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11.
12.
Duda  D.  Lorenz  W.  Menke  H.  Rugeles  M. S.  Stinner  B.  Weber  D.  Kapp  B.  Junginger  Th.  Dick  W. 《Inflammation research》1992,36(2):C149-C154

Histamine release events were shown in a prospective randomized controlled trial in patients undergoing elective general surgery with an extraordinarily high incidence: 73 per cent. This high incidence was explained by several factors: — the sample size which was much greater than in previous studies — the improved plasma histamine assay — the precise definition of histamine release in clinical conditions and its measurement at the top of Bateman functions — the standardized induction of anaesthesia and preparation of the surgical patient — and finally the considerable number of cancer patients since more than 60% of the reactions >5 ng/ml occurred in this group which comprised only 20% of the study population.

Two cases of life-threatening anaphylactoid reactions occurred in this trial corresponding to an incidence of 1 per cent. This was — again — very high compared to previous epidemiological studies. Both cases were again cancer patients and occurred in the placebo group — information given by the external study advisory group for further treatment of the individual patient.

The data on the high incidence of histamine release including the high incidence of life-threatening reactions favourrationally a preoperative H1 +H2-prophylaxis with the drugs used in this study: dimetindene and cimetidine. The question of the incidence was one of the unsettled problems which led to this trial. Analysis of the first 180 patients already answered this question more than we had ever expected.

  相似文献   
13.
Six commercially available bacterial identification products were tested with Vibrio alginolyticus (12 strains), V. cholerae (30 strains), Photobacterium (Vibrio) damselae (10 strains), V. fluvialis (10 strains), V. furnissii (4 strains), V. hollisae (10 strains), V. metschnikovii (9 strains), V. mimicus (10 strains), V. parahaemolyticus (30 strains), and V. vulnificus (10 strains) to determine the accuracy of each system for identification. The products included API 20E, Crystal E/NF, MicroScan Neg ID2 and Rapid Neg ID3, and Vitek GNI+ and ID-GNB. Each product was tested only with those species that were listed in its database. Overall, the systems correctly identified 63.9, 80.9, 63.1, 73.6, 73.5, and 77.7% of the isolates to species level, respectively. Error rates ranged from 0.8% for the API 20E to 10.4% for the Rapid Neg ID3. The API 20E gave "no identification" for 13.1% of the isolates, while the Neg ID2, GNI+, ID-GNB, and Crystal were unable to identify 1.8, 2.9, 5.0, and 6.9%, respectively. For V. cholerae, specifically, accuracy ranged from 50.0 to 96.7%, with the API 20E having the worst performance and Crystal having the best. V. fluvialis presented the biggest challenge for the API 20E and the GNI+, with probabilities averaging 10%, while V. mimicus was a major problem with the Crystal E/NF, which identified none of the strains correctly. With the Neg ID2, correct answers were often obtained only after a modified inoculation of the panel with a bacterial suspension prepared with 0.85% NaCl. Additional tests required for identification often included growth in the absence of NaCl, which is not readily available in most clinical laboratories. The only product to correctly identify at least 90% of V. cholerae strains was the Crystal E/NF, and only three of the six products, the API 20E and both of the Vitek cards, correctly identified more than 90% of the V. parahaemolyticus strains. Thus, extreme care must be taken in the interpretation of answers from these six commercially available systems for the identification of Vibrio species.  相似文献   
14.
The anionic polymerization of exo-3,4,5-trithiatetracyclo[5.5.1.O2,6.O8,12]tridec-10-ene ( 1 ) in bulk and/or in aromatic solvents (benzene, toluene) was studied. The polymerization was initiated with sodium benzenethiolate (sodium cation complexed with dibenzo-18-crown-6). Polymers with high-molecular weights were obtained (M n ≈ 105, osmometrically). The polymerization was found to be living and reversible; the equilibrium monomer concentration increases with the temperature. The ceilling temperature was estimated as 167°C. The thermodynamic data of the polymerization in toluene was determined and compared with those of the polymerization of exo-3,4,5-trithiatricyclo[5.2.O2,6]decane. The standard enthalpy ΔH = ?(6,6 ± 0,6)kJ · mol 1 and entropy ΔS = ?(29,3 ± 2,1)J · mol 1 · K 1 of the polymerization of 1 were evaluated from the temperature dependence of the equilibrium monomer concentration, determined dilatometrically.  相似文献   
15.
K Tóth  E Duda 《Acta virologica》1991,35(2):165-173
Isolated envelope proteins of Newcastle disease virus (NDV) were inserted into the lipid bilayer of artificial vesicles to create a viral envelope-like structure. The structure-containing viral antigens at high density elicited a strong immune response, in contrast to purified viral proteins. The artificial envelopes or immunosomes possessed several advantageous properties when used as vaccines. They elicited a faster response and the immunity lasted longer in animals treated with these vesicles than in controls vaccinated with envelope proteins in combination with traditional adjuvants. A further useful feature of the artificial envelopes is that no inflammatory lesions develop at the site of their injection.  相似文献   
16.
This goal of this study was to assess the initial feasibility and efficacy of a play-based intervention targeting executive functions (EF) and parent–child relationships in preschoolers compared with an active control group. Preschoolers with EF deficits (M age = 3.7 ± 0.47, predominantly White boys) and their parents were randomized to intervention (= 36) or active control (= 32) conditions. Child performance on EF tasks, parent and masked teacher ratings of EF and behavior, and masked clinician ratings of severity were collected at baseline and at 3 and 6 months postbaseline. Partial eta-squared effect sizes at .02 or higher comparing performance across the two groups was considered evidence of meaningful, albeit small, intervention effects. Intervention effects were observed for parent ratings of inattention, hyperactivity/impulsivity, and number/severity of problems experienced in various home situations, teacher ratings of severity of problems in various school situations, parent and teacher ratings of overall impairment, and clinician ratings of impairment. Intervention effects for functional improvements were maintained at the 6-month follow-up. No effect of the intervention was observed on the objective EF measures, although parent ratings of emotional control were improved for children in the intervention group. An intervention utilizing play-based activities targeting EF, when administered in a structured way by parents, is a promising approach for improving behavior in preschoolers with self-regulation deficits. More work is needed to investigate potential impact on EF and to disentangle mechanisms of action. It may be that the intervention’s focus on the structure and quality of parent–child interactions is a mediator of outcomes, rather than improved EFs.  相似文献   
17.
Differential expression of CD22 (Lyb8) on murine B cells   总被引:2,自引:0,他引:2  
Previous studies have established the distribution, biochemistryand functional attributes of human CD22, a B cell-restrictedglycoprotein. Recently, molecular cloning of the murine CD22equivalent revealed this molecule to be the same as the previouslydescribed Lyb8 alloantigen. Using the anti-Lyb8 mAb Cy34.1.2,the present report documents the expression patterns of CD22within the murine B cell compartment. The results demonstratethat in the bone marrow, murine CD22 is absent on the surfaceof pro-B cells, pre-B cells and newly emerging lgM+ B cells.CD22 is present at a low density on immature IgMhi B cells andfully expressed on mature recirculating B cells. In the periphery,murine CD22 is expressed at mature levels on all B cell subsetsincluding follicular, marginal zone, B1 and switched B cells.Further studies showed CD22 to be retained on activated murineB cells for extended periods. Finally, in combination with CD23and heat stable antigen, CD22 can be used to delineate the immaturesplenic B cells, and distinguish them from follicular and marginalzone cells. Together, the results demonstrate murine CD22 tobe a useful pan marker for all mature B cell subsets.  相似文献   
18.
Pseudopregnant, pregnant, and ovariectomized rabbits were utilized to study hormonal mediation of uterine epithelial surface negativity and glycocalyx morphology, and to seek local effects of blastocysts at sites of implantation. A loss of surface negativity [polycationic ferritin (PCF) binding] by day 6 of pregnancy or pseudopregnancy was noted, accompanied by alterations in epithelial glycocalyx. Uteri from estrous animals, or ovariectomized animals receiving oil or estradiol injections, bound PCF and exhibited a “globular” glycocalyx. Uteri from day 6 pseudopregnant or pregnant animals, or ovariectomized animals receiving progesterone injections, did not bind PCF or exhibit a globular glycocalyx. Both PCF binding and the globular character of the epithelial glycocalyx were sensitive to neuraminidase and trypsin treatment, suggesting sialoglycoprotein contribution to surface negativity. Implanting blastocysts had no detectable local effect on surface negativity, but did induce local reduction of epithelial glycocalyx at sites of implantation. Results of this study suggest that uterine epithelial glycocalyx alterations during the preimplantation period reflect a general response to prosgesterone stimulation, primarily qualtitative in nature, related to the acquisition of receptivity to ovo-implantation.  相似文献   
19.
Particle transport by oscillating flow in a tapered channel or in a tapered tube was computed from the complete equations of motion. These geometries represent a simplified model of the divergent flow field of the mammalian bronchial tree. The computed deformation profile of a line of particles, transported by the oscillatory motion, was compared with prior experimental results and analytical calculations. All three methods agree that there is transport in the divergent direction of the tube by an axial stream of steady drift in the core for moderately high frequency of oscillation (Womersley parameter in the range of 1 to 10). Bidirectional flow is established by an annular stream in the convergent direction, with no net flow on integral cycles of the oscillating fluid. At higher frequency, however, the steady stream transforms to a different shape in the tapered tube, with transport in the divergent direction nearer the walls of the tube, rather than in the core. Transport by the continuing streams with oscillatory ventilation of the respiratory tract should deliver medicinal aerosols of low intrinsic particle mobility to the peripheral regions of the lungs.  相似文献   
20.
Fujita  H; Doi  K; Chan  HP; Giger  ML; Duda  EE 《Radiology》1985,155(3):799-803
Two types of phantoms were developed with which to evaluate the overall performance of digital subtraction angiography (DSA) systems. A dynamic phantom, called a "fish bone" phantom, consists of polyethylene tubes that simulate blood vessels with various lesions, such as stenoses, ulcers, and aneurysms. With this phantom, washout curves were obtained representing the relationship between iodine content and time. It will be useful for qualitative assessment of DSA images, evaluation of different image-processing schemes, and studies of blood flow analysis. A static phantom, called a "C-D" phantom, can be used for measurement of quantitative contrast-detail (C-D) diagrams and for daily monitoring of DSA systems. This was constructed of tubes of seven different diameters (2.15-0.28 mm) and 14 different concentrations of contrast medium (100%-1.1% Renografin-76 [meglumine and sodium diatrizoate]). The C-D diagrams were determined from an observer performance study using C-D phantom images obtained at four different DSA settings.  相似文献   
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