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91.
Radiation exposure of the families of outpatients treated with radioiodine (iodine-131) for hyperthyroidism. 总被引:5,自引:0,他引:5
S F Barrington M J O'Doherty A G Kettle W H Thomson P J Mountford D N Burrell R J Farrell S Batchelor P Seed L K Harding 《European journal of nuclear medicine》1999,26(7):686-692
Patients who receive radioiodine (iodine-131) treatment for hyperthyroidism (195-800 MBq) emit radiation and represent a potential hazard to other individuals. Critical groups amongst the public are fellow travellers on the patient's journey home from hospital and members of the patient's family, particularly young children. The dose which members of the public are allowed to receive as a result of a patient's treatment has been reduced in Europe following recently revised recommendations from ICRP. The annual public dose limit is 1 mSv, though adult members of the patient's family are allowed to receive higher doses, with the proviso that a limit of 5 mSv should not be exceeded over 5 years. Unless the doses received during out-patient administration of radioiodine can be demonstrated to comply with these new limits, hospitalisation of patients will be necessary. The radiation doses received by family members (35 adults and 87 children) of patients treated with radioiodine at five UK hospitals were measured using thermoluminescent dosimeters mounted in wrist bands. Families were given advice (according to current practice) from their treatment centre about limiting close contact with the patient for a period of time after treatment. Doses measured over 3-6 weeks were adjusted to give an estimate of values which might have been expected if the dosimeters had been worn indefinitely. Thirty-five passengers accompanying patients home after treatment also recorded the dose received during the journey using electronic (digital) personal dosimeters. For the "adjusted" doses to infinity, 97% of adults complied with a 5-mSv dose limit (range:0.2-5.8 mSv) and 89% of children with a 1-mSv limit (range: 0.2-7.2 mSv). However 6 of 17 children aged 3 years or less had an adjusted dose which exceeded this 1 mSv limit. The dose received by adults during travel was small in comparison with the total dose received. The median travel dose was 0.03 mSv for 1 h travel (range: 2 microSv-0.52 mSv for 1 h of travel time). These data suggest that hyperthyroid patients can continue to be treated with radioiodine on an out-patient basis, if given appropriate radiation protection advice. However, particular consideration needs to be given to children aged 3 years or younger. Admission to hospital is not warranted on radiation protection grounds. 相似文献
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Kubota T Thomson A Clouston AD Nakazawa Y Steadman C Kerlin P Shimada H Balderson GA Lynch SV Strong RW 《Journal of Hepato-Biliary-Pancreatic Surgery》1999,6(4):377-381
Whether primary sclerosing cholangitis (PSC) occurs after orthotopic liver transplantation is controversial, largely because
the pre-transplant diagnosis of PSC is based on nonspecific radiological and histological findings. We reviewed clinical,
radiological, and histological records of 53 patients who underwent liver transplantation for PSC between 1985 and 1998. Three
patients with patent hepatic arteries and no evidence of chronic rejection had radiological and histological findings that
may have been due to recurrent PSC. Bile duct stricturing in these patients proved permanent and progressive and affected
both the quality of life and graft survival. The first patient, who is 110 months after transplantation, has had repeated
episodes of cholangitis for the last year. The second patient underwent excision of a strictured hepatic duct 45 months after
transplantation and was ultimately retransplanted 95 months after initial transplantation. The third patient underwent left
hemihepatectomy of an atrophied lobe 50 months after transplantation. Although the patient population assessed in this study
is limited, putative recurrent PSC in the allografts has led either to graft loss or to clinically significant hepatobiliary
complications of the graft.
Received for publication on March 8, 1999; accepted on April 30, 1999 相似文献
94.
BACKGROUND: We previously reported the association among donor leukocyte chimerism, apoptosis of presumedly IL-2-deficient graft-infiltrating host cells, and the spontaneous donor-specific tolerance induced by liver but not heart allografts in mice. Survival of the rejection-prone heart allografts in the same strain combination is modestly prolonged by the pretransplant infusion of immature, costimulatory molecule-(CM) deficient donor dendritic cells (DC), an effect that is markedly potentiated by concomitant CM blockade with anti-CD40L (CD154) monoclonal antibody (mAb). We investigated whether the long survival of the heart allografts in the pretreated mice was associated with donor leukocyte chimerism and apoptosis of graft-infiltrating cells, if these end points were similar to those in the spontaneously tolerant liver transplant model, and whether the pretreatment effect was dependent on sustained inhibition of CM expression of the infused immature donor DC. In addition, apoptosis was assessed in the host spleen and lymph nodes, a critical determination not reported in previous studies of either spontaneous or "treatment-aided" organ tolerance models. METHODS: Seven days before transplantation of hearts from B10 (H-2b) donors, 2x10(6) donor-derived immature DC were infused i.v. into C3H (H-2k) recipient mice with or without a concomitant i.p. injection of anti-CD40L mAb. Donor cells were detected posttransplantation by immunohistochemical staining for major histocompatibility complex class II (I-Ab) in the cells of recipient lymphoid tissue. CM expression was determined by two-color labeling. Host responses to donor alloantigen were quantified by mixed leukocyte reaction, and cytotoxic T lymphocyte (CTL) assays. Apoptotic death in graft-infiltrating cells and in areas of T-dependent lymphoid tissue was visualized by terminal deoxynucleotidyltransferase-catalyzed dUTP-digoxigenin nick-end labeling and quantitative spectrofluorometry. Interleukin-2 production and localization were estimated by immunohistochemistry. RESULTS: Compared with control heart transplantation or heart transplantation after only DC administration, concomitant pretreatment with immature donor DC and anti-CD40L mAb caused sustained elevation of donor (I-Ab+) cells (microchimerism) in the spleen including T cell areas. More than 80% of the I-Ab+ cells in combined treatment animals also were CD86+, reflecting failure of the mAb to inhibit CD40/ CD80/CD86 up-regulation on immature DC in vitro after their interaction with host T cells. Donor-specific CTL activity in graft-infiltrating cells and spleen cell populations of these animals was present on day 8, but decreased strikingly to normal control levels by day 14. The decrease was associated with enhanced apoptosis of graft-infiltrating cells and of cells in the spleen where interleukin-2 production was inhibited. The highest levels of splenic microchimerism were found in mice with long surviving grafts (>100 days). In contrast, CTL activity was persistently elevated in control heart graft recipients with comparatively low levels of apoptotic activity and high levels of interleukin-2. CONCLUSION: The donor-specific acceptance of rejection-prone heart allografts by recipients pretreated with immature donor DC and anti-CD40L mAb is not dependent on sustained inhibition of donor DC CM (CD86) expression. Instead, the pretreatment facilitates a tolerogenic cascade similar to that in spontaneously tolerant liver recipients that involves: (1) chimerism-driven immune activation, succeeded by deletion of host immune responder cells by apoptosis in the spleen and allograft that is linked to interleukin-2 deficiency in both locations and (2) persistence of comparatively large numbers of donor-derived leukocytes. These tolerogenic mechanisms are thought to be generic, explaining the tolerance induced by allografts spontaneously, or with the aid of various kinds of immunosuppression. 相似文献
95.
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98.
Although it is well known that B-vitamin deficiencies directly affecting the brain are common in alcohol misuse, no concise guidelines on the use of vitamin supplements in alcohol misusers currently exist in the UK. The purpose of this study was to assess current practice and opinion among UK physicians. Questionnaires were completed by a total of 427 physicians comprising Accident and Emergency (A&E) specialists and psychiatrists, with a response rate of 25%. The main findings were that vitamin deficiency was perceived as being uncommon amongst alcohol misusers (<25%) and there was no consensus as to which B vitamins are beneficial in treatment or the best method of administration of B-vitamin supplementation. The majority of psychiatrists favoured oral administration for prophylaxis against the Wernicke-Korsakoff syndrome in chronic alcohol misusers and parenteral therapy in patients with signs of Wernicke-Korsakoff syndrome. Whilst only just over half the A&E specialists expressed a preference, most favoured parenteral therapy in both cases. Most respondents did not currently have a unit policy/protocol on the management of vitamin supplementation in chronic alcohol misusers. Overall, the findings suggest that there is wide variation in current practice and highlight the need for guidelines in this area. 相似文献
99.
Models of commissioning health services in the British National Health Service: a literature review.
The commissioning of health services is an under-researched area and yet it is critical to the way services meet health needs and to the quality of care. Recent emphasis in the United Kingdom and elsewhere has been on a 'primary care led National Health Service', particularly on locality commissioning through primary care groups. However, there are other models of commissioning using 'programmes of care' (focused on diseases or patient groups rather than geography) which may offer greater benefits. There is little research comparing the benefits and costs of these models, and most are not even clearly enough described to be replicated. There will always be a political dimension to models of commissioning, dependent, for example, on the balance of power in the decision-making process. None the less, a broader knowledge of possible models and a willingness to evaluate rigorously are needed if commissioning of health services is to result in better patient care. 相似文献
100.
Wright CD Havill AM Middleton SC Kashem MA Dripps DJ Abraham WM Thomson DS Burgess LE 《Biochemical pharmacology》1999,58(12):1989-1996
Emerging evidence suggests that mast cell tryptase is a therapeutic target for the treatment of asthma. The effects of this serine protease are associated with both pathophysiologic pulmonary responses and pathologic changes of the asthmatic airway. In this study, the tryptase inhibitor 1,5-bis-[4-[(3-carbamimidoyl-benzenesulfonylamino)-methyl]-p henoxy]-pentane (AMG-126737) was evaluated for its pharmacologic effects against allergen-induced airway responses. AMG-126737 is a potent inhibitor of human lung mast cell tryptase (Ki = 90 nM), with greater than 10- to 200-fold selectivity versus other serine proteases. Intratracheal administration of AMG-126737 inhibited the development of airway hyperresponsiveness in allergen-challenged guinea pigs with an ED50 of 0.015 mg/kg. In addition, the compound exhibited oral activity in the guinea pig model. The in vivo activity of AMG-126737 was confirmed in a sheep model of allergen-induced airway responses, where the compound inhibited early and late phase bronchoconstriction responses and the development of airway hyperresponsiveness. These results support the proposed role of tryptase in the pathology of asthma and suggest that AMG-126737 has potential therapeutic utility in this pulmonary disorder. 相似文献