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1.
Transvaginal ultrasound measurements of the fetal heart at 11 to 17 weeks of gestation. 总被引:2,自引:0,他引:2
The scope of this article is to report on transvaginal ultrasound measurements of the fetal heart, which were performed in 124 healthy fetuses at 11 to 17 weeks of gestation. Normative growth charts were constructed. Statistical analysis demonstrated linear correlation (y = a + bx) between gestational age and measurements of the right and left ventricles. The ratio between fetal heart and the transverse diameter of the chest was found to be nearly constant at these gestational ages. 相似文献
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'Doctors must not kill' 总被引:2,自引:0,他引:2
Four physicians respond to "It's over, Debbie," an anonymous resident physician's account of an incident when he or she injected a terminally ill cancer patient with a lethal dose of morphine (JAMA 1988 Jan 8; 259(2): 272). Gaylin and his colleagues condemn both the physician's violation of legal and ethical norms, and the conduct of JAMA's editor in publishing the article without editorial rebuke or comment. They warn that the issue of active euthanasia "touches medicine at its very moral center," and that, as pressure to legalize euthanasia in response to patient demand increases, the medical profession must repudiate direct and intentional killing of patients and discipline doctors who kill. 相似文献
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AIMS: Epstein-Barr virus (EBV) immortalises B cells in vitro and is associated with several malignancies. Most phenotypic effects of EBV are mediated by latent membrane protein 1 (LMP1), which interacts with tumour necrosis factor receptor associated factors (TRAFs) to activate NF-kappaB. This study examines TRAF1 and LMP1 expression in EBV associated lymphoproliferations. METHODS: TRAF1 expression was investigated in 26 Hodgkin lymphomas (HL; 18 EBV+, eight EBV-), seven EBV+ Burkitt lymphomas (BL), two infectious mononucleosis (IM) tonsils, and lymphoreticular tissue from eight chronic virus carriers. Seven anaplastic large cell lymphomas and 10 follicular B cell lymphomas were also studied. Colocalisation of TRAF1 and LMP1 was studied by immunofluorescent double labelling and confocal laser microscopy. RESULTS: TRAF1 colocalises with LMP1 in EBV infected cells in IM. EBV positive lymphocytes from chronic virus carriers were negative for TRAF1 and LMP1. In HL biopsies, TRAF1 was strongly expressed independently of EBV status, whereas all BL cases were TRAF1-. In EBV+ HL cases, TRAF1 colocalised with LMP1. Eight of 10 follicular lymphomas expressed TRAF1 in centroblast-like cells. Four of seven anaplastic large cell lymphomas weakly expressed TRAF1. CONCLUSIONS: These results suggest that in non-neoplastic lymphocytes, TRAF1 expression is dependent on the presence of LMP1, and that in IM B cells in vivo, LMP1 associated signalling pathways are active. In HL, TRAF1 is expressed independently of EBV status, probably because of constitutive NF-kappaB activation. The function of TRAF1 in HL remains to be determined. 相似文献
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Die Anaesthesiologie - 相似文献
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Abanish Singh Michael A Babyak Daniel K Nolan Beverly H Brummett Rong Jiang Ilene C Siegler William E Kraus Svati H Shah Redford B Williams Elizabeth R Hauser 《European journal of human genetics : EJHG》2015,23(6):854-862
We performed gene–environment interaction genome-wide association analysis (G × E GWAS) to identify SNPs whose effects on metabolic traits are modified by chronic psychosocial stress in the Multi-Ethnic Study of Atherosclerosis (MESA). In Whites, the G × E GWAS for hip circumference identified five SNPs within the Early B-cell Factor 1 (EBF1) gene, all of which were in strong linkage disequilibrium. The gene-by-stress interaction (SNP × STRESS) term P-values were genome-wide significant (Ps=7.14E−09 to 2.33E−08, uncorrected; Ps=1.99E−07 to 5.18E−07, corrected for genomic control). The SNP-only (without interaction) model P-values (Ps=0.011–0.022) were not significant at the conventional genome-wide significance level. Further analysis of related phenotypes identified gene-by-stress interaction effects for waist circumference, body mass index (BMI), fasting glucose, type II diabetes status, and common carotid intimal–medial thickness (CCIMT), supporting a proposed model of gene-by-stress interaction that connects cardiovascular disease (CVD) risk factor endophenotypes such as central obesity and increased blood glucose or diabetes to CVD itself. Structural equation path analysis suggested that the path from chronic psychosocial stress to CCIMT via hip circumference and fasting glucose was larger (estimate=0.26, P=0.033, 95% CI=0.02–0.49) in the EBF1 rs4704963 CT/CC genotypes group than the same path in the TT group (estimate=0.004, P=0.34, 95% CI=−0.004–0.012). We replicated the association of the EBF1 SNPs and hip circumference in the Framingham Offspring Cohort (gene-by-stress term P-values=0.007–0.012) as well as identified similar path relationships. This observed and replicated interaction between psychosocial stress and variation in the EBF1 gene may provide a biological hypothesis for the complex relationship between psychosocial stress, central obesity, diabetes, and cardiovascular disease. 相似文献
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Daniel J. Peart Richard J. Kirk Angela R. Hillman Leigh A. Madden Jason C. Siegler Rebecca V. Vince 《European journal of applied physiology》2013,113(1):127-134
The purpose of this study was to investigate the effects of pre-exercise alkalosis on the physiological stress response to high-intensity exercise. Seven physically active males (age 22 ± 3 years, height 1.82 ± 0.06 m, mass 81.3 ± 8.4 kg and peak power output 300 ± 22 W) performed a repeated sprint cycle exercise following a dose of 0.3 g kg?1 body mass of sodium bicarbonate (NaHCO3) (BICARB), or a placebo of 0.045 g kg?1 body mass of sodium chloride (PLAC). Monocyte-expressed heat shock protein 72 (HSP72) and plasma thiobarbituric acid reactive substances (TBARS) were significantly attenuated in BICARB compared to PLAC (p = 0.04 and p = 0.039, respectively), however total anti-oxidant capacity, the ratio of oxidised to total glutathione, cortisol, interleukin 6 and interleukin 8 were not significantly induced by the exercise. In conclusion, monocyte-expressed HSP72 is significantly increased following high-intensity anaerobic exercise, and its attenuation following such exercise with the ingestion of NaHCO3 is unlikely to be due to a decreased oxidative stress. 相似文献
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Doricchi F Iaria G Silvetti M Figliozzi F Siegler I 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,178(4):450-461
Despite decades of research, the question of whether the rapid eye movements (REMs) of paradoxical sleep (PS) are equivalent
to waking saccades and whether their direction is congruent with visual spatial events in the dream scene is still very controversial.
We gained an insight into these questions through the study of a right brain damaged patient suffering attentional neglect
for the left side of space and drop of the optokinetic nystagmus (OKN) with alternating rightward slow/leftward fast phases
evoked by rightward optic flow. During PS the patient had frequent Nystagmoid REMs with alternating leftward slow/rightward
fast phases and reported dreams with visual events evoking corresponding OKN such as a train running leftward. By contrast,
just as in waking OKN, Nystagmoid REMs with alternating rightward slow/leftward fast phases were virtually absent. REMs followed
by staring eye position or by consecutive REMs were also observed: these showed no asymmetry comparable to that of Nystagmoid
ones. The selective disappearance of Nystagmoid REMs in one horizontal direction proves, for the first time, that in humans
different types of REMs exists and that these are driven by different premotor mechanisms. Concomitant drop of OKN and Nystagmoid
REMs toward the same horizontal direction demonstrates that phylogenetically ancient oculomotor mechanisms, such as the OKN,
are shared by waking and PS. On this evidence and converging findings from animal, neuropsychological and brain imaging studies,
a new evolutionary account of dream bizarreness is proposed. Classification and labelling of the different types of REMs are
also provided. 相似文献