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21.
22.
Madhotra D Fenton JE Makura ZG Charters P Roland NJ 《Irish journal of medical science》2004,173(4):197-199
Background The timing of aggressive airway intervention in adult epiglottitis is controversial.
Aims To correlate Friedman’s staging of epiglottitis on admission with the airway interventions undertaken.
Methods A retrospective study of 23 adult patients, mean age 51 years (range 29–81 years), who had been admitted with acute supraglottitis
between March 1988 and December 2000 was undertaken.
Results Three patients (13%) had airway interventions; two with tracheostomy and one with tracheal intubation. All were Friedman
stage III and had rapid symptom progression during the 24 hours prior to admission. Three other stage III patients with symptom
progression longer than 24 hours and all the remaining patients (stage II or less) were managed with observation and intravenous
therapy.
Conclusions Friedman originally advocated airway intervention in any patient stage II or worse, but this intubation threshold should
probably be lowered to those patients with rapid-onset stage III (moderate respiratory distress, stridor, respiratory rate
>30 per minute, pCO2 >45mmHg) disease. 相似文献
23.
The hematopoietic stem cells of alpha-thalassemic mice 总被引:1,自引:0,他引:1
The alpha-thalassemic mouse has a hereditary microcytic anemia, almost certainly has a shortened RBC life span, and is a potential candidate for cell replacement therapy. In a routine study of bone marrow repopulating capacity using hemoglobin as a cell marker, normal donor marrow cells, but not alpha-thalassemic donor marrow cells, completely replaced the host cells. Further analysis showed that at least 30 times more alpha-thalassemic cells were required to outcompete normal donor cells injected simultaneously. The results were more extreme then expected and suggested a defect in a stem cell population as well as in the RBCs. Evidence that the multipotent and erythroid-committed stem cells in alpha-thalassemic mice are not decreased was shown by CFU-S and CFU-E assays. The combined results indicate that the deletion expresses itself most conspicuously in the RBC population. Tests were also performed to analyze repopulation kinetics in the Hbath-J/+ mice. In unirradiated alpha-thalassemic hosts, the hemoglobin from a normal donor persisted but did not replace the host hemoglobin. Sublethally irradiated alpha-thalassemic hosts, on the other hand, were easily repopulated with normal cells. We conclude that the alpha-thalassemic mouse is a good model for cell replacement therapy. 相似文献
24.
SUBIN PARK MAENG JE CHO SUNG MAN CHANG JAE NAM BAE HONG JIN JEON SEONG‐JIN CHO BYUNG‐SOO KIM IN‐WON CHUNG JOON HO AHN HAE WOO LEE JIN PYO HONG 《Journal of sleep research》2010,19(4):567-577
The aim of this study is to examine relationships of sleep duration with sociodemographic and health‐related factors, psychiatric disorders and sleep disturbances in a nationwide sample in Korea. A total of 6510 subjects aged 18–64 years participated in this study. Logistic regression was used to calculate the odd ratios and 95% confidence intervals of the covariates, psychiatric disorders and sleep disturbances across the following sleep duration categories: 5 h or less, 6, 7, 8 and 9 h or more per day. Low levels of education, unemployment and physical illness were associated with sleeping for 5 h or less and 9 h or more. Being older and widowed/divorced/separated, high levels of physical activity, pain/discomfort, obesity and high scores on the General Health Questionnaires were associated with sleeping for 5 h or less. Female, being younger and underweight were associated with sleeping for 9 h or more. Alcohol dependence, anxiety disorder and social phobia were associated significantly with sleeping for 5 h or less and 9 h or more. Other psychiatric disorders were more common in subjects who slept for 5 h or less (e.g. alcohol use disorder, mood disorder, major depressive disorder, dysthymic disorder, obsessive‐compulsive disorder and specific phobia) or 9 h or more (e.g. post‐traumatic stress disorder). In addition, subjects who slept for 5 h or less reported more sleep disturbances than did subjects who slept for 7 h. Short or long sleep is associated with psychiatric disorders and/or sleep disturbance, therefore attention to the mental health of short or long sleepers is needed. 相似文献
25.
26.
Hermine A van Duyvenvoorde Julian C Lui Sarina G Kant Wilma Oostdijk Antoinet CJ Gijsbers Mari?tte JV Hoffer Marcel Karperien Marie JE Walenkamp Cees Noordam Paul G Voorhoeve Verónica Mericq Alberto M Pereira Hedi L Claahsen-van de Grinten Sandy A van Gool Martijn H Breuning Monique Losekoot Jeffrey Baron Claudia AL Ruivenkamp Jan M Wit 《European journal of human genetics : EJHG》2014,22(5):602-609
Height is a highly heritable and classic polygenic trait. Recent genome-wide association studies (GWAS) have revealed that at least 180 genetic variants influence adult height. However, these variants explain only about 10% of the phenotypic variation in height. Genetic analysis of short individuals can lead to the discovery of novel rare gene defects with a large effect on growth. In an effort to identify novel genes associated with short stature, genome-wide analysis for copy number variants (CNVs), using single-nucleotide polymorphism arrays, in 162 patients (149 families) with short stature was performed. Segregation analysis was performed if possible, and genes in CNVs were compared with information from GWAS, gene expression in rodents'' growth plates and published information. CNVs were detected in 40 families. In six families, a known cause of short stature was found (SHOX deletion or duplication, IGF1R deletion), in two combined with a de novo potentially pathogenic CNV. Thirty-three families had one or more potentially pathogenic CNVs (n=40). In 24 of these families, segregation analysis could be performed, identifying three de novo CNVs and nine CNVs segregating with short stature. Four were located near loci associated with height in GWAS (ADAMTS17, TULP4, PRKG2/BMP3 and PAPPA). Besides six CNVs known to be causative for short stature, 40 CNVs with possible pathogenicity were identified. Segregation studies and bioinformatics analysis suggested various potential candidate genes. 相似文献
27.
CJ Stewart ECL Marrs S Magorrian A Nelson C Lanyon JD Perry ND Embleton SP Cummings JE Berrington 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(11):1121-1127
Aim: To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS). Methods: Ninety‐nine stools from 38 infants of median 27‐week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities. Results: Standard microbiological culture identified a mean of two organisms (range 0–7), DGGE 12 (range 3–18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively. Conclusions: Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration. 相似文献
28.
Telfer JF; Thomson AJ; Cameron IT; Greer IA; Norman JE 《Human reproduction (Oxford, England)》1997,12(10):2306-2312
Superoxide, an agent which attenuates the half-life of nitric oxide, is
metabolized and synthesized by superoxide dismutase (SOD) and xanthine
oxidase, respectively. Over the last few years much work has focused on the
role of nitric oxide in human parturition. The aim of this study was to
determine whether the onset of human parturition is associated with a
change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD),
manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the
uterus. Samples of myometrium, placenta, decidua and fetal membranes were
obtained from women before and after the onset of labour at term.
Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine
oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like
immunoreactivity was detected in syncytiotrophoblast cells, villous stromal
cells and endothelial cells of blood vessels in the placenta. In the
myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial
cells and to some vascular smooth muscle cells. In the fetal membranes we
observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion,
extravillous trophoblast and decidua. There was no difference in SOD enzyme
activity or staining intensity for SOD between different cell types before
and during labour. Xanthine oxidase immunoreactivity was identified in each
of the tissues examined and again there was no difference in immunostaining
in tissues obtained from women delivered before or after the onset of
labour. These results show that the pregnant uterus is capable of both
synthesizing and degrading superoxide and suggest that superoxide dismutase
and xanthine oxidase may play a role in the maintenance of uterine
quiescence during pregnancy, but not in the initiation of parturition.
相似文献
29.
Hormonal fluctuations associated with the menstrual cycle influence
appetite control and eating behaviour. Energy intake varies during the
reproductive cycle in humans and animals, with a periovulatory nadir and a
luteal phase peak. Patterns of macronutrient selection show less
consistency but a number of studies report carbohydrate cravings in the
premenstrual phase, particularly in women with premenstrual syndrome. The
cyclical nature of food cravings are frequently, but not invariably,
associated with depression. Fluctuations in appetite, cravings and energy
intake during the menstrual cycle may occur in parallel with cyclical
rhythms in serotonin, which can be accompanied by affective symptoms. The
premenstrual phase can be considered as a time when women are especially
vulnerable to overconsumption, food craving and depression; this is often
associated with low serotonin activity.
相似文献
30.
Hydrosalpinges adversely affect markers of endometrial receptivity 总被引:22,自引:10,他引:22
Meyer WR; Castelbaum AJ; Somkuti S; Sagoskin AW; Doyle M; Harris JE; Lessey BA 《Human reproduction (Oxford, England)》1997,12(7):1393-1398
While in-vitro fertilization (IVF) was initially developed in women with
tubal factor infertility, recent clinical studies have suggested that the
presence of hydrosalpinges lowers implantation and pregnancy rates. We
postulated that these hydrosalpinges cause impaired endometrial
receptivity. A total of 103 women with hydrosalpinges were prospectively
evaluated, and compared with 55 infertile and 44 fertile controls. All
women had endometrial biopsies during the window of implantation, analysed
by conventional histological criteria, and also stained for three integrin
markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha
vbeta3). Women with hydrosalpinges (cases) expressed significantly less of
the alpha vbeta3 integrin compared with controls. There was no difference
in expression of alpha1beta1 or alpha4beta1 among groups. A significantly
greater number of cases had out of phase histology and missing alpha vbeta3
(type I defects) and absent integrin expression despite normal histological
maturation (type II) defects, compared with controls. Of 20 women with
impaired endometrial receptivity who were also biopsied after hydrosalpinx
surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven
percent of type I and 57% of type II defects were corrected
postoperatively. Using markers of endometrial receptivity, this study
demonstrates that inflammatory hydrosalpinges have an adverse effect on
endometrial receptivity, which in some cases may be overcome by surgical
treatment of the hydrosalpinx.
相似文献