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1.
Results of treatment obtained in 273 patients with HD from 1971 to 1980 were compared with 240 patients with HD in the period from 1951 to 1970. All patients in our material were analysed by taking into consideration the histological type and the clinical stage. We confirmed the prolongation of the survival time in the patients with HD in last ten years to 18 months. The introduction of polychemotherapy contributed to this observation.  相似文献   
2.
A series of experimental investigations are described concerning the influence of hypokinesia, acceleration and associated effect of hypokinesia and acceleration in different periods of time on the displacement of plasma proteins and on bioelectric activity of striated muscles. Disturbances in hemodynamic and bioelectric activity of striated muscles by these two factors are discussed.  相似文献   
3.
Adenosine and adenosine derivatives are the main regulators of purinoceptors (P1 and P2) mediated hemostasis and blood pressure. Since impaired hemostasis and high blood pressure lead to atherosclerosis and to the development of aneurysm, in this study we tested and compared the concentration of extracellular purines (e-purines) in the blood in of patients having abdominal aortic aneurysm with that from healthy volunteers. Whereas adenine nucleosides and nucleotides level in human blood plasma was analysed using reverse phase high performance liquid chromatography (HPLC), cholesterol concentration was estimated by an enzymatic assay. We did not find any correlation between e-purines concentration and the age of healthy volunteers. Furthermore, the sum level of e-purines (ATP, ADP, AMP, adenosine, and inosine) in the control group did not exceed 70 μM, while it was nearly two-fold higher in the blood of patients having abdominal aortic aneurysm, (123 μM). In a special case of people with Leriche Syndrome, a disease characterized by deep atherosclerotic changes, the e-purines level had further increased. Additionally, we also report typical atherosclerotic changes in the aorta using histological assays as well as total cholesterol rise. The significant rise in cholesterol concentration in the blood of the patients with abdominal aortas aneurysm, compared with the control groups, was not unique since 23% of the healthy people also exceeded the normal level of cholesterol. Therefore, our results strongly indicate that the estimation of e-purines concentration in the blood may serve as another indicator of atherosclerosis and warrant further consideration as a futuristic diagnostic tool.  相似文献   
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Abundance and composition of nematode fauna were examined in the benthic microbial mats and upper sediment layer of the littoral of acidified (pH 4.6 to 5.7) lakes. Nematodes constituted from 58% to 90% of all the invertebrates present (excluding protozoans and rotifers). In the examined material, the majority of nematodes was represented by 3 taxa of which Ironus was found specifically associated with the mats. It was concluded that the persistence of benthic mats may be linked to the metabolic activity of the associated nematode fauna.  相似文献   
6.
T cells play a major role in allograft rejection, which occurs after T cell activation by the engagement of several functional molecules to form an immune synapse with alloantigen presenting cells. In this study, the immune synapse was targeted using mAbs directed to the TCR beta-chain (TCRβ) and lymphocyte function-associated antigen−1 (LFA1) to induce long-term allograft survival. Evaluation of antigen-specific T cell responses was performed by adoptively transferring CFSE labeled transgenic OT-II cells into wild-type mice and providing OVA peptide by intravenous injection. Graft survival studies were performed in mice by transplanting BALB/c ear skins onto the flanks of C57BL/6 recipients. The anti-TCRβ plus anti-LFA1 mAb combination (but not either mAb alone) abrogated antigen-specific T cell responses invitro and invivo. Transient combination therapy with these agents resulted in significantly prolonged skin allograft survival in mice (51±10 days; p<0.01) when compared to treatment with either anti-TCRβ mAb (24±5 days) or anti-LFA1 mAb (19±3 days) alone or no treatment (10±1 days). When lymphoid tissues from these mice were analyzed at different times post-transplant, only those receiving the combination of anti-TCRβ and anti-LFA1 mAbs demonstrated long-lasting reductions in total T cell numbers, cellular and humoral anti-donor responses, and expression of CD3 on the surface of T cells. These results demonstrate that transient anti-TCRβ and anti-LFA1 mAb combination therapy abrogates antigen-reactive T cell responses with long-lasting effects that significantly prolong allograft survival.  相似文献   
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In this study, the seedlings of two wheat cultivars were used: drought-resistant Chinese Spring (CS) and drought-susceptible (SQ1). Seedlings were subjected to osmotic stress in order to assess the differences in response to drought stress between resistant and susceptible genotype. The aim of the experiment was to evaluate the changes in physiological and biochemical characteristics and to establish the optimum osmotic stress level in which differences in drought resistance between the genotypes could be revealed. Plants were subjected to osmotic stress by supplementing the root medium with three concentrations of PEG 6000. Seedlings were grown for 21 days in control conditions and then the plants were subjected to osmotic stress for 7 days by supplementing the root medium with three concentrations of PEG 6000 (D1, D2, D3) applied in two steps: during the first 3 days of treatment ?0.50, ?0.75 and ?1.00 and next ?0.75, ?1.25 and ?1.5 MPa, respectively. Measurements of gas exchange parameters, chlorophyll content, height of seedlings, length of root, leaf and root water content, leaf osmotic potential, lipid peroxidation, and contents of soluble carbohydrates and proline were taken. The results highlighted statistically significant differences in most traits for treatment D2 and emphasized that these conditions were optimum for expressing differences in the responses to osmotic stress between SQ1 and CS wheat genotypes. The level of osmotic stress defined in this study as most suitable for differentiating drought resistance of wheat genotypes will be used in further research for genetic characterization of this trait in wheat through QTL analysis of mapping population of doubled haploid lines derived from CS and SQ1.  相似文献   
9.
We evaluated a neural network model for prediction of glucose in critically ill trauma and post-operative cardiothoracic surgical patients. A prospective, feasibility trial evaluating a continuous glucose-monitoring device was performed. After institutional review board approval, clinical data from all consenting surgical intensive care unit patients were converted to an electronic format using novel software. This data was utilized to develop and train a neural network model for real-time prediction of serum glucose concentration implementing a prediction horizon of 75 minutes. Glycemic data from 19 patients were used to “train” the neural network model. Subsequent real-time simulated testing was performed in 5 patients to whom the neural network model was naive. Performance of the model was evaluated by calculating the mean absolute difference percent (MAD%), Clarke Error Grid Analysis, and calculation of the percent of hypoglycemic (≤70 mg/dL), normoglycemic (>70 and <150 mg/dL), and hyperglycemic (≥150 mg/dL) values accurately predicted by the model; 9,405 data points were analyzed. The models successfully predicted trends in glucose in the 5 test patients. Clark Error Grid Analysis indicated that 100.0% of predictions were clinically acceptable with 87.3% and 12.7% of predicted values falling within regions A and B of the error grid respectively. Overall model error (MAD%) was 9.0% with respect to actual continuous glucose modeling data. Our model successfully predicted 96.7% and 53.6% of the normo- and hyperglycemic values respectively. No hypoglycemic events occurred in these patients. Use of neural network models for real-time prediction of glucose in the surgical intensive care unit setting offers healthcare providers potentially useful information which could facilitate optimization of glycemic control, patient safety, and improved care. Similar models can be implemented across a wider scale of biomedical variables to offer real-time optimization, training, and adaptation that increase predictive accuracy and performance of therapies.  相似文献   
10.
The failure of current strategies to provide an explanation for controversial findings on the pattern of pathophysiological changes in Alzheimer''s Disease (AD) motivates the necessity to develop new integrative approaches based on multi-modal neuroimaging data that captures various aspects of disease pathology. Previous studies using [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) and structural magnetic resonance imaging (sMRI) report controversial results about time-line, spatial extent and magnitude of glucose hypometabolism and atrophy in AD that depend on clinical and demographic characteristics of the studied populations. Here, we provide and validate at a group level a generative anatomical model of glucose hypo-metabolism and atrophy progression in AD based on FDG-PET and sMRI data of 80 patients and 79 healthy controls to describe expected age and symptom severity related changes in AD relative to a baseline provided by healthy aging. We demonstrate a high level of anatomical accuracy for both modalities yielding strongly age- and symptom-severity- dependant glucose hypometabolism in temporal, parietal and precuneal regions and a more extensive network of atrophy in hippocampal, temporal, parietal, occipital and posterior caudate regions. The model suggests greater and more consistent changes in FDG-PET compared to sMRI at earlier and the inversion of this pattern at more advanced AD stages. Our model describes, integrates and predicts characteristic patterns of AD related pathology, uncontaminated by normal age effects, derived from multi-modal data. It further provides an integrative explanation for findings suggesting a dissociation between early- and late-onset AD. The generative model offers a basis for further development of individualized biomarkers allowing accurate early diagnosis and treatment evaluation.  相似文献   
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