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排序方式: 共有786条查询结果,搜索用时 46 毫秒
741.
742.
Helen Carnaghan Catherine P. James Paul B. Charlesworth Marco Ghionzoli Susana Pereira Mohamed Elkhouli David Baud Paolo De Coppi Greg Ryan Prakesh S. Shah Mark Davenport Anna L. David Agostino Pierro Simon Eaton Gastroschisis Study Group 《黑龙江环境通报》2020,40(8):991-997
Objective
In gastroschisis, there is evidence to suggest that gut dysfunction develops secondary to bowel inflammation; we aimed to evaluate the effect of maternal antenatal corticosteroids administered for obstetric reasons on time to full enteral feeds in a multicenter cohort study of gastroschisis infants.Methods
A three center, retrospective cohort study (1992-2013) with linked fetal/neonatal gastroschisis data was conducted. The primary outcome measure was time to full enteral feeds (a surrogate measure for bowel function) and secondary outcome measure was length of hospital stay. Analysis included Mann-Whitney and Cox regression.Results
Of 500 patients included in the study, 69 (GA at birth 34 [25-38] weeks) received antenatal corticosteroids and 431 (GA at birth 37 [31-41] weeks) did not. Antenatal corticosteroids had no effect on the rate of reaching full feeds (Hazard ratio HR 1.0 [95% CI: 0.8-1.4]). However, complex gastroschisis (HR 0.3 [95% CI: 0.2-0.4]) was associated with an increased time to reach full feeds and later GA at birth (HR 1.1 per week increase in GA [95% CI: 1.1-1.2]) was associated with a decreased time to reach full feeds.Conclusion
Maternal antenatal corticosteroids use, under current antenatal steroid protocols, in gastroschisis is not associated with an improvement in neonatal outcomes such as time to full enteral feeds or length of hospital stay. 相似文献743.
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747.
L M Simon K László M Kotormán A Vértesi K Bagi J Nemcsók 《Journal of environmental science and health. Part. B》1999,34(5):819-828
The effects of pyrethroid pesticides (deltamethrin, permethrin and cypermethrin) and an organophosphate ester (methidation) on the activities of carp trypsin, alpha-chymotrypsin, carboxypeptidase A and lipase were studied. The enzymes were isolated from the gastrointestinal tract and the effects of the pesticides were investigated during incubation for 5 min. The activity of trypsin was influenced only slightly by the presence of deltamethrin and methidation, whereas permethrin and cypermethrin caused significant inhibition. The pyrethroid pesticides at lower concentrations resulted in a slight activation of alpha-chymotrypsin. Methidation inhibited the alpha-chymotrypsin activity by about 20%. These pesticides modified the lipase activity to a lesser extent; the highest inhibition was measured with cypermethrin. The carboxypeptidase A activity was inhibited by both pyrethroid pesticides and methidation. The results suggest that these pesticides might interact with the active conformation of the studied hydrolytic enzymes, resulting in changes in their activities. 相似文献
748.
Horst Rakel Simon Gerrard Graham Piggott Gordon Crick 《Journal of Safety Research》1998,29(4):235-247
This study reports on the development of an evaluation methodology for assessing quantitatively and qualitatively the effectiveness of seminar and mass-mailing contact techniques. These techniques are used to augment traditional health and safety inspections at commercial and industrial premises in the United Kingdom. One of the major findings is that specific aims and objectives for the intervention should be developed prior to the communication exercise. This is crucial for any subsequent measurement of effectiveness, as the intended effect needs to be considered before the communication exercise takes place. Developing more systematic approaches to evaluation is an important step in helping to learn from previous experiences, that is, to build upon the foundations of good practice and avoid repeating mistakes. In time the results of systematic evaluations can be used to inform future policy making, which may help to create more effective risk reduction strategies. 相似文献
749.
Three decades ago, the observation that first trimester fetuses with excess fluid accumulation at the back of the neck were more likely to be aneuploid, gave rise to a new era of prenatal screening. The nuchal translucency (NT) measurement in combination with serum biomarkers and maternal age, resulted in the first trimester combined screening (FTCS) program. The introduction of noninvasive prenatal testing (NIPT) over the past decade has introduced the option for parents to receive highly sensitive and specific screening information for common trisomy from as early as 10 weeks gestation, altering the traditional pathway FTCS pathway. The retention of the 11–13-week NT ultrasound remains important in the detection of structural anomalies; however, the optimal management of pregnancies with a low-risk NIPT result and an isolated increased NT measurement in an era of advanced genomic testing options is a new dilemma for clinicians. For parents, the prolonged period between the initial diagnosis in first trimester, and prognostic information at each successive stage of investigations up to 22–24 weeks, can be emotionally challenging. This article addresses the common questions from parents and clinicians as they navigate the uncertainty of having a fetus diagnosed with an increased NT after a low-risk NIPT result and presents suggested approaches to management. 相似文献
750.
Miriam Fluckiger George D. Jackson Peter Nichols Patti Virtue Adam Daw Simon Wotherspoon 《Marine Biology》2008,154(2):363-372
Fatty acid analysis is an alternative dietary investigation tool that complements the more traditional techniques of stomach
content and faecal analysis that are often subject to a wide range of biases. In applying fatty acid analysis to ecosystem
studies, it is important to have an understanding of the effect diet has on the fatty acid profile of the predator. A feeding
experiment, using crustacean and fish as prey for the European cuttlefish Sepia officinalis, was conducted to evaluate the effect of prey fatty acids on the fatty acid profile of this marine predator. Cuttlefish were
fed on a fish diet for the first 29 days, and then changed to a crustacean diet for a further 28 days. Another group of cuttlefish
was fed on a crustacean diet for the first 29 days, and then changed to a fish diet for a further 28 days. An analysis of
the cuttlefish digestive gland showed that the fatty acid profile reflected that of the prey, with cuttlefish on a crustacean
diet being clearly distinguishable from the cuttlefish on a fish diet. Cuttlefish fed on a fish diet for 29 days prior to
the switch in diet were comparatively higher in 16:0, AA, 20:1ω9, DPA6, DHA, 22:4ω6 and DPA3 than those fed on crustaceans.
Cuttlefish fed on a crustacean diet for 29 days prior to the switch in diet were comparatively higher in 17:1ω8, 18:1ω9, 18:2ω6,
18:1ω7, EPA and 20:2ω6 than those fed on fish. Following a change in diet, the fatty acid profile of the cuttlefish digestive
gland reflected that of the new diet within 14 days. The results confirm that the fatty acid profile of the cuttlefish digestive
gland clearly reflects the profile of its recent diet. It also shows that the digestive gland may not be an organ that accumulates
dietary lipids for long-term storage, but rather is an organ where lipids are rapidly being turned over and potentially excreted. 相似文献