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911.
Wei DD Yuan ML Wang ZY Wang D Wang BJ Dou W Wang JJ 《Journal of economic entomology》2011,104(5):1720-1729
Psocids (Psocoptera: Liposcelididae: Liposcelis spp.) are major pests of stored grain and commonly occur on a wide range of stored products. Increasingly, the genus of Liposcelis has gained recognition of their importance due to their feeding on stored grains, contaminating food, and agricultural commodities as well as transmitting harmful microorganisms, including fungi and bacteria. Psocids have close morphological similarities and often commix occur at the same ecosystems. Therefore, a first step necessary to further implement population studies is the accurate identification of species, based on molecular methods. In this study, we determined nucleotide sequences of the nuclear rDNA internal transcribed spacer (ITS)1-5.8S-ITS2 region in 100 individuals of six Liposcelis species (including Liposcelis bostrychophila Badonnel, Liposcelis entomophila (Enderlein), Liposcelis decolor (Pearman), Liposcelis tricolor Badonnel, Liposcelis paeta Pearman, and Liposcelis yunnaniensis Li & Li) from 16 locations of China. We evaluated the suitability of this marker for phylogenetic inference study in the Liposcelis species. We also developed a molecular identification method for six Liposcelis species based on ITS2 sequence. Results demonstrate that ITS1-5.8S-ITS2 sequences are a useful tool for the population genetic study and phylogeny estimation of Liposcelis species. The results of this study indicate that the ITS2 sequences can be a reliable tool for species discrimination of the six species of psocids tested here. In addition, the multiplex method described proved reliable when tested across different geographical populations. 相似文献
912.
913.
Two host cytoplasmic effectors are required for pathogenesis of Phytophthora sojae by suppression of host defenses 总被引:2,自引:0,他引:2
Liu T Ye W Ru Y Yang X Gu B Tao K Lu S Dong S Zheng X Shan W Wang Y Dou D 《Plant physiology》2011,155(1):490-501
Phytophthora sojae encodes hundreds of putative host cytoplasmic effectors with conserved FLAK motifs following signal peptides, termed crinkling- and necrosis-inducing proteins (CRN) or Crinkler. Their functions and mechanisms in pathogenesis are mostly unknown. Here, we identify a group of five P. sojae-specific CRN-like genes with high levels of sequence similarity, of which three are putative pseudogenes. Functional analysis shows that the two functional genes encode proteins with predicted nuclear localization signals that induce contrasting responses when expressed in Nicotiana benthamiana and soybean (Glycine max). PsCRN63 induces cell death, while PsCRN115 suppresses cell death elicited by the P. sojae necrosis-inducing protein (PsojNIP) or PsCRN63. Expression of CRN fragments with deleted signal peptides and FLAK motifs demonstrates that the carboxyl-terminal portions of PsCRN63 or PsCRN115 are sufficient for their activities. However, the predicted nuclear localization signal is required for PsCRN63 to induce cell death but not for PsCRN115 to suppress cell death. Furthermore, silencing of the PsCRN63 and PsCRN115 genes in P. sojae stable transformants leads to a reduction of virulence on soybean. Intriguingly, the silenced transformants lose the ability to suppress host cell death and callose deposition on inoculated plants. These results suggest a role for CRN effectors in the suppression of host defense responses. 相似文献
914.
Tomco D Schmitt S Ksebati B Heeg MJ Dou QP Verani CN 《Journal of inorganic biochemistry》2011,105(12):1759-1766
In this paper we report on the synthesis and characterization of three cobalt complexes described as [CoII(L1)2] (1), [CoII(L2)] (2), and [CoIII(L1)2]ClO4(3). These complexes contain the deprotonated forms of the [NN′O] tridentate ligand HL1 and its newly synthesized [N2N′2O2] hexadentate counterpart H2L2, namely, 2,4-diiodo-6-((pyridine-2-ylmethylamino)methyl)phenol and 6,6′-((ethane-1,2-diylbis((pyridin-2-ylmethyl) azanediyl))bis(methylene))bis(2,4-diiodophenol). Characterizations for 1-3 include electrospray ionization (ESI) spectrometry, infrared, and UV-visible spectroscopies, and elemental analyses. A detailed 1H-NMR study was conducted for 3 and X-ray structural data was obtained for 2. The viability of this series as potential agents for proteasome inhibition and cell apoptotic induction involving PC-3 cancer cells is presented comparing the behavior of the untethered [NN′O]2 six-coordinate 1 and 3 and the tethered counterpart 2 with a 1:1 metal-to-ligand ratio. It is observed that the tethering in 2 decreases inhibition activity. When 1 and 3 are compared, the most inert, but redox-active, cobalt(III) species shows the highest chymotrypsin-like activity inhibition on purified proteasome and PC-3 cancer cells. A hypothesis based on the role of oxidation states for proteasome inhibition is offered. 相似文献
915.
Junrong T Huancheng Z Feng H Yi G Xiaoqin Y Zhengmao L Hong Z Jianying Z Yin W Yuanhang H Jianlin Z Longhua S Guolin H 《Journal of biosciences》2011,36(4):659-668
Hepatocellular carcinoma (HCC), among the most common malignancies worldwide, remains a major threat to public health, and there is an urgent need to identify novel biomarkers for diagnosis, prognosis and targets for anti-cancer treatment. In this study, two-dimensional polyacrylamide gel electrophoresis coupled with ESI-Q-TOF MS/MS analysis was used to identify differentially expressed proteins among the HCC tumour centre, tumour margin and nontumourous liver tissues. In total, 52 spots with significant alteration were positively identified byMS/MSanalysis. Altered expression of representative proteins, including CIB1, was validated by Western blotting. Immunostaining suggested an increase tendency of CIB1 expression from nontumourous liver tissue to tumour centre. Knockdown of CIB1 expression by RNA interference led to the significant suppression of the cell growth in hepatoma HepG2 cells. These data suggest that CIB1 may be used as a novel prognostic factor and possibly an attractive therapeutic target for HCC. 相似文献
916.
云南汉族人群5-羟色胺转运体基因启动子区多态性与酒精依赖的相关性 总被引:1,自引:0,他引:1
为了探讨云南汉族人群中5-羟色胺转运体基因启动子区多态性(5-HTTLPR)与酒精依赖的关联性, 文章采用PCR扩增和DNA测序技术, 对云南地区118例酒精依赖患者和214例健康对照个体进行了5-HTTLPR的基因多态性分析。结果表明: 酒精依赖患者组和正常对照组的5-HTTLPR的基因型分布存在显著性差异, L/L和L/S基因的携带者人群嗜酒发生率显著低于S/S基因型人群(OR: 0.581, P=0.026)。S和L等位基因频率在两组间无统计学差异(χ2=2.594, P=0.107), 但其分布存在种族差异性。因此, 云南地区人群中5-HTTLPR多态与酒精依赖存在相关性, L/L和L/S基因型可能是降低酒精依赖发病的影响因子之一。 相似文献
917.
A rare case with ectopic adrenocorticotrophic hormone syndrome (EAS) caused by medullar thyroid carcinoma (MTC) in mediastinum was reported. This 49 year-old male patient initially presented with serious and intractable hypokalemia. Endocrine evaluations showed increased levels of adrenocorticotrophic hormone (ACTH) and urinary free cortisol, which could not be suppressed more than 50% by high-dose dexamethasone suppression test. Computed tomography (CT) scan detected a 5×5×5?cm mass at the bottom of thyroid in anterior mediastinum. The patient underwent total thyroidectomy with central compartment and ipsilateral modified radical neck dissection. Pathological examination showed an infiltrating thyroid medullary carcinoma with abundant amyloid deposition, meanwhile immunohistochemical positive for ACTH. After surgery, serum levels of kalium, as well as cortisol and ACTH returned to normal range. During follow-up, the patient's clinical manifestation of Cushing syndrome relieved. 相似文献
918.
Background
Since it was initiated in 2002, the China Free Antiretroviral Treatment (ART) Program has been progressing from an emergency response to a standardized treatment and care system. As of December 31, 2009, a total of 81,880 patients in 31 provinces, autonomous regions, and special municipalities received free ART. Gender differences, however, in mortality and immunological response to ART in this cohort have never been described.Objective
To understand whether women and men who enrolled in the China National Free ART Program responded equally well to the treatment.Methods
A retrospective analysis of the national free ART databases from June 2006–December 2008 was performed. HIV-infected subjects who were 18 years or older, ART naïve at baseline, and on a 3TC regimen enrolled in the program from June 1 to December 31, 2006, were included in this study, then followed up to 2 years.Results
Among 3457 enrolled subjects who met the inclusion criteria, 59.2% were male and 40.8% female. The majority of the subjects were 19–44 years old (77%) and married (72%). Over the full 24 months of follow-up, the mortality rate was 19.0% in males and 11.4% in females (p = 0.0014). Males on therapy for 3–24 months were more likely to die than females (HR = 1.46, 95% CI: 1.04–2.06, p = 0.0307) after adjusting for baseline characteristics. Compared to men, women had higher CD4+ counts over time after initiating ART (p<0.0001).Conclusions
Our study showed that women had an overall lower mortality and higher CD4+ counts than men in response to ART treatment, which may be attributed to adherence, biological factors, social, cultural and economic reasons. Further study is needed to explore these factors that might contribute to the gender differences in mortality and immunological response to ART. 相似文献919.
Guiming Deng Ou Sheng Fangcheng Bi Chunyu Li Tongxin Dou Tao Dong Qiaosong Yang Huijun Gao Jing Liu Xiaohong Zhong Miao Peng Ganjun Yi Weidi He Chunhua Hu 《Phyton》2020,89(4):1101-1130
Banana (Musa spp.) is an ancient and popular fruit plant with highly
nutritious fruit. The pseudo-stem of banana represents on average 75% of the total
dry mass but its valorization as a nutritional and industrial by-product is limited.
Recent advances in metabolomics have paved the way to understand and evaluate
the presence of diverse sets of metabolites in different plant parts. This study
aimed at exploring the diversity of primary and secondary metabolites in the
banana pseudo-stem. Hereby, we identified and quantified 373 metabolites from
a diverse range of classes including, alkaloids, flavonoids, lipids, phenolic acids,
amino acids and its derivatives, nucleotide and its derivatives, organic acids, lignans and coumarins, tannins, and terpene using the widely-targeted metabolomics
approach. Banana pseudo-stem is enriched in metabolites for utilization in the
food industry (L-lysine and L-tryptophan, L-glutamic acid, Phenylalanine, Palmitoleic acid, α-Linolenic acid, and Lauric acid, and Adenine) and pharmaceutical
industry (Guanosine and Cimidahurinine, Bergapten, Coumarins, Procyanidin
A2, Procyanidin B1, Procyanidin B3, Procyanidin B2, and Procyanidin B4, Asiatic acid). The metabolome of banana pseudo-stem with integration across multiomics data may provide the opportunity to exploit the rich metabolome of banana
pseudo-stem for industrial and nutritional applications. 相似文献
920.