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151.
Summary The hemagglutination of human and rat red blood cells by adeno-virus type 27 is completely inhibited by treatment of the virus with p-chlormercuribenzoic acid (PCMB), N-ethylmaleimid (NEM) and KJO4. Treatment of the erythrocytes has no effect. The action of PCMB and NEM is fully reverted by reduced glutathione or 1-cysteine. Under the same conditions, the hemagglutinins of other adenovirus types belonging also toRosen's group II are unaffected by these reagents.

Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
152.
Summary The present report describes the results of a combined morphological, enzyme- and immunohistochemical analysis of nine cases of malignant non Hodgkin's lymphomas (NHL) clinically presenting as lethal midline granuloma. In a previous report written before antibodies directed against B and T lymphocytes were available, a histiocytic origin of such neoplasms had been suggested. A panel of antibodies reactive with most B cells (L26, MB1, KiB3) and a majority of T cells (MT1, UCHL1) was applied on paraffin sections of formalin fixed tissues as well as antibodies directed against leukocyte common antigen (LCA), myeloid/histiocyte antigen (MAC 387), lysozyme, alpha-1-antitrypsin, alpha-1-antichymotrypsin, S-100 protein, prekeratin and immunoglobulin light chains. Enzyme histochemistry included tests for non-specific acid esterase, acid phosphatase, betaglucuronidase and chloroacetate esterase. As a result, five T, two B and two unclassified (malignant histiocytosis probable) NHL were identified, indicating distinct heterogeneity of NHL as causative disorders in lethal midline granuloma.  相似文献   
153.
Leukotriene and prostaglandin production by mouse peritoneal macrophages was investigated. It could be shown that the tumour promoter 12-O-tetradecanoylphorbol-13-acetate initiated the release of prostaglandin E2 but had little effect on the release of leukotriene C4-like immunoreactivity. The divalent cation ionophore A 23187 at concentrations between 10–6 and 10–8 mol/l initiated prostaglandin as well as leukotriene release. This prostaglandin and leukotriene release could be modulated by drugs. Non-steroidal anti-inflammatory drugs including benoxaprofen inhibited prostaglandin release but simultaneously enhanced leukotriene production. The analgesics paracetamol and 4-methylaminoantipyrine had similar effects at high concentrations. The experimental compound BW 755 c inhibited prostaglandin and leukotriene production while the antithrombotic compound nafazatrom inhibited the production of leukotriene C4-like immunoreactivity but enhanced prostaglandin E2 production. Nordihydroguaiaretic acid inhibited prostaglandin and leukotriene production. The results show that the metabolism of arachidonic acid in macrophages via the cyclooxygenase or the lipoxygenase pathway is dependent on the stimulus applied. Both pathways can be inhibited conjointly or selectively by drugs. Our results do not provide evidence that differences in anti-inflammatory activity claimed for some of the drugs tested can be explained by differential inhibition of either pathway. The experimental system described may be used for assessing the potency of drugs to inhibit the lipoxygenase and the cyclooxygenase pathway of arachidonic acid metabolism.  相似文献   
154.
A sandwich ELISA system has been developed for the detection of C1q in human serum. It is specific, uses monoclonal antibodies, is sensitive into the nanogram range and is rapidly performed. Therefore, it may be a helpful tool for clinical routine diagnosis, e.g., detecting abnormal C1q levels in patients with rheumatic disorders. Various combinations of poly- and monoclonal antibodies were tested in a sandwich assay. One of these combinations, in particular, resulted in a highly reproducible standard curve: C1q bound to solid-phase polyclonal anti-C1q was detected by the monoclonal antibody 242 G3. In this assay, the C1q concentration in sera of normal individuals was found to be 160 micrograms/ml (mean value of 70 normal human sera). This ELISA detected nanogram levels of C1q and gave results comparable to those obtained by haemolytic C1q titration. One nanogram of C1q corresponded to ca. 2.6 X 10(10) effective C1q molecules. With this technique, selective C1q deficient sera as well as sera from patients with rheumatoid diseases were analysed.  相似文献   
155.
The polyene formation during degradation of a commercial suspension-polymerized poly(vinyl chloride) (PVC) in the solid state is discussed with respect to the PVC texture. Above the glass transition temperature (Tg), the polyene length distribution is characterized by a high amount of very short polyenes (conjugation length i < 6) due to the dehydrochlorination in the amorphous phase, and a second population of longer polyenes (i about 14) due to dehydrochlorination in micellar (B-type) crystals. According to the melting range of these crystals (120–180°C), the formation of longer polyenes reaches a maximum at 120°C. A third population of polyenes could be observed investigating the thermal and photolytical degradation of PVC below Tg. The absorption spectra of the degraded samples show a maximum centred at 550 nm (i = 21) due to the dehydrochlorination in the highly ordered lamellar (A-type) crystals. This result verifies the existence of highly syndiotactic sequences in commercial PVC formed during the first stage of polymerization, as demonstrated recently. The preferential dehydrochlorination in these crystals during the initial stage of degradation of PVC below Tg should be considered when discussing the long term stability of PVC products.  相似文献   
156.
The content of dissolved oxygen was determined by four independent methods in a series of non-aqueous or heterogenous systems. The Lex-O2-Content Analyzer represents a fast and simple apparatus that employs a coulometric oxygen assay with Hersch cell detection. A comparison of the results with different methods demonstrates the reliability of the Lex-O2 in the determination of oxygen dissolved in heterogeneous or non-aqueous systems. Therefore, this apparatus can be recommended for the measurement of oxygen in oxygenator or perfusion fluids, as well as in blood substitutes or other oxygen transporting systems.  相似文献   
157.
The new HIDA derivative, 99mTc-dimethyl-iodine-HIDA (JODIDA), was compared with 99mTc-diisopropyl-HIDA (DISIDA) in 17 patients with jaundice by means of paired cholescintigraphic imaging studies. The following parameters were visually assessed: the extent of urinary tract visualization, biliary contrast and appearance time, and gallbladder visualization and appearance time. In the 6 patients with a total bilirubin level of between 19 and 66 mol/l (1.1 and 3.9 mg/dl), both radiopharmaceuticals gave similar results except for the moderate visualization of the urinary tract with DISIDA in contrast to JODIDA. In the remaining 11 patients with a total bilirubin level between 102 and 1303 mol/l (6 and 76 mg/dl), JODIDA showed significant advantages over DISIDA: non-visualization of the urinary tract, stronger and faster biliary contrast, and better gallbladder visualization. JODIDA thus offered substantial diagnostic advantages over DISIDA in 8 of these patients. In 4 patients, the differential diagnosis of jaundice (intrahepatic or mechanical disorder) was possible with JODIDA, whereas DISIDA either could not visualize intestinal or gallbladder activity at all or could not differentiate it from the urinary tract. In one patients, JODIDA offered faster (18 h) diagnosis. In the remaining 3 patients, other, substantially false interpretations could be avoided through the use of JODIDA. Further clinical experience with JODIDA in more than 40 patients confirmed the results of this study. We concluded that JODIDA is of significant advantage over DISIDA in clinical situations such as total bilirubin level above 80–100 mol/l (4.7 to 5.8 mg/dl), examination of small children and critically ill patients and suggestion of bile leakage. As there are also no clinical disadvantages, it could become the rediopharmaceutical of choice for hepatobiliary imaging.  相似文献   
158.
European Journal of Epidemiology - Background: Meta-analyses of randomized controlled trials have shown that vitamin D supplementation reduces cancer mortality by 13%. Vitamin D fortification of...  相似文献   
159.
BackgroundInjury to kidney podocytes often results in chronic glomerular disease and consecutive nephron malfunction. For most glomerular diseases, targeted therapies are lacking. Thus, it is important to identify novel signaling pathways contributing to glomerular disease. Neurotrophic tyrosine kinase receptor 3 (TrkC) is expressed in podocytes and the protein transmits signals to the podocyte actin cytoskeleton.MethodsNephron-specific TrkC knockout (TrkC-KO) and nephron-specific TrkC-overexpressing (TrkC-OE) mice were generated to dissect the role of TrkC in nephron development and maintenance.ResultsBoth TrkC-KO and TrkC-OE mice exhibited enlarged glomeruli, mesangial proliferation, basement membrane thickening, albuminuria, podocyte loss, and aspects of FSGS during aging. Igf1 receptor (Igf1R)–associated gene expression was dysregulated in TrkC-KO mouse glomeruli. Phosphoproteins associated with insulin, erb-b2 receptor tyrosine kinase (Erbb), and Toll-like receptor signaling were enriched in lysates of podocytes treated with the TrkC ligand neurotrophin-3 (Nt-3). Activation of TrkC by Nt-3 resulted in phosphorylation of the Igf1R on activating tyrosine residues in podocytes. Igf1R phosphorylation was increased in TrkC-OE mouse kidneys while it was decreased in TrkC-KO kidneys. Furthermore, TrkC expression was elevated in glomerular tissue of patients with diabetic kidney disease compared with control glomerular tissue.ConclusionsOur results show that TrkC is essential for maintaining glomerular integrity. Furthermore, TrkC modulates Igf-related signaling in podocytes.  相似文献   
160.
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