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11.
Inflammatory bowel diseases (IBD) are emerging globally, indicating that environmental factors may be important in their pathogenesis. Colonic mucosal epigenetic changes, such as DNA methylation, can occur in response to the environment and have been implicated in IBD pathology. However, mucosal DNA methylation has not been examined in treatment-naïve patients. We studied DNA methylation in untreated, left sided colonic biopsy specimens using the Infinium HumanMethylation450 BeadChip array. We analyzed 22 control (C) patients, 15 untreated Crohn’s disease (CD) patients, and 9 untreated ulcerative colitis (UC) patients from two cohorts. Samples obtained at the time of clinical remission from two of the treatment-naïve UC patients were also included into the analysis. UC-specific gene expression was interrogated in a subset of adjacent samples (5 C and 5 UC) using the Affymetrix GeneChip PrimeView Human Gene Expression Arrays. Only treatment-naïve UC separated from control. One-hundred-and-twenty genes with significant expression change in UC (> 2-fold, P < 0.05) were associated with differentially methylated regions (DMRs). Epigenetically associated gene expression changes (including gene expression changes in the IFITM1, ITGB2, S100A9, SLPI, SAA1, and STAT3 genes) were linked to colonic mucosal immune and defense responses. These findings underscore the relationship between epigenetic changes and inflammation in pediatric treatment-naïve UC and may have potential etiologic, diagnostic, and therapeutic relevance for IBD.  相似文献   
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The contents of eight trace elements (Ti, Mn, Ni, Cu, Zn, Sr, Ba, and Pb) in muscles of syntopic sexual and clonal spined loaches (the golden loach Sabanejewia baltica, diploid males and females of Cobitis taenia, and congeneric triploid clonal females) from the upper Dnieper River and in the syntopic spined loaches (males and females of C. melanoleuca and males of C. taenia) from the upper Volga River basin were determined using the X-ray fluorescence spectroscopy technique. The contents of Cu in the clonal triploid Cobitis females and diploid C. taenia females from the Dnieper are different. The intersexual differences in the contents of Pb and Zn between C. taenia males and females, as well as the interspecific differences in the content of Ti between the spined loaches from the Dnieper and Volga basins were revealed. The concentrations of Cu and Pb correlated with the individual fish size. The potential for the use of the revealed differences in the trace element contents as an indicator of the divergence of ecological niches in the syntopic spined loaches is discussed.  相似文献   
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Hypervariable "minisatellite" regions detected in human genome by wild-type M13 DNA were found to have high polymorphism and somatic stability. Analysis of individual specific patterns of 34 human DNAs from Krasnodar population is presented. The observed length of fragments ranged from 2 to 6 kb. The mean frequency of a fragment in the population under study is p = 0.247 +/- 0.171, the mean number of fragments per individual being x = 9.35 +/- 1.95. The mean probability of individual identification is calculated to be 1-2.10(-6) = 0.999998.  相似文献   
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The function of Semliki Forest Virus nsP2 protease was investigated by site-directed mutagenesis. Mutations were introduced in its protease domain, Pro39, and the mutated proteins were expressed in Escherichia coli, purified and their activity in vitro was compared to that of the wild type Pro39. Mutations M781T, A662T and G577R, found in temperature-sensitive virus strains, rendered the enzyme temperature-sensitive in vitro as well. Five conserved residues were required for the proteolytic activity of Pro39. Changes affecting Cys478, His548, and Trp549 resulted in complete inactivation of the enzyme, whereas the replacements N600D and N605D significantly impaired its activity. The importance of Trp549 for the proteolytic cleavage specificity is discussed and a new structural motif involved in substrate recognition by cysteine proteases is proposed.  相似文献   
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Following the publication of the last of the series of Flora Europaea Notulae, No. 20 in the Botanical Journal of the Linnean Society , 76: 297–384 (1978), a number of additions or alterations have been drawn to our attention. These are published in continuation.  相似文献   
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Journal of Ichthyology - We studied the mitotic chromosome sets in three elephantfish species of the genus Mormyrus (Mormyridae, Osteoglossiformes) occurring in the White Nile and Omo-Turkana...  相似文献   
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Background

Abnormal blood glucose (BG) concentrations have been associated with increased morbidity and mortality in both critically ill adults and infants. Furthermore, hypoglycaemia and glycaemic variability have both been independently linked to mortality in these patients. Continuous Glucose Monitoring (CGM) devices have the potential to improve detection and diagnosis of these glycaemic abnormalities. However, sensor noise is a trade-off of the high measurement rate and must be managed effectively if CGMs are going to be used to monitor, diagnose and potentially help treat glycaemic abnormalities.

Aim

To develop a tool that will aid clinicians in identifying unusual CGM behaviour and highlight CGM data that potentially need to be interpreted with care.

Methods

CGM data and BG measurements from 50 infants at risk of hypoglycaemia were used. Unusual CGM measurements were classified using a stochastic model based on the kernel density method and historical CGM measurements from the cohort. CGM traces were colour coded with very unusual measurements coloured red, highlighting areas to be interpreted with care. A 5-fold validation of the model was Monte Carlo simulated 25 times to ensure an adequate model fit.

Results

The stochastic model was generated using ~67,000 CGM measurements, spread across the glycaemic range ~2-10?mmol/L. A 5-fold validation showed a good model fit: the model 80% confidence interval (CI) captured 83% of clinical CGM data, the model 90% CI captured 91% of clinical CGM data, and the model 99% CI captured 99% of clinical CGM data. Three patient examples show the stochastic classification method in use with 1) A stable, low variability patient which shows no unusual CGM measurements, 2) A patient with a very sudden, short hypoglycaemic event (classified as unusual), and, 3) A patient with very high, potentially un-physiological, glycaemic variability after day 3 of monitoring (classified as very unusual).

Conclusions

This study has produced a stochastic model and classification method capable of highlighting unusual CGM behaviour. This method has the potential to classify important glycaemic events (e.g. hypoglycaemia) as true clinical events or sensor noise, and to help identify possible sensor degradation. Colour coded CGM traces convey the information quickly and efficiently, while remaining computationally light enough to be used retrospectively or in real-time.  相似文献   
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