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R Figueroa-Colon FA Franklin JY Lee R Aldridge L Alexander 《Canadian Metallurgical Quarterly》1997,90(8):806-813
A solid-phase, monoclonal antibody-based ELISA was set up to quantitate group 5 allergens in pollen extracts of wild and cultivated Pooideae grasses. The method was able to evaluate group 5 concentration in mass units with a sensitivity in the ng/ml range and a practical working range of 1-100 ng/ml. The group 5 ELISA was compared with rocket immunoelectrophoresis for determination of allergen levels in several Phleum pratense extracts, and a very good quantitative correlation was found (r = 0.98; P < 0.0001). A highly significant correlation (r > 0.8) was also obtained in comparing allergenic potency determined by RAST inhibition to group 5 content in several wild and cultivated grass species. The results proved the usefulness of the method in the standardization of Pooideae pollen extracts employed in diagnosis and treatment. 相似文献
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JO Park HC Chung JY Cho SY Rha NC You JH Kim SH Noh CB Kim JS Min BS Kim JK Roh 《Canadian Metallurgical Quarterly》1997,20(5):484-489
About one-third of patients with gastric cancer are unresectable at the time of diagnosis. Their median survival is < 6 months, with a grave prognosis. The purpose of this study was to assess the efficacy of a modified FAM (mFAM) regimen in advanced gastric cancer. We retrospectively reviewed the clinical records of 409 advanced gastric cancer patients who had not received curative surgery. Among 409 patients, 202 patients were treated with an mFAM regimen (infusional 5-FU + doxorubocin + mitomycin-C), and 207 patients received no chemotherapy (control group). No differences were found in clinical parameters between the two groups. The 1-year survival rates were 34.1% for the mFAM-treated group and 22.5% for the control group (p = 0.0135). In subset analysis, a higher 1-year survival rate was demonstrated in patients with mFAM and palliative surgery. Of the 154 evaluable patients in the mFAM-treated group, the response rate was 17.5%. In these patients, median response duration was 30 weeks, and progression-free survival was 23 weeks. Overall toxicity of mFAM regimen was relatively tolerable and reversible. In conclusion, FAM combination chemotherapy, which has been used as a standard therapy, prolonged survival after modification of the administration schedule and combination with palliative surgery. A prospective randomized study is warranted to confirm this conclusion from our retrospective study. 相似文献
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JY Kang KG Yeoh KY Ho R Guan TP Lim SH Quak A Wee D Teo YW Ong 《Canadian Metallurgical Quarterly》1997,12(9-10):655-659
The aim of this study was to determine, first, whether racial differences exist in the seroprevalence of Helicobacter pylori infection in Singapore, and second, whether these differences correlate with racial differences in peptic ulcer frequency. A commercial serological test for immunoglobulin (Ig)G antibody to H. pylori which was 90% sensitive and 83% specific in our population was used to screen 403 adult blood donors of Chinese, Malay and Indian origin, aged between 15-60 years. Serum specimens from 84 paediatric patients admitted to the Paediatrics Department, National University of Singapore, with non-gastroenterological illnesses were also tested. In all three races, seroprevalence of H. pylori increased with age. Indians have the highest prevalence of infection followed by Chinese and Malays. Peptic ulcer prevalences are known to be highest in Chinese, followed by Indians and Malays. The Malays have the lowest prevalence of H. pylori and peptic ulcer among the three races in Singapore. Indians have a higher prevalence of H. pylori antibodies but a lower frequency of peptic ulcer than the Chinese. Racial differences in peptic ulcer frequency between Chinese and Indians are not explained by the prevalence of H. pylori infection; other environmental or genetic factors may be involved. 相似文献
126.
DS De Wachter PR Verdonck JY De Vos RO Hombrouckx 《Canadian Metallurgical Quarterly》1997,20(7):366-370
To investigate the haemolysis in haemodialysis cannulae, an in-vitro set up is built, using a unipuncture dialysis system. This system is connected to a bag with fresh calf's blood, by the cannula under test, mounted in a large bloodline (5 mm diameter). The blood characteristics are kept constant by means of a bicarbonate dialysate in the dialyser. During a 6 h period, haematological parameters are regularly samples. Flow through the cannulae is recorded, which is about 500 mL/min. Four different cannulae are tested and compared to the results obtained without any cannula in the circuit. In all cases a linear increase in plasma free haemoglobin levels is found after 6 h. The cannulae can be ranked from 8F catheter over 13G, 14G to 16G cannula, the latter producing the highest degree of haemolysis. When using plastic cannulae at high blood flows, their haemolytic effect may not be neglected. 相似文献
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High intensity focused ultrasound (HIFU) is an effective technique for creating coagulative necrotic lesions in biological tissue, with a view to treating localized tumors. Although good results have already been obtained, notably in urology, current systems lack a real time monitoring system to check the efficacy of the treatment procedures. This study describes the development and assessment of a noninvasive system for making local measurements of attentuation variations during HIFU treatment procedures. An apparatus (Ablatherm, Edap-Technomed, France), combining a 2.5 MHz therapeutic transducer and a 5.5 MHz twin plane imaging probe (connected to an ultrasound scanner), was used to produce lesions. The rf signals needed to calculate the attenuation were recorded as outputs from the ultrasound scanner, before and after the high intensity firing sequences, which were performed on ten pieces of porcine liver. Each firing sequence involved producing a lesion volume comprising 42 individual lesions. A number of recordings were also made without producing lesions, in order to test the reproducibility of the measurements. The attenuation function was evaluated locally using the centroid and the multinarrowband methods. Initially, changes in the integrated attenuation alpha (mean attenuation in the 4-7 MHz range) and the attenuation slope beta were examined for the lesion volume. beta values did not vary significantly within this range, whereas alpha values varied significantly (in the region of 86% of the initial level) in comparison to measurements performed without forming lesions. The differential attenuation delta alpha (representing local variations in alpha) was subsequently used to generate images revealing the lesion areas. There was a strong similarity between these 'delta alpha images' and the lesion volumes defined by the operator. 'delta alpha images' offer several advantages over existing attenuation imaging techniques. Any problems related to the heterogeneity of the medium are eliminated, since only the change in attenuation is taken into account. Furthermore, there is no need to compensate for diffraction when estimating delta alpha, as the rf signals are captured in exactly the same positions before and after treatment. This technique can be used during in vivo treatment procedures. It can be implemented in real time, since the computational algorithms (based primarily on FFT calculations) are very fast. The technique should provide clinical practitioners with valuable qualitative and quantitative information for use in HIFU ultrasound surgery. 相似文献
128.
The role of pulmonary surfactant proteins in the pathogenesis of airway inflammation and the impact on asthma has not been elucidated. This study was designed to examine the effect of surfactant proteins A (SP-A) and D (SP-D) on phytohemagglutinin- (PHA) and mite allergen Dermatophagoides pteronyssinus (Der p)-induced histamine release and the proliferation of peripheral blood mononuclear cells (PBMC) in children with asthma in stable condition (n = 21), asthmatic children during acute attacks (n = 9), and age-matched control subjects (n = 7). The results show that SP-A and SP-D were able to reduce the incorporation of [3H]thymidine into PBMC in a dose-dependent manner. In addition to the intact, native SP-A and SP-D proteins, a recombinant peptide composed of the neck and carbohydrate recognition domain (CRD) of SP-D [SP-D(N/CRD)] was also found to have the same suppressive effect on lymphocyte proliferation. This effect was abolished by the presence of 100 mM mannose (for SP-A) or maltose (for SP-D) in the culture medium, which suggested that the CRD regions of SP-A and SP-D may interact with the carbohydrate structures on the surface molecules of lymphocytes. The inhibitory effects of surfactant proteins on PHA- and Der p-stimulated lymphocyte responses were observed in stable asthmatic children and age-matched control subjects, while only a mild suppression (< 25%) was seen in activated lymphocytes derived from asthmatic children with acute attacks. SP-A and SP-D were also found to inhibit allergen-induced histamine release, in a dose-dependent manner, in the diluted whole blood of asthmatic children. We conclude that both SP-A and SP-D can inhibit histamine release in the early phase of allergen provocation and suppress lymphocyte proliferation in the late phase of bronchial inflammation, the two essential steps in the development of asthmatic symptoms. It appears that SP-A and SP-D may be protective against the pathogenesis of asthma. 相似文献
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