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91.
Summary Lysis of mitochondria from sea urchin embryos with Triton X-100 led to a complete conversion of DNA-containing mitochondrial residues into protein-DNA complex with a density higher than 1.22 g/cm3 in sucrose solutions. This complex banded isopycnically in metrizamide gradients at a density of 1..26 g/cm3. Exposure to mixtures of Triton X-100 with Tween 80 resulted in progressively less delipitated and disorganized mitochondria over Tween/Triton weight ratios from 1 to 2, with the retention of the starting buoyant density in sucrose of approximately 1.16 g/cm3 at Tween/Triton ratios above 2.5. The DNA-internal protein complex sedimented with the bulk of the surviving mitochondrial structure under all conditions studied. No free DNA could be detected under any conditions of membrane removal.  相似文献   
92.
Summary The developmental changes in the pattern of chromatin nonhistone proteins have been investigated. The main feature of the observed changes was not the introduction of new or the disappearence of earlier existing species, but the stage-specific alterations in the rate of biosynthesis of the nonhistone protein constituents.  相似文献   
93.
94.

Background  

As a continuation of the previous findings in human fetuses, accidental finding of an accessory vascular component in the posterior part of CAC of human adult cadavers inspired the authors to present and compare its posterior part configuration.  相似文献   
95.
PCR-based clonality testing can be performed in all lymphoproliferations by analysing gene rearrangements of antigen receptors, rearrangements that are unique for each kind of lymphocyte. Reactive lymphoproliferations have polyclonally rearranged Ig/TCR genes, whereas malignant proliferations (leukaemias and lymphomas) show clonal rearrangements. The aim of this study was to assess the clinical benefits of clonality testing with previously evaluated consensus primers in leukaemia patients. The study included peripheral blood and bone marrow samples of 67 leukaemia patients (32 B-CLL, 24 B-ALL and 11 T-ALL). Clonality testing was based on PCR amplification of rearranged IgH and TCR genes. During diagnosis, monoclonal pattern was found in all analysed B-CLL and T-ALL samples. Testing in B-ALL patients showed positive results in all bone marrow and one peripheral blood samples. Results of clonality testing in B-CLL patients during follow-up were concordant between peripheral blood and bone marrow. Obtained results corresponded to clinical course in all but one patient. In B-ALL group, results of molecular testing in peripheral blood and bone marrow confirmed remission estimated according to clinical criteria in all except one patient. Before any clinical sign of relapse, monoclonal pattern was found in six/seven patients by bone marrow and in three/seven patients by peripheral blood analysis, respectively. Results of molecular monitoring in T-ALL patients did not confirme clinical evaluation in two patients. Obtained results indicate high accuracy of re-evaluated primers for clonality assessment in ALL and CLL patients at the time of diagnosis. Results of clonality testing in B-ALL patients indicate that bone marrow analysis has higher sensitivity compared to analysis of peripheral blood.  相似文献   
96.
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   
97.
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   
98.

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   
99.
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   
100.
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   
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