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61.
Objectives:Fatigue sacral fractures (FSFs) are rare and often misdiagnosed. This study presents a series of FSFs and a meticulous literature review.Methods:The present is an 11-year (2010-2021) retrospective observational study. The characteristics of all adult patients with FSF, including demographics, fracture type, treatment, history of fatigue fracture and imaging were evaluated.Results:Eight cases (6 females; 75%), suffering from 12 fractures (4 bilateral cases) with mean age=33.4 years were studied. Two patients (25%) had suffered another fatigue fracture in the past. Mean symptoms’ duration prior diagnosis was 8.5 weeks, while mean symptoms’ duration after diagnosis was 10.75. In most cases (7; 87.5%), MRI revealed the fracture. According to the Kaeding-Miller classification; five fractures (42%) were grade III, four (33%) IV and three (25%) II. All patients were treated conservatively, with rest and analgesics, while three received vitamin D and calcium. One patient, due to delayed union, was commenced on teriparatide.Conclusions:FSFs are often misdiagnosed; therefore, they should be included in the differential diagnosis for chronic low back-or-hip pain in athletes. History of other fatigue injuries seems to be a predisposing factor. It is of paramount importance to obtain advanced imaging for identifying a FSF.  相似文献   
62.
Solar cells based on nanocrystalline TiO2 sensitized by dyes that contain poly-pyridyne rings have been examined by in situ micro- and macro-Raman spectroscopy under positive and negative bias. Four modes in the low frequency range appear for nearly short-circuit conditions and are attributed to the vibrations of triiodide, bound on the oxidized form of the dye. The intensity and frequency of these modes depend on the applied potential and their behavior is correlated with characteristic regions of the current-potential curves. Our results are supported by polarized Raman experiments and basic theoretical simulations.  相似文献   
63.
We have previously derived 2 V79 clones resistant to menadione (Md1 cells) and cadmium (Cd1 cells), respectively. They both were shown to be cross-resistant to hydrogen peroxide. There was a modification in the antioxidant repertoire in these cells as compared to the parental cells. Md1 presented an increase in catalase and glutathione peroxidase activities whereas Cd1 cells exhibited an increase in metallothionein and glutathione contents. The susceptibility of the DNA of these cells to the damaging effect of H2O2 was tested using the DNA precipitation assay. Both Md1 and Cd1 DNAs were more resistant to the peroxide action. In the case of Md1 cells it seems clear that the extra resistance is provided by the increase in the two H2O2 scavenger enzymes, catalase and glutathione peroxidase. In the case of Cd1 cells the activities of these enzymes as well as of superoxide dismutases (Cu/Zn and Mn) are unaltered as compared to the parental cells. The facts that parental cells exposed to 100 μM Zn2+ in the medium exhibit an increase in metallothionein but not in glutathione and that these cells become more resistant to the DNA-damaging effect of H2O2 suggest that this protein might play a protective role in vivo against the OH radical attack on DNA.  相似文献   
64.
Abstract The persistence of toxicity of the Bacillus sphaericus 1593 binary toxin was compared when produced in B. sphaericus , inside the exosporium, or in a recombinant B. thuringiensis strain, outside the exosporium. The stability of the toxin crystal was affected by temperature and quality of the water, but not by the location of the production in the bacterial cell.  相似文献   
65.
66.
One of the most important factors affecting the quality of PCR is the choice of primers. In general, the longer the PCR product the more difficult it is to select efficient primers and set appropriate designing primers, and in general, the more DNA sequence information is available, the better the ch0ance of finding an optimal primer pair. Efficient primers can be designed by avoiding the following flaws: primer-dimer formation, self-complementarity, too lowT m of the primers, and/or their incorrect internal stability profile. Tips on subcloning PCR products, calculating duplex stability (predicting dimer formation strength), and designing degenerate primers are given.  相似文献   
67.
Abstract The size of the internal transcribed spacer (ITS) region as measured by gel electrophoresis of PCR products, amplified by primers ITS1 and ITS4, was over 800 bp for all Saccharomyces sensu stricto species, but yeasts belonging to other Saccharomyces species had a shorter ITS region, making this characteristic potentially useful in the identification of Saccharomyces isolates. The ITS product length was homogeneous within the species Saccharomyces cerevisiae .  相似文献   
68.
In a defined medium with added ethionine plus low methionine, phenylalanine, tryptophan, tyrosine, adenine, and additional methionine reversed inhibition of the enteric yeast Candida slooffii by ethionine. Isoleucine and 7-methylguanine restored half-maximal growth. Choline but not triethylcholine inhibited C. slooffii. 6-Mercaptopurine reversed ethionine inhibition and also synergistic inhibition by ethionine plus choline. Protection against ethionine by adenine plus aromatics was also evident with log-phase cells in the absence of methionine. Incorporation of ethionine-ethyl-1-(14)C by resting cells was partially inhibited by aromatic amino acids and methionine. Ethionine depressed incorporation of (3)H-phenylalanine but not of (3)H-adenine. Ethionine-resistant mutants were isolated which incorporated ethionine efficiently and degraded it to yet unidentified substances not including 5'-ethylthioadenosine. Ethionine-sensitive cells accumulated more S-adenosylethionine (SAE) than resistant mutants. Adenine was a good precursor of SAE. Radioactivity from ethionine-ethyl-1-(14)C was recovered from cell fractions of ethionine-sensitive cells with the following distribution: cold trichloroacetic acid-soluble > hot trichloroacetic acid-insoluble > lipids > deoxyribonucleic acid > ribonucleic acid. Total radioactivity recovered from ethionine-sensitive cells was twice as much as that from ethionine-resistant mutants.  相似文献   
69.
Red blood cell deformability index in diabetic retinopathy   总被引:1,自引:0,他引:1  
In order to investigate the relationship between haemorheological disturbances and diabetic microangiopathy we have studied the red blood cell deformability index (RBCD-index) by means of a filtration technique in 69 diabetics, aged 49-83 years, and in 40 non diabetic healthy controls (group A) of respective age and sex. The diabetics were classified into the following groups, according to the findings of a thorough clinical and laboratory investigation. Twenty patients (group B) were free of vascular complications, whereas 9 (group C) suffered from background retinopathy, 27 (group D) background retinopathy and ischaemic cardiopathy or peripheral arterial occlusive disease and 13 (group E) of proliferative retinopathy with diffuse micro- and macroangiopathy. The RBCD-index was significantly (P less than 0.001) decreased in diabetics with retinopathy compared to the diabetic and non diabetic controls. The lowest RBCD-index was observed in diabetics with proliferative retinopathy and in those with diffuse micro- and macrovascular complications (RBCD-index, means +/- SDM ml/min: A 0.68 +/- 0.15; B 0.64 +/- 0.08; C 0.60 +/- 0.08; D 0.49 +/- 0.09; E 0.48 +/- 0.09). These findings suggest that the RBCD is impaired in diabetics with retinopathy, especially in those with severe vascular complications, and that this abnormal rheological behavior of erythrocytes can be found even in the early stages of diabetic microangiopathy.  相似文献   
70.
The effect of exogenously added adenylate cyclase from Bordetella pertussis (strain 114) has been investigated in Y-1 mouse adrenal tumor, chinese hamster ovary (CHO) and several other cells. A partially purified adenylate cyclase was found not to enter cells but, nevertheless, produced large amounts of cAMP in the medium. We could show that this resulted from release of ATP (and not larger molecules). The ATP released by the cells could be (1) directly measured and was replenished after each change of medium; (2) was reciprocally related to the cAMP produced; and (3) was competed for by ATPases present in added serum or by hexokinase and, less effectively, by exoenzymes on the cell surface. The extent of ATP leakage varied widely between different cell lines, being marked in CHO and Y-1 adrenal cells but negligible in transformed lymphocyte lines. The uncertainty of the origin of cAMP found in media of cultured cells requires separate analysis of cell and medium cAMP and an assessment of ATP leakage.  相似文献   
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