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1.
The effect of unilateral tonic muscle activity with and without co-activation of the antagonists on motor cortex excitability has been studied. Motor evoked potentials (MEPs) were recorded from the first dorsal interosseus muscles of both hands in response to transcranial magnetic stimulation (TMS) during relax, isometric index finger abduction and antagonistic co-activation. The intracortical inhibition (ICI) and intracortical facilitation (ICF) were investigated by paired-pulse TMS with interstimulus intervals of 3 and 13 ms. The unilateral tonic activation of the right hand facilitated contralateral and ipsilateral responses (cMEP and iMEP) recorded from both hands with an exception of iMEPs recorded from the left hand. During paired-pulse TMS ICI for cMEPs was not influenced by the unilateral tonic activity in both hands, while ICF was suppressed when MEPs were recorded from the active right hand. The effect of unilateral tonic activity on iMEP in response to paired-pulse TMS was essentially different: generally, ICI was greater for iMEPs and ICF was completely abolished with an exception of iMEPs recorded from the left hand during right finger isometric abduction when a strong ICF was evident. The decreased ICF and/or increased ICI are assumed to reflect mechanisms underlying the co-activation of antagonists.  相似文献   

2.
Abstract: Vocalizations were recorded from a captive juvenile Bryde's whale, Balaenoptera edeni , that stranded off the gulf coast of Florida (Pinellas Co.) and was held at Sea World of Florida. The most common vocalization was a pulsed moan with durations of 0.5–51 set and acoustic energy from 200–900 Ht. Although these sounds are unlike any reported previously from this species, there are similarities to moans recorded opportunistically during a feeding study of free-ranging B. edeni in the Gulf of California (GOC). The pulsed moans recorded from Bryde's whale adults in the GOC were shorter in duration (0.7–1.4 set) than those recorded from the captive juvenile, but the frequencies were similar (165–875 Hz). In addition, a series of discrete, regularly spaced pulses (interpulse interval = 0.5–1.0 set, 700–950 Hz) were recorded only in the presence of Bryde's whale calves in the GOC.
Pulse rates produced by the captive juvenile (20–70 pulses/set) were intermediate between those recorded in the presence of GOC adults (60–130/sec) and calves (10–20/set). With these limited data it is not possible to determine to what extent the intermediate qualities of the juvenile call reflect maturational differences in the sound production apparatus, a phase of learning to vocalize like an adult, or the characteristics of a context-dependent call not recorded in the GOC.  相似文献   

3.
西藏兰科一新记录属——冷兰属   总被引:1,自引:0,他引:1  
对西藏拉萨河流域的兰科植物进行了分类学研究,发现1个西藏新记录属(冷兰属)及属下新记录种(冷兰),并附有新记录种的特征照片。  相似文献   

4.
The luteolytic potency of fenprostalene (a PGF2alpha analog) is about 20-times that of naturally produced PGF2alpha. The objective of this research was to investigate the uterokinetic effects of fenprostalene at a luteolytic dosage (1.0 mg) in the cyclic and early postpartum cow, and in the isolated uterine horn. Uterine motility measurements were conducted on two consecutive days in each cow. Experimental protocol on Day 1 was: spontaneous motility was recorded for 1 h; fenprostalene was injected (1.0 mg i.m.), after which motility was recorded for 2 h; fenprostalene was injected (1.0 mg i.v.) and motility was recorded for 30 min; and oxytocin was injected (40 U i.v.), followed by a 30-min recording period. On Day 2, the treatment sequence was reversed: spontaneous motility was recorded for 1 h; oxytocin was injected (100 U i.m.), after which motility was recorded for 2 h; fenprostalene was injected (1.0 mg i.v.) and motility recorded for 30 min; and oxytocin was injected (40 U i.v.), followed by a 30-min recording period. In the in vitro experiment, different dosages of fenprostalene (5.9, 11.8, 17.6, and 29.4 ng/ml bath solutions) and oxytocin (0.06, 0.12, 0.18, and 0.60 mU/ml bath solutions) were tested in pairs for 1 h. The treatment was then repeated. In a different group, fenprostalene (5.9 ng/ml bath solution) and oxytocin (0.06 mU/ml bath solution) treatments were alternated. Fenprostalene (at luteolytic dosage) was not uterokinetic in either the cyclic or postpartum cow. However, fenprostalene and oxytocin had a significant uterokinetic effect (five- to six-fold pretreatment value) on the isolated uterine horn preparation at all dosages studied. Peak motility occurred between 10 to 15 min, followed by a gradual decrease to 40% at 60 min. When the treatments were repeated at 60 min, oxytocin but not fenprostalene caused a minute, transient contraction. However, fenprostalene-desensitized (by exposure to fenprostalene) uteri reacted significantly to oxytocin, and vice versa.  相似文献   

5.
An atmospheric survey at human height (1.5–1.8 ft) was carried out from February 1988 to January 1990, in four different ecozones of the Delhi metropolis. The samples were collected by using Burkard Personal Volumetric Sampler at weekly intervals. The sampler was operating for 15 min three times a day (07, 14, 20 hrs). Altogether, 84 pollen types were identified. Some of the dominant pollen types recorded were Poaceae (25.1%), Cheno/Amaranthaceae (14.5%) and Ricinus communis (12.3%) followed by Morus, Cannabis, Prosopis, Parthenium and Artemisia. Weekly variations were recorded for the total number of pollen of different types in different months. Two major pollen seasons 1. February — April and 2. August — October were observed, although pollen was recorded throughout the year. Significant variation in total and individual pollen concentration was recorded from different inhabited areas in the same urban locality. Any definite daily pattern in the occurrence of pollen was not recorded. The concentration at lower height was also poor.  相似文献   

6.
A bioreporter was made containing a tfdRP(DII)-luxCDABE fusion in a modified mini-Tn5 construct. When it was introduced into the chromosome of Ralstonia eutropha JMP134, the resulting strain, JMP134-32, produced a sensitive bioluminescent response to 2, 4-dichlorophenoxyacetic acid (2,4-D) at concentrations of 2.0 microM to 5.0 mM. This response was linear (R(2) = 0.9825) in the range of 2.0 microM to 1.1 x 10(2) microM. Saturation occurred at higher concentrations, with maximal bioluminescence occurring in the presence of approximately 1.2 mM 2,4-D. A sensitive response was also recorded in the presence of 2,4-dichlorophenol at concentrations below 1.1 x 10(2) microM; however, only a limited bioluminescent response was recorded in the presence of 3-chlorobenzoic acid at concentrations below 1.0 mM. A significant bioluminescent response was also recorded when strain JMP134-32 was incubated with soils containing aged 2,4-D residues.  相似文献   

7.
Two different MFC configurations designed for handling solid wastes as a feedstock were evaluated in batch mode: a single compartment combined membrane-electrodes (SCME) design; and a twin-compartment brush-type anode electrodes (TBE) design (reversed T-shape MFC with two-air cathode) without a proton exchange membrane (PEM). Cattle manure was tested as a model livestock organic solid waste feedstock. Under steady conditions, voltage of 0.38 V was recorded with an external resistance of 470 Ω. When digested anaerobic sludge was used as the seed in the SCME design, a maximum power density of 36.6 mW/m2 was recorded. When hydrogen-generating bacteria (HGB) were used as the seed used in the TBE design, a higher power density of 67 mW/m2 was recorded.  相似文献   

8.
The optically recorded action potentials of the frog atrial muscles which lack transverse tubules showed different features from those reported by Heiny and Vergara (Heiny JA, Vergara J. Optical signals from surface and T system membranes in skeletal muscle fibers. J Gen Physiol 1982;80:203-230) in skeletal muscles (Fujishiro N, Kawata H. The wavelength dependence of optically recorded action potentials in the atrial muscles of the bullfrog (Rana catesbeiana). Comp Biochem Physiol 1996;114A:153-157). We examined whether or not the differences were consistent in other atrial muscles which lack transverse tubules with guinea pig atrial muscles. Two dyes (merocyanine rhodanine and merocyanine oxazolone) were used, and the dependence of the maximum rising phase of the optical signals on the wavelength of the incident beam was analyzed. No dependence was observed between them, and this finding was consistent with the structure of the membrane system of the guinea pig atrial muscles. The optical signals recorded at 718 nm of the incident beam from the guinea pig atrial muscles which stained with merocyanine oxazolone showed a more prominent second rising phase after the initial rapid rising phase of the optical signal than that recorded in the frog atrial muscles. This phase was not observed in the optical signals recorded at other wavelengths. The features of the optically recorded action potentials in guinea pig atrial muscles were consistent with those recorded in frog atrial muscles. Nifedipine did not affect the second rising phase.  相似文献   

9.
Three species of blind Amphipoda are recorded from anchihaline cave waters in the Galapagos Islands. One of these, Galapsiellus leleuporum (Monod, 1970) was previously know from the islands; the male is described for the first time. The other two belong to families with predominantly (though not exclusively) deep-sea members: Valettietta cavernicola sp. nov. (family Lysianassidae; and Antronicippe serrata gen. et sp. nov. (family Pardaliscidae). The genus Valettietta was not previously recorded from caves; it contained two abyssal species in the Atlantic, while a third species was recorded from the Pacific in a vertical haul between 0 and 5300 m. Antronicippe is closely related to Spelaeonicippe , a genus with two species known from anchihaline caves in the Canary Islands and the West Indies.  相似文献   

10.
Cerebral evoked potentials (EPs) were recorded in 25 neurologically normal subjects aged 22–73 years (mean 44.0) after stimulation of the posterior urethra (PU) and the pudendal nerve. After maximal PU stimulation 2 different configurations of the potential were found. In 12 cases a simple bi-triphasic wave form was recorded while in 12 cases there was a bifid form of the first negative wave. In 1 case identical EPs were recorded after PU and pudendal nerve stimulation.It was concluded that (1) PU stimulation excites fibres in the pudendal nerve at higher stimulation strength, resulting in a bifid wave form of the cerebral evoked potential in some individuals, (2) the most prominent negative peak, N1, with a latency of 102.1 ± 13.2 msec, is the most reproducible part of the PU-evoked potential, (3) the N1 is probably transmitted through Aδ fibres localized in the pelvic nerves, (4) there are differences between individuals concerning pudendal and pelvic nerve involvement in afferent innervation of the urethra.  相似文献   

11.
The article describes the epidemiological characteristics of Q fever in Croatia, during the period before and after the Homeland War. In the ten years prior to the Homeland War (1983-1992) 1053 cases of Q fever were recorded, 16.2% (171) of which on islands and in coastal areas. In the period after the Homeland War (1995-2008), a total of 654 cases was recorded, 59.9% (392) of which on islands and in coastal areas. In addition to reduced incidence, geographic distribution of the disease also changed. Before the war, the highest morbidity rate was recorded in the Sisak-Moslavina County. After the war, the Split-Dalmatia County recorded the highest morbidity rate because in the post-war period sheep from Bosnia and Herzegovina went to this county for winter grazing. The disease might be relevant to the Croatian Army and other armed forces that stay in Croatia as part of NATO forces.  相似文献   

12.
ABSTRACT

Marine strandlines provide habitat for a variety of littoral and terrestrial invertebrates, including arachnids. In this study we recorded spiders in strandlines at 35 sites on Banks Peninsula, New Zealand. On average, only 1.5 named species were recorded per thirty-minute hand search, and many sample visits (30%) recorded no spiders. Species accumulation curves suggested further species could be recorded with further sampling, but these may be tourist species rather than strandline residents. Thirty-eight species were recorded in total, with the introduced theridiid Steatoda capensis being the most common (30 records) and widespread (17 locations). The New Zealand endemic species Otagoa nova (25 records) (Toxopidae), Anoteropsis litoralis (15) and Anoteropsis hilaris (15) (Lycosidae), and the introduced Tenuiphantes tenuis (24) (Linyphiidae), were also common. Spiders were more frequent in strandlines on boulder beaches compared with shingle beaches, although there was no statistical differences in the numbers of species recorded on the different beach types.  相似文献   

13.
Seasonality of biomass and agar yield from two agarophytes (G. cervicornis and H. cornea) was determined. The biomass from G. cervicornis was higher (390 g m-2) during the dry season and lower during the rainy season (129 g m-2). The data analysis for G. cervicornis revealed a significant seasonal variation (P < 0.05). H. cornea did not show a clear seasonal variation and was present only from March to August. The peak in biomass for this species was recorded in April (383 g m-2) and was significantly different from the other months (P < 0.05). The agar yield for G. cervicornis varied from 11% to 20%, with generally higher values recorded during the dry season. The agar yield showed a highly significant variation (P < 0.001). Agar yield from H. cornea ranged from 29% to 41%, with a peak recorded in June. The results above indicate that H. cornea can be considered a good candidate for commercial use.  相似文献   

14.
A somatosensory potential that is evoked by transient added inspiratory load has previously been described (Davenport PW, Friedman WA, Thompson FJ, and Franzen O. J Appl Physiol 60: 1843-1848, 1986). This evoked potential is novel because it arises in response to a stimulus that also evokes a muscle response, and so this potential could contain myogenic components. The present study was undertaken to define the relationship between the scalp response and other physiological responses that are evoked by airway occlusion. Evoked signals were recorded from the scalp, scalenus anterior, masseter, and electrooculogram. Responses to a 200-ms midinspiratory occlusion were recorded in 12 healthy volunteers. Evoked responses were reliably recorded at C(3)-C(Z) and C(4)-C(Z) and from the skin overlying the scalenus anterior in 11 of these subjects. The onset latencies were 15.7 +/- 3.1 at C(3)-C(Z), 15.9 +/- 2.1 at C(4)-C(Z), and 17.6 +/- 5.5 ms at scalenus anterior. In nine subjects, the masseter response appeared to coincide with the mouth pressure trace, and this was interpreted as movement artifact. No consistent electrooculogram or frontal electroencephalogram response was recorded. Because of the similarity in onset latency at C(3)-C(Z), C(4)-C(Z), and scalenus anterior, it was concluded that the myogenic signal may contribute to the scalp response and should be viewed as a potential source of artifact in experiments of this nature.  相似文献   

15.
A selection experiment was initiated in 1996 in which selection for (HP line) and against (LP line) feather pecking was performed. The foundation stock was a White Leghorn layer strain established in 1970 and maintained since then as a random bred control line at the Institute. Six hatches were produced over three generations. At the age of 68 weeks (generation 0, 1996), 35 weeks (generation 1, 1997), 30 weeks (generation 2, 1998), and 27 weeks (generation 3, 1999) female birds were transferred to observation pens and their feather pecking behaviour was recorded. In each generation, 30 females and 8 males were selected from approximately 200 females and 60 males. The selection criterion was breeding value estimated by animal model on the trait 'number of bouts of feather pecking per bird per hour'.Feather pecking behaviour in adult hens was significantly higher in HP than in LP. In generation 2 the following was recorded: 3.10 versus 1.37 bouts per bird per hour (P<0.01), 7.04 versus 3.58 pecks per bird per hour (P<0.05) and the proportion of hens recorded feather pecking in the 180min observation period was 67 versus 56% (P<0.05). In generation 3 the following was recorded: 4.56 versus 0.63 bouts per bird per hour (P<0.001), 13.9 versus 2.51 pecks per bird per hour (P<0.001) and the proportion of hens recorded feather pecking in the 180min observation period was 75 versus 49% (P<0.001).In generation 3, plumage condition was better in LP on neck, breast, back, wings and tail, as well as overall (P<0.001). Body weight did not differ between lines in generation 2, but in generation 3, HP hens were on average heavier than LP hens at the age of 27 weeks (1435g versus 1371g, P<0.001).  相似文献   

16.
The electrical activity of the right and left sensorimotor and premotor cortical areas and right and left medulary reticular formation was recorded during "animal hypnosis" in rabbits. In this state, the spectral power of potentials (predominantly, in the delta-range) recorded from the left reticular formation was higher than that recorded from the right side. The value of the function of coherence between the right and left reticular recordings was decreased to 0.1-0.2 in the whole frequency range. The tight-side intrahemispheric coherence between the activities recorded from the sensorimotor cortex and reticular formation was higher than respective left-side values, whereas the coherent relations between the activities recorded from the reticular formation and premotor cortex were not changed (as compared to nonhypnotic state).  相似文献   

17.
Summary Cross sections (1–2 mm thick) of the ray (Raja) tail were secured to a dish and immersed in elasmobranch saline. Spontaneous miniature excitatory junction potentials (MEJPs) were recorded by advancing a 50 k, KCl filled electrode into the electric organ (20 V peak-to-peak baseline noise). Data were filmed, and/or recorded on magnetic tape for computer analyses. Intracellularly recorded MEJP amplitude histograms showed a peak at 60 V and had a right-hand skew with MEJPs up to 0.5 mV. The small peak amplitude and the skewed amplitude distribution of intracellularly recorded MEJPs result from the relatively low input resistance and the short space constant of the electrocyte coupled with the dispersed synapses on the electrocyte. At 23 °C the intracellularly recorded MEJP frequency ranged from 1–10 MEJPs/s. The MEJPs became larger and became focally recorded as the electrode was advanced against the intracellular surface of the innervated membrane of the electrocyte. Focal extracellular MEJPs (reversed polarity) were also recorded with the electrode positioned against the outside surface of the innervated side of the electrocyte. The frequency of focally recorded intracellular MEJPs was increased (up to 40/s) when the electrode was pushed against the membrane. Focal MEJP frequencies decreased to a few/min within 5–10 min but the mean amplitude of 3–5 mV remained constant. Decreases in amplitude and frequency in focally recorded intracellular MEJPs are attributed to changes in electrode pressure against the membrane. Amplitude histograms were constructed from focally recorded intracellular or extracellular MEJPs which showed the same time characteristics. The focal MEJP amplitude histograms have two distinct classes, each forming a bell-shaped distribution. It is concluded that both classes are generated at the electrode tip. The smaller class of MEJPs has a mean 1/10th that of the larger class and composes about 2% of the MEJPs. The small class is analogous to the sub-MEPP class found in the frog sartorius (Kriebel and Gross 1974) and mouse diaphragm (Kriebel et al. 1976, 1982). Distributions of synaptic vesicle diameters are slightly log normal (right hand skew) such that the mean diameter (57 nm) is slightly larger than the modal value (52 nm). Vesicles touching the membrane were of the same size and diameter distribution as the entire vesicle population. The profiles of the distributions are smooth and suggest only 1 class of synaptic vesicle based on diameter.  相似文献   

18.
《L'Anthropologie》2019,123(1):180-188
African rituals and beliefs have been recorded by various observers (travelers and anthropologists) in different areas in southern Africa within the last two centuries, and these are useful for interpreting prehistoric rock art (paintings and engravings). Notably, Lichtenstein (1812) recorded rituals among Nguni (who interacted with San) in South Africa, where a hunter took on the form of an animal which was symbolically wounded and which was symbolically killed in the belief that this would contribute to success in a forthcoming hunt. In Namibia, Lebzelter (1934) recorded another ritual in which a San hunter symbolically wounded and symbolically killed an animal represented in a drawing. Such rituals relate to the principle of sympathetic hunting magic. The ethnological evidence is discussed in relation to prehistoric rock art in different areas of southern Africa (Wonderwerk Cave in South Africa, Apollo 11 Cave in Namibia, and Melikane Shelter in Lesotho), and in relation to an important photograph of a ritual presumed to be associated with hunting, recorded at Logageng in the southern Kalahari, South Africa. When taken together with linguistic as well as ethnographic evidence, these sources of information support the view that the so-called trance hypothesis (relating to shamanism) and the principle of sympathetic hunting magic are not mutually exclusive, at least in southern Africa (if not elsewhere).  相似文献   

19.
OBJECTIVE--To investigate how parents use bronchodilator treatment for relief of symptoms when treating their asthmatic preschool children. DESIGN--A commercial electromechanical timer device was attached to a large volume spacer to record the time and date of each use of inhaled bronchodilator over two months. The recorded time and dates were compared with symptoms noted in an asthma diary card. SETTING--Large paediatric teaching hospital in Glasgow. SUBJECTS--29 preschool children with moderately severe asthma attending a specialist paediatric asthma clinic. MAIN OUTCOME MEASURES--Inhaler use measured by the timer device; symptoms and inhaler use recorded by parents in a daily asthma diary. RESULTS--Satisfactory data were obtained in 22 of the 29 children; the median number of study days was 53 (range 18-77). Asthmatic symptoms were recorded on a median of 30 (3-77) days. Bronchodilator was used on a median of 19 (2-73) days, or on 63% (7-100%) of days when symptoms occurred. The median number of puffs used in a day was 1 (range 0-100) and was significantly related to symptom severity in only 14 of the 22 children. In only two of the 22 children was bronchodilator given more frequently than four hourly, and only five children ever used more than 12 puffs a day. CONCLUSIONS--The frequency of parental administration of bronchodilator treatment was variable and not closely related to the parent''s record of symptom severity. Parents often recorded symptoms in their children but did not treat them.  相似文献   

20.
Respiratory-related evoked potentials (RREPs) have been elicited by inspiratory loads in adults and children. The RREP was recorded over the somatosensory region of the cerebral cortex. It was hypothesized that a RREP could be recorded by using expiratory occlusion. Electroencephalographic activity was recorded in adults from 14 scalp locations, referenced to the linked earlobes. The occlusion was presented as an interruption of expiration. Epochs of electroencephalographic activity and mouth pressure were recorded for each expiratory occlusion presentation. There were two occlusion trials and a control trial of 100 presentations each. The epochs in each trial were averaged and examined for the presence of short-latency, occlusion-related peaks. RREP peaks were observed bilaterally with expiratory occlusion and were absent in control unoccluded averages. A positive peak, P(34), was observed at central and postcentral sites. A negative peak, N(53), was observed at frontal and central sites. A second positive peak, P(95), was observed at frontal and central sites. These results demonstrate that expiratory occlusion elicits a RREP. This suggests that expiratory occlusion-related sensory information activates the cerebral cortex similar to that for inspiratory loads.  相似文献   

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