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1.
The results of investigations done in 1965, 1966, and 1972 on the workload of motormen of high-speed trains operating on railroads with maximum speeds of 210 km/hr were compared in an attempt to discuss the physiological implications of the driving task. The driving time of a 515 km section was 4 hr in 1965 and was lowered to 3 hr 10 min since 1966 for the fastest super-express trains. The mean heart rate was maintained around 80 beats/min during the entire driving period in 1965, but declined gradually in 1966 or 1972. Although in 1966 the operations at constant high speed appeared to favor cerebral activities, drivers in the 1972 investigation not only showed lowered perceptual and choice reaction performances but also experienced significant increase in errors in detecting signal tones given as a subsidiary task. Polygraphic recordings in 1972 indicated that drivers sometimes fell into drowsing of short duration intermittently, accompanied by temporary drop in heart rate, absence of controller action, and increase of detection errors. These effects were dominant in periods after 90 min of driving. The need to reduce the monotomy effects during underloaded train driving is suggested. 相似文献
2.
J. Linhart 《Animal genetics》1974,5(2):129-132
The blood group system E in pigs is similar to the B system in cattle, one of the most complicated of the hitherto known blood group systems.
Studies of Andresen (1957), Saison (1958), Andresen & Wroblewski (1959), Andresen et al. (1959), Andresen (1962, 1965), Rasmusen (1965), Hojný et al. (1966), Dinklage et al. (1966), Dinklage & Major (1968), Hradecký & Hojný (1972), Hojný & Hradeck (1972, 1973) lead to the determination of the various E alleles.
This report presents information of a new blood group factor Ep in pigs. 相似文献
Studies of Andresen (1957), Saison (1958), Andresen & Wroblewski (1959), Andresen et al. (1959), Andresen (1962, 1965), Rasmusen (1965), Hojný et al. (1966), Dinklage et al. (1966), Dinklage & Major (1968), Hradecký & Hojný (1972), Hojný & Hradeck (1972, 1973) lead to the determination of the various E alleles.
This report presents information of a new blood group factor E
3.
H. CASEY 《Freshwater Biology》1975,5(6):507-514
This study covers a 7-year period from 1965 to 1972, and shows the variation in flow, water chemistry and throughput of nutrients. The annual discharge of the River Frome varied considerably from year to year, ranging from a mean value of 4.48 m3 sec−1 in 1971 to one of 8.38 m3 sec−1 in 1966. The mean annual nutrient losses calculated over all 7 years of study from the River Frome catchment were: Nitrate 11.4 kg ha−1, phosphorus 0.49 kg ha−1 and potassium 8.4 kg ha−1. There has been an increase in annual throughput (in years of similar flow) of 21% in phosphate and 41% in nitrate from 1965 to 1972. 相似文献
4.
R. D. Traub 《Biological cybernetics》1977,25(3):163-176
A scheme for constructing computer models of motorneurons is presented. These model neurons display both repetitive firing and action potentials of appropriate time course; the technique combines ideas of Dodge and Cooley (1973) and Kernell and Sjöholm (1972, 1973). This scheme is used to construct models of motorneurons of different input resistance (and hence different geometry) in order to examine Kernell's (1966) observations that (a) small motorneurons require a lower injected current to begin firing than do large motorneurons; but (b) the slope of the injected current-firing rate curve is less for small neurons than large. It is concluded that this behavior is not a simple consequence of the cell geometry, but requires different time courses for a slow conductance across the cell membrane. This observation is consistent with the experimentally observed differences in time course of afterhyperpolarization between large and small cells (Eccles et al., 1958). The models are used to study input-output relations for motorneurons when the input is a steady conductance change on the cell membrane, possibly in conjunction with an injected current. Comparisons are drawn with the experimental observations of Kernell (1965a, 1965b) and Chaplain and Schaupp (1973). It is shown that the observations of Henneman et al. (1965a, 1965b) and Milner-Brown et al. (1973a, 1973b) on the order of recruitment of motorneurons under conditions of natural stimulation may be explained by the following version of the size principle: a given input to a pool of motorneurons causes equivalent conductance changes on each cell of the pool—here equivalent means the input is distributed to corresponding portions of the soma-dendritic tree and is of equal magnitude in mhos. Hypotheses are offered as to how this distribution of input may be accomplished in Nature. 相似文献
5.
T he N ormal biochemical maturation of postsynaptic adrenergic neurons in mouse and rat superior cervical ganglion depends upon an intact preganglionic innervation (B lack , H endry and I versen , 1971a, 1972; T hoenen , S aner and K eitler , 1972). In recent studies tyrosine hydroxylase, the rate-limiting enzyme in norepinephrine biosynthesis (L evitt , S pector , S joerdsma and U denfriend , 1965), with localization to adrenergic neurons in the ganglion (B lack , H endry and I versen , 1971b), was used to monitor maturation of these cells. The developmental increase in tyrosine hydroxylase activity occurred simultaneously with the appearance of ganglionic synapses and was prevented by transection of the preganglionic nerve trunk (B lack , H endry and I versen , 1971a). These observations suggest that presynaptic cholinergic nerve terminals regulate the biochemical development of postsynaptic neurons in the superior cervical ganglion. The mechanism(s) by which presynaptic cholinergic terminals regulate postsynaptic development has not been elucidated. Such trans-synaptic regulation may be dependent on normal impulse transmission and/or may involve other unidentified, trophic factors. The results presented in the present communication suggest that normal development of ganglionic tyrosine hydroxylase activity is dependent on depolarization of postsynaptic adrenergic neurons. 相似文献
6.
P E Crossen 《Humangenetik》1975,27(2):151-156
The banding patterns of chromosomes from 20 patients with chronic lymphocytic leukaemia (C.L.L.) have been analyzed. 97 of 100 metaphases examined had a normal banding pattern. The 3 remaining metaphases, all from one patient had bands similar to those seen after aging. It is concluded that the chromosomes in C.L.L. have normal banding patterns. The majority of cytogenetic studies in chronic lymphocytic leukaemia have reported normal chromosomes (Fitzgerald and Adams 1965; Oppenheim et al., 1965; Lawler et al., 1968). An inherited abnormality of G group chromosome (No. 22) has been reported in a family, three members of whom developed C.L.L. (Fitzgerald and Hamer, 1969), but further investigations of cases of familial leukaemia failed to reveal a similar abnormality (Fitzgerald et. al., 1966). The development of new techniques which allow the positive identification of individual chromosomes (Caspersson et al., 1969; Dutrillaux and Lejeune, 1971; Sumner et al., 1971; Seabright, 1971), has revolutionised human cutogenetics and revealed additional information regarding chromosome abnormalities and leukaemia (Rowley, 1973; Lobb et al., 1972; Milligan and Garson, 1974). The purpose of this investigation was to determine whether the chromosomes in C.L.L. have normal banding patterns. 相似文献
7.
8.
R. DENNELL F.L.S. 《Zoological Journal of the Linnean Society》1974,54(3):241-245
Fine closely-packed parallel fibres pass obliquely, at an angle of about 10° to the horizontal, through the cuticles of Cancer and Carcinus . They lie on axes parallel to the four faces of an obtuse pyramid, and have no counterpart in the model proposed by Bouligand (1965, 1971, 1972).
Replication of vertically broken surfaces of cuticle on cellulose acetate film shows that the laminae of the cuticle are discrete structural entities which preserve their identity around the angle formed by two vertical faces meeting at right-angles. This does not conform to the requirements of the Bouligand model. 相似文献
Replication of vertically broken surfaces of cuticle on cellulose acetate film shows that the laminae of the cuticle are discrete structural entities which preserve their identity around the angle formed by two vertical faces meeting at right-angles. This does not conform to the requirements of the Bouligand model. 相似文献
9.
The largest genus of the phylum Sipuncula is reviewed and a key provided to the six subgenera. Some historical comments are provided, particularly with reference to the recent monograph by Stephen & Edmonds (1972). It is noted, in concurrence with Gepner's (1965) views, that despite its large size, Golfingia is a natural unit and probably reflects the site of most rapid cladogenesis as well as being the most generalized, primitive genus. Ten species names (abnormis, cantabriensis, charcoti, derjugini, iniqua, kolense, pavlenkoi, profunda, pusilla, and sluiteri) are synonymized as well as one generic name (Nephasoma). The motivating force behind many of these changes was our consideration of species as populations rather than types. This work is based on the inspection of several type specimens as well as the authors' extensive experience with this genus. 相似文献
10.
Alan Y. K. Wong Ph.D. 《Bulletin of mathematical biology》1973,35(3):375-399
Based on A. V. Hill's three-component model, mechanical properties of the contractile element (CE), such as velocity and tension,
were determined as muscle shortening and loads in quick-release or afterloaded isotonic contraction. The method is applicable
for studying cardiac mechanics, to obtain force-velocity data of the same CE length at varous afterloads.
Analysis of the energetics of cardiac muscle was based on simulation studies of cardiac mechanics (Wong 1971, 1972). By proper
derivation, the conventional contractile element work (CEW) was found to be a minor energy determinant. The tension-time integral
and tension-independent heat (Ricchiuti and Gibbs, 1965) represent energy utilization for activation and maintenance of tension,
the primary energy determinant. 相似文献
11.
The occurrence of larval Anisakis in North Sea herring was examined during the period 1965-1972 using a sampling method which yielded comparable data for all eight years. Data on abundance of infestation in several herring stocks pointed to remarkable fluctuations over the study period with an increase in the period 1966-1968 followed by a decrease in the period 1968-1972. Of various hypotheses that may explain this situation, it is concluded that changes in the migration behaviour of the herring may be responsible. Other data and statistics are discussed with special reference to variations in infestation level in different samples and to the occurrence of adult nematodes in marine mammals. 相似文献
12.
H Lachnit 《The Pavlovian journal of biological science》1986,21(4):160-172
An empirical evaluation of temporal aspects of contextual conditioning was conducted in relation to Asratyan's (1965) theory of transswitching and to an alternative explanation that was partly stimulated by the Rescorla-Wagner model (Rescorla and Wagner 1972). On the basis of a human electrodermal conditioning preparation suggested by Kimmel and Ray (1978), five groups with 12 subjects each were run. The results indicated that the basic phenomena of transswitching are robust and therefore could be replicated; but the Asratyan theory was rejected. All the results supported an alternative explanation: in contextual conditioning, duration of contextual stimuli is less important than order. Phasic switching is due to simultaneous occurrence of stimuli (differential compound conditioning) and is therefore compatible with the Rescorla-Wagner model. Tonic switching is due to signals that occur before a marked sequence of conditioning trials, in part a challenge to the Rescorla-Wagner model. Long delays between critical events can perhaps be compensated for by mediating memory processes. 相似文献
13.
M. H. Robertson 《BMJ (Clinical research ed.)》1973,4(5884):84-85
The prevalence of tetracycline-resistant beta-haemolytic streptococci in South-west Essex has been recorded over the past 10 years. It has fallen from a peak of 35% in 1965 to a level of 9·2% in 1972. Ear infections no longer provide the highest incidence of these organisms; vaginal, perineal, and skin infections now seem to be of greater relative importance but throat swabs still provide the greatest actual number of isolations. Erythromycin-resistant strains are still rare. 相似文献
14.
Infectious pancreatic necrosis (IPN) is a disease of salmonid fishes. It has been reported in many countries throughout the world (M’Gonigle 1940, Wood et al. 1955, Besse & Kinkelin 1965, Vestergård Jørgensen & Bregnballe 1969, Sano 1971, Ball et al 1971, Ljungberg & Vestergård Jørgensen 1972, Schlotfeldt et al. 1975). Outbreaks of the disease can cause serious losses in populations of hatchery reared salmonids, the mortality rate varying between 10 and 90 % (Vestergård Jørgensen & Kehlet 1971). There are at least four different serotypes of the virus distinguished by neutralization tests (Wolf et al. 1968). Twenty-five isolates of IPN virus in Denmark proved to represent only two serotypes (Sp and Ab) (Vestergård Jørgensen & Kehlet). The present paper reports the first isolation of IPN virus from the stock at a fish farm in Norway. 相似文献
15.
I. Singh I. S. Chohan M. Lal P. K. Khanna M. C. Srivastava R. B. Nanda J. S. Lamba M. S. Malhotra 《International journal of biometeorology》1977,21(2):93-122
Prolonged stay at high altitude significantly lowers the incidence of some of the diseases commonly encountered at sea level. This conclusion is based on a study involving 130,700 men stationed on plains between 760 m and sea level and 20,000 men stationed at altitudes between 3692 and 5538 m during the period 1965 to 1972. When yearwise differences in morbidity rates were determined for this period it was found that apart from amoebic hepatitis, goitre and lobar pneumonia, which show a higher incidence, the incidence of infections of bacterial, viral and protozoal origin, diabetes mellitus, hypertension and ischaemic heart disease, asthma and rheumatoid arthritis, gastric disorders, skin diseases, psychiatric ailments and anaemia was significantly lower at high altitude than at sea level. When the trend in morbidity rates was compared over the two subperiods of 1965 to 1968 and 1969 to 1972 it was found that generally increasing or decreasing trends on plains were reflected at high altitude. The overall incidence at high altitude however remained low. Part I of our communication deals with epidemiological data and these findings. Part II surveys the available literature and attempts to explain how improved hormonal state, enhanced fibrinolytic activity, accelerated humoral and cellular immune responses, favourable haemodynamics, better cardiac and cerebral functions, improved metabolic functions, and a relatively stable, dry and cold climate favourably influence the incidence of diseases at high altitude. 相似文献
16.
17.
D. J. Hunt 《Systematic parasitology》1983,5(3):215-221
Summary
Indiana gryllotalpae is redescribed from the gut of a mole-cricket, Scapteriscus sp., from Trinidad. The structure of the cephalic umbraculum (comprising 6 major and 6 minor cuticular elements extending back from the setulose lip region) is described in detail by use of both light and scanning electron microscopy. I. gryllotalpae of Bain (1965) is regarded as a synonym of I. coimbatoriensis Latheef & Seshadri, 1972. ac]19820729 相似文献
18.
The mammalian-type cytochrome c of the basidiomycete Ustilago sphaerogena contains in a single polypeptide chain of 107 residues, two histidine residues located at positions 18 and 33, and one methionine residue situated at position 80 (Bitar et al., 1972). The reaction of Ustilago ferricytochrome c with bromoacetate at neutral pH resulted in the modification of histidine-33, but not of histidine-18 or of the invariant methionine residue. The activities of Ustilago cytochrome c with mitochondrial cytochrome c oxidase and with NADH-cytochrome c reductase were unaltered by the modification. The equilibrium constants for the formation of low-spin complexes of the ferrihaem octapeptide of horse cytochrome c (residues 14-21, including the haem bound covalently to cysteines 14 and 17) with imidazole, N(2)-acetylhistidine and monocarboxymethyl derivatives of N(2)-acetylhistidine were determined spectrophotometrically. Alkylation of the imidazole side-chain group of N(2)-acetylhistidine resulted in a marked decrease in its ability to form low-spin ferrihaem complexes. These results indicate that in Ustilago ferricytochrome c in solution histidine-33 is not involved in the central co-ordination complex. Since side-chain groups of residues other than histidine and methionine do not appear to be involved in the central complexes of other mammalian-type cytochromes c (Hettinger & Harbury, 1964, 1965; Myer & Harbury, 1965) it is likely that in Ustilago ferricytochrome c in solution at neutral pH, the side-chain groups of histidine-18 and methionine-80 are involved in the central co-ordination complex. The latter is stable over the pH range 2.6-8.4. 相似文献
19.
There is agreement that uterine infection is necessary for the development of the varied picture of clinical pyometra which includes changes in the kidneys and other organs (Børresen 1975). Some important clinical manifestations of the pyometra syndrome have been explained in terms of an endotoxinaemia (Asheim 1964, Schalm 1965). 相似文献
20.
根据江苏泰县N-4井五通组观山段顶部的胞石Grahnichitina pilosa的发现,确定观山段的时代为中泥盆世吉维特期。据此认为:擂鼓台段的两层暗色泥岩,应分别对比为南洞页岩、长顺页岩;中泥盆世大海侵时,华南海沿苏皖河经皖南、苏南入侵苏北。对Grahnichitina pilosa进行描记和讨论。 相似文献