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961.
International Journal of Peptide Research and Therapeutics - Pidotimod has been shown to exhibit immunomodulatory activities and exert protective effects against bacterial infections. This study...  相似文献   
962.
963.
Osteoporosis is a bone disease that is caused by disorder of the skeletal microenvironment, and it characterized by a high disability rate and the occurrence of low energy fractures. Studies on osteoporosis and related treatment options have always been hot spots in the field of bone biology. In the past, the understanding of osteoporosis has been rather limited; research has only shown that osteoporosis involves the imbalance of bone resorption and bone formation, and recent studies have not provided cutting‐edge theories of the basic understanding of osteoporosis. Recent studies have shown crosstalk between bone and immune responses. RANKL, an essential factor for osteoclasts (OCs), is associated with the immune system. T helper (Th17)/regulatory T (Treg) cells are two different kinds of T cells that can self‐interact and regulate the differentiation and formation of OCs. Therefore, understanding the correlation between the skeletal and immune systems and further revealing the roles and the cooperation between RANKL and the Th17/Treg balance will help to provide new insights for the treatment of osteoporosis.  相似文献   
964.
Both the pollination control system and genetic distance are major factors in the utilization of crop heterosis. The recessive genic male sterile line (RGMS) 7-7365A (Bnms3ms3ms4ms4) has been widely applied to hybrid seed production because it can generate a completely male sterile population by crossing with the 7-7365C temporary line (Bnms3ms3rfrf). In this study, the sterile genes of 7-7365A were transferred to the new Brassica napus lines 7-749 and 7-750 with a high content of subgenomes by backcross breeding. We used the amplified fragment length polymorphism (AFLP) technique combined with bulk segregant analysis (BSA) to identify markers linked to the BnMs4 gene. Twelve AFLP markers linked to the BnMs4 gene were identified. Of them, SA06MG09 and P08MG16 were the closest makers, which were on either side of the gene at a distance of 0.9 and 0.8?cM, respectively. Twenty AFLP primer combinations were used to screen the F2, BC1F3, and BC2F4 populations from the breeding program, and the markers linked to the BnMs3 and BnMs4 genes were used to screen the BC2F4 populations. As a result, we obtained two types of improved sterile lines, 7-749A and 7-750A, and their indexes of subgenomic components (ISG) were 44.2?C49.8 and 20.2?C26.6%, respectively. The combining ability analyses of seed yield character were conducted in the crosses from the three sterile lines and ten restorers within a random block design in three environments for two successive years. The general combining ability (GCA) of the two improved sterile lines were significantly higher than the GCA of 7-7365A in every environment tested. The two improved sterile lines had stability in seed yield, and they will be used in the future for hybrid seed production.  相似文献   
965.
Alantolactone, an allergenic sesquiterpene lactone, has recently been found to have significant antitumor effects on malignant tumor cells. Here, we investigated the potential effect of alantolactone on Bcr/Abl+ imatinib-sensitive and -resistant cells. Alantolactone treatment resulted in obvious apoptosis in both imatinib-sensitive and -resistant K562 cells, as shown by the increase in Annexin V-positive cells, caspase-3 activation, poly(ADP-ribose) polymerase-1 (PARP-1) cleavage and mitochondrial membrane potential collapse. Alantolactone significantly inhibited NF-κB-dependent reporter gene activity, decreased the DNA-binding activity of NF-ОκB, and blocked TNF-α-induced IκBα phosphorylation. Of interest, the oncogenic Bcr/Abl fusion protein but not its mRNA levels were quickly reduced upon alantolactone exposure in imatinib-sensitive and -resistant K562 cells. Bcr/Abl knockdown enhanced the apoptosis driven by alantolactone. Bcr/Abl protein reduction could not be reversed by the addition of proteasome or caspase-3 inhibitors. The overexpression of p65 inhibited alantolactone-induced apoptosis, whereas p65 or Bcr/Abl silencing enhanced its apoptotic-inducing effect. Furthermore, Bcr/Abl-transfected 32D cells showed more sensitivity to alantolactone than vector-transfected control cells, and the Bcr/Abl protein was depleted, as observed in K562 cells. Finally, alantolactone-induced apoptosis was also observed in primary CD34+ CML leukemic cells. Collectively, these findings suggest that alantolactone is a promising potent agent to fight against CML cells via the inhibition of the NF-κB signaling pathway and depletion of the Bcr/Abl protein.  相似文献   
966.
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a new member of the TNF superfamily. Here, a recombinant form of the extracellular domain of the TRAIL (sTRAIL) was expressed in Escherichia coli BL21(DE3) under the control of a T7 promoter. The resulting insoluble bodies were separated from cellular debris by centrifugation and solubilized with 8 M urea. A rapid and simple on-column refolding procedure was developed. It was applied and then the refolded sTRAIL was purified by anion-exchange chromatography. The purified final product was >98% pure by SDS-PAGE stained with Coomassie brilliant blue R-250. Mass spectroscopic analysis indicated the protein to be 19.2 kDa, which equalled the theoretically expected mass. N-terminal sequencing of refolding sTRAIL showed the sequence which corresponded to the designed protein. The renatured protein displayed its immunoreactivity with the antibodies to TRAIL protein by Western blotting. The purified sTRAIL had a strong cytotoxic activity against human cervical cancer HeLa cells with ED50 about 1.5 mg/L. Circular dichroism and fluorescence spectrum analysis showed that the refolded sTRAIL had a structure similar to that of native protein with beta-sheet secondary structure. This efficient procedure of sTRAIL renaturation may be useful for the mass production of this therapeutically important protein.  相似文献   
967.
D. Huang  K. T. Chun  M. G. Goebl    P. J. Roach 《Genetics》1996,143(1):119-127
Mutations in GLC7, the gene encoding the type 1 protein phosphatase catalytic subunit, cause a variety of abberrant phenotypes in yeast, such as impaired glycogen synthesis and relief of glucose repression of the expression of some genes. Loss of function of the REG1/HEX2 gene, necessary for glucose repression of several genes, was found to suppress the glycogen-deficient phenotype of the glc7-1 allele. Deletion of REG1 in a wild-type background led to overaccumulation of glycogen as well as slow growth and an enlarged cell size. However, loss of REG1 did not suppress other phenotypes associated with GLC7 mutations, such as inability to sporulate or, in cells bearing the glc7(Y-170) allele, lack of growth at 14°. The effect of REG1 deletion on glycogen accumulation is not simply due to derepression of glucose-repressed genes, although it does require the presence of SNF1, which encodes a protein kinase essential for expression of glucose-repressed genes and for glycogen accumulation. We propose that REG1 has a role in controlling glycogen accumulation.  相似文献   
968.
Huang YW  Kuo CT  Stoner K  Huang TH  Wang LS 《FEBS letters》2011,(13):2129-2136
It is now appreciated that both genetic alteration, e.g. mutations, and aberrant epigenetic changes, e.g. DNA methylation, cause cancer. Epigenetic dysregulation is potentially reversible which makes it attractive as targets for cancer prevention. Synthetic drugs targeting enzymes, e.g. DNA methyltransferase and histone deacetylase, that regulate epigenetic patterns are active in clinical settings. In addition, dietary factors have been suggested to have potential to reverse aberrant epigenetic patterns. Uncovering the human epigenome can lead us to better understand the dynamics of DNA methylation in disease progression which can further assist in cancer prevention.  相似文献   
969.
Clonorchiasis is an important food-borne parasitic disease caused by Clonorchis sinensis infection. The evaluation of long-term cost-effectiveness of control strategies is important for disease control and prevention. The present study aimed to assess the cost-effectiveness of the three recommended strategies (i.e., WHO, Chinese and Guangdong strategies) and different combinations of commonly used measures (i.e., preventive chemotherapy, information, education, and communication (IEC) and environmental improvement) on clonorchiasis. The study area, Fusha town in Guangdong Province, was a typical high endemic area in China. The analysis was based on a multi-group transmission model of C. sinensis infection. We set the intervention duration for 10 years and post-intervention period for 50 years. The corresponding costs and DALYs were estimated. Strategies with incremental cost-effectiveness ratios (ICERs) less than 1/5 of the willingness-to-pay threshold were identified as highly cost-effective strategies. The optimal control strategy was obtained using the next best comparator method. The ICERs of Guangdong strategy were $172 (95% CI: $143-$230) US for praziquantel and $106 (95% CI: $85-$143) US for albendazole, suggesting the highest cost-effectiveness among the three recommended strategies. For praziquantel, 470 sets of control strategies were identified as highly cost-effective strategies for achieving infection control (prevalence<5%). The optimal strategy consisted of chemotherapy targeted on at-risk population, IEC and environmental improvement, with coverages all being 100%, and with the ICER of $202 (95% CI: $168-$271) US. The results for transmission control (prevalence<1%) and albendazole were obtained with the same procedures. The findings may help to develop control policies for C. sinensis infection in high endemic areas. Moreover, the method adopted is applicable for assessment of optimal strategies in other endemic areas.  相似文献   
970.
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