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941.
本文对绿色草莓(Fragaria viridis Duch.)及其自交后代5个株系的生物学特性进行了观察,其生物学特性与母本均存在一定程度差异,在观察的67个性状中,我们获得了可溶性固形物等42个差异明显的性状。利用SPSS软件对其中15个差异明显性状进行主成分分析和变异系数分析,结果表明植株高度、植株冠径、小花梗长、小花梗粗、叶柄粗、花序梗粗及花粉生活力是区分绿色草莓及其自交后代株系的重要指标。5个自交一代株系自交坐果率差异明显,其中株系Ls-S1-4属于自交不亲和最强的株系。本研究为绿色草莓自交亲和/不亲和系的创建奠定基础。 相似文献
942.
Apoptosis-inducing factor (AIF) plays a crucial role in caspase-independent programmed cell death by triggering chromatin condensation and DNA fragmentation. Therefore, it might be involved in cell homeostasis and tumor development. In this study, we report significant AIF downregulation in the majority of renal cell carcinomas (RCC). In a group of RCC specimens, 84% (43 out of 51) had AIF downregulation by immunohistochemistry stain. Additional 10 kidney tumors, including an oxyphilic adenoma, also had significant AIF downregulation by Northern blot analysis. The mechanisms of the AIF downregulation included both AIF deletion and its promoter methylation. Forced expression of AIF in RCC cell lines induced massive apoptosis. Further analysis revealed that AIF interacted with STK3, a known regulator of apoptosis, and enhanced its phosphorylation at Thr180. These results suggest that AIF downregulation is a common event in kidney tumor development. AIF loss may lead to decreased STK3 activity, defective apoptosis and malignant transformation. 相似文献
943.
Ning Wang Hongyu Zhang Bing-Qiang Zhang Wei Liu Zhonglin Zhang Min Qiao Hongmei Zhang Fang Deng Ningning Wu Xian Chen Sheng Wen Junhui Zhang Zhan Liao Qian Zhang Zhengjian Yan Liangjun Yin Jixing Ye Youlin Deng Hue H. Luu Rex C. Haydon Houjie Liang Tong-Chuan He 《PloS one》2014,9(4)
Three-dimensional organoids have been recently established from various tissue-specific progenitors (such as intestinal stem cells), induced pluripotent stem cells, or embryonic stem cells. These cultured self-sustaining stem cell–based organoids may become valuable systems to study the roles of tissue-specific stem cells in tissue genesis and disease development. It is thus conceivable that effective genetic manipulations in such organoids may allow us to reconstruct disease processes and/or develop novel therapeutics. Recombinant adenoviruses are one of the most commonly used viral vectors for in vitro and in vivo gene deliveries. In this study, we investigate if adenoviruses can be used to effectively deliver transgenes into the cultured “mini-gut” organoids derived from intestinal stem cells. Using adenoviral vectors that express fluorescent proteins, we demonstrate that adenoviruses can effectively deliver transgenes into the cultured 3-D “mini-gut” organoids. The transgene expression can last at least 10 days in the cultured organoids. As a proof-of-principle experiment, we demonstrate that adenovirus-mediated noggin expression effectively support the survival and self-renewal of mini-gut organoids, while adenovirus-mediated expression of BMP4 inhibits the self-sustainability and proliferation of the organoids. Thus, our results strongly suggest that adenovirus vectors can be explored as effective gene delivery vehicles to introduce genetic manipulations in 3-D organoids. 相似文献
944.
The interaction between the two perpendicular Fabry–Perot-like resonances of the antenna–dielectric–slit structure and their influences on the transmission enhancement are investigated with a finite-difference time-domain method. The transmission enhancement is found with the antenna width corresponding to a Fabry–Perot-like resonance condition in the antenna–dielectric–slit structure; otherwise, there is no such an enhancement even when the slit is positioned under the magnetic field maximum. On the other hand, the resonance characteristics of the vertical slit can also modify the field distribution in the horizontal cavity by changing the phase difference at the two antenna ends. It is shown that the enhanced transmission can be realized in a wide range of incident wavelengths from the visible to near-infrared regime for different slit geometries. The physical mechanism of extraordinary optical transmission is discussed with a theoretical dispersion relationship of surface plasmon polaritons based on a metal–insulator–metal cavity model. 相似文献
945.
Hui-Chen Wu Qiao Wang Hwai-I Yang Wei-Yann Tsai Chien-Jen Chen Regina M Santella 《Epigenetics》2013,8(9):962-969
We previously reported that global DNA hypomethylation, measured as Sat2 methylation in white blood cells (WBC), and aflatoxin B1 (AFB1) exposure were associated with increased hepatocellular carcinoma risk. In this study, we assessed the association between AFB1 exposure and global DNA methylation. We measured LINE-1 and Sat2 methylation in WBC DNA samples from 1140 cancer free participants of the Cancer Screening Program (CSP) cohort. Blood and urine samples were used to determine the level of AFB1-albumin (AFB1-Alb) adducts and urinary AFB1 metabolites. In continuous models, we found reverse associations of urinary AFB1 with LINE-1 and Sat2 methylation. The odds ratio (OR) per 1 unit decrease were 1.12 (95%CI = 1.03–1.22) for LINE-1 and 1.48 (95%CI = 1.10–2.00) for Sat2 methylation. When compared with subjects in the highest quartile of LINE-1, we found that individuals in the 2nd and 3rd quartiles were less likely to have detectable AFB1-Alb adducts, with ORs (95%CI) of 0.61 (0.40–0.93), 0.61 (0.40-.94), and 1.09 (0.69–1.72), respectively. The OR for detectable AFB1-Alb was 1.81 (95%CI = 1.15–2.85) for subjects in the lowest quartile of Sat2 methylation. The OR for detection of urinary AFB1 for those with LINE-1 methylation in the lowest quartile compared with those in the highest quartile was 1.87 (95%CI = 1.15–3.04). The corresponding OR was 1.75 (95%CI = 1.08–2.82) for subjects in the lowest quartile of Sat2 methylation. The association between AFB1 exposure and global DNA methylation may have implications for the epigenetic effect of AFB1 on hepatocellular carcinoma development and also suggests that changes in DNA methylation may represent an epigenetic biomarker of dietary AFB1 exposure. 相似文献
946.
Wen-Ting Chu Ji-Long Zhang Qing-Chuan Zheng Lin Chen Yun-Jian Wu Qiao Xue Hong-Xing Zhang 《Journal of molecular modeling》2013,19(3):1301-1309
The odorant binding protein of Culex quinquefasciatus (CquiOBP1), expressed on the insect antenna, is crucial for the investigation of trapping baited with oviposition semi-chemicals and controlling mosquito populations. The acidic titratable residues pKa prediction and the ligand binding poses investigation in two systems (pH 7 and pH 5) are studied by constant pH molecular dynamics (CpHMD) and molecular docking methods. Research results reveal that the change of the protonation states would disrupt some important H-bonds, such as Asp 66-Asp 70, Glu 105-Asn 102, etc. The cleavage of these H-bonds leads to the movement of the relative position of hydrophobic tunnel, N- and C- termini loops and pH-sensing triad (His23-Tyr54-Val125) in acid solution. Ligand MOP has lower affinity and shows different binding poses to protein CquiOBP1 at pH 5. This ligand may be released from another tunnel between helices α3 and α4 in acidic environment. However, it would bind to the protein with high affinity in neutral environment. This work could provide more penetrating understanding of the pH-induced ligand-releasing mechanism. 相似文献
947.
Chandini M. Thirukkumaran Zhong Qiao Shi Joanne Luider Karen Kopciuk He Gao Nizar Bahlis Paola Neri Mark Pho Doug Stewart Adnan Mansoor Don G. Morris 《Autophagy》2013,9(3):413-415
Multiple myeloma (MM) is a clonal plasma cell malignancy that accounts for 10–15% of newly diagnosed hematological cancers. Although significant advances have been made in the treatment of MM the disease still remains incurable. The oncolytic potential of reovirus has previously been demonstrated by others and us and is currently in phase III clinical trials for solid tumors. In addition a phase I clinical trial has recently been initiated for MM. Despite the clinical activity, the mechanism(s) of cell death caused by reovirus in MM is yet not well elucidated. A comprehensive understanding of reovirus-mediated histology-specific cell death mechanisms is imperative if this therapeutic is to become a standard of care for patients. Previously we have shown that reovirus-mediated cell death of breast and prostate cancer is orchestrated via apoptosis. The present study demonstrates for the first time that in addition to inducing apoptosis reovirus also upregulates autophagy during oncolysis of MM. 相似文献
948.
Lumicella rotundata
gen.
et
sp. n. is described based on specimens from Fujian Province, China. Habitus photos and illustrations of male genitalia of this new species are provided. Differences between the new genus and closely related genera are discussed. 相似文献
949.
To investigate insecticide resistance and dynamic changes of carboxylesterase polymorphism in mosquitoes with time in the Culex pipiens complex (Diptera: Culicidae), nine field mosquito populations were collected in China. The resistance levels of fourth-instar larvae to organophosphate (dichlorvos, parathion, and chlorpyrifos), carbamate (fenobucarb and propoxur), and pyrethroid (permethrin, deltamethrin and tetramethrin) insecticides were determined by bioassay. Larvae had more resistance to organophosphate insecticides than to carbamate insecticides. A low but significant resistance was observed for carbamate insecticides. The resistance to pyrethroid insecticides varied from sensitive to high. Starch gel electrophoresis revealed the presence of the overproduced esterases B1, A2B2, A8B8, A9B9, B10 and A11B11. The frequency of each overproduced esterases varied depending on its regional localities. Compared with published surveys, the C. pipiens complex, which exhibited a high polymorphism of applied esterase alleles in China, showed dynamic evolution over time under local specific insecticide selection. The results are discussed in the context of recent alterations to insecticide campaigns, and in the evolution of resistance genes in Chinese C. pipiens populations. 相似文献
950.
Guirong Qiao Haiying Li Mingying Liu Jing Jiang Yafang Yin Ling Zhang Renying Zhuo 《In vitro cellular & developmental biology. Plant》2013,49(4):375-382
Bamboo varieties are very difficult to improve by traditional breeding methods. Here, we established an efficient plant-regeneration system for Dendrocalamus latiflorus (tropical giant bamboo) by anther culture. Culture conditions, especially the plant growth regulators required for callus induction and shoot differentiation, were optimized by orthogonal design. M8 medium supplemented with 5.37 μΜ α-naphthaleneacetic acid (NAA), 1.33 μM?N 6 -benzyladenine (BA), 110.17 μM phenylacetic acid (PAA), and a pretreatment time of 3 d produced the highest rate (5.08?±?0.61%) of callus induction. The maximum shoot differentiation rate reached 28.3?±?4.29% in M8 medium supplemented with 2.32 μM kinetin (KT), 8.89 μM BA, 1.08 μM NAA, and 110.17 μM PAA. The results of the ploidy level test showed that most of the regenerated plants were dodecaploid (96/100), a few were hexaploid (3/100), and one was triploid (1/100). The average chlorophyll content of dodecaploid lines was significantly higher than that of hexaploid lines. The present study provides an innovative method for bamboo ploidy breeding and a useful method for genetic improvement. 相似文献