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971.
This study quantitatively examined myocardial changes during the hypertensive process. Four groups (n=10 for each group) of adultRattus norvegicus (Wistar strain) were studied. Animals were sacrificed at 40 and 80 days of experimentation (control and experimental groups in each age). Although animals in the experimental groups received L-NAME (50 mg/kg/day) for 40 days, one group of animals was without L-NAME for the remaining 40 days. In addition, stereology was performed to determine the volume and numerical densities of myocytes (Vv and Nv, respectively), the mean volume and the total number of myocytes (Vol and N, respectively). According to those results, the blood pressure increased following L-NAME administration and remained high even at 40 days after administering L-NAME. The cardiac weight significantly increased in L-NAME animals and also in control of older animals. Moreover, Vv and the Vol increased in older animals. Notably, inhibition of the NO synthase increased Vol while decreasing Nv and N. These indices remained unchanged even after 40 days of the L-NAME intake interruption. Nv and N also decreased in older animals. Furthermore, hypertrophy and loss of myocytes were not entirely reversible after cessation of the chronic inhibition of the NO synthase in an extended follow-up.  相似文献   
972.
973.
Journal of Applied Phycology - The global ecological awakening has made carbon–neutral production an imperative. Ignoring the call of the mermaid to protect the environment does not seem to...  相似文献   
974.
Journal of Applied Phycology - Many western countries show an increased interest in using algae in several sectors such as human food and animal feed, nutraceuticals, cosmetics and pharmaceuticals,...  相似文献   
975.
Journal of Applied Phycology - This work aimed to improve the techniques for cultivating the species Gelidium floridanum, testing different sources of calcium. Tetraspores and explants were grown...  相似文献   
976.
Introduction : Autophagy is a mechanism that is involved in the regulation of cellular life, apoptosis, and stemness while its intervening genes play important functions in various cancers including lung cancer. ATG5 is one of the key genes for the regulation of the autophagy pathway. In this study, our team has investigated the potential relationship between ATG5 gene polymorphism rs2245214 with non–small cell lung cancer (NSCLC) in a subpopulation of patients from southern Iran. In this study, 34 patients with NSCLC (20 males and 14 females [mean age: 12.86 ± 60.47 years]) and 50 healthy subjects (30 males and 20 females [mean age: 13.09 ± 56.62 years]) were studied in terms of the genotype of the ATG5 gene. We used restriction fragment length polymorphism and analyzed the results using SPSS software (v.23). The results revealed that subjects harboring the guanine/cytosine (GC) genotype of the rs2245214 ATG5 gene polymorphism had suffered less from NSCLC, whereas the prevalence of the C-allele of this polymorphism was significantly higher in patients with NSCLC ( P < 0.05). On the basis of the results of logistic regression, the presence of this C-allele may predict the risk of lung cancer ( P value = 0.011; OR, 3.52; 95% CI, 1.33-9.26). This study concludes that the C-allele of the rs2245214 ATG5 gene polymorphism is associated with increased susceptibility to NSCLC, whereas the GC genotype of this polymorphism is associated with decreased risk and might therefore have a protective role in the development of NSCLC.  相似文献   
977.
978.
Lipid rafts are specialized, cholesterol-rich membrane compartments that help to organize transmembrane signaling by restricting or promoting interactions with subsets of the cellular proteome. The hypothesis driving this study was that identifying proteins whose relative abundance in rafts is altered by the abused psychostimulant methamphetamine would contribute to fully describing the pathways involved in acute and chronic effects of the drug. Using a detergent-free method for preparing rafts from rat brain striatal membranes, we identified density gradient fractions enriched in the raft protein flotillin but deficient in calnexin and the transferrin receptor, markers of non-raft membranes. Dopamine D1- and D2-like receptor binding activity was highly enriched in the raft fractions, but pretreating rats with methamphetamine (2 mg/kg) once or repeatedly for 11 days did not alter the distribution of the receptors. LC-MS analysis of the protein composition of raft fractions from rats treated once with methamphetamine or saline identified methamphetamine-induced changes in the relative abundance of 23 raft proteins, including the monomeric GTP-binding protein Rab10, whose abundance in rafts was decreased 2.1-fold by acute methamphetamine treatment. Decreased raft localization was associated with a selective decrease in the abundance of Rab10 in a membrane fraction that includes synaptic vesicles and endosomes. Inhibiting Rab10 activity by pan-neuronal expression of a dominant-negative Rab10 mutant in Drosophila melanogaster decreased methamphetamine-induced activity and mortality and decreased caffeine-stimulated activity but not mortality, whereas inhibiting Rab10 activity selectively in cholinergic neurons had no effect. These results suggest that activation and redistribution of Rab10 is critical for some of the behavioral effects of psychostimulants.  相似文献   
979.
Diacylglycerol acyltransferase 1 (DGAT1) is a key enzyme in the triacylglyceride synthesis pathway. Bovine DGAT1 is an endoplasmic reticulum membrane-bound protein associated with the regulation of fat content in milk and meat. The aim of this study was to evaluate the interaction of DGAT1 peptides corresponding to putative substrate binding sites with different types of model membranes. Whilst these peptides are predicted to be located in an extramembranous loop of the membrane-bound protein, their hydrophobic substrates are membrane-bound molecules. In this study, peptides corresponding to the binding sites of the two substrates involved in the reaction were examined in the presence of model membranes in order to probe potential interactions between them that might influence the subsequent binding of the substrates. Whilst the conformation of one of the peptides changed upon binding several types of micelles regardless of their surface charge, suggesting binding to hydrophobic domains, the other peptide bound strongly to negatively-charged model membranes. This binding was accompanied by a change in conformation, and produced leakage of the liposome-entrapped dye calcein. The different hydrophobic and electrostatic interactions observed suggest the peptides may be involved in the interactions of the enzyme with membrane surfaces, facilitating access of the catalytic histidine to the triacylglycerol substrates.  相似文献   
980.
Reviews in Environmental Science and Bio/Technology - Halloysite nanotubes (HNTs) are of importance for the elimination of various kinds of molecules from complex matrix due to their outstanding...  相似文献   
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