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41.
Qing-Lai Dang Jacob Marfo Fengguo Du Rongzhou Man Sahari Inoue 《Journal of Plant Ecology》2021,14(2):291
北方针叶树CO2 的刺激和响应机制随光强而变化
黑云杉(Picea mariana [Mill.] B.S.P.)和白云杉(Picea glauca [Moench] Voss.)是同属物种,两者都是适度耐阴,并且在北美北方针叶林中广泛分布。为了了解光照对CO2 浓度升高的生理生态反应的影响,在三种光照条件下(温室中光照设置为100%、50%和30%)将一年生的两种幼苗暴露在360和720 µmol mol–1 浓度的CO2环境中,测定了其中后期叶面气体交换量。研究结果表明,CO2的浓度升高提高了净光合速率 (Pn)和光合水分利用效率,但降低了气孔导度和蒸腾作用。CO2对光合作用的刺激在50%光照下最大, 在100%光照下最小。光合作用、最大羧化速率(Vcmax)和光饱和电子传递速率(Jmax)均随光照强度的 降低而降低。升高的CO2在所有光照处理中显著降低了Vcmax,在生长季节中期,两种云杉的Vcmax均显著 降低,但在生长季节后期,当光照达到30%时,这一影响变得不明显,而且黑云杉的响应大于白云杉。CO2 浓度升高也降低了白云杉的Jmax,但在生长季后期30%光照时,这种影响变得不显著。但CO2 浓度升高对 黑云杉的影响随时间而变化。在所有光照处理中,CO2 浓度升高降低了黑云杉生长中期的Jmax,且在生长后 期30%光照时影响不显著,但在100%和50%光照时,Jmax升高。这些研究结果表明,两个树种植物都受益于CO2 浓度的升高,但它们的响应机制随着光照的增加而变化:即在100%和50%光照下,它们的响应主要是生理上的,而在30%光照下,它们的响应主要是形态上的。 相似文献
42.
Hui Ming Qianfeng Wang Yuwen Zhang Luzhang Ji Lu Cheng Xiangru Huo Zixiang Yan Zhexiao Liu Yongjun Dang Bo Wen 《蛋白质与细胞》2021,12(4):297-304
Dear Editor,
In the nucleus of higher eukaryotes, chromatin occupies only a small proportion of the nuclear space, while many proteins and RNAs segregate into membrane-less nuclear bodies (NBs).These NBs follow a stochastic or ordered assembly model and constantly exchange components with the surrounding nucleoplasm (Jain et al., 2016).Typical NBs include nucleoli, nuclear speckles, paraspeckles, PML bodies, Cajal bodies, polycomb bodies and Sam68 bodies,which play critical roles in various biological processes such as ribosome assembly, RNA processing, and protein modification.The dysfunction of nuclear bodies may cause diseases, such as cancer (Li et al., 2019). 相似文献
43.
Kelly Finke Michael Kourakos Gabriela Brown Huyen Trang Dang Shi Jie Samuel Tan Yuval B. Simons Shweta Ramdas Alejandro A. Schffer Rachel L. Kember Maja Buan Sara Mathieson 《PLoS computational biology》2021,17(2)
In this work we develop a novel algorithm for reconstructing the genomes of ancestral individuals, given genotype or sequence data from contemporary individuals and an extended pedigree of family relationships. A pedigree with complete genomes for every individual enables the study of allele frequency dynamics and haplotype diversity across generations, including deviations from neutrality such as transmission distortion. When studying heritable diseases, ancestral haplotypes can be used to augment genome-wide association studies and track disease inheritance patterns. The building blocks of our reconstruction algorithm are segments of Identity-By-Descent (IBD) shared between two or more genotyped individuals. The method alternates between identifying a source for each IBD segment and assembling IBD segments placed within each ancestral individual. Unlike previous approaches, our method is able to accommodate complex pedigree structures with hundreds of individuals genotyped at millions of SNPs.We apply our method to an Old Order Amish pedigree from Lancaster, Pennsylvania, whose founders came to North America from Europe during the early 18th century. The pedigree includes 1338 individuals from the past 12 generations, 394 with genotype data. The motivation for reconstruction is to understand the genetic basis of diseases segregating in the family through tracking haplotype transmission over time. Using our algorithm thread, we are able to reconstruct an average of 224 ancestral individuals per chromosome. For these ancestral individuals, on average we reconstruct 79% of their haplotypes. We also identify a region on chromosome 16 that is difficult to reconstruct—we find that this region harbors a short Amish-specific copy number variation and the gene HYDIN. thread was developed for endogamous populations, but can be applied to any extensive pedigree with the recent generations genotyped. We anticipate that this type of practical ancestral reconstruction will become more common and necessary to understand rare and complex heritable diseases in extended families. 相似文献
44.
Imbs A. B. Ermolenko E. V. Grigorchuk V. P. Dang L. T. P. 《Russian Journal of Marine Biology》2021,47(4):312-317
Russian Journal of Marine Biology - To assess the biodiversity of symbiotic dinoflagellates (SD) in hydrocorals, we compared the molecular species compositions of four SD lipid classes such as... 相似文献
45.
Gang Chen Dongxia Feng Li Zhang Baoqi Dang Huixiang Liu Zhong Wang 《Cell biochemistry and biophysics》2013,66(3):671-680
This study aimed to investigate the expression of the Nemo-like kinase (NLK) in the brain after experimental subarachnoid hemorrhage (SAH) in rats. A total of 90 rats were randomly divided into six groups: control group, day 1, day 3, day 5, day 7, and day 14. Day 1, day 3, day 5, day 7, and day 14 groups were all SAH groups in which the rats were killed on days 1, 3, 5, 7, and 14, respectively. In SAH groups, autologous arterial blood was injected into cisterna magna once on day 0. Cross-sectional area of basilar artery was measured by H&E staining. Immunostaining and immunoblotting experiments were performed to detect the expression of NLK protein. Real-time polymerase chain reaction was used to analyze the presence and quantity of NLK mRNA. The level of oxidative stress in the artery was also measured. The basilar arteries exhibited vasospasm after SAH and became the most severe on day 3. The expressions of NLK protein and mRNA were decreased remarkably in SAH groups compared with the control group. The down-regulated expression of NLK was detected after SAH and the low ebb was on day 3, which was oppositely the peak time of oxidative stress. The expression of NLK was present mainly in the neurons in the brain and smooth muscle cells in the basilar artery. NLK is decreasingly expressed in an opposite time-course to the development of cerebral vasospasm (CVS) and SAH-induced brain injury in this rat experimental model of SAH and these findings might have important implications during the administration of specific NLK agonist to prevent or reduce CVS or neuronal apoptosis caused by SAH. 相似文献
46.
Mei Zeng Baofeng Chen Yufeng Qing Wenguang Xie Wantai Dang Mingcai Zhao 《Nucleosides, nucleotides & nucleic acids》2013,32(7):455-465
Glut9 is highly expressed in the human kidney proximal convoluted tubular and plays a crucial role in the regulation of plasma urate levels. The gene effects were stronger among women. Our results show that 17-β-estradiol (E2) through ER (estrogen receptor) β downregulates Glut9 protein expression on human renal tubular epithelial cell line (HK2). Intriguingly, E2 does not affect the expression of Glut9 mRNA. ERβ is linked to PTEN, the PTEN gene negatively regulates the PI3K/AKT pathway, and the PI3K/AKT pathway inhibition may lead to autophagy. Further study indicates that ERβ may affect the expression of Glut9 though autophagy. 相似文献
47.
Zhigang Chen Xin He Wenjie Xia Qi Huang Zhigang Zhang Jun Ye Chao Ni Pin Wu Dang Wu Jinghong Xu Fuming Qiu Jian Huang 《PloS one》2013,8(12)
Background
The prognostic value of HIFs in colorectal cancer was evaluated in a large number of studies, but the conclusions were inconclusive. Meanwhile, clinicopathologic differences of HIF-1α and HIF-2α were rarely compared in recent studies.Methodology
Identical search strategies were used to search relevant literatures in the PubMed and Web of Science databases. The prognostic significances and clinicopathological differences of HIFs in CRC were analyzed.Principal Findings
A total of 23studies comprising 2984 CRC patients met the inclusion criteria. The results indicated that overexpressed HIFs were significantly associated with increase of mortality risk, including overall survival (OS) (HR 2.06 95%CI 1.55–2.74) and disease free survival (HR 2.84, 95%CI 1.87–4.31). Subgroup analysis revealed that both overexpressed HIF-1α and HIF-2α had correlations with worse prognosis. The pooled HRs were 2.01 (95% CI: 1.55–2.6) and 2.07(95% CI: 1.01–4.26). Further subgroup analysis on HIF-1α was performed by study location, number of patients, quality score and cut-off value. The results showed that HIF-1α overexpression was significantly associated with poor OS, particularly in Asian countries (HR 2.3, 95% CI: 1.74–3.01), while not in European or other countries. In addition, overexpression of HIF-1α was closely related with these clinicopathological features, including Dukes'' stages (OR 0.39, 95% CI: 0.17–0.89), UICC stages (OR 0.42 95% CI: 0.3–0.59), depth of invasion (OR 0.71, 95% CI: 0.51–0.99), lymphnode status (OR 0.49, 95% CI: 0.32–0.73) and metastasis (OR 0.29, 95% CI: 0.11–0.81). While overexpression of HIF-2α was only associated with grade of differentiation (OR 0.48, 95% CI: 0.29–0.81).Conclusions
This study showed that both HIF-1α and HIF-2α overexpression were associated with an unfavorable prognosis. HIF-1α overexpression seemed to be associated with worse prognosis in Asian countries. Additionally, HIF-1α and HIF-2α indicated distinct clinicopathologic features. 相似文献48.
49.
hOGG1 Ser326Cys Polymorphism and Risk of Hepatocellular Carcinoma among East Asians: A Meta-Analysis
Wenjun Wang Shuangsuo Dang Yaping Li Mingzhu Sun Xiaoli Jia Rui Wang Jingkun Liu 《PloS one》2013,8(4)
Background
The hOGG1 gene encodes a DNA glycosylase enzyme responsible for DNA repair. The Ser326Cys polymorphism in this gene may influence its repair ability and thus plays a role in carcinogenesis. Several case-control studies have been conducted on this polymorphism and its relationship with the risk of hepatocellular carcinoma (HCC) among East Asians. However, their results are inconsistent.Methods
We performed a meta-analysis of published case-control studies assessing the association of the hOGG1 Ser326Cys polymorphism with HCC risk among East Asians. PubMed, EMBASE, SCI, BIOSIS, CNKI and WanFang databases were searched. A random-effect model was used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs). Analyses were conducted for additive, dominant and recessive genetic models.Results
Eight studies were identified involving 2369 cases and 2442 controls assessing the association of the hOGG1 Ser326Cys polymorphism with HCC risk among East Asians. Applying a dominant genetic model, only in the Chinese population, the Cys allele was significantly associated with increased risk of HCC (OR 1.56, 95% CI 1.12–2.17). However, two studies influenced this finding according to sensitivity analysis. Furthermore, considerable heterogeneity and bias existed among Chinese studies.Conclusion
There is limited evidence to support that the hOGG1 Ser326Cys polymorphism is associated with HCC risk among East Asians. Well-designed and large-sized studies are required to determine this relationship. 相似文献50.
Kenneth K. Poon Bich N. Dang Jessica A. Davila Christine Hartman Thomas P. Giordano 《PloS one》2013,8(3)