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271.
A number of postcranial specimens of Neosaimiri fieldsi, a Middle Miocene platyrrhine, were discovered in 1988, 1989, and 1990 at La Venta, Colombia. Until recently only three postcranial specimens of this species had been discovered and the present material adds further information about this taxon's postcranial morphology. In overall skeletal dimensions and in postcranial features, Neosaimiri is most similar to Saimiri among extant medium-sized platyrrhines, but differs from Saimiri in having more rugose surface markings, a longer olecranon, a smaller anterior process of the distal tibia, an absence of a distal surface extension on the anterior tibial shaft, an absence of an anterior midtrochlear depression of the talus, and a shorter distal calcaneus relative to the calcaneal tuberosity. These differences suggest that Neosaimiri was relatively heavily built, possessed a more dominant forelimb in quadrupedal progression, and utilized a less stabilized upper ankle joint, and a shorter power arm for plantarflexion. Neosaimiri is interpreted as an arboreal quadruped with frequent leaping across arboreal gaps, as in extant Saimiri, with perhaps less frequent running and leaping than in Saimiri. As with the dentition, the postcranial specimens suggest the close relationship between Neosaimiri and extant Saimiri. Am J Phys Anthropol 102:515–544, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
272.
The immature stages of Pangaeus (Pangaeus) serripes are described for the first time. Immature stages are illustrated and notes about their biology are included. Morphological features of the legs of the nymphs are associated with the fossorial habit of the Cydninae. Both adults and nymphs have been reared and found feeding on fallen fruits and seeds of several species of figs in Mexico.  相似文献   
273.
A new fossil penguin skeleton from the La Meseta Formation collected at the locality DPV 13/84 (Seymour Island, Antarctic Peninsula) from the crinoid horizon located 40 m above the base of the 145 m-thick Submeseta Allomember (Late Eocene–Early Oligocene?) is described. The specimen is assigned to the species Palaeeudyptes klekowskii Myrcha, Tatur and del Valle, 1990; it is the most complete penguin skeleton ever recovered from Antarctica. Discoveries like this one are significant for the study of the anatomy and evolution of penguins, in particular regarding the Antarctic species included in the genus Palaeeudyptes Huxley, 1859. P. klekowskii closely resembles its smaller congeneric species P. gunnari ( Wiman, 1905), with only the relative concavity of the margo medialis distinguishing the tarsometatarsi of both taxa. However, the results of a geometric morphometric analysis show some intra- and inter-specific variations, making possible the systematic assignment of the majority of the specimens. Size variation is congruent with the presence of two different species.  相似文献   
274.
275.
The effect of the cold pressor test on plasma DBH activity in ten healthy human subjects was investigated. Parallel changes of other plasma constituents were ascertained as well. Plasma DBH activity rose by over ten per cent in six of the sen subjects and declined by 14 per cent or more in two subjects; the correlations of altertions in DBH activity with changes of high molecular weight plasma constituents were high (r=0.565 to 0.902); correlations with blood urea nitrogen and plasma glucose were low (r=0.002 to 0.248). The results suggest that factors other than neuronal DBH release may be important in alterations of plasma DBH activity following acute stresses produced by the cold pressor test in man.  相似文献   
276.
277.
Abstract We report the effects of El Niño-Southern Oscillation (ENSO) events on the distribution and abundance of 3 raptor species at continental, regional, and landscape scales. We correlated values from the southern oscillation index (SOI), an index of ENSO phase and strength, with Christmas Bird Count data over a 30-year period. We investigated the relationship between the SOI and winter raptor distributions at 3 spatial scales: continental (central United States), regional (TX, USA), and landscape (3 roadside transects within TX). At the continental scale, ENSO events resulted in regional shifts for American kestrel (Falco sparverius), northern harrier (Circus cyaneus), and red-tailed hawk (Buteo jamaicensis) winter abundances. As expected, these shifts were northward during El Niño (warm) winters, and southward for red-tailed hawks and northern harriers during La Niña (cold) winters. Within Texas, northern harrier distributions shifted towards arid west Texas during wet El Niño winters but were restricted to mesic coastal Texas during dry La Niña winters. Red-tailed hawk abundance increased in eastern Texas during La Niña winters responding to cooler than normal temperatures throughout the northern Midwest. Data from local roadside transects over a 3-year period encompassing 2 El Niño winters and one La Niña winter supported the abundance patterns revealed by continental and regional data, and added evidence that fluctuations in winter abundances result from demographic pulses as well as spatial shifts for wintering populations. This study underscores the need for long-term monitoring at both local and regional spatial scales in order to detect changes in continental populations. Short-term or local studies would have erroneously assumed local population declines or increases associated with ENSO events, rather than facultative movements or demographic pulses supported by this study.  相似文献   
278.
Over the last decade, the cult of La Santa Muerte (St Death) has attracted a remarkable number of followers in Mexico and the USA. Whereas the social context of her devotees, who tend to live on the fringes of society, has attracted ample attention from scholars and journalists, one of the principal puzzles is still how a skeleton image of death has come to be seen as a saint by large numbers of Catholics. How is it possible for this figure to embrace such antagonistic qualities as death and sainthood in a Christian context? In this semiotic-material exploration of the image's genealogy, I suggest that La Santa Muerte should be seen as a coalescing of two radically distinct images of death: the popular-secular Catrina and the occult-biblical Santísima Muerte. The St Death venerated today encompasses the ambiguities of the two and creates an exceptionally vibrant and popular Catholic image.  相似文献   
279.
新疆洛浦山普拉古墓人骨的种系问题   总被引:4,自引:4,他引:0  
新疆洛浦山普拉古墓地的古代居民在体质形态特点上应是接近长颅欧洲人种地中海东支类型而不是具有“大蒙古人种大部分特征,但也有欧罗巴人种一些较明显特征”的混血类型。  相似文献   
280.
The isolated rabbit sperm plasma membrane autoantigen RSA-1 has been identified as a receptor for the lectin, Ricinus communis I (RCA). Using purified RSA-1 labeled with125 I, the autoantigen was shown to bind to RCA affinity columns and the eluted fraction bound to specific anti-RSA-1 alloantiserum immunoadsorbent columns.  相似文献   
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