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21.
PAX6 in sensory development   总被引:8,自引:0,他引:8  
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Spontaneous thioguanine-resistant mutants were derived from populations of finite-life-span, diploid human fibroblasts by means of a fluctuation analysis. cDNA was prepared from mutantHPRT mRNA and amplified by the polymerase chain reaction, and the sequence of the product was analyzed. Exon deletions, which very likely arose from mutations in the intron splice site consensus sequences, were found in 10 of the 37 mutants examined (27% of the total). Among the 28 mutations in the coding sequence, base pair substitutions predominated (89%). With the exception of one base pair involved in a tandem mutation, all base pair substitutions resulted in alterations in the predicted amino acid sequence of the protein. In addition there were three frameshift mutations, consisting of the deletion of one or two base pairs. Although mutations occurred throughout the coding sequence, 50% (14/28) were found in the 5 portion of exon 3.  相似文献   
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An international project (EURONIC) was carried out to explore the end-of-life decision-making process in a large, representative sample of neonatal intensive care units (NICUs) in eight western European countries: France, Germany, Great Britain, Italy, Luxembourg, the Netherlands, Spain and Sweden. Structured questionnaires were used to record data on NICU organization and policies, and to survey staff views and practices regarding ethical decision-making. One hundred and twenty-two NICUs were recruited by census or random sampling (response rate 86%); 1235 physicians and 3115 nurses completed the staff questionnaire (response rates 89 and 85%, respectively). This paper focuses on the physicians' answers. In all countries but Italy, most physicians reported having been involved at least once in setting limits to intensive care because of a baby's incurable condition and/or poor neurological prognosis. Adopted strategies varied between countries. Practices such as the continuation of current treatment without intensifying it and the withholding of emergency manoeuvres appeared widespread. In contrast, the frequency of doctors reporting withdrawal of mechanical ventilation was highest in the Netherlands (93%), Sweden (91%) and the Great Britain (88%), intermediate in France and Germany, and lowest in Spain and Italy (34 and 21%, respectively).
Conclusion: Ethically problematic clinical cases are approached differently in the various countries. The findings of this study may provide an opportunity for physicians to review their practices critically, in light of how other colleagues proceed, and foster an open discussion about these difficult issues.  相似文献   
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AIM: To determine whether fetal intrauterine resuscitation using tocolysis and delayed delivery is better for the fetus than emergency delivery when fetal hypoxia is suspected because of a non-reassuring fetal heart-rate (FHR) pattern using conventional heart rate monitoring. METHODS: This was a prospective and randomized study, conducted between 2001 and 2004 at Pereira Rossell Hospital, Montevideo, Uruguay. The population consisted of 390 fetuses, in which intrauterine distress was diagnosed using electronic FHR monitoring. Of these, 197 were randomly assigned to the emergency delivery group and 193 to the fetal intrauterine resuscitation group. The inclusion criteria were: term singleton pregnancy, in labor, cephalic presentation, and no placental accidents. RESULTS: The time between randomization and birth was 16.9 +/- 7.6 min (mean +/- SD) for the emergency delivery group, and 34.5 +/- 11.7 min (mean +/- SD) for the resuscitation group. The relative risk (RR) of acidosis in the umbilical artery (pH < 7.1) in the emergency delivery group was 1.47 (0.95-2.27). The RR of base deficit < or =12 mEq/L in the emergency delivery group was higher than in the resuscitation group (RR = 1.48 [1.0-2.2], P = 0.04). When considering the need for admission to the neonatal care unit, the relative risk was higher in the emergency delivery group than in the resuscitation group (RR = 2.14 [1.23.3.74], P = 0.005). No maternal adverse effects were reported. CONCLUSION: Tocolysis and delayed delivery renders better immediate neonatal results than emergency delivery when fetal distress is suspected because of a non-reassuring fetal heart pattern. In addition, it may decrease the need for emergency delivery without increasing maternal and fetal adverse side-effects.  相似文献   
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In order to improve fit and comfort, a maxillary protraction facemask customized to the patient’s anatomy was produced by means of 3D face scanning, digital design and additive manufacturing. An 8-year-old patient in need of early treatment for the Class III malocclusion received a rapid palatal expander and a Petit-type facemask, whose components were digitally designed on a 3D scan of the patient’s face. For face scanning, the iPad Pro 2018 tablet (Apple, Cupertino, CA, USA) with the Bellus3D DentalPro application (Bellus3D, Campbell, CA, USA) was used. Facemask components were modelled with 3D Blender software. The rests were 3D printed in BioMed Clear biocompatible resin (Formlabs, Somerville, MA, USA), and the bar in stainless steel. For greater comfort, the internal surface of the rests was lined with a polymer gel pad (Silipos, Niagara Falls, NY, USA). The manufacturing procedure of the customized facemask is patented. The patient wore the facemask at night for a period of 9 months. The patient’s experience was evaluated with a questionnaire at 1 week, 3, 6, and 10 months of treatment. The customized facemask was well accepted by the patient and obtained the expected treatment outcome. Furthermore, 3D face scanning, 3D modelling and 3D printing allow for the manufacturing of customized facemasks with improved fit and comfort, favoring patient compliance and treatment success.  相似文献   
28.
This study was aimed at characterizing the gut microbiota (GM) and its functional profile in two groups of Sardinian subjects with a long healthy life expectancy, overall named Long-Lived Subjects (LLS) [17 centenarians (CENT) and 29 nonagenarians (NON)] by comparing them to 46 healthy younger controls (CTLs). In addition, the contribution of genetics and environmental factors to the GM phenotype was assessed by comparing a subgroup of seven centenarian parents (CPAR) with a paired cohort of centenarians’ offspring (COFF). The analysis was performed through Next Generation Sequencing (NGS) of the V3 and V4 hypervariable region of the 16S rRNA gene on the MiSeq Illumina platform. The Verrucomicrobia phylum was identified as the main biomarker in CENT, together with its members Verrucomicrobiaceae, Akkermansia and Akkermansia muciniphila. In NON, the strongest associations concern Actinobacteria phylum, Bifidobacteriaceae and Bifidobacterium, while in CTLs were related to the Bacteroidetes phylum, Bacteroidaceae, Bacteroides and Bacteroides spp. Intestinal microbiota of CPAR and COFF did not differ significantly from each other. Significant correlations between bacterial taxa and clinical and lifestyle data, especially with Mediterranean diet adherence, were observed. We observed a harmonically balanced intestinal community structure in which the increase in taxa associated with intestinal health would limit and counteract the action of potentially pathogenic bacterial species in centenarians. The GM of long-lived individuals showed an intrinsic ability to adapt to changing environmental conditions, as confirmed by functional analysis. The GM analysis of centenarians’ offspring suggest that genetics and environmental factors act synergistically as a multifactorial cause in the modulation of GM towards a phenotype similar to that of centenarians, although these findings need to be confirmed by larger study cohorts and by prospective studies.  相似文献   
29.
Postpartum depression (PPD) is the most common psychological health issue among women, which often comorbids with anxiety (PPD-A). PPD and PPD-A showed highly overlapping clinical symptoms. Identifying disorder-specific neurophysiological markers of PDD and PPD-A is important for better clinical diagnosis and treatments. Here, we performed functional connectivity density (FCD) and resting-state functional connectivity (rsFC) analyses in 138 participants (45 unmedicated patients with first-episode PPD, 31 PDD-A patients and 62 healthy postnatal women, respectively). FCD mapping revealed specifically weaker long-range FCD in right lingual gyrus (LG.R) for PPD patients and significantly stronger long-range FCD in left ventral striatum (VS.L) for PPD-A patients. The follow-up rsFC analyses further revealed reduced functional connectivity between dorsomedial prefrontal cortex (dmPFC) and VS.L in both PPD and PPD-A. PPD showed specific changes of rsFC between LG.R and dmPFC, right angular gyrus and left precentral gyrus, while PPD-A represented specifically abnormal rsFC between VS.L and left ventrolateral prefrontal cortex. Moreover, the altered FCD and rsFC were closely associated with depression and anxiety symptoms load. Taken together, our study is the first to identify common and disorder-specific neural circuit disruptions in PPD and PPD-A, which may facilitate more effective diagnosis and treatments.  相似文献   
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