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41.
The study was made of labyrinthine changes induced by lasix dehydration. Changes indicative of Meniere's disease were identified at comparison of the findings obtained by audiological lasix test, caloric optokinetic reactions. Four types of the nystagmic response in the bithermal lasix-test were determined. These reactions are helpful for more precise staging of the disease.  相似文献   
42.
From epithelial layer of rat intestinal were selected water soluble substances which influenced on Na+,K(+)-ATPase activity in 2 different ways: substances with molecular weight 220 Da, 400 Da were its activators, substance with weight 150 Da-inhibitor. Na+,K(+)-ATPase activators preincubated previously with Na+ acquire properties of inhibitors. Bivalent cations Ca, Mg remove this effect of Na-ions.  相似文献   
43.
The adaptive or pathologic responses of epithelial cells to inflammation are poorly characterized. The purpose of this study was to determine if epithelial cells cultured from clinically healthy and inflamed human gingival tissues express differences in proliferation rate and viability. Briefly, the inflammation status of individual donor sites from 101 patients was visually assessed at the time of periodontal surgery and categorized as either non-to-slightly inflamed, moderately inflamed, or severely inflamed. Discarded gingival tissues were then processed to obtain primary cell cultures, for which proliferation rates were determined by calculating the ratio of mean population doublings to the number of days required for cultures to become confluent. In general, the cells in the minimally inflamed group exhibited characteristics different than cells in the moderately and severely inflamed groups. Specifically, the cells obtained from clinical sites which exhibited no-to-slight inflammation had a significantly higher mean proliferation rate than cells in either the moderate inflammation group or the severe inflammation group. Based on trypan blue exclusion, the cells obtained from clinical sites which exhibited no-to-slight inflammation also were more viable than cells obtained from sites with moderate inflammation or severe inflammation. Microscopic evaluation showed morphological changes associated with increased inflammation. Cell cycle analysis by fluorescent-activated cell sorting (FACS) revealed a directly proportional relationship between the degree of inflammation and apoptosis, and a strong inversely proportional trend between the degree of inflammation and the numbers of cells undergoing mitosis. Taken together, these data suggest that epithelial cell proliferation and viability are inversely associated with the degree of gingival inflammation, once a putative "adaptive threshold" is exceeded. Elucidation of the underlying mechanisms will likely lead to improvements in clinical diagnosis and treatment.  相似文献   
44.
Amongst the elements which contributed to the success of the early lung transplants at the beginning of the 1980's we feel that the careful selection of candidates probably played a predominant role. If some of the selection criteria initially described remain somewhat intangible, others have either been eased or have been invalidated. The experience acquired over the last 15 years has enabled to precise the optimal moment to include patients on the waiting list and to refine the choice for the type of surgical procedure according to the underlying disease. This article aims to review the different selection criteria for candidates for transplantation and stresses those which have recently undergone change.  相似文献   
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The erythroleukaemic cell line TF-1, infected with either the pBabe neo retrovirus or the retrovirus bearing the human erythropoietin (hEpo) gene, developed three growth factor-independent clones. Erythropoietin (Epo), interleukin-3 (IL-3) and granulocyte-macrophage colony stimulating factor (GM-CSF) accelerated the proliferation of these clones. Autonomous growth of the clones was independent of Epo because it was not altered by Epo anti-sense oligonucleotides, nor was Epo detectable in culture supernatants. Cells from the mutant clones could not be induced by Epo to express glycophorin A and haemoglobin synthesis was markedly reduced. Haemin reversed the block in Epo-induced haemoglobin synthesis. Acquisition of growth factor-independence appears to be linked with the selective loss of differentiation capacity. These cells may provide a useful model for the study of the mechanisms involved in leukaemic transformation.  相似文献   
47.
BACKGROUND: Recently, endoaneurysomorrhaphy has been proposed as a more physiologic repair of postinfarction left ventricular aneurysm than is linear repair. There are only a few studies comparing the short-term and long-term results of the two techniques. METHODS: Clinical outcomes and echocardiographic measurements of left ventricular volume and sphericity in 27 patients who underwent endoaneurysmorrhaphy were compared with those in 20 patients who had linear repair. RESULTS: The two groups were matched with respect to age, gender, comorbid risk factors, functional class, urgency of the operation, and concomitant procedures. Preoperatively, left ventricular ejection fraction was lower in the endoaneurysmorrhaphy group (0.25 +/- 0.08 versus 0.30 +/- 0.09; p = 0.03). Follow-up was available in 44 patients (94%) and ranged from 2 to 86 months (mean, 41.0 +/- 26.5 months). Thirty-day operative mortality, perioperative complications, 5-year survival, and freedom from cardiac death were similar. Early postoperative percentage increase in left ventricular ejection fraction was greater after endoaneurysmorrhaphy (0.51 +/- 0.64 versus 0.18 +/- 0.48; p = 0.036). Long-term functional improvement was significantly better in the endoaneurysmorrhaphy group: At the time of last follow-up, 88% of patients were in New York Heart Association class I/II, compared with 53% after linear repair (p = 0.01). There were no measurable differences between the groups with respect to left ventricular ejection fraction (0.28 +/- 0.11 versus 0.27 +/- 0.11; p = 0.90), left ventricular volume (171.6 +/- 59.1 versus 169.9 +/- 54.4 mL; p = 0.94), and sphericity index (0.61 +/- 0.09 versus 0.61 +/- 0.12; p = 1.0). CONCLUSIONS: Despite having a similar effect on left ventricular geometry, endoaneurysmorrhaphy resulted in a greater increase in postoperative left ventricular ejection fraction and a substantially improved long-term clinical outcome.  相似文献   
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The Rieske protein II (Schmidt et al., 1996, FEBS Lett. 388, 43-46) from the thermoacidophilic crenarcheon Sulfolobus acidocaldarius (DSM 639) was expressed in E. coli cells. The full length protein was strictly bound to the E. coli membranes and could only be removed by detergent treatment indicating the presence of a membrane anchor. The iron sulfur cluster was correctly inserted into a fraction of the full length protein and much more effectively into a soluble form created by the deletion of the 45 N-terminal amino acids. The soluble form of the protein displayed the typical spectroscopic properties of a respiratory Rieske protein. The midpoint potential was +375 mV determined by CD redox potentiometry. The presented data demonstrate that the structure of the recombinant protein is very similar or identical to the authentic protein making this a powerful model system for the studies of Rieske proteins by site directed mutagenesis.  相似文献   
50.
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