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991.
Weber C Michaelis M Vogel JU Cinatl J Kreuter J Langer K 《Journal of chromatography. B, Biomedical sciences and applications》1999,736(1-2):299-303
Diethylenetriaminepentaacetic acid (DTPA) is a commonly used chelating agent. Its antiviral, antibacterial and immunomodulatory effects are well documented. DTPA forms a highly stable complex with lead (II) with an increased absorption coefficient and a bathochromic shift of the absorption maximum compared to pure DTPA. Based on this complex a high-performance liquid chromatographic method for the quantitative detection of DTPA in biological fluids was developed. A calibration curve was prepared and linearity was shown in the concentration range between 10 mg l(-1) and 1000 mg l(-1) DTPA. The recovery in water and in human plasma showed the method to be suitable for routine use. 相似文献
992.
Knowledge discovery and knowledge validation in intensive care 总被引:1,自引:0,他引:1
Morik K Imhoff M Brockhausen P Joachims T Gather U Imboff M 《Artificial intelligence in medicine》2000,19(3):225-249
Operational protocols are a valuable means for quality control. However, developing operational protocols is a highly complex and costly task. We present an integrated approach involving both intelligent data analysis and knowledge acquisition from experts that support the development of operational protocols. The aim is to ensure high quality standards for the protocol through empirical validation during the development, as well as lower development cost through the use of machine learning and statistical techniques. We demonstrate our approach of integrating expert knowledge with data driven techniques based on our effort to develop an operational protocol for the hemodynamic system. 相似文献
993.
Srimanote P Ittiprasert W Sermsart B Chaisri U Mahannop P Sakolvaree Y Tapchaisri P Maleewong W Kurazono H Hayashi H Chaicumpa W 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》2000,18(1):37-45
Hybridomas secreting monoclonal antibodies (MAbs) to Trichinella spiralis were produced. Myeloma cells were fused with splenocytes of a mouse immunized with excretory-secretory (E-S) antigen of infective larvae. A large percentage of growing hybrids secreted antibodies cross-reactive to many of 23 heterologous parasites tested. Only 6 monoclones (designated 3F2, 5D1, 10F6, 11E4, 13D6 and 14D11) secreted MAbs specific to the E-S antigen and/or a crude extract (CE) of T. spiralis infective larvae. The 6 monoclones secreted IgM, IgG3, IgM, IgG3, IgG3 and IgG3, respectively. Clone 5D1 was selected to mass produce MAbs which were then coupled to CNBr-activated Sepharose CL-4B to prepare an affinity-purified antigen. Dot-blot ELISA with either purified antigen or CE was evaluated. There were 17 patients with acute trichinellosis and 76 individuals convalescing from T. spiralis infection (group 1). Controls were 170 patients with parasitic infections other than trichinellosis (group 2) and 35 healthy parasite-free controls (group 3). CE-ELISA was positive in all group 1 patients. However, sera from many group 2 patients also were reactive (opisthorchiasis-44.2%, schistosomiasis-44%, gnathostomiasis-30%, paragonimiasis-28.6%, taeniasis-27.3%, strongyloidiasis-23.1% and hookworm infections-20%). Affinity-purified antigen was 100% specific, all sera from group 2 and group 3 individuals tested negative. Although 74 of 76 patients (97.4%) with convalescing trichinellosis tested positive, sera from only 3 of 17 patients (17.6%) with acute T. spiralis were reactive. Thus, CE antigen is appropriate when sensitivity is needed, while purified antigen should be used when specificity is required. Dot-blot ELISA is easier to perform, more rapid and less expensive than indirect ELISA. Many samples can be assayed simultaneously, special equipment is not required, and results can be preserved for retrospective analysis. Dot-blot ELISA is therefore the method of choice for the rapid diagnosis of trichinellosis, particularly when more complex laboratory tests are unavailable. 相似文献
994.
Neutrophil migration from blood into inflamed tissues is mediated by adhesion molecules on neutrophils and on vascular endothelium. It was previously shown that the integrins VLA-4 and CD11/CD18 in combination mediate 70-80% of neutrophil recruitment to arthritic joints of rats. To investigate if the remaining recruitment involves the selectins, the effect of adhesion-blocking monoclonal antibodies (mAb) to each of the selectins (E-, P and L-), in combination with mAb to VLA-4 and CD18, on the migration of radiolabeled neutrophils to joints of rats with adjuvant arthritis was examined. Blocking P-selectin inhibited neutrophil accumulation in hindlimb joints by 40% whereas mAb to P- and E-selectin together inhibited the accumulation in all joints by 60% relative to anti-VLA-4 plus anti-CD18 treatment alone. Overall there was 90% inhibition relative to arthritic controls. Blocking E- or L-selectin alone or together had no effect. Our results demonstrate that P-selectin in particular and in concert with E-selectin are required for the VLA-4- and CD18-independent migration of neutrophils to sites of chronic arthritis in the rat. 相似文献
995.
Prof. H. Hofmann Dr. C. Bothge Dr. S. Haselwarter Prof. L. Heinemann Dr. W. Barth Dr. E. Schüler Prof. U. Laaser Dr. M. Siegel Prof. F. C. Luft Die Intersalt-Forschungsgruppe aus BRD und DDR 《Journal of molecular medicine (Berlin, Germany)》1990,68(13):655-663
Summary The relationships between body mass index (BMI) and age, alcohol consumption, 24-hr urinary electrolyte excretion, and BP were studied in 588 subjects from three German centers participating inIntersalt, a highly standardized, previously reported protocol. Men and women aged 20–59 were sampled in Bernried, FRG; Cottbus, GDR; and Heidelberg, FRG. The subjects from the three centers did not differ in BMI, level of education, physical activity, cigarette- or alcohol-consumption patterns, or urinary Cl excretion. Mean Na excretion was 167, 147, and 172 mmol/24 hr in Bernried, Cottbus, and Heidelberg, while mean K excretion was 72, 55, and 73 mmol/24 hr, respectively. The excretion of these electrolytes was significantly lower in Cottbus than in Bernried or Heidelberg. BMI increased progressively in men with age; in women BMI plateaued until the 5th decade, after which it increased to equal that of men. In individual centers, the excretion of electrolytes was correlated with BML Sodium and chloride excretion were highly correlated. The data from each individual center were fitted to a multiple regression model. Age, BMI, sex, and alcohol consumption entered the model. 相似文献
996.
N. Freudenberg P. Rahner C. Darda U. N. Riede M. Schubert K. Frenzer-Welle A. Kiss G. Veres T. Nees R. Lamers C. Kortsik 《Virchows Archiv : an international journal of pathology》1996,428(3):187-194
We investigated the reaction of the cellular immune system of liver and blood in the C57BL/6 mouse to a metastasizing Lewis lung carcinoma. The cellular immune system of the liver consists of mature and immature macrophages, B-cells, T-cells including their subpopulations, and natural killer cells, and their percentage frequencies differ significantly from those in the corresponding mononuclear blood cell (MBC) compartment. This suggests that the hepatic immune cells represent a system with autonomous function showing a typical homing of its members. Imminent metastasis to the liver is signalled by impressive alterations in the percentage frequencies of nonparenchymal liver cells (NPLC). There are a dramatic loss of mature macrophages, an increase in immature macrophages, a reduction of T-helper cells leading to a low CD4/CD8 ratio, and an increase in natural killer cells. In the blood, the corresponding precursor cells show comparable changes with a delay of at least 2 days. Early metastasis is accompanied by a significant increase in mononuclear NPLC producing tumour necrosis factor . The alterations in percentage frequencies of the NPLC during tumour metastasis differ markedly from the changes in these cells in the liver during endotoxinaemia. 相似文献
997.
Force generation and tissue glucose metabolism were measured in the urinary bladder smooth muscle from rats with streptozotocin-induced diabetes (7–8 wk duration). Bladder wet wt was almost 4–fold higher in the diabetic animals compared with the untreated controls. Morphological analysis showed that the growth was associated with hypertrophy of the smooth muscle component in the bladder wall. Force generation of isolated bladder strip preparations was measured in vitro at different ambient oxygen tensions. Activation of intramural nerves, with electrical field stimulation, induced contractions that were unaffected by reduction of oxygen tension down to Po2 100 mmHg for both control and diabetic muscle strips. At zero Po2 force was reduced by approximately 10–20% in both groups. High-K+ solution induced ‘tonic’ contractions that were slightly more inhibited by lowering Po2. At intermediate Po2 (between 100 and 20 mmHg) the diabetic muscle gave slightly higher force. At zero Po2 no significant difference could be detected between strips from control and diabetic animals. Oxygen consumption and lactate production in the preparations were determined at a Po2 of 290 mmHg and related to the volume of smooth muscle. At zero Po2 lactate formation increased 3- to 4-fold. The metabolic tension cost was lower at zero Po2 No differences in basal and contraction related metabolic rates could be detected between the two groups under normoxic and anoxic conditions. The maximal activity of lactate dehydrogenase (LDH) determined in tissue sampIes was about 2-fold higher in the diabetic bladder muscle. This increased enzymatic activity could thus not be correlated with any altered metabolic properties of the smooth muscle in the urinary bladder from diabetic rats. 相似文献
998.
Immunohistochemical characterization of an anti-epithelial monoclonal antibody (mAB lu-5) 总被引:7,自引:0,他引:7
J. von Overbeck C. Stähli F. Gudat H. Carmann C. Lautenschlager U. Dürmüller B. Takacs V. Miggiano Th. Staehelin Ph. U. Heitz 《Virchows Archiv : an international journal of pathology》1985,407(1):1-12
Summary A mouse monoclonal antibody (mAB lu-5) was prepared using a lung cancer cell line as an antigen. The selected clone produces an IgG with a gamma-1 heavy chain and a kappa-light-chain. Immunohistochemical testing of mAB lu-5 on 117 normal tissue biopsies and 474 tumours revealed reactivity with an intracytoplasmic, formaldehyderesistant antigen present in most epithelial and mesothelial cells, but absent in mesenchymal cells. The antibody can therefore be used as a first order, pan-epithelial marker. It proved also useful for fast tumour diagnosis on frozen sections. 相似文献
999.
A novel factor was found in the medium conditioned by SV40-transformed human embryo fibroblasts, which stimulate concanavalin A-induced thymocyte DNA synthetic response. This activity was estimated to be 10-15 kD and divided into two activities by ion exchange chromatography. One of them is a protein molecule and the other is a glycoprotein. In addition, these activities are not derived from the growth factors reported previously such as interleukin 2 (Morgan, R., Ruscetti, F. and Gallo, R. C. (1976) Science 193, 1007-1008) and transforming growth factor (De Larco, J. E. and Todaro, G. J. (1978) Proc. Natl. Acad. Sci. U.S.A. 75, 4001-4005). 相似文献
1000.
The effect of temporary position changes, sitting up from supine, on extracellular (ECW) and intracellular (ICW) resistances and fluid volumes calculated from whole body bioimpedance using a Xitron 4200 impedancemeter was investigated on 8 patients during dialysis for a total of 11 tests. It was found that ECW resistance decreased instantaneously by an average of 2.3% when the patient sits up, due to plasma and interstitial fluid shift into the legs which decreases leg resistance, the major contributor to total resistance. This drop in resistance is incorrectly interpreted by the device as an increase in ECW volume which averages 235 ml. But this effect is completely reversible and both ECW resistance and fluid volume rapidly resume their normal course when the patient returns to his initial position. No significant variation in ICW resistance was observed in any of the patients at the position change. We conclude that segmental impedance, which has been proposed to minimize this artifact, is not advisable in dialysis monitoring and that it is simpler to ignore or switch off measurements during the position change so that later data are not affected by it. 相似文献