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1.
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).
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2.
The circadian rhythm in the ERG amplitude of the lateral compound eye ofLimulus can be phase shifted either by general illumination or by illuminating combinations of the photoreceptor organs.
1.  For 15-min exposures, light confined to one lateral eye, or to the median ocelli, or to the ventral photoreceptor region resulted in the smallest phase shifts.
2.  Illuminating combinations of these organs produced larger shifts. The most effective combination tested included the median ocelli, the ventral photoreceptors, and one lateral eye. The phase shift resulting from illumination of this combination was only about one-half of the shift produced by general illumination.
3.  These results suggest that the circadian clock also receives light information from other, unidentified, photoreceptors located outside the prosoma.
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3.
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:
(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
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   

4.
1.  The excitatory and inhibitory influences on the gill ofAplysia Juliana, which are mediated by the branchial nerve, were studied by means of electrophysiological techniques. Excitatory and inhibitory pathways in the nerve were stimulated simultaneously or selectively.
2.  The branchial nerve was found to contain both excitatory and inhibitory pathways which did not contain synapses in the branchial ganglion. The excitatory pathways caused longitudinal shortening of the gill along the efferent branchial vessel and the inhibitory pathways were modulatory, depressing the longitudinal shortening.
3.  Branchial nerve stimulation elicited two types of excitatory junctional potential (EJP), which were not mediated by the branchial ganglion, in a muscle cell of the efferent branchial vessel. One type was attributed to the central motor neuron and the other type to a motor neuron which is probably situated in the neural plexus of the gill periphery.
4.  Four inhibitory pathways from the central nervous system to the gill were found.
5.  Inhibitory junctional potentials (IJPs) recorded from muscle cells of the efferent branchial vessel in response to branchial nerve stimulation did not have monosynaptic characteristics. It is thought that inhibitory motor neurons which were activated by the branchial nerve might exist at the neural plexus of the gill.
6.  A single EJP which has been induced by a stimulus pulse applied to the excitatory pathway of the branchial nerve may be depressed in an all-or-none manner by a stimulus pulse applied to the inhibitory pathway, if this is done within a distinct short period prior to or after the stimulus inducing the EJP. This indicates that the central motor neuron receives presynaptic inhibition at its periphery.
7.  The motor neurons of the neural plexus seem to receive inhibitory innervation. Suppression of endogenous EJPs in the efferent vessel persisted for a long period even after cessation of stimulation.
8.  A certain branchioganglionic neuron (BGN) was found to receive inhibitory postsynaptic potential (IPSP) inputs from the branchial nerve.
9.  The multimodality of both the excitatory and the inhibitory pathways in the branchial nerve may explain the compound neural modulations of gill movements.
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5.
1.  Some units in the lateral ocellar nerves of the locust,Locusta migratoria, are influenced transsynaptically by the activity of ascending fibres in the thoracic connectives and therefore may be efferent to the afferent ocellar system.
2.  A variety of sensory inputs excite the ocellar nerve units, including illumination of the compound eyes, active and passive movement of the wings, wind stimuli to the thorax and sound.
3.  Most ocellar interneurons are influenced transsynaptically by electrical stimulation of the cervical connectives. L-neurons are depolarized and the components of their response to a rectangular light pulse are changed in amplitude. Only a few S-neurons could be examined. All of them were excited directly or indirectly.
4.  The descending ocellar interneurons (DN's) are influenced by stimulation of the contralateral connective, perhaps via efference to the ocellus or to ocellar L-cells.
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6.
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:
–  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.
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7.
Conclusions  
(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.
This work was supported byKBN grant no. 7 A203 013 07.  相似文献   

8.
1.  The dependence of dark-adapted fly (Calliphora vicina) photoreceptors on oxygen was investigated by measuring the electroretinogram (ERG), the receptor potential, and the redox states of the mitochondrial cytochromes. The redox states were determined via reflection microspectrophotometry on white-eyed fly mutants.
2.  The light sensitivity of the photoreceptors at oxygen fractions above 2% is identical to that in the normal (air) environment, as judged from both ERG and receptor potential. Light sensitivity is rather abruptly and strongly reduced at oxygen fractions lower than 1% and vanishes at anoxia (0%).
3.  The redox state of the mitochondrial cytochromes also changes around oxygen fractions of 1–2%, but the dependence on oxygen fraction is less abrupt than that of ERG and receptor potential.
4.  The mitochondrial activity of dark-adapted fly photoreceptors appears to be well-buffered, to warrant ample supply of metabolic energy for unimpaired photoreceptor function down to extremely low oxygen levels.
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9.
We have identified a nerve carrying auditory afferents and characterized their physiological responses in the tiger beetle,Cicindela marutha.
1.  The tympana are located at the lateral margins of the first abdominal tergum. The nerve carrying the tympanal afferents is a branch of the dorsal root from the first abdominal ganglion.
2.  Both male and female auditory afferent responses are sharply tuned to 30 kHz with sensitivities of 50–55 dB SPL.
3.  The auditory afferents show little adaptation and accurately code the temporal characteristics of the stimulus with the limit of a resolution of 6–10 ms.
4.  The difference in threshold between contralateral and ipsilateral afferents for lateral stimuli is greatest at 30 kHz and is at least 10–15 dB.
5.  Ablation studies indicate that the floppy membrane in the anterolateral corner of the tympanum is crucial for transduction while the medial portion of the tympanum is less important.
6.  The tiger beetle and acridid (locust and grasshopper) ears have evolved independently from homologous peripheral structures. The neural precursor of the tympanal organs in both animals is likely the pleural chordotonal organ of the first abdominal segment.
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10.
1.  Most Purkinje neurons show ongoing spike activity. In approximately 75%, this activity disappeared after peduncle lesion and in some of these the activity stopped when water flow over the gills was interrupted. Approximately one-fourth of Purkinje cells (PC's) showed continuing ongoing activity after afferent input was abolished.
2.  Stimulation of spinal cord elicited both simple spikes, mainly in ipsilateral PC's, and some complex responses (via climbing fibers) usually contralateral and of longer latency than the simple spikes.
3.  Tactile stimulation of skin and flexion of tail or fins, also lateral line stimulation by a water stream, evoked bursts of spikes in PC-s. Input was by mossy fibers and mechanoreceptive fields were large.
4.  Stimulation of vestibular nerve produced both simple and complex responses in PC's. Auditory stimuli were most effective at 800–1200 Hz in eliciting responses via mossy fibers. Responses to sound were phasic changes in ongoing frequency, bursts followed by inhibition or on-off excitation.
5.  Responses to visual stimuli were recorded in granule cells and Purkinje cells, also in mossy axons. Many PC's showed excitatory-inhibitory sequences; a few climbing fiber responses were recorded. The mossy fiber visual input is from optic tectum relay.
6.  Some PC's were activated by two or three sensory modalities.
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11.
1.  We have discovered a previously unreported visual mutant of the blowfly,Calliphora erythrocephala. It shows a reduced or absent visual performance, e.g., in escape and optomotor behavior. The effects of this mutation on the ultrastructure were studied by electron microscopy (Figs. 3–8) and on electrophysiological function, by intracellular recordings (Figs. 1 and 2).
2.  The genetic basis of this spontaneous mutation was studied by test crosses of mutant and wild-type flies. The defect appears to be in an autosomal recessive gene (Table 1).
3.  Of the mutant stock studied soon after eclosion (n = 18) 35% shows optomotor reactions, whereas only 6% studied in later life (n = 240) shows any optomotor behavior.
4.  The absence of the receptor potentials in photoreceptor cells is not directly associated with structural disorders in the early life of these mutant flies, but several types of degenerative changes are manifested in the retinular cells later on. The optomotorically blind specimens have normal (about –60 mV) resting membrane voltages but no detectable receptor cell voltage response to light, indicating a block in phototransduction. The spectral and polarization sensitivities of optomotor-positive flies are normal (Fig. 2).
5.  At the beginning of degeneration the number of lysosomes in the receptor cells is increased compared with normal flies, but their number as well as that of other components of the cell interior decrease later on. During the progression of the degeneration, the rhabdomeres shrink while the mitochondria swell and disintegrate (Figs. 6–8).
6.  The blocking of phototransduction is proposed to lead to disturbance of the turnover of the rhabdomeres and finally to degeneration of the receptor cells.
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12.
1.  The diffusive hydrogen conductance of chicken eggshell compound membrane was measured in situ on day 16 of incubation, in a direction parallel to the shell and the chorioallantois (lateral conductance). A value of 3.9 mmol d–1 kPa–1 was obtained through a ring 13.29 cm in circumference, 0.0076 cm thick and 0.3 cm long.
2.  Lateral hydrogen conductance for 1 mm2 of shell membrane 76 m thick is 30 times the conductance of one pore serving the same area.
3.  Lateral conductance for H2 is not significantly influenced by chorioallantoic perfusion.
4.  Oxygen consumption change due to partial covering of the hen eggshell indicates that there is a significant resistance to lateral diffusion of oxygen under the shell toward the covered area.
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13.
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.
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14.
1.  Non-visual sensory systems are likely to be important in antarctic fish since these fish inhabit an area where low light levels occur for long periods. This study was undertaken to examine the suitability of the lateral line system for prey detection.
2.  Recordings were made from afferent fibres of the anterior lateral line in the antarctic fishPagothenia borchgrevinki.
3.  A vibrating probe was used to stimulate the lateral line at a range of frequencies between 10 and 100 Hz.
4.  Most units responded best at a stimulus frequency of 40 Hz. Below the best frequency the response typically declined steeply and at higher frequencies it was usually better sustained.
5.  Crustacea identified as major components of the diet ofPagothenia borchgrevinki were individually attached to a force transducer to determine the vibrations produced by swimming movements.
6.  The Fourier amplitude spectra of swimming crustaceans exhibited prominent low frequency peaks at 3–6 Hz and higher frequency peaks in the 30–40 Hz range.
7.  It is concluded that the overlap in the frequency response characteristics of the anterior lateral line and the frequencies produced by crustacean prey clearly establishes the suitability of the lateral line for prey detection.
8.  In several instances recordings were made from fish primary afferent neurons responding to a swimming amphipod. These recordings confirm that crustacean swimming is indeed a potent natural stimulus of the lateral line system.
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15.
Oncostatin M, a multifunctional cytokine   总被引：6，自引：0，他引：6  
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16.
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.
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17.
Artificial magnetic fields (MF) influence physiological processes in bees.
1.  An inhomogeneous, static magnetic field (IMF) reduces the flying activity of bees and increases their life span by more than 60%.
2.  The content of the ageing pigment lipofuscin in brain and, to a lesser extent, in thorax muscles increases with the physiological age. The content of lipofuscin of the thorax muscle is only 1/5 that of the brain.
3.  Despite their increased chronological age (60–74%) brain lipofuscin of bees under conditions of an inhomogeneous, static magnetic field is slightly reduced compared with bees in natural earth's magnetic field (EMF) conditions. No effects could be registered in the muscle lipofuscin of the thorax.
4.  There was no correlation between the content of lipofuscin and the chronological age.
5.  Flying activity is also reduced by horizontal magnetic fields (0.40–1.45 Oe).
6.  Dance tempo is reduced in compensated EMF and amplified static magnetic fields (0.84 Oe). Dance tempo is drastically reduced if compensation of the EMF is followed by application of a 5 Hz magnetic field with 1.04 Oepp, directed E-W.
Dedicated to Prof. Dr. Drs. h.c. M. Lindauer on the occasion of his 70th birthday  相似文献   

18.
1.  The physiology and morphology of olfactory interneurons in the brain of larval Manduca sexta were studied using intracellular recording and staining techniques. Antennal olfactory receptors were stimulated with volatile substances from plants and with pure odorants. Neurons responding to the stimuli were investigated further to reveal their response specificities, dose-response characteristics, and morphology.
2.  We found no evidence of specific labeled-lines among the odor-responsive interneurons, as none responded exclusively to one plant odor or pure odorant; most olfactory interneurons were broadly tuned in their response spectra. This finding is consistent with an across-fiber pattern of odor coding.
3.  Mechanosensory and olfactory information are integrated at early stages of central processing, appearing in the responses of some local interneurons restricted to the primary olfactory nucleus in the brain, the larval antennal center (LAC).
4.  The responses of LAC projection neurons and higher-order protocerebral interneurons to a given odor were more consistent than the responses of LAC local interneurons.
5.  The LAC appears to be functionally subdivided, as both local and projection neurons had arborizations in specific parts of the LAC, but none had dendrites throughout the LAC.
6.  The mushroom bodies and the lateral protocerebrum contain neurons that respond to olfactory stimulation.
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19.
1.  We have described a general ribonucleotide probein situ hybridization methodology for localization of mRNA in frozen, unfixed tissue sections of brain.
2.  The most important steps in obtaining consistent and reproducible autoradiographs with ribonucleotide probes were tissue acetylation and application of the radiolabeled probe to tissue sections under unsealed, glass coverslips.
3.  Variability of the hybridization signal in tissue sections has been minimized to achieve a high degree of reproducibility within a given experiment as determined by densitometric analysis of rat glucocorticoid and mineralocorticoid receptor mRNA hybridization autoradiographs.
4.  Tissue quality has been optimized for high-resolution anatomical localization of mRNA species by nuclear track emulsion.
5.  The protocol is amenable to rapid, batchwise processing of tissue samples.
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20.
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