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991.
Yıldırım S Akar S Kuyucu M Yıldırım A Dane S Aygül R 《Cell biochemistry and function》2011,29(7):549-554
The vascular endothelial dysfunction has been implicated in the pathogenesis of migraine. Oxidized low‐density lipoprotein (ox‐LDL) may impair endothelial function. Paraoxonase‐1 (PON‐1) prevents oxidative modification of LDL cholesterol (LDL‐C). So we investigated serum PON‐1 and arylesterase (ARE) activities, PON‐1 55 L/M and 192Q/R polymorphisms and the serum lipid profile in patients with migraine. Biochemical parameters and PON‐1 polymorphism analyses were assessed in 104 patients with migraine and 86 healthy subjects. Ox‐LDL was detected by ELISA, and polymorphisms were determined using PCR–restriction fragment length polymorphism analysis. Patients with migraine had lower PON‐1 and ARE activities (p < 0·001, for both) and higher ox‐LDL and LDL‐C levels (p < 0·001, for both) and ox‐LDL: LDL‐C ratio (p < 0·005) than the controls. The genotype distribution and the allele frequencies for PON‐1 55 L/M and 192Q/R polymorphisms were not different among the study populations. The results of our current study indicate that migrainous patients have decreased serum PON‐1 and ARE activities and increased serum ox‐LDL levels, which may have a clinical importance in the treatment of migraine. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
992.
Purpose
Epidemiological data suggest that green tea (GT) consumption may protect against cardiovascular diseases (CVDs) and different types of cancer. This effect is attributed primarily to the antioxidant properties of flavanols from GT. This review provides an overview of controlled intervention studies investigating the effect of GT consumption on antioxidant effects ex vivo and in vivo.Methods
The Medline and Cochrane databases were searched independently by two investigators for controlled intervention studies (English) on GT consumption and antioxidant effects published up to June 2010. Thirty-one studies investigating antioxidant effects ex vivo [plasma antioxidant capacity (AC), DNA's resistance against oxidative induced damage) or in vivo (lipid and protein oxidation, DNA damage] met the criteria. Results were compared by considering the participants, the dose of GT, the amount of ingested flavanols, the duration of supplementation and the investigated biomarkers.Results
The comparison between the studies was difficult as relevant data, e.g., on flavanol concentration in plasma (10 of 31 studies) or on major antioxidants contributing to AC, were often missing. Lipid peroxidation and DNA damage were commonly investigated. Data on protein oxidation are scarce. An antioxidant effect of at least one parameter (increase in AC or reduction of oxidative stress marker) was observed in 15 out of 22 studies by daily consumption of GT, primarily in participants exposed to oxidative stress (smokers or mixed collectives of smokers and non-smokers and physical activity) and in 6 out of 9 studies investigating the bolus consumption of GT.Conclusion
There is limited evidence that regular consumption of GT in amounts of at least 0.6-1.5 l/day may increase AC and reduce lipid peroxidation (especially oxidation of LDL). This may contribute to the protection against CVDs and different types of cancer. Beneficial effects seem to be more likely in participants exposed to oxidative challenge. 相似文献993.
Kuipers RS Luxwolda MF Dijck-Brouwer DA Muskiet FA 《Prostaglandins, leukotrienes, and essential fatty acids》2011,85(6):369-379
Introduction
The hormonal milieus of pregnancy and lactation are driving forces of nutrient fluxes supporting infant growth and development. The decrease of insulin sensitivity with compensatory hyperinsulinemia with advancing gestation, causes adipose tissue lipolysis and hepatic de novo lipogenesis (DNL).Subjects and methods
We compared fatty acid (FA) contents and FA-indices for enzyme activities between preterm (28–36 weeks) and term (37–42) milks, and between colostrum (2–5 days), transitional (6–15) and mature (16–56) milks. We interpreted FA differences between preterm and term milks, and their changes with lactation, in terms of the well known decrease of insulin sensitivity during gestation and its subsequent postpartum restoration, respectively.Results
Compared with term colostrum, preterm colostrum contained higher indices of DNL in the breast (DNL-breast) and medium chain saturated-FA (MCSAFA), and lower DNL-liver and monounsaturated-FA (MUFA). Preterm milk also had higher docosahexaenoic acid (DHA) in colostrum and transitional milk and higher arachidonic acid (AA) in mature milk. Most preterm-term differences vanished with advancing lactation. In both preterm and term milks, DNL-breast and MCSAFA increased with advancing lactation, while DNL-liver, MUFA, long chain SAFA and AA decreased. DHA decreased in term milk. MUFA was inversely related to MCSAFA in all samples, correlated inversely with PUFA in colostrum and transitional milks, but positively in mature milk. MCSAFA correlated inversely with PUFA in mature milk.Conclusion
Higher maternal insulin sensitivity at preterm birth may be the cause of lower MUFA (a proxy for DNL-liver) and higher MCSAFA (a proxy for DNL-breast) in preterm colostrum, compared with term colostrum. Restoring insulin sensitivity after delivery may be an important driving force for milk FA-changes in early lactation. 相似文献994.
Mikio Shoji Satoshi Shibata Takayuki Sueyoshi Mariko Naito Koji Nakayama 《Microbiology and immunology》2020,64(10):643-656
Pili or fimbriae, which are filamentous structures present on the surface of bacteria, were purified from a periodontal pathogen, Porphyromonas gingivalis, in 1980s. The protein component of pili (stalk pilin), which is its major component, was named FimA; it has a molecular weight of approximately 41 kDa. Because the molecular weight of the pilin from P. gingivalis is twice that of pilins from other bacterial pili, the P. gingivalis Fim pili were suggested to be formed via a novel mechanism. In earlier studies, we reported that the FimA pilin is secreted on the cell surface as a lipoprotein precursor, and the subsequent N-terminal processing of the FimA precursor by arginine-specific proteases is necessary for Fim pili formation. The crystal structures of FimA and its related proteins were determined recently, which show that Fim pili are formed by a protease-mediated strand-exchange mechanism. The most recent study conducted by us, wherein we performed cryoelectron microscopy of the pilus structure, provided evidence in support of this mechanism. As the P. gingivalis Fim pili are formed through novel transport and assembly mechanisms, such pili are now designated as Type V pili. Surface lipoproteins, including the anchor pilin FimB of Fim pili that are present on the outer membrane, have been detected in certain Gram-negative bacteria. Here, we describe the assembly mechanisms of pili, including those of Type V and other pili, as well as the lipoprotein transport mechanisms. 相似文献
995.
Dao-Rui Yu Tao Wang Jing Huang Xing-Yue Fang Hao-Fei Fan Guo-Hui Yi Qiang Liu Yu Zhang Xiang-Zhou Zeng Qi-Bing Liu 《Journal of cellular biochemistry》2020,121(1):49-62
Acute coronary syndrome (ACS) is characterized by atherosclerotic plaque rupture with a high incidence of recurrent ischemic events. Several microRNAs are found to be aberrantly expressed in atherosclerotic plaques. This study aims to investigate the effects of microRNA-9 (miR-9) on vulnerable atherosclerotic plaque and vascular remodeling in ACS and underlying mechanisms. Microarray-based gene expression profiling was used to identify differentially expressed genes related to ACS and regulatory miRNAs. Oxidized low-density lipoprotein (lectin-like) receptor 1 (OLR1) was identified to be aberrantly activated in ACS and regulated by miR-9. OLR1 was verified as a target gene of miR-9 by bioinformatics prediction and dual luciferase reporter gene assay. The atherosclerotic models were induced in ApoE−/− mice, in which the agomir or antagomir of miR-9, or small interfering RNA (siRNA) against OLR1 were separately introduced. Serum lipid levels and expression of vascular remodeling and inflammatory response-related factors were determined, respectively. On the basis of the obtained results, in the atherosclerosis mice treated with the agomir of miR-9 and siRNA against OLR1, the p38-mitogen-activated protein kinase (p38MAPK) pathway was inhibited; levels of triglyceride, total cholesterol, low-density lipoprotein cholesterol, tumor necrosis factor-α, interleukin-6, and vascular endothelial growth factor were reduced, but the high-density lipoprotein cholesterol level was increased, along with decreased vulnerable atherosclerotic plaque area and enhanced vascular remodeling. Taken together, these findings suggested an inhibitory role miR-9 acts in the formation of vulnerable atherosclerotic plaques in ACS mice, along with a promoted vascular remodeling, via a negative feedback regulation of OLR1-mediated p38MAPK pathway. 相似文献
996.
Flávia Rodrigues De Oliveira Silva Andrea Moreira Monteiro Antônio M. Figueiredo Neto Magnus Gidlund Nilson Dias Vieira Junior Lilia Coronato Courrol 《Luminescence》2009,24(3):189-193
Low‐density lipoprotein (LDL) is known as ‘bad’ cholesterol. If too much LDL circulates in the blood it can be retained in the walls of the arteries, causing atherosclerosis. In this paper we showed an alternative method to quantify LDL using the europium tetracycline (EuTc) indicator. The optical properties of the EuTc complex were investigated in aqueous solutions containing LDL. An enhancement was observed of the europium luminescence in the solutions with LDL compared those without the lipoprotein. A method to quantify the amount of LDL in a sample, based on EuTc enhanced luminescence, is proposed. The enhancement mechanism is also discussed. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
997.
Matthew R. Richardson Xianyin Lai Joseph L. Dixon Dr. Michael Sturek Frank A. Witzmann Dr. 《Proteomics》2009,9(9):2468-2483
Although low‐density lipoprotein (LDL) plays a predominant role in atherogenesis, the low‐density lipoproteome has not been fully characterized. Moreover, alterations from a Western diet, diabetes, and physical inactivity on this proteome have yet to be determined. Accordingly, relative quantification was determined in LDL proteins from male Yucatan diabetic dyslipidemic (DD) swine in the early stages of atherosclerosis compared to healthy control (C) and non‐diabetic hyperlipidemic (H) swine. Importantly, coronary vascular dysfunction was prevented by aerobic exercise training in these animals (DDX) without altering total LDL concentration. Using 2‐DE, Western blot, label‐free quantitative MS, and selected reaction monitoring, alterations in the abundance of apolipoproteins A‐I, B, C‐III, D, E, and J and noncovalently associated proteins were determined in LDL isolated using fast protein liquid chromatography. At least 28 unique proteins, many of which were novel, were identified with high confidence. An apolipoprotein E isoform demonstrated stronger correlation to disease (percent of coronary artery segments with intimal thickening) than some traditional risk factors (total cholesterol, LDL cholesterol, and LDL/HDL cholesterol). Taken together, this work identifies new possible biomarkers, potential therapeutic targets for atherosclerosis, and generates new hypotheses regarding the role of LDL in atherogenesis. 相似文献
998.
999.
Colorectal cancer risk and dyslipidemia: A case–cohort study nested in an Italian multicentre cohort
《Cancer epidemiology》2014,38(2):144-151
BackgroundDyslipidemia is an established risk factor for many diseases, but its effect on colorectal cancer risk is less clear. We investigated the association of colorectal cancer risk with plasma triglycerides, total, HDL, and LDL cholesterol in four Italian EPIC centers.MethodsWe conducted a case–cohort study on participants recruited to four Italian EPIC centers (Turin, Varese, Naples, and Ragusa; 34,148 subjects). A random subcohort of 850 subjects was obtained and 286 colorectal cancer cases were diagnosed. Triglycerides, total and HDL cholesterol were determined in plasma samples obtained at baseline and stored at −196 °C; LDL cholesterol was calculated. Hazard ratios (HR) with 95% confidence intervals (CI), adjusted for potential confounders, were estimated by Cox regression models using the Prentice method.ResultsThe highest tertiles of total (HR 1.66, 95%CI 1.12–2.45) and LDL cholesterol (HR 1.87, 95%CI 1.27–2.76) were associated with increased colorectal cancer risk compared to lowest tertiles. Risks were greater for men than women, and for postmenopausal than premenopausal women. Highest tertiles of total and LDL cholesterol were also significantly associated with increased risks of colon cancer, distal colon cancer, and rectal cancer, but not proximal colon cancer.ConclusionsOur findings suggest that high levels of total and LDL cholesterol increase colorectal cancer risk, particularly in men and postmenopausal women. However additional studies are needed to clarify the role of plasma lipids in these cancers, particularly in view of the conflicting findings of previous studies. 相似文献
1000.