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In this report, we examine the clinical safety and efficacy of NG440, a phytochemical-based antiinflammatory formula consisting of a combination of rho iso-alpha acids from hops, rosemary, and oleanolic acid. In a previous study, we demonstrated that NG440 significantly decreased pain by 50% in patients with osteoarthritis. Consistent with these data, results from a multicentre trial indicate that NG440 reduced pain scores in patients with joint discomfort, as measured by VAS (visual analog scale) methodology. As demonstrated in an ex vivo clinical study, these effects on pain relief may be due to reduced inflammatory cytokine production including lower prostaglandin E2 formation. Finally, strong data exist to suggest that NG440 is a safe formula for human consumption. Animal toxicity data revealed no adverse effects of NG440 at dosages < or =250 mg.kg-1.day-1 for 21 days. Furthermore, human trial data suggest that NG440 does not negatively impact cardiovascular and gastrointestinal markers normally affected by selective COX-2 enzyme inhibitors, including platelet function, blood pressure, blood cell count, or fecal calprotectin, a measure of gastrointestinal injury. In conclusion, NG440 may serve as a safe and efficacious alternative in some areas where specific COX-2 inhibitors have been traditionally used.  相似文献   
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We report the presence, in the mitochondrial DNA (mtDNA) of all of the sexual species of the salamander family Ambystomatidae, of a shared 240- bp intergenic spacer between tRNAThr and tRNAPro. We place the intergenic spacer in context by presenting the sequence of 1,746 bp of mtDNA from Ambystoma tigrinum tigrinum, describe the nucleotide composition of the intergenic spacer in all of the species of Ambystomatidae, and compare it to other coding and noncoding regions of Ambystoma and several other vertebrate mtDNAs. The nucleotide substitution rate of the intergenic spacer is approximately three times faster than the substitution rate of the control region, as shown by comparisons among six Ambystoma macrodactylum sequences and eight members of the Ambystoma tigrinum complex. We also found additional inserts within the intergenic spacers of five species that varied from 87-444 bp in length. The presence of the intergenic spacer in all sexual species of Ambystomatidae suggests that it arose at least 20 MYA and has been a stable component of the ambystomatid mtDNA ever since. As such, it represents one of the few examples of a large and persistent intergenic spacer in the mtDNA of any vertebrate clade.   相似文献   
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Background

Systemic inflammation may contribute to cachexia in patients with chronic obstructive pulmonary disease (COPD). In this longitudinal study we assessed the association between circulating C-reactive protein (CRP), tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6 levels and subsequent loss of fat free mass and fat mass in more than 400 COPD patients over three years.

Methods

The patients, aged 40–76, GOLD stage II-IV, were enrolled in 2006/07, and followed annually. Fat free mass and fat mass indexes (FFMI & FMI) were calculated using bioelectrical impedance, and CRP, TNF-α, IL-1ß, and IL-6 were measured using enzyme immunoassays. Associations with mean change in FFMI and FMI of the four inflammatory plasma markers, sex, age, smoking, FEV1, inhaled steroids, arterial hypoxemia, and Charlson comorbidity score were analyzed with linear mixed models.

Results

At baseline, only CRP was significantly (but weakly) associated with FFMI (r = 0.18, p < 0.01) and FMI (r = 0.27, p < 0.01). Univariately, higher age, lower FEV1, and use of beta2-agonists were the only significant predictors of decline in FFMI, whereas smoking, hypoxemia, Charlson score, and use of inhaled steroids predicted increased loss in FMI. Multivariately, high levels of TNF-α (but not CRP, IL-1ß or IL-6) significantly predicted loss of FFMI, however only in patients with established cachexia at entry.

Conclusion

This study does not support the hypothesis that systemic inflammation is the cause of accelerated loss of fat free mass in COPD patients, but suggests a role for TNF-α in already cachectic COPD patients.  相似文献   
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The objective of this study was to determine whether cells in G(0) phase are functionally distinct from those in G(1) with regard to their ability to respond to the inducers of DNA synthesis and to retard the cell cycle traverse of the G(2) component after fusion. Synchronized populations of HeLa cells in G(1) and human diploid fibroblasts in G(1) and G(0) phases were separately fused using UV-inactivated Sendai virus with HeLa cells prelabeled with [(3)H]ThdR and synchronized in S or G(2) phases. The kinetics of initiation of DNA synthesis in the nuclei of G(0) and G(1) cells residing in G(0)/S and G(1)/S dikaryons, respectively, were studied as a function of time after fusion. In the G(0)/G(2) and G(1)/G(2) fusions, the rate of entry into mitosis of the heterophasic binucleate cells was monitored in the presence of Colcemid. The effects of protein synthesis inhibition in the G(1) cells, and the UV irradiation of G(0) cells before fusion, on the rate of entry of the G(2) component into mitosis were also studied. The results of this study indicate that DNA synthesis can be induced in G(0)nuclei after fusion between G(0)- and S-phase cells, but G(0) nuclei are much slower than G(1) nuclei in responding to the inducers of DNA synthesis because the chromatin of G(0) cells is more condensed than it is in G(1) cells. A more interesting observation resulting from this study is that G(0) cells is more condensed than it is in G(1) cells. A more interesting observation resulting from this study is that G(0) cells differ from G(1) cells with regard to their effects on the cell cycle progression of the G(2) nucleus into mitosis. This difference between G(0) and G(1) cells appears to depend on certain factors, probably nonhistone proteins, present in G(1) cells but absent in G(0) cells. These factors can be induced in G(0) cells by UV irradiation and inhibited in G(1) cells by cycloheximide treatment.  相似文献   
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A promising area of novel anti-diabetic therapy involves identification of small molecule activators of the glucokinase enzyme to reduce blood glucose and normalize glucose stimulated insulin secretion. Herein, we report the identification and optimization of a series of 4-sulfonyl-2-pyridone activators. The activators were evaluated for in vitro biochemical activation and pharmacokinetic properties. As part of these efforts, a unique metabolic liability of the 4-sulfonyl-2-pyridone ring system was identified wherein this heterocycle readily undergoes conjugation with glutathione under non-enzymatic conditions.  相似文献   
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Structure-activity relationship (SAR) studies of 2-[3-di(and tri)fluoromethyl-5-arylpyrazol-1-yl]-5-methanesulfonylpyridine derivatives for canine COX enzymes are described. This led to the identification of 12a as a lead candidate for further progression. The in vitro and in vivo activity of 12a for the canine COX-2 enzyme as well as its in vivo efficacy and pharmacokinetic properties in dog are highlighted.  相似文献   
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We investigated in bile duct-ligated (BDL) and sham-operated control rats whether the frequent presence of essential fatty acid deficiency in cholestatic liver disease could be related to linoleic acid malabsorption, altered linoleic acid metabolism, or both. In plasma of BDL rats, the triene-to-tetraene ratio, a biochemical marker for essential fatty acid deficiency, was increased compared with controls (0.024 +/- 0.004 vs. 0.013 +/- 0.001; P < 0.05). Net and percentage of dietary linoleic acid absorbed were decreased in BDL rats compared with control rats (1.50 +/- 0.16 mmol/day and 81.3 +/- 3.3% vs. 2.08 +/- 0.07 mmol/day and 99.2 +/- 0.1%, respectively; each P < 0.001). At 24 h after [(13)C]linoleic acid administration, BDL rats had a similar ratio of plasma [(13)C]arachidonic acid to plasma [(13)C]linoleic acid concentration compared with control rats. Delta(6)-Desaturase activity was not significantly different in hepatic microsomes from control or BDL rats. At 3 h after [(13)C]linoleic acid administration, plasma appearance of [(13)C]linoleic acid and cumulative expiration of (13)CO(2) were decreased in BDL rats, compared with controls (by 54% and 80%, respectively). The present data indicate that the impaired linoleic acid status in cholestatic liver disease is mainly due to decreased net absorption and not to quantitative alterations in postabsorptive metabolism.  相似文献   
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