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In adult humans moral intervertebral disc (id) is an avascular tissue and becomes so called sequestrated autoantigen. Any acquired defect of anulus fibrosus may potentially lead to contact of immunocompetent cells circulating in the blood with id antigens thus inducing autoimmune reaction. 34 patients operated on because of lumbar discopathy were studied. The id injury was divided into: a) protrusion, B) simple prolapse, c) subligamentous prolapse, d) sequester. The samples of surgically removed id were subjected to histopathological and immunohistochemical study. Presence of granulation tissue, neovascularization and humoral response (confirmed by immunopositive reaction to factor VIII and IgG) was found in decreasing pattern in the following groups: I) sequesters, 2) simple prolapses, and 3) subligamentous prolapses. Among protrusions there were only two cases positive for IgG. A negative reaction to C3bR was seen in all the groups of id. The obtained results suggest that immune reaction against lumbar id is rather an effect than a cause of its herniation.  相似文献   
3.
One hundred and nine patients with primary myelodysplastic syndrome (MDS) were classified according to the French-American-British (FAB) criteria: 27 refractory anemia (RA, 25%), 26 RA with ringed sideroblasts (RARS, 24%), 16 RA with excess of blasts (RAEB, 15%), 10 RAEB in transformation (RAEB-t, 9%), 25 chronic myelomonocytic leukemia (CMMoL, 23%), and five unclassifiable MDS (4%). Forty-three were women and 66 were men (sex ratio 2:3). Age ranged from 30-92 years (mean 69 years) with nine patients aged less than 50 years (8%). A cytogenetic result was obtained in all cases. At initial study, a chromosome defect was observed in 56% of patients. Rates of abnormality depended on FAB subtype: 52% in RA, 100% in RA 5q-, 50% in RARS, 56% in RAEB, 70% in RAEB-t and 44% in CMMoL. The most frequent single defects were del(5q), -7/del(7q), del(20q), Y loss, and +8. Except for the 5q- syndrome entity, specific chromosome defects were not associated with particular FAB subtypes. Bone marrow (BM) insufficiency (22%) and leukemic transformation (21%) were the most important causes of death. The rate of leukemic transformation increased with the number of dysplastic BM cell lineages and was also associated with karyotype complexity and the proportion of abnormal/normal metaphases. The longest median survivals were observed in RARS (142 months) and RA/RA5q- (91 months) types. Median survivals decreased with increasing Bournemouth score values. Patients with three abnormal cell lineages had a median survival shorter than those with one or two abnormal lineages. Similarly, patients with complex defects had shorter survival than those with single or double defects or a normal karyotype. There was no statistically significant difference between survival of NN (normal), AN (abnormal/normal), and AA patients or between survival of patients with del(5q), -7/del(7q), +8 or del(20q).  相似文献   
4.
The interaction of a series of potent leishmanicidal aromatic diamidines resembling pentamidine, was studied with Leishmania infantum DNA and polynucleotides. The diamidines viz., CGP040215A, CGP033829A and CGP039937A, interacted with leishmania DNA as well as with the polynucleotides poly(dA)-poly(dT), poly(dA-dT) and poly(dG-dC). The thermodynamic analysis to determine the association constants and the binding enthalpy pointed toward binding of the diamidines at AT regions of the DNA. The results also indicate that the diamidines bind at the outside of the DNA double helix, probably to the minor groove regions, with hydrogen bonds connecting the amide nitrogen of the diamidine to carbonyl oxygen atoms of thymidine or adenosine bases. However, CGP040215A and CGP033829A, the bisaryl diamidines, showed higher affinity than CGP039937A, the monoaryl diamidine. The spectrophotometric analysis of the interaction of these diamidines to test their effects on the melting temperature of leishmanial DNA suggests non-intercalating binding. The diamidines also showed potent inhibition of DNA polymerase activity of L. infantum extracts in vitro.  相似文献   
5.

Mechanically milled FeCrNbB feedstock powders from commercial precursors were used to produce amorphous coatings through two different industrial thermal-spraying techniques: high-velocity oxygen fuel (HVOF) and flame spraying. Microstructure, thermal behavior, and hardness of the coatings and their corrosion resistances in acidic and alkaline chloride-rich media were comparatively studied. HVOF process was effective to produce ~ 200-µm-thick highly amorphous coatings with hardness over than 700 HV0.3 and low porosity (~ 5 pct). Flame-sprayed ~ 220-µm-thick coatings were nanocrystalline, composed of α-Fe, Fe2B, FeNbB, and Fe2O3 phases and presented hardness of 564 HV0.3 and ~ 10 pct porosity. Electrochemical measurements indicated that HVOF coatings exhibit higher corrosion resistance than flame-sprayed ones thanks to the higher amorphous content and lower porosity resulting from the former processing route. Electrochemical impedance spectroscopy results demonstrated that amorphous HVOF Fe60Cr8Nb8B24 (at. pct) coatings are interesting to protect mild steels such as the API 5L X80 against corrosion in chloride-rich environments.

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6.
Objective: To investigate sex differences in neurocognition and social functioning in schizophrenia and bipolar disorder and the possible role of sex as a moderator of this relationship. Method: Participants with schizophrenia (60 women/94 men), bipolar I disorder (55 women/51 men), and healthy controls (158 women/182 men) were assessed with an extensive neuropsychological test battery and a social functioning questionnaire. Results: We found significant main effects of sex for neuropsychological tests (p  相似文献   
7.
We employ Monte Carlo simulations in a specialized isothermal-isobaric and in the grand canonical ensemble to study structure formation in chiral liquid crystals as a function of molecular chirality. Our model potential consists of a simple Lennard-Jones potential, where the attractive contribution has been modified to represent the orientation dependence of the interaction between a pair of chiral liquid-crystal molecules. The liquid crystal is confined between a pair of planar and atomically smooth substrates onto which molecules are anchored in a hybrid fashion. Hybrid anchoring allows for the formation of helical structures in the direction perpendicular to the substrate plane without exposing the helix to spurious strains. At low chirality, we observe a cholesteric phase, which is transformed into a blue phase at higher chirality. More specifically, by studying the unit cell and the spatial arrangement of disclination lines, this blue phase can be established as blue phase II. If the distance between the confining substrates and molecular chirality are chosen properly, we see a third structure, which may be thought of as a hybrid, exhibiting mixed features of a cholesteric and a blue phase.  相似文献   
8.
We compared the Testpack Strep A plus (TPSAP) enzyme-linked immunosorbent assay test for group A beta-hemolytic streptococcal (GAS) antigen rapid detection with blood agar culture in 454 pediatric patients with clinical pharyngitis. Of the 454 patients, 118 (25.9%) had positive oropharyngeal cultures for GAS. TPSAP sensitivity was 89.9% (106 of 118) and specificity was 95.8% (322 of 336). We conclude that the TPSAP is specific enough to indicate treatment for a patient with a positive test but that a negative test should be confirmed by culture.  相似文献   
9.
In geography new measuring techniques and imaging modalities have led to a huge amount of distributed data requiring new digital processing techniques. Environmental monitoring programs and analysis of global change in geography, meteorology, and climatology require an interdisciplinary usage of knowledge about the ecological system earth. Until recently the traditional atlas has been the primary tool for collection and dissemination of geographical knowledge about the earth. To advance the concepts of the atlas it is necessary to work on a methodological base different from that discussed before under the slogan digital atlas. The new tools that are developed in this project will permit an interactive, individual, and problem-related representation, the combination, modeling, and the interchange of multi-dimensional spatial and temporal data sets. A number of theoretical and practical aspects will be addressed, e.g., the investigation and interpolation of the space-time-continuum, the interpretation of data using different scales, and the use of subject-specific models for representation of measured and simulated data. Within the scope of the project some goals are in the fields of the development of hierarchical methods for compression, visualization and data access, thus enabling efficient handling of distributed resources in worldwide data and computer networks. Another task of the project lies in the development of didactical concepts for digital use of scientific data and models by a wide class of users. The project is a joint venture of the Institute for Physical Geography at the University of Freiburg and the Institute of Computer Science at the University of Leipzig.  相似文献   
10.
The goal of long haul DWDM transmission is to deliver error-free digital information at extremely high data rates and over very long distances, ideally without the need for regeneration of the signal. Forward error correction (FEC) is a method of encoding a signal with additional overhead information so that optical receivers can detect and correct errors that occur in the transmission path. The latest enhancement for FEC is the use of a soft decision algorithm that significantly improves the optical reach. This study evaluates the impact of soft decision forward error correction (SD-FEC) technology upon network design and economics in a long haul optical transport network. The network study shows that the SD-FEC technology not only reduces the total cost of ownership, but also simplifies the network design. Real-world network models are utilized to quantify and compare results.  相似文献   
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