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1.
The purpose of the present study was to investigate possible methods to enhance the rate of biodegradation of oil sludge from crude oil tank bottom, thus reducing the time usually required for bioremediation. Enhancement of biodegradation was achieved through bioaugmentation and biostimulation. About 10% and 20% sludge contaminated sterile and non-sterile soil samples were treated with bacterial consortium (BC), rhamnolipid biosurfactant (RL) and nitrogen, phosphorus and potassium (NPK) solution. Maximum n-alkane degradation occurred in the 10% sludge contaminated soil samples. The effects of treatment carried out with the non-sterile soil samples were more pronounced than in the sterile soils. Maximum degradation was achieved after the 56th day of treatment. n-Alkanes in the range of nC8-nC11 were degraded completely followed by nC12-nC21, nC22-nC31 and nC32-nC40 with percentage degradations of 100%, 83-98%, 80-85% and 57-73% respectively. Statistical analysis using analysis of variance and Duncan's multiple range test revealed that the level of amendments, incubation time and combination of amendments significantly influenced bacterial growth, protein concentration and surface tension at a 1% probability level. All tested additives BC, NPK and RL had significant positive effects on the bioremediation of n-alkane in petroleum sludge.  相似文献   
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Use of spectral analysis to test hypotheses on the origin of pinnipeds   总被引:10,自引:4,他引:6  
The evolutionary origin of the pinnipeds (seals, sea lions, and walruses) is still uncertain. Most authors support a hypothesis of a monophyletic origin of the pinnipeds from a caniform carnivore. A minority view suggests a diphyletic origin with true seals being related to the mustelids (otters and ferrets). The phylogenetic relationships of the walrus to other pinniped and carnivore families are also still particularly problematic. Here we examined the relative support for mono- and diphyletic hypotheses using DNA sequence data from the mitochondrial small subunit (12S) rRNA and cytochrome b genes. We first analyzed a small group of taxa representing the three pinniped families (Phocidae, Otariidae, and Odobenidae) and caniform carnivore families thought to be related to them. We inferred phylogenetic reconstructions from DNA sequence data using standard parsimony and neighbor-joining algorithms for phylogenetic inference as well as a new method called spectral analysis (Hendy and Penny) in which phylogenetic information is displayed independently of any selected tree. We identified and compensated for potential sources of error known to lead to selection of incorrect phylogenetic trees. These include sampling error, unequal evolutionary rates on lineages, unequal nucleotide composition among lineages, unequal rates of change at different sites, and inappropriate tree selection criteria. To correct for these errors, we performed additional transformations of the observed substitution patterns in the sequence data, applied more stringent structural constraints to the analyses, and included several additional taxa to help resolve long, unbranched lineages in the tree. We find that there is strong support for a monophyletic origin of the pinnipeds from within the caniform carnivores, close to the bear/raccoon/panda radiation. Evidence for a diphyletic origin was very weak and can be partially attributed to unequal nucleotide compositions among the taxa analyzed. Subsequently, there is slightly more evidence for grouping the walrus with the eared seals versus the true seals. A more conservative interpretation, however, is that the walrus is an early, but not the first, independent divergence from the common pinniped ancestor.   相似文献   
4.
A commercial culture of Kefir grew well at 30°C and 37°C with NaCl up to 4% (w/v) but at 42°C and 4% (w/v) NaCl it grew very slowly. These conditions were selected for the mutation with N-methyl-N-nitrosoguanidine in order to improve cell yield at high temperatures and salt concentration. The mutated cells had higher biomass and growth rate compared with the original culture. The improvement of Kefir at high temperatures and salt concentrations offers advantages for uses in single cell protein production and alcohol production from whey containing high salt.  相似文献   
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Phlomis fruticosa is one of the main species of post-fire Mediterranean communities, occupying areas with post-fire grazing or altered precipitation pattern and consequently water stress imposed on seedlings of co-occurring species. Seedlings of woody perennials often differ from their mature individuals regarding their resistance of photosynthetic performance to environmental stresses. Such differences have been reported for tree species but there is a lack of information regarding shrub species. In the present study, we tried to detect changes in (PSII) activity imposed by water stress in P. fruticosa seedlings as well as its capability for recovery after rehydration. Maximum PSII photochemical efficiency decreased only under severe water stress exactly as in mature plants in the field. However, leaf chlorophyll (Chl) content was almost stable regardless of leaf relative water content (RWC). We assume that the photoprotective chlorophyll loss process, reported for many mature Mediterranean species (including P. fruticosa), has not yet been developed at the seedling stage. On the other hand, photoprotection through an increase of the relative amount of non-QB-reducing centers was found during dehydration. Non-photochemical quenching (NPQ) contributed to protection from photodamage until moderate water stress but was significantly suppressed under severe water stress. Both processes were reversed after rehydration. The above characteristics enabled seedlings not only to survive during aggravating drought but also to maintain a considerable part of their effective quantum yield and perform significant electron transport even at extremely low relative water content (RWC). This was confirmed with measurements in a semi-natural environment (pots) and under real steady state conditions regarding adaptation of the photosynthetic machinery to prevailing light intensities.  相似文献   
7.

Objectives

Examination of sensorimotor activation alone in multiple sclerosis (MS) patients may not yield a comprehensive view of cerebral response to task stimulation. Additional information may be obtained by examining the negative BOLD response (deactivation). Aim of this work was to characterize activation and deactivation patterns during passive hand movements in MS patients.

Methods

13 relapsing remitting-MS patients (RRMS), 18 secondary progressive-MS patients (SPMS) and 15 healthy controls (HC) underwent an fMRI study during passive right-hand movements. Activation and deactivation contrasts in the three groups were entered into ANOVA, age and gender corrected. Post-hoc analysis was performed with one-sample and two-sample t-tests. For each patient we obtained lesion volume (LV) from both T1- and T2-weighted images.

Results

Activations showed a progressive extension to the ipsilateral brain hemisphere according to the group and the clinical form (HC<RRMS<SPMS). Significant deactivation of the ipsilateral cortical sensorimotor areas was reduced in both patient groups with respect to HC. Deactivation of posterior cortical areas belonging to the default mode network (DMN), was increased in RRMS, but not in SPMS, with respect to HC. The amount of activation in the contralateral sensorimotor cortex was significantly correlated with that of deactivation in the DMN in HC and RRMS, but not in SPMS. Both increased activation and decreased deactivation patterns correlated with LV.

Conclusion

In RRMS patients, increased cortical activation was associated with increased deactivation of the posterior cortex suggesting a greater resting-state activity in the DMN, probably aimed at facilitating sensorimotor circuit engagement during task performance. In SPMS the coupling between increased sensorimotor activation/increased DMN deactivation was not observed suggesting disorganization between anticorrelated functional networks as a consequence of a higher level of disconnection.  相似文献   
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Pinopodes represent the morphological and integrins, the biomollecular markers of endometrial receptivity. We studied using scanning electron microscopy, the expression of pinopodes on tubal samples and their corresponding endometria, from 21 women of reproductive age (7 from proliferative phase, 7 from day LH +5 and 7 from day LH +7). In addition, we examined the immunohistochemical staining of integrins αvβ3, αvβ5 and their ligands, fibronectin (FN) and osteopontin (OPN) in the same tubal epithelium samples. Pinopodes were detected on the tubal epithelium exclusively during day LH +7, coincident with their formation in the endometrium and synchronous to αvβ3 sharp increase in the oviduct epithelium, suggesting a regulation similar to the endometrium. In contrast, αvβ5, FN and OPN remained unchanged during the cycle. These results show for the first time the formation of pinopodes in the tubal epithelium at the time of endometrial receptivity and correlate it with the upregulation of the intact dimmer αvβ3 in the tubes.  相似文献   
10.

Background

Caveolin-1 is thought to have an important impact on both signal transduction and mediation of intracellular processes. Furthermore, it has been suggested that Caveolin-1 may contribute to certain steps of carcinogenesis in various types of cancer. We examined the potential clinical relevance of Caveolin-1 in normal, benign and malignant breast tissue specimens.

Methods

Using tissue microarray (TMA) technology cases of invasive breast cancer, DCIS, benign breast disease (i.e. fibroadenoma, sclerosing adenosis, ductal hyperplasia and radial scar) and normal breast tissue were evaluated for Caveolin-1 expression. Immunohistochemical staining with an anti-Caveolin-1-antibody was performed. Staining intensity was quantified semiquantitatively. In invasive lesions staining results were correlated with clinical and pathological data.

Results

No Caveolin-1 expression was observed in epithelial cells of normal breast tissue (n = 5), benign breast disease (n = 295) and DCIS (n = 108). However, Caveolin-1 expression was found in 32 of 109 cases of invasive breast carcinomas (29.4%). Caveolin-1 expression in invasive breast cancer could neither be correlated with survival parameters such as overall or disease-free survival nor with established clinical and pathological markers.

Conclusion

In this study we demonstrated expression of Caveolin-1 in one third of invasive breast cancers. A significant increase in Caveolin-1 expression was observed comparing invasive breast cancer to both benign breast tissue and non-invasive breast cancer. Since inhibitors of Caveolin-1 signalling are available, targeting Caveolin-1 in breast cancer may represent a potential option for future breast cancer treatment.  相似文献   
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