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51.
The spv regulon of Salmonella dublin is essential for virulence in mice. SpvR, a LysR-type regulator, induces the expression of the spvABCD operon and its own expression in the stationary phase of bacterial growth and in macrophages. We constructed fusion proteins to the maltose-binding protein (MBP) and a His tag peptide (His) to overcome the insolubility and to facilitate purification of SpvR. We demonstrated that both fusion proteins, MBP-SpvR and His-SpvR, were able to induce spvA expression in vivo. MBP-SpvR was produced as soluble protein, whereas His-SpvR was only marginally present in the soluble cell fraction. Affinity chromatography resulted in at least 95% pure MBP-SpvR protein and in an enrichment of His-SpvR. Gel mobility shift assay revealed that the SpvR fusion proteins were able to bind to 125-and 147-bp DNA fragments of the spvA and spvR promoter regions, respectively. DNase I footprint experiments showed that the fusion proteins protected DNA regions of 54 and 50 bp within the spvA and spvR promoter regions, respectively. 相似文献
52.
STUDY DESIGN: In a retrospective study, the long-term results of translaminar facet screw fixation of the lumbar and lumbosacral spine are reviewed. OBJECTIVES: To evaluate the clinical results, fusion rates and complications of this posterior fusion technique in various conditions of the lumbar spine. SUMMARY OF BACKGROUND DATA: Posterior fusion of the lumbar and lumbosacral spine is one of the possible methods to relieve pain and eliminate instability in degenerative conditions. Data in the literature support the use of internal fixation to optimize the rate of fusion. METHODS: Posterior lumbar and lumbosacral fixation with translaminar screws and fusion in 173 patients with degenerative changes with or without compressive syndromes including failed back syndromes, monosegmental hypermobilities, and posttraumatic conditions were investigated. Fixation and fusion with translaminar screws was performed in 57% monosegmentally, in 40% across two segments and in 2% over three segments. Decompressive surgery was performed in addition in 52% and nucleotomy in 30% of the cases. Clinical and radiologic assessment with flexion/extension x-rays was performed in 145 (83%) patients by two independent orthopedic surgeons. After an average follow-up of 68 months (range, 52-83). RESULTS: Ninety-four percent of the patients showed solid bony fusion in the radiologic follow-up. Loosening of the screws was noted in 3%, and two screws were broken without apparent motion on the functional x-rays. Pain scores decreased from 7.6 before surgery to 2.9 after surgery on a 10-point pain scale. The results were further analyzed according to Stauffer and Coventry with 99 good results, 70 satisfactory results, and 4 bad results. CONCLUSIONS: Translaminar screw fixation offers an immediate postoperative stability of the lumbar and lumbosacral spine and enhances fusion. In the present series no neurologic complications were noted. It represents a useful and inexpensive technique for short segment fusion of the nontraumatic lumbar and lumbosacral spine. 相似文献
53.
Maurus Biedermann Konrad Grob Carlo Mariani Joachim P. Schmidt 《European Food Research and Technology》1996,202(3):199-204
Adulteration of expensive edible oils, such as olive oil, often involves desterolized oils in order to render the adulteration undetectable. Sunflower oil contains characteristic Δ7-sterols, which are readily removed upon strong bleaching. It is shown that these Δ7-sterols do not primarily dehydrate (as do Δ5-sterols), but isomerize to Δ8(14)- and Δ14-sterols. These compounds can be analysed by LC on silica gel or GC on capillary columns with stationary phases of intermediate to high polarity. 相似文献
54.
A Gül U Ozbek C Oztürk M Inan? M Koni?e T Oz?elik 《Canadian Metallurgical Quarterly》1996,35(11):1178-1180
We investigated the prevalence of the coagulation factor V gene G1691A mutation in 64 patients with Beh?et's disease (BD) and in 107 apparently healthy individuals. The mutation was present in the heterozygous state in 37.5% of the patients with a history of deep vein thrombosis (12/32) and in 9.4% of the patients without any thrombotic event (3/32). Eleven healthy individuals were also heterozygous for the mutation (10.3%). The prevalence of the mutation in BD patients with and without thrombosis was significantly different (P = 0.0079). We conclude that the factor V gene mutation may play a major role in the development of venous thrombosis in BD. 相似文献
55.
Following a contamination of the animal food chain in Belgium with PCBs, we investigated if there was a link between the presence of PCBs and the mineral oil content. The concentrations of mineral oil hydrocarbons in samples highly contaminated with PCBs were identical with those observed in samples with very low concentrations of PCB collected from non-contaminated farms or supermarkets. We concluded that the introduction of PCBs in the animal food chain was done by the use of pure transformer oil and not by waste oils (used edible, hydraulic or motor oils) collected at the recycling centres. The concentrations of mineral oil were lower than samples collected and analysed in Switzerland during the summer of 1999 when relatively high levels were measured. 相似文献
56.
An optimised off-line SPE–GC–FID method based on the use of silver-silica gel was developed for the determination of mineral oil saturated hydrocarbons (MOSH) in vegetable oils, including olive pomace oil. The method is specific in not including the aromatic hydrocarbons. The performance of different silica gels (untreated, activated and treated with silver nitrate) was compared in terms of capacity to retain fat and retention of interfering olefins present in particularly large amounts in refined olive oils. A coefficient of variation of 9% was obtained performing six replicate analyses of an extra virgin olive oil fortified with an amount of MOSH near the estimated LOQ (15 mg/kg). Recoveries were close to 100%. The use of activated aluminium oxide as an additional tool to eliminate interference by endogenous long-chain n-alkanes, is discussed. 相似文献
57.
D Grob 《Canadian Metallurgical Quarterly》1996,25(6):554-557
Radicular pain is a common feature in day-to-day clinical practice. Only a small percentage of patients with persistent pain and/ or neurological deficit need surgical decompression. Exact anatomical localization of the decompressive agent and the correlation of clinical symptoms and radiological findings are mandatory. In most cases, surgery is performed by an anterior approach; by which the causative agent is removed. In cases with narrowing of the neural foramen total resection of the uncus is indicated. Additional fusion supports the physiological cervical lordosis. 相似文献
58.
Konrad Grob Mauro Lanfranchi Cario Mariani 《Journal of the American Oil Chemists' Society》1990,67(10):626-634
The analysis of the fatty alcohols, the wax esters, the free and the esterified sterols, as well as that of minor components
provides a wealth of information about the quality of an oil or fat, its pretreatment and admixture with other oils. Some
results obtained by an easy, nearly fully-automated method are shown for olive oils. More specific information is obtained
than by the previous saponification methods. 相似文献
59.
S Leyvraz N Ketterer P Vuichard V von Fliedner F Lejeune P Schneider JP Grob F Bachmann 《Canadian Metallurgical Quarterly》1993,85(23):1962-1964
60.
Konrad Grob Anna Artho Carlo Mariani 《European Journal of Lipid Science and Technology》1992,94(10):394-400
Raffination of edible oils and fats, i.e. bleaching with earth or charcoal as well as deodoration, can be determined by the analysis of dehydroxylation products of sterols and isomerization products of squalene. These olefinic degradation products are isolated from the rest of the oil by LC on silica gel and on-line transfer to GC. Sample preparation consists of preparing a 20% solution of the oil. Nearly half of the “extra virgin” olive oils analyzed contained such products, but concentrations were too low for assuming admixture of regularly refined oils. However, many other oils advertized as non-refined turned out to have been treated beyond declaration. 相似文献