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61.
Motoyuki Nakamura Yorihiko Koeda Fumitaka Tanaka Toshiyuki Onoda Kazuyoshi Itai Masaki Ohsawa Kozo Tanno Kiyomi Sakata Shinich Omama Yasuhiro Ishibashi Shinji Makita Mutsuko Ohta Kuniaki Ogasawara Takashi Komatsu Akira Okayama 《PloS one》2013,8(12)
Objectives
Atrial fibrillation (AF) is a significant public health issue due to its high prevalence in the general population, and is associated with an increased risk of cardiovascular (CV) events including systemic thrombo-embolism, heart failure, and coronary artery disease. The relationship between plasma B-type natriuretic peptide (BNP) and CV risk in real world AF subjects remains unknown.Methods
The subject of the study (n = 228; mean age = 69 years) was unselected individuals with AF in a community-based population (n = 15,394; AF prevalence rate = 1.5%). The CV event free rate within each BNP tertile was estimated, and Cox regression analysis was performed to examine the relative risk of the onset of CV events among the tertiles. The prognostic ability of BNP was compared to an established risk score for embolic events (CHADS2 score). In addition, to determine the usefulness of BNP as a predictor in addition to CHADS2 score, we calculated Net Reclassification Improvement (NRI) and Integrated Discrimination Improvement (IDI) indices.Results
During the follow-up period 58 subjects experienced CV events (52 per 1,000 person-years). The event-free ratio was significantly lower in the highest tertile (p < 0.02). After adjustment for established CV risk factors, the hazard ratio (HR) of the highest tertile was significantly higher than that of the lowest tertile (HR = 2.38; p < 0.02). The predictive abilities of plasma BNP in terms of sensitivity and specificity for general CV events were comparable to those of CHADS2 score. Adding BNP to the CHADS2 score only model improved the NRI (0.319; p < 0.05) and the IDI (0.046; p < 0.05).Conclusion
Plasma BNP is a valuable biomarker both singly or in combination with an established scoring system for assessing general CV risk including stroke, heart failure and acute coronary syndrome in real-world AF subjects. 相似文献62.
63.
Michele Carbone Erin G. Flores Mitsuru Emi Todd A. Johnson Tatsuhiko Tsunoda Dusty Behner Harriet Hoffman Mary Hesdorffer Masaki Nasu Andrea Napolitano Amy Powers Michael Minaai Francine Baumann Peter Bryant-Greenwood Olivia Lauk Michaela B. Kirschner Walter Weder Isabelle Opitz Harvey I. Pass Giovanni Gaudino Sandra Pastorino Haining Yang 《PLoS genetics》2015,11(12)
We recently discovered an inherited cancer syndrome caused by BRCA1-Associated Protein 1 (BAP1) germline mutations, with high incidence of mesothelioma, uveal melanoma and other cancers and very high penetrance by age 55. To identify families with the BAP1 cancer syndrome, we screened patients with family histories of multiple mesotheliomas and melanomas and/or multiple cancers. We identified four families that shared an identical BAP1 mutation: they lived across the US and did not appear to be related. By combining family histories, molecular genetics, and genealogical approaches, we uncovered a BAP1 cancer syndrome kindred of ~80,000 descendants with a core of 106 individuals, whose members descend from a couple born in Germany in the early 1700s who immigrated to North America. Their descendants spread throughout the country with mutation carriers affected by multiple malignancies. Our data show that, once a proband is identified, extended analyses of these kindreds, using genomic and genealogical studies to identify the most recent common ancestor, allow investigators to uncover additional branches of the family that may carry BAP1 mutations. Using this knowledge, we have identified new branches of this family carrying BAP1 mutations. We have also implemented early-detection strategies that help identify cancers at early-stage, when they can be cured (melanomas) or are more susceptible to therapy (MM and other malignancies). 相似文献
64.
65.
For the first step toward resolution of the higher-level relationships of the order Aulopiformes (Teleostei: Eurypterygii)
using longer DNA sequences, we determined the complete mitochondrial DNA sequence for Aulopus japonicus (Aulopodidae). The entire genome was purified by gene amplification using a long PCR technique, and the products were subsequently
used as templates for PCR with 63 fish-versatile and 3 species-specific primers that amplify contiguous, overlapping segments
of the entire genome. Direct sequencing of the PCR products demonstrated that the genome (16 653 base pairs [bp]) contained
the same 37 mitochondrial genes (2 ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes) as found in other vertebrates,
with the gene order identical to that in typical vertebrates. Maximum-parsimony analysis using nucleotide sequences from the
concatenated 12 protein-coding genes (no third codon positions and excluding the ND6 gene) plus 22 tRNA genes (stem regions
only) from eight teleosts placed A. japonicus in a reasonable phylogenetic position; those from individual protein-coding genes and the concatenated 22 tRNA genes alone,
however, did not reproduce the expected phylogeny with few exceptions, probably owing to insufficient phylogenetic information
in these smaller data sets. This result suggests that further taxonomic sampling and sequencing efforts may clarify limits
and intra- and interrelationships of this morphologically and ecologically diverse group of fishes using mitochondrial genomic
(mitogenomic) data.
Received: August 31, 2000 / Revised: December 20, 2000 / Accepted: January 23, 2001 相似文献
66.
Kataoka R Siddiqui ZA Kikuchi J Ando M Sriwati R Nozaki A Futai K 《Journal of microbiology (Seoul, Korea)》2012,50(2):199-206
The fungus Tricholoma matsutake forms an ectomycorrhizal relationship with pine trees. Its sporocarps often develop in a circle, which is commonly known
as a fairy ring. The fungus produces a solid, compact, white aggregate of mycelia and mycorrhizae beneath the fairy ring,
which in Japanese is called a ’shiro’. In the present study, we used soil dilution plating and molecular techniques to analyze
the bacterial communities within, beneath, and outside the T. matsutake fairy ring. Soil dilution plating confirmed previous reports that bacteria and actinomycetes are seldom present in the soil
of the active mycorrhizal zone of the T. matsutake shiro. In addition, the results showed that the absence of bacteria was strongly correlated with the presence of T. matsutake mycorrhizae. The results demonstrate that bacteria, especially aerobic and heterotrophic forms, and actinomycetes, are strongly
inhibited by T. matsutake. Indeed, neither bacteria nor actinomycetes were detected in 11.3% of 213 soil samples from the entire shiro area by culture-dependent
methods. However, molecular techniques demonstrated that some bacteria, such as individual genera of Sphingomonas and Acidobacterium, were present in the active mycorrhizal zone, even though they were not detected in soil assays using the dilution plating
technique. 相似文献
67.
Kim J Hirasawa T Saito M Furusawa C Shimizu H 《Applied microbiology and biotechnology》2011,91(1):143-151
Glutamate overproduction by Corynebacterium glutamicum is triggered by treatment with penicillin or Tween 40 and is accompanied by a decrease in 2-oxoglutarate dehydrogenase complex
(ODHC) activity. We have reported that de novo synthesis of OdhI, which inhibits ODHC activity by interacting specifically
with the E1o subunit of ODHC (OdhA), is induced by penicillin, and that odhI overexpression induces glutamate overproduction in the absence of any triggers for glutamate overproduction. In this study,
to determine the function of OdhI in glutamate overproduction by C. glutamicum, changes in OdhI levels and phosphorylation status during penicillin- and Tween 40-induced glutamate overproduction were
examined by western blot. The synthesis of both unphosphorylated and phosphorylated OdhI was increased by addition of Tween
40 or penicillin and the levels of unphosphorylated OdhI, which can inhibit ODHC activity, was significantly higher than those
of phosphorylated OdhI, which is unable to inhibit ODHC activity. Meanwhile, the OdhA levels were maintained throughout the
culture. These results indicate that OdhI synthesis is induced by additions of penicillin and Tween 40 and most synthesized
OdhI is unphosphorylated, resulting in the decrease in ODHC activity and glutamate overproduction. Similarly, in the odhI-overexpressing strain, both unphosphorylated and phosphorylated OdhI were synthesized, while the levels of OdhA were nearly
constant throughout culture. Our results suggest that high level of unphosphorylated OdhI regulates glutamate overproduction
by C. glutamicum. 相似文献
68.
Molecular basis of guanine nucleotide dissociation inhibitor activity of human neuroglobin by chemical cross-linking and mass spectrometry 总被引:1,自引:0,他引:1
Kitatsuji C Kurogochi M Nishimura S Ishimori K Wakasugi K 《Journal of molecular biology》2007,368(1):150-160
Oxidized human neuroglobin (Ngb), a heme protein expressed in the brain, has been proposed to act as a guanine nucleotide dissociation inhibitor (GDI) for the GDP-bound form of the heterotrimeric G protein alpha-subunit (Galpha(i)). Here, to elucidate the molecular mechanism underlying the GDI activity of Ngb, we used an glutathione-S-transferase pull-down assay to confirm that Ngb competes with G-protein betagamma-subunits (Gbetagamma) for binding to Galpha(i), and identified the Galpha(i)-binding site in Ngb by chemical cross-linking with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride and sulfo-N-hydroxysuccinimide, coupled with mass spectrometry (MS). Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS analysis for tryptic peptides derived from the cross-linked Ngb-Galpha(i) complex revealed several binding regions in Ngb. Furthermore, MALDI-TOF/TOF MS analysis of the cross-linked Ngb and Galpha(i) peptides, together with the MS/MS scoring method, predicted cross-linking between Glu60 (Ngb) and Ser206 (Galpha(i)), and between Glu53 (Ngb) and Ser44 (Galpha(i)). Because Ser206 of Galpha(i) is located in the region that contacts Gbetagamma, binding of Ngb could facilitate the release of Gbetagamma from Galpha(i). Binding of Ngb to Galpha(i) would also inhibit the exchange of GDP for GTP, because Ser44 (Galpha(i)) is adjacent to the GDP-binding site and Glu53 (Ngb), which is cross-linked to Ser44 (Galpha(i)), could be located close to GDP. Thus, we have identified, for the first time, the sites of interaction between Ngb and Galpha(i), enabling us to discuss the functional significance of this binding on the GDI activity of Ngb. 相似文献
69.
Hamatani T Sasaki H Ishihara K Hida N Maruyama T Yoshimura Y Hata J Umezawa A 《Biochimica et biophysica acta》2001,1518(1-2):137-144
We have investigated the epigenetic mark in the human H19 gene. The H19 promoter is methylation-free in human sperm, but it is methylated in the paternally derived allele of most adult tissues. Consequently, the H19 gene is exclusively transcribed from the maternal allele. It was demonstrated that the differentially methylated region (DMR) located 2 kb upstream from mouse H19 is essential for the imprinting of H19. A 39 bp sequence in DMR has a high degree of similarity between humans, mice and rats. The highly conserved 15 bp core region of the consensus sequence contains four methylatable sites, and thus has been proposed as a potential imprinting mark region. In this study, fine epigenetic sequencing analysis was performed on the sperm DNA in comparison with other adult organs. Interestingly, the conserved sequence of the potential mark region was methylated in almost all the sperm genomes analyzed. Furthermore, the single dinucleotide CpG, whose methylation affects the accessibility of the element to CTCF, was methylated in the conserved core in the human sperm. These results suggest that the human core sequences may act as an imprinting center in the reciprocal monoallelic expression of H19. 相似文献
70.
E Katayama T Wakabayashi F Reinach T Masaki D A Fischman 《Journal of biochemistry》1984,95(3):721-727
MF-18, one of the monoclonal antibodies generated to chicken myosin, cross-reacted with rabbit skeletal myosin subfragment-1 (S1). Utilizing an improved procedure of immuno-blotting, a decrease in reactivity of MF-18 to S1 by trinitrophenylation was observed. This indicates that the reactive lysyl residue is very close to the hapten site. This is consistent with the evidence that the hapten site resides in the 26,000 dalton tryptic fragment of S1. Use of such antibodies as labels may open the way to determining the location of specific hapten sites in the three-dimensional image of actin-S1 complex reconstructed from the electron micrographs. 相似文献