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991.
We aimed to evaluate the contribution of the G-protein β3 subunit C825T (GNB3-C825T) polymorphism to essential hypertension (EH) in Han Chinese population by performing meta-analysis. A meta-analysis was performed in 12 case-control genetic association studies including 3,020 hypertension patients and 2,790 controls from MEDLINE (PubMed) and the China National Knowledge Infrastructure platforms. The STATA 10.0 software was used in analysis. Overall, there was no significant association between the GNB3-C825T polymorphism and EH in neither additive [TT vs. CC: OR (95 % CI) = 1.11 (0.74-1.69), P = 0.61; TC vs. CC: OR (95 % CI) = 1.08 (0.89-1.31), P = 0.42], nor dominant [TT + TC vs. CC: OR (95 % CI) = 1.11 (0.86-1.42), P = 0.43] and nor recessive [TT vs. TC + CC: OR (95 % CI) = 1.04 (0.75-1.44), P = 0.81] genetic models. Although further subgroup analysis found statistically significant results [T vs. C: OR (95 % CI) = 1.50 (1.05-2.15), P = 0.03] in the southern population, but after exclusion one particular study, the significant association was disappeared. No significant result was found in the northern Han Chinese population. There was no significant association identified between GNB3-C825T polymorphism and EH in Han Chinese population. Further larger sample and well-designed studies are needed to assess the genetic association particularly in the southern Han Chinese population. 相似文献
992.
Tao Shi Kun Wang Pingfang Yang 《The Plant journal : for cell and molecular biology》2017,89(3):442-457
microRNAs (miRNAs) are important noncoding small RNAs that regulate mRNAs in eukaryotes. However, under which circumstances different miRNAs/miRNA families exhibit different evolutionary trajectories in plants remains unclear. In this study, we sequenced the small RNAs and degradome from a basal eudicot, sacred lotus (Nelumbo nucifera or lotus), to identify miRNAs and their targets. Combining with public miRNAs, we predicted 57 pre‐eudicot miRNA families from different evolutionary stages. We found that miRNA families featuring older age, higher copy and target number tend to show lower propensity for miRNA family loss (PGL) and stronger signature of purifying selection during divergence of temperate and tropical lotus. Further analyses of lotus genome revealed that there is an association between loss of miRNA families in descendent plants and in duplicated genomes. Gene dosage balance is crucial in maintaining those preferentially retained MIRNA duplicates by imposing stronger purifying selection. However, these factors and selection influencing miRNA family evolution are not applicable to the putative MIRNA‐likes. Additionally, the MIRNAs participating in lotus pollen–pistil interaction, a conserved process in angiosperms, also have a strong signature of purifying selection. Functionally, sequence divergence in MIRNAs escalates expression divergence of their target genes between temperate and tropical lotus during rhizome and leaf growth. Overall, our study unravels several important factors and selection that determine the miRNA family distribution in plants and duplicated genomes, and provides evidence for functional impact of MIRNA sequence evolution. 相似文献
993.
复合淀粉凝胶电泳同工酶分析 总被引:2,自引:0,他引:2
为了克服水解马铃薯淀粉不易获得的困难,并使“I发片淀粉凝胶电泳同工酶分析”更容易开展,普通的化学试剂马铃薯淀粉(或精制食用马铃薯淀粉)和可溶性淀粉混合物加入适当 剂被用来代替水解马铃薯淀粉制作凝胶。试验结果表明:用8 ̄10%的上述混合淀粉(5:3),添加1%的琼脂粉和2 ̄4%的蔗糖,所制成的“复合淀粉凝胶”可以很好地被切片,并成功地对许多不同类群的植物材料的PGM、PGI、MDH、AAT、SKDH 相似文献
994.
已被发现和命名的白介素有19种,其相应的受体大多也已被克隆及鉴定。白介素及其受体的结构特征决定了其信号转导和功能效应的共性和特性。许多白介素及可溶性受体在临床疾病的治疗中可能起重要作用,同时这也带动了对白介素及其受体的基因工程研究。随着基因组计划的日趋完成和一些新的分子生物学技术方法的建立,对白介素及其受体的研究在许多方面都面临着新的机遇和挑战。 相似文献
995.
Large-scale collections of Zygnemataceae in the continental United States of America were made between March and August in 1982, 1983, and 1984. Collections were made on a 31000-km transect through 35 states. Zygnemataceae were found at 318 sites was inspected. Temperature average 19°C and pH averaged 6.1 over all sites. Algal strains in collections were identified to genus, characterized for filament width, chloroplast number, and end wall type, then photographed and isolated into unialgal culture. Spirogyra was the most common genus collected(632 strains), followed in abundance by Zygnema (174 Strains) and Mougeotia (135 strains). These three genera contained 95% of the strains collected and were equally widely distributed. Strains of the three genera frequently occurred together; no genus displayed evidence of habitat specialization among the three habitat types: flowing water, permanent ponds or lakes, and temporary pools. In Spirogyra, strains with plane (flat) end walls were four times more abundant than those with replicate (interlocking) end walls. Spirogyra with plane end walls showed more variation in filament width than Zygnema, Mougeotia, or Spirogyra with replicate end walls. In Spirogyra with plane end walls, filament width was correlted with nuclear DNA content and number of strains found per collection site was twice that of other genera or Spirogyra, with replicate end walls. Spirogyra strains wider than 70 μm were more frequent on the northern part of the transect. It is proposed that polyploidy may be of widespread occurrence in Spirogyra with plane end walls and that associated morphological plasticity may account for the high apparent specied diversity and survival of the genus in a wider variety of microhabitats than occupied by other Zygnemataceae. 相似文献
996.
Cancer side population (SP) cells, which are often referred to as cancer stem cells, are thought to be responsible for lung cancer chemotherapy resistance, and currently no drug can specifically target these cells. We hypothesize low-molecular-weight heparin (LMWH) may affect the biological properties of SP cells and could be used to clinically target these cells. To test this, SP cells were isolated from cisplatin (DDP)-resistant lung adenocarcinoma A549/DDP cells by flow cytometric sorting. Compared to non-SP cells, SP cells formed increased numbers of colonies in vitro, and had a 1000-fold increase in tumorigenicity in vivo. Proliferation and apoptosis assays demonstrated LMWH had no significant effect on lung SP cell proliferation or apoptosis. However, LMWH reduced lung SP cell colony formation ability and protein expression of the multidrug transporter, ABCG2, by FACS and western blot analyses without affecting its mRNA levels by RT-PCR. Consistently, immunohistochemistry stainings of ABCG2 in LMWH-treated tumor tissues were significantly reduced compared with those in controls. Further, we found proteasomal inhibitor MG132, but not lysosomal inhibitors leupeptin and pepstatin A, could restore ABCG2 protein levels in LMWH-treated SP cells. These suggest LMWH ablates lung SP cell chemoresistance by proteasome-mediated reduction of ABCG2 protein levels without affecting its mRNA levels. We also determined LMWH combined with cisplatin could overcome cisplatin-resistance and induced lung SP cells apoptosis both in vitro and in vivo. This study provides an experimental basis for using a combination of LMWH, which targets lung SP cells, with chemotherapy to improve lung cancer survival. 相似文献
997.
Junli Hu Xiangui Lin Junhua Wang Xiangchao Cui Jue Dai Haiyan Chu Jiabao Zhang 《Applied microbiology and biotechnology》2010,88(3):781-787
The P efficiency, crop yield, and response of wheat to arbuscular mycorrhizal fungus (AMF) Glomus caledonium were tested in an experimental field with long-term (19 years) fertilizer management. The experiment included five fertilizer
treatments: organic amendment (OA), half organic amendment plus half mineral fertilizer (1/2 OM), mineral fertilizer NPK,
mineral fertilizer NK, and the control (without fertilization). AMF inoculation responsiveness (MIR) of wheat plants at acquiring
P were estimated by comparing plants grown in unsterilized soil inoculated with G. caledonium and in untreated soil containing indigenous AMF. Without AMF inoculation, higher crop yields but lower colonization rates
were observed in the NPK and two OA-inputted treatments, and NPK had significantly (P < 0.05) lower impacts on organic C and available P in soils and thereby P acquisition of wheat plants compared with OA and
1/2 OM. G. caledonium inoculation significantly (P < 0.05) increased colonization rates with the NPK and two P-deficient treatments but significantly (P < 0.05) increased vegetative biomass, crop yield, and P acquisition of wheat as well as soil alkaline phosphatase (ALP) activity,
only with the NPK treatment. This gave an MIR of ca. 45% on total P acquisition of wheat plants. There were no other remarkable
MIRs. It suggested that the MIR is determined by soil available P status, and rational combination of AMF with chemical NPK
fertilizer can compensate for organic amendments by improving P-acquisition efficiency in arable soils. 相似文献
998.
999.
Spermidine promotes nucleus pulposus autophagy as a protective mechanism against apoptosis and ameliorates disc degeneration 下载免费PDF全文
Zengming Zheng Zhou‐Guang Wang Yu Chen Jian Chen Sinan Khor Jiawei Li Zili He Qingqing Wang Hongyu Zhang Ke Xu Gong Fanghua Jian Xiao Xiangyang Wang 《Journal of cellular and molecular medicine》2018,22(6):3086-3096
Spermidine has therapeutic effects in many diseases including as heart diastolic function, myopathic defects and neurodegenerative disorders via autophagy activation. Autophagy has been found to mitigate cell apoptosis in intervertebral disc degeneration (IDD). Accordingly, we theorize that spermidine may have beneficial effects on IDD via autophagy stimulation. In this study, spermidine's effect on IDD was evaluated in tert‐butyl hydroperoxide (TBHP)‐treated nucleus pulposus cells of SD rats in vitro as well as in a puncture‐induced rat IDD model. We found that autophagy was actuated by spermidine in nucleus pulposus cells. In addition, spermidine treatment weakened the apoptotic effects of TBHP in nucleus pulposus cells. Spermidine increased the expression of anabolic proteins including Collagen‐II and aggrecan and decreased the expression of catabolic proteins including MMP13 and Adamts‐5. Additionally, autophagy blockade using 3‐MA reversed the beneficial impact of spermidine against nucleus pulposus cell apoptosis. Autophagy was thus important for spermidine's therapeutic effect on IDD. Spermidine‐treated rats had an accentuated T2‐weighted signal and a diminished histological degenerative grade than vehicle‐treated rats, showing that spermidine inhibited intervertebral disc degeneration in vivo. Thus, spermidine protects nucleus pulposus cells against apoptosis through autophagy activation and improves disc, which may be beneficial for the treatment of IDD. 相似文献
1000.
细菌样颗粒(Bacterium-like particles,BLPs)是一种新型非遗传修饰型乳酸菌表面展示技术,外源蛋白可通过锚钩蛋白锚定于经热酸处理而得的乳酸菌肽聚糖骨架表面,形成空心表面展示颗粒。因其安全性高、表面展示密度大、黏膜递送效率高,又兼有佐剂效应,BLPs广泛应用于黏膜疫苗和黏膜佐剂的开发、病毒抗原的纯化、生物催化剂的制备等领域。本文就BLPs的构建、独特优势、目前的应用及尚需解决的问题等方面进行详细综述,以期展现BLPs新型表面展示平台的广阔应用前景。 相似文献