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1.
2.
Being able to carry zidovudine (AZT) at known concentrations into CD4+/CD38+ and CD14+ cells permits:
Further studies are necessary in order to:
相似文献
| – | - to reduce the drug dosage and to increase the interval for administration (until 1 dose I.V. every week); |
| – | - to modulate the drug concentration into the CD4+/CD38 an CD14+ cells in relation to the in vitro determined HIV sensitiveness; |
| – | - to eliminate haematological, medullary and general toxicity; |
| – | - to be able to treat severely hill patients. |
| – | - To find out the better phase to start the therapy; |
| – | - To use several drugs with different mechanisms of action in order to slow down as much as possible the presence of resistant viral strains. |
| – | - As for other drugs which are beginning to be used with artificial vehicles, futher studies are required to improve the selectivity and safety of LIPOAZT for the target cells including macrophages. |
3.
Rolf Bergmann 《Antonie van Leeuwenhoek》1989,55(2):143-152
Thiolutin was found to inhibit the utilization of glucose and other growth substrates in Escherichia coli. The inhibition was detected by a sharp drop of the respiration rate after addition of the antibiotic. The actual function affected was allocated to the cytoplasmic membrane of the bacterial cells by the following evidence:
It was concluded that the transport of certain substrates across the membrane was inhibited. 相似文献
| – | - spheroplasts were affected like intact cells, |
| – | - individual reactions of either the electron transport chain or the glycolytic pathway were not inhibited, |
| – | - glucose consumption in the culture stopped and the cells accumulated guanosine tetraphosphate as under starvation conditions, |
| – | - activation of the cell's apo-glucose dehydrogenase restored respiration via bypassing the glucose phosphotransferase system. |
4.
Phytoplanktonic populations were studied in Tazenat lake by three methods:
A comparison of the results obtained gives an insight into the utilisation and transformation of energy by the biota of the lake 相似文献
| – | Primary production using 14C technic |
| – | Standing crop estimation |
| – | Amount of chlorophyll a |
5.
R. Durand 《Mycopathologia》1976,60(1):3-16
The present review describes the effects of light on reproductive processes in fungi, mainly when action spectra are available.The study of these has resulted in three kinds of photoresponses observable in fungi:
相似文献
| – | responses only to UV light (230–380 nm) |
| – | responses to NUV and blue light (300–520nm) |
| – | responses to great wavelengths of the visible spectrum. The photomorphogenetic processes on the control of these same photoreceptor pigments are reviewed. |
6.
Culture studies with healthy and virus-infected isolates of Ectocarpus siliculosus, Feldmannia simplex and F. irregularis gave the following results:
相似文献
| – | Virus particles are produced in deformed reproductive organs (sporangia or gametangia) of the hosts and are released into the surrounding seawater. |
| – | Their infective potential is lost after several days of storage under laboratory conditions. |
| – | New infections occur when gametes or spores of the host get in contact with virus particles. The virus genome enters all cells of the developing new plant via mitosis. |
| – | Virus expression is variable, and in many cases the viability of the host is not impaired. Infected host plants may be partly fertile and pass the infection to their daughter plants. |
| – | Meiosis of the host can eliminate the virus genome and generate healthy progeny. |
| – | The genome of the Ectocarpus virus consists of dsDNA. Meiotic segregation patterns suggest an intimate association between virus genome and host chromosomes. |
| – | An extra-generic host range has been demonstrated for the Ectocarpus virus. |
| – | Field observations suggest that virus infections in ectocarpalean algae occur on all coasts of the world, and many or all Ectocarpus and Feldmannia populations are subject to contact with virus genomes. |
7.
James S. Clark 《Biogeochemistry》1990,11(1):1-22
Path analysis was used to determine the importance of long-term disturbance regime and the relative importances of correlations among vegetation patterns, disturbance history, and nitrogen (N) mineralization in old-growth forests of northwestern Minnesota. Leaf biomass (estimated by allometric equations), fire history (from fire scars on Pinus resinosa trees), and N mineralization rates (estimated from incubationsin situ) were determined from sample plots dominated by
相似文献
| – | Betula papyrifera, Populus tremuloides, andP. grandidentata |
| – | a mixture ofAcer saccharumandTilia americana, or |
| – | Quercus borealis andOstrya virginiana. |
8.
We identified three electrophoretic pathways by spectrophotometrically following the swelling of isolated yeast mitochondria:
Similarities and differences between these three electrophoretic pathways and the electrophoretic systems described in mammalian and plant mitochondria are discussed. 相似文献
| – | --An anion uniport whose activity could only be detected after depletion of divalent cations from the matrix by treatment with 1,10-phenanthroline. This uniport was inhibited by Mg2+ and dicyclohexylcarbodiimide. |
| – | --A K+(Na+) uniport which was detected only when mitochondria were suspended at low pH and low temperature. This uniport was sensitive to ruthenium red and oleic acid. |
| – | --A K+ selective uniport which was activated by alkaline pH and ATP depletion. This pathway was sensitive to glibenclamide and to various amphiphilic cations. |
9.
Gareth Rice Roland Clift Richard Burns 《The International Journal of Life Cycle Assessment》1997,2(1):53-59
Twelve of the main European LCA software packages currently available are examined wirh the aim of establishing which are
the most appropriate for LCAs on industrial processes. The packages performances are assessed in terms of
The review concludes with a Specification Table which summarises the facilities available on each software package.
The general conclusion from this study is that for industrially based LCAs, there are four packages which may offer advantages
over the rest. These are The Boustead Model, The Ecobilan Group’s TEAM™, PEMS 3.0 and SimaPro 3.1. 相似文献
| – | • Volume of Data |
| – | • WindowsTM environment |
| – | • Network Capabilities |
| – | • Impact Assessment |
| – | • Graphical representation of the inventory results |
| – | • Sensitivity analysis |
| – | • Units |
| – | • Cost |
| – | • User Support |
| – | • Flow Diagrams |
| – | • Burdens allocation |
| – | • Transparency of data |
| – | • Input & output parameters |
| – | • Demo version |
| – | • Quality of data |
10.
Nanomedical developments range from nanoparticles for molecular diagnostics, imaging and therapy to integrated medical nanosystems,
which may perform complex repair actions at the cellular level inside the body in the future.
There are three categories where MNT are applied in biomedicine
This paper will concentrate on visions and applications for drug deliveries and medical diagnostics. 相似文献
| – | • drug discovery (genomics, proteomics, HTS) |
| – | • diagnostics |
| – | • drug deliveries |
11.
Looking at the on-going discussions, integrated product policy seems to become important for the LCA community and should
therefore be reflected in the International Journal of LCA. Reasons include that IPP:
相似文献
| – | clearly follows life cycle thinking, |
| – | encourages the usage of the life cycle tool box, e.g. for product-innovation, |
| – | could become a political umbrella for a new co-operation along the life cycle - beyond the old roles of life cycle stakeholders acting on their own, |
| – | faces similar issues as the LCA community looking e.g. at environmental value / objective setting. |
12.
The active reaction upon stimulation of the femoral chordotonal organ in stick insects is known to control velocity and endpoint of flexion movements of the femur-tibia joint (Bässler 1988). This article presents evidence that spiking interneurones in the ventral anterior median part of the adjacent ganglion participate in the generation of the active reaction as well as non-spiking interneurones in the dorsal lateral region do. Three different kinds of experiments lead to this conclusion:
相似文献
| – | - Ablation of the ventral anterior median part of the metathoracic ganglion ofExtatosoma did not qualitatively alter the resistance reflex in the inactive animal but abolished the active reaction. |
| – | - Recordings from spiking interneurones in the same region of the prothoracic ganglion ofCarausius show that some of these neurones responded to a chordotonal organ stimulus in a way, which depended on the behavioural state of the animal. |
| – | - Some non-spiking interneurones, which mediate the resistance reflex in the inactive animal, respond differently during an active reaction. |
13.
| – | — Use of a 2-dimensional spectrophotometer allows the detection and analysis of spatiotemporal patterns in biological samples |
| – | — the “in vitro” system—yeast extract—behaves as an excitable medium. Oscillatory degradation of trehalose yields NADH-oscillations which, after running out, convert to spatiotemporal waves |
| – | — the observation of excitability coupled to oscillatory processes in biological systems might provide new insights into the meaning of oscillations for metabolism |
| – | — with an “in vitro” system at hand, it should be possible to perform defined experimental manipulations in order to detect the mechanism for excitability in biological systems. |
14.
Micropropagated bananas derived from Banana Bunchy-Top Virus (BBTV) infected plants, but displaying no symptoms of the disease, were established in the field. They were grown for three years and produced a plant crop and ratoon crops. No disease symptoms were observed. There was uncertainty as to whether
To resolve this question, suckers from these plants and non-infected controls were established in pots and infected with aphids, Pentalonia nigronervosa Coq, collected from BBTV-infected plants. All plants produced characteristic Banana Bunchy-Top Disease (BBTD) symptoms in five months. In addition, samples collected from the original symptomless field plants were tested by DAS-ELISA using a polyclonal antibody specific for BBTV. No detectable levels of virus were found in any of the samples. These studies support the view that the symptomless plants were virus free and not symptomlessly infected or BBTV-resistant somaclones generated from micropropagation. Nevertheless there continues to be a need for caution in dissemination of micropropagated bananas, especially when obtained from regions where BBTV is known to occur. 相似文献
| – | micropropagation eliminated the virus from the material, |
| – | the plants were symptomlessly infected, or |
| – | the plants were somaclonal variants that suppress symptom expression. |
15.
Oncostatin M, a multifunctional cytokine 总被引：6，自引：0，他引：6
16.
The conclusions about the development of the content of the LC Initiative are the following:
相似文献
| – | A specific niche for the Life Cycle Initiative has developed, compared with the role of SETAC, the International Society of Industrial Ecology (ISIE) and ISO. |
| – | The aims of the initiative have step by step been extended, by bringing the initiative at a world level, by including both LCI and LCIA, and by including a program on Life Cycle Management (LCM). |
| – | In the LCM program due attention is to be given to other tools and approaches than quantitative LCA which are relevant for life-cycle thinking in general, and also to the other two dimensions of sustainability, i.e. the social and economic dimensions. |
| – | A number of important questions regarding the scope of the initiative and the methodological set-up have been in-depth discussed, thus resulting in a clear basis for the technical content of work to come. |
| – | Three definition studies will now be implemented which will define the work program for the three programs of the initiative; these studies will be finalised by the end of 2002. |
17.
18.
Sources,fates, and impacts of nitrogen inputs to terrestrial ecosystems: review and synthesis 总被引：1，自引：0，他引：1
The relative importance of nitrogen inputs from atmospheric deposition and biological fixation is reviewed in a number of diverse, non-agricultural terrestrial ecosystems. Bulk precipitation inputs of N (l–l2 kg N ha–1 yr–1) are the same order of magnitude as, or frequently larger than, the usual range of inputs from nonsymbiotic fixation (< 1=" –=" 5=" kg=" n=">–1 yr–1), especially in areas influenced by industrial activity. Bulk precipitation measurements may underestimate total atmospheric deposition by 30–40% because they generally do not include all forms of wet and dry deposition. Symbiotic fixation generally ranges from 10–160 kg N ha–1 yr–1) in ecosystems where N-fixing species are present during early successional stages, and may exceed the range under unusual conditions.Rates of both symbiotic and nonsymbiotic fixation appear to be greater during early successional stages of forest development, where they have major impacts on nitrogen dynamics and ecosystem productivity. Fates and impacts of these nitrogen inputs are important considerations that are inadequately understood. These input processes are highly variable in space and time, and few sites have adequate comparative information on both nitrogen deposition and fixation.
相似文献
| – | - more intensive studies of total atmospheric deposition, especially of dry deposition, are needed over a wide range of ecosystems; |
| – | - additional studies of symbiotic fixation are needed that carefully quantify variation over space and time, examine more factors regulating fixation, and focus upon the availability of N and its effects upon productivity and other nutrient cycling processes; |
| – | - process-level studies of associative N-fixation should be conducted over a range of ecosystems to determine the universal importance of rhizosphere fixation; |
| – | - further examination of the role of free-living fixation in wood decomposition and soil organic matter genesis is needed, with attention upon spatial and temporal variation; and |
| – | - investigations of long-term biogeochemical impacts of these inputs must be integrated with process-level studies using modern modelling techniques. |
19.
M. V. Srinivasan R. G. Guy 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1990,166(3):287-295
| 1. | Spectral-sensitivity functions of large-field movement-detecting units in the lobula plate of the dronefly Eristalis tenax L., which is a Batesian mimic of the honeybee, were measured using visual stimuli consisting of light flashes, or moving gratings. Two classes of units were studied, one class responding to inward horizontal motion in the contralateral eye (presumably the homologue of the well-known HI in other fly species), and the other class responding to vertically-down-ward motion in the contralateral eye. |
| 2. | In both classes of units, the spectral-sensitivity function of the response to flashes is characterized by two peaks, one in the UV at ca. 350 nm and the other in the blue at ca. 475 nm (Figs. 3, 8). It resembles the spectral-sensitivity function of the R1-R6 class of receptors in other flies. |
| 3. | In both classes of units, the spectral-sensitivity function of the response to movement is characterized by a single peak, occurring in the blue at ca. 450 nm (Figs. 7, 9). |
| 4. | Control experiments on homologous units in the Australian Sheep Blowfly Lucilia cuprina, using identical stimulating conditions reveal that the response to flashes as well as movement possesses a dual-peaked spectral sensitivity, with one peak in the UV and the other in the blue-green region of the spectrum (Figs. 10–12). |
| 5. | The results indicate that the pathways subserving the inputs to movement-detecting neurons in Eristalis are driven by more than one spectral class of photoreceptors. They also reveal that the spectral sensitivity of movement detection in Eristalis bears a closer resemblance to that of the honeybee, than to that of other flies. This similarity to the honeybee may arise from the fact that the dronefly and the honeybee occupy similar ecological niches, both foraging for nectar in flowers. |
20.
Hansgeorg Rehbein 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1976,110(3):233-250
| 1. | An extracellular recording and staining technique has been used to study the structure of individual ventral-cord elements in the auditory pathway ofLocusta migratoria. |
| 2. | Three groups of auditory ventral-cord neurons can be distinguished: (a) neurons ascending to the supraesophageal ganglion, (b) T-shaped neurons, and (c) neurons limited to the thoracic ventral cord. |
| 3. | The ventral-cord neurons ascending to the supraesophageal ganglion link the auditory centers of the thorax to those of the supraesophageal ganglion. These are, at least in part, richly arborized neurons of large diameter. |
| 4. | The ventral-cord neurons with T structure send equivalent signals along both arms of the T; they resemble the neurons of the first group in that they make synaptic connections in the supraesophageal ganglion, but they also conduct auditory information to caudal regions of the thorax via the descending trunk of the axon. |
| 5. | In the supraesophageal ganglion there are several extensive projection areas of the auditory ventral-cord neurons. No direct connections to the mushroom bodies, the central body or the protocerebral bridge could be demonstrated. |
| 6. | The thoracic ventral-cord neurons act as short segmental interneurons, providing a connection between the tympanal receptor fibers and the ascending and T-shaped ventral-cord neurons. They play a crucial role in auditory information processing. |
| 7. | The possible functional properties of the various morphological sections of the auditory ventral-cord neurons are discussed, with reference to their connections with motor and other neuronal systems. |