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1.
J. Robb 《Human Evolution》1994,9(3):215-229
In recent years anthropologists have made much progress in understanding ancient activities from skeletal remains. In this
paper, material from the Iron Age cemetery at Pontecagnano (VII-IV century BC) is used to illustrate activity-related traits
of eight basic categories:
These traits, and others, can be used not only singly but in conjunction to define (a) patterns of activity and occupational
specialization for individuals, and (b) distributions within society reflecting the basic division of labor by geneder and
class. 相似文献
| (1) | idiosyncratic patterns of dental wear |
| (2) | activity-related articular degeneration |
| (3) | non-pathological functional alterations (neoformations, contact facets) |
| (4) | mechanical remodelling of bone architecture |
| (5) | enthesopathies (muscular lesions) |
| (6) | traumatic lesions |
| (7) | activity-related pathologies |
| (8) | activity-related nutritional characteristics |
2.
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 |
3.
Gustaaf M. Hallegraeff 《Aquatic Ecology》1976,10(2):87-95
| 1. | Spectrophotometric and paper chromatographic analyses have been made of pigments in the summer phytoplankton of eight lakes that widely differ in trophic characteristics. |
| 2. | A comparison has been made between Margalef's pigment ratio, the carotenoid/chlorophyll-a ratio, the pigment diversity expressed as the number of coloured spots on a paper chromatogram, and the pigment diversity calculated by using the Shannon formula. |
| 3. | No evidence has been found for an increase of diversity of phytoplankton pigments along a gradient from eutrophic towards oligotrophic lakes. |
| 4. | Pigment diversity cannot be simply used as a measure of lake maturity according to Margalef's ideas. |
4.
| 1. | The effects of potassium channel blockade on afferent axons and terminal regions in frog dorsal roots and spinal cords, respectively, were investigatedin vitro. |
| 2. | A condition-test (C-T) protocol was used to assess the population relative refractory period. Characteristics of main axons were evaluated by stimulation at the proximal end of transected dorsal roots (DR). Characteristics of terminal regions were tested by stimulation at the base of the dorsal horn (DH). |
| 3. | DH recovery of excitability was delayed by low concentrations of 4-aminopyridine (4-AP) and tetraethylammonium (TEA) alone or combined. The same treatments did not affect recovery to DR stimulation. |
| 4. | DH recovery of excitability was not delayed by solutions suppressing terminal calcium influx. |
| 5. | We conclude that sensitivity of the relative refractory period to potassium channel blocking agents differs between main axons and axon terminal regions. This may indicate differences between axon terminals and main axons in the mechanism of action potential repolarization. |
| 6. | We hypothesize that rapid action potential repolarization by pharmacologically sensitive potassium channels in presynaptic terminal regions keeps terminal action potentials short. Terminal action potential brevity would limit calcium influx, thus preventing terminal calcium overload but contributing to transmission failures at spinal synapses. |
5.
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. |
6.
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. |
7.
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. |
8.
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. |
9.
Oncostatin M, a multifunctional cytokine 总被引：6，自引：0，他引：6
10.
Structure and osmoregulatory functions of the intestinal folds in the seawater eel,Anguilla anguilla
Valérie Simonneaux Willy Humbert Raymond Kirsch 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1988,158(1):45-55
| 1. | The epithelium of the anterior intestine in the seawater eel shows very high and narrow folds whose composition and possible role in osmotic regulation were studied. |
| 2. | The enterocytes present a basal labyrinth: numerous mitochondria more or less surrounded by infoldings of the basal membrane. In the intestinal folds, the serosal tissue contains lymphocytes, fibrocytes, enterochromaffin cells, capillaries, smooth muscle fibers and collagen fibers. The tissue is less dense at the tip than at the base of the folds. |
| 3. | X-ray microanalyses and electrophysiological studies showed that the serosal, spaces are diffusive compartments sustaining ionic gradients. Na+ and Cl– activity decreased and K+ activity increased from the base to the tip of the intestinal folds. |
| 4. | Na+ or Cl– gradients are abolished when the co-ion is removed from the bathing solutions. Serosal ouabain has no reproducible effects on the ion gradients, making it impossible to determine whether these gradients result from the activity of the Na+–K+ pump. K+ gradients decreased with serosal barium and increase with mucosal barium. |
| 5. | The ion distribution in the serosal compartments together with ultrastructural characteristics are discussed. It is suggested that water absorption occurs involving a basal ion recycling mechanism. |
11.
Yasuo Nakaoka Hans Machemer 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1990,166(3):401-406
| 1. | Coupling mechanisms between ciliary beating and the membrane potential in Paramecium were investigated under voltage clamp applying intracellular pressure injection of cAMP, cGMP and Ca-EGTA buffer. Ciliary responses following step changes in membrane potential were recorded by high-speed video on magnetic tape. |
| 2. | Injections of cAMP and cGMP up to millimolar concentrations caused no detectable changes in the frequency voltage relationship. A minor effect was that the ciliary reorientation towards the anterior cell end (reversal) tended to be inhibited with depolarization up to 10 mV. |
| 3. | Injection of Ca2+ into the cell clamped at the resting potential caused a transient anteriad ciliary reorientation and a simultaneous increase in the beating frequency. |
| 4. | Injection of EGTA (to buffer Ca2+ below 10–8 M) was ineffective in relation to frequency for several minutes. After this time, hyperpolarization- and depolarization activated frequency responses of EGTA-injected cells were increasingly inhibited. The ciliary reorientation following depolarization was not affected by EGTA. |
| 5. | A posterior contraction of the cell diameter was noticed upon membrane hyperpolarization. The contraction coincided in time with the increase in beating frequency. |
| 6. | The results support the view that the voltage-dependent augmentation of the ciliary beating rate is not directly mediated by an intracellular increase in either cAMP or cGMP. |
| 7. | The role of Ca2+ as intracellular messenger in the ciliary and somatic compartments is discussed. |
12.
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. |
13.
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. |
14.
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. |
15.
16.
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. |
17.
S. Chu J. R. Kennedy 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1994,175(4):505-518
| 1. | Direct contact between intra-epithelial nerve endings and ciliated cells was observed in frog (Rana pipiens) palate epithelium. |
| 2. | Electrical stimulation of the palatine nerve to the explant or the explant culture induced an increase in ciliary beat frequency in explant and outgrowth cells. |
| 3. | Atropine inhibited electrically stimulated ciliary beat frequency increase in the explant and outgrowth cells. |
| 4. | Gap junctional intercellular communication appears to be involved in the propagation of stimulated ciliary beat frequency increase from innervated to non-innervated ciliated cells. |
18.
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. |
19.
Yasuo Nakaoka 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1989,165(5):637-641
| 1. | Paramecium bursaria was stimulated by a light spot of 10–15 m diameter, and the photosensitive site was searched by recording responses in swimming behavior and in membrane potential. |
| 2. | Local stimulation to the anterior half of the cell caused an avoiding response. |
| 3. | Stimulation to the cells deciliated by ethanol treatment elicited a depolarization of the membrane potential. |
| 4. | Local stimulation to the anteroventral portion elicited a depolarization, but stimulation to the dorsal side induced no change in the membrane potential. |
| 5. | The action spectrum of depolarization elicited by local stimulation to the anteroventral surface showed two main peaks at 420 nm and 560 nm, corresponding to those of light stimulation of the whole cell. |
| 6. | It is concluded that a photosensitive site exists on the anteroventral surface ofParamecium, in particular within the oral groove of the cell. This local photosensitivity is discussed with respect to the mating reaction. |
20.
Cannibalism in teleost fish 总被引：1，自引：0，他引：1
| 1. | Cannibalistic behaviour in fish is reviewed here for the first time. |
| 2. | Cannibalism has been recorded in 36 out of 410 teleost families according to the published literature, but is considered to be more widespread than this. Finding examples of cannibalism is not difficult, and it may be more interesting to look for taxa in which the behaviour does not take place. |
| 3. | The families that have provided the most information include the Engraulididae, Esocidae, Poeciliidae, Gasterosteidae, Percidae and Cichlidae. |
| 4. | Cannibalism has been classified into seven types, depending on life-history stage, age difference between cannibal and prey, and whether or not they are related. |
| 5. | Although in captive populations, cannibalism tends to increase with increasing density and decreasing food availability, its role in population regulation has not been unequivocally demonstrated in any wild population, and obtaining the necessary data presents a formidable challenge to fish ecologists. |
| 6. | Cannibalism is of some economic importance in aquaculture, but its impact can be reduced relatively easily, by frequent grading to reduce size variability. |
| 7. | The main proximate advantage conferred by cannibalism is assumed to be nutritional. In an ultimate sense the behaviour may have evolved as a particularly effective competitive strategy. |
| 8. | Finally, it is considered that cannibalism deserves more attention from fish biologists. Investigations, however, should recognize the different types of cannibalistic interaction, and, in particular, should explore the different implications of kin and nonkin cannibalism |