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11.
M Plat J Fleischer T Herrmann U Plat A Lesche E M Grafe H Wolf U Reinhardt 《Folia haematologica (Leipzig, Germany : 1928)》1987,114(6):797-809
The total population affected with non-Hodgkin's lymphoma and treated by means of radiotherapy or combined radio-chemotherapy between 1960 and 1985 at the Medical Academy Dresden was analysed as to prognosis. 247 patients were classified according to the previous German scheme, 79 were subdivided on the basis of the recommendations laid down in the Kiel classification. The remission rates and survival curves achieved will stand out the comparison with international literature (remission rates of the low malignancy group amounted to 85.3 p.c. and those of the high malignancy group to 80.0 p.c.; the 5-years survival rates of the low malignancy group amounted to 61.9 p.c. and those of the high malignancy group to 41.7 p.c.). The influence of histology, clinical stage and involvement of organs is discussed on the basis of our results and informations obtained in literature. Our analysis confirms the high importance which must be attached to a common radiologic-internal outpatient-department for co-ordinating the diagnostic and therapeutical programme. 相似文献
12.
Nowadays, the MONOD conception is the foundation for modelling the growth-connected substrat consumption. The methods of the parameter estimation for μmax and Ks have a variable exactness. Using the experimental MONOD 's data [1] variable graphical and numerical methods are analyzed from the point of statistical view. Appropriate objective functions are proposed. 相似文献
13.
14.
The ability of Butyrivibrio fibrisolvens and other ruminal bacteria (6 species, 18 strains) to ferment a crude xylan from wheat straw or to ferment xylans from larchwood or oat spelts was studied. Liquid cultures were monitored for carbohydrate utilization, cell growth (protein), and fermentation acid production. B. fibrisolvens 49, H17c, AcTF2, and D1 grew almost as well on one or more of the xylans as they did on cellobiose-maltose. B. fibrisolvens 12, R28, A38, X10C34, ARD22a, and X6C61 exhibited moderate growth on xylans. Partial fermentation of xylans was observed with Bacteroides ruminicola B14, Bacteroides succinogenes S85, Ruminococcus albus 7, Ruminococcus flavefaciens C94 and FD1, and Succinivibrio dextrinosolvens 22B. All xylans tested appeared to have a small fraction of carbohydrate that supported low levels of growth of nonxylanolytic strains such as Selenomonas ruminantium HD4. Compared to growth on hexoses, the same array of fermentation acids was produced upon growth on xylans for most strains; however, reduced lactate levels were observed for B. fibrisolvens 49 and Selenomonas ruminantium HD4. Measurements of enzyme activities of B. fibrisolvens AcTF2, 49, H17c, and D1 indicated that the xylobiase activities were cell associated and that the xylanase activities were predominantly associated with the culture fluid. The pattern of expression of these enzymes varied both between strains and between the carbon sources on which the strains were grown. 相似文献
15.
Wolf Bertling 《Bioscience reports》1987,7(2):107-112
We used empty capsids ofpolyoma virus to transfer DNA fragments and DNA/protein complexes into human cells. We encapsulated labeled and unlabeled single stranded DNA fragments by viral capsids. A complex of DNA with a DNA binding protein, recA, will also be taken up by the capsids, whereas the free protein is not incorporated. We further compared this gentle biological method of DNA transfection with a well-established physical method, electroporation. Electroporation also allows the transfer of DNA as well as protein into cells, although there is no proof that a DNA/protein complex can survive the procedure functionally. Whereas the viability of capsid transfected cells is unaffected (100%), electroporation reduces the viability to 90–95%. On the other hand, the amount of DNA found in the nucleus of electroporated cells is higher than for cells treated with loaded viral capsids. 相似文献
16.
Carroll D. Arnett Joanna S. Fowler Robert R. MacGregor David J. Schlyer Alfred P. Wolf Bengt Långström Christer Halldin 《Journal of neurochemistry》1987,49(2):522-527
The distribution of carbon-11-labeled L-deprenyl, an irreversible inhibitor of monoamine oxidase type B (MAO-B), was determined in the baboon brain by positron emission tomography. The irreversible blood-to-brain transfer constant (influx constant, Ki) was measured using a complete metabolite-corrected arterial plasma concentration curve. This influx constant was used as a measure of functional enzyme activity for sequential determinations of MAO-B recovery following a single high dose of unlabeled l -deprenyl. The half-life for turnover of MAO-B was thus determined to be 30 days. Using appropriate irreversible inhibitors, this procedure should be generally useful for determining enzyme turnover rates in any organ in vivo and can be applied to some human studies as well. 相似文献
17.
Wolfgang Heinemeyer Ilka Buchmann Dave W. Tonge John D. Windass Juliane Alt-Moerbe Elmar W. Weiler Thomas Botz Joachim Schröder 《Molecular & general genetics : MGG》1987,210(1):156-164
Summary
Tzs and ipt are two Ti plasmid genes coding for proteins with isopentenyltransferase (IPT) activity in vitro. We cloned both genes for protein expression in Escherichia coli and in Agrobacterium tumefaciens, and we investigated differences between the two genes by analysing the properties of the proteins in vitro and in vivo. In vitro, extracts with tzs or ipt-coded proteins had high IPT activity, and the enzymes were identical in most properties. The most important difference was detected in vivo: the tzs-encoded protein was very active in cytokinin production, while the ipt protein required overexpression in order to obtain measurable activity in bacteria. In both cases, rans-zeatin was the major product of the gene activity. Formation of this cytokinin requires a hydroxylase function in addition to the IPT reaction. No such activity could be ascribed to tzs or ipt-encoded proteins in vitro or in vivo, but cytokinin hydroxylase activity was detected in cells and extracts of E. coli, regardless of the presence or absence of the cytokinin genes. Based on these results it is proposed that both genes code for a single enzyme activity (isopentenyltransferase), that the genes and proteins are adapted for function either in bacteria (tzs) or in transformed plant cells (ipt), and that in both prokaryotic and eukaryotic cells hydroxylation to trans-zeatin is a function contributed by host enzymes.Abbreviations DMAPP
dimethylallylpyrophosphate
- iP
isopentenyladenine
- iPA
isopentenyladenosine
- iPMP
isopentenyladenosine 5-monophosphate
- IPT
isopentenyltransferase
-
trans-Z
trans-zeatin 相似文献
18.
Quantitative estimates of gibberellin A9 in Norway spruce extracts obtained by gas chromatography-mass spectrometry, radioimmunoassay (RIA_ and bioassay were compared after successive purifications of the extracts. The extracts were assayed in several dilutions with and without the addition of standard gibberellin A9, thus showing the effect of extract components on the response of the assays. Radioimmunoassay produced estimates comparable to gas chromatography-mass spectrometry after one purification step by high-performance liquid chromatography. Extracts purified by polyvinylpyrrolidone-column chromatography and solvent partitioning but not high-performance liquid chromatography resulted in inaccurate RIA estimates. The performance of the RIA could be monitored by logit-log transformations of the standard curve and extract dilution curve and by calculating the slope of the standard addition curve. It was, however, not possible to correct for the interference caused by extract components by the standard addition procedure. Quantifications by Tan-ginbozu dwarf-rice bioassay were accurate, but a large and unpredictable variation makes it unsuitable for quantitative determinations.Abbreviations FW
fresh weight
- GA9
gibberellin A9
- GA9–Me
methylated GA9
- GC-MS
gas chromatography-mass spectrometry
- HPLC
high performance liquid chromatography
- MID
multiple-ion detection
- RIA
radioimmunoassay 相似文献
19.
Nina Safar-Hermann Mohammed N. Ismail Han Sun Choi Erich Mstl Elmar Bamberg 《Zoo biology》1987,6(2):189-193
Estrogen concentration in feces was investigated in five different herbivorous species of zoo animals. Using a nonspecific estrogen radioimmunoassay, in four species (red buffalo, yak, Grevy's zebra, and Nubian ibex) pregnancy was revealed by measuring estrogen concentration in feces. In hippopotamus, the levels of fecal estrogens were not different between pregnant and nonpregnant animals. 相似文献
20.
F de Wolf J Goudsmit D A Paul J M Lange C Hooijkaas P Schellekens R A Coutinho J van der Noordaa 《BMJ (Clinical research ed.)》1987,295(6598):569-572
One hundred and ninety eight men seropositive for human immunodeficiency virus (HIV) antibody and 58 HIV antibody seroconverters were studied for an average of 19.3 (SEM 0.5) months to assess the relation between HIV antigenaemia and the risk of developing the acquired immune deficiency syndrome (AIDS) and AIDS related complex. Forty (20.2%) of the 198 HIV antibody seropositive men were antigen positive at entry and remained so during follow up. Eight (13.8%) of the 58 HIV antibody seroconverters and 20 (12.7%) of the remaining 158 HIV antibody seropositive men became antigen positive during follow up, resulting in an end point attack rate for HIV antigenaemia of 14.3%. AIDS related complex was diagnosed in 25 (15.8%) of the HIV antigen negative men and in 14 (20.7%) of the HIV antigen positive men. AIDS was diagnosed in 15 men, resulting in an end point attack rate for AIDS of 23.9% in the HIV antigen positive group and 1.3% in the antigen negative group. HIV antibody seropositive men without symptoms but with persistent HIV antigenaemia are at increased risk of developing AIDS and AIDS related complex. 相似文献