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1.
Conclusions
This work was supported byKBN grant no. 7 A203 013 07. 相似文献
| (1) | The aminoesters inhibit glucose-stimulated proton extrusion by yeast cells. |
| (2) | The inhibitory activity depends on aliphatic carbon chain length. |
| (3) | The inhibition of proton extrusion is concentration-dependent. |
| (4) | The aminoesters stimulate quinacrine accumulation in vacuoles of yeast cells so they should possess affinities for lysosomes. |
2.
This paper reviews research results on food competition between a freshwater fish community and a breeding Tufted duck population. After the experimental removal of fish from the Main Lake, the following effects were observed:
相似文献
| (1) | 1. Invertebrate (chironomid and gastropod) food for ducklings and adult Tufted ducks increased substantially. |
| (2) | 2. Tufted duckling brood use of the lake increased greatly and Tufted duckling survival appears to have increased. |
| (3) | 3. Shoveler and Pochard nested successfully for the first time. |
| (4) | 4. Submerged aquatic macrophytes grew profusely over the lake bed for the first time leading directly to large increases in use of the Lake by wintering herbivorous waterfowl. |
| (5) | 5. When fish were re-introduced to the Main Lake sampling bay the increases in invertebrate abundance and, to a less marked extent, macrophyte abundance were reversed. |
3.
Oncostatin M, a multifunctional cytokine 总被引：6，自引：0，他引：6
4.
Jiří Doskočil 《Molecular and cellular biochemistry》1976,10(3):137-143
| (1) | The inactivation of various forms of nucleoside transport with reagents blocking thiol groups was studied in whole cells ofE. coli B. No positive correlation between the efficiency of active transport and the extent or rate of inactivation could be demonstrated. |
| (2) | The most efficient constitutive nucleoside-transporting system was found to comprise a specific thiol component characterized by low rate of inactivation with N-ethylmaleimide; the less efficient inducible transport and the facilitated diffusion of guanosine require the integrity of another thiol component which is rapidly inactivated with N-ethylmaleimide. |
| (3) | The constitutive nucleoside-transporting system is completely inactivated with T4 phage, while other modes of nucleoside transport are much less affected. |
| (4) | Inactivation of constitutive transporting system in cells exposed to N-ethylmaleimide for a limited period of time continues long after the inhibitor has been removed, indicating storage of the inhibitor in some cellular compartment. Addition of dithiothreitol stops the inactivation immediately. |
5.
To compare the efficiency of various whole cell immobilization techniques for the production of gluconic acid by Aspergillus niger were investigated using potassium ferrocyanide-treated cane molasses as the substrate. The techniques followed were:
A comparative analysis of yield has revealed that calcium alginate entrapment was the most suitable technique as it had given the maximum product yield (0.40 g gluconic acid/g total reducing sugar supplied). The properties of immobilized A.niger in sodium alginate gel have been thoroughly investigated and compared with those of free cells under most suitable conditions of fermentation. 相似文献
| (1) | Calcium alginate entrapment, |
| (2) | cross-linking with glutaraldehyde after cell permeabilization with (a) acetone, (b) toluene and (c) isopropanol and |
| (3) | development of granular catalyst. |
6.
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 |
7.
Victy Mercy Gerald 《Hydrobiologia》1976,49(2):103-109
| 1. | At 28°C conversion efficiency of total nitrogen (TN) was inversely related to size. |
| 2. | In the pre-adult stage protein nitrogen (PN) conversion efficiency was high whereas in the Post-adult stage non-protein nitrogen (NPN) conversion efficiency was high. |
| 3. | Lower temperature (20°C) was not congenial for PN conversion. |
| 4. | Higher temperature favoured PN conversion for smaller fish but NPN for larger fish. |
8.
A method for quantitative evaluation of light sources from the point of their suitability for algal cultivation is described. Two parameters are used for the evaluation:
相似文献
| (1) | amount of photons emitted in the spectral region absorbed by algae per consumed unit of electrical energy; |
| (2) | fraction of photons intercept by the algae that got effectively transformed into chemical energy. |
9.
Ueda Junichi Miyamoto Kensuke Saniewski Marian Hoshino Tomoki Utsunomiya Maki Okubo Hiroshi 《Acta Physiologiae Plantarum》2002,24(2):187-194
Methyl jasmonate (JA-Me) promoted leaf abscission of succulent plant, Crassula lycopodioides, and exudation from stems and leaves after leaf abscission when it was sprayed in whole plants. Major component of the exudate
was identified as sucrose based on the results described below.
In addition, potassium and sodium were found in the exudate as major inorganic cations. These results suggest that exudate
of Crassula lycopodioides is phloem sap, and JA-Me promotes the excudation due to the inhibition of the synthesis of callose in sieve tubes of succulent
plants. 相似文献
| (1) | The reaction of the excudate was not positive in the Somogyi-Nelson method but in the phenol-sulfuric acid method. |
| (2) | The exudate was hydrolyzed with invertase of Candida utilis, after that showing a positive reaction in the Somogyi-Nelson method. |
| (3) | Only glucose and mannose were identified in the exudate after hydrolysis with trifluoroacetic acid using a gas-liquid chromatograph (GLC). |
| (4) | A single peak corresponding to the retention time of sucrose was observed using a high performance liquid chromatograph (HPLC). |
10.
In this report we describe the most suitable protocol for callus formation and plant regeneration for cotton. We screened 15 cotton (Gossypium hirsutum L.) genotypes for metal resistance and two of them, Nazilli M-503 (M503) Nazilli 143 (N-143) selected as Cd, Cu and Ni resistant. The cotyledonary nodes from these genotypes were the best explants for regeneration of shoots (more than 90 %) and roots (50 to 70 %). Shoot apex also gave good shoot regeneration (more than 90 %) but their root regeneration efficiency was low (35 %). These results show that Murashige and Skoog (MS) media containing 0.44 μM naphthaleneacetic acid (NAA) and 0.98 μM indole-3-butyric acid (IBA) was the most suitable recipe for getting high shoot and root regeneration from cotyledonary nodes of N-143 and M503 cotton genotypes.Abbreviations
This work was supported by the Textile Industry grant No. F000301 given to A.R. Memon. 相似文献
| 2,4 D | 2,4-dichlorophenoxyacetic acid |
| BAP | 6-benzylaminopurine |
| GA | gibberellic acid |
| IBA | indole-3-butyric acid |
| MS medium | Murashige and Skoog medium |
| NAA | naphthaleneacetic acid |
11.
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. |
12.
In the rift valley (North-East of France/South-West of Germany), the Rhine runs freely for 300 km from South to North. The absence of natural obstacles allows the development of a very regular profile of the river. We have therefore an opportunity to study very gradual modifications of the alluvial forest communities of the fluvial corridor from upstream to downstream, according to the gradual evolution of the ecological factors, related to slope decrease and hydrological modifications.We describe, from Basel to Mainz:
相似文献
| 1) | modification of dynamic processes in the forest communities such as successional sequences or sylvigenetic mosaïcs of the terminal stages. |
| 2) | modification of species richness. |
| 3) | reduction of species diversity. |
| 4) | simplification of the forest stratification. |
| 5) | modification of efficiency of the biogeochemical cycling. |
| 6) | ecological vicariances. |
| 7) | modification in species behaviour. |
13.
3DFS is a 3D flexible searching system for lead discovery. Version 1.0 of 3DFS was published recently (Wang, T.; Zhou, J. J. Chem. Inf. Comput. Sci., 1998, 38, 71–77). Here version 1.2 represents a substantial improvement over version 1.0. There are six major changes in version 1.2 compared to version 1.0.
Besides the above, this paper supplies:
Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1007/s0089490050231 相似文献
| 1. | A new rule of aromatic ring recognition. |
| 2. | The inclusion of multiple-type atoms and chains in queries. |
| 3. | The inclusion of more spatial constraints, especially the directions of lone pairs. |
| 4. | The improvement of the query file format. |
| 5. | The addition of genetic search for flexible search. |
| 6. | An output option for generating MOLfiles of hits. |
| 1. | More query examples. |
| 2. | A comparison between genetic search and Powell optimization. |
| 3. | More detailed comparison between 3DFS and Chem-X. |
| 4. | A preliminary application of 3DFS to K+ channel opener studies. |
14.
Dr. Diethard Sanders 《Facies》2000,42(1):227-243
Summary On Kos island, Greece, along an investigated coastal segment 3 km in length, four adjacent sectors were distinguished, (1)
Empros beach, a rocky shore with plunging cliffs and a steeply dipping, submarine talus, (2) Thermi beach, a „coarse-clastic
beach” with a subaerial cliff fringed by a bouldery to coarse gravelly beach with poorly developed zonation, (3) Dimitra beach,
a gravelly beach with well-developed zonation, and (4) Phokas beach, a gravelly beach characterized by finer mean grain size.
The lateral variation in Holocene coastal morphology would lead to different transgressive records: „rapid” sea-level rise
that may be suggested by transgression of the rocky shore is contemporaneous with „gradual” rise recorded by transgression
of the gravelly beaches.
Dimitra beach is an about 500 m long, cuspate, microtidal, wave-dominated gravelly beach. From land offshore, in its fairweather
configuration it shows
During storm upbuilding, the foreshore sand flats disappeared, the gravel ridges were eroded and an even, more gently dipping
storm beachface developed. Beach restoration in a swell regime proceeded in feedback with the emergent fairweather beach morphology.
During ensuing fairweather, the foreshore sand flats were partly winnowed. On Dimitra beach the layer involved in beach face
to uppermost shoreface dynamics was about 1 m thick and 10–15 m wide. In fossil gravelly beach successions, features formed
during highenergy events include both berms and master bedding surfaces. Features of the waning stage are fairweather plunge
steps and relic storm/swell beachfaces (lower beachface). From cuspate gravel ridges of the upper beachface probably only
the basal part is preserved. 相似文献
| (a) | a backshore of rounded gravels to small, rounded boulders, |
| (b) | a winter storm berm paved by disc-shaped clasts, |
| (c) | a belt of beach cusps each centered by an oblique-triangular foreshore sand flat, and flanked by gravel ridges of roughly triangular shape in plan view, |
| (d) | a fairweather plunge step, |
| (e) | a. „relic storm/swell beachface” (uppermost shoreface during fairweather) of clean, rounded coarse gravels to cobbles, |
| (f) | a storm/swell plunge step, and |
| (g) | a vencer of gravels to boulders that, farther seaward, grades into submarine sand flats. |
15.
Victy Mercy Gerald 《Hydrobiologia》1976,49(1):77-85
| 1. | The overall rate of feeding at 28°C bears an inverse relationship to size; the time course of feeding appears to be size-independent and shows a decline with increase in time. |
| 2. | Absorption efficiency is independent of size. |
| 3. | The rates of absorption and conversion and conversion efficiency are inversely related to size. |
| 4. | The rate of feeding is reflected on the rates of absorption and conversion. |
16.
P. Kloppenburg J. Erber 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1995,176(1):111-118
| 1. | The effects of the biogenic amines serotonin and octopamine on motion-sensitive neurons in the lobula of the honey bee were analysed electrophysiologically. Single cell activity was recorded intracellularly during application of amines. Field potentials in the lobula were recorded to measure the effects on populations of motion-sensitive neurons. |
| 2. | Serotonin and octopamine modulate the response properties of motion-sensitive neurons in the lobula in a functionally antagonistic way. |
| 3. | The application of serotonin, in most cases, reduces background activity as well as responses to moving stripe patterns by motion-sensitive lobula neurons. The direction specificity can also decrease after serotonin application. In accordance with the single cell recordings, the amplitudes of lobula field potentials evoked by moving stripe patterns are also reduced by application of serotonin. |
| 4. | Octopamine leads to an increase in the amplitude and the initial slope of field potentials evoked by moving stripe patterns. However, there were no uniform effects at the single cell level after octopamine application. |
| 5. | The modulatory effects of serotonin and octopamine on motion-sensitive neurons correlate well with some behavioral modifications elicited by these substances (Erber et al. 1991; Erber and Kloppenburg, companion paper). |
17.
Wang Yusheng 《Plant Ecology》1992,98(1):83-95
| (1) | The influence of sheep grazing of moderate grazing (MG), heavy grazing (HG), inordinate grazing (IG), over grazing (OG), and extinct grazing (EG) on vegetation succession was studied in the Stipa baicalensis steppe during 1984–1986. |
| (2) | The relationships between the relative sum of dominance ratio (RSDR) and the degree of succession (DS) at all stages of grazing succession in the Stipa baicalensis steppe were revealed in terms of the method of mathematical analysis under five grazing intensities mentioned above. |
| (3) | The dynamic models of grazing succession that are based on accurate grazing intensities in relation to succession courses were constructed using RSDR5, and DS. The models may explain the rules of grazing succession in the Stipa baicalensis steppe. |
18.
19.
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. |
20.
Morten Buhl Jørgensen Barbara Schmitz Jakob Christensen-Dalsgaard 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,168(2):223-232
| 1. | We used laser vibrometry and free field sound stimulation to study the frequency responses of the eardrum and the lateral body wall of awake male Eleutherodactylus coqui. |
| 2. | The eardrum snowed one of two distinct frequency responses depending on whether the glottis was open (GO response) or closed (GC response) during the measurement. |
| 3. | The lateral body wall vibrated with a maximum amplitude close to that of the eardrum and in the same frequency range. |
| 4. | Covering the frog's body wall with vaseline reduced the vibration amplitude of the GC response by up to 15 dB. |
| 5. | When a closed sound delivery system was used to stimulate a local area of the body wall the eardrum also showed one of two types of responses. |
| 6. | These results suggest that sound is transmitted via the lung cavity to the internal surface of the eardrum. This lung input has a significant influence on the vibrations of the eardrum even when the glottis is closed. |
| 7. | The vibration amplitude of the eardrum changed with the angle of sound incidence. The directionality was most pronounced in a narrow frequency range between the two main frequencies of the conspecific advertisement call. |