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1.
Summary The frequency of the occurrence of the Rh(D)-factor was compared in 1185 first-born babies with that among 2246 children from 2nd and later pregnancies. Among the first-born children 14,2% were Rh(D)-negative, and among the later-born 14,7% were Rh(D)-negative. In children with the Blood group O the distribution of the Rh(D) bloodgroup was the same in both first-born and later-born children. Among the Rh(D)-positive children there seem to be less boys.  相似文献   
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Summary Homocysteine (HC) is a radiation protector but toxic to bone. Its derivative homocysteine thiolactone (HCTL) and the alpha-alkylated analogue (A-methyl-HCTL) was fed to mice for a period of six weeks in a daily dose of 50 mg/kg body weight. Parameters for bone matrix as collagen content, acid solubility of bone collagen, urinary bone collagen cross links (pyridinolines) and urinary acid glycosaminoglycans were determined. Urinary acid glycosaminoglycans were significantly reduced in the HCTL treated group but not in the alpha-methyl-homocysteine thiolactone (A-methyl-HCTL) group (controls: 45 ± 7 mg/mmol creatinine, homocysteine thiolactone 38 ± 5 mg/mmol creatinine, A-methyl HCTL 45 ± 6 mg/mmol creatinine).No differences were found for the parameters of bone collagen between the groups. The potent radiation protecting methylated derivative therefore did not change bone matrix and should be a candidate for further toxicological studies.  相似文献   
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It needs three factors to build an industry: market demand, product vision and capital. White biotechnology already produces high volume products such as feed additive amino acids and specialty products like enzymes for enantioselective biocatalysis. It serves large and diverse markets in the nutrition, wellness, pharmaceutical, agricultural and chemical industry. The total volume adds up to $ 50 billion worldwide. In spite of its proven track record, white biotechnology so far did not attract as much capital as red and even green biotechnology. However, the latest finance indicators confirm the continuously growing attractiveness of investment opportunities in white biotechnology. This article discusses white biotechnology's position and potential in the finance market and success factors.  相似文献   
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Imitation of facial expressions engages the putative human mirror neuron system as well as the insula and the amygdala as part of the limbic system. The specific function of the latter two regions during emotional actions is still under debate. The current study investigated brain responses during imitation of positive in comparison to non-emotional facial expressions. Differences in brain activation of the amygdala and insula were additionally examined during observation and execution of facial expressions. Participants imitated, executed and observed happy and non-emotional facial expressions, as well as neutral faces. During imitation, higher right hemispheric activation emerged in the happy compared to the non-emotional condition in the right anterior insula and the right amygdala, in addition to the pre-supplementary motor area, middle temporal gyrus and the inferior frontal gyrus. Region-of-interest analyses revealed that the right insula was more strongly recruited by (i) imitation and execution than by observation of facial expressions, that (ii) the insula was significantly stronger activated by happy than by non-emotional facial expressions during observation and imitation and that (iii) the activation differences in the right amygdala between happy and non-emotional facial expressions were increased during imitation and execution, in comparison to sole observation. We suggest that the insula and the amygdala contribute specifically to the happy emotional connotation of the facial expressions depending on the task. The pattern of the insula activity might reflect increased bodily awareness during active execution compared to passive observation and during visual processing of the happy compared to non-emotional facial expressions. The activation specific for the happy facial expression of the amygdala during motor tasks, but not in the observation condition, might reflect increased autonomic activity or feedback from facial muscles to the amygdala.  相似文献   
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The determination of protein-protein interactions is becoming more and more important in the molecular analysis of signal transduction chains. To this purpose the application of a manageable and simple assay in an appropriate biological system is of major concern. Bimolecular fluorescence complementation (BiFC) is a novel method to analyze protein-protein interactions in vivo. The assay is based on the observation that N- and C-terminal subfragments of the yellow-fluorescent protein (YFP) can only reconstitute a functional fluorophore when they are brought into tight contact. Thus, proteins can be fused to the YFP subfragments and the interaction of the fusion proteins can be monitored by epifluorescence microscopy. Pairs of interacting proteins were tested after transient cotransfection in etiolated mustard seedlings, which is a well characterized plant model system for light signal transduction. BiFC could be demonstrated with the F-box protein EID1 (empfindlicher im dunkelroten Licht 1) and the Arabidopsis S-phase kinase-related protein 1 (ASK1). The interaction of both proteins was specific and strictly dependent on the presence of an intact F-box domain. Our studies also demonstrate that etiolated mustard seedlings provide a versatile transient assay system to study light-induced subcellular localization events.  相似文献   
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Zusammenfassung In der Annahme, daß Blutgruppeninkompatibilität sich häufig erst nach Immunisierung der Mutter durch eine vorausgegangene Schwangerschaft für die nachfolgenden Kinder deletär auswirken dürfte, kamen wir zu der Vermutung, daß die der Selektion verfallenen Blutgruppen bei nachgeborenen Kindern seltener angetroffen werden müßten als bei Erstgeburten, während vor allem die Blutgruppe O eher vermehrt zu finden wäre. Wir haben daher die Blutgruppen-verteiling bei 1186 estgeborenen derjenigen von 2112 nachgeborenen Kindern gegenübergestellt. Es zeigt sich, daß die Blutgruppe O bei den weiteren Kindern häufiger vorkommt als bei den erstgeborenen, die Blutgruppen B and AB dagegen seltener. Ein vermehrter Ausfall von Knabengeburten als Folge der größeren Anfälligkeit des männlichen Geschlechtes scheint nach unseren Ermittlungen nur für Erstgeburten zuzutreffen. Gleichartige Veränderungen der Häufigkeitsverteilung Rh-positiver Individuen scheinen in viel geringerem Ausmaße vorzukommen.
The ABO blood group distribution was compared in 1186 first born and 2112 later born children. Among the later born children group 0 is significantly more frequent, whereas groups B and AB are rarer. Additionally, the number of firstborn males seems to be reduced due to selection. The influence of selection by incompatibility seems to be smaller in the Rh than in the ABO system.


Ärztl. Leiter: Prim. Dr. W. Kircher  相似文献   
9.
Differentiation of naïve CD4+ T cells into effector subtypes with distinct cytokine profiles and physiological roles is a tightly regulated process, the imbalance of which can lead to an inadequate immune response or autoimmune disease. The crucial role of Ca2+ signals, mainly mediated by the store operated Ca2+ entry (SOCE) in shaping the immune response is well described. However, it is unclear if human effector CD4+ T cell subsets show differential Ca2+ signatures in response to different stimulation methods. Herein, we provide optimized in vitro culture conditions for polarization of human CD4+ effector T cells and characterize their SOCE following both pharmacological store depletion and direct T-cell receptor (TCR) activation. Moreover, we measured whole cell Ca2+ release activated Ca2+ currents (ICRAC) and investigated whether the observed differences correlate to the expression of CRAC genes. Our results show that Ca2+ profiles of helper CD4+ Th1, Th2 and Th17 are distinct and in part shaped by the intensity of stimulation. Regulatory T cells (Treg) are unique being the subtype with the most prominent SOCE response. Analysis of in vivo differentiated Treg unraveled the role of differential expression of ORAI2 in fine-tuning signals in Treg vs. conventional CD4+ T cells.  相似文献   
10.
The sterol diol fraction from the lipids of organ-pipe cactus, Stenocereus thurberi, was separated into five compounds: macdougallin, peniocerol, cyclostenol, stenocereol and thurberol. The last three compounds have not been described before. All compounds were characterized by physical and spectroscopic properties.  相似文献   
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