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181.
The study concerns the adrenocortical glucocorticoid responsiveness to the ACTH 1-17 analogue given at different times of the day, namely near to the zenith and the nadir of the circadian curve of plasma cortisol. Two schedules of administration of the heptadecapeptide have been performed: a pulse i.v. injection of 4 microgram; b. i.m. injection of 100 microgram. Both the doses were given to the same subject in the morning and in the evening of different days. The chrono-sensitivity of the adrenal cortex to ACTH 1.17 analogue is well evident after pulse stimulation by a micro-dose of the heptadecapeptide; in fact the plasma cortisol increase from basal values is significantly higher in evening than in the morning (p less than 0.001). The cortico-stimulatory effect of the higher dose of ACTH 1.17 analogue lasts about 12 h. and then plasma and urinary glucocorticoids take the usual circadian pattern again.  相似文献   
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Interstitial deletion of long arm of chromosome 13   总被引:2,自引:0,他引:2  
The case is presented of a patient with the karyotype 46,XX,del(13q)(pter----q22::q32----qter) confirmed by densitometry and a phenotype of mental and growth deficiency, hypotonia, hypertelorism, ptosis, broad nasal bridge, protruding upper incisors, short neck, dislocation of the hip, hypoplasia of the thumbs, fusion of fourth and fifth metacarpal bones and syndactyly of toes. The findings are compared with those of well documented cases with a similar deleted segment of the long arm of chromosome 13. Although it seems obvious that a clinical syndrome for the distal deletion 13q appears to exist more studies with banded chromosomes are needed.  相似文献   
184.
The Miocene carbonate deposits of Scontrone (Abruzzo, Central Italy) are well known among palaeontologists because of their fossil vertebrate content that exhibits striking similarities to those of the remarkable “Terre Rosse” faunal complex of the Gargano region, defining the existence of the Miocene Central Mediterranean Apulia paleobioprovince. The main goal of this paper is to establish the age and environment of the Scontrone vertebrate bonebeds. The vertebrate remains are embedded in the basal portion of the Lithothamnion Limestone, a widespread carbonate-ramp lithosome representative of the Tortonian-early Messinian transgression over the entire Apulia Platform. The bonebeds belong to marginal-marine deposits (here called “Scontrone calcarenites”) preserved in a small area below transgressive ravinement surfaces. The rapid vertical and lateral facies variations displayed by the “Scontrone calcarenites”, together with paleoenvironmental considerations deriving from the vertebrate association, document a complex wave-dominated river-mouth depositional setting developed over a large, flat and semi-arid carbonate ramp. The “Scontrone calcarenites” have been split herein into five facies associations representing the stratigraphic response to a discontinuous or punctuated transgression within an overall rise of the relative sea level. Because of the absence of age-diagnostic fossils, the age of the “Scontrone calcarenites” cannot be directly defined through their paleontological content. However, a regional stratigraphic correlation between the Lithothamnion Limestone of Scontrone and the Lithothamnion Limestone of northern Majella, which is biostratigraphically well constrained, allows the attribution of the “Scontrone calcarenites” to the Tortonian.  相似文献   
185.
†Pycnodontiformes was a successful lineage of primarily marine fishes that broadly diversified during the Mesozoic. They possessed a wide variety of body shapes and were adapted to a broad range of food sources. Two other neopterygian clades possessing similar ecological adaptations in both body morphology (†Dapediiformes) and dentition (Ginglymodi) also occurred in Mesozoic seas. Although these groups occupied the same marine ecosystems, the role that competitive exclusion and niche partitioning played in their ability to survive alongside each other remains unknown. Using geometric morphometrics on both the lower jaw (as constraint for feeding adaptation) and body shape (as constraint for habitat adaptation), we show that while dapediiforms and ginglymodians occupy similar lower jaw morphospace, pycnodontiforms are completely separate. Separation also occurs between the clades in body shape so that competition reduction between pycnodontiforms and the other two clades would have resulted in niche partitioning. Competition within pycnodontiforms seemingly was reduced further by evolving different feeding strategies as shown by disparate jaw shapes that also indicate high levels of plasticity. Acanthomorpha was a teleostean clade that evolved later in the Mesozoic and which has been regarded as implicated in driving the pycnodontiforms to extinction. Although they share similar body shapes, no coeval acanthomorphs had similar jaw shapes or dentitions for dealing with hard prey like pycnodontiforms do and so their success being a factor in pycnodontiform extinction is unlikely. Sea surface temperature and eustatic variations also had no impact on pycnodontiform diversity patterns according to our results. Conversely, the occurrence and number of available reefs and hardgrounds as habitats through time seems to be the main factor in pycnodontiform success. Decline in such habitats during the Late Cretaceous and Palaeogene might have had deleterious consequences for pycnodontiform diversity. Acanthomorphs occupied the niches of pycnodontiforms during the terminal phase of their existence.  相似文献   
186.
A new set of 14 chloroplast microsatellites, represented by mono‐ and dinucleotide repeats, was optimized in the three main species of the Fagaceae (Castanea sativa, Fagus sylvatica and Quercus petraea). The intraspecific variation was tested in some natural populations. The polymorphic microsatellites displayed two or three variants. Conservation of the primer pairs was checked on an additional set of six species of the Fagaceae and on Fraxinus excelsior. All the primer pairs produced a fragment of the expected size in the Fagaceae species while no amplification was obtained with 36% of the primers in F. excelsior.  相似文献   
187.
The Eocene whiptail stingrays of the family Dasyatidae from the Bolca Lagerstätte, NE Italy, are revised herein in detail. The analysis of the anatomical and morphometric features allows us to identify the species “Dasyatis zigni (Molin, 1861) as a junior synonym of “D. muricatus (Volta, 1796), and to assign it to the new genus Tethytrygon gen. n. This new taxon exhibits a unique combination of features (e.g., rhombic disc wider than long, elongated tail folds fail to reach the tip of the tail, thorns absent, single serrated tail sting, “caniniform” teeth on upper jaw, tooth crown ornamentation absent, 175–179 vertebrae, 108–117 pectoral radials, 24–27 pelvic radials and other features of clasper anatomy) that clearly support its attribution to the subfamily Neotrygoninae of the stingray family Dasyatidae. The morphological and phylogenetic affinities of Tethytrygon gen. n. with the living neotrygonines (Neotrygon and Taeniura) suggest a close association of this taxon with the tropical shallow‐water habitats hypothesized for the Bolca palaeoenvironment during the early Eocene. Moreover, the analysis of the fossil occurrences of the neotrygonines provides new insights into the role of the Tethys for the origin and evolutionary history of certain whiptail stingrays.  相似文献   
188.
Here we report the first record of one of the most common and widespread Palaeogene selachians, the sand tiger shark Brachycarcharias, from the Ypresian Bolca Konservat-Lagerstätte. The combination of dental character of the 15 isolated teeth collected from the Pesciara and Monte Postale sites (e.g. anterior teeth up to 25 mm with fairly low triangular cusp decreasing regularly in width; one to two pairs of well-developed lateral cusplets; root with broadly separated lobes; upper teeth with a cusp bent distally) supports their assignment to the odontaspidid Brachycarcharias lerichei (Casier, 1946), a species widely spread across the North Hemisphere during the early Palaeogene. The unambiguous first report of this lamniform shark in the Eocene Bolca Konservat-Lagerstätte improves our knowledge concerning the diversity and palaeobiology of the cartilaginous fishes of this palaeontological site, and provides new insights about the biotic turnovers that involved the high trophic levels of the marine settings after the end-Cretaceous extinction.  相似文献   
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