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91.
In female virgin Wistar rats, the effects of a cafeteria-diet induced obesity on blood amino acid levels and their distribution between plasma and blood cells have been studied in fed and 24-hour starved states. Cafeteria diet induced obesity provoked a decrease in total blood cell amino acid content, both in fed and starved situations when compared with controls. Whether is a causal factor for developing obesity due to imbalance in tissue amino acid supply for protein biosynthesis processes, or represents some signal related to hypothalamic control of feeding, or is a consequence of the obesity remains to be established.  相似文献   
92.
The objective of this study was to assess the impact of dietary obesity and acute starvation on the activity of placental enzymes involved in amino acid metabolism. Twenty-four hours starvation caused a significant fall (10%) in the foetal weight in rats fed standard diet, and this was associated with only modest changes in amino acid enzyme activities. In contrast, in obese rats, foetal weight was unaffected by acute starvation, and was accompanied by a reduced adenylate deaminase activity (24%) and lower ammonia concentrations (50%) in placentae of obese rats after 24h starvation. Thus obesity may confer a protective effect on the foetus growth during acute starvation of diminishing amino acid utilization.  相似文献   
93.
Alanine metabolism in 24 hour starved 20-day pregnant rats, following intravenously administered C14-alanine, in trace dose that does not affect the normal availability of this amino acid, has been studied. The steady state levels of alanine and glucose in blood, liver and skeletal muscle, together with the tissue glycogen, metabolites and amino acid composition pools, are given in both the maternal and foetal compartments compared with the virgin control rats. The utilization of alanine as a gluconeogenetic precursor is not increased in late pregnancy under 24-hour starvation and it depends on the lower blood substrate availability.  相似文献   
94.
Plasma amino acid concentrations were determined in virgin female rats, in pregnant rats (12 and 21 days after impregnation) and in 21-day foetuses. The total amino acid concentration in plasma decreases significantly with pregnancy, being lower at 12 than at 21 days. Alanine, glutamine+glutamate and other 'gluconeogenic' amino acids decrease dramatically by mid-term, but regain their original concentrations at the end of the pregnancy. With most other amino acids, mainly the essential ones, the trend is towards lower concentrations which are maintained throughout pregnancy. These data agree with known nitrogen-conservation schemes in pregnancy and with the important demands on amino acids provoked by foetal growth. In the 21-day foetuses, concentrations of individual amino acids are considerably higher than in their mothers, with high plasma foetal/maternal concentration ratios, especially for lysine, phenylalanine and hydroxy-proline, suggesting active protein biosynthesis and turnover. All other amino acids also have high concentration ratios, presumably owing to their requirement by the foetuses for growth. Alanine, glutamine+glutamate, asparagine+aspartate, glycine, serine and threonine form a lower proportion of the total amino acids in foetuses than in the virgin controls or pregnant rats, probably owing to their role primarily in energy metabolism in the adults. The results indicate that at this phase of foetal growth, the placental amino acid uptake is considerable and seems to be higher than immediately before birth.  相似文献   
95.

Background

Calprotectin is a biomarker of disease activity in rheumatoid arthritis (RA) and psoriatic arthritis (PsA) and predicts relapse in juvenile idiopathic arthritis. Higher drug trough serum levels are associated with a good response in patients treated with tumor necrosis factor inhibitors (TNFi). Power Doppler ultrasound synovitis is predictive of relapse and structural damage progression in patients in clinical remission. The purpose of this study was to analyze the accuracy of serum calprotectin levels, drug trough serum levels (TSL), and power Doppler (PD) activity as predictors of relapse in RA and PsA patients in remission or with low disease activity receiving TNFi.

Methods

This was a longitudinal, prospective, 1-year single-center study of 103 patients (47 RA, 56 PsA) receiving TNFi in remission or with low disease activity (28-joint Disease Activity Score (DAS28)?≤?3.2). The predictive value of serum calprotectin, TNFi TSL, and PD were assessed using receiver operating characteristic (ROC) analyses. To illustrate the predictive performance of calprotectin, TNFi TSL, and PD score, Kaplan-Meier curves were constructed from baseline to relapse. Associations between baseline factors and relapse were determined using Cox regression models. Multivariate models were constructed to analyze the effect of covariates and to fully adjust the association between calprotectin, TNFi TSL, and PD score with relapse. A generalized estimating equation model with an identity link for longitudinal continuous outcomes was used to assess the effect of covariates on TNFi TSL.

Results

Ninety-five patients completed 1 year of follow-up, of whom 12 experienced a relapse. At baseline, relapsers had higher calprotectin levels, lower TNFi TSL, and higher PD activity than nonrelapsers. ROC analysis showed calprotectin fully predicted relapse (area under the curve (AUC)?=?1.00). TNFi TSL and PD had an AUC of 0.790 (95% confidence interval (CI) 0.691–0.889) and 0.877 (95% CI 0.772–0.981), respectively. Survival analyses and log rank tests showed significant differences between groups according to calprotectin serum levels (p?<?0.001), TNFi TSL (p?=?0.004), and PD score (p?<?0.001). Univariate Cox regression models showed that time-to-remission/low disease activity (hazard ratio (HR)?=?1.17, p?<?0.001), calprotectin levels (HR?=?2.38, p?<?0.001), TNFi TSL (HR?=?0.47, p?=?0.018), and PD score (HR?=?1.31, p?<?0.001) were significantly associated with disease relapse. In the multivariate analysis, only baseline calprotectin levels independently predicted disease relapse (HR?=?2.41, p?=?0.002). The generalized estimating equation analysis showed that only disease activity by DAS28-erythrocyte sedimentation rate (ESR) was significantly associated with longitudinal changes in TNFi TSL (regression coefficient 0.26 (0.0676 to 0.0036), p?=?0.001).

Conclusion

Time-to-remission/low disease activity, calprotectin serum levels, TNFi TSL, and PD score were significantly associated with disease relapse. However, only baseline calprotectin serum levels independently predicted disease relapse in RA and PsA patients under TNFi therapy.
  相似文献   
96.
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98.
Rat body size and tissue composition changes from pre-weaning to three months age resulted from voluntary hyperphagia triggered by offering a cafeteria diet. The effects of a 24 hour starvation period in both cafeteria and chow fed controls were compared. Obesity develops earlier in females than in males. This difference is related to the growth patterns in both sexes. Obesity occurs at the stages of development when growth rate decreases. Cafeteria fed female rats attained a 32% greater weight than their controls, with lumbar adipose cords that were 4 times heavier and brown interscapular adipose tissue 2 times heavier than controls. The overall cafeteria fed versus chow fed rat differences in the effects of a 24 hour starvation, were minor but less liver glycogen and much more skeletal muscle lipids were mobilized in the cafeteria fed rats than in controls.  相似文献   
99.
100.
BackgroundPrimary care (PC) patients have difficulties in committing to and incorporating primary prevention and health promotion (PP&HP) activities into their long-term care. We aimed to re-interpret, for the first time, qualitative findings regarding factors affecting PC patients'' acceptance of PP&HP activities.ConclusionsSeveral factors affect PP&HP. This must be taken into account when designing PP&HP activities if they are to be successfully implemented and maintained in routine practice.  相似文献   
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