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141.
Pradeep MA Jagadeesh J De AK Kaushik JK Malakar D Kumar S Dang AK Das SK Mohanty AK 《Theriogenology》2011,75(6):1005-1015
Oviduct-specific glycoprotein (oviductin) plays an important role during fertilization and early embryonic development. The oviductin cDNA was successfully cloned and sequenced in goat, which possessed an open reading frame of 1620 nucleotides representing 539 amino acids. Predicted amino acid sequence showed very high identity with sheep (97%) followed by cow (94%), porcine (77%), hamster (69%), human (66%), rabbit (65%), mouse (64%) and baboon (62%). The bioinformatics analysis of the sequences revealed the presence of a signal sequence of 21 amino acids, one potential N-linked glycosylation site at position 402, 21 potential O-linked glycosylation sites and 36 potential phosphorylation sites. The native oviductin was purified from the oviductal tissue, which showed three distinct bands on SDS-PAGE and western blot (MW ∼60-95 kDa). The predicted molecular weight of goat oviductin was 57.5 kDa, calculated from the amino acid sequences. The observed higher molecular weight has been attributed to the presence of large number of potential O-linked glycosylation sites. The lower concentration (10 μg/mL) of oviductin increased the cleavage rate, morula and blastocyst yield significantly (P < 0.05) as compared to higher concentration (100 μg/mL). Goat oviductin retarded the activity of pronase (0.1%) on zona solubility of oocytes significantly (P < 0.01). 相似文献
142.
Human dendritic cells acquire a semimature phenotype and lymph node homing potential through interaction with CD4+CD25+ regulatory T cells 总被引:2,自引:0,他引:2
Bayry J Triebel F Kaveri SV Tough DF 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(7):4184-4193
Interactions between dendritic cells (DC) and T cells are known to involve the delivery of signals in both directions. We sought to characterize the effects on human DC of contact with different subsets of activated CD4+ T cells. The results showed that interaction with CD25(high)CD4+ regulatory T cells (Tregs) caused DC to take on very different properties than contact with naive or memory phenotype T cells. Whereas non-Tregs stimulated DC maturation, culture with Tregs produced DC with a mixed phenotype. By many criteria, Tregs inhibited DC maturation, inducing down-regulation of costimulatory molecules and T cell stimulatory activity. However, DC exposed to Tregs also showed some changes typically associated with DC maturation, namely, increased expression of CCR7 and MHC class II molecules, and gained the ability to migrate in response to the CCR7 ligand CCL19. Both soluble factors and cell-associated molecules were shown to be involved in Treg modulation of DC, with lymphocyte activation gene 3 (LAG-3) playing a predominant role in driving maturation-associated changes. The data show that Tregs induce the generation of semimature DC with the potential to migrate into lymphoid organs, suggesting a possible mechanism by which Tregs down-modulate immune responses. 相似文献
143.
Vidya SM Krishna V Manjunatha BK Mankani KL Ahmed M Singh SD 《Indian journal of experimental biology》2007,45(6):538-542
The ethanol extract of C. serratum roots and ursolic acid isolated from it were evaluated for hepatoprotective activity against carbon tetrachloride induced toxicity in male Wistar strain rats. The parameters studied were estimation of liver function serum markers such as serum total bilirubin, total protein, alanine transaminase, aspartate transaminase and alkaline phosphatase activities. The ursolic acid showed more significant hepatoprotective activity than crude extract. The histological profile of the liver tissue of the root extract and ursolic acid treated animal showed the presence of normal hepatic cords, absence of necrosis and fatty infiltration as similar to the controls. The results when compared with the standard drug silymarin, revealed that the hepatoprotective activity of the constituent ursolic acid is significant as similar to the standard drug. 相似文献
144.
Claims of intron-structure correlations have played a major role in debates surrounding split gene origins. In the formative (as opposed to disruptive or "insertional") model of split gene origins, introns represent the scars of chimaeric gene assembly. When analyzed retrospectively, formative introns should tend to fall between modular units, if such units exist, or at least to exhibit a preference for sites favorable to chimaera formation. However, there is another possible source of preferences: under a disruptive model of split gene origins, fortuitous intron-structure correlations may arise because the gain of introns is biased with respect to flanking nucleotide sequences. To investigate the extent to which a sequence-biased intron gain model may account for the present-day distribution of introns, data on over 10,000 introns in eukaryotic protein-coding genes were integrated with structural data from a set of 1,851 nonredundant protein chains. The positions of introns with respect to secondary structures, solvent accessibility, and so-called "modules" were evaluated relative to the expectations of a null model, a disruptive model based on amino acid frequencies at splice junctions, and a formative model defined relative to these. The null model can be excluded for most structural features and is highly improbable when intron sites are grouped by reading frame phase. Phase-dependent correlations with secondary structure and side-chain surface accessibility are particularly strong. However, these phase-dependent correlations are explained largely by the sequence-based disruptive model. 相似文献
145.
Electrospinning was used to prepare the nanofibrous membrane (NFM) of the composite comprising poly(vinylidene fluoride) and poly(aminophenylboronic acid) (PVdF/PAPBA-NFM). The PVdF/PAPBA-NFM displayed an excellent linear response to the detection of glucose for the concentration range of 1 to 15mM with a response time of less than 6s. Further experiments on amperometric sensing of glucose were performed in the presence of interferents such as uric acid, ascorbic acid, acetaminophen, fructose, mannose, etc. using PVdF/PAPBA-NFM. The interferents did not give significant overlapping current signal during the determination of glucose. Also, PVdF/PAPBA-NFM possesses better reproducibility toward glucose detection and storage stability. 相似文献
146.
Chetan Chandola Marco G. Casteleijn Urvashi M. Chandola Lakshmi Narayanan Gopalan Arto Urtti Muniasamy Neerathilingam 《Biochemistry and Biophysics Reports》2019
Age related macular degeneration (AMD) is a progressive, neurodegenerative disorder that leads to the severe loss of central vision in elderlies. The health of retinal pigment epithelial (RPE) cells is critical for the onset of AMD. Chronic oxidative stress along with loss of lysosomal activity is a major cause for RPE cell death during AMD. Hence, development of a molecule for targeted lysosomal delivery of therapeutic protein/drugs in RPE cells is important to prevent RPE cell death during AMD. Using human RPE cell line (ARPE-19 cells) as a study model, we confirmed that hydrogen peroxide (H2O2) induced oxidative stress results in CD44 cell surface receptor overexpression in RPE cells; hence, an important target for specific delivery to RPE cells during oxidative stress. We also demonstrate that the known nucleic acid CD44 aptamer - conjugated with a fluorescent probe (FITC) - is delivered into the lysosomes of CD44 expressing ARPE-19 cells. Hence, as a proof of concept, we demonstrate that CD44 aptamer may be used for lysosomal delivery of cargo to RPE cells under oxidative stress, similar to AMD condition. Since oxidative stress may induce wet and dry AMD, both, along with proliferative vitreoretinopathy, CD44 aptamer may be applicable as a carrier for targeted lysosomal delivery of therapeutic cargoes in ocular diseases showing oxidative stress in RPE cells. 相似文献
147.
Kais Kasem Vinod Gopalan Ali Salajegheh Cu-Tai Lu Robert A. Smith Alfred K.-Y. Lam 《Experimental cell research》2014
The aims of the present study are to investigate the clinicopathological correlations of JK-1(FAM134B) expression and its relationship to carcinogenesis in a colorectal adenoma–adenocarcinoma model. JK-1(FAM134B) protein expression was studied in a colon cancer cell line by Western blot and immunocytochemistry. JK-1(FAM134B) expression profiles at mRNA and protein levels were investigated in cancer tissues from 236 patients with colorectal adenocarcinoma and 32 patients with colorectal adenoma using real-time polymerase chain reaction and immunohistochemistry. The findings were then correlated with the clinicopathological features of these tumours. JK-1(FAM134B) protein was demonstrated in the colon cancer cells by Western blot. The protein was located in the nuclei of the tumour cells at both cellular and tissue levels. In colorectal adenocarcinomas, lower levels of JK-1(FAM134B) protein expression were associated with younger age (p=0.032), larger tumour size (p=0.004), advanced cancer stages (p=0.016) and higher rates of cancer recurrence (p=0.04). Also, lower levels of JK-1(FAM134B) mRNA expression were associated with advanced cancer stages (p=0.02) and presence of lymphovascular invasion (p=0.014). Higher JK-1(FAM134B) mRNA and protein expression levels were identified in adenomas and non-neoplastic mucosae, compared to carcinomas (p=0.005). To conclude, JK-1(FAM134B) mRNA expression and JK1 (FAM134B) protein levels varied with the different stages of progression of colorectal tumours. The expression levels of the gene were associated with clinicopathological features in patients with colorectal adenocarcinoma suggesting that JK-1(FAM134B) gene has roles in controlling some steps in the development of the invasive phenotypes from colorectal adenoma to early staged as well as advanced staged colorectal adenocarcinomas. 相似文献
148.
Victor Ujor Chidozie Victor Agu Venkat Gopalan Thaddeus Chukwuemeka Ezeji 《Applied microbiology and biotechnology》2014,98(14):6511-6521
Lignocellulose-derived microbial inhibitors such as furfural and 5-hydroxymethyl furfural adversely affect fermentation of lignocellulosic biomass hydrolysates to fuels and chemicals due to their toxicity on fermenting microbes. To harness the potential of lignocellulose as a cheap source of fermentable sugars, in situ detoxification of furfural and other lignocellulose-derived microbial inhibitors is essential. To enhance in situ detoxification and tolerance of furfural by Clostridium beijerinckii NCIMB 8052 during acetone-butanol-ethanol (ABE) fermentation, the effect of glycerol on NADH/NADPH generation and ABE production by furfural (4, 5, and 6 g/L)-challenged cultures was investigated in this study. In all instances, beneficial outcomes were observed. For example, the fermentation medium supplemented with glycerol and subjected to 5 g/L furfural elicited up to 1.8- and 3-fold increases, respectively, in NADH and NADPH levels in C. beijerinckii 8052 relative to the control culture. These critical changes are the likely underpinnings for the glycerol-mediated 2.3-fold increase in the rate of detoxification of 5 g/L furfural, substrate consumption, and ABE production compared to the unsupplemented medium. Collectively, these results demonstrate that increased intracellular NADH/NADPH in C. beijerinckii 8052 due to glycerol utilization engenders favorable effects on many aspects of cellular metabolism, including enhanced furfural reduction and increased ABE production. 相似文献
149.
Antihyperlipidemic Effect of Fisetin,a Bioflavonoid of Strawberries,Studied in Streptozotocin‐Induced Diabetic Rats
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Gopalan Sriram Prasath Sorimuthu Pillai Subramanian 《Journal of biochemical and molecular toxicology》2014,28(10):442-449
Chronic hyperglycemia in diabetes is associated with profound changes in lipid and lipoprotein metabolism, with resultant alterations in particle distribution within lipoprotein classes. In the present study, an attempt has been made to explore the antihyperlipidemic effect of fisetin in streptozotocin‐induced experimental diabetes in rats. Upon fisetin treatment to diabetic rats, the levels of blood glucose were significantly reduced with an improvement in plasma insulin. The increased levels of lipid contents in serum, hepatic, and renal tissues observed in diabetic rats were normalized upon fisetin administration. Also, the decreased levels of high‐density lipoprotein cholesterol, and increased levels of low‐density lipoprotein (LDL) and very LDL (VLDL) cholesterol in serum of diabetic rats were normalized. Oil Red O staining established a large number of intracellular lipid droplets accumulation in the diabetic rats. Fisetin treatment exacerbated the degree of lipid accumulation. The results of the present study exemplify the antihyperlipidemic property of the fisetin. 相似文献
150.