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941.
Peroneal flap for reconstruction in the extremity: preliminary report   总被引:3,自引:0,他引:3  
The peroneal flap has many advantages, such as thin subcutaneous tissue, availability of a large-diameter artery and vein for anastomosis, a long pedicle, and freely designed size and shape. This technique is introduced because it has many outstanding features that allow it to be used to meet a variety of specific needs, such as a free peroneal flap, a peroneal island flap, a free vascularized fibular graft with skin, and a monitoring flap in free vascularized fibular grafts. We have found the peroneal flap to be especially useful.  相似文献   
942.
943.
BackgroundImmunosuppressed states may predispose patients to development of acute brain injury during times of critical illness. Lymphopenia is a non-specific yet commonly used bedside marker of immunosuppressed states.MethodsWe examined whether lymphopenia would predict development of acute brain dysfunction (delirium and/or coma) in 518 patients enrolled in the Bringing to Light the Risk Factors and Incidence of Neuropsychological Dysfunction in ICU Survivors (BRAIN-ICU) study in medical and surgical ICUs of a tertiary care, university-based medical center. Utilizing proportional odds logistic regression and Cox proportional hazards survival analysis, we assessed the relationship between pre-enrollment lymphocytes and subsequent cognitive outcomes including delirium- and coma-free days (DCFDs) and 30-day mortality.ResultsThere were no statistically significant associations between lymphocytes and DCFDs (p = 0.17); additionally, the relationship between lymphocytes and mortality was not statistically significant (p = 0.71). Among 259 patients without history of cancer or diabetes, there was no statistically significant association between lymphocytes and DCFDs (p = 0.07).Conclusionlymphopenia, a commonly used bedside marker of immunosuppression, does not appear to be a marker of risk for acute brain injury (delirium/coma) or 30-day mortality in general medical/surgical ICU patients.  相似文献   
944.
Photosynthesis Research - Experimental evolution is a powerful tool for clarifying phenotypic and genotypic changes responsible for adaptive evolution. In this study, we isolated acid-adapted...  相似文献   
945.
Abstract

6,3′-Methanothymidine, a thymidine analogue conformationally fixed by the 6,3′-methano-bridge, was synthesized by the sequence of condensation of a ribbofuranos-3-ulose and a pyrimidinylmethyllithium, intramolecular glycosylation, 2′-deoxygenation, and final deprotection.  相似文献   
946.
Abstract

Human methylpurine N-glycosylase (MPG) activity was investigated by monitoring abasic (AP) sites resulting from removal of alkylated bases. The amount of AP sites in MMS-treated HeLa cells transiently increased at 3 h, then gradually decreased to 40% at 24 h. The presence of adenine, an inhibitor of AP endonucleases, in the repair incubation of MMS-treated cells induced moderate accumulation of AP sites, suggesting inhibition of the activities of MPG as well as AP endonucleases by adenine metabolites.

  相似文献   
947.
SDS-PAGE is one of the most powerful experimental techniques used for the separation of proteins, and most proteins are separated according to their molecular size by this technique. However, exceptional proteins showing abnormal behavior in SDS-PAGE gels are known to exist. Thermal aggregation, rarely observed with membrane proteins, is one of the exceptional behaviors of proteins during SDS-PAGE, but detailed characterization of this aggregation has not yet been achieved. In the present study, we found that a putative membrane protein, TMEM45B, very clearly showed properties of thermal aggregation when it was expressed in COS7 cells and subjected to SDS-PAGE. We dissected the region of TMEM45B responsible for this aggregation, and found that of the seven putative transmembrane domains, a region comprising the 4th to 7th ones was essential for the thermal aggregation properties. We also demonstrated that these transmembrane domains, 4th to 7th, of TMEM45B conferred thermal aggregation properties on other proteins, by fusing this amino acid sequence to target proteins. The molecular mechanism causing thermal aggregation by TMEM45B is still uncertain, but TMEM45B could be utilized as a nice model to show clear thermal aggregation in SDS-PAGE gels.  相似文献   
948.
VAMP7 or tetanus neurotoxin-insensitive vesicle- associated membrane protein (TI-VAMP) has been proposed to regulate apical transport in polarized epithelial cells, axonal transport in neurons and lysosomal exocytosis. To investigate the function of VAMP7 in vivo, we generated VAMP7 knockout mice. Here, we show that VAMP7 knockout mice are indistinguishable from control mice and display a similar localization of apical proteins in the kidney and small intestine and a similar localization of axonal proteins in the nervous system. Neurite outgrowth of cultured mutant hippocampal neurons was reduced in mutant neurons. However, lysosomal exocytosis was not affected in mutant fibroblasts. Our results show that VAMP7 is required in neurons to extend axons to the full extent. However, VAMP7 does not seem to be required for epithelial cell polarity and lysosomal exocytosis.  相似文献   
949.
The gene named bciD, which encodes the enzyme involved in C7-formylation in bacteriochlorophyll e biosynthesis, was found and investigated by insertional inactivation in the brown-colored green sulfur bacterium Chlorobaculum limnaeum (previously called Chlorobium phaeobacteroides). The bciD mutant cells were green in color, and accumulated bacteriochlorophyll c homologs bearing the 7-methyl group, compared to C7-formylated BChl e homologs in the wild type. BChl-c homolog compositions in the mutant were further different from those in Chlorobaculum tepidum which originally produced BChl c: (31 S)-8-isobutyl-12-ethyl-BChl c was unusually predominant.  相似文献   
950.
Nudix hydrolases are widely distributed in all kingdoms of life and have the potential to hydrolyze a wide range of organic pyrophosphates, including nucleoside di- and triphosphates, nucleotide coenzymes, nucleotide sugars, and RNA caps. However, except for E. coli MutT and its orthologs in other organisms that sanitize oxidized nucleotides to prevent DNA and RNA mutations, the functions of Nudix hydrolases had largely remained unclear until recently, because many members of this enzyme family exhibited broad substrate specificities. There is now increasing evidence to show that their functions extend into many aspects of the regulation of cellular responses. This review summarizes current knowledge on the molecular and enzymatic properties as well as physiological functions of Arabidopsis Nudix hydrolases. The information presented here may provide novel insights into the physiological roles of these enzymes in not only plant species, but also other organisms.  相似文献   
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