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911.
Aim
Many cancers originate and flourish in a prolonged inflammatory environment. Our aim is to understand the mechanisms of how the pathway of prostaglandin E2 (PGE2) biosynthesis and signaling can promote cancer growth in inflammatory environment at cellular and animal model levels.Main methods
In this study, a chronic inflammation pathway was mimicked with a stable cell line that over-expressed a novel human enzyme consisting of cyclooxygenase isoform-2 (COX-2) linked to microsomal (PGE2 synthase-1 (mPGES-1)) for the overproduction of pathogenic PGE2. This PGE2-producing cell line was co-cultured and co-implanted with three human cancer cell lines including prostate, lung, and colon cancers in vitro and in vivo, respectively.Key findings
Increases in cell doubling rates for the three cancer cell types in the presence of the PGE2-producing cell line were clearly observed. In addition, one of the four human PGE2 subtype receptors, EP1, was used as a model to identify PGE2-signaling involved in promoting the cancer cell growth. This finding was further proven in vivo by co-implanting the PGE2-producing cells line and the EP1-positive cancer cells into the immune deficient mice, after that, it was observed that the PGE2-producing cells promoted all three types of cancer formation in the mice.Significance
This study clearly demonstrated that the human COX-2 linked to mPGES-1 is a pathway that, when mediated by the EP, is linked to promoting cancer growth in a chronic inflammatory environment. The identified pathway could be used as a novel target for developing and advancing anti-inflammation and anti-cancer interventions. 相似文献912.
Guan TW Wu N Xia ZF Ruan JS Zhang XP Huang Y Zhang LL 《Extremophiles : life under extreme conditions》2011,15(3):373-378
A novel actinomycete strain, designated TRM 40133T, was isolated from a hypersaline habitat of Tarim basin in Xinjiang Province, north-west China. Its taxonomic status was
determined using a polyphasic approach. Phylogenetic analysis based on an almost-complete 16S rRNA gene sequence of the strain
showed that it formed a well-seperated sub-branch within the radiation of the genus Saccharopolyspora. The highest levels of 16S rRNA gene sequence similarity was found between the strain TRM 40133T and Saccharopolyspora qijiaojingensis YIM 91168T (96.5%). The chemotaxonomic characteristics of the isolate are typical for the genus Saccharopolyspora. It contained meso-DAP as the diagnostic diamino acid. Whole cell hydrolysate contained arabinose, xylose, ribose and glucose. The diagnostic
phospholipids were phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol and two unknown phospholipids. The main
menaquinone was MK-9(H6) and MK-9(H4). No mycolic acid was detected. The predominant cellular fatty acids were iso-C16:0 and anteiso-C17:0. The G+C content of the genomic DNA was 68.2 mol%. In addition, the strain TRM 40133T had a phenotypic profile that readily distinguished it from the recognized representatives of the genus Saccharopolyspora. The strain TRM 40133T therefore represents a novel species of the genus Saccharopolyspora, for which the name Saccharopolyspora lacisalsi sp. nov. is proposed. The type strain is TRM 40133T (=KCTC 19987T =CCTCC AA 2010012T). 相似文献
913.
Structural class categorizes proteins based on the amount and arrangement of the constituent secondary structures. The knowledge
of structural classes is applied in numerous important predictive tasks that address structural and functional features of
proteins. We propose novel structural class assignment methods that use one-dimensional (1D) secondary structure as the input.
The methods are designed based on a large set of low-identity sequences for which secondary structure is predicted from their
sequence (PSSAsc model) or assigned based on their tertiary structure (SSAsc). The secondary structure is encoded using a comprehensive set of features describing count, content, and size of secondary
structure segments, which are fed into a small decision tree that uses ten features to perform the assignment. The proposed
models were compared against seven secondary structure-based and ten sequence-based structural class predictors. Using the
1D secondary structure, SSAsc and PSSAsc can assign proteins to the four main structural classes, while the existing secondary structure-based assignment methods
can predict only three classes. Empirical evaluation shows that the proposed models are quite promising. Using the structure-based
assignment performed in SCOP (structural classification of proteins) as the golden standard, the accuracy of SSAsc and PSSAsc equals 76 and 75%, respectively. We show that the use of the secondary structure predicted from the sequence as an input
does not have a detrimental effect on the quality of structural class assignment when compared with using secondary structure
derived from tertiary structure. Therefore, PSSAsc can be used to perform the automated assignment of structural classes based on the sequences. 相似文献
914.
915.
916.
Kejin Liu Qinghua Liu Wei Chen Mengjun Liang Wei Luo Xianfeng Wu Yiping Ruan Jie Wang Ricong Xu Xiaojiang Zhan Jianwen Yu Jiaqing Tan Xiuqing Dong Jincai Zhang Xueqing Yu 《PloS one》2013,8(8)
Background
Periodontal disease is common among adults and is associated with an increasing risk of chronic kidney disease (CKD). We aimed to investigate the prevalence and risk factors of CKD in patients with periodontal disease in China.Methods
In the current cross-sectional study, patients with periodontal disease were included from Guangdong Provincial Stomatological Hospital between March 2011 and August 2011. CKD was defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, the presence of albuminuria, or hematuria. All patients with periodontal disease underwent a periodontal examination, including periodontal probing pocket depth, gingival recession, and clinical attachment level by Florida Probe. They completed a questionnaire and had blood and urine samples taken. The adjusted prevalence of indicators of kidney damage was calculated and risk factors associated with CKD were analyzed.Results
A total of 1392 patients with periodontal disease were invited to participate this study and 1268 completed the survey and examination. After adjusting for age and sex, the prevalence of reduced eGFR, albuminuria, and hematuria was 2.7% (95% CI 1.7–3.7), 6.7% (95% CI 5.5–8.1) and 10.9% (95% CI 9.2–12.5), respectively. The adjusted prevalence of CKD was 18.2% (95% CI 16.2–20.3). Age, male, diabetes, hypertension, history of CKD, hyperuricemia, and interleukin-6 levels (≥7.54 ng/L) were independent risk factors for reduced eGFR. Female, diabetes, hypertension, history of CKD, hyperuricemia, high level of cholesterol, and high sensitivity C-reactive protein (hsCRP) (≥1.03 mg/L) and TNF-α levels (≥1.12 ng/L) were independently associated with an increased risk of albuminuria. Female, lower education (<high school), and history of CKD were independent risk factors for hematuria.Conclusions
18.2% of Chinese patients with periodontal disease have proteinuria, hematuria, or reduced eGFR, indicating the presence of kidney damage. Whether prevention or treatment of periodontal disease can reduce the high prevalence of CKD, however, remains to be further investigated. 相似文献917.
吗啡对福尔马林引起大鼠海马内IL-2RβmRNA表达的影响 总被引:1,自引:0,他引:1
本实验采用原位杂交法观察足底注射福尔马林(For)痛敏对海马内白细胞介素2受体βmRNA(IL-2RβmRNA)生成的影响及其与吗啡、促肾上腺皮质激素(ACTH)的关系。结果表明:正常大鼠海马有IL-2RβmRNA表达,集中分布于CA1-CA4区神经元、齿状回颗粒细胞。足底注射For后6h双侧海马IL-2RβmRNA表达均增加(P〈0.05),12h达高峰,24h仍高于正常。在6h时,腹腔注射吗啡 相似文献
918.
919.
Weiwei Lu Yirui Zhang Yixian Yao Yuying Wu Han Y. H. Chen Hailin Zhang Jia Yu Caiqin Shen Qi Liu Honghua Ruan 《Phyton》2020,89(1):13-26
The priming effect (PE) induced by biochar provides a basis for
evaluating its carbon (C) sequestration potential in soils. A 60 days’ laboratory
incubation was conducted, which involved the amendment of biochar (1% of soil
mass) produced from rice straw at 300ºC (B300) and 500ºC (B500) to young (Y)
and old (O) poplar plantation soils, with the aim of studying the responses of
biochar-induced PEs to poplar plantation ages. This incubation included six
treatments: Y + CK (control), Y + B300, Y + B500, O + CK, O + B300, and O +
B500. Carbon dioxide (CO2) emissions were significantly increased (p < 0.05) in
the B300 amended soils, while it was decreased in the B500 amended soils
compared to the CK. The primed CO2 emissions were 2.35 times higher in the Y
+ B300 than the O + B300 treatments, which was measured to be 18.6 and 5.56
mg C·kg-1 with relative PEs of 12.4% and 3.35%, respectively. However, there
was little difference between the primed CO2 emissions in Y + B500 and O +
B500 treatments, which were measured to be -24.9 and -29.6 mg·C·kg-1 with
relative PEs of -16.6% and -17.8%, respectively. Dissolved organic carbon
(DOC) was significantly lower in the young poplar plantation soil than that in the
old poplar plantation soil regardless of biochar amendment throughout the
incubation, indicating greater C-limit of soil microorganisms in the young poplar
plantation soil. Using 13C isotope tracing, neither B300 nor B500 decreased
native soil-derived DOC, which indicated that the negative B500-induced PEs
were not due to a reduction in the availability of native soil-derived C. In
conclusion, the response of biochar-induced PEs to poplar plantation age
depends on biochar types while soil available C indirectly affects biocharinduced PEs. Further studies should focus on how the interactive effects between
soil C availability and microbial community impacts biochar-induced PEs. 相似文献
920.
微生物降解持久性有机污染物的研究进展与展望 总被引:1,自引:0,他引:1
持久性有机污染物(POPs)是伴随着人类工业化发展而产生的合成类污染物,具有高毒性、持久性、长迁移性和高生物富集性等特点,POPs污染物的微生物降解一直是环境科学与技术应用领域的研究热点。微生物降解技术修复POPs污染环境具有无二次污染、成本低、快速简便等优点,拥有广泛的应用前景。本文论述了各种POPs微生物分解代谢的最新研究进展,包括降解性微生物资源以及降解机制。此外,还讨论了计算生物学、合成生物学、基因组学等技术在POPs微生物降解中的潜力和应用,以期为环境中持久性有机污染物的修复提供参考。 相似文献