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81.
Background: We performed a phase I study of a novel system of complete hepatic venous isolation and extracorporeal chemofiltration in patients with unresectable hepatocellular carcinoma (HCC) to determine (a) whether systemic exposure to doxorubicin could be limited after high-dose hepatic arterial infusion (HAI), and (b) the hepatic maximum tolerated dose (MTD) of doxorubicin. Methods: Ten patients with biopsy-proven HCC were treated with 20-min HAI of doxorubicin (17 total treatments). Two patients were treated with doxorubicin 60 mg/m2, three patients were treated at 90 mg/m2, and five patients received 120 mg/m2. A newly developed dual-balloon vena cava catheter was advanced from the femoral vein, and the balloons were inflated to isolate and capture total hepatic venous outflow. The hepatic venous blood was pumped through extracorporeal carbon chemofilters before return of the blood to the systemic circulation. Results: Peak systemic doxorubicin levels were an average 85.6% lower than were peak prefilter levels (p<0.01). Because all catheters were placed percutaneously and because the chemofiltration markedly limited systemic chemotherapy exposure, patients were discharged 1 day after 16 of the 17 treatments. The hepatic and systemic MTD of doxorubicin in this treatment protocol was 120 mg/m2. Conclusions: This novel system of complete hepatic venous isolation and chemofiltration limits systemic chemotherapy toxicity and will allow use of higher doses of chemotherapeutic agents to treat HCC. The results of this study were presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.  相似文献   
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The 8th Conference of the British Psychosocial Oncology Group was held in London on 9–10 December 1991 and attracted over 120 participants. The conference was extended from its usual one day format to one and a half days, to allow more time for both a formal and informal exchange of ideas. Eight invited speakers participated, but proferred papers and posters remained an important focus of the meeting. This is the largest annual conference in Britain for professionals working in psychosocial oncology and an important forum for the presentation of research. As in previous years, the conference attracted a number of newcomers, indicating the continued expansion of this field of research. A number of topical issues were presented in keynote papers by invited speakers. New work in cancer prevention and the associated areas of counselling families at risk and ethical issues, formed one symposium. Communication skills and relevant training needs in paediatric and adult oncology were an important theme of the conference and intervention studies formed the third main topic.  相似文献   
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The goal was to determine the age-related changes in accommodative movements of the lens and ciliary body in rhesus monkeys. Varying levels of accommodation were stimulated via the Edinger-Westphal (E-W) nucleus in 26 rhesus monkeys, aged 6–27 years, and the refractive changes were measured by coincidence refractometry. Centripetal ciliary process (CP) and lens movements were measured by computerized image analysis of goniovideographic images. Ultrasound biomicroscopy (UBM) at 50 MHz was used to visualize and measure accommodative forward movements of the ciliary body in relation to age, accommodative amplitude, and centripetal CP and lens movements. At ~3 diopters of accommodation, the amount of centripetal lens movement required did not significantly change with age (p = 0.10; n = 18 monkeys); however, the amount of centripetal CP movement required significantly increased with age (p = 0.01; n = 18 monkeys), while the amount of forward ciliary body movement significantly decreased with age (p = 0.007; n = 11 monkeys). In the middle-aged animals (12–16.5 years), a greater amount of centripetal CP movement was required to induce a given level of lens movement and thereby a given level of accommodation (p = 0.01), compared to the young animals (6–10 yrs). Collectively, the data suggests that, with age, the accommodative system may be attempting to compensate for the loss of forward ciliary body movement by increasing the amount of centripetal CP movement. This, in turn, would allow enough zonular relaxation to achieve the magnitude of centripetal lens movement necessary for a given amplitude of accommodation.  相似文献   
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OBJECTIVE: To evaluate the effectiveness of a new method of using Independent Component Analysis (ICA) and k-means clustering to increase the signal-to-noise ratio of Event-Related Potential (ERP) measurements while permitting standard statistical comparisons to be made despite the inter-subject variations characteristic of ICA. METHODS: Per-subject ICA results were used to create a channel pool, with unequal weights, that could be applied consistently across subjects. Signals derived from this and other pooling schemes, and from unpooled electrodes, were subjected to identical statistical analysis of the N170 own-face effect in a Joe/No Joe face recognition paradigm wherein participants monitored for a target face (Joe) presented amongst other unfamiliar faces and their own face. Results between the Joe, unfamiliar face and own face conditions were compared using Cohen's d statistic (square root of signal-to-noise ratio) to measure effect size. RESULTS: When the own-face condition was compared to the Joe and unfamiliar-face conditions, the channel map method increased effect size by a factor ranging from 1.2 to 2.2. These results stand in contrast to previous findings, where conventional pooling schemes failed to reveal an N170 effect to the own-face stimulus (Tanaka JW, Curran T, Porterfield A, Collins D. The activation of pre-existing and acquired face representations: the N250 ERP as an index of face familiarity. J Cogn Neurosci 2006;18:1488-97). Consistent with conventional pooling schemes, the channel map approach showed no reliable differences between the Joe and Unfamiliar face conditions, yielding a decrease in effect size ranging from 0.13 to 0.75. CONCLUSIONS: By increasing the signal-to-noise ratio in the measured waveforms, the channel pool method demonstrated an enhanced sensitivity to the neurophysiological response to own-face relative to other faces. SIGNIFICANCE: By overcoming the characteristic inter-subject variations of ICA, this work allows classic ERP analysis methods to exploit the improved signal-to-noise ratio obtainable with ICA.  相似文献   
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Fracture of the hip is frequently a catastrophic event in the elderly, often resulting in death within a year and of the survivors, few regain pre-fracture quality of life. Although less appreciated, fractures of the spine result in significant morbidity and are also associated with increased mortality compared with individuals without a fracture. In recent years there has been an explosion in the development of new drugs for the treatment of osteoporosis. Recombinant human parathyroid hormone (1–34) (20 μg/day) is a recent addition to this armamentarium with a novel mechanism of action, which was approved by the US FDA for the treatment of post-menopausal osteoporosis and male osteoporosis secondary to hypogonadism in November 2002. It is the first osteoporosis treatment that leads to the formation of new bone with architecture similar to normal bone. Intense efforts have been made to understand the effect of teriparatide on antiresorptive therapy and vice versa. Although these relationships are not completely understood, the results of recent studies allow clinicians to begin to optimize therapeutic gains in bone mineral density and improve anti-fracture efficacy.  相似文献   
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