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101.
J Laine L Krogerus S Sarna H Jalanko K R?nnholm C Holmberg 《Canadian Metallurgical Quarterly》1996,61(6):898-903
OBJECTIVE: To determine primary and secondary antibody responses in children with hypogammaglobulinemia attributed to corticosteroid use. RESULTS: In seven patients with steroid-dependent asthma and significant hypogammaglobulinemia (IgG concentration, 275 to 443 mg/dl), antibody responses to protein and polysaccharide antigens were shown to be normal, as were primary and secondary responses to a neoantigen, bacteriophage phi X174. CONCLUSIONS: Patients with asthma, and with hypogammaglobulinemia resulting from steroid therapy, have normal humoral immunity, and immunoglobulin replacement therapy is not indicated. 相似文献
102.
Rats transgenic for HLA-B27 and human beta 2-microglobulin develop a spontaneous, multisystem, inflammatory disease that resembles human B27-associated disease and that involves the gut mucosa. This model predominantly affects the colon and is characterized by an extensive infiltration of the mucosa by inflammatory cells, largely composed of mononuclear cells. In addition, an increased plasma level of nitric oxide (NO)-derived metabolites was described in this model. Deficiency in the anti-inflammatory cytokine, interleukin-10 (IL-10), leads to the development of colitis in IL-10 knockout mice, suggesting that IL-10 plays a major role in the control of gut inflammation. The objectives of this work were to study the mechanisms of the inflammatory bowel disease (IBD) in HLA-B27 rats and to determine the effects of treatment with IL-10. The 33-3 line of HLA-B27 recombinant rats with established disease was treated in two consecutive experiments with murine recombinant IL-10 for five weeks. Assessment of the effect of this treatment was performed, based on clinical, histological and biological (myeloperoxidase and inducible NO synthase activities; tumor necrosis factor-alpha, interferon-delta, CD3, iNOS and beta-actin mRNA expression. In 33-3 rats with established disease, mesenteric lymph nodes were hyperplastic, and colonic cellularity and MPO and iNOS activities in the colonic mucosa were increased without any detectable effects of IL-10 administration. IFN-gamma and iNOS mRNA were only detected in the colon of transgenic rats. Despite a lack of effect on disease expression, IL-10 strikingly reduced the level of IFN-gamma mRNA in gut mucosa. Up-regulation of IFN-gamma mRNA suggests that the IBD of HLA-B27 rats is mediated by T-helper 1 lymphocytes. Sustained administration of IL-10, in HLA-B27 rats with established disease, efficiently inhibited IFN-gamma mRNA expression but did not influence disease expression: these results indicate that IFN-gamma may exert a critical role at an earlier stage of the disease rather in the maintenance of the lesions. 相似文献
103.
S Sj?gren M Ingan?s A Lindgren L Holmberg J Bergh 《Canadian Metallurgical Quarterly》1998,16(2):462-469
PURPOSE: To investigate the prognostic and predictive value of c-erbB-2 overexpression in breast cancer in relation to other prognostic markers. PATIENTS AND METHODS: Paraffin-embedded tumors from 315 consecutive primary breast cancer patients were screened for c-erbB-2 protein (p185) overexpression by immunohistochemistry using the monoclonal antibody CB11. RESULTS: c-erbB-2 protein overexpression was detected in 19% of tumors and was associated with shorter 5-year overall survival (OAS) rate compared with c-erbB-2-negative cases in the total patient material (58% and 77%, respectively; P = .004) and in the 96 node-positive patients (31% and 61%, respectively; P = .02), but not in node-negative patients. For 47 node-positive patients treated with adjuvant tamoxifen and radiotherapy, the 5-year OAS was 13% for c-erbB-2 overexpression and 75% for c-erbB-2-negative patients (P = .00004). The frequency of c-erbB-2 overexpression decreased with age at diagnosis. The prognostic value of c-erbB-2 on OAS was independent of age, node status, tumor size, histopathologic grade, hormone receptor status, S phase, p53 status, and adjuvant treatment. c-erbB-2 status added prognostic information to p53-negative and low S-phase cases, but not to p53-positive and high S-phase cases. Correspondingly, these only added information to c-erbB-2-negative cases. CONCLUSION: c-erbB-2 protein overexpression may have a predictive value with regard to adjuvant therapy in node-positive patients, for whom adjuvant tamoxifen with radiotherapy appears insufficient in the presence of c-erbB-2 overexpression. Combination of conventional and newer tumor markers may identify patients with a worse prognosis within groups with a generally favorable prognosis. 相似文献
104.
Examined the behavior of a chaotic circuit where one of the components has been replaced by a chemical sensor. The response of the sensor is manifested as a change in the attractor of the circuit. Furthermore, with a proper operating point, a small response of the sensor causes a change in the attractor of the circuit within a time much shorter than the normally defined response time of the sensor. This technique unites sensors and data processing as one combined unit in a unique fashion. 相似文献
105.
The secondary structure of mouse Ehrlich ascites 18S, 5.8S and 28S ribosomal RNA in situ was investigated by chemical modification using dimethyl sulphate and 1-cyclohexyl-3-(morpholinoethyl) carbodiimide metho-p-toluene sulphonate. These reagents specifically modify unpaired bases in the RNA. The reactive bases were localized by primer extension followed by gel electrophoresis. The three rRNA species were equally accessible for modification i.e. approximately 10% of the nucleotides were reactive. The experimental data support the theoretical secondary structure models proposed for 18S and 5.8/28S rRNA as almost all modified bases were located in putative single-strand regions of the rRNAs or in helical regions that could be expected to undergo dynamic breathing. However, deviations from the suggested models were found in both 18S and 28S rRNA. In 18S rRNA some putative helices in the 5'-domain were extensively modified by the single-strand specific reagents as was one of the suggested helices in domain III of 28S rRNA. Of the four eukaryote specific expansion segments present in mouse Ehrlich ascites cell 28S rRNA, segments I and III were only partly available for modification while segments II and IV showed average to high modification. 相似文献
106.
Experimental kinetic data on n-heptane pyrolytic and catalytic steam cracking, and product distribution data were obtained at reaction temperatures from 700° to 800°C at atmospheric pressure. The overall thermal cracking of n-heptane was compared to the cracking in presence of the basic catalysts MgO, CaO (low surface quicklime), and calcined dolomites. 相似文献
107.
Per Holmberg 《电子与电脑》2004,(1):46-49
ASIC的非重复研发成本(NRE)与研发时间正迅速攀升.在0.13微米领域为例,不但非重复研发成本(NRE)甚至高达1000万美元以上,设计一套ASIC芯片通常必须要耗费12至18个月的时间.此外,在开芯片的设计规格时,必须考虑支持不同应用的调整性(Adaptability).调整性的需求来自于许多因素,其中包括: 相似文献
108.
Influence of material properties and stamping conditions on the stiffness and static dent resistance of automotive panels 总被引:7,自引:0,他引:7
The use of thinner sheets and the introduction of new materials has meant that the stiffness and dent resistance of exterior panels has become more focused in the automotive industry during the last years. The objective of this study was to investigate the influence of material choice and the effect of varying stamping process conditions on the stiffness and static dent resistance of automotive panels. The experiments were performed on a double-curved panel. Four different materials were included in the study: an aluminium grade, a mild steel, a high-strength steel and a stainless steel. For each material, two different stamping-process conditions were adopted to obtain different strain, stress and thinning distributions in the panels. The same stamping process conditions were applied to all four materials. It can be concluded that the material grade significantly influences the static dent properties. The high-strength steel showed considerably better dent resistance than the other materials. The aluminium panels had slightly better dent resistance than the mild steel panels, although having much lower stiffness. The stainless steel grade had the lowest dent resistance, despite its high yield stress. An effect of the stamping process conditions was also found. Increased blankholding, with consequent increased strain levels in the panels, was generally beneficial to the static dent resistance. The experiments show very little scatter, indicating that the testing methodology developed worked satisfactorily. 相似文献
109.
N. Anders Holmberg 《国际钢铁研究》1998,69(1):22-27
This paper presents a new method for metal distribution onto the belt of a horizontal single belt strip caster. Water and liquid tin have been used to study the flow conditions in the feeding zone on the conveyor belt. Tests of a method presented in literature for metal distribution have been conducted and a new method that uses multiple parallel jets in order to obtain stable feeding conditions have been tested. This method gives a controlled way of maintaining a continuous liquid film and it also has a stable meniscus. The freezing problem with a triple point will also be eliminated by use of this method. 相似文献
110.
Although the transfer of free flaps is nowadays accomplished with an increasing degree of safety, thrombosis of the microvascular anastomoses is still a problem. In order to avoid delay in re-operating, various methods for objective blood flow monitoring have been tried, among them Laser Doppler Flowmetry (LDF). When one reviews the literature, it is apparent that opinions differ about whether or not LDF is a reliable technique for this purpose. To focus on the need to interpret continuous recordings, this paper reports our findings in six latissimus dorsi free flaps chosen from our series of LDF monitoring procedures. One uneventful flap, no. 1, had an immediate postoperative LDF value of 4.5 perfusion units (PU). LDF values improved during the recovery period and the graphic recording showed fluctuations due to normal physiological variations of the blood flow in the flap. Another uneventful flap, no. 4, showed the same pattern, though at an appreciably lower level, 2 PU, on average. Flap no. 2 had an acceptably high value of 3.5 PU despite suffering a venous thrombosis. However, the LDF recording showed no fluctuations and the value declined gradually. Another flap, no. 3, showed fluctuations and blood flow was normal although the value decreased to 2.5 PU. In flap no. 5, any value between 2 and 3.5 PU could be obtained merely by adjusting the position of the probe in the holder. In no. 6, the LDF value suddenly dropped, accompanied by a decrease in the total amount of backscattered light, indicating venous obstruction which was confirmed at re-operation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献