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101.
We have already demonstrated (Stojanovic et al., 2009) a connection between tetanus toxoid (TTd) hyperimmunization and the induction of anti-phospholipid syndrome (APS) in BALB/c mice. Here we show that C57BL/6 mice subjected to an identical procedure do not exhibit any like pathology attributable to anti-phospholipid antibodies; we explain that this absence results from idiotypic connectivity. Six groups of C57BL/6 mice were hyperimmunized with TTd in aluminum hydroxide or glycerol, with or without pretreatments. Pretreated mice had been injected with polyclonal or nonspecific immune stimulators, such as complete Freund's adjuvant (CFA) or glycerol. The epitope specificity of induced antibodies was tested by indirect ELISA using a tetanus toxoid immunogen and these autoantigens: phospholipids, gangliosides, laminin. Idiotypic connectivity was tested by competitive ELISA and gauged from the degree to which the interaction of idiotypic/anti-idiotypic complementary antibodies was inhibited in the presence of immunized sera antibodies. Higher idiotypic connectivity was noted amongst pretreated mice. There was a positive correlation between higher connectivity and autoantibody levels that acted to favor the participation of natural autoantibodies in the inhibitory process. We conclude that idiotypic connectivity plays a protective role in immunization-induced autoimmunity.  相似文献   
102.
This study aimed to identify the main components of an essential oil produced from leaves of Ambrosia trifida and to evaluate its potential allelopathic effect on seed germination and seedling growth of lettuce, watermelon, cucumber and tomato. The essential oil was obtained by hydrodistillation and characterized chemically by gas chromatography (GC) coupled with both mass spectrometry (MS) and flame ionization detector (FID). Total 69 compounds were identified, with limonene (20.7 %), bornyl acetate (15.0 %), borneol (14.7 %) and germacrene D (11.6 %) as the major components. The working solutions of the essential oil emulsified with Tween 20 and dissolved in distilled water were prepared at four concentration levels (0.01, 0.1, 0.5 % and 1 %, v/v). The results obtained showed that increase in essential oil concentration leads to decrease in seed germination, as well as shoot and radical length of lettuce, watermelon, cucumber and tomato. The obtained data revealed a highly significant effect (p<0.05) between control and 1 % and 0.5 % oil concentrations in all treatments. The essential oil of A. trifida exhibited more powerful phytotoxic effects on lettuce, watermelon and tomato than on cucumber regarding germination and early seedling growth.  相似文献   
103.

Objective

Although surgical-site infection (SSI) rates are advocated as a major evaluation criterion, the reproducibility of SSI diagnosis is unknown. We assessed agreement in diagnosing SSI among specialists involved in SSI surveillance in Europe.

Methods

Twelve case-vignettes based on suspected SSI were submitted to 100 infection-control physicians (ICPs) and 86 surgeons in 10 European countries. Each participant scored eight randomly-assigned case-vignettes on a secure online relational database. The intra-class correlation coefficient (ICC) was used to assess agreement for SSI diagnosis on a 7-point Likert scale and the kappa coefficient to assess agreement for SSI depth on a three-point scale.

Results

Intra-specialty agreement for SSI diagnosis ranged across countries and specialties from 0.00 (95%CI, 0.00–0.35) to 0.65 (0.45–0.82). Inter-specialty agreement varied from 0.04 (0.00–0.62) in to 0.55 (0.37–0.74) in Germany. For all countries pooled, intra-specialty agreement was poor for surgeons (0.24, 0.14–0.42) and good for ICPs (0.41, 0.28–0.61). Reading SSI definitions improved agreement among ICPs (0.57) but not surgeons (0.09). Intra-specialty agreement for SSI depth ranged across countries and specialties from 0.05 (0.00–0.10) to 0.50 (0.45–0.55) and was not improved by reading SSI definition.

Conclusion

Among ICPs and surgeons evaluating case-vignettes of suspected SSI, considerable disagreement occurred regarding the diagnosis, with variations across specialties and countries.  相似文献   
104.
The possibilities of parallel lactic acid and biomass production in batch and fed-batch fermentation on distillery stillage from bioethanol production were studied. The highest lactic acid yield and productivity of 92.3 % and 1.49 g L?1 h?1 were achieved in batch fermentation with initial sugar concentration of 55 g L?1. A significant improvement of the process was achieved in fed-batch fermentation where the concentration of lactic acid was increased to 47.6 % and volumetric productivity for 21 % over the batch process. A high number of Lactobacillus rhamnosus ATCC 7469 viable cells of 109 CFU ml?1 was attained at the end of fed-batch fermentation. The survival of 92.9 % of L. rhamnosus cells after 3 h of incubation at pH 2.5 validated that the fermentation media remained after lactic acid removal could be used as a biomass-enriched animal feed thus making an additional value to the process.  相似文献   
105.
New polymeric copper(II) complexes with two tridentate ONS thiosemicarbazone ligands containing substituted pyrazolone moiety were synthesized and characterized by means of spectroscopic, electrochemical and crystallographic techniques. While both ligands exist as different tautomers in the solid state and DMSO-d6 solution, Cu(II) ion coordinates the ligands from the same tautomeric form with square-pyramidal geometry around each Cu atom. In the crystal structures, the copper(II) complex cation forms polymeric chains {[Cu(L)Cl]+}n with a bridging chlorine atom. One of the complexes was found to have a significantly higher cytotoxic potential in comparison with cisplatin in inhibition of several cell lines (HL60, REH, C6, L929 and B16). The results obtained on the basis of flow cytometry indicated that apoptosis could be possible mechanism of cell death.  相似文献   
106.
ABSTRACT: INTRODUCTION: A parachute mitral valve is defined as a unifocal attachment of mitral valve chordae tendineae independent of the number of papillary muscles. Data from the literature suggests that the valve can be distinguished on the basis of morphological features as either a parachute-like asymmetrical mitral valve or a true parachute mitral valve. A parachute-like asymmetrical mitral valve has two papillary muscles; one is elongated and located higher in the left ventricle. A true parachute mitral valve has a single papillary muscle that receives all chordae, as was present in our patient. Patients with parachute mitral valves during childhood have multilevel left-side heart obstructions, with poor outcomes without operative treatment. The finding of a parachute mitral valve in an adult patient is extremely rare, especially as an isolated lesion. In adults, the unifocal attachment of the chordae results in a slightly restricted valve opening and, more frequently, valvular regurgitation. CASE PRESENTATION: A 40-year-old Caucasian female patient was admitted to a primary care physician due to her recent symptoms of heart palpitation and chest discomfort on effort. Transthoracic echocardiography showed chordae tendineae which were elongated and formed an unusual net shape penetrating into left ventricle cavity. The parasternal short axis view of her left ventricle showed a single papillary muscle positioned on one side in the posteromedial commissure receiving all chordae. Her mitral valve orifice was slightly eccentric and the chordae were converting into a single papillary muscle. Mitral regurgitation was present and it was graded as moderate to severe. Her left atrium was enlarged. There were no signs of mitral stenosis or a subvalvular ring. She did not have a bicuspid aortic valve or coarctation of the ascending aorta. The dimensions and systolic function of her left ventricle were normal. Our patient had a normal body habitus, without signs of heart failure. Her functional status was graded as class I according to the New York Heart Association grading. CONCLUSIONS: A recently published review found that, in the last several decades, there have been only nine adult patients with parachute mitral valve disease reported, of which five had the same morphological characteristics as our patient. This case presentation should encourage doctors, especially those involved in echocardiography, to contribute their own experience, knowledge and research in parachute mitral valve disease to enrich statistical and epidemiologic databases and aid clinicians in getting acquainted with this rare disease.  相似文献   
107.
doi: 10.1111/j.1741‐2358.2011.00572.x Compressive strains and displacement in a partially dentate lower jaw rehabilitated with two different treatment modalities Background: Understanding of the biomechanical consequences of the stresses generated to the supporting bone during occlusal loading is significant for improving the design and clinical planning process in partial edentulism therapy. Objective: The aim of this study was to analyse the distribution of strain and displacement on the partially dentate lower jaw rehabilitated with an partial denture (RPD) and to compare it to the strain and displacement distribution on a partially dentate lower jaw rehabilitated with a cantilever fixed partial denture (FPD). Material and methods: The experimental models were a partially dentate mandible with full‐arch PFM crowns and RPD and a partially dentate mandible rehabilitated with a full‐arch cantilever FPD. Strains and displacement were measured using the Digital Image Correlation Method. Results: Displacement values of the first experimental model ranged from 0.31 to 0.54 mm with strains from 1.35 to 2.34%. Analysis of the second experimental model results showed displacement values from 0 to 0.34 mm, while strains were in the range of 0–1.40%. Conclusion: Higher displacements and strains of bone tissue were observed below the RPD, especially in the region of the distal abutment and distal portion of the free‐end saddle. Strains within bone and the bone‐denture contact area were mostly influenced by the teeth and denture vertical displacement.  相似文献   
108.
Lipid peroxidation product acrolein, well-known pollutant in tobacco and automotive smoke, accumulates in vivo bound to proteins. It suppresses p53 synthesis acting as potent carcinogenic factor for oral, respiratory and bladder carcinomas, while its possible association with colon carcinogenesis was not studied so far. We used genuine monoclonal antibody to evaluate immunohistochemical distribution of acrolein–protein adducts in 113 human colon tumours. The presence of acrolein–protein adducts was increasing with respect to colon carcinogenesis, from moderate appearance in tubular and villotubular low-grade adenomas to abundant and diffuse distribution in high-grade villotubular adenomas and Dukes A carcinomas. However, in advanced Dukes B and C carcinomas acrolein was hardly noticed, although, its protein adducts were found abundant in non-malignant colon epithelium of these patients. There was no relationship between p53 and acrolein distribution. According to these findings, acrolein seems to be lipid peroxidation product associated with transition from benign into malignant colon tumours.  相似文献   
109.
A survey of 50 km of the coast, including islands, rocks and offshore shallows, in the region of Rovinj (North Adriatic, Croatia) showed that the harvesting of the European date mussel Lithophaga lithophaga (L., 1758) is restricted to inclined, approximately vertical, surfaces. Usually, a stratum of rock, varying from several to about ten cm is removed by hammering, resulting in the complete eradication of sessile organisms. The damage was heavily widespread up to 6 m depth (47% of the total inclined surfaces for the whole area). Between 6 and 14 m depth, the damage was much less (14% from 6 to 10 and 7% from 10 to 14 m depth); below this depth, no damage was observed. The damage patterns coupled with the date mussel distribution, which was constrained by the nature of the substratum (limestone or dolomitic limestone), the general architecture of the rocky bottom and the depth. The structural complexity of inclined surfaces was quantified by 5 indices previously used in biota-substratum interaction studies. Heights of 11 pins placed 3 cm apart in a profile gauge were measured to determine the standard deviation of heights, the coefficient of variation of heights, the sum of squared heights, chain and tape ratio and circular variance of angles. Comparisons of these indices, among damaged and intact surfaces in different habitats and sites within habitats, showed a substantial decrease in complexity of the rocky substratum due date mussel harvesting. Thus, this human disturbance can permanently affect rocky shallow water communities as physical features of the substratum may exert strong effects on species.  相似文献   
110.
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