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971.
MITOPLD is a member of the phospholipase D superfamily proteins conserved among diverse species. Zucchini (Zuc), the Drosophila homolog of MITOPLD, has been implicated in primary biogenesis of Piwi-interacting RNAs (piRNAs). By contrast, MITOPLD has been shown to hydrolyze cardiolipin in the outer membrane of mitochondria to generate phosphatidic acid, which is a signaling molecule. To assess whether the mammalian MITOPLD is involved in piRNA biogenesis, we generated Mitopld mutant mice. The mice display meiotic arrest during spermatogenesis, demethylation and derepression of retrotransposons, and defects in primary piRNA biogenesis. Furthermore, in mutant germ cells, mitochondria and the components of the nuage, a perinuclear structure involved in piRNA biogenesis/function, are mislocalized to regions around the centrosome, suggesting that MITOPLD may be involved in microtubule-dependent localization of mitochondria and these proteins. Our results indicate a conserved role for MITOPLD/Zuc in the piRNA pathway and link mitochondrial membrane metabolism/signaling to small RNA biogenesis.  相似文献   
972.
BACKGROUND/AIM: The cardiovascular effects of postmenopausal hormone replacement are controversially discussed. We investigated the effects of 12 months of treatment with conjugated equine estrogen and medroxyprogesterone acetate on lipoprotein(a) [Lp(a)] and other lipoproteins in Japanese postmenopausal women (PMW) with and without dyslipidemia. METHODS: Forty-three normolipidemic and 17 dyslipidemic PMW [total cholesterol (TC) >/=220 mg/dl or triglyceride (TG) >/=150 mg/dl] received conjugated equine estrogen (0.625 mg) plus medroxyprogesterone acetate (2.5 mg) daily for 12 months, and the results were compared with those of 26 normolipidemic and 14 dyslipidemic subjects declining this treatment as controls. The fasting serum levels of Lp(a), TC, TG, high-density lipoprotein cholesterol, low- density lipoprotein cholesterol, apolipoprotein (Apo) AI, Apo AII, Apo B, Apo CII, and Apo E were measured in each subject at baseline and 12 months after this treatment initiation. RESULTS: The treatment decreased Lp(a) similarly in normolipidemic and dyslipidemic PMW and decreased TC, low-density lipoprotein cholesterol, Apo CII, and Apo E and increased high-density lipoprotein cholesterol, Apo AI, and Apo AII in both groups. The therapy also significantly increased TG in normolipidemic but not dyslipidemic subjects. In controls, the levels of Lp(a) and other lipoproteins were unaltered. CONCLUSIONS: In PMW with or without dyslipidemia, improvement in Lp(a) and other lipoproteins may represent cardiovascular benefits of hormone replacement therapy. However, an elevation of the TG levels seen with the therapy warrants caution, especially in PMW without dyslipidemia.  相似文献   
973.
Genomic DNA encoding the Pleurotus ostreatus LccK laccase was fused with the Coprinopsis cinerea β-tubulin promoter and terminator, and introduced into a C. cinerea strain. Linkage analysis, native PAGE separations, substrate specificity investigations and expression profiling indicated that C. cinerea transformants secrete P. ostreatus LccK, suggesting that the introns of the lccK gene are correctly spliced and the signal peptide for secretion is functional in C. cinerea. Transformants constitutively expressing laccase may be useful for the degradation of aromatic compounds.  相似文献   
974.
A new type of planar chiral (Rp)‐ and (Sp)‐4,7,12,15‐tetrasubstituted [2.2]paracyclophanes was prepared from racemic 4,7,12,15‐tetrabromo[2.2]paracyclophane as the starting substrate. Regioselective lithiation and transformations afforded racemic bis‐(para)‐pseudo‐meta‐type [2.2]paracyclophane (4,15‐dibromo‐7,12‐dihydroxy[2.2]paracyclophane). Its optical resolution was performed by the diastereomer method using a chiral camphanoyl group as the chiral auxiliary. The diastereoisomers were readily isolated by simple silica gel column chromatography, and the successive hydrolysis afforded (Rp)‐ and (Sp)‐bis‐(para)‐pseudo‐meta‐type [2.2]paracyclophanes ((Rp)‐ and (Sp)‐4,15‐dibromo‐7,12‐dihydroxy[2.2]paracyclophanes). They can be used as pseudo‐meta‐substituted chiral building blocks.  相似文献   
975.
The effect of protein depletion on the metabolism of body collagen and muscle protein has been investigated in young male rats fed with a protein-free diet for 14 and 28 days.

During the protein depletion, the protein content of the liver, intestine and skin decreased significantly, but the decrease of proteins was very little in the carcass, tail and bone (ossa cruris). An increase of tissue collagen in protein depletion was found in the carcass, bone, tail, skin and liver, while muscle protein in the carcass was evidently lost at a later stage of protein depletion. The increase of calcium in the bone was parallel to the increase of collagen, indicating continuous growth of the bones in spite of protein depletion. These results may indicate that the young animals continuously synthesize collagens of their special tissues from other tissue proteins even with severe protein deficiency. The metabolic responses of body collagens to dietary protein depletion in young rats have been discussed and compared with those in adult rats reported previously.  相似文献   
976.
β-(1→3)-D-glucans with β-(1→6)-glycosidic linked branches produced by mushrooms, yeast and fungi are known to be an immune activation agent, and are used in anti-cancer drugs or health-promoting foods. In this report, we demonstrate that oral administration of Aureobasidium pullulans-cultured fluid (AP-CF) enriched with the β-(1→3),(1→6)-D-glucan exhibits efficacy to protect mice infected with a lethal titer of the A/Puerto Rico/8/34 (PR8; H1N1) strain of influenza virus. The survival rate of the mice significantly increased by AP-CF administration after sublethal infection of PR8 virus. The virus titer in the mouse lung homogenates was significantly decreased by AP-CF administration. No significant difference in the mRNA expression of inflammatory cytokines, and in the population of lymphocytes was observed in the lungs of mice administered with AP-CF. Interestingly, expression level for the mRNA of virus sensors, RIG-I (retinoic acid-inducible gene-I) and MDA5 (melanoma differentiation-associated protein 5) strongly increased at 5 hours after the stimulation of A. pullulans-produced purified β-(1→3),(1→6)-D-glucan (AP-BG) in murine macrophage-derived RAW264.7 cells. Furthermore, the replication of PR8 virus was significantly repressed by pre-treatment of AP-BG. These findings suggest the increased expression of virus sensors is effective for the prevention of influenza by the inhibition of viral replication with the administration of AP-CF.  相似文献   
977.

Background

Epithelial cell adhesion molecule (EpCAM)-based enumeration of circulating tumor cells (CTC) has prognostic value in patients with solid tumors, such as advanced breast, colon, and prostate cancer. However, poor sensitivity has been reported for non-small cell lung cancer (NSCLC). To address this problem, we developed a microcavity array (MCA) system integrated with a miniaturized device for CTC isolation without relying on EpCAM expression. Here, we report the results of a clinical study on CTCs of advanced lung cancer patients in which we compared the MCA system with the CellSearch system, which employs the conventional EpCAM-based method.

Methods

Paired peripheral blood samples were collected from 43 metastatic lung cancer patients to enumerate CTCs using the CellSearch system according to the manufacturer’s protocol and the MCA system by immunolabeling and cytomorphological analysis. The presence of CTCs was assessed blindly and independently by both systems.

Results

CTCs were detected in 17 of 22 NSCLC patients using the MCA system versus 7 of 22 patients using the CellSearch system. On the other hand, CTCs were detected in 20 of 21 small cell lung cancer (SCLC) patients using the MCA system versus 12 of 21 patients using the CellSearch system. Significantly more CTCs in NSCLC patients were detected by the MCA system (median 13, range 0–291 cells/7.5 mL) than by the CellSearch system (median 0, range 0–37 cells/7.5 ml) demonstrating statistical superiority (p = 0.0015). Statistical significance was not reached in SCLC though the trend favoring the MCA system over the CellSearch system was observed (p = 0.2888). The MCA system also isolated CTC clusters from patients who had been identified as CTC negative using the CellSearch system.

Conclusions

The MCA system has a potential to isolate significantly more CTCs and CTC clusters in advanced lung cancer patients compared to the CellSearch system.  相似文献   
978.
A Gram-negative, magnetotactic bacterium, Magnetospirillum magneticum AMB-1 produces nano-sized magnetic particles (BacMPs) in the cytoplasm. Although various applications of genetically engineered BacMPs have been demonstrated, such as immunoassay, ligand–receptor interaction or cell separation, by expressing a target protein on BacMPs, it has been difficult to express disulfide-bonded proteins on BacMPs due to lack of disulfide-bond formation in the cytoplasm. Here, we propose a novel dual expression system, called in vitro docking, of a disulfide-bonded protein on BacMPs by directing an immunoglobulin Fc-fused target protein to the periplasm and its docking protein ZZ on BacMPs. By in vitro docking, an scFv–Fc fusion protein was functionally expressed on BacMPs in the dimeric or trimeric form. Our novel disulfide-bonded protein expression system on BacMPs will be useful for efficient screening of potential ligands or drugs, analyzing ligand–receptor interactions or as a magnetic carrier for affinity purification.  相似文献   
979.
980.
The crystal structures of α-d-glucopyranosyl β-d-psicofuranoside and α-d-galactopyranosyl β-d-psicofuranoside were determined by a single-crystal X-ray diffraction analysis, refined to R1 = 0.0307 and 0.0438, respectively. Both disaccharides have a similar molecular structure, in which psicofuranose rings adopt an intermediate form between 4E and 4T3. Unique molecular packing of the disaccharides was found in crystals, with the molecules forming a layered structure stacked along the y-axis.  相似文献   
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