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81.
《Revista espa?ola de geriatría y gerontología》2016,51(3):159-163
The prevalence of neuropathic pain is difficult to estimate as most studies evaluating chronic pain do not differentiate neuropathic from nociceptive pain. There are only a few studies of neuropathic pain in the elderly, specifically in the oncology population. This article is a non-systematic review of the relevant evidence on the prevalence and aetiopathogenesis of neuropathic cancer pain in the elderly. 相似文献
82.
83.
Contrasting population changes in sympatric penguin species in association with climate warming 总被引:2,自引:0,他引:2
JAUME FORCADA P. N. TRATHAN K. REID E. J. MURPHY J. P. CROXALL 《Global Change Biology》2006,12(3):411-423
Climate warming and associated sea ice reductions in Antarctica have modified habitat conditions for some species. These include the congeneric Adélie, chinstrap and gentoo penguins, which now demonstrate remarkable population responses to regional warming. However, inconsistencies in the direction of population changes between species at different study sites complicate the understanding of causal processes. Here, we show that at the South Orkney Islands where the three species breed sympatrically, the less ice‐adapted gentoo penguins increased significantly in numbers over the last 26 years, whereas chinstrap and Adélie penguins both declined. These trends occurred in parallel with regional long‐term warming and significant reduction in sea ice extent. Periodical warm events, with teleconnections to the tropical Pacific, caused cycles in sea ice leading to reduced prey biomass, and simultaneous interannual population decreases in the three penguin species. With the loss of sea ice, Adélie penguins were less buffered against the environment, their numbers fluctuated greatly and their population response was strong and linear. Chinstrap penguins, considered to be better adapted to ice‐free conditions, were affected by discrete events of locally increased ice cover, but showed less variable, nonlinear responses to sea ice loss. Gentoo penguins were temporarily affected by negative anomalies in regional sea ice, but persistent sea ice reductions were likely to increase their available niche, which is likely to be substantially segregated from that of their more abundant congeners. Thus, the regional consequences of global climate perturbations on the sea ice phenology affect the marine ecosystem, with repercussions for penguin food supply and competition for resources. Ultimately, variability in penguin populations with warming reflects the local balance between penguin adaptation to ice conditions and trophic‐mediated changes cascading from global climate forcing. 相似文献
84.
Nicholas Shea 《Biology & philosophy》2007,22(3):313-331
There is ongoing controversy as to whether the genome is a representing system (Sterelny K., Smith K.C. and Dickson M. 1996.
Biol. Philos. 11: 377–403; Griffiths P.E. 2001. Philos. Sci. 68: 394–412). Although it is widely recognised that DNA carries
information, both correlating with and coding for various outcomes, neither of these implies that the genome has semantic
properties like correctness or satisfaction conditions (Godfrey-Smith P. 2002. In: Wolenski J. and Kajania-Placek K. (eds),
In the Scope of Logic, Methodology, and the Philosophy of Sciences, Vol. II. Kluwer, Dordrecht, pp. 387–400). Here a modified
version of teleosemantics is applied to the genome to show that it does indeed have semantic properties – there is representation
in the genome. The account differs in three respects from previous attempts to apply teleosemantics to genes. It emphasises
the role of the consumer of representations (in addition to their mode of production). It rejects the standard assumption
that genetic representation can be used to explain the course of an organism’s development. And it identifies the explanatory
role played by representational properties of the genome. A striking consequence of this account is that other inheritance
systems could also be representational. Thus, a version of the parity thesis is accepted (Griffiths P.E. 2001. Philos. Sci.
68: 394–412). However, the criteria for being an inheritance system are demanding, so semantic properties are not ubiquitous. 相似文献
85.
In the framework of the palaeogeographical reconstruction of the Western Taurus during Jurassic, the study of northern and eastern boundary of the Taurids started. Detailed facies analysis evidenced the position of the Barla Dag ramp between two elevated areas: the southern rimmed shelf extension of the platform system and the northern neritic-beach-land plain. In the basal biostratigraphical and ecological characteristics of the Balcikhisar volcano-sedimentary sequence, correlated with the Fele outcrop, one genus and three new species of foraminifers have been found: Sievoides kocyigiti n. gen., n. sp. and Mesoendothyra altineriana n. sp. from neritic environment, and Kurnubia feleensis n. sp. from rimmed shelf lagoon. Both carbonate sedimentary deposits are intercalated with spilitic-basalt pillow lava flows. The age of the new three species is Kimmeridgian, controlled by some foraminifer golden hooks. 相似文献
86.
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88.
《Bioorganic & medicinal chemistry》2016,24(2):294-303
New cyclic RGD peptide-anticancer agent conjugates, with different chemical functionalities attached to the parent peptide were synthesized in order to evaluate their biological activities and to provide a comparative study of their drug release profiles. The Integrin binding c(RGDfK) penta-peptide was used for the synthesis of Camptothecin (CPT) carbamate and Chlorambucil (CLB) amide conjugates. Substitution of the amino acid Lys with Ser resulted in a modified c(RGDfS) with a new attachment site, which enabled the synthesis of an ester CLB conjugate. Functional versatility of the conjugates was reflected in the variability of their drug release profiles, while the conserved RGD sequence of a selective binding to the αv integrin family, likely preserved their recognition by the Integrin and consequently their favorable toxicity towards targeted cancer cells. This hypothesis was supported by a computational analysis suggesting that all conjugates occupy conformational spaces similar to that of the Integrin bound bio-active parent peptide. 相似文献
89.
M.A. Mena M.J. Casarejos J.A. Rodríguez-Navarro I. Rodal J.G. de Yebenes 《FEBS letters》2009,583(1):168-174
Parkin mutations produce Parkinson’s disease (PD) in humans and nigrostriatal dopamine lesions related to increased free radicals in mice. We examined the effects of NP7, a synthetic, marine derived, free radical scavenger which enters the brain, on H2O2 toxicity in cultured neurons and glia from wild-type (WT) and parkin null mice (PK-KO).NP7, 5-10 μM, prevented the H2O2 induced apoptosis and necrosis of midbrain neuronal and glial cultures from WT and PK-KO mice. NP7 suppressed microglial activation and the H2O2 induced drop-out of dopamine neurons. Furthermore, NP7 prevented the increased phosphorylation of ERK and AKT induced by H2O2. NP7 may be a promising neuroprotector against oxidative stress in PD. 相似文献
90.
We isolated eight polymorphic microsatellites from the neotropical tree Luehea seemannii for gene flow and genetic structure studies. We used a streptavidin subtractive enrichment technique to develop a library of CA/GT repeats. Eight loci were screened for diversity from 96 individuals from Barro Colorado Island (BCI) and neighbouring Gigante peninsula in Panama. Luehea seemannii shows moderate levels of genetic diversity within these two populations. Allelic richness ranged from four to nine alleles and averaged 6.44 alleles per locus. Average expected heterozygosity was 0.65 on BCI and 0.60 on Gigante. Results are compared to microsatellite data from another wind‐dispersed gap colonizing species common in Panama. 相似文献