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111.
pING family of conjugative plasmids from the extremely thermophilic archaeon Sulfolobus islandicus: insights into recombination and conjugation in Crenarchaeota
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Stedman KM She Q Phan H Holz I Singh H Prangishvili D Garrett R Zillig W 《Journal of bacteriology》2000,182(24):7014-7020
A novel family of conjugative plasmids from Sulfolobus comprising the active variants pING1, -4, and -6 and the functionally defective variants pING2 and -3, which require the help of an active variant for spreading, has been extensively characterized both functionally and molecularly. In view of the sparse similarity between bacterial and archaeal conjugation and the lack of a practical genetic system for Sulfolobus, we compared the functions and sequences of these variants and the previously described archaeal conjugative plasmid pNOB8 in order to identify open reading frames (ORFs) and DNA sequences that are involved in conjugative transfer and maintenance of these plasmids in Sulfolobus. The variants pING4 and -6 are reproducibly derived from pING1 in vivo by successive transpositions of an element from the Sulfolobus genome. The small defective but mobile variants pING2 and -3, which both lack a cluster of highly conserved ORFs probably involved in plasmid transfer, were shown to be formed in vivo by recombinative deletion of the larger part of the genomes of pING4 and pING6, respectively. The efficient occurrence of these recombination processes is further evidence for the striking plasticity of the Sulfolobus genome. 相似文献
112.
Eckenrode S Marron MP Nicholls R Yang MC Yang JJ Guida Fonseca LC She JX 《Human genetics》2000,106(1):14-18
Previous studies have identified a susceptibility region for insulin-dependent (type 1) diabetes mellitus on chromosome 11q13 (IDDM4). In this study, 15 polymorphic markers were analyzed for 382 affected sibpair (ASP) families with type 1 diabetes. Our analyses provided additional evidence for linkage for IDDM4 (a peak LOD score of 3.4 at D11S913). The markers with strong linkage evidence are located within an interval of approximately 6 cM between D11S4205 and GALN. We also identified polymorphisms in two candidate genes, Fas-associated death domain protein (FADD) and galanin (GALN). Analyses of the data by transmission/disequilibrium test (TDT) and extended TDT (ETDT) did not provide any evidence for association/linkage with these candidate genes. However, ETDT did reveal significant association/linkage with the marker D11S987 (P=0.0004) within the IDDM4 interval defined by ASP analyses, suggesting that IDDM4 may be in the close proximity of D11S987. 相似文献
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115.
Weili Zhou Bingtao WuQianhong She Lina ChiZhenjia Zhang 《Bioresource technology》2009,100(14):3471-3476
Investigation on a full-scale UASB treating industrial wastewater at a low organic loading rate (OLR) was conducted. Excellent treatment performance was achieved when treating the evaporator condensate of distillery wastewater at the OLR of less than 1 kg COD/m3 d. Anaerobic effluent could be discharged without further treatment, which saved energy and running cost considerably. GC–MS analysis showed that the soluble microbial products (SMPs) were decreased to a low level at the low OLR. The main SMP in the anaerobic effluent were long chain carbohydrates and esters, accounting for 55–65% of the total organic matters. Anaerobic SMP was more complex than the aerobic ones. 相似文献
116.
Qing Liu Gezhi Shen Keqin Peng Zhigang Huang Jianhua Tong Mohammed Humayun Kabir Jianhui Wang Jingzhe Zhang Genji Qin Langtao Xiao 《植物学报(英文版)》2015,57(10):819-829
Plant architecture is an important factor for crop production. Some members of microRNA156 (miR156) and their target genes SQUAMOSA Promoter‐Binding Protein‐Like (SPL) were identified to play essential roles in the establishment of plant architecture. However, the roles and regulation of miR156 is not well understood yet. Here, we identified a T‐DNA insertion mutant Osmtd1 (Oryza sativa multi‐tillering and dwarf mutant). Osmtd1 produced more tillers and displayed short stature phenotype. We determined that the dramatic morphological changes were caused by a single T‐DNA insertion in Osmtd1. Further analysis revealed that the T‐DNA insertion was located in the gene Os08g34258 encoding a putative inhibitor I family protein. Os08g34258 was knocked out and OsmiR156f was significantly upregulated in Osmtd1. Overexpression of Os08g34258 in Osmtd1 complemented the defects of the mutant architecture, while overexpression of OsmiR156f in wild‐type rice phenocopied Osmtd1. We showed that the expression of OsSPL3, OsSPL12, and OsSPL14 were significantly downregulated in Osmtd1 or OsmiR156f overexpressed lines, indicating that OsSPL3, OsSPL12, and OsSPL14 were possibly direct target genes of OsmiR156f. Our results suggested that OsmiR156f controlled plant architecture by mediating plant stature and tiller outgrowth and may be regulated by an unknown protease inhibitor I family protein. 相似文献
117.
ObjectiveTo evaluate the clinical efficacy of sorafenib as preoperative neoadjuvant therapy in patients with high risk renal cell carcinoma (RCC).ResultsAmong the 18 patients there were 13 male and 5 female, with a median age of 54.6 years. The objective response rate (ORR) of the operation on the selected patients is very high (94.4%), including 4 cases (22.2%) of partial response (PR) and 13 cases (72.2%) of stable disease (SD). After preoperative sorafenib treatment, the average tumor size of the 18 patients decreased from 7.8 cm (ranging from 3.6 to 19.2 cm) to 6.2 cm (ranging from 2.4 to 16.8 cm), and the median value of average tumor CT value decreased from 61HU to 52 HU. Among the 5 patients who had IVC tumor thrombi, the grades of tumor thrombi in 2 patients who were grade II before sorafenib treatment became grade I and grade 0 respectively, 2 patients of grade III both became grade II.ConclusionPreoperative neoadjuvant therapy with sorafenib for high risk RCC patients can significantly decrease primary tumor volume as well as tumor thrombus, which could help the nephron-sparing surgery (NSS) or radical nephrectomy to be done successfully. 相似文献
118.
Tiantian She Chuanke Zhao Junnan Feng Lixin Wang Like Qu Ke Fang Shaoqing Cai Chengchao Shou 《PloS one》2015,10(3)
Sarsaparilla, also known as Smilax Glabra Rhizome (SGR), was shown to modulate immunity, protect against liver injury, lower blood glucose and suppress cancer. However, its effects on cancer cell adhesion, migration and invasion were unclear. In the present study, we found that the supernatant of water-soluble extract from SGR (SW) could promote adhesion, inhibit migration and invasion of HepG2, MDA-MB-231 and T24 cells in vitro, as well as suppress metastasis of MDA-MB-231 cells in vivo. Results of F-actin and vinculin dual staining showed the enhanced focal adhesion in SW-treated cells. Microarray analysis indicated a repression of TGF-β1 signaling by SW treatment, which was verified by real-time RT-PCR of TGF-β1-related genes and immunoblotting of TGFBR1 protein. SW was also shown to antagonize TGF-β1-promoted cell migration. Collectively, our study revealed a new antitumor function of Sarsaparilla in counteracting invasiveness of a subset of cancer cells by inhibiting TGF-β1 signaling. 相似文献
119.
Influenza vaccines elicit antigen-specific antibodies and immune memory to protect humans from infection with drift variants. However, what supports or limits vaccine efficacy and duration is unclear. Here, we vaccinated healthy volunteers with annual vaccine formulations and investigated the dynamics of T cell, natural killer (NK) cell and antibody responses upon restimulation with heterologous or homologous influenza virus strains. Influenza vaccines induced potential memory NK cells with increased antigen-specific recall IFN-γ responses during the first 6 months. In the absence of significant changes in other NK cell markers (CD45RO, NKp44, CXCR6, CD57, NKG2C, CCR7, CD62L and CD27), influenza vaccines induced memory NK cells with the distinct feature of intracellular NKp46 expression. Indeed, surface NKp46 was internalized, and the dynamic increase in NKp46(intracellular)+CD56dim NK cells positively correlated with increased IFN-γ production to influenza virus restimulation after vaccination. In addition, anti-NKp46 antibodies blocked IFN-γ responses. These findings provide insights into a novel mechanism underlying vaccine-induced immunity and NK-related diseases, which may help to design persisting and universal vaccines in the future. 相似文献
120.
Rosemary C. She Sally Alrabaa Seung Heon Lee Meghan Norvell Andrew Wilson Cathy A. Petti 《PloS one》2015,10(3)