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201.
A case of 55 years old woman with "hot" right lobe toxic thyroid nodule, presenting with paroxysmal atrial fibrillation, and therefore treated with 131I 666MBq (18 mCi) is described. After six years she became pyrexic and suffered of severe cough proxyisms. The fine needle biopsy of the above nodule showed the presence of anaplastic thyroid carcinoma. Strumectomy followed by local radiotherapy resulted in complete disappearence of all symptoms. The microscopic of the removed thyroid tissue confirmed the above diagnosis. After 22 months' observation the patient remained in good general condition. The possible reasons for the development of the thyroid carcinoma in this case are discussed. 相似文献
202.
Normal endothelin 1/2 levels and their correlation with age were evaluated. For clinical application of the endothelin 1/2 RIA test, optimum storage conditions were investigated. Plasma endothelin 1/2 (ET) levels were measured in 36 healthy blood donors, mostly males, of mean age 36 +/- 8 years, subdivided into three age groups: 17-30, 31-40 and above 40 years old. The mean normal ET levels in the three age groups, and corresponding standard deviations, were: 0.58 +/- 0.19, 0.62 +/- 0.31, and 0.80 +/- 0.28 fmol/ml, respectively. The mean ET level for the whole normal population was 0.66 +/- 0.28 fmol/ml. Only differences between mean ET levels for the first and last groups were statistically significant (p < 0.05). Differences between mean ET levels in smokers (53% of total population) and non-smokers, women and men, irrespective of age, were found not to be statistically significant. At this stage of our work, we conclude that other factors than age alone play a role in enhancing ET levels above the age of 41 years. In our study of optimum storage conditions for endothelin 1/2, we found that after one week of storage at -24 degrees C the mean level of ET measured in frozen plasma dropped to 85% of the initial activity, while after the same period the respective decrease in ET activity in frozen extracts was 49%. Over the next two weeks, ET levels in plasma and extracts dropped to 57% and 32% of "zero time" activities, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
203.
204.
Urinary digoxin-like immunoreactive factor (DLIF), arginine-vasopressin (AVP) and other urinary parameters were investigated under normal conditions and after the i.p. injection of the following solutions: distilled water, isotonic and hypertonic NaCl, NaHCO3, KCl and urea, at a rate of 3 ml/100 g body weight. The measurement of digoxin-like immunoreactivity by two different radioimmunoassays showed that DLIF was stimulated by all volume loads regardless of the presence or absence of osmolar compounds. This dissociation between DLIF and urinary sodium excretion suggests that DLIF may not constitute the natriuretic hormone. Moreover, a dissociation between DLIF and AVP excretion also were found, which speaks against the hypothesis of a common mechanism of stimulation for both substances. 相似文献
205.
A conserved coronavirus epitope, critical in virus neutralization, mimicked by internal-image monoclonal anti-idiotypic antibodies.
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Monoclonal antibody (MAb) 6A.C3 neutralizes transmissible gastroenteritis coronavirus (TGEV) and is specific for a conserved epitope within subsite Ac of the spike (S) glycoprotein of TGEV. Six hybridomas secreting anti-idiotypic (Ab2) MAbs specific for MAb 6A.C3 (Ab1) have been selected. All six MAbs inhibited the binding of Ab1 to TGEV and specifically cross-linked MAb1-6A.C3. Four of these hybridomas secreted gamma-type anti-idiotypic MAbs. The other two Ab2s (MAbs 9A.G3 and 9C.E11) were recognized by TGEV-specific antiserum induced in two species. This binding was inhibited by viruses of the TGEV group but not by serologically unrelated coronaviruses. These results indicate that MAb2-9A.G3 and MAb2-9C.E11 mimic an antigenic determinant present on the TGEV surface, and they were classified as beta-type ("internal-image") MAbs. TGEV-binding Ab3 antiserum was induced in 100% of mice immunized with the two beta-type MAb2s and in 25 to 50% of mice immunized with gamma-type MAb2. Both beta- and gamma-type Ab2s induced neutralizing Ab3 antibodies in mice that were mainly directed to antigenic subsite Ac of the S protein. 相似文献
206.
The aim of the study was to determine a loss of nitrogen compounds with sweat in sauna and to estimate their plasma concentration. Sweat was collided during 30 min stay in sauna. Blood was taken before and immediately after the sauna. Concentrations of ammonia, urea, creatinine and uric acid were determined in the both fluids. It has been found, that the concentration of ammonia in sweat exceeds, that in plasma by 77 times. Ammonia plasma concentration following sauna increased by about 60%. Sweat urea concentration exceeded that in plasma by 3.5 times. Plasma urea concentration was significantly reduced after sauna. Sweat creatinine concentration was about two times higher than that in plasma. No uric acid was detected in sweat. Sweating did not affect plasma creatinine and uric acid concentrations. Results indicate that considerable amount of nitrogen is lost with sweat during sauna. 相似文献
207.
Short-term effects of carbon dioxide on carnation callus cell respiration 总被引:10,自引:6,他引:4
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The addition of potassium bicarbonate to the electrode cuvette immediately stimulated the rate of dark O2 uptake of photomixotrophic and heterotrophic carnation (Dianthus caryophyllus L.) callus, of Elodea canadensis (Michx) leaves, and of other plant tissues. This phenomenon occurred at pH values lower than 7.2 to 7.8, and the stimulation depended on the concentration of gaseous CO2 in the solution. These stimulatory responses lasted several minutes and then decreased, but additional bicarbonate or gaseous CO2 again stimulated respiration, suggesting a reversible effect. Carbonic anhydrase in the solution increased the stimulatory effect of potassium bicarbonate. The CO2/bicarbonate dependent stimulation of respiration did not occur in animal tissues such as rat diaphragm and isolated hepatocytes, and was inhibited by salicylhydroxamic acid in carnation callus cells and E. canadensis leaves. This suggested that the alternative oxidase was engaged during the stimulation in plant tissues. The cytochrome pathway was severely inhibited by CO2/bicarbonate either in the absence or in the presence of the uncoupler carbonylcyanide m-chlorophenyl hydrazone. The activity of cytochrome c oxidase of callus tissue homogenates was also inhibited by CO2/bicarbonate. The results suggested that high carbon dioxide levels (mainly free CO2) partially inhibited the cytochrome pathway (apparently at the oxidase level), and this block in electron transport elicited a large transient engagement of the alternative oxidase when present uninhibited. 相似文献
208.
The influence of human plasma proteins (fibrinogen, albumin and fibronectin) on the adherence of Staphylococcus epidermis to teflon, polyethylene, polycarbonate and bovine pericardium was studied in an in vitro quantitative assay by scintillation counting. Bacterial adhesion was generally reduced by the presence of protein during the adherence assay except in the case of bovine pericardium, in which adherence remained almost unaffected. The effect of these plasma proteins on bacterial surface properties resulted in strong increases of surface charge as measured by ion-exchange chromatography and with no effect on hydrophobicity, estimated as contact angles. Adherence was not found to be correlated with these two properties, suggesting that bacteria-surface interactions must not be simplified to the influence of interfacial forces. 相似文献
209.
C M Contreras M L Marván H Lara-Morales A Barradas L Chacón M A Guzmán-Sáenz C Márquez Flores 《Boletín de estudios médicos y biológicos》1991,39(1-4):3-8
An increased firing rate in lateral septal nuclei (LSN) appears in urethane-anesthetized rats after several acute drug and non-drug human antidepressant treatments. A still more pronounced increase in firing rate is produced in LSN after clomipramine (CMI) long-term treatment. In spite of urethane is a widely used anesthetic for single unit extracellular recordings, it modifies evoked potentials wave-form. Therefore, present study discards urethane interaction with CMI in LSN single unit extracellular recordings. CMI was acutely injected (1.25 mg/kg: IP) either to urethane-anesthetized, or non-anesthetized encephale-isolé rats. The CMI treated groups showed higher rates of firing in LSN regardless of the use of general anesthesia during recordings. Another group of urethane-anesthetized rats received intracerebroventricular (ICV) microinjections of CMI (100 micrograms/10 microliters/1 min). An amount of 42.8% of LSN-recorded neurons responded with a long-lasting increased firing rate. Results discard urethane and CMI interactions. Additionally, systemic actions of CMI on firing rate of LSN are reproduced by ICV/route microinjections. 相似文献
210.
Evolution ofMHC polymorphism: Extensive sharing of polymorphic sequence motifs between human and bovine DRB alleles 总被引:4,自引:0,他引:4
Leif Andersson Sunna Sigurdardóttir Carina Borsch Kenth Gustafsson 《Immunogenetics》1991,33(3):188-193
The evolution ofMHC polymorphism has been studied by comparing the amino acid and nucleotide sequences of 14 bovine and 32 humanDRB alleles. The comparison revealed an extensive sharing of polymorphic sequence motifs in the two species. Almost identical sets of residues were found at several highly polymorphic amino acid positions in the putative antigen recognition site. Consequently, certain bovine alleles were found to be more similar to certain human alleles than to other bovine alleles. In contrast, the frequencies of silent nucleotide substitutions were found to be much higher in comparisons between species than within species implying that none of the human or bovine DRB alleles originated before the divergence of these distantly related species. The results suggest that the observed similarity inDRB polymorphism is due to convergent evolution and possibly the sharing of short ancestral sequence motifs. However, the relative role of the latter mechanism is difficult to assess due to the biased base composition in the first domain exon of polymorphic class 11 genes. The frequency of silent substitutions betweenDRB alleles was markedly lower in cattle than in man suggesting that theDRB diversity has evolved more rapidly in the former species. 相似文献