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目的:明确集中的电话干预能否降低慢性心衰门诊患者死亡或因心衰加重而住院的发生率。设计:多中心、随机对照试验。地点:阿根廷的51个中心(包括公立、私立的医院及流动设施)。参与者:1518例患有稳定的慢性心衰且已接受最佳药物治疗方案治疗的门诊患者,由心脏科主治医师分层后随机分为电话干预组和常规治疗组。干预:在常规治疗的基础上,由一个中心通过护士频繁的电话随访对患者进行教育、辅导和监督。主要观察指标:全因死亡或由于心衰加重而住院。结果:99.5%的患者完成了全部随访。常规治疗组758例患者中由于心衰加重而住院或死亡的比例(235…  相似文献   
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We have previously demonstrated in a rat model that the lumbar intrathecal injection of 0.02 ml 6.3% magnesium sulphate, a concentration iso-osmolar with rat plasma, produces a state of spinal anaesthesia and general sedation which reversed completely after 6 h, without evidence of neurotoxicity, immediately or during the week thereafter. Using the same model and five groups of six animals in each, we administered the same volume and concentration of magnesium sulphate and compared its clinical effects with those of 0.02 ml 12.6% magnesium sulphate, 0.02 ml 2% lignocaine and 0.02 ml 0.9% sodium chloride solution, given as a series of 15 injections on alternate days for a period of 1 month. The animals were then killed and their spinal cords and meninges examined histologically. No significant differences were noted in the times of onset, durations of sensory and motor blockade and the times to full recovery throughout the entire period of 1 month's observation in the animals receiving intrathecal 6.3% magnesium sulphate. In the group receiving 12.6% magnesium sulphate, the time of onset of sensory and motor blockade was shorter and the duration of both parameters was significantly longer than in the former group. Full clinical recovery and resumption of normal eating and drinking took place in both groups throughout the entire series of 15 successive intrathecal injections. Identical, mild, uniform histopathological changes in the spinal cord were seen in all the five groups, including the group in which only the intrathecal catheter was implanted. The complete recovery and benign consequences of repeated intrathecal injections of iso-osmolar magnesium sulphate in a rat model indicate a lack of neurotoxicity and provide an impetus for further trials in larger animal species, before initial clinical trials of this substance, given intrathecally, in humans.  相似文献   
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It is a common algorithm for hand surgeons to diagnose and treat persistent post-traumatic wrist pain as complex regional pain syndrome (CRPS). Although it works for many patients, some conditions that affect the wrist don’t fall in this category and worsen with this treatment practice. We present a single-handed patient who had had a non-displaced distal radius fracture and was treated as CRPS for the next three months. He was eventually diagnosed with late tuberculous tenosynovitis of the wrist and a total wrist arthrodesis was performed. We believe that Mycobacterium tuberculosis infection should be in the differential diagnosis of persistent post-traumatic joint pain. This is especially important as Mycobacterium infections are becoming more common due to an increase in patients with chronic immunosuppression and definitive diagnosis and treatment of tuberculous tenosynovitis needs a high index of clinical suspicion.  相似文献   
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OBJECTIVE: The aim of the study was to examine the dose enhancement from scattered radiation at bone-dental implant interfaces during simulated head and neck radiotherapy. STUDY DESIGN: Four cylindrical titanium dental implants with 3 different sizes and lengths were implanted into a human mandible in 4 different positions. Ionization measurements for 6 MV X, 25 MV X, and Co-60 gamma rays were done. Thermoluminescent dosimeter (TLD 100 ) chips were used to measure radiation dose enhancement due to the scattered electrons from titanium and electronic disequilibrium at the tissue-metal interface. RESULTS: The results showed that for Co-60, there is a 21% maximum increase in dose to alveolar mandibular bone at the close proximity to the titanium. For 6-MV x-rays the dose enhancement increase was almost the same or slightly lower than for Co-60, while for 25-MV high-energy x-rays, dose enhancement was lower than that of others. This increase in dose enhancement fell off rapidly and became insignificant at 2 mm from the interface. CONCLUSION: Total dose that may lead to osteoradionecrosis risk of the mandible is slightly but not significantly affected by the scattered dose of the dental implants of lower jaw in the radiation field exposed to 3 different radiation beams.  相似文献   
7.
Bacteria isolated from 108 intra-uterine contraceptive devices (IUCD) removed from patients with pelvic inflammatory disease (PID), haemorrhage, pregnancy and from asymptomatic women, and from the genital tracts of 66 healthy controls not wearing an IUCD, were studied. No significant differences were found in the types of micro-organisms or isolation rates from IUCDs removed from women in the various clinical groups. The isolation rate of anaerobic bacteria from IUCDs removed from asymptomatic wearers was significantly lower than that from controls, with the exception of the isolation rate of actinomyces which was significantly higher in IUCD wearers and A. israelii was recovered only from IUCDs. The isolation rates of the different bacterial species varied with the duration of the device in utero. The presence of a copper IUCD altered the bacterial flora of the female genital tract. The insertion of such a device and the ecological changes that follow play a crucial role in the development of PID.  相似文献   
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PURPOSE: To assess dose rate effect on cataractogenesis in allogeneic or autologous bone marrow transplanted patients conditioned with fractionated total-body irradiation (FTBI). MATERIALS AND METHODS: Between 1987 and 2001, a total of 105 patients have received TBI conditioning for Bone Marrow Transplantation (BMT) for hematological malignancies at Gulhane Military Medical School. 12 Gy FTBI was applied in 6 fractions over 3 consecutive days with a Co60 teletherapy machine. 46 patients who have survived and were followed up after more than one year were evaluated for cataractogenesis in relation to dose rate. Conditioning therapy included only cyclophosphamide (60 mg/kg/day for two days) + TBI with no steroid and veno-occlusive disease prophylaxis. RESULTS: The median follow-up is 32 months. Posterior subcapsular cataract developed in 5 eyes of three patients out of 46 patients. The 5-year and 10-year estimated cataract incidence in the high-dose rate (> 0.04 Gy/min) group was 29% and 43% respectively while no cataracts occurred in the low-dose rate (< or = 0.04 Gy/min) group. Cataract development in the high-dose rate group versus low-dose rate group was statistically significant (p < 0.039). CONCLUSION: Cataract is a late side effect of TBI. Low-dose rate fractionated TBI is a reliable conditioning program in BMT with effective lens sparing to avoid cataractogenesis.  相似文献   
10.
In most tissues, various cell membrane ion transporting systems are not fully developed and/or maximally active at the prenatal and early postnatal stage. Their progressive development and expression are a function of growth and maturity. We performed a multiple time-point study, in order to investigate the ability of a variety of tissues to maintain appropriate Ca++ and Mg++ homeostasis at different stages of postnatal development. Total intracellular Ca++ in one-week-old rat liver, brain and spinal cord tissues was significantly elevated, compared to mature animals. It increased further through the first three weeks of gestation. Intracellular Ca++ gradually and significantly declined in adult and mature animal groups. Alterations in total intracellular Mg++ of the same tissue samples, although not so profound, paralleled changes in total intracellular Ca++. We conclude that a developmental switch in intracellular Ca++ and Mg++ homeostasis occurs one to three weeks following birth. It might be related to the incomplete development of Ca++ and Mg++ transmembrane transporting systems, previously reported as being only partially expressed at the early postnatal stage. These developmental alterations in total intracellular Ca++ and Mg++ content might serve as a regulatory mechanism, adjusting cell activities to the physiological requirements of the growing and maturing animal.  相似文献   
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