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101.
The Latemar is a mainly aggrading platform, but shows repeated backstepping during its entire development. The behaviour of the slope does not reflect accommodation changes and lateral consistencies of the lagoonal interior; the Latemar contemporaneously reveals different, even contrasting depositional characteristics. The slope of the late stage platform evolution corresponds at least partially to the base-of-slope apron model. Controlling factors on slope evolution are of tectonic (proximity of the Stava Line) and autocyclic (repeated oversteepening) nature. Other factors are insignificant and/or overprinted. The reef-facies at Latemar reveals a complex facies pattern; it varies along and across the margin and is rich in encrusting sponges, corals, biogenic crusts and Microproblematica. Some biota or fossil assemblages—e.g. foraminifers (Abriolina mediterranea, Turriglomina scandonei) or Tubiphytes multisiphonatus thrombolites—have not been described in the Dolomites before. Biostratigraphic evidence from the uppermost reef-facies confirms a mainly Anisian age of the outcropping platform interior. 相似文献
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104.
桂西和黔南中三叠世珊瑚 总被引:1,自引:0,他引:1
文内描述中三叠世安尼阶(Anisian)珊瑚化石分别采自桂西田阳板纳组和黔南贵阳青岩青岩组。板纳组珊瑚群中建立Pentasmilia guangxiensisgen.etsp.nov.,该新属种有5条第一周期原生隔片甚至有5条第二周期后生隔片,以此不同于有6条第一周期原生隔片和有6条第二周期后生隔片的石珊瑚类(scleractinians)的珊瑚。产于板纳组的另一新属种Radiophyllia astylatusgen.etsp.nov.,其隔片的排列格式与前人归纳的隔片周期插入示意图甚似,但它却发生在中生代最早期(Anisian)珊瑚的骸体内。文中还对青岩组的Pamiroseris silesiaca作了重新描述。 相似文献
105.
Oryctocephalid trilobites from Lower Middle Cambrian strata of the eastern Anti-Atlas, Morocco, are the first described Oryctocephalidae known from Africa. They represent the new genus and species Shergoldiella vincenti. However, a similar species was earlier described as Tonkinella sequei Liñán et Gozalo, 1999, from coeval lower Middle Cambrian strata of the Iberian Chains, northern Spain. This Iberian species is imperfectly preserved and assigned herein to Shergoldiella with reservations. If this assignment is correct, it would reinforce earlier suggested correlations between Morocco and Spain. Nevertheless, Shergoldiella suggests a morphocline from a typical oryctocephalid-type morphology towards the Tonkinella-type morphology. Close similarity with Ovatoryctocara ovata suggests a similar stratigraphic position in accordance with earlier suggested intercontinental correlations. 相似文献
106.
JAIME LIRA† ANNA LINDERHOLM‡ CARMEN OLARIA§ MIKAEL BRANDSTRÖM DURLING¶ M. THOMAS P. GILBERT HANS ELLEGREN†† ESKE WILLERSLEV KERSTIN LIDÉN‡ JUAN LUIS ARSUAGA† ANDERS GÖTHERSTRÖM†† 《Molecular ecology》2010,19(1):64-78
Multiple geographical regions have been proposed for the domestication of Equus caballus . It has been suggested, based on zooarchaeological and genetic analyses that wild horses from the Iberian Peninsula were involved in the process, and the overrepresentation of mitochondrial D1 cluster in modern Iberian horses supports this suggestion. To test this hypothesis, we analysed mitochondrial DNA from 22 ancient Iberian horse remains belonging to the Neolithic, the Bronze Age and the Middle Ages, against previously published sequences. Only the medieval Iberian sequence appeared in the D1 group. Neolithic and Bronze Age sequences grouped in other clusters, one of which (Lusitano group C) is exclusively represented by modern horses of Iberian origin. Moreover, Bronze Age Iberian sequences displayed the lowest nucleotide diversity values when compared with modern horses, ancient wild horses and other ancient domesticates using nonparametric bootstrapping analyses. We conclude that the excessive clustering of Bronze Age horses in the Lusitano group C, the observed nucleotide diversity and the local continuity from wild Neolithic Iberian to modern Iberian horses, could be explained by the use of local wild mares during an early Iberian domestication or restocking event, whereas the D1 group probably was introduced into Iberia in later historical times. 相似文献
107.
Kristof Haneca Ilse Boeren Joris Van Acker Hans Beeckman 《Vegetation History and Archaeobotany》2006,15(2):137-144
Throughout the Middle Ages forests in Flanders (northern Belgium) experienced a dramatic human influence. Forests were logged
for wood supply and converted to arable land. The structure of the remaining forests was altered. This, combined with the
tempering influence of the Atlantic climate, results in conditions that are suboptimal for dendrochronological research. Tree-ring
series of Quercus robur and Q. petraea of timber from medieval archaeological sites are often short, show abrupt growth-rate variations and are complacent. The
question arises whether tree-ring series of this type are potential records of past management and whether they could constitute
the basis of a reference chronology for archaeological dating. During six archaeological excavations in and around the medieval
town of Ypres, cross-sections were collected. The tree-ring series could be dated back to the 12th–14th centuries, using reference
chronologies from surrounding regions. The growth pattern of the short sequences displays a high similarity to tree-ring series
from modern coppice. For the first time, it has been confirmed that dendrochronological analysis in Flanders is possible and
can provide valuable information on medieval forest use and structure. 相似文献
108.
Matthew J. Mason Sarah J. Lucas Erica R. Wise Robin S. Stein Melinda J. Duer 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2006,192(12):1349-1357
The densities of middle ear ossicles of golden moles (family Chrysochloridae, order Afrosoricida) were measured using the
buoyancy method. The internal structure of the malleus was examined by high-resolution computed tomography, and solid-state
NMR was used to determine relative phosphorus content. The malleus density of the desert golden mole Eremitalpa granti (2.44 g/cm3) was found to be higher than that reported in the literature for any other terrestrial mammal, whereas the ossicles of other
golden mole species are not unusually dense. The increased density in Eremitalpa mallei is apparently related both to a relative paucity of internal vascularization and to a high level of mineralization.
This high density is expected to augment inertial bone conduction, used for the detection of seismic vibrations, while limiting
the skull modifications needed to accommodate the disproportionately large malleus. The mallei of the two subspecies of E. granti, E. g. granti and E. g. namibensis, were found to differ considerably from one another in both size and shape. 相似文献
109.
U. B. Willi G. N. Bronner P. M. Narins 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2006,192(3):267-277
Comparison between the middle ear anatomy of the Cape golden mole (Chrysochloris asiatica), which exhibits a club-shaped malleus head, and the Desert golden mole (Eremitalpa granti), with a ball-shaped malleus head, suggests differences in sensitivity to airborne sound. Scanning laser Doppler vibrometric
measurements of the ossicular behavior in response to both vibration and airborne sound were made in C. asiatica. Two distinct vibrational modes were observed. In response to low-frequency vibration (70–200 Hz), the malleus oscillates
about the ligament of the short process of the incus, whereas in response to high-frequency airborne sound (1–6 kHz) the ossicular
chain rotates about the long axis of malleus. It is proposed that the club-shaped malleus head in C. asiatica constitutes an adaptation towards bimodal hearing—sensitivity to substrate vibrations and airborne sound. Possible functional
differences between these two middle ear types are discussed. 相似文献
110.
Four new ambocoeliid species, Ambocoelia ectypa sp. nov., Echinocoelia tikhiensis sp. nov., Emanuella takwanensis (Kayser), and Ladjia sita sp. nov., from the Givetian of the southern Verkhoyansk Region are described (northeastern Russia). 相似文献