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Biomedical subjects

H Marx

Publications and source records attributed to H Marx.

At least 19 recordsLinked to original sources
PubMed2001

Molecular phylogeny of the genus Kalanchoe (Crassulaceae) inferred from nucleotide sequences of the ITS-1 and ITS-2 regions.

The study presents an analysis of genotypic diversity in the genus Kalanchoe (Crassulaceae) on the level of Internal Transcribed Spacer (ITS) sequences and the attempt to correlate this diversity with previous findings on ecophysiological behavior, habitat preference, infrageneric taxonomic position of the species and DNA polymorphism derived from RAPD-PCR data. The Kalanchoe species are mainly abundant in Madagascar and eastern continental Africa and perform in situ diverse modes of crassulacean acid metabolism (CAM), an ecophysiologically relevant adaptation of photosynthesis. Total DNA was extracted from 68 Kalanchoe species and varieties. The ITS-1 and ITS-2 regions of the nuclear RNA genes were amplified by polymerase chain reaction, cloned and sequenced. The alignments of the sequences were evaluated by distance (neighbor joining) and character state (maximum parsimony) methods. The main topologies of the obtained ITS phylogenetic trees were quite similar irrespective of the mode of evaluation and show: (A) within the Crassulaceae the genus Kalanchoe forms a monophyletic clade; and (B) within the genus the species form three main clusters which coincide well with the previously reported three infrageneric sections of the species distinguishable by classical taxonomic criteria, the mode of in situ CAM performance, and DNA fragment pattern obtained by RAPD-PCR analyses. Moreover, the ITS phylogenetic trees show that all African Kalanchoe species form a distinct group within the most derived of the three main clusters. This is consistent with the view that the center of phylogenetic radiation of the genus is located in Madagascar from where the species have spread into the continental Africa.

Journal Article↗
PubMed2001

A survey of the influence of patients' choice on the increase in the caesarean section rate.

The caesarean section rate in the Royal Gwent Hospital has, as in the rest of the UK, risen significantly over the last 10 years. A commonly proposed reason for this increase is that women themselves are now more likely to request an elective caesarean section, when there is little or no medical indication. The aim of this survey, carried out prospectively, was to find out whether patients' requests for caesarean section are contributing significantly to the rise in the section rate, by attempting to actually quantify the influence of patients' choice on the decision to perform a caesarean section. The results showed that it is possible to quantify this influence, and that maternal request does play a major role in the decision-making process.

Journal Article↗
PubMed1999

[Reference ranges of antioxidant parameters in whole blood (erythrocytes) in a Thüringen region].

BACKGROUND: The oxidant stress is characterized by measurement of the activities of glutathione peroxidase, superoxiddismutase and also by concentrations of glutathione and selenium in erythrocytes. A standardization of the methods of determination is very important. MATERIAL AND METHODS: In erythrocytes of blood donors (n = 101) the parameters glutathione peroxidase, glutathione, superoxiddismutase and selenium were determined. RESULTS: The following results of the antioxidant parameters in erythrocytes of blood donors were found: Selenium 67.1 +/- 20.1 nmol/mmol Hb, glutathione peroxidase 842 +/- 290 U/mmol Hb, glutathione 108 +/- 48 mumol/mmol Hb, superoxiddismutase 15.8 +/- 6.4 U/mumol Hb. CONCLUSION: Selenium, glutathione peroxidase, glutathione and superoxiddismutase in erythrocytes of blood donors are normally distributed. There are no significant differences between men and women. The use of "own reference values" is necessary because no standardization of the methods of determination exists.

Adult↗
PubMed1997

Short- and long-term effects of training phonological awareness in kindergarten: evidence from two German studies.

Two training studies replicated and extended a Scandinavian study by Lundberg, Frost, and Petersen (1988). In Study 1, a 6-month metalinguistic training program was given to kindergartners (mean age: 5 years 7 months) who were later compared to a control group in the regular kindergarten program. Tests of phonological awareness and other metalinguistic and cognitive variables were given before and after training; a metalinguistic transfer test was given after training. Reading and spelling skills were assessed at the end of Grades 1 and 2, respectively. The training program was improved and monitored more closely in Study 2. Both studies revealed short- and long-term effects, consistent with Lundberg et al. (1988) and extending findings from Anglo-American and Scandinavian populations to German children.

Child, Preschool↗
PubMed1995

[Comparative investigations of mycotoxological status of alternatively and conventionally grown crops].

100 samples of rye and 101 samples of wheat coming out of both conventional and alternative or ecological production were investigated for contamination with mycotoxins with interest for our degree of latitude. Deoxynivalenol (DON) was found with thin-layer-chromatography in 131 of 201 samples altogether. A top level of 1250 micrograms DON kg-1 in rye of alternative offspring was detected. The average burden in contaminated rye coming from ecological production was 427 micrograms kg-1 and a mean level of 160 micrograms kg-1 resulting in rye out of conventional growth conditions. In wheat, conventionally grown yield showed slightly lower contamination (mean levels of 420 micrograms DON kg-1 towards 486 micrograms kg-1). The toxins 3-acetyl-deoxynivalenol, nivalenol and fusarenone X were detected in some samples by thin-layer-chromatography. This results could not be confirmed by gas chromatography -mass spectrometry. Zearalenone was found in 40 out of the number of 201 samples of grain by HPLC with fluorescence detection. An average of 6 micrograms and 24 micrograms zearalenone kg-1 in conventionally and alternatively grown wheat and 4 micrograms and 51 micrograms zearalenone kg-1 in conventionally and alternatively produced rye was detected. The highest finding of zearalenone was 199 micrograms kg-1 in alternatively grown rye. Skin toxicity testing did not show any reference of contamination with type-A-trichothecenes. No correlation between contamination of zearalenone or deoxynivalenol and thousand-kernel-weight was detected.

Agriculture↗
PubMed1995

[Evaluation of the meat quality of game].

The carcasses of 140 roe deer, 129 wild boars, 81 red deer and 55 fallow deer were examined to determine meat quality with respect to the influence of typical hunting situations. After hunting, many carcasses had not been cooled, which significantly influenced meat-quality parameters. The pH-value, detected electrochemically, gave the most reliable results out of all the meat-quality parameters investigated. Determination of the pH-value with regard to the pH indexes ascertained for different points of measurement and types of game is helpful in properly judging the substantial quality of venison. Determination of electrical conductivity and water-holding capacity (Q) can be helpful in judging meat quality. The value of residual-blood content in judging substantial venison quality is, however, doubtful. The measurement of rapid glycolysis and the evaluation of rigor mortis are not appropriate for determining the substantial quality of venison.

Animals↗
PubMed1994

[Comparative studies of the bacterial and mycological status of ecologically and conventionally grown crops].

Wheat and rye derived from conventional and from alternative or ecological production was examined for bacterial and fungal contamination. The overall bacterial and fungal contamination was lower than 10(7.7) germs/g. The amount and type of germs in the grain corresponded to typical contamination of fresh crop. No difference in germ contamination of both conventionally and alternatively grown wheat and rye could be found. No correlation between bacterial or fungal contamination and thousand-kernel-weight was detected.

Agriculture↗
PubMed1991

[Dependence of correct solution of phonetic information on the number and kind of picture information].

It was to be shown that kindergarten children do not synthesize phonologically, auditorily presented sound sequences but solve the task primarily in a picture-related manner by using visual information and selecting singular sound units or elements. The first study demonstrated that the picture material rather than the concrete sound sequence determines the extent of correct solution. In addition, the solutions are influenced by the kind of phonetic relationship among the picture information rather than by the introduction of picture distractors. These results were basically replicated in the second study. The results are discussed against the background of decision making that is mainly oriented to the situative cues of the task and only secondarily to the sound aspects.

Child↗