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941.
Tuberosciponoceras insolitum n. gen., n. sp. is a single dimorphic species in the Upper Albian of the Austrat Basin, southern Patagonia. The short-lived
genus was characterized by distinct ventral tubercles on all ribs and a deep, trifid internal lobe. 相似文献
942.
Cinzia Comino Sergio Lanteri Ezio Portis Alberto Acquadro Annalisa Romani Alain Hehn Romain Larbat Frédéric Bourgaud 《BMC plant biology》2007,7(1):14
Background
Cynara cardunculus L. is an edible plant of pharmaceutical interest, in particular with respect to the polyphenolic content of its leaves. It includes three taxa: globe artichoke, cultivated cardoon, and wild cardoon. The dominating phenolics are the di-caffeoylquinic acids (such as cynarin), which are largely restricted to Cynara species, along with their precursor, chlorogenic acid (CGA). The scope of this study is to better understand CGA synthesis in this plant. 相似文献943.
Balhorn R 《Genome biology》2007,8(9):227
The protamines are a diverse family of small arginine-rich proteins that are synthesized in the late-stage spermatids of many
animals and plants and bind to DNA, condensing the spermatid genome into a genetically inactive state. Vertebrates have from
one to 15 protamine genes per haploid genome, which are clustered together on the same chromosome. Comparison of protamine
gene and amino-acid sequences suggests that the family evolved from specialized histones through protamine-like proteins to
the true protamines. Structural elements present in all true protamines are a series of arginine-rich DNA-anchoring domains
(often containing a mixture of arginine and lysine residues in non-mammalian protamines) and multiple phosphorylation sites.
The two protamines found in mammals, P1 and P2, are the most widely studied. P1 packages sperm DNA in all mammals, whereas
protamine P2 is present only in the sperm of primates, many rodents and a subset of other placental mammals. P2, but not P1,
is synthesized as a precursor that undergoes proteolytic processing after binding to DNA and also binds a zinc atom, the function
of which is not known. P1 and P2 are phosphorylated soon after their synthesis, but after binding to DNA most of the phosphate
groups are removed and cysteine residues are oxidized, forming disulfide bridges that link the protamines together. Both P1
and P2 have been shown to be required for normal sperm function in primates and many rodents. 相似文献
944.
945.
Background
The need for discovery of alternative, renewable, environmentally friendly energy sources and the development of cost-efficient, "clean" methods for their conversion into higher fuels becomes imperative. Ethanol, whose significance as fuel has dramatically increased in the last decade, can be produced from hexoses and pentoses through microbial fermentation. Importantly, plant biomass, if appropriately and effectively decomposed, is a potential inexpensive and highly renewable source of the hexose and pentose mixture. Recently, the engineered (to also catabolize pentoses) anaerobic bacterium Zymomonas mobilis has been widely discussed among the most promising microorganisms for the microbial production of ethanol fuel. However, Z. mobilis genome having been fully sequenced in 2005, there is still a small number of published studies of its in vivo physiology and limited use of the metabolic engineering experimental and computational toolboxes to understand its metabolic pathway interconnectivity and regulation towards the optimization of its hexose and pentose fermentation into ethanol. 相似文献946.
Debra L Fisk Leigh C LattaIV Roland A Knapp Michael E Pfrender 《BMC evolutionary biology》2007,7(1):22
Background
Introduced species can have profound effects on native species, communities, and ecosystems, and have caused extinctions or declines in native species globally. We examined the evolutionary response of native zooplankton populations to the introduction of non-native salmonids in alpine lakes in the Sierra Nevada of California, USA. We compared morphological and life-history traits in populations of Daphnia with a known history of introduced salmonids and populations that have no history of salmonid introductions. 相似文献947.
The effect of abatacept, a selective T-cell co-stimulation modulator, on vaccination has not been previously investigated.
In this open-label, single-dose, randomized, parallel-group, controlled study, the effect of a single 750 mg infusion of abatacept
on the antibody response to the intramuscular tetanus toxoid vaccine (primarily a memory response to a T-cell-dependent peptide
antigen) and the intramuscular 23-valent pneumococcal vaccine (a less T-cell-dependent response to a polysaccharide antigen)
was measured in 80 normal healthy volunteers. Subjects were uniformly randomized to receive one of four treatments: Group
A (control group), subjects received vaccines on day 1 only; Group B, subjects received vaccines 2 weeks before abatacept;
Group C, subjects received vaccines 2 weeks after abatacept; and Group D, subjects received vaccines 8 weeks after abatacept.
Anti-tetanus and anti-pneumococcal (Danish serotypes 2, 6B, 8, 9V, 14, 19F and 23F) antibody titers were measured 14 and 28
days after vaccination. While there were no statistically significant differences between the dosing groups, geometric mean
titers following tetanus or pneumococcal vaccination were generally lower in subjects who were vaccinated 2 weeks after receiving
abatacept, compared with control subjects. A positive response (defined as a twofold increase in antibody titer from baseline)
to tetanus vaccination at 28 days was seen, however, in ≥ 60% of subjects across all treatment groups versus 75% of control
subjects. Similarly, over 70% of abatacept-treated subjects versus all control subjects (100%) responded to at least three
pneumococcal serotypes, and approximately 25–30% of abatacept-treated subjects versus 45% of control subjects responded to
at least six serotypes. 相似文献
948.
Background
Enzymes involved in DNA metabolic events of the highly radioresistant bacterium Deinococcus radiodurans are currently examined to understand the mechanisms that protect and repair the Deinococcus radiodurans genome after extremely high doses of γ-irradiation. Although several Deinococcus radiodurans DNA repair enzymes have been characterised, no biochemical data is available for DNA ligation and DNA endhealing enzymes of Deinococcus radiodurans so far. DNA ligases are necessary to seal broken DNA backbones during replication, repair and recombination. In addition, ionizing radiation frequently leaves DNA strand-breaks that are not feasible for ligation and thus require end-healing by a 5'-polynucleotide kinase or a 3'-phosphatase. We expect that DNA ligases and end-processing enzymes play an important role in Deinococcus radiodurans DNA strand-break repair. 相似文献949.
The objective of this study was to determine the prevalence, mutual associations, clinical manifestations, and diagnoses associated
with serum autoantibodies, as detected using recently available immunoassays, in patients with autoimmune myositis (AIM).
Sera and clinical data were collected from 100 patients with AIM followed longitudinally. Sera were screened cross-sectionally
for 21 autoantibodies by multiplex addressable laser bead immunoassay, line blot immunoassay, immunoprecipitation of in vitro translated recombinant protein, protein A assisted immunoprecipitation, and enzyme-linked immunosorbent assay. Diagnoses
were determined using the Bohan and Peter classification as well as recently proposed classifications. Relationships between
autoantibodies and clinical manifestations were analyzed by multiple logistic regression. One or more autoantibodies encompassing
19 specificities were present in 80% of the patients. The most common autoantibodies were anti-Ro52 (30% of patients), anti-Ku
(23%), anti-synthetases (22%), anti-U1RNP (15%), and anti-fibrillarin (14%). In the presence of autoantibodies to Ku, synthetases,
U1RNP, fibrillarin, PM-Scl, or scleroderma autoantigens, at least one more autoantibody was detected in the majority of sera
and at least two more autoantibodies in over one-third of sera. The largest number of concurrent autoantibodies was six autoantibodies.
Overall, 44 distinct combinations of autoantibodies were counted. Most autoantibodies were unrestricted to any AIM diagnostic
category. Distinct clinical syndromes and therapeutic responses were associated with anti-Jo-1, anti-fibrillarin, anti-U1RNP,
anti-Ro, anti-Ro52, and autoantibodies to scleroderma autoantigens. We conclude that a significant proportion of AIM patients
are characterized by complex associations of autoantibodies. Certain myositis autoantibodies are markers for distinct overlap
syndromes and predict therapeutic outcomes. The ultimate clinical features, disease course, and response to therapy in a given
AIM patient may be linked to the particular set of associated autoantibodies. These results provide a rationale for patient
profiling and its application to therapeutics, because it cannot be assumed that the B-cell response is the same even in the
majority of patients in a given diagnostic category. 相似文献
950.
Cédric MessaoudiI Thomas Boudier Carlos Oscar Sanchez Sorzano Sergio Marco 《BMC bioinformatics》2007,8(1):288