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11.
GB Lipford T Sparwasser M Bauer S Zimmermann ES Koch K Heeg H Wagner 《Canadian Metallurgical Quarterly》1997,27(12):3420-3426
Certain bacterial immunostimulatory (i.s.) DNA sequences containing unmethylated CpG motifs stimulate antigen-presenting cells (APC) to express a full complement of costimulatory molecules and to produce cytokines including interleukin (IL)-12 and tumor necrosis factor (TNF)-alpha. While IL-12 is key to their T helper cell (Th)1-promoting adjuvant activity, secretion of toxic levels of TNF-alpha is harmful in that it promotes toxic shock. Given the beneficial as well as harmful consequences of i.s. DNA, we investigated the possibility of identifying DNA sequences, i.e. CpG oligodeoxynucleotides (ODN) which differentially activate IL-12 versus TNF-alpha cytokine production in APC. Here, we describe an i.s. DNA sequence with these characteristics. While its potential to induce IL-12 is preserved, its ability to trigger TNF-alpha release is strongly curtailed both in vitro and in vivo. I.s. DNA could be segregated into lethal and non-lethal in a mouse toxic shock model. The non-toxic i.s. DNA was useful as an adjuvant, thus allowing cytotoxic T cell responses to the soluble protein ovalbumin and conferring a resistant Th 1 phenotype to BALB/c mice lethally infected with Leishmania major. This i.s. CpG motif may thus be prototypic for a useful immunostimulating DNA sequence that lacks harmful side effects. 相似文献
12.
Z Amma E Kis M Józan-Jilling G Wagner T Gesztesi 《Canadian Metallurgical Quarterly》1997,138(29):1859-1861
Two chronic haemodialyzed patients with digitalis intoxication are reported. One of them took digoxin 0.25 mg three times daily for an unknown period and the other took digitoxin 0.1 mg twice daily for two weeks. The symptoms of intoxication were mainly concealed by uremic syndrome. The diagnosis was established by noticed sinus bradycardia, first- and second-degree atrioventricular block in ECG and the determination of sera levels of glycosides (serum digoxin concentration was 7.36 ng/ml, serum digitoxin concentration was 46.5 ng/ml) in both cases. Considering the probable long elimination period of digitalis and the potentially life-threatening situation the patients were given digoxin-specific antibody (Fab) fragments with potassium replacement therapy. The symptoms disappeared within a few hours after therapy, side effects and rebound toxicity did not develop. In connection with these cases the aim of this report is to publish a method which can reverse the life-threatening digitalis intoxication in patients suffering from renal failure as well. As to the above method, the authors have not found any similar case reports in the Hungarian medical literature. 相似文献
13.
We have used Path Integral Monte Carlo to study the surface melting of molecular hydrogen. Density profiles perpendicular and parallel to the bare H2 surface are computed showing the formation of a liquid adlayer at 6 K, less than half the bulk melting temperature of para-hydrogen, 13.8 K. To estimate the onset temperature and depth of H2 surface melting we determine the static structure factor within the individual H2-layers for wave vectors in the plane and find no crystalline order down to 3 K in a partially filled H2 adlayer at the free surface. We find quantum effects amplify the melting point depression at the free H2 surface compared to bulk by a factor of five over classical Lennard-Jones solids and find that the zero-point fluctuations of molecules at the surface are much enhanced over their bulk values. We see vacancy formation in the solid before melting. 相似文献
14.
MI Matee EF Lyamuya E Simon EC Mbena C Kagoma LP Samaranayake F Scheutz 《Canadian Metallurgical Quarterly》1996,73(5):292-294
The present study, based on 158 HIV seropositives and 167 HIV seronegatives, demonstrates that saliva collected with the Omni-SAL device and tested with GACELISA (an IgG antibody capture ELISA) is an effective non-invasive alternative to serum for anti-HIV IgG antibody screening. The study also shows that a conventional serum Western blot kit can be used, with slight modifications, for confirmatory testing of saliva specimens. Collecting saliva with the Omni-SAL device had a very good acceptance rate among Tanzanian subjects, and although this diagnostic method is not yet known by the general public, 65% of the study participants preferred to give saliva instead of blood for HIV testing. 相似文献
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T. S. Shamirzaev A. I. Toropov A. K. Bakarov K. S. Zhuravlev A. Yu. Kobitski H. P. Wagner D. R. T. Zahn 《Semiconductors》2006,40(5):527-533
The stationary and time-resolved polariton radiation in ultrahigh quality AIGaAs layers have been studied. It has been found
that elastic exciton-exciton collisions lead to the appearance of a low-energy line of polariton radiation. We show that the
rate of exciton-to-polariton transitions caused by elastic exciton-exciton collisions is determined not only by the density
of the excitonic gas, but also by its temperature; this is in accordance with existing theoretical predictions.
The text was submitted by the authors in English. 相似文献
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We evaluated the effect of repeated administration of OC125 F(ab')2 fragments on cancer antigen (CA) 125 determination in 210 serum samples from 30 patients. We found falsely high CA 125 concentrations in 142 (68%) samples, using a homologous CA 125 enzyme immunoassay (EIA) with OC125 antibodies. The Truquant OV2 method, which involves two other murine antibodies, and the IMx CA 125 method, which uses sheep antibodies as capture antibodies, resulted in only slightly increased (false-positive) values in some samples with exceptionally high CA 125 EIA values. We measured falsely low CA 125 values in 37 (18%) samples with the Truquant OV2 method. Interferences could be eliminated by removal of serum IgG. Our results suggest that interferences are to some extent caused by anti-idiotypic IgG induced by OC125 administration. Assays involving nonmurine anti-CA 125 antibodies as capture antibodies seem to be most suited for CA 125 determination after OC125 treatment, but in every case an apparent increase of CA 125 after OC125 infusion should be validated. 相似文献
20.
T Higashiguchi PO Hasselgren K Wagner JE Fischer 《Canadian Metallurgical Quarterly》1993,17(4):307-314
The purpose of this study was to determine the etiologic factors of denture stomatitis. Fifteen subjects with clinical evidence of localized simple denture stomatitis, fifteen subjects without clinical signs of denture stomatitis, and forty-five subjects with clinical evidence of generalized simple denture stomatitis were investigated clinically and mycologically. Subjects were evaluated according to age, sex, duration of denture usage, smoking habits, frequency of denture brushing, overnight denture wearing, pH level of saliva and degree of candidal colonization and candidal formation. Salivary samples and swabs were taken from the palate and the mucosal surfaces of the dentures investigated mycologically in order to identify the yeast colonies. Smears were taken from the palate and investigated in order to identify candidal formation. No statistically significant relationship was found between denture stomatitis and age, sex, duration of denture usage, frequency of denture brushing, overnight denture wearing or pH level of saliva. There was however, a statistically significant relationship between denture stomatitis and denture hygiene, smoking habits, candidal colonization and candidal formation. 相似文献