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1. Generation of a transmembrane electric potential difference by oligomycin-sensitive ATPase complex, incorporated into spherical or planar phospholipid membrane, has been demonstrated. To this end, penetrating anion probe and direct voltmeter measurement of electric potential across phospholipid membrane were used. It was found that ATP-induced electric response is sensitive to oligomycin and protonophorous uncouplers. 2. The effect of variations in the phospholipid component of proteoliposomes on the electric generation was studied. It was revealed that the usage of mitochondrial phospholipids and phosphatidylethanolamine allows the highest values of membrane potential to be obtained in the case of ATPase proteoliposomes. In the case of cytochrome oxidase and bacteriorhodopsin proteoliposomes, phosphatidylserine was also shown to be quite suitable. Phosphatidylcholine was absolutely ineffective in all cases. 3. In proteoliposomes, containing both ATPase and bacteriorhodopsin, ATP and light induced generation of the electric field of the same direction. 4. In ATPase + cytochrome oxidase proteoliposomes, ATP hydrolysis and ascorbate oxidation was found to support electric generation of the same direction if cytochrome c was inside vesicles. Oxidation via external cytochrome c resulted in formation of electric field of the direction, opposite to that induced by ATP hydrolysis. 5. The data obtained in experiments with proteoliposomes of different types are discussed. The conclusion is made that conversion of energy of different resources into electric form is a common feature of membraneous energy transducers, which is in agreement with the Mitchellian principle of cellular energetics.  相似文献   
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Clinal patterns of autosomal genetic diversity within Europe have been interpreted in previous studies in terms of a Neolithic demic diffusion model for the spread of agriculture; in contrast, studies using mtDNA have traced many founding lineages to the Paleolithic and have not shown strongly clinal variation. We have used 11 human Y-chromosomal biallelic polymorphisms, defining 10 haplogroups, to analyze a sample of 3,616 Y chromosomes belonging to 47 European and circum-European populations. Patterns of geographic differentiation are highly nonrandom, and, when they are assessed using spatial autocorrelation analysis, they show significant clines for five of six haplogroups analyzed. Clines for two haplogroups, representing 45% of the chromosomes, are continentwide and consistent with the demic diffusion hypothesis. Clines for three other haplogroups each have different foci and are more regionally restricted and are likely to reflect distinct population movements, including one from north of the Black Sea. Principal-components analysis suggests that populations are related primarily on the basis of geography, rather than on the basis of linguistic affinity. This is confirmed in Mantel tests, which show a strong and highly significant partial correlation between genetics and geography but a low, nonsignificant partial correlation between genetics and language. Genetic-barrier analysis also indicates the primacy of geography in the shaping of patterns of variation. These patterns retain a strong signal of expansion from the Near East but also suggest that the demographic history of Europe has been complex and influenced by other major population movements, as well as by linguistic and geographic heterogeneities and the effects of drift.  相似文献   
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Background  

The aim of the study was to detect whether in experimental Salmonella enterica Typhimurium infection the probiotic Lactobacillus fermentum ME-3 in combination with fluoroquinolone therapy would eradicate S. Typhimurium, prevent the development of liver and spleen granulomas and improve the indices of oxidative stress in the ileum mucosa.  相似文献   
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Summary In the article the results of a parallel routine and fluorescent investigation of chromosomes in 103 normal individuals (51 women and 52 men) are presented. There were no gross chromosomal abnormalities in the individuals studied, but in 30 (29.1%) of them various autosomal variants (1q+, 9q+, 16q+, 17ph+, Dp+, Gp+, et al.) were detected by the routine method. Five men (9.5%) had Y chromosome variants. The authors were successful in identifyng practically all these chromosomal variant by their fluorescent banding patterns. The occurrence of brilliant fluorescent bands in chromosome parts showing variable fluorescence (paracentromeric area of chromosome 3, short arms and satellites of acrocentric chromosomes and the distal part of Y chromosome) was also investigated. Some questions connected with karyotype polymorphism in man are discussed.
Zusammenfassung Die Ergebnisse einer Chromosomenuntersuchung mit konventionellen Methoden einerseits und mit der Fluorescenzmethode andererseits bei 103 Normalpersonen (51 Frauen, 52 M?nner) werden vorgelegt. Die untersuchten Personen zeigten keine st?rkeren Chromosomen-Anomalien; 30 (29,1%) zeigten jedoch verschiedene autosomale Varianten (1q+, 9q+, 16q+, 17ph+, Dp+, Gp+, u.a.), die mit konventionellen Methoden entdeckt werden konnten. Fünf M?nner (9,5%) zeigten Varianten des Y-Chromosoms. Praktisch alle diese Varianten konnten auch mit Hilfe der Fluorescenztechnik identifiziert werden. Daneben wurde das Vorkommen brillanter Fluorescenzbanden in Chromosomen, die eine variable Fluorescenz zeigen, untersucht (parazentrischer Bereich des Chromosoms 3; kurze Arme und Satelliten der akrozentrischen Chromosomen; distaler Teil des Y-Chromosoms 3; kurze Arme und Satelliten der akrozentrischen Chromosomen; distaler Teil des Y-Chromosoms). Einige Fragen im Zusammenhang mit dem Polymorphismus des Karyotyps beim Menschen werden diskutiert.


This investigation is partly supported by the WHO grant HG-70/9684148/23.  相似文献   
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The aim of this study was to screen intestinal lactobacilli strains for their advantageous properties to select those that could be used for the development of novel gastrointestinal probiotics. Ninety-three isolates were subjected to screening procedures. Fifty-nine percent of the examined lactobacilli showed the ability to auto-aggregate, 97% tolerated a high concentration of bile (2% w/v), 50% survived for 4 h at pH 3.0, and all strains were unaffected by a high concentration of pancreatin (0.5% w/v). One Lactobacillus buchneri strain was resistant to tetracycline. None of the tested strains caused lysis of human erythrocytes. Six potential probiotic strains were selected for safety evaluation in a mouse model. Five of 6 strains caused no translocation, and were considered safe. In conclusion, several strains belonging to different species and fermentation groups were found that have properties required for a potential probiotic strain. This study was the first phase of a multi-phase study aimed to develop a novel, safe and efficient prophylactic and therapeutic treatment system against gastrointestinal infections using genetically modified probiotic lactobacilli.  相似文献   
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Summary Ag-staining of the nucleolus organizer region (NOR) was studied in the acrocentric chromosomes identified by Q-banding in repeated lymphocyte and skin fibroblast cultures from three different individuals. A similar pattern of Ag-stainability of NORs was found in the two tissues in each individual. Small differences concerning, in each case, only one of the acrocentric chromosomes were found between repeated lymphocyte cultures, as well as between lymphocyte and fibroblast cultures of the same individual without indication of any prevalence of one tissue type in a certain direction. The possibility that these differences are caused by different stages of NOR activation is discussed.  相似文献   
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We analyzed 10 Y-chromosomal binary markers in 363 males from 8 populations in Northern Europe and 5 Y microsatellites in 346 of these individuals. These populations can be grouped according to cultural, linguistic, or geographical criteria, and the groupings are different in each case. We can therefore ask which criterion best corresponds to the distribution of genetic variation. In an AMOVA analysis using the binary markers, 13% of the Y variation was found between populations, indicating a high level of differentiation within this small area. No significant difference was seen between the traditionally nomadic Saami and the neighboring, historically farming, populations. When the populations were divided into Uralic speakers and Indo-European speakers, 8% of the variation was found between groups, but when they were divided according to geographical location, 14% of the variation was between groups. Geographical factors have thus been the most important in limiting gene flow between these populations, but linguistic differences have also been important in the east.  相似文献   
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