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71.
Transformation of maize embryogenic calli mediated by ultrasonication and regeneration of fertile transgenic plants 总被引:6,自引:0,他引:6
Zhang Hong Wang Guoying Xie Youju Dai Jingrui Xu Ning Zhao Nanming Li Taiyuan Tian Yingchuan Qiao Liya Mang Keqiang 《中国科学:生命科学英文版》1997,40(3):316-322
An insecticidal protein gene isolated fromBacillus thuringiensis was transferred into maize by using ultrasonication. The fertile transgenic plants and their progeny were obtained. The Southern
hybridization results indicated that the foreign gene had integrated into the maize genome. It has been found that the acoustic
intensity and the duration of treatment are the important parameters influencing transformation efficiency by ultrasonication.
The maximum relative transformation frequency of 34.1 % was achieved after 30 min of sonication at 0. 5 W/cm2 acoustic intensity. With appropriate parameters the ultrasonication can make a number of micropores formed on the cell surface
and minimize the treatment damage to the foreign DNA molecules, thus facilitating the DNA molecules to enter the cells.
Project supported by “863” State High Technology Development Program. 相似文献
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作者采用水媒法和溶媒法,分别将茯苓聚糖直接羧甲基化,得到了具有抗肿瘤活性的羧甲基茯苓聚糖,并对产物进行了IR、~(13)CNMR分析。 相似文献
76.
Per Stålhandske Liya Wang Sara Westberg Henrik von Euler Erika Groth Sven A. Gustafsson Staffan Eriksson Johan Lennerstrand 《Analytical biochemistry》2013,432(2):155-164
Measurement of thymidine kinase-1 (TK1) and deoxycytidine kinase (dCK) activity may be useful in cancer disease management. Therefore, a one-step homogeneous assay for real-time determination of TK1 and dCK was developed by combining enzyme complementation with fluorescent signal generation using primer extension and a quenched probe oligodeoxyribonucleotide system at 37 °C. Complementation, for producing dCTP and TTP from nucleoside substrates, was carried out by dTMP kinase and/or UMP/CMP kinase and nucleoside diphosphate kinase. dNTP was continuously incorporated into a fixed oligodeoxyribonucleotide primer, template, and probe system, and the fluorescent signal was generated by using the combined actions of primer extension and 5′ exonuclease activity of Thermophilus aquaticus (Taq) DNA polymerase for specific relief of fluorescent quenching. Fluorescence was captured at 1-min intervals using a real-time polymerase chain reaction (PCR) instrument. A horizontal threshold line, crossing all sample relative fluorescent units (RFU) values at the level of the RFU of the blank sample at the end of the assay (i.e., 90 min), was drawn, obtaining RFU measurement data in minutes for each sample. Duplex proof of principle was demonstrated by the independent determination of different amounts of dCK and TK1 in combination. R2 values of 0.90 were demonstrated with Prolifigen TK-REA U/L reference values obtained from pathological canine and human serum samples. 相似文献
77.
Richard Akuffo Michael Wilson Bismark Sarfo Naiki Attram Mba-Tihssommah Mosore Clara Yeboah Israel Cruz Jose-Antonio Ruiz-Postigo Daniel Boakye Javier Moreno Francis Anto 《PLoS neglected tropical diseases》2021,15(5)
BackgroundLeishmaniasis is a neglected tropical disease caused by parasites of the genus Leishmania and is transmitted by various species of female phlebotomine sand flies. The first report of cutaneous leishmaniasis (CL) in Ghana refer to a cluster of cases in 1999–2003 in the Ho municipality of the Volta Region. We conducted an epidemiological assessment in the Oti Region, encouraged by recent reports of potential cases of CL.Methodology/Principal findingsUsing a cross-sectional study design, the exposure to Leishmania was investigated in three communities of the Oti Region based on the leishmanin skin test (LST). LST results for 3,071 participants comprising 1091, 848, and 1132 persons from the communities of Ashiabre, Keri, and Sibi Hilltop, indicated an overall prevalence of exposure to Leishmania infection of 41.8% and individual community prevalence of 39.4%, 55.1%, and 34.2% respectively. Being male [AOR = 1.27; CI: 1.09, 1.49], and living in Keri [AOR = 1.83; CI: 1.43, 2.34] were associated with an increase in the odds of exposure to Leishmania. Being 5–10 years old [AOR = 1.48; CI: 1.06, 2.05], 11–17 years old [AOR = 2.03; CI: 1.45, 2.85], 18–40 years old [AORR = 2.83; CI: 1.81, 4.43] and 41–65 years old [AOR = 5.08; CI: 2.98, 8.68] were also significantly associated with increased odds of being exposed to Leishmania.Conclusions/SignificanceThis study demonstrated exposure to Leishmania in the study communities and also identified associated factors. Future efforts aimed at reducing exposure to Leishmania infection in the study area should take the associated factors into consideration. 相似文献
78.
Ya Su Liya Wei Hao Tan Jing Li Wenping Li Lei Fu Tongxin Wang Le Kang X. Steve Yao 《Journal of biophotonics》2020,13(2)
Noninvasive visualization of embryos at different development stages is crucial for the understanding of the basic developmental biology. It is therefore desirable to have an imaging tool capable of rapidly evaluating the effects of gene manipulation or genome editing in developing embryos for the studies of gene functions and genetic engineering. Here, we propose and demonstrate a novel use of optical coherence tomography (OCT) to noninvasively exam the embryonic development of the migratory locusts in real time with 3‐dimensional (3D) view capability. In particular, we obtain the sufficiently high spatial resolution tomographic 2D and 3D images of live locust embryos throughout their development processes. We show that not only we are able to noninvasively observe all previously known forms of blastokinesis as an embryo develops, such as anatrepsis, katatrepsis, revolution, rotation and diapauses, and determine their precise occurring time or duration, but also discover an unreported rotation form we named “twist.” In addition, with the OCT images we determined the exact occurring time of diapauses of the locusts from Tibetan plateau for the first time. Finally, we demonstrate that OCT systems can be used to rapidly capture the development defects of genetically modified embryos in which certain genes essential for embryonic development were suppressed by RNA interference. Our work shows that OCT is an enabling imaging tool with sufficient spatial resolution for the rapid evaluation of embryonic variations of small animals. 相似文献
79.
Kondratyeva Liya G. Dyachkova Marina S. Galchenko Alexey V. 《Biochemistry. Biokhimii?a》2022,87(2):150-169
Biochemistry (Moscow) - The origin of genetic code and translation system is probably the central and most difficult problem in the investigations on the origin of life and one of the most complex... 相似文献
80.
The pathogenetic mechanisms of retinoblastoma are still not yet fully elucidated, putting limits to efficacious treatment. Crocin is the main component of saffron, which exhibits significant antitumorigenic properties. The aim of this paper is to investigate the effect of crocin on retinoblastoma. The effects of crocin on the proliferation of human retinoblastoma cells were determined by the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay, cell number assay, and colony formation assay. Cell apoptosis induced by crocin was measured by flow cytometry analysis. Cleaved poly(ADP‐ribose) polymerase and cleaved caspase‐3 were tested by western blot analysis. The expression levels of MYCN were assessed by western blot and quantitative polymerase chain reaction and the stability of MYCN messenger RNA was determined by in vitro RNA degradation assays. We found that crocin significantly inhibited the cell proliferation and clonogenicity and induced cell apoptosis in Y79 and WERI‐RB‐1 cells. In addition, crocin treatment significantly reduced the expression and the stability of MYCN. Besides, overexpression of MYCN rescued the inhibitory effect of crocin in Y79 cells. Our findings suggest that crocin exhibits antitumorigenic effects in human retinoblastoma cell lines through a MYCN‐dependent manner, which may provide guidance to logical therapeutic designs in prevention and treatment of retinoblastoma. 相似文献