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Kai Korpela Matti Laaksonen Arja Kallio Hans Söderlund Ulf Pettersson Hannu Kyrönseppä Marjut Ranki 《FEMS microbiology letters》1992,90(2):173-178
A rapid DNA-test, depending on the affinity based hybrid collection principle, was developed for the detection of Plasmodium falciparum DNA from clinical specimens. In this method, hybridization takes place in solution and the hybrids are collected onto a solid phase for measurement. Two probes are used, one labelled with an affinity tag (biotin) and the other with a detectable label (32P). In the present test a single oligonucleotide complementary to a 21-base pair sequence which is highly repeated in the parasite genome served both as capture and detector probe. The test is a 2-h hybridization performed in streptavidin coated microtitration plate wells, onto which the labelled hybrids simultaneously bind. The sensitivity of the assay with a crude erythrocyte lysate specimen was 1.6 x 10(9) repeat units corresponding to about 160 parasites in one microliter blood. The results allowed quantification of the repeat sequences and thus estimation of the degree of parasitemia in clinical specimens. 相似文献
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We have investigated the local and regional scale genetic structure of Siberian primrose (Primula nutans) populations in Northern Europe. The genetic diversity and structure of fifteen populations sampled from the Bothnian Bay
in Finland, the Barents Sea in Norway and the White Sea in Russia were assessed using eleven microsatellite markers. We investigated
the distribution of genetic variation within and between populations, and studied the local genetic structure using spatial
autocorrelation analysis. We found very low genetic and allelic diversity in the Bothnian Bay and Barents Sea populations,
and only slightly higher in the White Sea population. The level of genetic differentiation between the regions was very high,
whereas differentiation between the populations within the regions was moderate. We found no spatial structuring of populations
in any region suggesting efficient dispersal on a local scale. Clonal reproduction seemed to have no effect on genetic structure. 相似文献
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Eila Torvinen Teija Meklin Pirjo Torkko Sini Suomalainen Marjut Reiman Marja-Leena Katila Lars Paulin Aino Nevalainen 《Applied microbiology》2006,72(10):6822-6824
In contrast to the growth of fungi, the growth of mycobacteria in moisture-damaged building materials has rarely been studied. Environmental mycobacteria were isolated from 23% of samples of moisture-damaged materials (n = 88). The occurrence of mycobacteria increased with increasing concentrations of fungi. Mycobacteria may contribute to indoor exposure and associated adverse health effects. 相似文献
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In the Baltic Sea, herring (Clupea harengus membras) spawns in the littoral zone, where its eggs are attached to algae or vascular plants. Field studies indicate that egg mortality
can be very high (up to 100%) in eggs that are attached to red algae (Rajasilta et al., 1989, 1993). Because high mortality can be due to allelochemical effects of the algae, we studied the mortality of herring eggs on different
algal substrates experimentally. Four types of substrates were tested: fresh Cladophora and Furcellaria, and Furcellaria that had decomposed six days or 23 days. The incubation time in the experiments was 3 days and incubation temperature 12–13 oC (ca. 700–800 h-degrees). The results were in accordance with observations made in field studies and indicated significant
differences among the substrate types. In eggs attached to fresh Cladophora, mortality was significantly lower (mean=2.8%; n=20) than in those attached to Furcellaria, independently of the treatment of the algae. The highest values of mortality (mean=14.4%; n=20) were found in eggs attached to Furcellaria that had decomposed over a six days’ period. This suggested that Furcellaria contain some chemical substances, which can cause mortality in herring embryos and the effect seems to be dependent on the
state of decomposition of the algae. 相似文献
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Behm Katri Nappa Marja Aro Nina Welman Alan Ledgard Stewart Suomalainen Marjut Hill Jeremy 《The International Journal of Life Cycle Assessment》2022,27(8):1017-1034
The International Journal of Life Cycle Assessment - This paper studies the carbon footprint and water scarcity footprint (WSF) of a milk protein, beta-lactoglobulin, produced by cellular... 相似文献
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Nieminen SM Mäki-Paakkanen J Hirvonen MR Roponen M von Wright A 《Mutation research》2002,520(1-2):161-170
The genotoxic effects of gliotoxin, a known fungal secondary metabolite, were studied. Gliotoxin was purified from cultivation medium of Aspergillus fumigatus isolated from the indoor air of a moisture problem house. The genotoxicity of gliotoxin was assessed both in bacterial test systems including bacterial repair assay, Ames Salmonella assay and SOS-chromotest, and in mammalian cells using single cell gel (SCG) electrophoresis assay and sister-chromatid exchange (SCE) test. Gliotoxin was found to be genotoxic in the bacterial repair assay but, not in the Salmonella test or SOS-chromotest. A dose-related increase in DNA damage was observed in mouse RAW264.7 macrophages exposed to gliotoxin for 2h in plain medium in the SCG assay. In contrast to the positive response in the SCG assay, gliotoxin did not induce any clear, dose-related increase in SCEs in Chinese hamster ovary (CHO) cells. 相似文献
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Otala M Pentikäinen MO Matikainen T Suomalainen L Hakala JK Perez GI Tenhunen M Erkkilä K Kovanen P Parvinen M Dunkel L 《Biology of reproduction》2005,72(1):86-96
Deficiency of acid sphingomyelinase (ASM), an enzyme responsible for producing a pro-apoptotic second messenger ceramide, has previously been shown to promote the survival of fetal mouse oocytes in vivo and to protect oocytes from chemotherapy-induced apoptosis in vitro. Here we investigated the effects of ASM deficiency on testicular germ cell development and on the ability of germ cells to undergo apoptosis. At the age of 20 weeks, ASM knock-out (ASMKO) sperm concentrations were comparable with wild-type (WT) sperm concentrations, whereas sperm motility was seriously affected. ASMKO testes contained significantly elevated levels of sphingomyelin at the age of 8 weeks as detected by high-performance, thin-layer chromatography. Electron microscopy revealed that the testes started to accumulate pathological vesicles in Sertoli cells and in the interstitium at the age of 21 days. Irradiation of WT and ASMKO mice did not elevate intratesticular ceramide levels at 16 h after irradiation. In situ end labeling of apoptotic cells also showed a similar degree of cell death in both groups. After a 21-day recovery period, the numbers of primary spermatocytes and spermatogonia at G2 as well as spermatids were essentially the same in the WT and ASMKO testes, as detected by flow cytometry. In serum-free cultures both ASMKO and WT germ cells showed a significant increase in the level of ceramide, as well as massive apoptosis. In conclusion, ASM is required for maintenance of normal sphingomyelin levels in the testis and for normal sperm motility, but not for testicular ceramide production or for the ability of the germ cells to undergo apoptosis. 相似文献
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Krohn K Stanescu I Blazevic V Vesikari T Ranki A Ustav M 《Microbes and infection / Institut Pasteur》2005,7(14):1405-1413
A potent DNA vaccine against HIV, combining a vector that takes advantage of the segregation and compartmentalization effect of bovine papilloma virus E2 protein with MultiHIV insert, expressing a fusion gene coding for the non-structural and structural proteins was developed and tested for immunogenicity in mice and humans. 相似文献