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81.
A mixed gas-liquid chromatography column of FFAP and Apolar-7CP has excelelnt thermal stability and shows excellent characteristics for the separation of the methylesters of fatty acids from Salmonella enteritidis call wall lipids.  相似文献   
82.
Leaf development involves many complex genetic interactions,signals between adjacent cells or between more distant tissues and consequent changes in cell fate.This review describes three stages in leaf development where regulation by small RNAs have been used to modulate gene expression patterns.  相似文献   
83.
A protein-nucleic acid crosslink in 30S ribosomes   总被引:16,自引:0,他引:16  
The data indicate that probably a single 30s ribosomal protein has been crosslinked to the 3′-ribosyl terminus of 16s RNA in intact 30s ribosomes. The crosslink was made by oxidizing the 3′-ribosyl moiety of 16s RNA to a dialdehyde with NaIO4. One of the aldehyde groups generated in the oxidation reacted with an α- or ε-amino group of an adjacent protein to form a Schiff's base. The Schiff's base was reduced with NaBH4 to a stable, specific covalent crosslink between the protein and the 16s RNA molecules. The crosslinked protein was tentatively identified as S1 according to the nomenclature of Wittmann et al. (1971), Mol. Gen. Genetics 111, 327.  相似文献   
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This study examined the efficacy of behavioral strategies in alleviating pain and anxiety associated with severe orthopedic trauma. Sixty-four patients with multiple fractures were divided into four groups: (1) control, (2) attention only, (3) EMG biofeedback-assisted relaxation, and (4) audiotaped relaxation training. All were measured over at least six sessions, or as long as hospital stay permitted. Significant between group differences were found on the following: systolic blood pressure, peripheral temperature, subjective units of discomfort, state anxiety, with a trend for use of sleep medications. No differences were found on other vital signs, EMG recordings, or other medications. EMG-biofeedback relaxation and relaxation training were relatively equivalent for all measures, and little or no change was observed for those patients who received attention only or served as controls.  相似文献   
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Background  

Transmissible spongiform encephalopathy diseases are untreatable, uniformly fatal degenerative syndromes of the central nervous system that can be transmitted both within as well as between species. The bovine spongiform encephalopathy (BSE) epidemic and the emergence of a new human variant of Creutzfeldt-Jakob disease (vCJD), have profoundly influenced beef production processes as well as blood donation and surgical procedures. Simple, robust and cost effective diagnostic screening and surveillance tools are needed for both the preclinical and clinical stages of TSE disease in order to minimize both the economic costs and zoonotic risk of BSE and to further reduce the risk of secondary vCJD.  相似文献   
89.

Background  

This study evaluated whether there is a relationship between the zona pellucida birefringence (ZP-BF) intensity and the nuclear (NM) and cytoplasmic (CM) in vitro maturation of human oocytes from stimulated cycles.  相似文献   
90.
The widely used hydrophobic cannabinoid ligand CP-55,940 partitions with high efficiency into biomembranes. We studied the location, orientation, and dynamics of CP-55,940 in POPC bilayers by solid-state NMR. Chemical-shift perturbation of POPC protons from the aromatic ring-current effect, as well as 1H NMR cross-relaxation rates, locate the hydroxyphenyl ring of the ligand near the lipid glycerol, carbonyls, and upper acyl-chain methylenes. Order parameters of the hydroxyphenyl ring determined by the 1H-13C DIPSHIFT experiment indicate that the bond between the hydroxyphenyl and hydroxycyclohexyl rings is oriented perpendicular to the bilayer normal. 2H NMR order parameters of the nonyl tail are very low, indicating that the hydrophobic chain maintains a high level of conformational flexibility in the membrane. Lateral diffusion rates of CP-55,940 and POPC were measured by 1H magic-angle spinning NMR with pulsed magnetic field gradients. The rate of CP-55,940 diffusion is comparable to the rate of lipid diffusion. The magnitude of cross-relaxation and diffusion rates suggests that associations between CP-55,940 and lipids are with lifetimes of a fraction of a microsecond. With its flexible hydrophobic tail, CP-55,940 may efficiently approach the binding site of the cannabinoid receptor from the lipid-water interface by lateral diffusion.  相似文献   
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