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11.
Radiolarians from the Upper Triassic of the allochthonous Mamonia Assemblage of southern Cyprus are considered. The Phasoula Formation, composed of basic volcanics, with lenses and interbeds of micritic limestones and cherts, contains (1) a Lower Norian assemblage with Capnodoce crystallina-Trialatus robustus, which also includes Capnodoce anapetes De Wever, Capnuchosphaera deweveri Kozur et Mostler, C. theloides De Wever, Deflandrecyrtium curvatum Kozur et Mostler, Icrioma cruciformis Tekin, Kahlerosphaera norica Kozur et Mock, Kinyrosphaera helicata Bragin, Mostlericyrtium sitepesiformis Tekin, Palaeosaturnalis latiannulatus Kozur et Mostler, Spongostylus tortilis Kozur et Mostler, Xiphotheca rugosa Bragin, and Zhamojdasphaera proceruspinosa Lahm; (2) a Middle Norian assemblage with Capnodoce sarisa accompanied by Loffa mulleri Pessagno, Nabolella trispinosa Bragin, and Praexehasaturnalis tenuispinosus (Donofrio et Mostler); and (3) an Upper Norian assemblage with Livarella densiporata-Lysemelas olbia accompanied by Pentactinocarpus sevaticus Kozur et Mostler, Praemesosaturnalis multidentatus (Kozur et Mostler), and others. This assemblage also occurs in clastic turbidites of the Vlambouros Formation. In the sections of southern Cyprus, radiolarian zones are recognized that correspond to the zones previously established in the Far East of Russia, which include Capnodoce crystallina (Lower and Middle Norian) and Lysemelas olbia (lower part of the Upper Norian). Radiolarians belonging to three orders, 24 families, 59 genera, and 101 species are described; of them 2 genera, 9 species, and 1 subspecies were previously described by the author; 14 new species and 1 new subspecies are established. The diagnoses of many genera and species are emended, the stratigraphic and geographical ranges of the majority of taxa are substantially expanded.  相似文献   
12.
The activity of the neurones of the medial septal region (MS) and the hippocampal EEG in control and during the appearance of seizure discharges provoked by electrical stimulation of the perforant path were investigated in the awake rabbit. During afterdischarge generation in the hippocampus the dense neuronal bursts separated by periods of inhibition were recorded in the MS. In one group of neurons the bursts of spikes coincided with the discharges in the hippocampus, in other group-occured during inhibitory periods. When the afterdischarge stopped, in the septal neurons with theta activity the disruption of theta pattern was recorded, which have been correlated with the occurrence of low amplitude high frequency (20-25 Hz) waves in the hippocampal EEG. As a rule, the neuronal activivity of the MS recovered much quickly than EEG of the hippocampus; in some cases the increasing of the theta regularity was observed. The definite accordance of the electrical activity of the hippocampus and MS during seizure discharges suggests that the septohippocampal system operate as integral nervous circuit in these conditions. Diverse in the temporal interrelations between the discharges of MS neurones and ictal discharges in the hippocampus in the different cells possible indicate that various groups of the septal nervous elements have different participation in the seizure development. Appearance of the high frequency bursts in the MS is a possible "precursor" of the seizure onsets.  相似文献   
13.
Genetic analyses on noninvasively collected samples have revolutionized how populations are monitored. Most noninvasive monitoring studies have used hair or scat for individual identification of elusive mammals, but here we utilize naturally shed feathers. The Eastern imperial eagle (EIE) is a species of conservation concern throughout Central Asia and, like most raptors, EIEs are inherently challenging to study because adults are difficult to capture and band using conventional techniques. Over 6 years, we noninvasively collected hundreds of adult feathers and directly sampled EIE chicks at a national nature reserve in Kazakhstan. All samples were genetically sexed and genotyped at a suite of microsatellite loci. Genetically profiled adult feathers identified and monitored the presence of individual eagles over time, enabling us to address a variety of issues related to the biology, demography, and conservation of EIEs. Specifically, we characterized (i) the genetic mating system, (ii) relatedness among mated pairs, (iii) chick sex ratios, and (iv) annual turnover in an adult breeding population. We show that EIEs are genetically monogamous and furthermore, there is no apparent relatedness-based system of mate choice (e.g. inbreeding avoidance). Results indicate that annual adult EIE survivorship (84%) is lower than expected for a long-lived raptor, but initial analyses suggest the current reproductive rate at our study site is sufficient to maintain a stable breeding population. The pristine habitat at our study site supports an EIE population that is probably the most demographically robust in the world; thus, our results caution that populations in marginal habitats may not be self-sustaining.  相似文献   
14.
During oxydase reaction spectral characteristics of ceruloplasmin at absorption of copper ions and protein part of the molecule are shown to change. It has been ascertained, that when irradiating ceruloplasmin by UV-light the functioning of intramolecular electron transport chain is broken, the degree of positive cooperativity (a Hill's constant) on substrate decreases. It is supposed, that these changes are caused by disturbance of interdomain interactions in a protein molecule.  相似文献   
15.
Sexual behaviour and testosterone output in response to a receptive female were investigated in male mice of three inbred strains BALB/cLac, CBA/Lac and PT at puberty (45 days of age) and in adulthood (90 days of age). The animals were exposed for 10 min to a receptive female separated by a plastic grill, which would not allow contact between male and female. Male and female behaviour was recorded by measuring the time the male or female spent at the grill and the number of approaches to it (sexual motivation). The grill was then removed and the number of mounts and chemoinvestigatory behavior towards a female (nasal and anogenital sniffing) was recorded for each male. An increase in serum concentration and testicular content of testosterone was used as an endocrine index of the sensitivity to female pheromones. It has been shown the significant genotype and developmental effects on sexual behaviour and the hormonal response to sexual stimuli. The pubertal BALB/cLac males were characterised by the adult pattern of sexual motivation, chemoinvestigatory behaviour and the evident testosterone respond to a female. Males of the strain PT showed the lowest sexual motivation, chemoinvestigatory behavior towards a receptive female and no testosterone responses at both ages. This is a very different situation with the CBA/Lac's who showed the developmental increase in the sexual motivation, sniffing behaviour and the endocrine reflex, and the highest level of sexual behaviour but the moderate testosterone respond to a female at adulthood. The data obtained suggest genotype related asynchrony in maturation of the olfactory system, pituitary-gonadal axis and neural circuits of sexual behavior, and their independent genetic control. So, the set of mice strains investigated represents a useful tool for genetic and endocrine study of sexual behavior and the chemosensory control of testicular steroidogenesis.  相似文献   
16.
Significant increase of dopamine (DA) in hypothalamus and epinephrine (E) in the brain stem were revealed in the experiment on rats with experimental gastric ulcer (EGU). An acupuncture (AP) session produces a prominent increase in DOPA and especially DA in hypothalamus of the rat with EGU. Under the same conditions A, DOPA and DA in the brain stem increased as compared to the control. It is assumed that acupuncture produces a correcting effect on the reconstructive processes of catecholaminergic systems of the brain occurring in visceral pathology.  相似文献   
17.
In experiments on rats with experimental ulcer of the stomach (EUS) using spectrofluorometric method the increase of DOPA and dopamine (DA) in brain stem, has been revealed as well as DOPA in hypothalamus. Change of the level of DOPA takes place at an early stage of ulcer formation. Acupuncture (AP) inserts essential corrections into the distribution of catecholamines under study. So, the content of DOPA and DA in hypothalamus and particularly in the brain stem in rats with EUS against the background of AP sharply increases. It has been supposed that AP realizes its therapeutic influence during ulcer disease due to the alteration of catecholaminergic brain system.  相似文献   
18.
Blood capillaries have been studied electron microscopically in the areas of grafts (rat embryonal hippocamp and septal cerebral parts transplanted to mature rats) containing mainly nervous, glial or connective tissue cells. Certain differences in the capillary wall structure have been revealed. In areas with a great concentration of nervous cells, the blood capillaries are characterized by a dense arrangement of cellular elements in their walls, a continuous layer of the glial end-feet, this is specific for the CNS capillaries providing the blood--brain barrier. In peripheral area of the grafts, where glial elements predominate, the capillaries have loose arrangement of the mural cellular elements, great endotheliocyte activity, thick connective tissue tunic, lack of a dense glial surrounding. These characteristics make dubious the statement whether these capillaries possess the blood--brain barrier function. In places where connective tissue cells make aggregates, the capillaries do not possess the barrier properties because of perforations and fenestrae in endothelium and interruptions of the basal membrane, absence of pericapillary glial elements. All types of the capillaries demonstrate certain signs of a high functional activity. Formation of the capillary structure depends on the surrounding tissue.  相似文献   
19.
Summary DNA fingerprinting of nestlings ofFalco cherrug was used to determine indirectly the survival of the corresponding adult parent birds, which are difficult to catch in sufficient numbers. This approach is possible because Saker falcons show a high degree of site and mate tenacity. DNA profiles of nestlings from the same territory but from different years were compared. Three patterns of band-sharing coefficients between broods from the same territory were found: if band-sharing coefficients within and between broods from consecutive years were similar but significantly different from those of unrelated birds, it indicated that all young were full sibs and that neither adult was replaced between years. If band-sharing coefficients between broods at the same site indicated no relatedness across years and were equal to those of unrelated birds, then both breeding partners apparently had changed. If the band-sharing coefficients between broods of the same territory and consecutive years were significantly lower than those of full sibs, but higher than those of unrelated birds, the loss of one adult bird was indicated. The analysis of 32 broods (years 1993 to 1997) provided a minimal estimate for annual adult survival of 82% for a wild population of Saker Falcons in Kazakhstan.
Abschätzung der jährlichen Überlebensraten des Sakerfalken(Falco cherrug) mittels DNA-Fingerprinting
Zusammenfassung Um die Gefährdung und Populationsdynamik des Sakerfalken (Falco cherrug) beurteilen zu können, benötigen wir genaue Angaben zu Mortalität und Überlebensraten. Während es bei dieser Art relativ einfach ist, Nestlinge zu fangen, ist es nahezu unmöglich, eine ausreichend große Zahl an Altvögeln zu markieren, um durch Wiederfang oder Ringfundmeldungen die jährliche Überlebensrate zu ermitteln. Durch DNA-Fingerprinting von Jungfalken haben wir versucht, die minimale Überlebensrate von Altfalken indirekt zu bestimmen. Dieser Forschungsansatz wird dadurch möglich, daß die Sakerfalken eine hohe Philopatrie aufweisen und jedes Jahr im selben Revier brüten. Wenn man mehrere Jahre lang Blutproben der Jungvögel aus denselben Revieren sammelt, so kann man mittels DNA Fingerprinting indirekt ermitteln, ob die jeweiligen Altvögel identisch waren oder gewechselt haben: Vergleicht man die Band-Sharing-Koeffizienten (BSK) von Jungvögeln von zwei oder mehr Jahren aus demselben Revier, so ergeben sich drei Muster: Wenn die BSK-Werte innerhalb der Bruten und zwischen den Bruten identisch aber signifikant verschieden von denen nicht verwandter Vögel sind, so handelt es sich bei den Jungvögeln um Vollgeschwister; demnach sind die Altvögel identisch geblieben, d. h. sie haben von einem Jahr zum nächsten überlebt. Wenn die BSK-Werte zwischen zwei Bruten aus demselben Revier einen Wert annehmen, wie man ihn für unverwandte Tiere ermittelt, so müssen die Eltern gewechselt haben. Liegen die Werte zwischen zwei Bruten signifikant höher als die von nicht verwandten Tieren, aber niedriger als diejenigen von Vollgeschwistern, so ist vermutlich 1 Altvogel gewechselt worden. Die Analyse von 32 Bruten des Sakerfalken aus Kasachstan zeigt, daß die minimale jährliche Adultüberlebensrate bei 82% liegt.
  相似文献   
20.
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