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31.
Incidence of deep vein thrombosis in bedridden non-surgical patients   总被引:4,自引:0,他引:4  
In order to detect deep vein thrombosis (DVT), 101 patients with acute medical or infectious disorders were examined with the 125I-fibrinogen uptake test. All patients were bedridden on admission and were scanned daily from the second to the eighth day. Thirteen patients developed a positive fibrinogen uptake test. Thus, if a positive test is interpreted as DVT, the incidence of DVT was 13% in our bedridden patients. Of the patients admitted because of heart disease or pneumonia 20% had DVT, but only 4% of those admitted with other diagnoses. Other clinical "risk factors" studied, could not identify patients who developed DVT.  相似文献   
32.
The newly described immunoglobulin G-binding streptococcal surface protein, protein G, was used to prepare and characterize rabbit antibodies. The antibodies were directed against rat hormone-sensitive lipase, the rate-limiting enzyme in the hydrolysis of the triacylglycerols stored in adipose tissue. Antiserum was obtained after two injections with 20 micrograms enzyme protein, and the immunoglobulin fraction was obtained using a protein G-based solid-phase radioimmunoassay. The hydrolysis of acylglycerols by the enzyme was inhibited by the antibodies, and the enzyme could be efficiently removed from a solution using the antibodies and heat-killed streptococci expressing surface protein G. By Western blot and detection with 125I-protein G, the antibodies were found to selectively bind to hormone-sensitive lipase and to a smaller extent to two minor contaminants, possibly proteolytic fragments of the lipase. The amount of 125I-labelled protein G bound to the lipase on the blot was quantitatively related to the amount of enzyme protein down to the detection limit 10 ng.  相似文献   
33.
Human monocytes were prepared from peripheral blood by buoyant density centrifugation and subsequent absorption-elution on a column of gelatin beads. The eluted fraction containing 60-80% monocytes was used as feeder layer in cloning of the human lymphoma line RH-L4, the human myeloma line SKO-007, and a human hybridoma cell derived from the latter line. Cloning efficiencies were high in both liquid and semisolid media with all 3 cell lines tested. Feeder monocytes could also be successfully used after having been stored in liquid nitrogen.  相似文献   
34.
The antiarrhythmic effects of tocainide, administered as a bolus injection of 750 mg followed by oral therapy, and conventional lidocaine therapy were evaluated in 40 patients admitted for suspected acute myocardial infarction (AMI) and showing high-grade premature ventricular complexes (PVCs). The mean hourly PVC rate before therapy was 928 and its reduction was equally significant in the tocainide group, 73%, and in the lidocaine group, 68%. The number of 5-minute periods with multiform, paired and R/T PVCs or ventricular tachycardia was also significantly reduced, by 78% in the tocainide group and by 71% in the lidocaine group. Ten patients in the tocainide group reported moderate side-effects, compared to 13 in the lidocaine group, where the infusion had to be discontinued in 5 patients and the rate had to be reduced in 4. Tocainide, an amine analogue of lidocaine, is considered just as effective as lidocaine in patients with high-grade PVCs and suspected AMI.  相似文献   
35.
Myelin antigen reactive T cells in cerebrovascular diseases.   总被引:6,自引:0,他引:6       下载免费PDF全文
T cell reactivities to the putative autoantigens myelin basic protein (MBP), MBP peptides with amino acid residues 110-128 and 148-165, and myelin proteolipid protein (PLP) were examined in patients with acute ischaemic cerebrovascular disease (CVD) and, for comparison, in patients with inflammatory neurological diseases and other neurological diseases. A quantitative measure of these T cell reactivities was obtained by assessing numbers of T cells among blood and cerebrospinal fluid (CSF) mononuclear cells that secreted IFN-gamma in response to antigen in vitro. Higher numbers of T cells reactive with each of these four antigens were detected in peripheral blood from patients with CVD compared with patients of the two control groups. Among blood cells from the CVD patients, their average number was 2.3-4.2/10(5) mononuclear cells. MBP reactive T cells were several-fold enriched in the CSF of CVD patients. The findings strongly suggest that brain damage in context with acute CVD leads to an in vivo expansion of myelin reactive T cells.  相似文献   
36.
Thirst in response to intracarotid and intravenous infusions (1.5 ml/min) of various hypertonic, equi-osmolal solutions was studied in the goat. Intracarotid infusions of 1 M NaCl and of 2 M fructose induced conspicuous cumulative drinking. The amount of water drunk during intracarotid infusions of 2 M urea and glycerol was only about a third of that consumed during the corresponding infusions of NaCl and fructose. During intracarotid infusions of 2 M galactose and glucose drinking was inconsistent. Of the intravenous infusions only hypertonic NaCl had a consistent dipsogenic effect. However, the amount of water consumed was considerably smaller and the latency time for drinking much longer than during the intracarotid infusions of NaCI. It is concluded that intracarotid infusions of hypertonic solutions act as considerably stronger thirst stimuli than corresponding intravenous infusions, and that the most pronounced dipsogenic effect is obtained by intracarotid infusions of those hypertonic solutions which also most effectively release antidiuretic hormone in the hydrated goat. The possibility is discussed that intracarotid infusions may stimulate the thirst mechanism indirectly via a rise in the Na+ concentration of the cerebrospinal fluid.  相似文献   
37.
Luminex technology allows simultaneous detection of several analytes in a single well. Applications have been recently developed for the detection of autoantibodies. PURPOSE: To evaluate the performances and convenience of the Fidis analytical system (BioMedical Diagnostics, Marnes-la-Vallee, France) for the detection of nine autoantibodies associated with connective diseases: SS-A, SS-B, Sm, RNP, Scl-70, Jo-1, CENP-B, P ribosomal and double stranded DNA antibodies. MATERIALS AND METHODS: Three hospital laboratories analysed 366 samples taken from their serum banks and corresponding to the main systemic autoimmune diseases. Control samples included 120 sera from blood donors and 42 sera from patients with dysglobulinemia. RESULTS: In each laboratory, handling of this new analytical system was easy. Results are readily obtained: nine autoantibodies are quantitated in fourty-four sera in less than two hours. A clear-cut discrimination between negative and positive results was observed, due to very low backgrounds. Intra-assay and inter-assay variations were low: coefficients of variation were under 10% in 80 and 64% of the cases, respectively. Results obtained with Fidis correlated satisfactorily with those obtained with the numerous routine techniques used in each laboratory. The overall concordance exceeded 93%. CONCLUSION: Fidis is a reliable and time-saving analytical system for the detection of autoantibodies associated with systemic autoimmune diseases.  相似文献   
38.
39.
Magnetic response image plane nonuniformity and stochastic noise are properties that greatly influence the outcome of quantitative magnetic resonance imaging (MRI) evaluations such as gel dosimetry measurements using MRI. To study these properties, robust and accurate image analysis methods are required. New nonuniformity level assessment methods were designed, since previous methods were found to be insufficiently robust and accurate. The new and previously reported nonuniformity level assessment methods were analyzed with respect to, for example, insensitivity to stochastic noise; and previously reported stochastic noise level assessment methods with respect to insensitivity to nonuniformity. Using the same image data, different methods were found to assess significantly different levels of nonuniformity. Nonuniformity levels obtained using methods that count pixels in an intensity interval, and obtained using methods that use only intensity values, were found not to be comparable. The latter were found preferable, since they assess the quantity intrinsically sought. A new method which calculates a deviation image, with every pixel representing the deviation from a reference intensity, was least sensitive to stochastic noise. Furthermore, unlike any other analyzed method, it includes all intensity variations across the phantom area and allows for studies of nonuniformity shapes. This new method was designed for accurate studies of nonuniformities in gel dosimetry measurements, but could also be used with benefit in quality assurance and acceptance testing of MRI, scintillation camera, and computer tomography systems. The stochastic noise level was found to be greatly method dependent. Two methods were found to be insensitive to nonuniformity and also simple to use in practice. One method assesses the stochastic noise level as the average of the levels at five different positions within the phantom area, and the other assesses the stochastic noise in a region outside the phantom area.  相似文献   
40.
By two-colour flow cytometric analysis, we found increased numbers of B cells co-expressing the pan-T cell marker CD5 and the B cell marker CD19 in cerebrospinal fluid (CSF) of 21 patients with multiple sclerosis (MS), compared with 17 control subjects with muscular tension headache. Only one patient with MS, but nine controls lacked CD5+ B cells in CSF. This difference was not observed in peripheral blood. Numbers of CD5+19+ B cells were increased in CSF compared with blood in MS, but not in the controls. In both groups, CD5+19+ B cells were not restricted to small resting lymphocytes, but were also found among larger-sized lymphocytes. The relative density of CD5 molecules and of CD19 molecules was lower in CD5+19+ than in CD5-19+ B cells and CD5+19- T cells. CD5+ B cells are assumed to be responsible for autoantibody production, and our results suggest a pathogenetic role of such cells, predominantly within the central nervous system, in MS.  相似文献   
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