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211.
Bankole A Sedgh G Oye-Adeniran BA Adewole IF Hussain R Singh S 《Journal of biosocial science》2008,40(2):247-268
This study used data from a community-based survey to examine women's experiences of abortion in Nigeria. Fourteen percent of respondents reported that they had ever tried to terminate a pregnancy, and 10% had obtained an abortion. The majority of women who sought an abortion did so early in the pregnancy. Forty-two percent of women who obtained an abortion used the services of a non-professional provider, a quarter experienced complications and 9% sought treatment for complications from their abortions. Roughly half of the women who obtained an abortion used a method other than D&C or MVA. The abortion prevalence and conditions under which women sought abortions varied by women's socio-demographic characteristics. Because abortion is illegal in Nigeria except to save the woman's life, many women take significant risks to terminate unwanted pregnancies. Reducing the incidence of unwanted pregnancy and unsafe abortion can significantly impact the reproductive health of women in Nigeria. 相似文献
212.
Hussain K 《Hormone research》2008,69(1):2-13
Hyperinsulinaemic hypoglycaemia is a cause of persistent hypoglycaemia in the neonatal and infancy periods. Prompt recognition and management of patients with hyperinsulinaemic hypoglycaemia are essential, if brain damage and long-term neurological sequelae are to be avoided. Hyperinsulinaemic hypoglycaemia can be transient, prolonged, or persistent (congenital). Advances in the fields of molecular biology, genetics, and pancreatic beta-cell physiology are beginning to provide novel insights into the mechanisms causing congenital forms of hyperinsulinism. So far mutations in six different genes have been described that lead to unregulated insulin secretion. The histological differentiation of focal and diffuse congenital hyperinsulinism has radically changed the surgical approach to this disease. Until recently, highly invasive investigations were performed to localize the focal lesion, but recent experience with (18)F-L-dopa positron emission tomography scanning suggests that this technique is highly sensitive for differentiating diffuse from focal disease as well as for accurately locating the focal lesion. Despite recent advances, the genetic basis of congenital hyperinsulinism is still unknown in about 50% of the patients, and the management of medically unresponsive diffuse disease remains a real challenge. 相似文献
213.
Valuing mangrove ecosystem services: linking nutrient retention function of mangrove forests to enhanced agroecosystem production 总被引:1,自引:0,他引:1
Mangroves are highly productive wetland ecosystems strategically located at the interface between land and sea. They play
an important role in the biogeochemical cycles of the coastal environment, acting as sources of nutrients to adjacent marine
and terrestrial ecosystems through active and passive transport. We examined the nutrient contents in mangrove and nonmangrove
soils in and around the Bhitarkanika National Park, India and assessed whether the local agricultural producers were aware
of and placed a value on this contribution of mangrove forests in enhancing agroecosystem productivity. Soil samples from
both mangrove and nonmangrove areas were analysed and quantity of organic carbon, total nitrogen, available phosphorus and
potassium were derived. The replacement cost method was used to derive the value of nutrients in mangrove soils. We estimated
that each hectare of mangrove contains additional nutrients worth US$232.49 in comparison to nonmangrove areas. The difference
in nutrient content in mangrove versus nonmangrove areas gave the value of US$3.37 million for the nutrients in 145 km2 of mangrove forests. The agricultural producers were aware that mangrove forests act as a source of nutrients and were willing
to pay a higher price for the land adjoining mangrove forests. Around 92% of the producers ranked nutrient retention as a
secondary function of mangrove forests. Despite crop depredation from wild ungulates and conflict with salt water crocodiles
the agriculturist finds the benefit to cost ratio of mangrove forests high and more than 76% were in favour of mangrove restoration.
This study provides an opportunity to highlight the importance of mangrove ecosystems to the livelihoods of the local people
and the urgent need to sustain these through proper policy and market interventions. 相似文献
214.
Schwinté P Foerstendorf H Hussain Z Gärtner W Mroginski MA Hildebrandt P Siebert F 《Biophysical journal》2008,95(3):1256-1267
Fourier transform infrared spectroscopy was used to analyze the chromophore structure in the parent states Pr and Pfr of plant phytochrome phyA and the respective photoproducts lumi-R and lumi-F. The spectra were obtained from phyA adducts assembled with either uniformly or selectively isotope-labeled phytochromobilin and phycocyanobilin. The interpretation of the experimental spectra is based on the spectra of chromophore models calculated by density functional theory. Global 13C-labeling of the tetrapyrrole allows for the discrimination between chromophore and protein bands in the Fourier transform infrared difference spectra. All infrared difference spectra display a prominent difference band attributable to a stretching mode with large contributions from the methine bridge between the inner pyrrole rings (B-C stretching). Due to mode coupling, frequencies and isotopic shifts of this mode suggest that the Pr chromophore may adopt a distorted ZZZssa or ZZZasa geometry with a twisted A-B methine bridge. The transition to lumi-R is associated with only minor changes of the amide I bands indicating limited protein structural changes during the isomerization site of the C-D methine bridge. Major protein structural changes occur upon the transition to Pfr in which the chromophore adopts a ZZEssa or ZZEasa-like state. In addition, specific interactions with the protein alter the structure of the B-C methine bridge as concluded from the substantial downshift of the respective stretching mode. These interactions are removed during the photoreaction to lumi-F (ZZE→ZZZ), which involves only small protein structural changes. 相似文献
215.
Vijeshwar Verma Andrija Smelcerovic Sebastian Zuehlke Mir Abid Hussain Syed Mudasir Ahmad Thorsten Ziebach Ghulam Nabi Qazi Michael Spiteller 《Biochemical Systematics and Ecology》2008
The content of hypericins (hypericin and pseudohypericin), hyperforin, and flavonoids (rutin, hyperoside, quercitrin, and quercetin) and genetic profiles of eight accessions of Hypericum perforatum L., collected from different locations in India, have been determined. The secondary metabolite content was determined using a highly selective LC/MS/MS method. Pearson and Spearman's correlation coefficient were used to investigate the relationships between the secondary metabolites and a significant positive correlation was found between hypericin and pseudohypericin contents. Genetic profiling was undertaken using the random amplification of polymorphic DNA (RAPD) and single sequence repeat (SSR) methods. Among the 49 random primers used for the initial screening, only nine yielded polymorphic RAPD profiles. The SSR analysis shows that seven out of the 11 primers were polymorphic. There exists only a partial correlation between the chemical content and genetic profiling data among the accessions under study. 相似文献
216.
217.
218.
Clarke B Demont E Dingwall C Dunsdon R Faller A Hawkins J Hussain I MacPherson D Maile G Matico R Milner P Mosley J Naylor A O'Brien A Redshaw S Riddell D Rowland P Soleil V Smith KJ Stanway S Stemp G Sweitzer S Theobald P Vesey D Walter DS Ward J Wayne G 《Bioorganic & medicinal chemistry letters》2008,18(3):1017-1021
This paper describes the discovery of non-peptidic, potent, and selective hydroxy ethylamine (HEA) inhibitors of BACE-1 by replacement of the prime side of a lead di-amide 2. Inhibitors with nanosmolar potency and high selectivity were identified. Depending on the nature of the P(1)(') and P(2)(') substituents, two different binding modes were observed in X-ray co-crystal structures. 相似文献
219.
Imtiyaz Murtaza G. M. Beigha Tanveer Ahmad Shah Amjad Hussain Athar Ali Khan Charanjit Kaur 《Journal of plant biochemistry and biotechnology.》2005,14(2):215-217
Green leafy vegetable extracts of six genotypes of kale (Brassica oleracea acephala) were evaluated for ascorbic acid, carotenoids, total phenolics and antioxidant activity. Ascorbic acid ranged from 142 mg per 100 g in Wappal Hakh to 164 mg per 100 g fr wt in Knol khol. Wild genotypes Wappal and Pumb, had significantly high phenolic content (285 and 227 mg per 100 g fr wt) and possessed highest antioxidant activities (840 and 780 µmol FRAP per g fr wt) than cultivated genotypes. A positive and strong correlation (R2 = 0.807) between total phenolic content and antioxidant activity suggests that kale has enormous potential to enhance the antioxidant potential of our daily food supply. Wild genotypes, Wappal and Pumb can be incorporated into the breeding programmes in order to increase the antioxidant potential of cultivated varieties. 相似文献
220.
Chorvatova Alzbeta Snowdon Richard Hart George Hussain Munir 《Molecular and cellular biochemistry》2004,261(1):217-226
We investigated the effects of pressure overload hypertrophy on inward sodium (I
Na) and calcium currents (I
Ca) in single left ventricular myocytes to determine whether changes in these current systems could account for the observed prolongation of the action potential. Hypertrophy was induced by pressure overload caused by banding of the abdominal aorta. Whole-cell patch clamp experiments were used to measure tetrodotoxin (TTX)-sensitive inward currents. The main findings were that I
Ca density was unchanged whereas I
Na density after stepping from –80 to –30 mV was decreased by 30% (–9.0 ± 1.16 pA pF–1 in control and –6.31 ± 0.67 pA pF–1 in hypertrophy, p < 0.05, n= 6). Steady-state activation/inactivation variables of I
Na, determined by using double-pulse protocols, were similar in control and hypertrophied myocytes, whereas the time course of fast inactivation of I
Na was slowed (p < 0.05) in hypertrophied myocytes. In addition, action potential clamp experiments were carried out in the absence and presence of TTX under conditions where only Ca2+ was likely to enter the cell via TTX-sensitive channels. We show for the first time that a TTX-sensitive inward current was present during the plateau phase of the action potential in hypertrophied but not control myocytes. The observed decrease in I
Na density is likely to abbreviate rather than prolong the action potential. Delayed fast inactivation of Na+ channels was not sustained throughout the voltage pulse and may therefore merely counteract the effect of decreased I
Na density so that net Na+ influx remains unaltered. Changes in the fast I
Na do not therefore appear to contribute to lengthening of the action potential in this model of hypertrophy. However, the presence of a TTX-sensitive current during the plateau could potentially contribute to the prolongation of the action potential in hypertrophied cardiac muscle. (Mol Cell Biochem 261: 217–226, 2004) 相似文献