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161.
The analytical scale of most mass‐spectrometry‐based targeted proteomics assays is usually limited by assay performance and instrument utilization. A recently introduced method, called triggered by offset, multiplexed, accurate mass, high resolution, and absolute quantitation (TOMAHAQ), combines both peptide and sample multiplexing to simultaneously improve analytical scale and quantitative performance. In the present work, critical technical requirements and data analysis considerations for successful implementation of the TOMAHAQ technique based on the study of a total of 185 target peptides across over 200 clinical plasma samples are discussed. Importantly, it is observed that significant interference originate from the TMTzero reporter ion used for the synthetic trigger peptides. This interference is not expected because only TMT10plex reporter ions from the target peptides should be observed under typical TOMAHAQ conditions. In order to unlock the great promise of the technique for high throughput quantification, here a post‐acquisition data correction strategy to deconvolute the reporter ion superposition and recover reliable data is proposed.  相似文献   
162.
QTL pyramiding for producing nutritious and safe rice grains   总被引:1,自引:0,他引:1  
正Breeding of rice varieties that are enriched with essential micronutrients and simultaneously have reduced levels of toxic elements in grains is largely unexplored in rice breeding practice. In this issue of JIPB, Liu et al.(2020)developed two rice lines with a low level of cadmium and simultaneously high levels of zinc or selenium accumulation in the grains, thus providing elite genetic materials for breeding rice varieties that are important for addressing mineral malnutrition and ensuring food safety.m entary  相似文献   
163.
Rice is a major source of cadmium(Cd) intake for Asian people. Indica rice usually accumulates more Cd in shoots and grains than Japonica rice. However, underlying genetic bases for differential Cd accumulation between Indica and Japonica rice are still unknown. In this study, we cloned a quantitative trait locus(QTL) grain Cd concentration on chromosome 7(GCC7) responsible for differential grain Cd accumulation between two rice varieties by performing QTL analysis and map-based cloning. We found that the two GCC7 alleles, GCC7~(PA64s) and GCC7~(93-11), had different promoter activity of OsHMA3,leading to different OsHMA3 expression and different shoot and grain Cd concentrations. By analyzing the distribution of different haplotypes of GCC7 among diverse rice accessions, we discovered that the high and low Cd accumulation alleles, namely GCC7~(93-11) and GCC7~(PA64s), were preferentially distributed in Indica and Japonica rice,respectively. We further showed that the GCC7~(PA64s)allele can be used to replace the GCC7~(93-11) allele in the super cultivar 93-11 to reduce grain Cd concentration without adverse effect on agronomic traits. Our results thus reveal that the QTL GCC7 with sequence variation in the OsHMA3 promoter is an important determinant controlling differential grain Cd accumulation between Indica and Japonica rice.  相似文献   
164.
野生田头菇菌株的驯化及其子实体营养成分分析   总被引:1,自引:0,他引:1  
采自湖南洞庭湖大通湖区芦苇湿地的野生菌株,经鉴定为田头菇Agrocybe praecox。通过驯化实现人工栽培,栽培原料以芦苇屑为主,使用液体菌种和覆土栽培方式,初潮菇平均生物转化率为45.6%。营养成分分析表明:以芦苇屑为栽培培养基,子实体中矿物元素含量分别为K(2 190mg/kg)、Fe(16.2mg/kg)、Mg(59.7mg/kg)、Ca(33.4mg/kg),必需氨基酸含量占比高达44.85%,谷氨酸、蛋氨酸、天冬氨酸含量高,是一种高蛋白、低脂肪、高钾低钠的食用菌。  相似文献   
165.
Flowering time and plant height are key agronomic traits that directly affect soybean (Glycine max) yield. APETALA1 (AP1) functions as a class A gene in the ABCE model for floral organ development, helping to specify carpel, stamen, petal, and sepal identities. There are four AP1 homologs in soybean, all of which are mainly expressed in the shoot apex. Here, we used clustered regularly interspaced short palindromic repeats (CRISPR) – CRISPR‐associated protein 9 technology to generate a homozygous quadruple mutant, gmap1, with loss‐of‐function mutations in all four GmAP1 genes. Under short‐day (SD) conditions, the gmap1 quadruple mutant exhibited delayed flowering, changes in flower morphology, and increased node number and internode length, resulting in plants that were taller than the wild type. Conversely, overexpression of GmAP1a resulted in early flowering and reduced plant height compared to the wild type under SD conditions. The gmap1 mutant and the overexpression lines also exhibited altered expression of several genes related to flowering and gibberellic acid metabolism, thereby providing insight into the role of GmAP1 in the regulatory networks controlling flowering time and plant height in soybean. Increased node number is the trait with the most promise for enhancing soybean pod number and grain yield. Therefore, the mutant alleles of the four AP1 homologs described here will be invaluable for molecular breeding of improved soybean yield.  相似文献   
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167.
Bone loss (osteopenia) is a common complication in human solid tumour. In addition, after surgical treatment of gynaecological tumour, osteoporosis often occurs due to the withdrawal of oestrogen. The major characteristic of osteoporosis is the low bone mass with micro-architectural deteriorated bone tissue. And the main cause is the overactivation of osteoclastogenesis, which is one of the most important therapeutic targets. Inflammation could induce the interaction of RANKL/RANK, which is the promoter of osteoclastogenesis. Triptolide is derived from the traditional Chinese herb lei gong teng, presented multiple biological effects, including anti-cancer, anti-inflammation and immunosuppression. We hypothesized that triptolide could inhibits osteoclastogenesis by suppressing inflammation activation. In this study, we confirmed that triptolide could suppress RANKL-induced osteoclastogenesis in bone marrow mononuclear cells (BMMCs) and RAW264.7 cells and inhibited the osteoclast bone resorption functions. PI3K-AKT-NFATc1 pathway is one of the most important downstream pathways of RANKL-induced osteogenesis. The experiments in vitro indicated that triptolide suppresses the activation of PI3K-AKT-NFATc1 pathway and the target point located at the upstream of AKT because both NFATc1 overexpression and AKT phosphorylation could ameliorate the triptolide suppression effects. The expression of MDM2 was elevated, which demonstrated the MDM-p53-induced cell death might contribute to the osteoclastogenesis suppression. Ovariectomy-induced bone loss and inflammation activation were also found to be ameliorated in the experiments in vivo. In summary, the new effect of anti-cancer drug triptolide was demonstrated to be anti-osteoclastogenesis, and we demonstrated triptolide might be a promising therapy for bone loss caused by tumour.  相似文献   
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