全文获取类型
收费全文 | 750篇 |
免费 | 70篇 |
专业分类
820篇 |
出版年
2022年 | 6篇 |
2021年 | 9篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 10篇 |
2017年 | 14篇 |
2016年 | 8篇 |
2015年 | 16篇 |
2014年 | 24篇 |
2013年 | 42篇 |
2012年 | 29篇 |
2011年 | 43篇 |
2010年 | 19篇 |
2009年 | 26篇 |
2008年 | 47篇 |
2007年 | 36篇 |
2006年 | 29篇 |
2005年 | 26篇 |
2004年 | 18篇 |
2003年 | 33篇 |
2002年 | 29篇 |
2001年 | 36篇 |
2000年 | 37篇 |
1999年 | 30篇 |
1998年 | 9篇 |
1997年 | 4篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1994年 | 11篇 |
1993年 | 11篇 |
1992年 | 14篇 |
1991年 | 25篇 |
1990年 | 15篇 |
1989年 | 18篇 |
1988年 | 12篇 |
1987年 | 16篇 |
1986年 | 12篇 |
1985年 | 11篇 |
1984年 | 13篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1980年 | 10篇 |
1979年 | 8篇 |
1977年 | 3篇 |
1975年 | 5篇 |
1967年 | 3篇 |
1966年 | 2篇 |
1965年 | 2篇 |
1956年 | 3篇 |
1937年 | 2篇 |
排序方式: 共有820条查询结果,搜索用时 15 毫秒
101.
Akimoto-Tomiyama C Furutani A Tsuge S Washington EJ Nishizawa Y Minami E Ochiai H 《Molecular plant-microbe interactions : MPMI》2012,25(4):505-514
Xanthomonas oryzae pv. oryzae is the causal agent of bacterial blight of rice. The XopR protein, secreted into plant cells through the type III secretion apparatus, is widely conserved in xanthomonads and is predicted to play important roles in bacterial pathogenicity. Here, we examined the function of XopR by constructing transgenic Arabidopsis thaliana plants expressing it under control of the dexamethasone (DEX)-inducible promoter. In the transgenic plants treated with DEX, slightly delayed growth and variegation on leaves were observed. Induction of four microbe-associated molecular pattern (MAMP)-specific early-defense genes by a nonpathogenic X. campestris pv. campestris hrcC deletion mutant were strongly suppressed in the XopR-expressing plants. XopR expression also reduced the deposition of callose, an immune response induced by flg22. When transiently expressed in Nicotiana benthamiana, a XopR::Citrine fusion gene product localized to the plasma membrane. The deletion of XopR in X. oryzae pv. oryzae resulted in reduced pathogenicity on host rice plants. Collectively, these results suggest that XopR inhibits basal defense responses in plants rapidly after MAMP recognition. 相似文献
102.
Nishizawa T Tago K Oshima K Hattori M Ishii S Otsuka S Senoo K 《Journal of bacteriology》2012,194(5):1255
We report the finished and annotated genome sequence of a denitrifying and N(2)O-reducing betaproteobacterium, Azoarcus sp. strain KH32C. The genome is composed of one chromosome and one megaplasmid and contains genes for plant-microbe interactions and the gene clusters for aromatic-compound degradations. 相似文献
103.
104.
Taiji Asami Naoki Nishizawa Yoshihiro Ishibashi Kimiko Nishibori Masaharu Nakayama Yasuko Horikoshi Shin-ichi Matsumoto Masashi Yamaguchi Hirokazu Matsumoto Naoki Tarui Tetsuya Ohtaki Chieko Kitada 《Bioorganic & medicinal chemistry letters》2012,22(20):6391-6396
Metastin/kisspeptin, a 54-amino acid peptide, is the ligand of the G-protein-coupled receptor KISS1R which plays a key role in pathways that regulate reproduction and cell migration in many endocrine and gonadal tissues. The N-terminally truncated decapeptide, metastin(45–54), has 3–10 times higher receptor affinity and intracellular calcium ion-mobilizing activity but is rapidly inactivated in serum. In this study we designed and synthesized stable KISS1R agonistic decapeptide analogs with selected substitutions at positions 47, 50, and 51. Replacement of glycine with azaglycine (azaGly) in which the α-carbon is replaced with a nitrogen atom at position 51 improved the stability of amide bonds between Phe50-Gly51 and Gly51-Leu52 as determined by in vitro mouse serum stability studies. Substitution for tryptophan at position 47 with other amino acids such as serine, threonine, β-(3-pyridyl)alanine, and d-tryptophan (d-Trp), produced analogs that were highly stable in mouse serum. d-Trp47 analog 13 showed not only high metabolic stability but also excellent KISS1R agonistic activity. Other labile peptides may have increased serum stability using amino acid substitution. 相似文献
105.
Y Fujishima N Maeda K Inoue S Kashine H Nishizawa A Hirata J Kozawa T Yasuda K Okita A Imagawa T Funahashi I Shimomura 《Cardiovascular diabetology》2012,11(1):107-8
ABSTRACT: BACKGROUND: We recently reported that short-term treatment with liraglutide (20.0 +/- 6.4 days) reduced body weight and improved some scales of eating behavior in Japanese type 2 diabetes inpatients. However, it remained uncertain whether such liraglutide-induced improvement is maintained after discharge from the hospital. The aim of the present study was to determine the long-term effects of liraglutide on body weight, glycemic control, and eating behavior in Japanese obese type 2 diabetics. METHODS: Patients with obesity (body mass index (BMI) >25 kg/m2) and type 2 diabetes were hospitalized at Osaka University Hospital between November 2010 and December 2011. BMI and glycated hemoglobin (HbA1c) were examined on admission, at discharge and at 1, 3, and 6 months after discharge. For the liraglutide group (BMI; 31.3 +/- 5.3 kg/m2, n = 29), patients were introduced to liraglutide after correction of hyperglycemic by insulin or oral glucose-lowering drugs and maintained on liraglutide after discharge. Eating behavior was assessed in patients treated with liraglutide using The Guideline For Obesity questionnaire issued by the Japan Society for the Study of Obesity, at admission, discharge, 3 and 6 months after discharge. For the insulin group (BMI; 29.1 +/- 3.0 kg/m2, n = 28), each patient was treated with insulin during hospitalization and glycemic control maintained by insulin after discharge. RESULTS: Liraglutide induced significant and persistent weight loss from admission up to 6 months after discharge, while no change in body weight after discharge was noted in the insulin group. Liraglutide produced significant improvements in all major scores of eating behavior questionnaire items and such effect was maintained at 6 months after discharge. Weight loss correlated significantly with the decrease in scores for recognition of weight and constitution, sense of hunger, and eating style. CONCLUSION: Liraglutide produced meaningful long-term weight loss and significantly improved eating behavior in obese Japanese patients with type 2 diabetes. 相似文献
106.
Colostomy is conventionally the only treatment for anal dysfunction. Recently, a few trials of anorectal transplantation in animals have been published; however, further development of this technique is required. Moreover, it is crucial to perform this research in dogs, which resemble humans in anorectal anatomy and biology. We designed a canine anorectal transplantation model, wherein anorectal autotransplantation was performed by anastomoses of the rectum, inferior mesenteric artery (IMA) and vein, and pudendal nerves. Resting pressure in the anal canal and anal canal pressure fluctuation were measured before and after surgery. Graft pathology was examined three days after surgery. The anal blood supply was compared with that in three beagles using indocyanine green (ICG) fluorescence angiography. The anorectal graft had sufficient arterial blood supply from the IMA; however, the graft's distal end was congested and necrotized. Functional examination demonstrated reduced resting pressure and the appearance of an irregular anal canal pressure wave after surgery. ICG angiography showed that the pudendal arteries provided more blood flow than the IMA to the anal segment. This is the first canine model of preliminary anorectal autotransplantation, and it demonstrates the possibility of establishing a transplantation model in dogs using appropriate vascular anastomoses, thus contributing to the progress of anorectal transplantation. 相似文献
107.
108.
Ryuichi Takahashi Khurram Bashir Yasuhiro Ishimaru Naoko K. Nishizawa Hiromi Nakanishi 《Plant signaling & behavior》2012,7(12):1605-1607
The P1B-type heavy metal ATPases (HMAs) are diverse in terms of tissue distribution, subcellular localization, and metal specificity. Functional studies of HMAs have shown that these transporters can be divided into two subgroups based on their metal-substrate specificity: a copper (Cu)/silver (Ag) group and a zinc (Zn)/cobalt (Co)/cadmium (Cd)/lead (Pb) group. Studies on Arabidopsis thaliana and metal hyperaccumulator plants indicate that HMAs play an important role in the translocation or detoxification of Zn and Cd in plants. Rice possesses nine HMA genes, of which OsHMA1–OsHMA3 belong to the Zn/Co/Cd/Pb subgroup. OsHMA2 plays an important role in root-to-shoot translocation of Zn and Cd, and participates in Zn and Cd transport to developing seeds in rice. OsHMA3 transports Cd and plays a role in the sequestration of Cd into vacuoles in root cells. Modification of the expression of these genes might be an effective approach for reducing the Cd concentration in rice grains. 相似文献
109.
Takashi Fujikawa Ayumu Sakaguchi Yoko Nishizawa Yusuke Kouzai Eiichi Minami Shigekazu Yano Hironori Koga Tetsuo Meshi Marie Nishimura 《PLoS pathogens》2012,8(8)
Plants evoke innate immunity against microbial challenges upon recognition of pathogen-associated molecular patterns (PAMPs), such as fungal cell wall chitin. Nevertheless, pathogens may circumvent the host PAMP-triggered immunity. We previously reported that the ascomycete Magnaporthe oryzae, a famine-causing rice pathogen, masks cell wall surfaces with α-1,3-glucan during invasion. Here, we show that the surface α-1,3-glucan is indispensable for the successful infection of the fungus by interfering with the plant''s defense mechanisms. The α-1,3-glucan synthase gene MgAGS1 was not essential for infectious structure development but was required for infection in M. oryzae. Lack or degradation of surface α-1,3-glucan increased fungal susceptibility towards chitinase, suggesting the protective role of α-1,3-glucan against plants'' antifungal enzymes during infection. Furthermore, rice plants secreting bacterial α-1,3-glucanase (AGL-rice) showed strong resistance not only to M. oryzae but also to the phylogenetically distant ascomycete Cochlioborus miyabeanus and the polyphagous basidiomycete Rhizoctonia solani; the histocytochemical analysis of the latter two revealed that α-1,3-glucan also concealed cell wall chitin in an infection-specific manner. Treatment with α-1,3-glucanase in vitro caused fragmentation of infectious hyphae in R. solani but not in M. oryzae or C. miyabeanus, indicating that α-1,3-glucan is also involved in maintaining infectious structures in some fungi. Importantly, rapid defense responses were evoked (a few hours after inoculation) in the AGL-rice inoculated with M. oryzae, C. miyabeanus and R. solani as well as in non-transgenic rice inoculated with the ags1 mutant. Taken together, our results suggest that α-1,3-glucan protected the fungal cell wall from degradative enzymes secreted by plants even from the pre-penetration stage and interfered with the release of PAMPs to delay innate immune defense responses. Because α-1,3-glucan is nondegradable in plants, it is reasonable that many fungal plant pathogens utilize α-1,3-glucan in the innate immune evasion mechanism and some in maintaining the structures. 相似文献
110.
Oda M Matsuno T Shiihara R Ochi S Yamauchi R Saito Y Imagawa H Nagahama M Nishizawa M Sakurai J 《Journal of lipid research》2008,49(5):1039-1047
Clostridium perfringens alpha-toxin induces the hemolysis of sheep erythrocytes by activating the metabolism of sphingomyelin (SM) via a GTP binding protein in membranes. alpha-Toxin stimulated the formation of 15-N-nervonoyl sphingosine (C24:1-ceramide), which was identified by positive ion fast atom bombardment-MS and 1H-NMR spectroscopy. C24:1-ceramide stimulated the toxin-induced hemolysis of saponin-pretreated sheep erythrocytes and increased the production of sphingosine 1-phosphate (S1P) in the cells, but N-lignoceroyl sphingosine did not. These events elicited by the toxin in the presence of C24:1-ceramide were significantly attenuated by treatment with dihydrosphingosine, a sphingosine kinase inhibitor. TLC showed that the level of C24:1-ceramide was highest among the ceramides with an unsaturated bond in the fatty acyl chain in the detergent-resistant membranes (DRMs). The toxin specifically bound to DRMs rich in cholesterol, resulting in the hydrolysis of N-nervonoic sphingomyelin (C24:1-SM) in DRMs. Treatment of the cells with pertussis toxin (PT) inhibited the alpha-toxin-induced formation of C24:1-ceramide from C24:1-SM in DRMs and hemolysis, indicating that endogenous sphingomyelinase, which hydrolyzes C24:1-SM to C24:1-ceramide, is controlled by PT-sensitive GTP binding protein in membranes. These results show that the toxin-induced metabolism of C24:1-SM to S1P in DRMs plays an important role in the toxin-induced hemolysis of sheep erythrocytes. 相似文献