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The nematode Angiostrongylus cantonensis is the causative agent of human angiostrongyliasis, the main clinical manifestation of which is eosinophilic meningitis. Although this parasite has been found recently in its definitive rat host in Tenerife (Canary Islands, Spain), showing a widespread distribution over the north-east part of the island, there are no available data regarding which snail and/or slug species are acting as intermediate hosts on this island. Consequently, the objective of this work was to determine the possible role of three mollusc species, Plutonia lamarckii, Cornu aspersum and Theba pisana, as intermediate hosts of A. cantonensis in Tenerife. Between 2011 and 2014, 233 molluscs were collected from five biotopes where rats had been found previously to harbor either adult worms or antibodies against A. cantonensis, and the identification was carried out on the basis of morphological features and a LAMP technique. The prevalence of A. cantonensis larvae in the mollusc samples, based on morphological identification, was 19.3%, whereas 59 out of the 98 individuals (60.2%) analyzed by LAMP were positive. Positive results were obtained for the three mollusc species analyzed and two of the positive samples, both obtained from P. lamarckii, were confirmed as positive by 18S rRNA and ITS1 PCR. Sequence analysis of 18S rRNA PCR products showed 100% similarity with previously published A. cantonensis sequences. These results may be relevant from a public health point of view, since all the biotopes from which the samples were obtained were in inhabited areas or areas with human activity, but it is also important from the perspective of a possible transmission to other accidental hosts, such as dogs and horses, animals that are present in some of the areas analyzed.  相似文献   
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Acanthamoeba keratitis cases have emerged in the recent years in Iran. In this case, an amoebic keratitis due to a mixed infection with Acanthamoeba and Vahlkampfia species is reported. Corneal scrapes, contact lenses and contact lens cases obtained from the patient were analysed and were positive for cysts of Acanthamoeba and Vahlkampfia genera. Genus-specific PCR was carried out for both genera, confirming the microscopic observations. To our knowledge, this is the first reported case of a possible mixed amoebic infection due to Acanthamoeba and Vahlkampfia and raises awareness within contact lens wearers in Iran.  相似文献   
96.

Background  

The WHO considers leishmaniasis as one of the six most important tropical diseases worldwide. It is caused by parasites of the genus Leishmania that are passed on to humans and animals by the phlebotomine sandfly. Despite all of the research, there is still a lack of understanding on the metabolism of the parasite and the progression of the disease. In this study, a mathematical model of disease progression was developed based on experimental data of clinical symptoms, immunological responses, and parasite load for Leishmania amazonensis in BALB/c mice.  相似文献   
97.
Cell migration/proliferation processes associated with wound healing were measured in BeWo cells at 6 h, when mitosis is still scarce. Cells were cultured in medium with 1% fetal bovine serum to minimize proliferation. BeWo cell migration covered 20.6 ± 7.0%, 38.0 ± 5.4%, 16.6 ± 4.8% and 13.7 ± 3.6% of the wound when cultivated under control, aldosterone (100 nM, 12 h), aldosterone plus amiloride (10 μM) and amiloride treatments, respectively. When BeWo cells were treated with aldosterone, there was an increase in wound healing (P < 0.05), which was prevented by adding the ENaC blocker amiloride (P < 0.05, n = 16). Immunocytochemistry studies showed that the three ENaC subunits showed greater expression at the leading edge of the wound 3 h after injury, supporting the notion that these proteins participate in a postinjury signal. Antisense oligonucleotides directed against the α-ENaC subunit decreased the migratory response of the cells compared to the sense treated cells or the cells without oligonucleotides (P < 0.001, n = 16): 30.2 ± 3.7%, 17.6 ± 1.3%, 27.5 ± 1.5% and 20.2 ± 1.5% reinvasion of the wound with aldosterone, aldosterone plus antisense, aldosterone plus sense treatments and control conditions, respectively. Aldosterone and amiloride influence wound healing in BeWo cells, probably by their effects upon ENaCs, transmitting a signal to the cell cytoplasm for the release of several agents that promote cell migration.  相似文献   
98.
A total of 109 sea urchins from 3 species collected in 2 localities off the coast of Tenerife Island, Spain, were examined for the presence of free-living amoebae in their coelomic fluid. Amoeba trophozoites were isolated exclusively from moribund individuals of long-spined sea urchins Diadema aff. antillarum (Philippi) (Echinoidea, Echinodermata) that manifested lesions related to sea urchin bald disease on their tests (16 out of 56 examined). No amoebae were detected in Arbacia lixula (L.) and Paracentrotus lividus (Lamarck). From the former sea urchin species, 8 strains, established from 10 primary isolates, were identified as Neoparamoeba branchiphila Dyková et al., 2005 using morphological and molecular methods. Results of this study (limited to the screening for free-living amoebae) together with data on agents of sea urchin mortalities reported to date justify the hypothesis that free-living amoebae play an opportunistic role in D. aff. antillarum mortality. The enlargement of the dataset of SSU rDNA sequences brought new insight into the phylogeny of Neoparamoeba species.  相似文献   
99.
Lake Tovel, an oligotrophic mountain lake (Trentino, N. Italy) is famous for its past bright red summer blooms of the dinoflagellate Glenodinium sanguineum Marchesoni. In 1938 and 1941 Baldi studied the lake and bloom phenomenon in detail. In particular, he found that the dinoflagellate showed high morphological plasticity and that it was present in the whole lake, but concentrated in the Red Bay, where it exhibited an active vertical migration. In 2001 the presence of G. sanguineum in the whole lake, with higher densities in the Red Bay could be confirmed. However the cell densities found in the Red Bay are up to 103 lower than those reported by Baldi. During two diurnal studies in August 2001 almost identical diurnal depth variations of maximum density of G. sanguineum were found, likely to be related to positive phototaxis. Although in the Red Bay the patterns of vertical variations were less clear, potential influential factors (wind, sun, temperature) are analysed and discussed. Dinoflagellate species composition from this and earlier studies show an increase in the number of taxa recorded from the lake in recent years and a shift in species composition possibly related to changes in the trophic status of the lake.  相似文献   
100.
The nitrogen cycle (N-cycle), principally supported by prokaryotes, involves different redox reactions mainly focused on assimilatory purposes or respiratory processes for energy conservation. As the N-cycle has important environmental implications, this biogeochemical cycle has become a major research topic during the last few years. However, although N-cycle metabolic pathways have been studied extensively in Bacteria or Eukarya, relatively little is known in the Archaea. Halophilic Archaea are the predominant microorganisms in hot and hypersaline environments such as salted lakes, hot springs or salted ponds. Consequently, the denitrifying haloarchaea that sustain the nitrogen cycle under these conditions have emerged as an important target for research aimed at understanding microbial life in these extreme environments. The haloarchaeon Haloferax mediterranei was isolated 20 years ago from Santa Pola salted ponds (Alicante, Spain). It was described as a denitrifier and it is also able to grow using NO3 -, NO2 - or NH4 + as inorganic nitrogen sources. This review summarizes the advances that have been made in understanding the N-cycle in halophilic archaea using Hfx mediterranei as a haloarchaeal model. The results obtained show that this microorganism could be very attractive for bioremediation applications in those areas where high salt, nitrate and nitrite concentrations are found in ground waters and soils.  相似文献   
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