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101.
Catherine Angell RM BSc PhD Jo Alexander RM MTD PhD Jane A. Hunt RGN RSCN PhD 《分娩》2011,38(4):346-353
Abstract: Background: Breastfeeding is the optimal feeding method for human infants. In the United Kingdom some women do not initiate breastfeeding, and many commence formula milk feeding after a brief period of breastfeeding. Infant feeding perceptions may develop early in life, and this research aimed to explore infant feeding awareness among primary school children as a first step toward informing appropriate health education interventions. Method: Fifty‐six children aged 5/6, 7/8, and 10/11 years were recruited from three schools in southern England. Children were shown a series of drawings, and were read a story about a hungry newborn baby. A creative method, “draw, write and tell,” was developed for this research. Children were asked to finish the story, showing how they thought the baby might be fed. They were given the opportunity to verbally interpret their work. A constant comparison method was used to analyze the data. Results: Children were aware of formula milk, breastfeeding, and solid foods. Formula milk feeding was referred to more frequently than breastfeeding. Some children combined feeding methods. Children appeared to have gained their awareness in various settings. Conclusions: Children have a range of perceptions around infant feeding. They appear receptive to new ideas on the subject while of primary school age. An opportunity for education in primary schools arises to present breastfeeding to children as a normal way to feed a baby, but it is vital that education is evidence based and any interventions are evaluated. (BIRTH 38:4 December 2011) 相似文献
102.
Carol Bedwell LLB RM Research Midwife Therese Dowswell PhD Research Fellow James P. Neilson MD FRCOG Professor of Obstetrics Gynaecology Tina Lavender PhD RM Professor of Midwifery 《Midwifery》2011,27(5):e141
Objective
to assess the effects of transcutaneous electrical nerve stimulation (TENS) for pain relief in labour.Search methods
studies were identified from a search of the Cochrane Pregnancy and Childbirth Group’s Trials Register (November 2008).Selection criteria
randomised controlled trials comparing women receiving TENS for pain relief in labour vs routine care or placebo devices. All types of TENS machines were included.Data collection and analysis
two review authors assessed all trials identified by the search strategy, carried out data extraction and assessed risk of bias.Results
14 studies including 1256 women were included: 11 examined TENS applied to the back, two to acupuncture points and one to the cranium. Overall, there was little difference in satisfaction with pain relief or in pain ratings between TENS and control groups, although women receiving TENS to acupuncture points were less likely to report severe pain (risk ratio 0.41, 95% confidence interval 0.32–0.55). The majority of women using TENS would use it again in a future labour. There was no evidence that TENS had any impact on interventions and outcomes in labour. There was little information on outcomes for mothers and infants. No adverse events were reported.Conclusions
there is only limited evidence that TENS reduces pain in labour and it does not seem to have any impact on other outcomes for mothers or infants. The use of TENS at home in early labour has not been evaluated. Although the guidelines of the National Institute for Health and Clinical Excellence recommend that TENS should not be offered to women in labour, women appear to be choosing it and midwives are supporting them in their choice. Given the absence of adverse effects and the limited evidence base, it seems unreasonable to deny women that choice. More robust studies of effectiveness are needed. 相似文献103.
Della A. Forster Dip.App.Sci. BHealth.Sci. MMid PhD Senior Research Fellow Midwifery Consultant Kerri McEgan RN RM Unit Manager Rachael Ford BNurs Clinical Midwife Research Scholarship Fellow Anita Moorhead RN RM Clinical Midwifery Consultant Gillian Opie MBBS Neonatal Paediatrician Susan Walker MBBS MD Associate Professor Director of Perinatal Medicine Cath McNamara BA Grad Cert Diab Ed Diabetic Educator 《Midwifery》2011,27(2):209-214
Objective
infants of women with diabetes in pregnancy are at increased risk of hypoglycaemia. If the infant's blood glucose is low and the mother is unable to breast feed/provide sufficient expressed breast milk, infants are often given formula. Some hospitals encourage women with diabetes to express breast milk before birth. However, there is limited evidence for this practice, including its impact on labour and birth, e.g. causing premature birth may be a concern. A pilot study was undertaken to establish the feasibility of conducting an adequately powered randomised controlled trial to evaluate this practice.Design
consecutive eligible women with pre-existing or gestational diabetes (requiring insulin), planning to breast feed and attending the study hospital were offered participation. Inclusion criteria: 34-36 weeks of gestation; singleton pregnancy; cephalic presentation; and able to speak, read and write in English. Exclusion criteria: history of spontaneous preterm birth, antepartum haemorrhage, placenta praevia and suspected fetal compromise. Women were encouraged to express colostrum twice a day from 36 weeks of gestation, and advised how to store the colostrum, which was frozen for their infant's use after birth. They were asked to keep a diary documenting their expressing. Data: demographic questionnaire, telephone interview at six and 12 weeks postpartum and medical record data.Setting
a public, tertiary, women's hospital in Melbourne, Australia.Participants
43 women with diabetes in pregnancy (requiring insulin).Findings
cardiotocographs were undertaken after the first expressing episode and none of the infants showed any sign of fetal compromise. Forty per cent of infants received formula in the 24 hours postpartum. The proportion of infants receiving any breast milk at six weeks was 90%, and this decreased to 75% at 12 weeks. No women showed evidence of hypoglycaemia post expressing. The intervention was positively received by most women; 95% said that they would express antenatally again if the practice proved to be beneficial. The amount of colostrum varied according to the number of expressions, the length of time in the study and the time spent expressing, with a median of 14 days expressing and 39.6 ml of colostrum obtained.Key conclusions
the small number of women in this pilot was not an adequate number to examine safety or efficacy, but this study does provide evidence that it would be feasible and desirable to conduct a randomised controlled trial of antenatal milk expressing for women with diabetes requiring insulin in pregnancy.Implications for practice
it is important that this widespread practice undergoes rigorous evaluation to assess both efficacy and safety. Until such evidence is available, the authors suggest that the routine encouragement of antenatal milk expressing in women with diabetes in pregnancy should cease. 相似文献104.
Duncan A. A. MacLaren David I. G. Wilson Philip Winn 《Brain structure & function》2016,221(3):1481-1497
Cholinergic neurons within the pedunculopontine tegmental nucleus have been implicated in a range of functions, including behavioral state control, attention, and modulation of midbrain and basal ganglia systems. Previous experiments with excitotoxic lesions have found persistent learning impairment and altered response to nicotine following lesion of the posterior component of the PPTg (pPPTg). These effects have been attributed to disrupted input to midbrain dopamine systems, particularly the ventral tegmental area. The pPPTg contains a dense collection of cholinergic neurons and also large numbers of glutamatergic and GABAergic neurons. Because these interdigitated populations of neurons are all susceptible to excitotoxins, the effects of such lesions cannot be attributed to one neuronal population. We wished to assess whether the learning impairments and altered responses to nicotine in excitotoxic PPTg-lesioned rats were due to loss of cholinergic neurons within the pPPTg. Selective depletion of cholinergic pPPTg neurons is achievable with the fusion toxin Dtx-UII, which targets UII receptors expressed only by cholinergic neurons in this region. Rats bearing bilateral lesions of cholinergic pPPTg neurons (>90 % ChAT+ neuronal loss) displayed no deficits in the learning or performance of fixed and variable ratio schedules of reinforcement for pellet reward. Separate rats with the same lesions had a normal locomotor response to nicotine and furthermore sensitized to repeated administration of nicotine at the same rate as sham controls. Previously seen changes in these behaviors following excitotoxic pPPTg lesions cannot be attributed solely to loss of cholinergic neurons. These findings indicate that non-cholinergic neurons within the pPPTg are responsible for the learning deficits and altered responses to nicotine seen after excitotoxic lesions. The functions of cholinergic neurons may be related to behavioral state control and attention rather than learning. 相似文献
105.
Devendra Kumar Pandey Tabarak Malik Abhijit Dey Joginder Singh RM Banik 《African journal of traditional, complementary, and alternative medicines》2014,11(2):439-446
Background
Gloriosa superba produces an array of alkaloids including colchicine, a compound of interest in the treatment of various diseases. The tuber of Gloriosa superba is a rich source of colchicine which has shown anti-gout, anti-inflammatory, and anti-tumor activity. However, this promising compound remains expensive and Gloriosa superba is such a good source in global scale. Increase in yield of naturally occurring colchicine is an important area of investigation.Materials and Methods
The effects of inoculation by four arbuscular mycorrhizal (AM), fungi, Glomus mossae, Glomus fasciculatum, Gigaspora margarita and Gigaspora gilmorei either alone or supplemented with P-fertilizer, on colchicine concentration in Gloriosa superba were studied. The concentration of colchicine was determined by high-performance thin layer chromatography.Results
The four fungi significantly increased concentration of colchicine in the herb. Although there was significant increase in concentration of colchicine in non-mycorrhizal P-fertilized plants as compared to control, the extent of the increase was less compared to mycorrhizal plants grown with or without P-fertilization. This suggests that the increase in colchicine concentration may not be entirely attributed to enhanced P-nutrition and improved growth. Among the four AM fungi Glomus mossae was found to be best. The total colchicine content of plant (mg / plant) was significantly high in plants inoculated with Glomus mossae and 25 mg kg−1phosphorus fertilizer (348.9 mg /plant) while the control contain least colchicine (177.87 mg / plant).Conclusion
The study suggests a potential role of AM fungi in improving the concentration of colchicine in Gloriosa superba tuber. 相似文献106.
JD Roberts JC Herkert J Rutberg SM Nikkel ACP Wiesfeld D Dooijes RM Gow JP van Tintelen MH Gollob 《Clinical genetics》2013,83(5):452-456
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited myocardial disease that predominantly affects the right ventricle and is associated with ventricular arrhythmias that may lead to sudden cardiac death. Mutations within at least seven separate genes have been identified to cause ARVC, however a genetic culprit remains elusive in approximately 50% of cases. Although negative genetic testing may be secondary to pathogenic mutations within undiscovered genes, an alternative explanation may be the presence of large deletions or duplications involving known genes. These large copy number variants may not be detected with standard clinical genetic testing which is presently limited to direct DNA sequencing. We describe two cases of ARVC possessing large deletions involving plakophilin‐2 (PKP2) identified with microarray analysis and/or multiplex ligation‐dependent probe amplification (MLPA) that would have been classified as genotype negative with standard clinical genetic testing. A deletion of the entire coding region of PKP2 excluding exon 1 was identified in patient 1 and his son. In patient 2, MLPA analysis of PKP2 revealed deletion of the entire gene with subsequent microarray analysis demonstrating a de novo 7.9 Mb deletion of chromosome 12p12.1p11.1. These findings support screening for large copy number variants in clinically suspected ARVC cases without clear disease causing mutations following initial sequencing analysis. 相似文献
107.
Follicular density in ovarian biopsy of infertile women: a novel method to assess ovarian reserve 总被引:4,自引:15,他引:4
Lass A; Silye R; Abrams DC; Krausz T; Hovatta O; Margara R; Winston RM 《Human reproduction (Oxford, England)》1997,12(5):1028-1031
The ageing ovary appears to be characterized by depletion of primordial
follicles. The relationship between infertility and the number of follicles
in the ovarian cortex is not known. Moreover, there are no accurate markers
or clinical methods to predict the decline in ovarian reserve. This study
investigates the correlation between early follicular follicle stimulating
hormone, ovarian size and follicular density in 60 infertile women aged
19-45 years (mean = 34.4 +/- 5.5). An ovarian biopsy was taken from each
patient while performing diagnostic laparoscopy (n = 28) or laparotomy for
tubal surgery or myomectomy (n = 32). The median number of follicles was
similar in tubal and unexplained infertility patients (9.5 versus 5.5).
Increasing age showed a significant negative correlation with follicular
density and ovarian volume (r = -0.46, P = 0.0003;. r = -0.43, P = 0.0016,
respectively). In women > or = 35 years of age the ovarian volume showed
a strong correlation with follicular density (r = 0.71, P < 0.0001). Our
results indicate that infertile women in their late thirties and over have
a decreased ovarian reserve which could possibly be predicted by ovarian
volume measurement. Ovarian biopsy may have a place as part of infertility
evaluation in older women.
相似文献
108.
The pedunculopontine tegmental nucleus (PPTg) interacts with anatomical systems thought to be involved in mediating sensitisation of the locomotor response to repeated d-amphetamine. The PPTg has direct and indirect connections with the nucleus accumbens and prefrontal cortex, and also influences midbrain dopamine activity through direct projections to substantia nigra and ventral tegmental area. In this experiment, the development of behavioural sensitisation to the locomotor stimulant effects of repeated d-amphetamine was examined in rats bearing excitotoxic lesions of the PPTg, and sham-lesioned controls. Rats were given repeated d-amphetamine (1.5 mg/kg i.p.) treatment in an on-off procedure, with saline and d-amphetamine given on alternate days, such that rats received a total of seven d-amphetamine and seven saline treatments. Locomotor responses were measured in photocell cages. On the first day of d-amphetamine treatment, there was no difference between excitotoxin and sham-lesioned rats. Development of sensitisation to the locomotor stimulant effects of d-amphetamine was delayed in PPTg-lesioned rats, relative to the sham-lesioned control rats. However, there was no difference between lesion and control groups in the locomotion seen on saline-treatment days. These data suggest that the PPTg is involved in the development of behavioural sensitisation to the locomotor stimulant effects of repeated d-amphetamine, and indicate that traditional striatal circuitry models of the mechanisms underlying sensitisation should be extended to include the PPTg. 相似文献
109.
Richard M Winn Cristina Gil-Lamaignere Avgi Maloukou Emmanuel Roilides 《Medical mycology》2003,41(6):503-509
Fusarium spp. are emerging as important causes of invasive fungal infections. They tend to have decreased susceptibility to antifungal agents, making host defences very important. The ability of human phagocytes to cause damage to hyphae of Fusarium solani, F. oxysporum and Verticillium nigrescens, a mould with very low pathogenicity, was assessed using the 2,3-bis[2-methoxy-4-nitro-5-sulphophenyl]2H-tetrazolium-5-carboxanilide (XTT) metabolic assay. The oxidative burst, evidenced as superoxide anion (O2-) production, of phagocytes in response to hyphae was also investigated, as well as phagocytosis of conidia by monocyte (MNC)-derived macrophages (MDM). Hyphal damage by polymorphonuclear leukocytes (PMNL) and MNC showed a linear trend increasing with effector cell:target cell (E:T) ratio. Although no significant differences were observed for PMNL, MNC-induced damage to F. solani hyphae was lower than that seen with F. oxysporum hyphae at an E:T ratio of 20:1 and with V. nigrescens hyphae at ratios of 1:1, 5:1 and 20:1 (P < 0.05). In contrast, levels of O2- production by phagocytes in response to F. oxysporum were lower than those induced in response to the other fungi (P < 0.01). The average number of V. nigrescens conidia ingested by MDM was higher than that of conidia of the other fungi (P < 0.01). Phagocytes respond to the test fungi differentially, with F. solani being the least susceptible to damage by MNC. This may correlate with the observation that, compared to the other fungi studied, it causes a relatively high incidence of infections in neutropenic patients. 相似文献
110.
Winn RN Majeske AJ Jagoe CH Glenn TC Smith MH Norris MB 《Environmental and molecular mutagenesis》2008,49(3):173-184
To address the need for improved approaches to study mutations transmitted to progeny from mutagen-exposed parents, we evaluated lambda transgenic medaka, a small fish that carries the cII mutation target gene, as a new model for germ cell mutagenesis. Mutations in the cII gene in progeny derived from ethyl-nitrosourea (ENU)-exposed males were readily detected. Frequencies of mutant offspring, proportions of mosaic or whole body mutant offspring, and mutational spectra differed according to germ cell stage exposed to ENU. Postmeiotic germ cells (spermatozoa/late spermatids) generated a higher frequency of mutant offspring (11%) compared to premeiotic germ cells (3.5%). Individuals with cII mutant frequencies (MF) elevated more than threefold above the spontaneous MF (3 x 10(-5)) in the range of 10(-4) to 10(-3) were mosaic mutant offspring, whereas those with MFs approaching 1 x 10(-2) were whole body mutant offspring. Mosaic mutant offspring comprised the majority of mutant offspring derived from postmeiotic germ cells, and unexpectedly, from spermatogonial stem cells. Mutational spectra comprised of two different mutations, but at identical sites were unusual and characteristic of delayed mutations, in which fixation of a second mutation was delayed following fertilization. Delayed mutations and prevalence of mosaic mutant offspring add to growing evidence that implicates germ cells in mediating processes postfertilization that contribute to genomic instability in progeny. This model provides an efficient and sensitive approach to assess germ cell mutations, expands opportunities to increase understanding of fundamental mechanisms of mutagenesis, and provides a means for improved assessment of potential genetic health risks. 相似文献