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41.
42.
Nagao T  Tanino T  Iwaki M 《Chirality》2003,15(5):423-428
To determine the effect of arthritis on the disposition of flurbiprofen (FP) and its acyl glucuronide (FPG) as well as formation of covalent adducts with plasma protein, a pharmacokinetic study was carried out in adjuvant-induced arthritic (AA) rats. In control animals the pharmacokinetics of FP were stereoselective following intravenous bolus injection of rac-FP: (-)-(R)-FP showed higher plasma clearance (CL(tot)) and shorter mean residence time (MRT) compared to (+)-(S)-FP. The CL(tot) and clearance for the glucuronide formation (CL(glu)) of both enantiomers in AA rats were extremely increased compared to those in control rats. Increased total clearance in AA rats was due, at least in part, to a remarkable increase in the plasma unbound fraction of FP, consistent with a decrease in the plasma albumin level. The yield of covalent binding of FP to plasma protein in AA rats was less than that in controls, being consistent with the decrease in the plasma acyl glucuronide level.  相似文献   
43.
Activation of NADPH oxidase in Alzheimer's disease brains   总被引:5,自引:0,他引:5  
The present study is the first to show that superoxide (O(-)(2)) forming NADPH oxidase is activated in Alzheimer's disease (AD) brains by demonstrating the marked translocation of the cytosolic factors p47-phox and p67-phox to the membrane. In conjunction with a recent in vitro study showing that amyloid beta activates O(-)(2) forming NADPH oxidase in microglia, where these phox proteins are localized in this study, the present results suggest that, in AD, NADPH oxidase is activated in microglia, resulting in the formation of reactive oxygen species which can be toxic to neighboring neurons in AD.  相似文献   
44.

Purpose

Zoledronic acid (ZOL) is a nitrogen-containing bisphosphonate that induces osteoclast apoptosis and inhibits bone resorption by inhibiting the mevalonate pathway. Its benefit for the prevention of skeletal complications due to bone metastases has been established. However, the antitumor efficacy of ZOL, although suggested by multiple preclinical and clinical studies, has not yet been clinically proven. We performed the present randomized Phase 2 trial to investigate the antitumor effect of ZOL with chemotherapy (CT).

Methods

Asian patients with HER2-negative invasive breast cancer were randomly assigned to either the CT or CT+ZOL (CTZ) group. One hundred and eighty-eight patients were randomized to either the CT group (n = 95) or the CTZ group (n = 93) from March 2010 to April 2012, and 180 patients were assessed. All patients received four cycles of FEC100 (fluorouracil 500 mg/m2, epirubicin 100 mg/m2, and cyclophosphamide 500 mg/m2), followed by 12 cycles of paclitaxel at 80 mg/m2 weekly. ZOL (4 mg) was administered three to four times weekly for 7 weeks to the patients in the CTZ group. The primary endpoint was the pathological complete response (pCR) rate, which was defined as no invasive cancer in the breast tissue specimen. Safety was assessed in all patients who received at least one dose of the study drug.

Results

This randomized controlled trial indicated that the rates of pCR in CTZ group (14.8%) was doubled to CT group (7.7%), respectively (one-sided chi-square test, p = 0.068), though the additional efficacy of zoledronic acid was not demonstrated statistically. The pCR rate in postmenopausal patients was 18.4% and 5.1% in the CTZ and CT groups, respectively (one-sided Fisher’s exact test, p = 0.071), and that in patients with triple-negative breast cancer was 35.3% and 11.8% in the CTZ and CT groups, respectively (one-sided Fisher’s exact test, p = 0.112). Thus the addition of ZOL to neoadjuvant CT has potential anticancer benefits in postmenopausal patients and patients with triple-negative breast cancer. Further investigation is warranted.

Trial Registration

University Hospital Medical Information Network. UMIN000003261.  相似文献   
45.
ObjectiveTherapy‐induced senescent cancer cells increase the expression of the cyclin‐dependent kinase inhibitors p16Ink4a and p21Cip1/Waf1. Given that p21 regulates not only the cell cycle but also cell death, we investigated the roles of p21 in cell death using a p16‐negative A549 human lung adenocarcinoma cell line.MethodsSenescence was induced by doxorubicin (DXR) or pemetrexed (PEM). The protein expression of p21 was examined by immunoblot. Cell death, reactive oxygen species (ROS) and lipid peroxidation were determined by flow cytometry. ABT‐263 and ABT‐737 were used as senolytic drugs. In vivo growth of A549 cells with different levels of p21 and their sensitivity to PEM were examined in xenograft models.ResultsDXR‐induced senescent A549 cells increased the expression of cytoplasmic p21, and the sensitivity to ABT‐263 was augmented in p21‐knockout A549 (A549‐KOp21) cells. A similar senolytic effect was observed when PEM was combined with ABT‐737. PEM alone induced a higher level of non‐apoptotic cell death, ferroptosis, in A549‐KOp21 cells than in A549 cells. Although there was no difference in the level of lipid peroxidation, ROS levels were higher in PEM‐treated A549‐KOp21 cells than in PEM‐treated A549 cells. A loss of p21 increased the sensitivity of A549 cells to PEM both in vitro and in vivo. A clinical database analysis showed that CDKN1A high lung adenocarcinoma patients had a poorer prognosis compared to CDKN1A low patients.ConclusionCytoplasmic p21, which was increased in therapy‐induced senescent lung cancer cells, plays protective roles in senolysis and ferroptosis.

Doxorubicin or pemetrexed could induce senescence in p21‐expressing parental A549 cells and increase the expression of cytoplasmic p21. However, such drug‐induced senescent A549 cells were relatively resistant to apoptosis by senolytic drugs. By contrast, p21‐knockout A549 (A549‐KOp21) cells increased their sensitivity to senolytic drugs. On the other hand, pemetrexed induced a higher level of non‐apoptotic cell death, ferroptosis, in A549‐KOp21 cells than in A549 cells. These findings highlight the protective roles of cytoplasmic p21 against senolysis and ferroptosis in therapy‐induced senescent lung cancer cells.  相似文献   
46.
The methanolysis of soybean oil to produce a fatty acid methyl ester (ME, i.e., biodiesel fuel) was catalyzed by lipase-producing filamentous fungi immobilized on biomass support particles (BSPs) as a whole-cell biocatalyst in the presence of ionic liquids. We used four types of whole-cell biocatalysts: wild-type Rhizopus oryzae producing triacylglycerol lipase (w-ROL), recombinant Aspergillus oryzae expressing Fusarium heterosporum lipase (r-FHL), Candida antarctica lipase B (r-CALB), and mono- and diacylglycerol lipase from A. oryzae (r-mdlB). w-ROL gave the high yield of fatty acid methyl ester (ME) in ionic liquid [Emim][BF4] or [Bmim][BF4] biphasic systems following a 24 h reaction. While lipases are known to be severely deactivated by an excess amount of methanol (e.g. 1.5 Mequiv. of methanol against oil) in a conventional system, methanolysis successfully proceeded even with a methanol/oil ratio of 4 in the ionic liquid biphasic system, where the ionic liquids would work as a reservoir of methanol to suppress the enzyme deactivation. When only w-ROL was used as a biocatalyst for methanolysis, unreacted mono-glyceride remained due to the 1,3-positional specificity of R. oryzae lipase. High ME conversion was attained by the combined use of two types of whole-cell biocatalysts, w-ROL and r-mdlB. In a stability test, the activity of w-ROL was reduced to one-third of its original value after incubation in [Bmim][BF4] for 72 h. The stability of w-ROL in [Bmim][BF4] was greatly enhanced by cross-linking the biocatalyst with glutaraldehyde. The present study demonstrated that ionic liquids are promising candidates for use as the second solvent in biodiesel fuel production by whole-cell biocatalysts.  相似文献   
47.
Metabolic alterations associated with the induction of freezingtolerance by abscisic acid (ABA) were characterized by chemicalanalysis and by [U-l4C]sucrose partitioning into cellular constituentsin bromegrass (Bromus inermis Leyss cv. Manchar) cell suspensioncultures. ABA caused a significant elevation in dry matter,particularly in the fraction insoluble in 85% ethanol, thatwas highly correlated with enhanced frost tolerance. Cell walls,the largest component of the insoluble fraction, increased significantlyas frost tolerance increased throughout the ABA treatment period.ABA stimulated total [14C]sucrose uptake by cells from 7% onday 1 to 97% on day 7 compared to control cells. Partitioningstudies detected a significant increase in 14CO2 evolution at3, 5 and 7 days after ABA treatment and a significantly higherincorporation of [14C]sucrose into the ethanol insoluble fractionafter 5 and 7 days of treatment. Organic acid depletion in ABA-treatedcells was also highly correlated with the increase in hardiness.The concentration of total sugars was higher in ABA-treatedcells. The results indicate that most of the metabolic changesduring ABA-induced acclimation were similar to changes reportedfor cells acclimated in response to low temperature. 1Oregon Agricultural Experiment Station Technical Paper No.9052 2Present address: Department of Horticulture, University ofSaskatchewan, Saskatoon, Sask. Canada S7N 0W0 (Received November 1, 1989; Accepted March 13, 1990)  相似文献   
48.
The favorable prognosis of high-grade oligodendroglial tumor such as glioblastoma (GBM) with oligodendroglioma component (GBMO) has been suggested; however, the studies which examine the prognostic significance of oligodendroglial tumor were limited. In this study, we performed a histopathology-based reevaluation of 111 cases of high grade gliomas according to the latest World Health Organization (WHO), and compared the clinical outcomes between oligodendroglial tumors and pure astrocytic tumors. The survival analysis revealed that the patients with high grade oligodendroglial tumor including GBMO significantly indicated better prognosis compared to the patients with high grade pure astrocytic tumors (GBM and AA, anaplastic astrocytoma) as expected, and the obtained survival curves were almost identical to those from the patients with conventional Grade III or Grade IV tumors, respectively. Moreover, if the cases of oligodendroglial tumor were histopathologically excluded, the patients with AA exhibited extremely poor prognosis which was similar to that of GBM, suggesting that the histological identification of oligodendroglial tumor component, even partially, prescribe the prognosis of high grade glioma patients. This is the prominent report of retrospective clinicopathological analysis for high-grade gliomas throughout Grade III and IV, especially referring to the prognostic value of histological oligodendroglial tumor component; in addition, our results might offer an alternative aspect for the grading of high-grade astrocytic/oligodendroglial tumors.  相似文献   
49.
Quantifying soft-tissue tension around the hip joint during total hip arthroplasty remains difficult. In this study, a three-dimensional computer-aided design model was developed to clarify how component position in total hip arthroplasty contributes to the primary cause of posterior dislocation in cases of flexion, adduction and internal rotation. To better understand the influences of anteversion angle of the acetabular component, its effects on the primary causes of dislocations and the range of motion were investigated. Three different primary dislocation mechanisms were noted: impingement of the prosthetic femoral neck on the cup liner; impingement of the osseous femur on the osseous pelvis; and spontaneous dislocation caused by soft-tissue traction without impingement. Spontaneous dislocation could be detected by calculating hip forces at any thigh position using the computer-aided design model developed. In computer analysis, a transition from prosthetic impingement rate to osseous impingement rate occurred with increasing anteversion angle of the acetabular component. Spontaneous dislocation was detected at angles > 10° of anteversion of the acetabular component when flexion occurred with extreme adduction and internal rotation. This study demonstrated the possibility of spontaneous dislocation that results not from prosthetic or bony impingement but from muscle traction with increased range of motion.  相似文献   
50.
The role of inducible nitric oxide synthase (iNOS) in the progression of fibrosis during nonalcoholic steatohepatitis remains to be elucidated. This study examined the role of iNOS in the progression of fibrosis during steatohepatitis by comparing iNOS knockout (iNOS(-/-)) and wild-type (iNOS(+/+)) mice that were fed a high-fat diet. Severe fatty metamorphosis developed in the liver of iNOS(+/+) and iNOS(-/-) mice. Fibrotic changes were marked in iNOS(-/-) mice. Gelatin zymography showed that pro MMP-2 and pro MMP-9 protein expressions were more highly induced in iNOS(+/+) mice than in iNOS(-/-) mice. Active forms of MMP-2 and MMP-9 were clearly present only in the liver tissue of iNOS(+/+) mice. In situ zymography showed strong gelatinolytic activities in the liver tissue of iNOS(+/+) mice, but only spotty activity in iNOS(-/-)mice. iNOS may attenuate the progression of liver fibrosis in steatohepatitis, in part by inducing MMP-2 and MMP-9 expression and augmenting their activity.  相似文献   
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