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ObjectivePatient-centered studies have shown that several patients on thyroid hormone replacement therapy for hypothyroidism exhibit persistent symptoms, including “brain fog.” Here, we aimed to determine which of these specific symptoms are associated with brain fog, identify patient-reported factors that modify these symptoms, and identify patient concerns related to brain fog not included in thyroid-specific questionnaires.MethodsA survey on brain fog symptoms adapted from thyroid-specific patient-reported outcome was distributed online. Textual data analysis was performed to identify common areas of concern from open-ended survey responses.ResultsA total of 5170 participants reporting brain fog while being treated for hypothyroidism were included in the analysis. Of these, 2409 (46.6%) participants reported symptom onset prior to the diagnosis of hypothyroidism, and 4096 (79.2%) participants experienced brain fog symptoms frequently. Of the symptoms listed, participants associated fatigue and forgetfulness most frequently with brain fog. More rest was the most common factor provided for improving symptoms. The textual data analysis identified areas of concern that are not often included in thyroid-specific quality of life questionnaires, including a focus on the diagnosis of hypothyroidism, the types and doses of medications, and the patient-doctor relationship.ConclusionBrain fog in patients treated for hypothyroidism was associated most frequently with fatigue and cognitive symptoms. Several additional areas of patient concern were found to be associated with brain fog, which are not typically addressed in thyroid-specific questionnaires.  相似文献   
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The persistence of chromosomal lesions induced in vivo by mitomycin C (MMC) was evaluated by cytogenetic analysis of mouse bone marrow cells. Chromosome aberration (CA) and micronucleus (MN) frequencies were estimated at different times after treatment, up to 42 days. The frequency of CA per cell decreased in the first 3 days after treatment, but a secondary peak appeared on the 4th day, followed by a stabilization around 0.03 CA per cell (significantly different from the control value), which persisted up to 17 days. At the next time intervals tested (28 and 42 days), the CA frequency returned to the control level. In disagreement with these data obtained directly on metaphases, the MN frequency, as evaluated in polychromatic erythrocytes, decreased quickly after treatment, reaching the control value on the 5th day. We attempted to enhance the sensitivity of the MN test by using CREST antibodies and indirect immunofluorescence. However, higher proportions of CREST- MN in treated than in control animals were observed only at short time intervals, confirming the results obtained with the conventional MN assay.  相似文献   
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Redox properties of cytochrome c553(550) from Desulfovibrio desulfuricans Norway (Eo' = 0.04 + 0.02 V/NHE) and cytochrome c551 from P. aeruginosa (Eo = 0.25 +/- 0.02 V/NHE) are compared with those of some monohemic c-type cytochromes. The pK value for the equilibrium between the pH-dependent forms of cytochrome c553(550) (pK = 10.3 +/- 0.1) has been also determined. It is to be noted that the difference between redox potentials can extend to nearly 250 mV, though the axial heme ligands are identical. Structural reasons have to be invoked to explain these variations.  相似文献   
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Seeds of dormant Douglas-fir seeds germinated poorly when they were cultivated at 20–23 °C while isolated embryos germinated fully within two weeks. Seed dormancy was therefore imposed on the embryo by its surrounding structures. This physiological behaviour was well correlated with changes in ABA level during culture. Indeed, the ABA level decreased in isolated embryos while it increased in both embryo and megagametophyte during culture of whole seeds. The origin of this increase was analysed and the different ways by which seed coats could interfere with ABA accumulation are discussed.  相似文献   
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The addition of chitosan to whole milk results in dose dependent destabilization and coagulation of the casein micelles and milk fat. The present study evaluates how the presence of chitosan could affect the hydrolysis of this chitosan-induced aggregate by different gastrointestinal proteases (pepsin and trypsin) and by pancreatic lipase. The chitosan-milk aggregate was hydrolyzed by pepsin and trypsin, as evaluated by the UV absorbance of TCA-soluble peptides and by urea-PAGE. The kinetics and extent of hydrolysis were independent of the casein being soluble or aggregated. The release of soluble peptides from the aggregate was independent of the presence of chitosan. A progressive inhibition of pancreatic lipase was observed in proportion to the increase in molecular weight of the chitosan employed to induce the formation of the aggregate. Interestingly, the presence of chitosan not only affected the initial velocity of the reaction, but also reduced its extent. The results indicate that a milk aggregate induced by chitosan was very well digested by gastric and intestinal proteases independently of the molecular weight of the chitosan used, and that the aggregate could retain the lipid-lowering effect of chitosan.  相似文献   
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