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Mitochondria (mt) play an important role in both apoptosis and haem synthesis. The present study was conducted to determine DNA mutations in mitochondrial encoded cytochrome c-oxidase I and II genes. Bone marrow (BM) biopsy and aspirate, peripheral blood (PB) and buccal smear samples were collected from 20 myelodysplastic syndrome (MDS) patients and 10 age-matched controls. Cytochrome c-oxidase I (CO I) and II (CO II) genes were amplified using polymerase chain reaction and sequenced. CO I mutations were found in 13/20 MDS patients and the CO II gene in 2/10 normal and 12/20 MDS samples, irrespective of MDS subtype. Mutations were substitutional, deletional and insertional. CO I mutations were most common at nucleotide positions 7264 (25%) and 7289 (15%), and CO II mutations were most common at nucleotide positions 7595 (40%) and 7594 (30%), suggesting the presence of potential 'hot-spots'. Mutations were not found in buccal smears of MDS patients and were significantly higher in MDS samples compared with age-matched controls in all cell fractions (P < 0.05), with bone marrow high-density fraction (BMHDF) showing a higher mutation rate than other fractions (P < 0.05). MDS marrows showed higher levels of apoptosis than normal controls (P < 0.05), and apoptosis in BMHDF was directly related to cytochrome c-oxidase I gene mutations (P < 0.05). Electron microscopy revealed apoptosis affecting all haematopoietic lineages with highly abnormal, iron-laden mitochondria. These results suggest a role for mt-DNA mutations in the excessive apoptosis and resulting cytopenias of MDS patients.  相似文献   
94.
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95.
Severe folate deficiency in pregnancy may mimick HELLP syndrome as there are similar features in both. Proper diagnosis is important as far as the prognosis and management are concerned. Two cases of severe folate deficiency occuring in multigravid women mimicking HELLP syndrome are reported below with review of literature.  相似文献   
96.
With the causal link between specific types of human papillomavirus (HPV) and cervical cancer firmly established, efforts have turned to assessing the relative merits of offering HPV testing in screening, triage, and posttreatment management. Many unanswered questions remain, but a growing body of evidence supports a role for HPV testing in cervical cancer prevention programs. Already, clinical centers that serve thousands of women in Europe and the United States have incorporated HPV DNA tests in triage algorithms.  相似文献   
97.
A community based study was Conducted in the rural areas of Udupi taluk, Karnataka state of South India to identify the socio-demographic, maternal and obstetric determinants of low birth weight. All singleton live births that occurred in the study area during a one year period (October 1991 to September 1992) were included. A total of 2919 singleton child-mother pairs formed the basis of the analysis. Information about social, demographic and economic conditions of the families; maternal factors such as age, parity, quality of antenatal care and previous obstetric history were collected by interviewing the mothers and family members and verifying the available medical records through the field investigators especially recruited and trained for this purpose. Data was analyzed using multiple logistic regression model. Primis, elderly mothers and mothers who had not received good quality antenatal care were found to be more at risk of having low birth weight babies. Other significant determinants were family custom, socio-economic status and environmental sanitation.  相似文献   
98.
Childhood vitiligo differs from adult vitiligo in many clinical parameters. The objective of the current study was to study the clinicoepidemiologic profile of childhood vitiligo and to compare various clinical characteristics of childhood‐ and later‐onset vitiligo. The clinical presentation of vitiligo was examined and analyzed in 762 individuals attending the Dermatology Clinic of Government Medical College, Haldwani, a referral center for the Kumaun region of Uttarakhand state, India, between January 2006 and December 2010. Of the 762 individuals with vitiligo, 268 (35.2%) were children: 152 (56.7%) female and 116 (43.3%) male. The mean age of onset of vitiligo was 6.9 years. A family history of vitiligo was found in 24.3% of children. The most common site of onset was the head and neck (36.9%), followed by the lower limbs and trunk. The most common type of vitiligo observed was acrofacial vitiligo (38.1%), followed by vulgaris, segmental, focal, and mucosal. Leukotrichia was observed in 32.5% of children and Koebner's phenomenon in 24.3%. On comparison of childhood‐ and later‐onset vitiligo, there were statistically significant differences (p < 0.05) in sex, family history, type of vitiligo (segmental and vulgaris), and site of onset. Atopic dermatitis was one of the important cutaneous diseases associated with childhood‐onset vitiligo. Thirty‐five percent of all patients with vitiligo were children (≤12 yrs). Childhood‐onset vitilgo differs from later‐onset vitiligo in many clinical parameters such as sex, family history, types of vitiligo, and sites of onset.  相似文献   
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Placenta increta complicated pregnancy in a woman with a history of endometrial resection. Placentation in women with prior endometrial ablation carries a high risk for placenta accreta, increta and percreta. Contraceptive measures must be implemented after endometrial ablation and pursued until proven menopause, even in women who develop amenorrhoea postoperatively.  相似文献   
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