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1.
Interventional MRI is one of the most recent developments of clinical MR imaging. Because of the development of open MR systems and very compact high-field systems, a number of interventional procedures are already possible today under MR control and will be tested in experimental and clinical investigations. The currently commercially available systems differ with respect to their static magnetic field strength, their gradient systems and patient access. In addition, there are differences concerning their space requirements and costs. All systems have components facilitating interventional procedures. In this article we discuss the advantages and shortcomings of these commercially available systems and look at future developments in interventional MR equipment. 相似文献
2.
JM Pettifor GP Moodley FS Hough H Koch T Chen Z Lu MF Holick 《Canadian Metallurgical Quarterly》1996,86(10):1270-1272
AIMS: To assess the effect of season and latitude on the in vitro formation of previtamin D3 and vitamin D3 from 7-dehydrocholesterol (7-DHC) by sunlight in two cities in South Africa, Cape Town and Johannesburg. METHODS: An in vitro study utilising vials containing 7-DHC, which were exposed to sunlight for a period of 1 hour between 8:00 and 17:00 on 1 day a month for a year. Previtamin D3 and vitamin D3 were separated from 7-DHC by high-performance liquid chromatography, and the amounts formed were calculated with the use of external standards. RESULTS: A marked seasonal variation in vitamin D3 production was noted in Cape Town, with very little being formed during the winter months of April through September. In Johannesburg, in vitro formation changed little throughout the year, and was similar to that found in Cape Town during the summer. During sunlit hours, vitamin D3 production was maximal at midday and small quantities were still being formed between 8:00 and 9:00, and between 16:00 and 17:00 during the summer. During winter in Cape Town, peak formation at midday was less than one-third of that in Johannesburg, and negligible amounts were formed before 10:00 and after 15:00. CONCLUSIONS: The previously documented seasonal variation in serum 25-hydroxyvitamin D recorded in patients in Johannesburg is probably a consequence of the increased clothing worn and the decreased time spent out of doors during winter, rather than decreased ultraviolet radiation reaching the earth. The limited in vitro formation of vitamin D3 during winter in Cape Town may have clinical implications insofar as the management of metabolic bone diseases like rickets and osteoporosis is concerned. Breast-fed infants resident in the area are likely to suffer from vitamin D deficiency rickets unless vitamin D supplements are provided, or the mothers are encouraged to take their children out of doors. 相似文献
3.
DM Hall R Beal-Preston J Geefhuysen GP Moodley 《Canadian Metallurgical Quarterly》1976,50(20):761-763
Analysis of milk formula feeds in a community where infant malnutrition is common, showed that overdilution of feeds is less frequent than expected. Many feeds were too concentrated. Modified and 'humanised' milks were more often and more seriously too strong than unmodified milks. An inadequate number and volume of milk feeds per day was probably more important in causing malnutrition than the strength of the feeds. 相似文献
4.
OBJECTIVE: To investigate free alpha-human chorionic gonadotropin (hCG) as a marker of preeclampsia. METHODS: Four groups of patients were studied: normal pregnancies, preeclampsia, eclampsia and normal pregnant women <20 weeks' gestation. Patients were further divided according to parity and gestational age (< or =20, 21-30, 31-40 weeks). An immunoradiometric assay employing monoclonal antibodies specific for free alpha-hCG was used. RESULTS: A total of 313 patients were analyzed. Thirty-four patients < or =20 weeks' gestation were followed until delivery: five (14.7%) developed preeclampsia; none had abnormal alpha-hCG levels before onset of preeclampsia. Patients with preeclampsia (21-30 weeks' gestation) demonstrated a mean alpha-hCG level greater than that of normotensive controls but this was not statistically significant. Between 31 and 40 weeks' gestation, mean alpha-hCG levels in the hypertensive and control groups were 210.8 ng/ml and 115.8 ng/ml, respectively (P < 0.001). A stronger association was observed between alpha-hCG and preeclampsia with increasing gestational age (relative risk [RR] 2.07, 21-30 weeks; RR 3.02, 31-40 weeks) and severity (RR 4.51, mild; RR 12.15, severe; RR 16.88, eclampsia). CONCLUSION: There is a strong association between alpha-hCG and preeclampsia, nevertheless this test is unsuitable for predicting preeclampsia. 相似文献
5.
In previous studies, we reported that neonates of women with gestational diabetes mellitus (GDM) have reduced blood levels
of arachidonic acid (AA) and docosahexaenoic acid (DHA) that were unrelated to maternal status. Since both AA and DHA are
selectively transferred from maternal to fetal circulation by the placenta, we have investigated whether the FA composition
of the placenta is altered by GDM. Thirty-six women, 11 with and 25 without GDM, were recruited from Newham General Hospital,
London. The women with GDM had higher levels of di-homo-γ-linolenic (P<0.05), docosate-traenoic (n-6 DTA; P<0.0001), docosapentaenoic n-6 (P<0.005), total n-6 (P<0.005), docosapentaenoic (n-3 DPA; P<0.005), and total n-3 (P<0.01) FA, as well as higher levels of AA (P<0.05) and DHA (P<0.01), in placental choline phosphoglycerides (CPG) compared with the healthy women who served as controls. Similarly, the
women with GDM had elevated n-6 DTA (P<0.005), AA, total n-6 metabolites (P<0.05), DHA, total n-3 metabolites, and total n-3 FA (P<0.005) in ethanolamine phosphoglycerides (EPG). In contrast to CPG and EPG, the placental TG of the women with GDM had higher
linoleic acid (P<0.05) and lower AA, n-6 metabolites, and n-3 DPA (P<0.01). The placenta is devoid of desaturase activity, and it is thought to be reliant on maternal circulation for both AA
and DHA. Hence, the enhanced levels of the two FA in the placenta of the GDM group suggests that these FA are taken up from
the maternal circulation and retained after esterification into phosphoglycerides instead of being transferred to the fetus.
Further study is needed to elucidate the mechanism involved and the effect of the phenomenon on postnatal growth and development
of the offspring. 相似文献
6.
Shabarinath Nambiar Dino Bee Aik Tan Britt Clynick Sze How Bong Catherine Rawlinson Joel Gummer Tamera J. Corte Ian Glaspole Yuben P. Moodley Robert Trengove 《Proteomics. Clinical applications》2021,15(2-3):2000039
Chronic obstructive pulmonary disease (COPD) is characterised by airway inflammation and progressive airflow limitation, whereas idiopathic pulmonary fibrosis (IPF) is characterised by a restrictive pattern due to fibrosis and impaired gas exchange. We undertook metabolomic analysis of blood samples in IPF, COPD and healthy controls (HC) to determine differences in circulating molecules and identify novel pathogenic pathways. An untargeted metabolomics using an ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometer (UHPLC-QTOF-MS) was performed to profile plasma of patients with COPD (n = 21), and IPF (n = 24) in comparison to plasma from healthy controls (HC; n = 20). The most significant features were identified using multiple database matching. One-way ANOVA and variable importance in projection (VIP) scores were also used to highlight metabolites that influence the specific disease groups. Non-polar metabolites such as fatty acids (FA) and membrane lipids were well resolved and a total of 4805 features were identified. The most prominent metabolite composition differences in lipid mediators identified at ∼2–3 fold higher in both diseases compared to HC were palmitoleic acid, oleic acid and linoleic acid; and dihydrotestosterone was lower in both diseases. We demonstrated that COPD and IPF were characterised by systemic changes in lipid constituents such as essential FA sampled from circulating plasma. 相似文献
7.
Sagren Moodley 《Information Technology for Development》2013,19(1):25-40
Business-to-business electronic commerce has become a priority area for many international development organisations, particularly since concerns about the ‘digital divide’ have put the policymaking spotlight on the connection between ICTs and industrial development policies. This paper aims to explore the current state and likely future direction of B2B e-commerce in the South African manufacturing sector. The empirical research is based on 120 firm-level interviews, and 31 personal interviews with industry experts. The results suggest that B2B e-commerce is in an embryonic stage in the South African manufacturing sector, and technology and market dynamics are still casting its basic shape. The ability to realise efficiency gains in the B2B electronic marketplace will largely hinge on the climate of confidence and trust that businesses are able to create in their relations with their suppliers and customers. We argue that policy decisions will have a major impact on the kind of environment in which e-commerce will develop and should therefore be crafted with due recognition of its fragile and evolving nature. 相似文献
8.
Crawford MA Golfetto I Ghebremeskel K Min Y Moodley T Poston L Phylactos A Cunnane S Schmidt W 《Lipids》2003,38(4):303-315
The risk of central nervous, visual, and auditory damage increases from 2/1000 live births in the normal birthweight to >200/1000
as birthweight falls below 1500 g. Such babies are most likely to be born preterm. Advances in infant care have led to increasing
numbers of very-low-birthweight, preterm infants surviving to school age with moderate to severe brain damage. Steroids are
one of the current treatments, but they cause significant, long-term problems. The evidence reported here suggests an additional
approach to protecting the very preterm infant by supporting neurovascular membrane integrity. The complications of preterm,
very-low-birthweight babies include bronchopulmonary dysplasia, retinopathy of prematurity, intraventricular hemorrhage, periventricular
leukomalacia, and necrotizing enterocolitis, all of which have a vascular component. Arachidonic acid (AA) and DHA are essential,
structural, and functional constituents of cell membranes. They are especially required for the growth and function of the
brain and vascular systems, which are the primary biofocus of human fetal growth. Molecular dynamics and experimental evidence
suggest that DHA could be the ligand for the retinoid X receptor (RXR) in neural tissue. RXR activation is an obligatory step
in signaling to the nucleus and in the regulation of gene expression. Very preterm babies are born with minimal fat stores
and suboptimal circulating levels of these nutrients. Postanatally, they lose the biomagnification of the proportions of AA
and DHA by the placenta for the fetus. No current nutritional management repairs these deficits. The placental biomagnification
profile highlights AA rather than DHA. The resultant fetal FA profile closely resembles that of the vascular endothelium and
not the brain. Without this nourishment, cell membrane abnormalities would be predicted. We present a scientific rationale
for a common pathogenic process in the complications of prematurity. 相似文献
9.
Thoracobiliary fistula is a rare complication of hepatic trauma that may present a diagnostic and therapeutic challenge. We report a case of a thoracobiliary fistula complicating thoracoabdominal trauma. Although numerous imaging modalities are able to detect the condition, optimal imaging is achieved with endoscopic retrograde cholangiography, which provides anatomic delineation and has the therapeutic potential of a sphincterotomy. Conservative therapy consists of a safe temporizing measure during the workup and may, on occasion, be the only therapy that is necessary provided that controlled drainage of the fistula is achieved. The current recommendation would be the exhaustion of nonoperative therapeutic modalities before resorting to surgical intervention. 相似文献
10.
Does HIV status influence the outcome of patients admitted to a surgical intensive care unit? A prospective double blind study 总被引:1,自引:0,他引:1
S Bhagwanjee DJ Muckart PM Jeena P Moodley 《Canadian Metallurgical Quarterly》1997,314(7087):1077-81; discussion 1081-4
OBJECTIVES: (a) To assess the impact of HIV status (HIV negative, HIV positive, AIDS) on the outcome of patients admitted to intensive care units for diseases unrelated to HIV; (b) to decide whether a positive test result for HIV should be a criterion for excluding patients from intensive care for diseases unrelated to HIV. DESIGN: A prospective double blind study of all admissions over six months. HIV status was determined in all patients by enzyme linked immunosorbent assay (ELISA), immunofluorescence assay, western blotting, and flow cytometry. The ethics committee considered the clinical implications of the study important enough to waive patients' right to informed consent. Staff and patients were blinded to HIV results. On discharge patients could be advised of their HIV status if they wished. SETTING: A 16 bed surgical intensive care unit. SUBJECTS: All 267 men and 135 women admitted to the unit during the study period. INTERVENTIONS: None. MAIN OUTCOME MEASURES: APACHE II score (acute physiological, age, and chronic health evaluation), organ failure, septic shock, durations of intensive care unit and hospital stay, and intensive care unit and hospital mortality. RESULTS: No patient had AIDS. 52 patients were tested positive for HIV and 350 patients were tested negative. The two groups were similar in sex distribution but differed significantly in age, incidence of organ failure (37 (71%) v 171 (49%) patients), and incidence of septic shock (20 (38%) v 54 (15%)). After adjustment for age there were no differences in intensive care unit or hospital mortality or in the durations of stay in the intensive care unit or hospital. CONCLUSIONS: Morbidity was higher in HIV positive patients but there was no difference in mortality. In this patient population a positive HIV test result should not be a criterion for excluding a patient from intensive care. 相似文献