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71.
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72.
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
73.
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
74.
Objective
to review the literature around what is considered to be a good midwife and in particular what women value in a midwife, in order to identify the gaps in the evidence for future research.Design
this paper reviews the research in the area of interest over the past 30 years. The literature search focused on the concept of good midwife using synonyms and antonyms. The inclusion criteria included language (English or Italian). The examined databases were Medline, Maternity and Infant Care, Applied Social Sciences Index and Abstract and CINAHL.Setting
studies conducted in high-income countries were taken into account. A focused review of papers which explicitly investigated what a good midwife means and a thematic analysis on what women value in a midwife were carried out.Participants
different standpoints have been considered (midwives, student midwives, women and their partners), focusing in particular on women viewpoint.Findings
the literature review reveals information about what is considered to be a good midwife from a range of perspectives and what women value in a midwife. A good midwife should possess several attributes: theoretical knowledge, professional competencies, personal qualities, communication skills and moral/ethical values. According to the thematic analysis around what childbearing women value in a midwife, frequent key-themes emerging from the literature were: support, possibility of choice, feeling in control and having appropriate information.Key conclusions
the meaning of good midwife might change according to different actors involved in midwifery care and there is no agreement on the definition of what constitutes a good midwife. Furthermore, it is not clear if what women value in a good midwife corresponds to the midwives' perception of themselves as good professionals. There is a dearth of information around women's expectations and experiences specifically of a good midwife, and even less around whether this changes according to where they give birth.Implications for practice
this literature review seeks to stimulate debate and reflection among midwives and professionals involved in the childbearing event, in order to fulfil women's expectations of their midwife and increase their satisfaction with the birth experience. The identification of the gaps in the evidence provided the starting point and allowed the development of research questions and methodology for an ongoing doctoral research. On the basis of the gaps in the evidence, the doctoral research will explore and seek to explain nulliparous women's expectations and experiences of a good midwife in the context of different planned place of birth, using a Grounded Theory methodology. It is also expected that the findings of this literature review will stimulate additional research in this area to ultimately inform midwifery practice and midwifery educational programmes. 相似文献75.
76.
Objective
to gain a deeper understanding of the experience of professional and social support during pregnancy and childbirth among women with intellectual disability (ID) in Sweden.Design/setting
an interview study among 10 women with ID, who had given birth within seven years. Two interviews were performed with each woman and data were analysed with qualitative content analysis.Findings
the overarching theme was: Professional and social support enhances maternal well-being in women with intellectual disability. The women described that the midwife and other caregivers contributed to their own insights and supported their mother-to-be process. They were mostly satisfied with the professional care and support during pregnancy and childbirth, based on aspects such as continuity, competence and professional experience of the midwives but also professional approach and working methods. Dissatisfaction and confusion occurred when questions were left unanswered or when the women?s special needs were not taken into consideration. Family members, friends and colleagues could also have a supporting role and, together with the health staff, contribute to the well-being of the woman.Conclusions
if professional support and care from midwives and other caregivers is adapted to the special needs of women with ID, it contributes to new insights, enhances well-being and supports the process of becoming a mother. Midwife-led continuity of care together with continuous social support should be offered to pregnant women with ID during pregnancy and childbirth. 相似文献77.
Objective
to investigate midwives' knowledge of, attitudes towards and experiences of caring for women with intellectual disability (ID) during pregnancy and childbirth.Design/setting
a cross-sectional study among six hundred midwives working at antenatal care and labour wards in Sweden.Results
more than four out of five (81.5%) midwives had experience of caring for women with ID. Almost all midwives (97.1%) reported that caring for women with ID is different from caring for women without ID. Almost one-half (47.3%) had not received any education about pregnancy and delivery of women with ID, and a majority of the midwives (95.4%) requested evidence-based knowledge of women with ID in relation to childbirth. High proportion (69.7%) of the midwives were of the opinion that women with ID cannot satisfactorily manage the mother role, and more than one-third (35.7%) of the midwives considered that women with ID should not be pregnant and give birth at all. Most midwives partly/totally agreed that children of women with ID should grow up with their parents supported by the social authorities, but nearly one-fifth (19.1%) partly/totally agreed that the children should grow up in foster care.Conclusions
even if the majority of midwives had experience of caring for women with ID, they were uncertain about how to adapt and give advice and they needed more knowledge about these women. Some midwives had negative attitudes towards childbearing among women with ID. Health Service providers should encourage midwives to update their knowledge and provide supportive supervision in midwifery care for women with ID. 相似文献78.
79.
T2 values in the human brain: comparison with quantitative assays of iron and ferritin 总被引:8,自引:0,他引:8
Chen JC; Hardy PA; Clauberg M; Joshi JG; Parravano J; Deck JH; Henkelman RM; Becker LE; Kucharczyk W 《Radiology》1989,173(2):521-526
Magnetic resonance (MR) imaging with a whole-body imager was performed in 10 fresh, unfixed whole human brains selected randomly from cadavers. All subjects were neurologically intact before death. T2 time constants were measured within the caudate nucleus, putamen, globus pallidus, cortical gray matter, subcortical white matter, and optic radiation. These regions were then excised, and T2 values were measured again with a 1.5-T MR spectrometer. Quantitative assays of iron, ferritin, and protein from these areas were then performed. Iron concentration varied significantly among brain regions, whereas ferritin and protein concentrations were constant among brain regions and among individuals. Neither iron nor ferritin concentration showed any consistent correlation with T2 values. Histologic examination of brain micro-sections with iron- and ferritin-specific stains of demonstrated poor correlation with biochemical assays of ferritin and iron concentrations. Results indicate that T2 values correlate poorly with iron and ferritin concentrations found in neurologically intact brains. 相似文献
80.