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71.

Background:

Cancer fear and fatalism are believed to be higher in ethnic minorities and may contribute to lower engagement with cancer prevention and early detection. We explored the levels of cancer fear and fatalism in six ethnic groups in the United Kingdom and examined the contribution of acculturation and general fatalism.

Methods:

A cross-sectional survey of 720 White British, Caribbean, African, Indian, Pakistani, and Bangladeshi women (120 of each) was conducted. Three items assessed cancer fear and two cancer fatalism. Acculturation was assessed using (self-reported) migration status, ability to speak English, and understanding of health leaflets; general fatalism with a standard measure.

Results:

Relative to White British women, African and Indian women were more fearful of cancer, Bangladeshi women less fearful, and Pakistani and Caribbean women were similar to White British women. Cancer fatalism was higher in all the ethnic minority groups compared with White British women. Less acculturated women were less likely to worry (ORs 0.21–0.45, all P<0.05) or feel particularly afraid (ORs 0.11–0.31, all P<0.05) but more likely to feel uncomfortable about cancer (ORs 1.97–3.03, all P<0.05). Lower acculturation (ORs 4.30–17.27, P<0.05) and general fatalism (OR 2.29, P<0.05) were associated with the belief that cancer is predetermined.

Conclusions:

In general, cancer fear and fatalism are more prevalent among ethnic minority than White British women and even more so in less acculturated ethnic minorities. This may affect their participation in cancer prevention and early detection.  相似文献   
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In this report we describe an open fracture of trapezoid and break in anterior cortex of capitate due to assault in a young adult male. Direct impact force of a sharp object to the first web space caused the above fractures. Open reduction and internal fixation of the trapezoid was carried out using Kirschner wires. Cut extensor tendons, extensor retaniculum, capsule, adductor pollicis muscle, first dorsal interosseous muscle, soft tissue and overlying skin were sutured primarily. Three months after the operation the patient has made a complete recovery. There is no similar case reported in the literature.  相似文献   
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Long-range and local RNA-RNA contacts in viral RNA genomes result in tertiary structures that modulate the function of enhancers, promoters, and silencers during translation, RNA replication, and encapsidation. In the case of flaviviruses, the presence of inverted complementary sequences at the 5' and 3' ends of the genome mediate long-range RNA interactions and RNA cyclization. The circular conformation of flavivirus genomes was demonstrated to be essential for RNA amplification. New ideas about the mechanisms by which circular genomes participate in flavivirus replication have emerged in the last few years. Here, we will describe the latest information about cis-acting elements involved in flavivirus genome cyclization, RNA promoter elements required for viral polymerase recognition, and how these elements together coordinate viral RNA synthesis.  相似文献   
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In positive-stranded viruses, the genomic RNA serves as a template for both translation and RNA replication. Using poliovirus as a model, we examined the interaction between these two processes. We show that the RNA polymerase is unable to replicate RNA templates undergoing translation. We discovered that an RNA structure at the 5′ end of the viral genome, next to the internal ribosomal entry site, carries signals that control both viral translation and RNA synthesis. The interaction of this RNA structure with the cellular factor PCBP up-regulates viral translation, while the binding of the viral protein 3CD represses translation and promotes negative-strand RNA synthesis. We propose that the interaction of 3CD with this RNA structure controls whether the genomic RNA is used for translation or RNA replication.  相似文献   
79.
Obtaining karyotypes from human spermatozoa after microinjection into Syrian golden hamster oocytes is difficult and the hitherto reported results are unsatisfactory. This may be related to the injection and culture technique or to the high susceptibility of the hamster oocytes to undergo parthenogenetic activation or both. Therefore, we investigated the hamster oocyte-human sperm microinjection model using the following two approaches: (i) application of contemporary techniques for injection (touching the sperm tail) and culture (hamster embryo culture medium, HECM-3, 10% CO2) and (ii) omission of Ca2+ from the injection medium. Thus, in the first series of experiments, 252 hamster oocytes were injected with human spermatozoa. Among the 219 (87%) oocytes that survived the injection procedure, the mean percentages of male pronucleus formation [two pronuclei (2PN), two polar bodies (PB)], mitotic metaphase entry and sperm chromosome spreads were 41.4, 27.8 and 18.2% respectively. Analysis of the oocytes which failed to develop the male pronucleus following injection revealed that most of them had developed only the hamster female PN while the sperm nuclei were either intact or swollen (partially decondensed), indicating that failure of oocyte activation was not the likely reason for the failure of male PN formation in these oocytes. In the next series of experiments, sibling oocytes were alternately injected with spermatozoa suspended either in the regular (1.9 mM Ca2+) or Ca2+-free injection medium (experiment set 2, n=278). A significant improvement was noted in the mean percentages of oocytes with 2PN, 2PB, metaphase entry and sperm chromosome spreads in the Ca2+-free group versus the regular group (2PN, 2PB: 51 versus 36.6%, metaphase entry: 36.3 versus 26.9% and sperm chromosome spreads: 28 versus 20.4%; all P < 0.04). Thus, parthenogenetic activation appears to be one of the contributing factors for the failure of male PN formation after heterospecific hamster ICSI. From these experiments it can be concluded that application of the advanced injection and culture techniques and omission of Ca2+ from the injection medium are promising for the routine application of the hamster oocyte microinjection for karyotyping of human spermatozoa with poor fertilizing capacity.   相似文献   
80.
Nuclear adenosine diphosphate-ribosyl (ADP-ribosyl) transferase is a chromatin-bound enzyme catalyzing the transfer of ADP-ribose from NAD+ to chromatin proteins. The physiologic function of this covalent modification of chromatin has not been fully established, but roles in both DNA repair and in differentiation have been proposed. We demonstrate that three specific inhibitors of ADP-ribosyl transferase (5-methylnicotinamide, 3-methoxybenzamide, 3-aminobenzamide) inhibit differentiation of human granulocyte-macrophage progenitor cells to the macrophage lineage. Differentiation to the neutrophil-granulocyte lineage is much less affected. The inhibition of macrophage differentiation seems to relate to the ability of these compounds to inhibit ADP-ribosyl transferase. A structural analogue (3- methoxybenzoic acid), which is not inhibitory for the enzyme, did not inhibit macrophage differentiation. Additional evidence for a role of ADP-ribosyl transferase in the differentiation of granulocyte- macrophage progenitors was obtained from experiments in which enzyme activity levels were measured in permeabilized marrow cells. Marrow cell ADP-ribosyl transferase activity increased after 3-hr stimulation by the differentiation/proliferation stimulus--granulocyte-macrophage colony-stimulating activity (GM-CSA). Unstimulated marrow cells showed low or undetectable levels of enzyme activity.  相似文献   
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