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51.
Tsuji N Kasuga-Aoki H Isobe T Yoshihara S 《International journal for parasitology》2000,30(2):125-128
Antioxidant enzymes in parasites play an important role in protection against the oxygen radicals by generating during aerobic metabolism, as well as in defence against host immune cell assault. Here we report the cloning and characterisation of a cDNA encoding peroxiredoxin from Ascaris suum (AsPrx). AsPrx is 776bp long and contains the nematode 22bp splice leader sequence at the 5' end and polyadenylation signal followed by poly(A) tail at the 3' end. AsPrx codes a full-length protein with a predicted molecular mass of 22. 6kDa, and possesses two cysteine residues at amino acid 49 and 168 that are conserved among Prx proteins. GenBank() analysis showed that the deduced amino acid sequence had significant similarity to parasite and mammalian Prx at the amino acid level. DNA nicking revealed that Escherichia coli-expressed recombinant AsPrx (rAsPrx) is enzymatically inhibited to form oxidative-nicking of supercoiled plasmid DNA. Two-dimensional immunoblot analysis with mouse anti-rAsPrx serum reacted two major constituent protein spots in extracts of adult female worms, suggesting that the native AsPrx might be function as a major antioxidant enzyme in Ascaris suum. 相似文献
52.
Tian L Nyman H Kilgannon P Yoshihara Y Mori K Andersson LC Kaukinen S Rauvala H Gallatin WM Gahmberg CG 《The Journal of cell biology》2000,150(1):243-252
Intercellular adhesion molecule-5 (ICAM-5) is a dendritically polarized membrane glycoprotein in telencephalic neurons, which shows heterophilic binding to leukocyte beta(2)-integrins. Here, we show that the human ICAM-5 protein interacts in a homophilic manner through the binding of the immunoglobulin domain 1 to domains 4-5. Surface coated ICAM-5-Fc promoted dendritic outgrowth and arborization of ICAM- 5-expressing hippocampal neurons. During dendritogenesis in developing rat brain, ICAM-5 was in monomer form, whereas in mature neurons it migrated as a high molecular weight complex. The findings indicate that its homophilic binding activity was regulated by nonmonomer/monomer transition. Thus, ICAM-5 displays two types of adhesion activity, homophilic binding between neurons and heterophilic binding between neurons and leukocytes. 相似文献
53.
Chiellini G Nguyen NH Yoshihara HA Scanlan TS 《Bioorganic & medicinal chemistry letters》2000,10(23):2607-2611
Synthesis of the TRbeta-selective thyromimetic GC-1 has been improved using methoxymethyl (MOM) and triisopropylsilyl (TiPS) substituents as phenolic protecting groups. The new synthetic route is adaptable to analogue design. 相似文献
54.
Chen X Haruma K Kamada T Mihara M Komoto K Yoshihara M Sumii K Kajiyama G 《Helicobacter》2000,5(2):98-103
Background. The 13 C urea breath test (UBT) is considered to be the most accurate way of diagnosing Helicobacter pylori infection. Our objective was to investigate the accuracy of the UBT in Japanese patients and the association of UBT values with histological findings.
Materials and Methods. A total of 169 consecutive patients were studied by endoscopy with histology, by serology with IgG antibody and test serum pepsinogen (PG), and by UBT. The association between UBT values and histological findings and the PG I / II ratio were analyzed in H. pylori –positive patients.
Results. Of 169 Japanese patients, 135 were H. pylori –positive on both histology and serology analysis, 27 were H. pylori –negative on both histology and serology analysis, and 7 patients showed differing results. Using a cutoff value of 2.5‰, test sensitivity was 100%, while specificity was 96%. Among the 135 H. pylori –positive patients, a significant relation was observed between UBT value and H. pylori colonization density of the corpus and antrum, neutrophil activity of the antrum, atrophy, and intestinal metaplasia of the corpus in the H. pylori –positive patients. Also, UBT values correlated with the PG I /II ratio. In multivariate analysis, the PG I /II ratio was the most important factor related to UBT values (odds ration [OR], 4.99; 95% confidence interval, 1.60–15.55).
Conclusions. The UBT is an accurate method for detecting H. pylori infection in the Japanese population, which shows a high prevalence of atrophic gastritis. Values are affected by H. pylori infection and by the severity of atrophic gastritis. 相似文献
Materials and Methods. A total of 169 consecutive patients were studied by endoscopy with histology, by serology with IgG antibody and test serum pepsinogen (PG), and by UBT. The association between UBT values and histological findings and the PG I / II ratio were analyzed in H. pylori –positive patients.
Results. Of 169 Japanese patients, 135 were H. pylori –positive on both histology and serology analysis, 27 were H. pylori –negative on both histology and serology analysis, and 7 patients showed differing results. Using a cutoff value of 2.5‰, test sensitivity was 100%, while specificity was 96%. Among the 135 H. pylori –positive patients, a significant relation was observed between UBT value and H. pylori colonization density of the corpus and antrum, neutrophil activity of the antrum, atrophy, and intestinal metaplasia of the corpus in the H. pylori –positive patients. Also, UBT values correlated with the PG I /II ratio. In multivariate analysis, the PG I /II ratio was the most important factor related to UBT values (odds ration [OR], 4.99; 95% confidence interval, 1.60–15.55).
Conclusions. The UBT is an accurate method for detecting H. pylori infection in the Japanese population, which shows a high prevalence of atrophic gastritis. Values are affected by H. pylori infection and by the severity of atrophic gastritis. 相似文献
55.
Synechocystis: sp. PCC 6803 is a unicellular motile cyanobacterium, which shows positive or negative phototaxis on agar plates under lateral illumination. By gene disruption in a substrain showing of positive phototaxis, it was demonstrated that mutants defective in sll0038, sll0039, sll0041, sll0042 or sll0043 lost positive phototaxis but showed negative phototaxis away from the light source. Mutants of sll0040, which is located within the cluster of these genes, retained the capacity of positive phototaxis but to a lesser extent than the parent cells. These genes are homologous to che genes, which are involved in flagellar switching for bacterial chemotaxis. Interestingly, sll0041 (designated pisJ1) is predicted to have a chromophore-binding motif of phytochrome-like proteins and a signaling motif of chemoreceptors for bacterial chemotaxis. It is strongly suggested that the positive phototactic response was mediated by a phytochrome-like photoreceptor and CheA/CheY-type signal transduction system. 相似文献
56.
High iron-content transgenic tobacco plants have been produced by transfer via Agrobacterium tumefaciens of soyabean ferritin cDNA under the control of a CaMV 35S promoter. Immunoblot analysis of protein from transgenic tobacco plants suggested mature ferritin subunits are produced by cleavage of transit peptides. The expressed ferritin was observed in the tissues of leaves and stems. The maximal iron content of transformant leaves was approximately 30% higher than leaves from non-transformants. The increased iron content of each transformant was correlated with increases in ferritin content. These results demonstrate the potential of breeding high iron content crops by introduction of the ferritin gene 相似文献
57.
58.
Masahito Yoshihara Hiroko Ohmiya Susumu Hara Satoshi Kawasaki FANTOM consortium Yoshihide Hayashizaki Masayoshi Itoh Hideya Kawaji Motokazu Tsujikawa Kohji Nishida 《PloS one》2015,10(3)
The corneal endothelium is a monolayer of hexagonal corneal endothelial cells (CECs) on the inner surface of the cornea. CECs are critical in maintaining corneal transparency through their barrier and pump functions. CECs in vivo have a limited capacity in proliferation, and loss of a significant number of CECs results in corneal edema called bullous keratopathy which can lead to severe visual loss. Corneal transplantation is the most effective method to treat corneal endothelial dysfunction, where it suffers from donor shortage. Therefore, regeneration of CECs from other cell types attracts increasing interests, and specific markers of CECs are crucial to identify actual CECs. However, the currently used markers are far from satisfactory because of their non-specific expression in other cell types. Here, we explored molecular markers to discriminate CECs from other cell types in the human body by integrating the published RNA-seq data of CECs and the FANTOM5 atlas representing diverse range of cell types based on expression patterns. We identified five genes, CLRN1, MRGPRX3, HTR1D, GRIP1 and ZP4 as novel markers of CECs, and the specificities of these genes were successfully confirmed by independent experiments at both the RNA and protein levels. Notably none of them have been documented in the context of CEC function. These markers could be useful for the purification of actual CECs, and also available for the evaluation of the products derived from other cell types. Our results demonstrate an effective approach to identify molecular markers for CECs and open the door for the regeneration of CECs in vitro. 相似文献
59.
Naoya Yoshihara Taiji Sakamoto Takehiro Yamashita Toshifumi Yamashita Keita Yamakiri Shozo Sonoda Tatsuro Ishibashi 《PloS one》2015,10(4)