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101.
Homogeneous murine myeloma immunoglobulins (IgA, kappa), M 384, and M 870, bind methyl alpha-D-galactopyranoside and phosphorylcholine at different subsites. Heterologous recombinant immunoglobulins of these two immunoglobulins with M 603 (a homogeneous IgA, kappa with known phosphorylcholine specificity) also bind phosphorylcholine.  相似文献   
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103.
The present work makes an effort to assess and standardize some redox metabolic and molecular parameters for screening drought tolerant indigenous aromatic rice cultivars of West Bengal, India. PEG-induced dehydration stress during early germination caused disruption of redox-homeostasis and oxidative damage in four IARVs (Jamainadu, Tulaipanji, Sitabhog and Badshabhog) by enhancing the accumulation of pro-oxidants [assessed in terms of oxidation of 2′,7′-dichlorofluorescindiacetate (DCFDA), accumulation of \({\text{O}}_{2}^{ \cdot - }\) and H2O2 and in situ staining of reactive oxygen species (ROS) in germinating tissue], significant reduction of antioxidative defence (total antioxidant and radical scavenging capacity, total thiol content and activities of antioxidative defence enzymes) and aggravating protein oxidation and lipid peroxidation (assessed in terms of free carbonyl content and accumulation of thiobarbituric acid reactive substances). When compared between the indigenous aromatic rice cultivars, a clear trend in differential redox regulatory properties in which ROS-antioxidant interaction acts at metabolic interface for redox homeostasis was observed in the order Badshabhog > Tulaipanji > Sitabhog > Jamainadu. Moreover, when the efficacy of ascorbate–glutathione cycle for scavenging H2O2 generated during dehydration stress was assessed and compared between the landraces exposed to PEG-induced dehydration stress in germinating tissue, it also exhibited almost the same trend with the landrace Tulaipanji and Badsabhog exhibiting maximum and Jamainadu the minimum efficiencies of the redox cycle. The indigenous aromatic rice cultivars Tulaipanji and Badsabhog resist dehydration stress better than the other two landraces due to its early preparedness to combat oxidative stress by up-regulating expression of genes of some enzymes of ascorbate–glutathione cycle along with some other antioxidative enzymes. A model of redox homeostasis in which ROS-antioxidant (ascorbate–glutathione system) acts at metabolic interface for up-regulation of antioxidative gene expression necessary for differential drought stress tolerance among the indigenous aromatic rice varieties is suggested.  相似文献   
104.
The work focuses towards interaction of harmaline, with nucleic acids of different motifs by multispectroscopic and calorimetric techniques. Findings of this study suggest that binding constant varied in the order single‐stranded (ss) poly(A) > double‐stranded calf thymus (CT) DNA > double‐stranded poly(G)·poly(C) > clover leaf tRNAPhe. Prominent structural changes of ss poly(A), CT DNA, and poly(G)· poly(C) with concomitant induction of optical activity in the bound achiral alkaloid molecule was observed, while with tRNAPhe, very weak induced circular dichroism perturbation was seen. The interaction was predominantly exothermic, enthalpy driven, and entropy favored with CT DNA and poly(G)·poly(C), while it was entropy driven with poly(A) and tRNAPhe. Intercalated state of harmaline inside poly(A), CT DNA, and poly(G)·poly(C) was shown by viscometry, ferrocyanide quenching, and molecular docking. All these findings unequivocally pointed out preference of harmaline towards ss poly(A) inducing self‐structure formation. Furthermore, harmaline administration caused a significant decrease in proliferation of HeLa and HepG2 cells with GI50 of 28μM and 11.2μM, respectively. Nucleic acid fragmentation, cellular ultramorphological changes, decreased mitochondrial membrane potential, upregulation of p53 and caspase 3, generation of reactive oxygen species, and a significant increase in the G2/M population made HepG2 more prone to apoptosis than are HeLa cells.  相似文献   
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Genetic characterization of Barilius barna, an economically important freshwater fish in the Indian scenario, is unexplored in the sub-Himalayan Dooars region of West Bengal, India. This study is the first attempt to characterize the genetic architecture of Barilius barna from the Teesta river of this region. We have studied loci polymorphism, genetic diversity, Shannon’s information index and the measure of evenness in the two populations of this river through ten RAPD and seven ISSR primer-based PCR amplifications. The result showed 89.52 and 82.21% polymorphisms in RAPD and ISSR amplification respectively. The Nei’s genetic diversity and Shannon’s information index varied from 0.172 ± 0.189SD to 0.293 ± 0.164SD and 0.265 ± 0.268SD to 0.445 ± 0.220SD respectively, which indicated low level of genetic variation. AMOVA revealed significant level of variance within the population and gene flow between the populations. Low levels of genetic variation and moderate to high levels of genetic relatedness were found in the studied populations. Expectedly, the populations were genetically not very distant from each other, as evident from the Nei’s unbiased measure of genetic distance and identity. As the species is commercially important and the region is located in the sub-Himalayan region, the management and proper rehabilitation of this ichthyofauna in the wild is urgently required. Our results may serve as a guideline for adopting such management decisions.  相似文献   
107.
Tendinopathy, an important sports injury afflicting athletes and general public, is associated with huge economic losses. The currently used diagnostic tests are subjective, show moderate sensitivity and specificity; while treatment failures persist despite advances in therapy. This highlights the need for tendinopathy diagnostic and treatment monitoring tools. This study investigates tendon injury, natural healing and effect of treatment using ATR‐FTIR complemented with histopathology. Control (C), injured (I) and treated (T) rat tendons were extracted 3, 7, 14 and 28 days post‐injury/treatment, representing phases of healing; and subjected to hematoxylin & eosin staining as well as spectroscopy. While C showed no change, I‐ and T‐related histological changes could be clearly observed in stained sections. ATR‐FTIR spectra highlighted the biochemical changes within groups. Multivariate analysis could classify C, I and T with 75%; different days between groups with 84%; and different days within group with 65% efficiency. Results suggest that such analysis can not only identify C, I or T but also different phases of healing. Difference between I and T at different time points also suggest change in rate of healing. Further studies may help develop this technique for clinical diagnosis and treatment monitoring in future.   相似文献   
108.
Membrane lipid peroxidation, activity of free radical scavangers and ethylene evolution of Amaranthus lividus seedlings were used to determine the lead and cadmium (1, 10, 100 and 1000 μM) induced phytotoxicity. Malondialdehyde (MDA) accumulation and higher lipoxygenase activity (LOX) was found in the 7-d-old treated seedlings. The activities of free radical scavangers like peroxidase, catalase and superoxide dismutase declined considerably with the concomitant rise in hydrogen peroxide level. Heavy metal treatment also caused decline in ethylene evolution in germinating seedlings. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
109.
Cyclic nucleotide phosphodiesterase 11A (PDE11A) is the newest member in the PDE family. Although the tissue distribution of PDE11A mRNA has been shown, its protein expression pattern has not been well studied. The goal of this report is to investigate the distribution of PDE11A proteins in a wide range of normal and malignant human tissues. We utilized a polyclonal antibody that recognized all four PDE11A isoforms. Its specificity was demonstrated by Western blot analysis on a recombinant human PDE11A protein and native PDE11A proteins in various human tissues. Immunohistochemistry showed that PDE11A is widely expressed. Various degrees of immunoreactivity were observed in the epithelial cells, endothelial cells, and smooth muscle cells of all tissues examined. The highest expression was in the epithelial, endothelial, and smooth muscle cells of the prostate, Leydig, and spermatogenic cells of the testis, the tubule epithelial cells in the kidney, the epithelial and endothelial cells in the adrenal, the epithelial cells and macrophages in the colon, and the epidermis in the skin. Furthermore, PDE11A expression was also detected in several human carcinomas. Our results suggest that PDE11A might be involved in multiple physiological processes in various organs via its ability to modulate intracellular cAMP and cGMP levels.  相似文献   
110.
Induction and complementation of lysine auxotrophs in Saccharomyces   总被引:1,自引:0,他引:1  
Four chemical agents, EMS EMS: Ethyl methanesulfonate; MNNG: N-methyl-N\t'-nitro-N\t'-nitrosoguanidine; NA: Nitrous acid; ICR-170: 2-methoxy-6-chloro-9-[3-(ethyl-2-chloroethyl) aminopropylamino] acridine 2 HCl; UV: Ultra violet radiation. , MNNG, NA, ICR-170, as well as UV were used to induce mutations in the wild-type haploid strain X2180-1B (α) of Saccharomyces. A total of 2053 (EMS, 427; MNNG, 444; NA, 469; ICR-170, 456; UV, 257) lysine-requiring mutant clones were isolated from many independent treatments and by nystatin enrichment technique. Mutants were classified into various functional groups on the basis of complementation analysis with 14 tester strains (lys 1 to lys 15 except lys 3). Of the clones analyzed, the number of isolates unable to complement with a given tester strain ranged from 2 for lys 5 to 918 for lys 4. Three of the mutually complementing lysine loci (lys 1, lys 2, and lys 4) accounted together for over 85% of the mutant clones whereas lys 6, lys 7, lys 8, and lys 14 had less than 10 noncomplementing isolates each. Mutants for lys 4 were most frequent with all of the mutagens tested except with NA in which case the mutants for lys 2 were most frequent. A total of 56 isolates failed to complement with lys 10, lys 11, and lys 12. Similarly, 47 isolates failed to complement with lys 9 and lys 13 simultaneously. Only 44 isolates complemented with all of the tester strains used.  相似文献   
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