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51.
BACKGROUND: The aim of this study is to determine systolic and diastolic velocity profiles of the left and right ventricles by tissue Doppler imaging (TDI) and to reveal the associations between TDI parameters and early atherosclerotic changes in adult hypopituitary patients with GH deficiency. PATIENTS AND METHODS: The study group is composed of 16 hypopituitary, GH-deficient patients and 13 healthy controls. All patients had been receiving adequate substitution therapy other than GH at stable doses for at least 6 months. Conventional Doppler echocardiography and TDI of the mitral and tricuspid annulus were performed. Intima-media thickness (IMT) of the common carotid artery was calculated. RESULTS: IMT was significantly higher in the hypopituitary group compared with controls (0.83 +/- 0.25 vs. 0.51 +/- 0.14 mm, p < 0.001). Hypopituitary patients had significantly lower peak early diastolic (Em) mitral annular velocity (11.2 +/- 3.0 vs. 13.9 +/- 2.8 cm/s, p < 0.05). Multiple regression analysis revealed that age was the only independent variable significantly associated with Em and IMT in the patients. CONCLUSION: Diastolic abnormalities on TDI of the mitral annulus and early atherosclerotic changes occur concurrently in asymptomatic hypopituitary patients with GH deficiency. Aging may have a more deleterious effect on ventricular function and atherogenesis in this group of patients.  相似文献   
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The aim is to examine whether the changes in pleural fluid interleukin (IL)-1beta, IL-2, IL-6, and IL-8 levels were significant in differential diagnosis of childhood pleural effusions. IL-1beta, IL-2, IL-6, and IL-8 levels in pleural fluids of all 36 patients were measured. The levels of IL-1beta, IL-2, IL-6, and IL-8 in pleural fluids were statistically significantly higher in the transudate group compared with those of the exudate group. The levels of IL-1 beta, IL-6, and IL-8 were also found to be statistically significantly higher in the empyema group compared with both the parapneumonic and the tuberculous pleural effusion groups. The levels of IL-2 and IL-6 were detected to be statistically significantly higher in the tuberculous pleural effusion group in comparison with those of the parapneumonic effusion group. The results showed that pleural fluids IL-1beta, IL-2, IL-6, and IL-8 could be used in pleural fluids exudate and transudate distinction.  相似文献   
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The physicochemical properties of tarhana soup produced with different dough treatments, fermentation times, and preservation methods were examined. Tarhana doughs were prepared with yogurt (control) or baker's yeast (Saccharomyces cerevisiae) and fermented for 3 days. Samples were taken at 24, 48, and 72 hr. Samples were then preserved via one of four methods: sun dried, dried in the shade, vacumn dried, and frozen. Frozen samples produced lower organic acid levels after 72 hr of fermentation in both control (0.68 g/100 g) and yeast (0.61 g/100 g) applications than samples that were dried (0.94 g/100 g control samples; 0.81 g/100 g samples with yeast). Increasing fermentation time resulted in a significant effect on the formation of organic acid in the tarhana (p < .01). At 72 hr of fermentation, total acidity increased 11%, 17%, and 23% for tarhana samples vacumn-dried, sun-dried, and dried in the shade, respectively. Preservation methods also affected the moisture, ash, crude protein, total acidity, pH, salt, fat, reducing sugar levels, and the sensory assestment of tarhana soup (p < .01). Sensory characteristics were not significantly affected by baker's yeast in any of the preservation methods used (p > .01). However, sensory scores for tarhana prepared from the samples dried in a sheltered area showed a reduction in color desireablilty as the fermentation time increased. The soup prepared from frozen tarhana (72 hr fermentation, with yeast) had the highest scores with respect to color, mouth feel, flavor, and overall acceptability. Vacuum-dried samples' scores in these areas were also high in comparison to the two other drying methods.  相似文献   
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Chen Z  Kurt N  Rajagopalan S  Cavagnero S 《Biochemistry》2006,45(40):12325-12333
Little is known about polypeptide conformation and folding in the presence of molecular chaperones participating in protein biosynthesis. In vitro studies on chaperone-substrate complexes have been mostly carried out with small peptide ligands. However, the technical challenges associated with either competing aggregation or spectroscopically unfavorable size and exchange rates have typically prevented analysis of larger substrates. Here, we report the high-resolution secondary structure of relatively large N-terminal protein fragments bound to the substrate-binding domain of the cotranslationally active chaperone DnaK. The all-alpha-helical protein apomyoglobin (apoMb), bearing the ubiquitous globin fold, has been chosen as a model substrate. On the basis of NMR secondary chemical shift analysis, we identify, for the first time, weak helical content (similar to that found in the chemically unfolded full-length protein) for the assigned residues of the chaperone-bound chain away from the chaperone binding sites. In contrast, we found that the residues corresponding to the strongest specific binding site for DnaK, examined via a short 13-mer apoMb peptide fragment matching the binding site sequence, display highly reduced helical content in their chaperone-bound form. Given that the free state of the peptide is weakly helical in isolation, we conclude that the substrate residues corresponding to the chaperone binding site undergo helix unwinding upon chaperone binding.  相似文献   
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The present study was undertaken to determine the effects of intracerebroventricular (i.c.v.) and intraperitoneal (i.p.) melatonin on mechanical allodynia and thermal hyperalgesia in mice with partial tight ligation of the sciatic nerve, and how the nitric oxide (NO) precursor l-arginine and the opiate antagonist naloxone influence this effect. A plantar analgesic meter was used to assess thermal hyperalgesia, and nerve injury-induced mechanical hyperalgesia was assessed with von Frey filaments. 1-5 weeks following the surgery, marked mechanical allodynia and thermal hyperalgesia developed in neuropathic mice. Intracerebroventricular and intraperitoneal melatonin, with its higher doses, produced a blockade of thermal hyperalgesia, but not mechanical allodynia. Administration of both l-arginine and naloxone, at doses which produced no effect on their own, partially reversed antihyperalgesic effect of melatonin. These results suggest that although it has different effects on neuropathic pain-related behaviors, melatonin may have clinical utility in neuropathic pain therapy in the future. It is also concluded that l-arginine-NO pathway and opioidergic system are involved in the antihyperalgesic effect of melatonin in nerve-injured mice.  相似文献   
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microRNAs, regulators of complex phenotypes microRNAs (miRNAs) are small, non‐coding RNAs that regulate a number of biological processes, including development. Due to their mode of action some miRNAs are also causally involved in diseases like cancer. miRNAs bind base‐complementary mRNAs and lead to either degradation of the bound mRNAs or translational repression. Both result in decreased protein levels of the particular target. miRNA selectivity is governed via a very short, just six to seven nucleotides long, ”seed" sequence which is likely to exist in many mRNAs. miRNAs are, therefore, believed to target a larger number of mRNAs, each, leading to the concerted regulation of functionally connected proteins and to thus substantially contribute to phenotypes. We have performed several screenings which suggest that, indeed, many miRNAs regulate a larger number of proteins. However, we also showed that the proteins we tested were regulated by a larger number of miRNAs each. The complexity of miRNA regulation opens new avenues towards reaching a molecular understanding of disease phenotypes via the integrated consideration of coordinated regulations.  相似文献   
59.

Background  

Micro- and macroarray technologies help acquire thousands of gene expression patterns covering important biological processes during plant ontogeny. Particularly, faithful visualization methods are beneficial for revealing interesting gene expression patterns and functional relationships of coexpressed genes. Such screening helps to gain deeper insights into regulatory behavior and cellular responses, as will be discussed for expression data of developing barley endosperm tissue. For that purpose, high-throughput multidimensional scaling (HiT-MDS), a recent method for similarity-preserving data embedding, is substantially refined and used for (a) assessing the quality and reliability of centroid gene expression patterns, and for (b) derivation of functional relationships of coexpressed genes of endosperm tissue during barley grain development (0–26 days after flowering).  相似文献   
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