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41.
Proposed: an international code of ethics for medical genetics   总被引:2,自引:0,他引:2  
Wertz DC, Fletcher JC. Proposed: an international code of ethics for medical genetics.
Clin Genet 1993: 44: 37–43. © Munksgaard, 1993  相似文献   
42.
Summary Sleep length and sleep quality scores were collected on board ships over periods of up to two weeks from 38 watchkeepers working a 4-on/8-off routine and 29 dayworkers. All watchkeepers exhibited fragmented sleeping patterns, which indicated a lack of adaptation of the sleep/wakefulness cycle to the hours of work. There were only slight differences in total sleep length between watchkeepers and dayworkers, however, both groups did not obtain an adequate amount of sleep. Within the watchkeeping crews the 3rd Officers had by far the shortest sleep length. Concerning sleep quality, daytime sleep was generally given the lowest ratings, whereas sleep starting before midnight was on average evaluated as the best, both by watchkeepers and dayworkers. Watchkeeping personnel do not normally have any days off during a voyage so that missed sleep might even amount to a sleep deficit. A solution for this problem could perhaps be a new, stabilized system that allows a single uninterrupted sleep, which is required for full recuperation, to be taken each day.Dedicated to Professor J. Aschoff on the occasion of his 75th birthdayPartly supported by a grant from the Ministry for Technology and Research, Federal Republic of Germany, Project Schiff der Zukunft, Part ET83b  相似文献   
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44.
Xing S  Santerre Jp  Labow RS  Boynton EL 《Biomaterials》2002,23(17):3595-3602
Macrophages and polyethylene (PE) particulate are currently recognized as being the two common denominators in the development of chronic inflammation, periprosthetic osteolysis, and subsequent implant failure. In this study, the effect of PE particulate surface chemistry on mature human monocyte-derived macrophage (MDM) function was investigated. Virgin high-density PE (HDPE: 4-10 microm) and HDPE oxidized by irradiation, thermal and chemical treatment were characterized by FT-IR and suspended in soluble type I collagen, which was subsequently solidified on glass coverslips. Human MDMs, derived from differentiating monocytes on polystyrene for 14 days, were trypsinized and cultured on collagen-particle substrata and collagen controls for 31 days. Analysis of conditioned media collected at 24h incubation showed a significantly higher level of IL-1beta secretion in virgin HDPE over oxidized HDPE or collagen controls, and a significant inhibition of IL-6 secretion in both virgin and oxidized samples. Esterase activity was increased in the medium at a significantly higher level in the virgin HDPE versus controls with the highest activity observed in oxidized HDPE at 31 days. These results illustrate the effect of PE particle surface chemistry (oxidation) on MDM cytokine secretion and esterase activity, and highlight the need to further investigate the potential of PE surface chemistry on modulating MDM function.  相似文献   
45.
There was little difference between the proportion of lesions found by excretion urography in patients with recurrent urinary tract infections referred by general practitioners or hospital staff, or between Horton General Hospital which is a district general hospital, and the United Oxford Hospitals, which is a teaching group. Many patients with urinary tract infections may be saved an unnecessary visit to the hospital consultant if this is first investigated by the general practitioner.

About one fifth of all patients had significant lesions shown by excretory urography which suggests that the investigation is worthwhile in patients with recurrent urinary tract infections.

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46.
Sixty-one 12- to 18-year-olds were randomized to 8-10 sessions of behavior management training (n = 20), problem-solving and communication training (n = 21), or structural family therapy (n = 20). Families were assessed at pre- and posttreatment and 3-month follow-up. All treatments resulted in significant reductions in negative communication, conflicts, and anger during conflicts and improved ratings of school adjustment, reduced internalizing and externalizing symptoms, and decreased maternal depressive symptoms. Most outcomes remained stable between posttreatment and follow-up, and some continued to improve over this time. Despite group improvements, analyses of clinically significant change and clinical recovery within Ss showed that only 5-30% reliably improved from treatment and only 5-20% recovered following treatment. The three treatments did not differ in these rates.  相似文献   
47.
48.
Understanding the regulation of immune responses is central for control of autoimmune and infectious disease. In murine models of autoimmunity and chronic inflammatory disease, potent regulatory T lymphocytes have recently been characterized. Despite an explosion of interest in these cells, their relevance to human disease has been uncertain. In a longitudinal study of malaria sporozoite infection via the natural route, we provide evidence that regulatory T cells have modifying effects on blood-stage infection in vivo in humans. Cells with the characteristics of regulatory T cells are rapidly induced following blood-stage infection and are associated with a burst of TGF-beta production, decreased proinflammatory cytokine production, and decreased antigen-specific immune responses. Both the production of TGF-beta and the presence of CD4+CD25+FOXP3+ regulatory T cells are associated with higher rates of parasite growth in vivo. P. falciparum-mediated induction of regulatory T cells may represent a parasite-specific virulence factor.  相似文献   
49.
Perception of our own bodies is based on integration of visual and tactile inputs, notably by neurons in the brain's parietal lobes. Here we report a behavioural consequence of this integration process. Simply viewing the arm can speed up reactions to an invisible tactile stimulus on the arm. We observed this visual enhancement effect only when a tactile task required spatial computation within a topographic map of the body surface and the judgements made were close to the limits of performance. This effect of viewing the body surface was absent or reversed in tasks that either did not require a spatial computation or in which judgements were well above performance limits. We consider possible mechanisms by which vision may influence tactile processing.  相似文献   
50.
Rhoads CS  Elmore JG  Fletcher S 《The New England journal of medicine》2000,342(26):2002; author reply 2002-2002; author reply 2003
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