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101.

Background/aims

TEC, a member of the TEC family of non-receptor type protein tyrosine kinases, has recently been suggested to play a role in hepatocyte proliferation and liver regeneration. This study aims to investigate the putative mechanisms of TEC kinase regulation of hepatocyte differentiation, i.e. to explore which signaling pathway TEC is involved in, and how TEC is activated in hepatocyte after hepatectomy and hepatocyte growth factor (HGF) stimulation.

Methods

We performed immunoprecipitation (IP) and immunoblotting (IB) to examine TEC tyrosine phosphorylation after partial hepatectomy in mice and HGF stimulation in WB F-344 hepatic cells. The TEC kinase activity was determined by in vitro kinase assay. Reporter gene assay, antisense oligonucleotide and TEC dominant negative mutant (TECKM) were used to examine the possible signaling pathways in which TEC is involved. The cell proliferation rate was evaluated by 3H-TdR incorporation.

Results

TEC phosphorylation and kinase activity were increased in 1 h after hepatectomy or HGF treatment. TEC enhanced the activity of Elk and serum response element (SRE). Inhibition of MEK1 suppressed TEC phosphorylation. Blocking TEC activity dramatically decreased the activation of Erk. Reduced TEC kinase activity also suppressed the proliferation of WB F-344 cells. These results suggest TEC is involved in the Ras-MAPK pathway and acts between MEK1 and Erk.

Conclusions

TEC promotes hepatocyte proliferation and regeneration and is involved in HGF-induced Erk signaling pathway.  相似文献   
102.
We have examined the photobehavior of a set of isomers of 2-pyranone-annulated stilbenes (6-styrylcoumarin , 7-styrylcoumarin , 4-methyl-6-styrylcoumarin , and 4-methyl-7-styrylcoumarin, ) in their crystalline phases. While the cis isomers of undergo cis-->trans photoisomerizations in the solid state, cis- and the trans isomers of do not; the trans isomer of undergoes photo-induced intermolecular reactions. Solution-state irradiations of the trans isomers of lead to the cis isomers quite readily, as does cis- lead to trans-, which suggests that the absence of geometric isomerization of the trans isomers and the lack of reactivity of cis- in the solid state are due to molecular packing effects. X-Ray crystal structural analyses of reveal interesting conformational preferences for the styrenic moieties and differences in the total 'free' volumes within the lattices, but neither factor explains satisfactorily why some of the molecules undergo geometric isomerizations in their single crystals and others do not. Using the PLATON program, we have located the sizes and positions of 'void volumes' within the crystal lattices, and identified trajectories necessary for atomic motions to lead to geometric isomerizations to understand the reactivities of . The voids in the reactive cis isomers of crystals are located along the trajectories needed for geometric isomerization. The relevant voids in the crystals of cis- and the trans isomers of and (the non-isomerizing molecules for which suitable crystals could be grown for X-ray analyses) are located along a trajectory that does not permit isomerization. We hypothesize that the classical momentum gained from the initial motions that are facilitated due to the voids in the crystals of the cis isomers of , as well as the heat dissipated to the local environment by internal conversions and vibronic cascade of the Franck-Condon states, helps to drive the system over potential energy barriers that would not be possible otherwise. Cis- and the trans isomers of and , as well as other examples from the literature in which geometric isomerizations do or do not occur in the solid state, also follow the predictions based upon the PLATON analyses. On these bases, it is suggested that the methodology described may be generally applicable for predicting when geometric isomerizations (and possibly other reactive processes) in crystalline materials will occur.  相似文献   
103.
Human growth hormone was conjugated to a carrier aldolase antibody, using a novel linker by connecting a disulphide bond in growth hormone to a lysine-94 amine located on the Fab arm of the antibody. The resulting CovX body showed reduced affinity towards human growth hormone receptor, reduced cell-based activity, but improved pharmacodynamic properties. We have demonstrated that this CovX-body, given once a week, showed comparable activity as growth hormone given daily in an in vivo hypophysectomized rat model.  相似文献   
104.
105.
We report the discovery and preliminary SAR studies of a series of structurally novel benzotriazine core based small molecules as inhibitors of Src kinase. To the best of our knowledge, benzotriazine template based compounds have not been reported as kinase inhibitors. The 3-(2-(1-pyrrolidinyl)ethoxy)phenyl analogue (43) was identified as one of the most potent inhibitors of Src kinase.  相似文献   
106.
A series of 1,2,4-trisubstituted 5-imidazolinone derivatives were synthesized by Erlenmeyer condensation of benzoylglycine (hippuric acid) with different aldehydes in the presence of sodium acetate and acetic anhydride. The derivatives of the compounds were prepared by condensation of some known sulpha drugs with 5-oxazolone derivatives. The anticonvulsant activity of the compounds was determined by the protection of pentylenetetrazole-induced convulsions that was ranged from 10 to 60%. The compounds with p-OCH?, p-OH and o-Cl substitutions in the phenyl ring on 4(th) position of the imidazolinone ring exhibited good anticonvulsant activity. In silico metabolic and toxicity studies showed that all the compounds in the series are not likely to exhibit toxicity except the compounds IIIa, IIIb, VIa and VIb, that is predicted to show 29% mutagenicity and 53% irritation in comparison to the other compounds. The predicted lethal effect and hERG toxicity of the compounds showed that IIa, IVa, Va and Vb might be toxic at higher concentrations. The results successfully establish the synthesized imidazolinone derivatives as novel compounds with anticonvulsant properties, low predicted cardiotoxicity and lethal effects thus can be promising leads for further development as novel anticonvulsants.  相似文献   
107.
Pancreatic cancer (PC) is a lethal malignancy primarily driven by activated Kras mutations and characterized by the deregulation of several genes including mucins. Previous studies on mucins have identified their significant role in both benign and malignant human diseases including PC progression and metastasis. However, the initiation of MUC expression during PC remains unknown because of lack of early stage tumor tissues from PC patients. In the present study, we have evaluated stage specific expression patterns of mucins during mouse PC progression in (KrasG12D;Pdx1-Cre (KC)) murine PC model from pancreatic intraepithelial neoplasia (PanIN) to pancreatic ductal adenocarcinoma (PDAC) by immunohistochemistry and quantitative real-time PCR. In agreement with previous studies on human PC, we observed a progressive increase in the expression of mucins particularly Muc1, Muc4 and Muc5AC in the pancreas of KC (as early as PanIN I) mice with advancement of PanIN lesions and PDAC both at mRNA and protein levels. Additionally, mucin expression correlated with the increased expression of inflammatory cytokines IFN-γ (p?相似文献   
108.
The present study was to determine the efficacies of anti-parasitic activities of synthesized silver nanoparticles (Ag NPs) using stem aqueous extract of Cissus quadrangularis against the adult of hematophagous fly, Hippobosca maculata (Diptera: Hippoboscidae), and the larvae of cattle tick, Rhipicephalus (Boophilus) microplus (Acari: Ixodidae). Contact toxicity method was followed to determine the potential of parasitic activity. Twelve milliliters of stem aqueous extract of C. quadrangularis was treated with 88ml of 1mM silver nitrate (AgNO(3)) solution at room temperature for 30min and the resulting solution was yellow-brown color indicating the formation extracellular synthesis of Ag NPs. The synthesized Ag NPs were characterized with UV-visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscope (FESEM) and energy dispersive X-ray (EDX) spectroscopy. The synthesized Ag NPs were recorded by UV-visible spectrum at 420nm and XRD patterns showed the nanoparticles crystalline in nature. FTIR analysis confirmed that the bioreduction of Ag((+)) ions to Ag NPs were due to the reduction by capping material of plant extract. FESEM image of Ag NPs showed spherical and oval in shape. By using the Bragg's Law and Scherrer's constant, the average mean size of synthesized Ag NPs was 42.46nm. The spot EDX analysis showed the complete chemical composition of the synthesized Ag NPs. The mortality obtained by the synthesized Ag NPs from the C. quadrangularis was more effective than the aqueous extract of C. quadrangularis and AgNO(3) solution (1mM). The adulticidal activity was observed in the aqueous extract, AgNO(3) solution and synthesized Ag NPs against the adult of H. maculata with LC(50) values of 37.08, 40.35 and 6.30mg/L; LC(90) values of 175.46, 192.17 and 18.14mg/L and r(2) values of 0.970, 0.992 and 0.969, respectively. The maximum efficacy showed in the aqueous extract, AgNO(3) solution and synthesized Ag NPs against the larvae of R. (B.) microplus with LC(50) values of 50.00, 21.72 and 7.61mg/L; LC(90) values of 205.12, 82.99 and 22.68mg/L and r(2) values of 0.968, 0.945and 0.994, respectively. The present study is the first report on antiparasitic activity of the experimental plant extract and synthesized Ag NPs. This is an ideal eco-friendly and inexpensive approach for the control of H. maculata and R. (B.) microplus.  相似文献   
109.

Introduction

5-Loxin® is a novel Boswellia serrata extract enriched with 30% 3-O-acetyl-11-keto-beta-boswellic acid (AKBA), which exhibits potential anti-inflammatory properties by inhibiting the 5-lipoxygenase enzyme. A 90-day, double-blind, randomized, placebo-controlled study was conducted to evaluate the efficacy and safety of 5-Loxin® in the treatment of osteoarthritis (OA) of the knee.

Methods

Seventy-five OA patients were included in the study. The patients received either 100 mg (n = 25) or 250 mg (n = 25) of 5-Loxin® daily or a placebo (n = 25) for 90 days. Each patient was evaluated for pain and physical functions by using the standard tools (visual analog scale, Lequesne''s Functional Index, and Western Ontario and McMaster Universities Osteoarthritis Index) at the baseline (day 0), and at days 7, 30, 60 and 90. Additionally, the cartilage degrading enzyme matrix metalloproteinase-3 was also evaluated in synovial fluid from OA patients. Measurement of a battery of biochemical parameters in serum and haematological parameters, and urine analysis were performed to evaluate the safety of 5-Loxin® in OA patients.

Results

Seventy patients completed the study. At the end of the study, both doses of 5-Loxin® conferred clinically and statistically significant improvements in pain scores and physical function scores in OA patients. Interestingly, significant improvements in pain score and functional ability were recorded in the treatment group supplemented with 250 mg 5-Loxin® as early as 7 days after the start of treatment. Corroborating the improvements in pain scores in treatment groups, we also noted significant reduction in synovial fluid matrix metalloproteinase-3. In comparison with placebo, the safety parameters were almost unchanged in the treatment groups.

Conclusion

5-Loxin® reduces pain and improves physical functioning significantly in OA patients; and it is safe for human consumption. 5-Loxin® may exert its beneficial effects by controlling inflammatory responses through reducing proinflammatory modulators, and it may improve joint health by reducing the enzymatic degradation of cartilage in OA patients.

Trail Registration

(Clinical trial registration number: ISRCTN05212803.)  相似文献   
110.
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