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351.
Heltianu C Robciuc A Botez G Musina C Stancu C Sima AV Simionescu M 《Cell biochemistry and biophysics》2011,61(1):209-216
Lysosomal acid lipase (LAL), the only lysosomal enzyme involved in the hydrolysis of LDL-cholesteryl esters, is a key regulator
of cellular cholesterol and fatty acid homeostasis and its deficiency contributes to the pathophysiology of various diseases.
In this study, we questioned whether oxidized or glycated LDL, a common occurrence in atherosclerosis and diabetes, affect
the activity and expression of LAL in vascular endothelial cells (EC) and smooth muscle cells (SMC). LAL activity and expression
were assayed in cultured human EC and SMC exposed to oxidized LDL (oxLDL), (±)9-hydroxyoctadecadienoic acid-cholesteryl ester
(HODE), glycated LDL (gLDL), or native LDL (nLDL) as control, in the presence or absence of LXR or PPAR-gamma agonists. We
found that LAL activity and expression were significantly down regulated by oxLDL and HODE in EC, and by gLDL in SMC. The
LXR agonist T0901317 reversed the decreased LAL expression in modified LDL- or HODE-exposed EC (P < 0.001) and in gLDL-exposed SMC, whereas PPAR-gamma agonist rosiglitazone induced a low effect only in EC. In conclusion,
modified LDL down regulates LAL expression in human EC and SMC by a process involving the LXR signaling pathway. This is the
first demonstration that modified LDL modulate LAL expression, in a cell specific manner. 相似文献
352.
Oancea S Wagner A Cîrstea E Sima M 《Roumanian archives of microbiology and immunology》2011,70(4):174-177
Celiac disease (CD) is a chronic intestinal disorder of public health concern caused by gluten ingestion in sensitive individuals. Gluten is a protein found not only in gluten-containing food but also as normal component of drugs and dietary supplements. Detection of gluten in dietary supplements is a very important task required for establishing their gluten status, which is highly important for the safety of products consumed by CD and gluten-sensitive patients. In this paper, we investigated the presence of gluten in twenty one common dietary supplements from the national market using the immunochromatographic assay. This visual assay proved to be an efficient rapid tool for gluten screening as an alternative to the ELISA techniques. The results have shown the presence of gluten in 23.8% of the investigated samples (vitamins, minerals, plant extracts, probiotics supplements, lactoferrin, propolis supplements). The results provide information which may contribute to the completion of the existing lists of gluten-free pharmaceuticals. It is known that for CD patients obtaining accurate information about the gluten content of a particular item is a difficult and time-consuming process. 相似文献
353.
Multi objective land allocation (MOLA) for zoning Ghamishloo Wildlife Sanctuary in Iran 总被引:2,自引:0,他引:2
Shila Hajehforooshnia Alireza Soffianian A. Salman Mahiny Sima Fakheran 《Journal for Nature Conservation》2011,19(4):254-262
Protected area zoning is an approach towards decreasing conflict between the possible uses of land and providing an opportunity for policy making. GIS data processing and spatial analysis along with decision analysis techniques, were used in this study to define zones for Ghamishloo Wildlife Sanctuary according to I.U.C.N. category IV in Isfahan Province of Iran. We used multi-criteria evaluation and multi-objective land allocation for zoning the sanctuary, which covers an area of about 866 km2. First, we prepared a land use map of the area using classification of the IRS 6 (AWiFS) data of May 2005. For zoning this region, nine major criteria including wildlife habitat, vegetation cover, soil, distance to historical places, water resources, road, scenic beauties in the landscape, and also to residential areas, and to the core zone were considered. We used the analytical hierarchy process to derive weights of the criteria and then applied a weighted linear combination technique to combine the factors. The degree of suitability was defined by applying Fuzzy membership function. The wildlife sanctuary was divided into four zones including conservation, recreation, rehabilitation, and cultural zones, consisting of 69%, 21%, 9.5% and 0.5% of the area, respectively. Finally, multi-objective land allocation (MOLA) function was used for allocation of the sanctuary's land area to the zones which produced reasonable results. 相似文献
354.
Javad Alizadeh Aleksandra Glogowska James Thliveris Forouh Kalantari Shahla Shojaei Sabine Hombach-Klonisch Thomas Klonisch Saeid Ghavami 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2018,1865(5):749-768
Lung cancer is considered one of the most frequent causes of cancer-related death worldwide and Non-Small Cell Lung Cancer (NSCLC) accounts for 80% of all lung cancer cases. Autophagy is a cellular process responsible for the recycling of damaged organelles and protein aggregates. Transforming growth factor beta-1 (TGFβ1) is involved in Epithelial to Mesenchymal Transition (EMT) and autophagy induction in different cancer models and plays an important role in the pathogenesis of NSCLC. It is not clear how autophagy can regulate EMT in NSCLC cells. In the present study, we have investigated the regulatory role of autophagy in EMT induction in NSCLC and show that TGFβ1 can simultaneously induce both autophagy and EMT in the NSCL lines A549 and H1975. Upon chemical inhibition of autophagy using Bafilomycin-A1, the expression of the mesenchymal marker vimentin and N-cadherin was reduced. Immunoblotting and immunocytochemistry (ICC) showed that the mesenchymal marker vimentin was significantly downregulated upon TGFβ1 treatment in ATG7 knockdown cells when compared to corresponding cells treated with scramble shRNA (negative control), while E-cadherin was unchanged. Furthermore, autophagy inhibition (Bafilomycin A1 and ATG7 knockdown) decreased two important mesenchymal functions, migration and contraction, of NSCLC cells upon TGFβ1 treatment. This study identified a crucial role of autophagy as a potential positive regulator of TGFβ1-induced EMT in NSCLC cells and identifies inhibitors of autophagy as promising new drugs in antagonizing the role of EMT inducers, like TGFβ1, in the clinical progression of NSCLC. 相似文献
355.
Interleukin 12: a potential link between nerve cells and the immune response in inflammatory disorders. 总被引:4,自引:0,他引:4 下载免费PDF全文
356.
Mostafa Paridar Abbas Khosravi Mohammad-Ali Jalali-Far Sima Zolfaghari Omid Kiani Ghaleh Sardi Mehdi Sajadi 《生物学前沿》2018,13(3):226-234
Background
The determination of the role of mobile sites, as compared with fixed sites, in providing safe blood supply will help with the planning of future programs.Materials and Methods
This retrospective study was carried out at the Khuzestan Blood Transfusion Organization from 2007 to 2012. Samples of the blood collected at mobile sites and fixed sites were compared. Comparisons took into consideration noticeable trends as well as the prevalence of major TTIs including HIV, HBV and HCV.Results
The total number of blood donations from 2007 to 2012 was 621117 out of which 89590 (14.43%) were collected from mobile sites. The overall blood donation index was estimated at 23.8 per 1000 population. The prevalence of HIV, HBV and HCV in mobile site donations was 5.31, 320.34 and 117.4, and in fixed sites was 5.31, 214.72 and 104.83 per 100000 donations respectively. HBV prevalence in mobile sites was significantly higher than in fixed sites (p = 0.014).Conclusion
The blood donation index in Khuzestan province is much better when compared with areas of similar socioeconomic status as well as neighboring countries. The allotment of blood units collected by mobile teams is lower than that of national reports. In addition, the prevalence of TTIs in mobile site blood donations was higher than at fixed sites.357.
Mohammad R. Khoshfetrat Fatemeh Mohammadi Sima Mortazavi Arash Rashidi Tirang Neyestani Naser Kalantari Ahmad Esmaillzadeh 《Biological trace element research》2013,153(1-3):171-177
There is no study that assessed the effect of co-supplementation of iron and vitamin C on biomarkers of oxidative stress in non-anemic iron-deficient females. We investigated the effects of iron vs. iron?+?vitamin C co-supplementation on biomarkers of oxidative stress in iron-deficient girls. In a double-blind randomized controlled clinical trial, performed among 60 non-anemic iron-deficient girls, participants were randomly assigned to receive either 50 mg/day elemental iron supplements or 50 mg/day elemental iron?+?500 mg/day ascorbic acid for 12 weeks. Fasting blood samples were taken at baseline, weeks 6 and 12 for assessment of biomarkers of oxidative stress. Compared with the baseline levels, both iron and iron?+?vitamin C supplementation resulted in a significant reduction in serum malondialdehyde (MDA) levels (P time?<?0.001) and remarkable elevation in serum total antioxidant capacity (TAC; P time?<?0.001) and vitamin C levels (P time?=?0.001); however, comparing the two groups we failed to find an additional effect of iron?+?vitamin C supplementation to that of iron alone on serum TAC and MDA levels (P group was not statistically significant). Iron?+?vitamin C supplementation influenced serum vitamin C levels much more than that by iron alone (P group?<?0.01). We also found a significant interaction term between time and group about serum vitamin C levels while this interaction was not significant about serum TAC and MDA levels. In conclusion, we found that iron supplementation with/without vitamin C improve biomarkers of oxidative stress among non-anemic iron-deficient females and may strengthen the antioxidant defense system by decreasing reactive oxygen species. Co-supplementation of iron?+?vitamin C has no further effect on oxidative stress compared with iron alone. 相似文献
358.
Sima Beigoli Atena Sharifi Rad Azam Askari Reza Assaran Darban 《Journal of biomolecular structure & dynamics》2019,37(9):2265-2282
The present study was designed to investigate the influence of two indispensable and two dispensable amino acids, including methionine, histidine, cysteine and proline, on the binding interaction between human serum albumin (HSA) and an antibiotic agent lomefloxacin (LMF). The fluorescence quenching experiments showed that the intrinsic emission of HSA was considerably quenched following binding to LMF in all the systems. Furthermore, in all the interactions the maximum wavelength of HSA was slightly decreased. The spectral changes observed in the binding systems we e all attributed to the alteration of the micro-environment around the tryptophan and tyrosine residues of HSA. The Kb values o HSA-LMF complex in the absence and presence of histidine, methionine, cysteine and proline have been obtained 6.02 × 105, 4.83 × 105, 5.05 × 105, 4.94 × 105 and 6.20 × 105 M?1 respectively. The various kind of Kb values showed the different interaction behavior between HSA and LMF in the absence and presence of amino acids mentioned. The data gathered by isothermal titration calorimetry (ITC) studies revealed that although all the binding interactions were exothermic, the amount of the heat exchanged during the HSA-LMF interaction increased in the presence of the amino acids especially cysteine. In the present study, the binding kinetics and affinity of LMF to HSA in the absence and presence of the amino acids were studies using stopped-flow circular dichroism and ITC techniques respectively. The results of these two techniques revealed that the bindig affinity and binding rate of the LMF-HSA interaction decreased in the presence of histidine, methionine and cysteine. In the presence of proline, the binding process of LMF-HSA was sped up and the affinity of LMF to HSA slightly increased. All the experimental results were then supported by the data collected from molecular modeling studies using density functional theory.
Communicated by Ramaswamy H. Sarma 相似文献
359.
Ting Wang Yang Liu Li Sima Liang Shi Zhaoming Wang Chunhui Ni Zhengdong Zhang Meilin Wang 《PloS one》2012,7(11)
Background
The -93G>A (rs1800734) polymorphism located in the promoter of mismatch repair gene, MLH1, has been identified as a low-penetrance variant for cancer risk. Many published studies have evaluated the association between the MLH1 -93G>A polymorphism and colorectal cancer (CRC) risk. However, the results remain conflicting rather than conclusive.Objective
The aim of this study was to assess the association between the MLH1 -93G>A polymorphism and the risk of CRC.Methods
To derive a more precise estimation of the association, a meta-analysis of six studies (17,791 cases and 13,782 controls) was performed. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the strength of the association. Four of these published studies were performed on subjects of known microsatellite instability (MSI) status. An additional analysis including 742 cases and 10,895 controls was used to assess the association between the MLH1 -93G>A polymorphism and the risk of MSI-CRC.Results
The overall results indicated that the variant genotypes were associated with a significantly increased risk of CRC (AG versus GG: OR = 1.06, 95% CI = 1.01–1.11; AA/AG versus GG: OR = 1.06, 95% CI = 1.01–1.11). This increased risk was also found during stratified analysis of MSI status (AA versus GG: OR = 2.52, 95% CI = 1.94–3.28; AG versus GG: OR = 1.29, 95% CI = 1.10–1.52; AA/AG versus GG: OR = 1.45, 95% CI = 1.24–1.68; AA versus AG/GG: OR = 2.29, 95% CI = 1.78–2.96). Egger’s test did not show any evidence of publication bias.Conclusion
Our results suggest that the MLH1 -93G>A polymorphism may contribute to individual susceptibility to CRC and act as a risk factor for MSI-CRC. 相似文献360.
Transmission of Escherichia coli O157:H7 from Contaminated Manure and Irrigation Water to Lettuce Plant Tissue and Its Subsequent Internalization 总被引:7,自引:0,他引:7 下载免费PDF全文
The transmission of Escherichia coli O157:H7 from manure-contaminated soil and irrigation water to lettuce plants was demonstrated using laser scanning confocal microscopy, epifluorescence microscopy, and recovery of viable cells from the inner tissues of plants. E. coli O157:H7 migrated to internal locations in plant tissue and was thus protected from the action of sanitizing agents by virtue of its inaccessibility. Experiments demonstrate that E. coli O157:H7 can enter the lettuce plant through the root system and migrate throughout the edible portion of the plant. 相似文献