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131.
Jiang L  Xu J  Ni J  Gao X  Zhu Z  Dong D  Wang X  Shi C  Tao X  Dong W  Gao Y 《DNA and cell biology》2012,31(9):1480-1485
Hepatocellular carcinoma (HCC) represents the most common primary malignancy of the liver with a worldwide increasing incidence. Although the risk factors for HCC are well characterized, the molecular mechanisms responsible for malignant transformation of hepatocytes are not well understood. In this study, a case-control study including 291 HCC patients and 294 healthy controls was conducted to investigate the association between HCC susceptibility and with a 4-bp insertion/deletion polymorphism (rs66465034) in the proximal promoter of CD3G. Logistic regression analysis showed that the heterozygote and the homozygote 4-bp ins/ins confer a significantly increased risk of HCC after controlling for other covariates (adjusted odds ratio [OR]=1.51, 95% confidence interval [C.I.] 1.01-2.27, p=0.040; OR=1.71, 95% C.I. 1.07-2.89, p=0.025, respectively). Carriage of the 4-bp insertion allele was associated with a greatly increased risk of developing the disease (OR=1.30, 95% C.I. 1.02-1.64, p=0.027). Moreover, hepatitis B virus (HBV) stratification analysis showed that the differences between cases and controls were more obvious in HBV-positive than in the HBV-negative population, suggesting a possible role of this polymorphism in the immune regulation during HBV infection. Further, luciferase-based transient transfection assays revealed that rs66465034 can affect promoter activity of CD3G, indicating its possible functional significance. Our data suggested that common genetic polymorphisms in CD3G may influence HCC risk in Chinese population. Considering the relative small sample size, replication in other populations with larger sample size and further functional analysis are required for fully understanding the roles of CD3G polymorphisms in predisposition for HCC.  相似文献   
132.
Members of the papain family of cysteine proteases (cathepsins) mediate late stage processing of MHC class II-bound invariant chain (Ii), enabling dissociation of Ii, and binding of antigenic peptide to class II molecules. Recognition of cell surface class II/Ag complexes by CD4(+) T cells then leads to T cell activation. Herein, we demonstrate that a pan-active cathepsin inhibitor, SB-331750, attenuated the processing of whole cell Ii p10 to CLIP by Raji cells, and DBA/1, SJL/J, and C57BL/6 splenocytes. In Raji cells and C57BL/6 splenocytes, SB-331750 inhibited class II-associated Ii processing and reduced surface class II/CLIP expression, whereas in SB-331750-treated DBA/1 and SJL/J splenocytes, class II-associated Ii processing intermediates were undetectable. Incubation of lymph node cells/splenocytes from collagen-primed DBA/1 mice and myelin basic protein-primed SJL/J mice with Ag in the presence of SB-331750 resulted in concentration-dependent inhibition of Ag-induced proliferation. In vivo administration of SB-331750 to DBA/1, SJL/J, and C57BL/6 mice inhibited splenocyte processing of whole cell Ii p10 to CLIP. Prophylactic administration of SB-331750 to collagen-immunized/boosted DBA/1 mice delayed the onset and reduced the severity of collagen-induced arthritis (CIA), and reduced paw tissue levels of IL-1beta and TNF-alpha. Similarly, treatment of myelin basic protein-primed SJL/J lymph node cells with SB-331750 delayed the onset and reduced the severity of adoptively transferred experimental autoimmune encephalomyelitis (EAE). Therapeutic administration of SB-331750 reduced the severity of mild/moderate CIA and EAE. These results indicate that pharmacological inhibition of cathepsins attenuates CIA and EAE, potentially via inhibition of Ii processing, and subsequent Ag-induced T cell activation.  相似文献   
133.
The development of highly efficient and low‐cost electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is paramount for water splitting associated with the storage of clean and renewable energy. Here, this study reports its findings in the development of a nanostructured perovskite oxide as OER/HER bifunctional electrocatalyst for overall water splitting. Prepared by a facile electrospinning method, SrNb0.1Co0.7Fe0.2O3–δ perovskite nanorods (SNCF‐NRs) display excellent OER and HER activity and stability in an alkaline solution, benefiting from the catalytic nature of perovskites and unique structural features. More importantly, the SNCF‐NR delivers a current density of 10 mA cm?2 at a cell voltage of merely ≈1.68 V while maintaining remarkable durability when used as both anodic and cathodic catalysts in an alkaline water electrolyzer. The performance of this bifunctional perovskite material is among the best ever reported for overall water splitting, offering a cost‐effective alternative to noble metal based electrocatalysts.  相似文献   
134.
The waxy gene mutation causes waxy maize grain to have a sticky quality. China has numerous waxy maize landraces and is thought to be the place of origin of waxy maize. The most abundant waxy maize resources in China are located in the Yunnan province and its surrounding areas. We collected 57 waxy maize landraces from Yunnan province and cloned and sequenced the waxy gene from its fourth to eighth exon. Two new waxy gene mutations, named wx-Cin4 and wx-124, were identified. The wx-Cin4 mutation is a 466-bp retrotransposon inserted into exon six. The wx-124 mutation is a 116-bp miniature inverted-repeat transposable element inserted into exon seven. This is the first time a 124-type mutation has been found in a maize waxy gene. The discovery of the two specific waxy mutations from landraces collected in Yunnan province provides new evidence supporting the hypothesis that China is the origin area for waxy maize.  相似文献   
135.
136.
OBJECTIVE: We investigated the efficacy of early lung cancer screening with low-dose spiral computed tomography(LDCT) in both smokers and nonsmokers based on the current situation of community health service, with integration of superior resources of medical institutions at all levels in Shanghai. METHODS: From August 2013 to August 2014, we screened 11,332 (male 7144; female 4188) high-risk individuals in selected communities of Minhang, Shanghai City, for early diagnosis of lung cancer with LDCT combined with multidisciplinary comprehensive treatment pattern including minimally invasive surgery, exploring the medical service network covering prevention, diagnosis, treatment, rehabilitation, and follow-up. RESULTS: Screening resulted in a diagnosis of cancer in 29 participants. Of these participants, 27 had primary lung cancer, 1 had lung metastatic cancer, and 1 had breast cancer. The detection rate of primary lung cancer was 238.26 cases per 100,000 person-years among all the participants. Specifically, the incidence of primary lung cancer was 336.97 cases per 100,000 person-years among the nonsmoking participants, as compared with 159.06 cases per 100,000 person-years among the smoking participants (P = .054). Among the 27 primary lung cancers, 22 (81.48%) had stage 0 to I lung cancer. CONCLUSION: Based on community health service, screening with LDCT could improve the early diagnosis rate of lung cancer in both smokers and nonsmokers with feasibility and validity, which could be applicable in qualified eligible medical centers and communities in China. It is not reasonable to exclude nonsmokers from screening with LDCT.  相似文献   
137.
138.
The utilization of heterosis is a successful strategy in increasing yield for many crops. However, it consumes tremendous manpower to test the combining ability of the parents in fields. Here, we applied the genomic-selection (GS) strategy and developed models that significantly increase the predictability of heterosis by introducing the concept of a regional parental genetic-similarity index (PGSI) and reducing dimension in the calculation matrix in a machine-learning approach. Overall, PGSI negatively affected grain yield and several other traits but positively influenced the thousand-seed weight of the hybrids. It was found that the C subgenome of rapeseed had a greater impact on heterosis than the A subgenome. We drew maps with overviews of quantitative-trait loci that were responsible for the heterosis (h-QTLs) of various agronomic traits. Identifications and annotations of genes underlying high impacting h-QTLs were provided. Using models that we elaborated, combining abilities between an Ogu-CMS-pool member and a potential restorer can be simulated in silico, sidestepping laborious work, such as testing crosses in fields. The achievements here provide a case of heterosis prediction in polyploid genomes with relatively large genome sizes.  相似文献   
139.
LIF, a multifunctional cytokine, is frequently overexpressed in many types of solid tumors, including breast cancer, and plays an important role in promoting tumorigenesis. Currently, how LIF promotes tumorigenesis is not well-understood. Metabolic reprogramming is a hallmark of cancer cells and a key contributor to cancer progression. However, the role of LIF in cancer metabolic reprogramming is unclear. In this study, we found that LIF increases glucose uptake and drives glycolysis, contributing to breast tumorigenesis. Blocking glucose uptake largely abolishes the promoting effect of LIF on breast tumorigenesis. Mechanistically, LIF overexpression enhances glucose uptake via activating the AKT/GLUT1 axis to promote glycolysis. Blocking the AKT signaling by shRNA or its inhibitors greatly inhibits glycolysis driven by LIF and largely abolishes the promoting effect of LIF on breast tumorigenesis. These results demonstrate an important role of LIF overexpression in glucose metabolism reprogramming in breast cancers, which contributes to breast tumorigenesis. This study also reveals an important mechanism underlying metabolic reprogramming of breast cancers, and identifies LIF and its downstream signaling as potential therapeutic targets for breast cancers, especially those with LIF overexpression.Subject terms: Breast cancer, Cancer metabolism, Oncogenes  相似文献   
140.
林分空间格局研究对认识和理解森林群落结构的生态学过程具有重要作用。适宜的样地尺度不仅可以有效降低工作和时间成本,也可以提高林分属性的精确估计。同时,抽样尺度的适宜程度对科学评价林分空间结构调整也具有重要的现实意义。以关帝山庞泉沟4 hm2云杉次生林固定监测样地为研究对象,运用样地划分法和空间点格局的K2函数,评估了林分主要树种空间格局随样地面积变化的规律。结果表明:通过重要值排序,选取云杉(青杄+白杄)、华北落叶松、桦树(白桦+红桦)+其它阔叶树(花楸+辽东栎+山杨+山楂)作为主要树种(组)。随着样地尺度的减小(从4 hm2到0.25 hm2),空间分布格局主要表现为较小尺度(≤ 4 m)的聚集分布过度为随机分布与均匀分布,以及聚集和随机分布交替出现。所有树种的次级样地与参考样地的一致性指数差异显著,云杉和华北落叶松组合1 hm2样地一致性指数最高,而桦树和其它阔叶树完整1 hm2样地一致性指数最高;此外,云杉、华北落叶松和桦树0.25 hm2样地与组合1 hm2样地空间格局一致性指数组间差异显著。研究认为1 hm2样地尺度可以作为该地区云杉次生林空间分布格局的最小尺度。研究为探索云杉次生林空间格局的变化规律及样地抽样尺度的选取方面,提供了一定的理论基础和技术依据。  相似文献   
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