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991.
Oral tissue samples were studied using mid-IR fiber-optic attenuated total reflectance spectroscopy and other spectral techniques. The 1745 cm(-1) band, which is assigned to the ester group (C==O) vibration of triglycerides, is a reliable marker that is present in normal tissues but absent or a weak band in malignant oral tissues. Other bands such as C--H stretching bands and the amide bands are also helpful in distinguishing malignant tissues from normal tissues. Subtraction spectra confirmed the above conclusion. In addition, Raman spectroscopic measurements were in agreement with the results observed from FTIR spectra. 相似文献
992.
993.
The synthesis of glucose oxidase and catalase by Aspergillus niger was investigated using a resting cell culture system without growth being established. Calcium carbonate induced the synthesis of both enzymes and calcium chloride inhibited it. The optimal pH for the biosynthesis of glucose oxidase and catalase was 6.0 and 5.7, respectively. The effects of other bivalent cations, reductive compounds and metabolic products on enzyme synthesis were also tested. The biosynthesis of glucose oxidase and catalase was promoted by MnCO3, thioglycolic acid, pyroracemic acid and gluconic acid. 相似文献
994.
Insights into the function of Rim protein in photoreceptors and etiology of Stargardt's disease from the phenotype in abcr knockout mice. 总被引:19,自引:0,他引:19
Rim protein (RmP) is an ABC transporter of unknown function in rod outer segment discs. The human gene for RmP (ABCR) is affected in several recessive retinal degenerations. Here, we characterize the ocular phenotype in abcr knockout mice. Mice lacking RmP show delayed dark adaptation, increased all-trans-retinaldehyde (all-trans-RAL) following light exposure, elevated phosphatidylethanolamine (PE) in outer segments, accumulation of the protonated Schiff base complex of all-trans-RAL and PE (N-retinylidene-PE), and striking deposition of a major lipofuscin fluorophore (A2-E) in retinal pigment epithelium (RPE). These data suggest that RmP functions as an outwardly directed flippase for N-retinylidene-PE. Delayed dark adaptation is likely due to accumulation in discs of the noncovalent complex between opsin and all-trans-RAL. Finally, ABCR-mediated retinal degeneration may result from "poisoning" of the RPE due to A2-E accumulation, with secondary photoreceptor degeneration due to loss of the RPE support role. 相似文献
995.
Two different Nd(NO3)3-galactitol complexes, 2Nd(NO3)3.C6H14O6.8 H2O and Nd(NO3)3.C6H14O6 have been obtained and were characterized by FT-IR and X-ray diffraction techniques. The spectral differences of the two complexes were consistent with the crystal-structure data. 相似文献
996.
Shih S Weng YM Chen S Huang SL Huang CH Chen W 《Archives of biochemistry and biophysics》2003,420(1):79-86
FT-Raman spectroscopy was employed to explore the structural changes of lens proteins in Tilapia lenses affected by dietary vitamin E supplementation. The microenvironment of major lens constituents including thiol compounds, tyrosine, and tryptophan exhibited significant change upon vitamin E treatment, while the protein secondary structure was unaltered and remained as an antiparallel beta-pleated sheet. These structures in the cortex were more susceptible to vitamin E treatment than in the nucleus. Protein sulfhydryls in the cortex were predominantly in the reduced form, while in the nucleus both the oxidized and reduced forms coexisted as evidenced by the vibrational mode of SH (2580 cm(-1)) and SS (507 cm(-1)), respectively. Both tyrosine and tryptophan were more accessible to water or more exposed in the cortex than in the nucleus. The symmetrically inverse response of vitamin E, between Raman intensity of 1090 cm(-1) and the glutathione level, was consistent with a close relationship of GSH and vitamin E in defending the lens from external insults. 相似文献
997.
Direct EPR evidence of the photo-generation of superoxide radicals (O2
–.) was obtained by using a novel spin trapping probe in spinach Photosystem II (PS II) membrane fragments. The production of O2
–. was detected by following the formation of 5-diethoxyphosphoryl-5-methyl-1-pyrroline-N-oxide (DEPMPO) superoxide adducts (DEPMPO-OOH). The inhibition of O2
–. formation by 3-(3,4-dichlorophenyl) -1,1-dimethylurea (DCMU) and the 77 K fluorescence spectrum indicated that O2
–. were generated from PS II, not from PS I. The inhibition of O2
–. formation by DCMU also suggested that O2
–. were generated from the QBbinding site, not at a site prior to DCMU blockage. The extrinsic proteins and Mn are very important to eliminate O2
–., showing that the oxygen-evolving system is involved in O2
–. removal rather than production.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
998.
Lai YL Yu YL Centeno RF Weng CJ 《Plastic and reconstructive surgery》2003,112(1):302-8; discussion 309-11
Since the 1980s, many patients have benefited from the use of the transverse rectus abdominis musculocutaneous (TRAM) flap for postmastectomy reconstruction. In addition to cancer reconstruction, this technique has recently been used to treat patients with breast implant intolerance and for reconstruction after siliconoma resection. However, physicians and patients alike believe that such an extensive procedure should not be used for aesthetic purposes, and to the authors' knowledge, no study has been reported on the use of pedicled TRAM flaps for aesthetic augmentation mammaplasty. In the past several years, a number of the authors' patients have requested simultaneous breast augmentation and abdominoplasty. These patients objected to the use of prosthetic implants because of potential complications such as implant failure, capsular contracture, wrinkling, and palpability. Therefore, from 1995 to 2000, the authors performed 14 cases of bilateral breast augmentation with deepithelialized, pedicled TRAM flaps. In this series, the donor-site complication rate was similar to that of the traditional TRAM flap. Surprisingly, no cases of complete or partial flap loss were clinically detected. The only complaints were pedicle bulges at the costal margins. These patients were all extremely satisfied with the results. It was concluded that the TRAM flap is safe for augmentation in a subset of carefully selected women with hypoplastic or atrophic breasts. The authors discuss patient selection, technique, and their experience with this method of breast augmentation. 相似文献
999.
Fine mapping of the rice thermo-sensitive genic male-sterile gene <Emphasis Type="Italic">tms5</Emphasis> 总被引:10,自引:0,他引:10
Wang YG Xing QH Deng QY Liang FS Yuan LP Weng ML Wang B 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(5):917-921
AnnongS-1, a thermo-sensitive genic male-sterile (TGMS) rice line, has a new TGMS gene. Genetic analysis indicated that the sterility of AnnongS-1 was controlled by a single resessive gene named tms5. In our previous studies based on an F2 population from the cross between AnnongS-1 and Nanjing11, tms5 was mapped on chromosome 2. Recently, a RIL (recombinant inbred line) population from the same cross was developed and used for the fine mapping of the tms5 gene. Molecular marker techniques combined with BSA (bulked segregant analysis) were used. As a result, two AFLP markers (AF10, AF8), one RAPD marker (RA4), one STS marker (C365-1), one CAPs marker (G227-1) and four SSR markers (RM279, RM492, RM327, RM324) were found to be closely linked to tms5 gene. The DNA sequences of the RFLP marker of C365 and G227 were found in GenBank, and on the basis of these sequences, many primers were designed to amplify the two parents and their RIL population plants. Finally, the tms5 gene was mapped between STS marker C365-1 and CAPs marker G227-1 at a distance of 1.04 cM from C365-1 and 2.08 cM from G227-1.Communicated by H.F. LinskensY.G. Wang and Q.H. Xing contributed equally to this contribution. 相似文献
1000.
Weng L Van Bockstaele DR Wauters J Van Marck E Plum J Berneman ZN Merregaert J 《The Journal of biological chemistry》2003,278(21):19164-19170
Chondrolectin (CHODL) is a novel type I transmembrane protein containing one carbohydrate recognition domain (CRD) of C-type lectins. Recently, data base searching revealed a variant of CHODL (AK022689) with a different 5' leader sequence derived from a new putative upstream alternative promoter (P2). The P2 promoter gives rise to at least three additional alternatively spliced isoforms, designated as CHODLf, CHODLf Delta E, and CHODL Delta E. Of all variants, the alternative exon E-splicing isoforms (CHODLf Delta E/CHODL Delta E) are expressed exclusively in the T lymphocyte lineage and are regulated during T lymphopoiesis. Peripheral T lymphocytes demonstrated a unique exon E-splicing pattern in comparison with end maturation stage thymocytes, suggesting its association with the post-thymic maturation of T cells. Since exon E encodes the transmembrane domain of CHODL, the exon E-skipping variant results in a non-transmembrane domain-containing isoform (CHODLf Delta E/CHODL Delta E) terminating in the QDEL sequence, thus suggesting different functional attributes of CHODL isoforms during the development of T cells. Double label immunofluoresence experiments demonstrated that the transmembrane-containing isoform (CHODLf) colocalizes with rBet1 to the endoplasmic reticulum-Golgi apparatus. In summary, this study describes the molecular characterization of novel members of the chondrolectin family associated with T cell maturation and a subcellular localization of CHODLf in the endoplasmic reticulum-Golgi apparatus. 相似文献