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1.
We present a patient who developed a painful third nerve galsy two days after angiography had demonstrated a large aneurysm on the P1 segment of the left posterior cerebral artery. CT at this stage demonstrated extensive thrombus within the previously uncomplicated aneurysm. The haemodynamics of this aneurysm resulted in incomplete clearance of contrast medium from its fundus and we posit that this may have promoted thrombus formation. Six months later the aneurysm was shown angiographically to be completely occluded. 相似文献
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This study examines the need for a comprehensive patient educationprogram that emphasizes self-help for adults living with HIV/AIDS.Data were collected using a self-administered, written questionnaire.Participants were recruited from agencies in northern California.This study revealed that 59 of 70 respondents were relativelysatisfied with the services, including patient education, availablein their community. Of the 70 respondents, 69 felt there wasa need for a comprehensive patient education program. The study'sfindings illustrate both distinct differences and commonaltiesbetween the experiences, perceived needs and priorities of maleand female respondents. These findings will help HIV/AIDS serviceagencies re-structure their health education programs and assistin patient education program development. Future research inthis area needs to address the perceived needs and prioritiesof different subgroups living with HIV/AIDS. 相似文献
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A silencing pathway to induce H3-K9 and H4-K20 trimethylation at constitutive heterochromatin 总被引:31,自引:1,他引:31 下载免费PDF全文
Schotta G Lachner M Sarma K Ebert A Sengupta R Reuter G Reinberg D Jenuwein T 《Genes & development》2004,18(11):1251-1262
Histone lysine methylation is a central modification to mark functionally distinct chromatin regions. In particular, H3-K9 trimethylation has emerged as a hallmark of pericentric heterochromatin in mammals. Here we show that H4-K20 trimethylation is also focally enriched at pericentric heterochromatin. Intriguingly, H3-K9 trimethylation by the Suv39h HMTases is required for the induction of H4-K20 trimethylation, although the H4 Lys 20 position is not an intrinsic substrate for these enzymes. By using a candidate approach, we identified Suv4-20h1 and Suv4-20h2 as two novel SET domain HMTases that localize to pericentric heterochromatin and specifically act as nucleosomal H4-K20 trimethylating enzymes. Interaction of the Suv4-20h enzymes with HP1 isoforms suggests a sequential mechanism to establish H3-K9 and H4-K20 trimethylation at pericentric heterochromatin. Heterochromatic H4-K20 trimethylation is evolutionarily conserved, and in Drosophila, the Suv4-20 homolog is a novel PEV modifier to regulate position-effect variegation. Together, our data indicate a function for H4-K20 trimethylation in gene silencing and further suggest H3-K9 and H4-K20 trimethylation as important components of a repressive pathway that can index pericentric heterochromatin. 相似文献
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Preimplantation embryo morphology following early luteal phase anti-nidatory treatment with mifepristone (RU486) in the rhesus monkey 总被引:6,自引:0,他引:6
Ghosh D Lalitkumar PG Wong VJ Hendrickx AG Sengupta J 《Human reproduction (Oxford, England)》2000,15(1):180-188
The ultrastructural characteristics of peri-implantation stage embryos recovered on day 6 after ovulation from rhesus monkeys with or without mifepristone (RU486) treatment during the early luteal phase were examined in the present study. Monkeys were randomly allocated to two groups; group 1 animals were injected s.c. with 2 ml vehicle (1:4, benzyl benzoate: olive oil, v/v, n = 21) and group 2 animals received a single dose of mifepristone (2 mg/kg body weight, w/v, n = 30) in the same volume of vehicle on day 2 after ovulation in mated cycles. On day 6 after ovulation, female monkeys of both groups were laparotomized and their reproductive tracts were flushed to retrieve preimplantation stage embryos. Embryos that showed frank degeneration or desynchrony on gross microscopical examination were not included in the present study. Preimplantation embryo growth on day 6 after ovulation was significantly (P < 0.05) affected in the morula-blastocyst transition stage in mifepristone-treated monkeys compared with that in the control group of monkeys. Ultrastructurally, administration of mifepristone on day 2 after ovulation depressed preimplantation stage embryo development, characterized by loss of cell polarity, lack of mitochondrial maturity, and lack of differentiation in trophoblast cells. Furthermore, preimplantation embryos from mifepristone-treated animals displayed a higher occurrence of inter-blastomere space, intra-cytoplasmic vacuoles, myelinoid bodies, accumulation of lipid droplets, lysosomes, lipofuscins, autophagosomes and multivesicular bodies. Collectively, it appears that the developmental potential of preimplantation embryos was significantly compromised in mifepristone-treated cycles. 相似文献
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Benzoxazole-2-thiol ( 1 )/dibenzoyl peroxide (Bz2O2) was used as photoinitiator for the polymerization of methyl methacrylate (MMA) in bulk and in solution. The study of initiator decomposition was conducted spectrophotometrically. Kinetic studies of the photopolymerization indicated the formation of a complex between 1 and Bz2O2 in the stoichiometric ratio 2:1. The initiation is believed to occur via in situ formation of bis(benzoxazol-2-yl) disulfide in the presence of light. 相似文献
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Immunohistological localisation of vascular endothelial growth factor in human endometrium. 总被引:2,自引:0,他引:2
B Naresh J Sengupta V Bhargava G Kinra J Hu D Ghosh 《Indian journal of physiology and pharmacology》1999,43(2):165-170
Several polypeptide growth factors regulate epithelial and stromal development in endometrium under the influence of estrogen and progesterone, and thereby regulate growth and differentiation of endometrium during menstrual cycle. However, little is known about the angiogenic growth factors that may affect endometrial vasculature throughout each menstrual cycle. Vascular endothelial growth factor (VEGF) is suggestively an important angiogenic growth factor in the female reproductive tract. The aim of the present study was to immunolocalize and assess semi-quantitatively VEGF immunostaining in cells of proliferative phase (n = 3), secretory phase (n = 6) and hyperplastic (n = 6) human endometrial samples. VEGF concentrations were significantly higher in glandular (P < 0.001) and stromal (P < 0.01) compartments of proliferative stage endometrium compared with those in secretory stage and hyperplastic endometrial samples, with no difference in the scores for glandular and stromal compartments between secretory stage and hyperplastic endometrial samples. Generally, glandular expression of VEGF was higher as compared to stromal compartment. Thus, it appears that endometrial VEGF expression and concentration are enhanced by estrogen, and may be correlated with neovascularization and increased vascular permeability during late proliferative period. Additionally, there was no enhancement in VEGF expression in hyperplastic glands, suggesting that regulation of glandular growth and that of angiogenesis in human endometrium operate through different mechanisms. 相似文献