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921.
922.
Etsushi Kitamura Kozo Tanaka Shinya Komoto Yoko Kitamura Claude Antony Tomoyuki U. Tanaka 《Developmental cell》2010,18(2):248-259
Highlights? A short-lived population of kinetochore-derived microtubules (MTs) has distal plus ends ? These MTs are generated in early mitosis and regulated by Stu2 ? They interact with spindle pole-derived MTs before kinetochore attachment ? Once kinetochores attach to spindle-pole MTs, the short-lived MT population disappears 相似文献
923.
Umeda T Takashima N Nakagawa R Maekawa M Ikegami S Yoshikawa T Kobayashi K Okanoya K Inokuchi K Osumi N 《PloS one》2010,5(12):e15500
Autism is a highly variable brain developmental disorder and has a strong genetic basis. Pax6 is a pivotal player in brain development and maintenance. It is expressed in embryonic and adult neural stem cells, in astrocytes in the entire central nervous system, and in neurons in the olfactory bulb, amygdala, thalamus, and cerebellum, functioning in highly context-dependent manners. We have recently reported that Pax6 heterozygous mutant (rSey(2)/+) rats with a spontaneous mutation in the Pax6 gene, show impaired prepulse inhibition (PPI). In the present study, we further examined behaviors of rSey(2)/+ rats and revealed that they exhibited abnormality in social interaction (more aggression and withdrawal) in addition to impairment in rearing activity and in fear-conditioned memory. Ultrasonic vocalization (USV) in rSey(2)+ rat pups was normal in male but abnormal in female. Moreover, treatment with clozapine successfully recovered the defects in sensorimotor gating function, but not in fear-conditioned memory. Taken together with our prior human genetic data and results in other literatures, rSey(2)/+ rats likely have some phenotypic components of autism. 相似文献
924.
In this study we examined the effect of ribbon-type (circular-type) NF-kappaB decoy oligodeoxynucleotides (RNODN) on osteoclast induction and activity. We extracted bone marrow cells from the femurs of rats and incubated non-adherent cells with receptor activator of nuclear factor kappaB ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). First, transfer efficiency into osteoclasts and their precursors, resistance to exonuclease, and binding activity of decoy to NF-kappaB were examined. Next, to examine the effect of RNODN on osteoclast induction and activity, osteoclast differentiation and pit formation assays were performed. RNODN were injected into the ankle joints of rats with collagen-induced arthritis. Joint destruction and osteoclast activity were examined by histological study. The resistance of RNODN to exonuclease and their binding activity on NF-kappaB were both greater than those of phosphorothionated NF-kappaB decoy oligodeoxynucleotides. The absolute number of multinucleate cells scoring positive for tartrate-resistant acid phosphatase was significantly decreased in the RNODN-treated group. The average calcified matrix resorbed area was significantly decreased in the RNODN-treated group. Histological study showed marked suppression of joint destruction and osteoclast activity by intra-articular injection of RNODN. These results suggest the inhibitory effect of RNODN on the induction and activity of osteoclasts. Direct intra-articular injection of RNODN into the joints may be an effective strategy for the treatment of arthritis. 相似文献
925.
926.
Shinya Uno Daisuke Kodama Hiroko Yukawa Hiroyuki Shidara Miki Akamatsu 《Journal of peptide science》2020,26(3)
Peptides from enzymatic hydrolysates of food proteins exhibit significant antioxidant activity. Several studies have attempted to determine the factors contributing to the antioxidant activity of peptides; however, the physicochemical properties and factors essential for the antioxidant activity of peptides are still unclear. In this study, in order to clarify the factors important for peptide antioxidant activity based on the properties of component amino acids, 55 tripeptides were synthesized from 20 natural amino acids and their antioxidant activity was measured using the Trolox equivalent antioxidant capacity (TEAC) assay system. The tripeptides were divided into two data sets: a training set comprising 50 compounds and a validated set comprising five compounds. The structure‐activity relationship of the training set was then analyzed using classical quantitative structure‐activity relationship (QSAR) analysis. The study findings demonstrate that the presence of a cysteine residue at any position, an aromatic amino acid at the C‐terminus, higher hydrophobicity of the N‐terminal residue, and smaller HOMO‐LUMO energy gap of the middle residue can significantly enhance the antioxidant activity. The activities of the five validated compounds were predicted using the constructed QSAR model, and a good correlation between measured and predicted activities was observed. The information obtained from the QSAR model could be useful for effective production of antioxidant peptides from food proteins such as egg white proteins. 相似文献
927.
Food Biophysics - The naturally occurring soybean pectin–protein conjugate pre-adsorbed to the air–water interface was shown to be displaced competitively from the interface when a... 相似文献
928.
Leo Y Lee Jie Zhou Paulina Koszalka Rebecca Frise Rubaiyea Farrukee Keiko Baba Shahjahan Miah Takao Shishido Monica Galiano Takashi Hashimoto Shinya Omoto Takeki Uehara Edin J. Mifsud Neil Collinson Klaus Kuhlbusch Barry Clinch Steffen Wildum Wendy S. Barclay Aeron C. Hurt 《PLoS pathogens》2021,17(5)
Baloxavir is approved in several countries for the treatment of uncomplicated influenza in otherwise-healthy and high-risk patients. Treatment-emergent viruses with reduced susceptibility to baloxavir have been detected in clinical trials, but the likelihood of widespread occurrence depends on replication capacity and onward transmission. We evaluated the fitness of A/H3N2 and A/H1N1pdm09 viruses with the polymerase acidic (PA) I38T-variant conferring reduced susceptibility to baloxavir relative to wild-type (WT) viruses, using a competitive mixture ferret model, recombinant viruses and patient-derived virus isolates. The A/H3N2 PA/I38T virus showed a reduction in within-host fitness but comparable between-host fitness to the WT virus, while the A/H1N1pdm09 PA/I38T virus had broadly similar within-host fitness but substantially lower between-host fitness. Although PA/I38T viruses replicate and transmit between ferrets, our data suggest that viruses with this amino acid substitution have lower fitness relative to WT and this relative fitness cost was greater in A/H1N1pdm09 viruses than in A/H3N2 viruses. 相似文献
929.
Effect of glucocorticoid on glycosaminoglycans synthesis in cultured mouse embryonic palatal mesenchymal cells 总被引:1,自引:0,他引:1
H Yoshikawa H Tashiro K Kurisu 《Journal of craniofacial genetics and developmental biology》1986,6(3):235-244
The effect of glucocorticoids (GC) on the synthesis of glycosaminoglycans (GAGs) in mesenchymal cells obtained from palatal shelves of mouse embryos was studied. Both hyaluronic acid (HA) synthesis and sulfated GAG synthesis were inhibited with triamcinolone acetonide (TA) in a concentration-dependent manner. However, the degree of inhibition of synthesis with TA was greater for HA than for the sulfated GAGs. To determine whether the inhibitory effects of TA on HA and sulfated GAGs synthesis were mediated through GC receptors, we performed experiments using progesterone, vitamin B6, and molybdate. The inhibitory effect of TA was antagonized by all three. The results obtained in the present study suggest that the inhibition of synthesis of HA and sulfated GAGs with GC is mediated through GC receptors and is involved in cleft palate induction by GC. 相似文献
930.
Yanagita M Kobayashi R Kashiwagi Y Shimabukuro Y Murakami S 《Biochemical and biophysical research communications》2007,364(2):318-324
Thrombin is the key enzyme in the coagulation cascade and activates endothelial cells, neutrophils and monocytes via protease-activated receptors (PARs). At the inflammatory site, immune cells have an opportunity to encounter thrombin. However little is known about the effect of thrombin for dendritic cells (DC), which are efficient antigen-presenting cells and play important roles in initiating and regulating immune responses. The present study revealed that thrombin has the ability to stimulate blood DC. Plasmacytoid DC (PDC) and myeloid DC (MDC) isolated from PBMC expressed PAR-1 and released MCP-1, IL-10, and IL-12 after thrombin stimulation. Unlike blood DC, monocyte-derived DC (MoDC), differentiated in vitro did not express PAR-1 and were unresponsive to thrombin. Effects of thrombin on blood DC were significantly diminished by the addition of anti-PAR-1 Ab or hirudin, serine protease inhibitor. Moreover, thrombin induced HLA-DR and CD86 expression on DC and the thrombin-treated DC induced allogenic T cell proliferation. These findings indicate that thrombin plays a role in the regulation of blood DC functions. 相似文献