relationship between the expression of SSTR2 mRNA and the expressions of estrogen and progesterone receptors (ERs and PRs) in benign and malignant breast tissues. METHODS: Samples from a total of 23 breast carcinomas, 16 mammary hyperplasias, and 9 mammary fibroadenomas were analyzed. SSTR2 mRNA expression was examined by in situ hybridization using multiphase oligoprobes. ER and PR expressions were detected by immunohistochemical staining. A computerized image analysis system was utilized to estimate the relative content of SSTR2 mRNA. RESULTS: The rate of expression (87.0%) and relative content (0.47) of SSTR2 mRNA in breast cancer were higher than those in benign breast tissue (64%, 0.26) (P < 0.05). SSTR2 mRNA expression was closely correlated with ER and PR expressions in breast cancer (P < 0.05). SSTR2 mRNA was also positively correlated with ER expression in benign breast tissues. CONCLUSIONS: SSTR2 mRNA expression is higher or in benign breast tissues than in malignant ones. There is a significant positive correlation between SSTR2 mRNA and ER and PR expressions. Combined antiestrogen and somatostatin analogue in treatment of ER-positive breast cancers should be further investigated.

Breast Diseases↗