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21.
Sense-overlapping lncRNA as a decoy of translational repressor protein for dimorphic gene expression
Christelle Alexa Garcia Perez Shungo Adachi Quang Dang Nong Nikko Adhitama Tomoaki Matsuura Toru Natsume Tadashi Wada Yasuhiko Kato Hajime Watanabe 《PLoS genetics》2021,17(7)
Long noncoding RNAs (lncRNAs) are vastly transcribed and extensively studied but lncRNAs overlapping with the sense orientation of mRNA have been poorly studied. We analyzed the lncRNA DAPALR overlapping with the 5´ UTR of the Doublesex1 (Dsx1), the male determining gene in Daphnia magna. By affinity purification, we identified an RNA binding protein, Shep as a DAPALR binding protein. Shep also binds to Dsx1 5´ UTR by recognizing the overlapping sequence and suppresses translation of the mRNA. In vitro and in vivo analyses indicated that DAPALR increased Dsx1 translation efficiency by sequestration of Shep. This regulation was impaired when the Shep binding site in DAPALR was deleted. These results suggest that Shep suppresses the unintentional translation of Dsx1 by setting a threshold; and when the sense lncRNA DAPALR is expressed, DAPALR cancels the suppression caused by Shep. This mechanism may be important to show dimorphic gene expressions such as sex determination and it may account for the binary expression in various developmental processes. 相似文献
22.
Ping Huang Yuejuan Zhang Tao Jiang Wenjiao Zeng Nong Zhang 《Molecular biology reports》2010,37(7):3097-3103
Glomerulosclerosis is considered to be the final pathway leading to the progressive loss of renal function in several kidney
diseases, transforming growth factor β1 (TGF-β1) plays a critical role in glomerulosclerosis. However, the mechanisms of TGF-β1
stimulating glomerulosclerosis remain poorly understood. Here we report that TGF-β1-induced expression of fibronectin (FN)
depends on the activity of aldose reductase (AR) in human mesangial cells (HMCs).The results show that TGF-β1 increased the
expression of FN, which attenuated by pharmacological inhibition of AR or knockdown of the enzyme by small interfering RNA
(siRNA). MAPKs (ERK, JNK and p38) signalling pathways were activated in HMCs after stimulated by TGF-β1, inhibition of AR
blunted the activation ERK, p38 and JNK signalling pathways. These changes were associated with decreased TGF-β1-induced expression
of FN. These results indicate that AR is a potent regulator of TGF-β1 induced expression of FN in human mesangial cells: it
suggests that inhibition of this enzyme may be useful to prevented extracellular matrix (ECM) deposition in glomerulosclerosis. 相似文献
23.
对太白贝母粗多糖提取工艺的研究,为太白贝母的深入综合利用提供依据。采用超声波提取太白贝母粗多糖,在单因素试验基础上,利用响应面法对提取工艺参数进行优化研究。建立料液比、时间、超声温度之间的数学模型,通过典型性分析得出最优工艺条件为:提取时间为16 min,提取温度75℃,料液比为1∶15,总糖的含量为0.461%。试验表明,响应面法对太白贝母粗多糖提取条件的优化是可行的,可用于实际预测。 相似文献
24.
Helicobacter pylori (H. pylori) infection has been associated with gastric disorders. The situation of H. pylori infection in China—where a high prevalence of H. pylori infection, a high incidence of gastric cancer, and widespread resistance to clarithromycin, metronidazole, and levofloxacin exist—is quite different from that in Western countries. In order for Chinese clinicians to better manage H. pylori infection, a Chinese Study Group on H. pylori published four consensus reports regarding the management of H. pylori infection in China between 1999 and 2012. The eradication rate with standard triple therapy was <80% in most areas of China. Bismuth is available in China, and bismuth‐containing quadruple therapy has been shown to produce a high eradication rate; thus, bismuth quadruple therapy could be recommended both as an initial and as a rescue therapy in China. There is no advantage of sequential therapy over triple therapy in Chinese patients, but the efficacy of concomitant therapy must be studied further. This review introduces the epidemiology, diagnosis, indicators, and therapies for the eradication of H. pylori in China in recent years. 相似文献
25.
Xiangqun Nong Chunqin Liu Xing Lu Qinglei Wang Guangjun Wang Zehua Zhang 《Biocontrol Science and Technology》2011,21(5):593-603
We evaluated the pathogenicity of nine isolates of entomopathogenic fungi, including six isolates of Metarhizium anisopliae, one of Beauveria bassiana, and two of Beauveria brongniartii, against eggs and various larval instars of two scarab-beetle species, Holotrichia oblita and Anomala corpulenta, under laboratory conditions. The fungal isolates differed in pathogenicity. Generally, the isolates were more pathogenic to A. corpulenta than to H. oblita. Some of the isolates prevented egg hatching and caused larval death. Isolates M2-2 and Br5-8 caused 39 and 27% egg mortality, respectively, and produced 23 and 24% viewable fungal-infection rates in H. oblita. Three isolates had no significant effect on egg hatchability. Three isolates (Br5-8, Br232818, and M200614) caused about 40% mortality in H. oblita first instars. In A. corpulenta, all isolates except M200614 caused more than 60% egg mortality, and M2-2, Br232818 and Br5-8 caused egg-infection rates greater than 50%. M2-2 caused 47% infection and 100% mortality in first-instar larvae of A. corpulenta, while Br5-8 and Br232818 yielded over 80% mortality of the larvae. The three most virulent isolates, M2-2, Br232818 and Br5-8, were selected for further bioassays against second- and third-instar larvae. In addition, seven graduated concentrations of a Br5-8 conidial suspension were assayed against H. oblita second instars. Larval mortality was positively correlated with fungal dosage, and the LC50 was 4.49×106 conidia/mL. These three virulent isolates may be used to prevent H. oblita and A. corpulenta larval infestations in field crops. 相似文献
26.
Background
Vitiligo is a chronic depigmented skin disorder with regional melanocytes depletion. The pathogenesis was not completely clarified. Recently, more and more evidence suggested that polymorphisms of some genes are associated with vitiligo risk. Here, we want to examine the association between the inducible nitric oxide synthase (iNOS) gene polymorphisms and the risk of vitiligo in Chinese populations.Methods and Principal Findings
In a hospital-based case-control study of 749 patients with vitiligo and 763 age- and sex-matched healthy controls, three polymorphisms of iNOS gene were genotyped by using the PCR-restriction fragment length polymorphism (PCR-RFLP) and mutagenically separated PCR (MS-PCR) methods, respectively. We found the iNOS-954 polymorphism was associated with a significantly higher risk of vitiligo (adjusted OR = 1.36, 95% CI = 1.02–1.81). Furthermore, this association is more pronounced in vulgaris vitiligo, active vitiligo and vitiligo without other autoimmune diseases in the stratification study. Analysis of haplotypes showed increased risk for the C -1173 C -954 CEx 16+14 (OR = 1.44, 95% CI = 1.01–1.74). In addition, the serum iNOS activity is significantly associated with iNOS-954 combined genotype (GC+CC) and is much higher in vitiligo patients than in the controls (P<0.01). Logistic regression analysis of iNOS activity showed increased risk between higher activity and iNOS-954 G→C variant genotype carriers (Ptrend<0.001).Conclusions and Significance
INOS gene polymorphisms may play an important role in the genetic susceptibility to the development of vitiligo. 相似文献27.
Zheng Guo Tianwen Zhang Xia Li Qi Wang Jianzhen Xu Hui Yu Jing Zhu Haiyun Wang Chenguang Wang Eric J Topol Qing Wang Shaoqi Rao 《BMC bioinformatics》2005,6(1):1-12
Background
Despite the continuous production of genome sequence for a number of organisms, reliable, comprehensive, and cost effective gene prediction remains problematic. This is particularly true for genomes for which there is not a large collection of known gene sequences, such as the recently published chicken genome. We used the chicken sequence to test comparative and homology-based gene-finding methods followed by experimental validation as an effective genome annotation method.Results
We performed experimental evaluation by RT-PCR of three different computational gene finders, Ensembl, SGP2 and TWINSCAN, applied to the chicken genome. A Venn diagram was computed and each component of it was evaluated. The results showed that de novo comparative methods can identify up to about 700 chicken genes with no previous evidence of expression, and can correctly extend about 40% of homology-based predictions at the 5' end.Conclusions
De novo comparative gene prediction followed by experimental verification is effective at enhancing the annotation of the newly sequenced genomes provided by standard homology-based methods. 相似文献28.
Nong C He W Fleming D Pan L Huang H 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,826(1-2):226-231
The flavonoid compound mangiferin is found in the leaves, stem bark, fruit peels and root of Mangifera indica L. and in many other herbal species with many potential pharmacological properties. We have established an analytical method of mangiferin extracted from M. indica L. bark and Mangifera persiciformis C.Y. Wu et T.L. Ming leaves utilizing CZE. An electrolytic buffer containing 0.05 M borate buffer, pH 7.4 with methanol (1:0.3, v/v) was deemed suitable for mangiferin analysis. An ideal mangiferin electropherogram with a migration time at approximately 10.50 min was obtained. Repeatability tests showed that the R.S.D.s for both intra- and inter-day migration time and peak area for all manigferin sources tested were less than 4%. The linearity range of this method was 5-1000 microg/ml. The detection limit of this method was 1.5 microg/ml. Quantitative analysis of mangiferin was also performed with this method. The accuracy of quantitation at 10, 500 and 1000 microg/ml of control mangiferin were 99.00, 99.38 and 99.14%, respectively (n=10). The repeatability of quantitation (R.S.D.) was below 3%. Our results demonstrated that CZE is a simple and reliable method in mangiferin analysis and more studies are needed to detect other mangiferin resources, such as clinical biological samples, in pharmacology and pharmacokinetic studies. 相似文献
29.
Root distribution and interactions between intercropped species 总被引:28,自引:0,他引:28
Even though ecologists and agronomists have considered the spatial root distribution of plants to be important for interspecific
interactions in natural and agricultural ecosystems, few experimental studies have quantified patterns of root distribution
dynamics and their impacts on interspecific interactions. A field experiment was conducted to investigate the relationship
between root distribution and interspecific interactions between intercropped plants. Roots were sampled twice by auger and
twice by the monolith method in wheat (Triticum aestivum L.)/maize (Zea mays L.) and faba bean (Vicia faba L.)/maize intercropping and in sole wheat, maize, and faba bean up to 100 cm depth in the soil profile. The results showed
that the roots of intercropped wheat spread under maize plants, and had much greater root length density (RLD) at all soil
depths than sole wheat. The roots of maize intercropped with wheat were limited laterally, but had a greater RLD than sole-cropped
maize. The RLD of maize intercropped with faba bean at different soil depths was influenced by intercropping to a smaller
extent compared to maize intercropped with wheat. Faba bean had a relatively shallow root distribution, and the roots of intercropped
maize spread underneath them. The results support the hypotheses that the overyielding of species showing benefit in the asymmetric
interspecific facilitation results from greater lateral deployment of roots and increased RLD, and that compatibility of the
spatial root distribution of intercropped species contributes to symmetric interspecific facilitation in the faba bean/maize
intercropping.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
30.