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101.
Flik K Kloen P Toro JB Urmey W Nijhuis JG Helfet DL 《The Journal of the American Academy of Orthopaedic Surgeons》2006,14(3):175-182
Trauma affects up to 8% of pregnancies and is the leading cause of death among pregnant women in the United States. A pregnancy test is mandated for all females of childbearing age who are involved in trauma. Orthopaedic trauma in the pregnant patient is managed similarly to that for all trauma patients. Initial resuscitation efforts should focus on the pregnant patient because stable patient vital signs provide the best chance for fetal survival. In the stable patient, fetal assessment and a pelvic examination are mandatory. Radiographs as well as abdominal ultrasound of the patient and fetal ultrasound are useful. No known biologic risks are associated with magnetic resonance imaging, and no specific fetal abnormalities have been linked with standard low-intensity magnetic resonance imaging. Emergency surgery can be safely performed in most pregnant patients. Avoiding patient hypotension and using left lateral decubitus positioning increase the likelihood of success for the patient and fetus. An experienced multidisciplinary team consisting of an obstetrician, perinatologist, orthopaedic surgeon, anesthesiologist, radiologist, and nursing staff will optimize the treatment of both the pregnant patient and her fetus. 相似文献
102.
The aim of this study was to search for the existence of behavioural states in the human fetus and to describe their developmental course. In a longitudinal study, 14 low-risk fetuses were studied at 2-week intervals from 32 weeks of gestation onward. Fetal body movements as well as fetal eye movements, visualized by means of real-time ultrasonic imaging, and fetal heart rate patterns, recorded by means of a cardiotocograph, were used as state variables.At 38 and 40 weeks, four distinct behavioural states, named states 1F through 4F and corresponding respectively to states 1 through 4 of the neonate, could be identified. That these constellations of parameters represented true behavioural states was demonstrated by the stability of association of parameters for prolonged periods and by the simultaneity of change of parameters at state transitions. There is evidence for episodes of wakefulness in the fetus. Before 36 weeks, cycles were present in each of the state variables, and combinations of parameters typical of particular states were observed. However, the relatively short durations of these combinations and the lack of simultaneity of change in the three state variables support the conclusion that these periods of coincidence occurred by chance and did not represent organized behavioural states. 相似文献
103.
Crystalline retinopathy 总被引:4,自引:0,他引:4
A 34-year-old woman had crystalline dystrophy of the retina associated with atrophy of the choriocapillaris and pigment epithelium, and pigment clumping in the fundus periphery. Consanguinity of her parents suggested an autosomal recessive inheritance pattern for this type of crystalline retinal dystrophy. The patient did not have corneal crystals. Her electroretinogram was normal, although her electro-oculogram was abnormal. 相似文献
104.
E-K Park EJ Lee S-H Lee KH Koo JY Sung EH Hwang JH Park C-W Kim K-C Jeong B-K Park Y-N Kim 《British journal of pharmacology》2010,160(5):1212-1223
Background and purpose:
Lipid rafts and caveolae are membrane microdomains with important roles in cell survival signalling involving the Akt pathway. Cholesterol is important for the structure and function of these microdomains. The ginsenoside Rh2 exhibits anti-tumour activity. Because Rh2 is structurally similar to cholesterol, we investigated the possibility that Rh2 exerted its anti-tumour effect by modulating rafts and caveolae.Experimental approach:
A431 cells (human epidermoid carcinoma cell line) were treated with Rh2 and the effects on cell apoptosis, raft localization and Akt activation measured. We also examined the effects of over-expression of Akt and active-Akt on Rh2-induced cell death.Key results:
Rh2 induced apoptosis concentration- and time-dependently. Rh2 reduced the levels of rafts and caveolae in the plasma membrane and increased their internalization. Furthermore, Akt activity was decreased and consequently, Akt-dependent phosphorylation of Bad, a pro-survival protein, was decreased whereas the pro-apoptotic proteins, Bim and Bax, were increased upon Rh2 treatment. Unlike microdomain internalization induce by cholesterol depletion, Rh2-mediated internalization of rafts and caveolae was not reversed by cholesterol addition. Also, cholesterol addition did not restore Akt activation or rescue cells from Rh2-induced cell death. Rh2-induced cell death was attenuated in MDA-MB-231 cells over-expressing either wild-type or dominant-active Akt.Conclusions and implications:
Rh2 induced internalization of rafts and caveolae, leading to Akt inactivation, and ultimately apoptosis. Because elevated levels of membrane rafts and caveolae, and Akt activation have been correlated with cancer development, internalization of these microdomains by Rh2 could potentially be used as an anti-cancer therapy. 相似文献105.
106.
Jansen M van Alfen N Nijhuis van der Sanden MW van Dijk JP Pillen S de Groot IJ 《Neuromuscular disorders : NMD》2012,22(4):306-317
Responsive outcome measures are needed to follow the disease status of Duchenne muscular dystrophy (DMD) patients, as new therapeutic approaches become available for affected boys. Quantitative muscle ultrasound (QMUS) is potentially an attractive follow up tool for DMD because it reflects the severity of the dystrophic process without the need for invasive procedures, by quantifying echo intensity (i.e., mean grey level of muscle images) and muscle thickness. We performed a longitudinal follow-up of lower and upper extremity QMUS in 18 DMD patients and compared this with physical functioning in 11 of these patients. QMUS could be performed in every patient, and no patient was subjected to more than a total of 20min of ultrasound scanning time for this study. As expected we found a significant increase of echo intensity with age, reflecting increasing dystrophic muscle changes. This increase was related to ambulatory status, functional grading, muscle strength and motor ability. Our study establishes QMUS as a practical and child-friendly tool for the longitudinal follow up of DMD patients. 相似文献
107.
Nynke Spinder Jorieke EH Bergman Hans Kromhout Roel Vermeulen Nicole Corsten-Janssen H Marike Boezen Gideon J du Marchie Sarvaas Hermien EK de Walle 《Scandinavian journal of work, environment & health》2020,46(6):599
Objectives:Congenital heart defects (CHD) are the most prevalent congenital anomalies. This study aims to examine the association between maternal occupational exposures to organic and mineral dust, solvents, pesticides, and metal dust and fumes and CHD in the offspring, assessing several subgroups of CHD.Methods:For this case–control study, we examined 1174 cases with CHD from EUROCAT Northern Netherlands and 5602 controls without congenital anomalies from the Lifelines cohort study. Information on maternal jobs held early in pregnancy was collected via self-administered questionnaires, and job titles were linked to occupational exposures using a job exposure matrix.Results:An association was found between organic dust exposure and coarctation of aorta [adjusted odds ratio (ORadj) 1.90, 95% confidence interval (CI) 1.01–3.59] and pulmonary (valve) stenosis in combination with ventricular septal defect (ORadj 2.68, 95% CI 1.07–6.73). Mineral dust exposure was associated with increased risk of coarctation of aorta (ORadj 2.94, 95% CI 1.21–7.13) and pulmonary valve stenosis (ORadj 1.99, 95% CI 1.10–3.62). Exposure to metal dust and fumes was infrequent but was associated with CHD in general (ORadj 2.40, 95% CI 1.09–5.30). Exposure to both mineral dust and metal dust and fumes was associated with septal defects (ORadj 3.23, 95% CI 1.14–9.11). Any maternal occupational exposure was associated with a lower risk of aortic stenosis (ORadj 0.32, 95% CI 0.11–0.94).Conclusions:Women should take preventive measures or avoid exposure to mineral and organic dust as well as metal dust and fumes early in pregnancy as this could possibly affect foetal heart development. 相似文献
108.
B C Hamel R Happle P M Steylen L A Kollée J H Stekhoven J G Nijhuis R Rauskolb I Anton-Lamprecht 《American journal of medical genetics》1992,44(6):824-826
Restrictive dermopathy is a rare autosomal recessive lethal skin dysplasia. It has been assumed that the characteristic morphologic abnormalities should allow a reliable prenatal diagnosis on fetal skin biopsies at about 20 weeks pregnancy. We report on a false-negative prenatal diagnosis. 相似文献
109.
J.E. Visser L.B. Oude Nijhuis L. Janssen C.M. Bastiaanse G.F. Borm J. Duysens B.R. Bloem 《Neuroscience》2010
Previous dynamic posturography studies demonstrated clear abnormalities in balance responses in Parkinson's disease (PD) patients compared to controls at the group level, but its clinical value in the diagnostic process and fall risk estimation in individual patients leaves for improvement. Therefore, we investigated whether a new approach, focusing on the balance responses to the very first and fully unpractised trial rather than a pooled mean response to a series of balance perturbations, could further improve the diagnostic utility of dynamic posturography. Following the first trial, subjects were exposed to repeated balance perturbations, which also permitted us to investigate the training responses. Fourteen patients with PD and 18 age-matched controls were enrolled, who received a series of multidirectional postural perturbations, induced by support surface rotations. We measured trunk and upper arm kinematics and electromyographic responses, and evaluated group differences at three levels: the postural response to the very first backward perturbation; pooled first and habituated postural responses; and habituation rates. Analysis of the first trial responses yielded similar results as evaluation of the mean response over trials: forward flexion of the trunk induced by backward perturbations was decreased in patients, accompanied by increased muscle responses present. Moreover, trunk movement and muscle activity were equally present in both groups—suggesting a preserved training response in PD patients. Early masseter activity in both groups might be indicative of a startle-like component to the balance response. In terms of diagnostic utility, focusing on the first trial response or habituation rate is no better than analysis of pooled responses to a series of perturbations. The apparently preserved training response in PD patients suggests that balance reactions in PD can be improved by repeated exposure, and this may have implications for future exercise studies. Early masseter activity warrants further studies to evaluate a potential startle component in the pathophysiology of balance disorders. 相似文献
110.