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401.
402.
Chen YY  Chou PY  Chien YC  Wu CH  Wu TS  Sheu MJ 《Phytomedicine》2012,19(8-9):768-778
Cancer metastasis is a primary cause of cancer death. Antrodia cinnamomea (A. cinnamomea), a medicinal mushroom in Taiwan, has been shown antioxidant and anticancer activities. In this study, we first observed that ethanol extract of fruiting bodies of A. cinnamomea (EEAC) exerted a concentration-dependent inhibitory effect on migration and motility of CL1-0 cells in the absence of cytotoxicity. The results of a gelatin zymography assay showed that A. cinnamomea suppressed the activity of matrix metalloproteinase (MMP)-2 and MMP-9 in a concentration-dependent manner. Western blot results demonstrated that treatment with A. cinnamomea decreased the expression of MMP-9 and MMP-2; while the expression of the endogenous inhibitors of these proteins, i.e., tissue inhibitors of MMP (TIMP-1 and TIMP-2) increased. Two major compounds from EEAC codycepin and zhankuic acid A alone and together inhibited MMP-9 and MMP-2 expressions. Further investigation revealed that A. cinnamomea suppressed the phosphorylation of p38, and JNK1/2. A. cinnamomea also suppressed the expressions of PI3K and phosphorylation of AKT. This is the first report confirming the anti-migration activity of this potentially beneficial mushroom against human lung adenocarcinoma CL1-0.  相似文献   
403.
404.

Objective

This study assessed the diagnostic performance and prognostic properties of C-reactive protein (CRP), copeptin and cortisol in individuals with sickle cell anaemia (SCA).

Design

Prospective case-control study

Methods

Sixty consecutive SCA subjects (18–40 years) comprising 30 subjects in the steady state and 30 subjects in vaso-occlusive crisis (VOC) were recruited into this study. Thirty (30) apparently healthy individuals with HbAA genotype served as controls. ELISA was used for the determination of serum levels of copeptin, CRP and cortisol. Data obtained were statistically analyzed using the Student’s t-test and Mann Whitney U as appropriate and P<0.05 was considered significant.

Results

SCA subjects in VOC had significantly lower copeptin level and significantly higher CRP level compared with controls. However, serum levels of copeptin, cortisol and CRP were significantly higher in SCA subjects in VOC compared with SCA subjects in steady state. Furthermore, CRP had the widest Area under the ROC curve (AUROC) than copeptin and cortisol. No significant difference was observed in the levels of copeptin, CRP and cortisol when SCA subjects in VOC who were hospitalized for less ≤5 days were compared with subjects who had longer stays.

Conclusion

It could be concluded that C-reactive protein has a superior diagnostic performance for vaso-occlusive crisis in individuals with sickle cell anaemia and that C-reactive protein, cortisol and copeptin are not good prognostic markers in SCA subjects in vaso-occlusive crisis.  相似文献   
405.
Chloroquine (CQ) is an antimalaria drug that has been used in clinical practice for several decades. One serious complication of CQ treatment is the macular retinopathy caused by the disruption of the retinal pigmented epithelium, leading to vision loss. Little is known about how CQ affects retinal pigmented epithelium. In this study, we found that cell proliferation was reduced by CQ treatment in time and dose-dependent manners. No obvious cell death was detected; however, what was observed instead was G0/G1 arrest during which primary cilium started to grow in the presence of CQ. Pharmacological inhibition of primary cilium formation led to a reduction of cell viability suggesting that CQ-induced primary cilium protected cells from death. In addition to cell growth, with the CQ treatment the retina pigmented epithelium (RPE) cells less flattened with the spindle-like protrusion. When checking the microtubule networks, the microtubule nucleation activity was disrupted in the presence of CQ. The level of p150 glued, the largest subunit of dynactin, was reduced in CQ-treated RPE1 cells, and depletion of p150 glued resulted in a phenotype reminiscent of CQ-treated cells. Thus, CQ treatment reduced the expression of p150 glued, leading to reduced S phase entry and defective microtubule nucleation.  相似文献   
406.
Cofilin is an actin-associated protein that belongs to the actin depolymerization factor/cofilin family and is important for regulation of actin dynamics. Cofilin can import actin monomers into the nucleus under certain stress conditions, however the biological effects of nuclear transport are unclear. In this study, we found that over-expression of cofilin led to increased radiation sensitivity in human non-small lung cancer H1299 cells. Cell survival as determined by colony forming assay showed that cells over-expressing cofilin were more sensitive to ionizing radiation (IR) than normal cells. To determine whether the DNA repair capacity was altered in cofilin over-expressing cells, comet assays were performed on irradiated cells. Repair of DNA damage caused by ionizing radiation was detected in cofilin over-expressing cells after 24 h of recovery. Consistent with this observation, the key components for repair of DNA double-strand breaks, including Rad51, Rad52, and Ku70/Ku80, were down-regulated in cofilin over-expressing cells after IR exposure. These findings suggest that cofilin can influence radiosensitivity by altering DNA repair capacity.  相似文献   
407.
Triflavin, an Arg-Gly-Asp (RGD)-containing snake venom peptide, inhibits B16-F10 mouse melanoma cell adhesion to extracellular matrices, e.g., fibronectin, vitronectin, fibrinogen, and collagen type I. In this study, GRGDS inhibits B16-F10 mouse melanoma cell adhesion to immobilized triflavin in a dose-dependent manner. In addition, flow-cytometric analysis and the fluorescence staining method in which FITC-triflavin is utilized as a binding ligand were used. GRGDS inhibits the binding of FITC-triflavin to B16-F10 cells. Additionally, the above results suggest that triflavin directly binds to its receptors expressed on B16-F10 cell surface primarily via its RGD sequence, there-by inhibiting B16-F10 cell adhesion to extracellular matrices.  相似文献   
408.
Na+- and CA2+-sensitive microelectrodes were used to measure intracellular Na+ and Ca2+ activities (alpha iCa) of sheep ventricular muscle and Purkinje strands to study the interrelationship between Na+ and Ca2+ electrochemical gradients (delta muNa and delta muCa) under various conditions. In ventricular muscle, alpha iNa was 6.4 +/- 1.2 mM and alpha iCa was 87 +/- 20 nM ([Ca/+] = 272 nM). A graded decrease of external Na+ activity (alpha oNa) resulted in decrease of alpha iNa, and increase of alpha iCa. There was increase of twitch tension in low- alpha oNa solutions, and occasional increase of resting tension in 40% alpha oNa. Increase of external Ca2+ (alpha oCa) resulted in increase of alpha iCa and decrease of alpha iNa. Decrease of alpha oCa resulted in decrease of alpha iCa and increase of alpha iNa. The apparent resting Na-Ca energy ratio (delta muCa/delta muNa) was between 2.43 and 2.63. When the membrane potential (Vm) was depolarized by 50 mM K+ in ventricular muscle, Vm depolarized by 50 mV, alpha iNa decreased, and alpha iCa increased, with the development of a contracture. The apparent energy coupling ratio did not change with depolarization. 5 x 10(-6) M ouabain induced a large increase in alpha iNa ad alpha iCa, accompanied by an increase in twitch and resting tension. Under the conditions we have studied, delta muNa and delta muCa appeared to be coupled and n was nearly constant at 2.5, as would be expected if the Na-Ca exchange system was able to set the steady level of alpha iCa. Tension threshold was about 230 nM alpha iCa. The magnitude of twitch tension was directly related to alpha iCa.  相似文献   
409.
Aged cardiomyocytes develop a mismatch between energy demand and supply, the severity of which determines the onset of heart failure, and become prone to undergo cell death. The FoF1‐ATP synthase is the molecular machine that provides >90% of the ATP consumed by healthy cardiomyocytes and is proposed to form the mitochondrial permeability transition pore (mPTP), an energy‐dissipating channel involved in cell death. We investigated whether aging alters FoF1‐ATP synthase self‐assembly, a fundamental biological process involved in mitochondrial cristae morphology and energy efficiency, and the functional consequences this may have. Purified heart mitochondria and cardiomyocytes from aging mice displayed an impaired dimerization of FoF1‐ATP synthase (blue native and proximity ligation assay), associated with abnormal mitochondrial cristae tip curvature (TEM). Defective dimerization did not modify the in vitro hydrolase activity of FoF1‐ATP synthase but reduced the efficiency of oxidative phosphorylation in intact mitochondria (in which membrane architecture plays a fundamental role) and increased cardiomyocytes’ susceptibility to undergo energy collapse by mPTP. High throughput proteomics and fluorescence immunolabeling identified glycation of 5 subunits of FoF1‐ATP synthase as the causative mechanism of the altered dimerization. In vitro induction of FoF1‐ATP synthase glycation in H9c2 myoblasts recapitulated the age‐related defective FoF1‐ATP synthase assembly, reduced the relative contribution of oxidative phosphorylation to cell energy metabolism, and increased mPTP susceptibility. These results identify altered dimerization of FoF1‐ATP synthase secondary to enzyme glycation as a novel pathophysiological mechanism involved in mitochondrial cristae remodeling, energy deficiency, and increased vulnerability of cardiomyocytes to undergo mitochondrial failure during aging.  相似文献   
410.
Chuang CH  Sheu BS  Huang AH  Yang HB  Wu JJ 《Helicobacter》2002,7(5):310-316
Aim. To test whether vitamin C and E supplements to triple therapy can improve the Helicobacter pylori eradication rate and gastric inflammation. Methods. A total of 104 H. pylori‐infected patients were randomized to receive: either lansoprazole, amoxicillin, and metronidazole twice daily for 1 week (triple‐only group) or lansoprazole, amoxicillin, metronidazole plus vitamin C (250 mg) and vitamin E (200 mg) twice daily for 1 week, followed immediately by vitamin C and E once daily for 6 consecutive weeks (triple‐plus‐vitamin group). Eight weeks after the completion of triple therapy, patients were assessed for the effectiveness of H. pylori eradication. The severity of gastric inflammation in histology was assessed for the acute and chronic inflammation scores. Results. Intention‐to‐treat and per‐protocol eradication rates were 59.1% and 64.4% in the triple‐only group, and 40% and 44% in the triple‐plus‐vitamin group. In the patients infected with metronidazole susceptible isolates, the triple‐only group had a higher intention‐to‐treat eradication rate than those in the triple‐plus‐vitamin group (80% vs. 53.1%, p < .01). However, for the metronidazole resistance isolates, the intention‐to‐treat eradication rates between the two groups were not different (26.3% vs. 21.7%, p = NS). The improvements of both acute and chronic inflammation scores in histology were not different between the two groups. Conclusion. Adding vitamin C and E to triple therapy cannot improve the H. pylori eradication rate and gastric inflammation. For patients with metronidazole susceptible strain infection, adding these vitamins may even reduce the eradication rate of triple therapy.  相似文献   
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