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Metabolism of Choline Chloride and Its Analogs in Wheat Seedlings   总被引:5,自引:0,他引:5  
The incorporation rate of choline chloride and allylcholinebromide into wheat protoplasts were rapid compared with theincorporation rate of benzylcholine bromide. Choline chloridewas metabolized via two pathways: choline betaine and choline phosphorylcholine phos-phatidylcholine. Allylcholine bromidewas metabolized via only one pathway: allylcholine phosphorylallylcholine phosphatidylallylcholine, and benzylcholine bromide was notmetabolized at all. These results suggest that the stimulationof photosynthesis (Hyeon et al. 1988) by these compounds iscaused directly by these choline analogs and not by their metabolites. (Received June 29, 1989; Accepted October 20, 1989)  相似文献   
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Sequence and diversity of rabbit T-cell receptor gamma chain genes   总被引:2,自引:2,他引:0  
The nucleotide sequences of one constant (C), six variable (V), and two joining (J) gene segments coding for the rabbit T-cell receptor gamma chain (Tcrg) were determined by directly sequencing fragments amplified by the cassette-ligation mediated polymerase chain reaction. The Tcrg-C gene segment did not encode a cysteine residue for connection to the Tcr delta chain in the connecting region, and two variant forms of the Tcrg-C gene segment were generated by alternative splicing, like the human Tcrg-C2 gene. Five of six rabbit Tcrg-V gene segments belonged to the same family and displayed similarity to five productive human Tcrg-V1 family genes as well as the mouse Tcrg-V5 gene. The remaining rabbit Tcrg-V gene segment displayed similarity to the human Tcrg-V3 gene. Both rabbit Tcrg-J gene segments displayed similarity to the human Tcrg-J2.1 and 2.3, respectively. These findings suggested that the genomic organization of rabbit Tcrg genes is more similar to that of human than of mouse Tcrg genes.The nucleotide sequence data reported in this paper have been submitted to the GSDB, DDBJ, EMBL, and NCBI nucleotide sequence databases and have been assigned the accession numbers D38134-D38144 and D42090  相似文献   
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Abstract

Novel 1,3-oxathiolanyl pyrimidine nucleosides with 5-hydroxymethyl substituent were synthesized starting from d-mannose and evaluated for antiviral activities against HIV-1, HSV type 1,2 and HCMV.  相似文献   
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Background

Interferon-γ release assays such as the QuantiFERON-TB Gold In-Tube Test (QFT-GIT) are designed to detect Mycobacterium tuberculosis infections, whether latent or manifesting as disease. However, a substantial number of persons with culture-confirmed tuberculosis (TB) have negative QFT-GITs. Information on host factors contributing to false-negative and indeterminate results are limited.

Methods

A multicenter retrospective cohort study was performed with 1,264 culture-confirmed TB patients older than 18 years who were subjected to the QFT-GIT at one of the six hospitals between May 2007 and February 2014. Patients with human immunodeficiency virus infection were excluded. Clinical and laboratory data were collected in South Korea.

Results

Of all patients, 87.6% (1,107/1,264) were diagnosed with pulmonary TB and 12.4% (157/1,264) with extrapulmonary TB. The rate of negative results was 14.4% (182/1,264). The following factors were highly correlated with false-negative results in the QFT-GIT: advanced age (age ≥ 65 years, odds ratio [OR] 1.57, 95% confidence interval [CI] 1.03–2.39), bilateral disease as determined by chest radiography (OR 1.75, 95% CI 1.13–2.72), malignancy (OR 2.42, 95% CI 1.30–4.49), and lymphocytopenia (total lymphocyte count < 1.0 × 109/L, OR 1.86, 95% CI 1.21–2.87).

Conclusions

Consequently, QFT-GIT results need to be interpreted with caution in patients with these host risk factors such as the elderly, bilateral disease on chest radiography, or malignancy, or lymphocytopenia.  相似文献   
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