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81.
82.
Zsolt Végvári Edit Juhász János Pál Tóth Zoltán Barta Sándor Boldogh Sándor Szabó Zoltán Varga 《Oikos》2015,124(2):235-242
Emergence phenology has been shown to advance considerably in the past decades in many lepidopterans. Noctuid moths (Noctuidae) constitute a species‐rich family of lepidopterans with a large diversity of life history traits presumably driving climatic responsiveness. In our study we aim to assess the role of life‐history and ecological traits in climatic responsiveness of noctuid moths, whilst controlling for phylogenetic dependence. We used a long‐term dataset of European noctuid moths collected from a light‐trap in northeastern Hungary. As the study site is located at the intersection of several biogeographical zones harbouring a large number of noctuid moth species, our dataset provides a unique possibility to investigate the moths’ climatic sensitivity. To estimate the role of life‐history traits and ecological factors in driving lepidopterans’ response to climatic trends, we employed three proxies related to the species’ ecology (habitat affinity, food plant specialization and food type) and two robust types of life‐history traits (migration strategy and hibernation form). The degree of temporal shifts of various measures of emergence phenology was related to hibernation stage, food type and migration strategy. Large‐scale phylogenetic relatedness exerted little constraint in all models fitted on each measure of phenology. Our results imply that noctuid moths overwintering as adults exhibited greater degrees of phenological shifts than species hibernating as larvae or pupae. It implies that moths hibernating as adults are forced to suspend activity in our climate and the prolongation of autumn activity might be the result of increased plasticity in flight periods. 相似文献
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84.
Intraspecific variability in root colonization, extraradical growth pattern, and survival after cold storage of Lactarius deliciosus isolates was determined in pure culture conditions using Pinus pinaster as a host plant. The ectomycorrhizal ability of L. deliciosus at 30, 45, and 60 days from inoculation was highly variable among isolates and was negatively correlated to the age of the
culture (time elapsed from isolation). The formation of rhizomorphs was related to colonization ability, but no relationship
was found between colonization and formation of extraradical mycelium. The final colonization achieved at 60 days from inoculation
was not related to the tree species under which the sporocarps were collected. However, isolates from sporocarps collected
under P. pinaster colonized more rapidly the seedlings than those collected under other pine species. The climatic range of the sporocarps
from which the isolates were obtained (maritime vs. continental) was not related to the formation of mycorrhizas at 60 days
from inoculation. However, isolates from sporocarps collected from a maritime climate area colonized more rapidly the P. pinaster seedlings than those collected from a continental zone. Tolerance to cold water storage of L. deliciosus was also isolate dependent. Growth revival in agar was obtained from most of the isolates after 28 months of cold storage
at 4°C, but only 10 out of 29 isolates showed unaffected growth. The ITS rDNA alignment of all the L. deliciosus isolates showed a low variability with identities over 99%. Most of the variation was detected in the ITS1 region and consisted
in single nucleotide changes and/or punctual indel mutations. The number of base differences per sequence from averaging over
all sequence pairs was 1.329, which is in the low range when compared with other ectomycorrhizal species. No ITS pattern due
to geographical origin of the isolates could be discerned. 相似文献
85.
Wang GZ Haile PA Daniel T Belot B Viet AQ Goodman KB Sha D Dowdell SE Varga N Hong X Chakravorty S Webb C Cornejo C Olzinski A Bernard R Evans C Emmons A Briand J Chung CW Quek R Lee D Gough PJ Sehon CA 《Bioorganic & medicinal chemistry letters》2011,21(24):7291-7294
A series of biarylsulfonamides was identified as hCCR2 receptor antagonist but suffered from high plasma protein binding resulting in a >100 fold shift in activity in a functional GTPγS assay run in tandem in the presence and absence of human serum albumin. Introduction of an aryl amide with ethylenediamine linker led to compounds with reduced shifts and improved activity in whole blood. 相似文献
86.
Schmolke M Manicassamy B Pena L Sutton T Hai R Varga ZT Hale BG Steel J Pérez DR García-Sastre A 《PLoS pathogens》2011,7(8):e1002186
Highly pathogenic avian influenza A viruses (HPAIV) of the H5N1 subtype occasionally transmit from birds to humans and can cause severe systemic infections in both hosts. PB1-F2 is an alternative translation product of the viral PB1 segment that was initially characterized as a pro-apoptotic mitochondrial viral pathogenicity factor. A full-length PB1-F2 has been present in all human influenza pandemic virus isolates of the 20(th) century, but appears to be lost evolutionarily over time as the new virus establishes itself and circulates in the human host. In contrast, the open reading frame (ORF) for PB1-F2 is exceptionally well-conserved in avian influenza virus isolates. Here we perform a comparative study to show for the first time that PB1-F2 is a pathogenicity determinant for HPAIV (A/Viet Nam/1203/2004, VN1203 (H5N1)) in both mammals and birds. In a mammalian host, the rare N66S polymorphism in PB1-F2 that was previously described to be associated with high lethality of the 1918 influenza A virus showed increased replication and virulence of a recombinant VN1203 H5N1 virus, while deletion of the entire PB1-F2 ORF had negligible effects. Interestingly, the N66S substituted virus efficiently invades the CNS and replicates in the brain of Mx+/+ mice. In ducks deletion of PB1-F2 clearly resulted in delayed onset of clinical symptoms and systemic spreading of virus, while variations at position 66 played only a minor role in pathogenesis. These data implicate PB1-F2 as an important pathogenicity factor in ducks independent of sequence variations at position 66. Our data could explain why PB1-F2 is conserved in avian influenza virus isolates and only impacts pathogenicity in mammals when containing certain amino acid motifs such as the rare N66S polymorphism. 相似文献
87.
Judit Kocsis Tamás Mészáros Balázs Madaras Éva Katalin Tóth Szilárd Kamondi Péter Gál Lilian Varga Zoltán Prohászka George Füst 《Cell stress & chaperones》2011,16(1):49-55
Recently, we reported that high soluble Hsp70 (sHsp70) level was a significant predictor of mortality during an almost 3-year-long
follow-up period in patients with colorectal cancer. This association was the strongest in the group of <70-year-old female
patients as well as in those who were in a less advanced stage of the disease at baseline. According to these observations,
measurement of the serum level of sHsp70 is a useful, stage-independent prognostic marker in colorectal cancer, especially
in patients without distant metastasis. Since many literature data indicated that measurement of C-reactive protein (CRP)
and other acute phase proteins (APPs) may also be suitable for predicting the mortality of patients with colorectal cancer,
it seemed reasonable to study whether the effect of sHsp70 and other APPs are related or independent. In order to answer this
question, we measured the concentrations of CRP as well as of other complement-related APPs (C1 inhibitor, C3, and C9) along
with that of the MASP-2 complement component in the sera of 175 patients with colorectal cancer and known levels of sHsp70,
which have been used in our previous study. High (above median) levels of CRP, C1 esterase inhibitor (C1-INH), and sHsp70
were found to be independently associated with poor patient survival, whereas no such association was observed with the other
proteins tested. According to the adjusted Cox proportional hazards analysis, the additive effect of high sHsp70, CRP, and
C1-INH levels on the survival of patients exceeded that of high sHsp70 alone, with a hazard ratio (HR) of 2.83 (1.13–70.9).
In some subgroups of patients, such as in females [HR 4.80 (1.07–21.60)] or in ≤70-year-old patients [HR 11.53 (2.78–47.70)],
even greater differences were obtained. These findings indicate that the clinical mortality–prediction value of combined measurements
of sHsp70, CRP, and C1-INH with inexpensive methods can be very high, especially in specific subgroups of patients with colorectal
cancer. 相似文献
88.
89.
The effects of di-(2-ethylhexyl)-phthalate (DEPH) on the levels of cytochrome P-450 and b5 monooxygenases were studied in the rat kidney and liver in acute renal failure induced by glycerol. Intramuscular injection of glycerol (50%,10 ml x kg(-1)) to rats produced proximal tubular damage and acute renal failure. The indicators of renal function, serum urea and creatinine significantly increased (480 and 350 percent, respectively). In control and glycerol-treated animals DEPH had no significant effect on the concentrations of serum urea and creatinine. Twenty-four hours after glycerol injection the total amount of cytochrome P-450 and b5 significantly decreased in renal but increased in liver microsomal fractions. Moreover, 48 and 72 hours after glycerol injection the level of cytochrome P-450 and b5 significantly increased in both organs. A single dose of DEPH (2 ml x kg(-1), i.p.) also elevated the total cytochrome P-450 and b5 in control animals. This enhancing effect of DEPH was additive to that of glycerol in glycerol-induced acute renal failure. These results indicate that DEPH and glycerol evoked pathological changes may affect the metabolism of xenobiotics plus endogenous hormones in the liver and in kidney. 相似文献
90.
Simultaneous video-microfluorimetry allows experimenters to monitor calcium signals in the cytosol, as well as changes in the membrane potential of the mitochondria, in living cells loaded with both fura2 and rhodamine123 (rhod123). Capsaicin-evoked responses of cultured sensory neurons and transfected HT1080 cells are described below. Polymodal nociceptors [1] or other cells expressing TRPV1 receptors respond to capsaicin application with a rise in the cytosolic calcium level ([Ca2+]c), reaching eventually toxic levels. Capsaicin induces selective permanent morphological changes of the mitochondria before any loss of small cells (type B) in the sensory ganglia can be detected [3]. An unknown link between changes in the mitochondria and cell loss can be investigated by combined functional examination of capsaicin-induced [Ca2+]c changes and reactions of the mitochondria. In most tests, the capsaicin-induced [Ca2+]c elevation occurred before the rising phase of rhod123 waves. Cellular reactions were either transient or sustained (lasting over hundreds of seconds). A transient or a sustained nature of the reactions was slightly concentration-dependent. Fluorescence of the cells changed in complicated ways during repeated tests. Moderate but permanent changes of the cellular responsiveness suggest mild injury, which might be involved in cellular desensitization.Neirofiziologiya/Neurophysiology, Vol. 37, No. 1, pp. 82–93, January–February, 2005. 相似文献