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As an attempt to identify bioactive natural products with anti-inflammatory activity, we evaluated the effects of the methanol extract of the semen of Xanthium strumarium L. (MEXS) on lipopolysaccharide (LPS)-induced nitric oxide (NO), prostaglandin E2 (PGE2) and tumor necrosis factor-alpha (TNF-alpha) production in RAW 264.7 cells. Our data indicate that MEXS is a potent inhibitor of NO, PGE2 and TNF-alpha production. Consistent with these findings, the expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein and iNOS, COX-2 and TNF-alpha mRNA were down-regulated in a concentration-dependent manner. Furthermore, MEXS inhibited nuclear factor kappa B (NF-kappaB) DNA binding activity and the translocation of NF-kappaB to the nucleus by blocking the degradation of inhibitor of kappa B-alpha (IkappaB-alpha). We further evaluated the anti-inflammatory and anti-nociceptive activities of MEXS in vivo. MEXS (100, 200 mg/kg/d, p.o.) reduced acute paw edema induced by carrageenin in rats, and showed analgesic activities in an acetic acid-induced abdominal constriction test and a hot plate test in mice. Thus, our study suggests that the inhibitions of iNOS, COX-2 expression, and TNF-alpha release by the methanol extract of the semen of Xanthium strumarium L. are achieved by blocking NF-kappaB activation, and that this is also responsible for its anti-inflammatory effects.  相似文献   
23.
Kang HJ  Kang YJ  Lee YM  Shin HH  Chung SJ  Kang S 《Biomaterials》2012,33(21):5423-5430
We genetically introduced the Fc-binding peptide (FcBP) into the loop of a self-assembled protein cage, ferritin, constituting four-fold symmetry at the surface to use it as a modular delivery nanoplatform. FcBP-presenting ferritin (FcBP-ferritin) formed very stable non-covalent complexes with both human and rabbit IgGs through the simple molecular recognition between the Fc region of the antibodies and the Fc-binding peptide clusters inserted onto the surface of FcBP-ferritin. This approach realized orientation-controlled display of antibodies on the surfaces of the protein cages simply by mixing without any complicated chemical conjugation. Using trastuzumab, a human anti-HER2 antibody used to treat patients with breast cancer, and a rabbit antibody to folate receptor, along with fluorescently labeled FcBP-ferritin, we demonstrated the specific binding of these complexes to breast cancer cells and folate receptor over-expressing cells, respectively, by fluorescent cell imaging. FcBP-ferritin may be potentially used as modular nanoplatforms for active targeted delivery vehicles or molecular imaging probes with a series of antibodies on demand.  相似文献   
24.
We show here that Ca(2+) and reactive oxygen species (ROS) are involved in the up-regulation of c-Jun NH(2)-terminal kinase 1 (JNK1) activity during apoptosis induced by ginsenoside Rh2 (G-Rh2) in HeLa, MCF10A-ras, and MCF7 cells. Addition of antioxidants such as N-acetyl-l-cysteine or catalase attenuates G-Rh2-induced ROS generation, JNK1 activation, and apoptosis. The overexpression of catalase down-regulates caspase-3 and JNK1 activities. G-Rh2 treatment of cells results in mitochondrial depolarization, second mitochondrial activator of caspase release, and translocation of Bax into the mitochondria, and these events are inhibited by antioxidants. Ca(2+) is also involved in mitochondrial depolarization during G-Rh2-induced apoptosis. These results suggest that ROS and Ca(2+) are important signaling intermediates leading to stress-activated protein kinase/extracellular signal-regulated kinase kinase 1/JNK1 activation and depolarization of the mitochondrial membrane potential in G-Rh2-induced apoptosis.  相似文献   
25.
A model incorporating the direct and indirect effects of parental monitoring on adolescent alcohol use was evaluated by applying structural equation modeling (SEM) techniques to data on 4,765 tenth-graders in the 2001 Monitoring the Future Study. Analyses indicated good fit of hypothesized measurement and structural models. Analyses supported both direct and indirect effects of parental monitoring on adolescent alcohol use. Peer influence, perceived alcohol norms, and conventional bonds mediated the relationship between parental monitoring and adolescent alcohol use. Results suggest parental involvement and proactive parenting skills as critical components of prevention and intervention programs that target adolescent alcohol use.  相似文献   
26.

Background

Gastric cancer with lymphoid stroma (GCLS) is pathologically characterized by poorly developed tubular structures with a prominent lymphocytic infiltration. Its clinical and prognostic features differ in patients positive and negative for Epstein–Barr virus (EBV) infection. This study analyzed the expression of programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-L1), and the density of tumor-infiltrating lymphocytes (TILs) including CD3+ and CD8+ T cells, as well as their prognostic significance in patients with GCLS.

Methods

The study included 58 patients with GCLS (29 EBV+ and 29 EBV?) who underwent curative resection. Expression of CD3, CD8, PD-1, and PD-L1 in tumor cells and TILs was analyzed using a quantitative multispectral imaging system (Opal?), with these results validated by immuno-histochemical assays for PD-L1 on whole slide sections.

Results

The proportion of tumors overexpressing PD-L1 (31.0 vs. 0%, P = 0.002), TIL density (4548 vs. 2631/mm2, P < 0.001), and intra-tumoral CD8+ T-cell density (2650 vs. 1060/mm2, P < 0.001) were significantly higher in EBV+ than in EBV? GCLS. In addition, CD8+/CD3+ T-cell ratio was higher in EBV+ than in EBV? GCLS (55.3 vs. 35.8%, P < 0.001). Lower TIL density, defined as < 1350/mm2, was a significant negative factor of survival.

Conclusions

Despite histopathological similarity, quantitative multispectral imaging revealed differences in the tumor immune micro-environment between EBV+ and EBV? GCLS, indicating that the underlying pathogenesis differs in these two disease entities. TIL density may be a prognostic marker in patients with GCLS.
  相似文献   
27.
Maternal serum levels of VCAM-1, ICAM-1 and E-selectin in preeclampsia   总被引:1,自引:0,他引:1  
Endothelial dysfunction is thought to be a central pathogenic feature in preeclampsia on the basis of elevated adhesion molecules. The aim of the present study was to compare the levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1) and E-selectin (sE-selectin) in sera of normal and preeclamptic pregnancies. We studied the serum levels of sVCAM-1, sICAM-1 and sE-selectin in normal pregnant women (n=63), mild preeclampsia (n=33) and severe preeclampsia (n=82). Concentrations of soluble adhesion molecules were determined with enzyme-linked immunoassay (ELISA). Serum concentrations of sVCAM-1 were significantly higher in both mild (p=0.004) and severe preeclampsia (p=0.000) than normal pregnancy. There were also significant differences in sVCAM- 1 levels between mild and severe preeclampsia (p=0.002). sICAM-1 levels of severe preeclampsia were statistically different from those of normal pregnancy (p=0.038). Levels of sE-selectin were elevated in both mild (p=0.011) and severe preeclampsia (p=0.000) compared to normal pregnancy, but no statistical difference between the mild and severe preeclampsia (p=0.345). These results suggest that all three soluble adhesion molecules are increased in severe preeclampsia, and sVCAM-1 among them may be useful in predicting the severity of preeclampsia.  相似文献   
28.
The intertidal copepod, Tigriopus japonicus has been recognized as a potential model species for marine pollution toxicity testing. Toxicity ranges of several biocides, endocrine-disrupting chemicals (EDCs), and trace metals are known in T. japonicus. A large number of expressed sequence tags (ESTs) and genomic DNA are also sequenced from T. japonicus. In this study, expression of ten glutathione S-transferase (GST) genes was studied in the copepods exposed to trace metals. Expression of these genes was also studied against exposure to hydrogen peroxide (H(2)O(2)) used as a positive control with prooxidant activity. Of all genes, expression of GST-Sigma (GSTS) was highly upregulated in H(2)O(2) as well as trace metal-exposed copepods. In the time-course study, expression of GSTS mRNA was more consistent compared to other GSTs such as GST-Omega, GST-Delta1, GST-Theta3 or microsomal GST1 (mGST1). GSTS is predominantly reported from the insects. Coupled with the previous study of the in vitro antioxidant role of T. japonicus GSTS, these findings imply an antioxidant role for GSTS and highlight its importance as a biomarker of exposure to trace metals in T. japonicus. However, further validation and field trials would be necessary to propose GSTS gene expression as biomarker of exposure to trace metals, as for some trace metals such as silver the response was not consistent in concentration and time-series exposure experiments.  相似文献   
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30.
Kunde SS  Roede JR  Vos MB  Orr ML  Go YM  Park Y  Ziegler TR  Jones DP 《Nutrients》2011,3(11):987-1002
Fructose-sweetened liquid consumption is associated with fatty liver and oxidative stress. In rodent models of fructose-mediated fatty liver, protein consumption is decreased. Additionally, decreased sulfur amino acid intake is known to cause oxidative stress. Studies were designed to test whether oxidative stress in fructose-sweetened liquid-induced fatty liver is caused by decreased ad libitum solid food intake with associated inadequate sulfur amino acid intake. C57BL6 mice were grouped as: control (ad libitum water), fructose (ad libitum 30% fructose-sweetened liquid), glucose (ad libitum 30% glucose-sweetened water) and pair-fed (ad libitum water and sulfur amino acid intake same as the fructose group). Hepatic and plasma thiol-disulfide antioxidant status were analyzed after five weeks. Fructose- and glucose-fed mice developed fatty liver. The mitochondrial antioxidant protein, thioredoxin-2, displayed decreased abundance in the liver of fructose and glucose-fed mice compared to controls. Glutathione/glutathione disulfide redox potential (E(h)GSSG) and abundance of the cytoplasmic antioxidant protein, peroxiredoxin-2, were similar among groups. We conclude that both fructose and glucose-sweetened liquid consumption results in fatty liver and upregulated thioredoxin-2 expression, consistent with mitochondrial oxidative stress; however, inadequate sulfur amino acid intake was not the cause of this oxidative stress.  相似文献   
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