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41.
Posttransplant lymphoproliferative disorder (PTLD) is a serious complication of solid organ transplantation (SOT). Most PTLD cases are associated with Epstein–Barr virus (EBV) infection. The role of antiviral prophylaxis or rituximab therapy for prevention of PTLD in SOT recipients is controversial. In a nationwide cohort, we assessed the incidence, presentation, and outcome of histologically proven PTLD. We included 4765 patients with a follow-up duration of 23 807 person-years (py). Fifty-seven PTLD cases were identified; 39 (68%) were EBV positive (EBV+ PTLD). Incidence rates for EBV+ PTLD at 1, 2, and 3 years posttransplant were 3.51, 2.24, and 1.75/1000 py and 0.44, 0.25, and 0.29/1000 py for EBV− PTLD. We did not find an effect of antiviral prophylaxis on early and late EBV+ PTLD occurrence (early EBV+ PTLD: SHR 0.535 [95% CI 0.199–1.436], p = .264; late EBV+ PTLD: SHR 2.213, [95% CI 0.751–6.521], p = .150). However, none of the patients (0/191) who received a rituximab-containing induction treatment experienced PTLD, but 57 of 4574 patients without rituximab induction developed PTLD. In an adjusted restricted mean survival time model, PTLD-free survival was significantly longer (0.104 years [95% CI 0.077–0.131]) in patients receiving rituximab as induction treatment. This study provides novel data on the association of rituximab induction and reduced risk for PTLD.  相似文献   
42.
Journal of Community Health - Tattoos of formerly gang-involved and incarcerated individuals can negatively impact their ability to reintegrate into society. Laser tattoo removal is essential to...  相似文献   
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44.
Evidence suggests that adult cancer risk of hormonally related tumors may be influenced by the in utero environment, and most speculation on the biological mechanism has focused on the hormonal component. Epidemiological studies investigating the biological nature of pregnancy and maternal factors associated with offspring's cancer risk have relied on maternal hormone measurements. The degree to which maternal hormone levels represent the fetal environment, however, is not widely known. Pregnancy estrogen, androstenedione, testosterone, dehydroepiandrosterone (DHEA), and DHEA-sulfate concentrations were measured in maternal and mixed umbilical cord sera from 86 singleton pregnancies. Spearman correlations between maternal and cord hormone levels generally ranged between 0.2 and 0.3. The correlation was 0.26 for estriol, the estrogen of highest concentration in pregnancy, and 0.27 for estradiol, the most biologically active estrogen. The correlations between mother and offspring for the estrogens and DHEA appeared similar for males and females, whereas there was a suggestion that the maternal-umbilical cord correlations for other androgens varied in magnitude by fetal sex, and all correlations appeared higher in pregnancies lasting <38 weeks compared with longer gestational lengths, although these stratified findings may have been attributable to chance. These data show a moderate degree of correlation in hormone concentrations between the maternal and fetal circulation. Studies using maternal hormone concentrations as a proxy for the fetal environment should consider the misclassification resulting with the use of this marker.  相似文献   
45.
A systematic review of radiation therapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately (Acta Oncol 2003; 42: 357-365). This synthesis of the literature on radiation therapy for cervical cancer is based on data from 1 meta-analysis and 34 randomized trials. In total, 35 scientific articles are included, involving 7 952 patients. The results were compared with those of a similar overview from 1996 including 34 024 patients. The conclusions reached can be summarized in these points: There are limited scientific data supporting that postoperative pelvic radiotherapy improves disease-free survival in early cervical cancer. No firm conclusion can be drawn.There is moderate scientific evidence that external beam radiotherapy combined with brachytherapy gives a similar disease-free and overall survival rate as radical hysterectomy in early cervical cancer.There is strong scientific evidence that concomitant radiochemotherapy improves disease-free and overall survival compared to radiotherapy alone in early cervical cancer.The NCI has recently published an announcement stating that cisplantin-based chemotherapy should be used concomitantly with radiotherapy in cervical cancer. No solid documentation for this statement can be found concerning locally advanced stages (>IIB).There is a strong scientific evidence that cisplatin-based chemotherapy given concomitantly with radiotherapy is superior to concomitant chemotherapy with hydroxyurea.There is no scientific evidence to show that neoadjuvant chemotherapy followed by radiotherapy improves disease-free or overall survival compared to radiotherapy alone in patients with localized cervical cancer.There is moderate scientific evidence that high-dose-rate brachytherapy gives the same local control rate as low-dose-rate brachytherapy but with fewer rectal complications.  相似文献   
46.
A systematic assessment of radiotherapy for cancer was conducted by The Swedish Council on Technology Assessment in Health Care (SBU) and published in 1996. The assessment reviewed the scientific literature up to 1993 on the use of radiotherapy in the treatment of solid tumours, and estimated the costs associated with radiotherapy. It also described the current practise of radiotherapy in Sweden 1992 and compared practise with scientific knowledge. The SBU has now conducted a follow-up study on radiotherapy for cancer, including a review of the scientific literature from 1994 and a prospective survey of radiotherapy practise in Sweden 2001. The following conclusions were drawn: The role of radiotherapy as an important form of treatment for cancer with both curative and palliative intent has been further confirmed.The use of radiotherapy in Sweden has increased and is now at the internationally recommended level.Radiotherapy in Sweden is mostly given in accordance with the scientific evidence but may still be underutilized in certain situations.The resources for radiotherapy are being utilized more efficiently.The costs of radiotherapy are still 5% of the total cost of cancer care, while the cost of an individual treatment (fraction) has decreased.The need for radiotherapy capacity will increase. In addition, half of the treatment equipment will have to be replaced in the next few years.  相似文献   
47.
The aim of this study was to use a new system of realistic voxel phantoms, based on computed tomography scanning of humans, to assess its ability to specify the internal dosimetry of selected human examples in comparison with the well-established MIRD system of mathematical anthropomorphic phantoms. Differences in specific absorbed fractions between the two systems were inferred by using organ dose estimates as the end point for comparison. A "family" of voxel phantoms, comprising an 8-week-old baby, a 7-year-old child and a 38-year-old adult, was used and a close match to these was made by interpolating between organ doses estimated for pairs of the series of six MIRD phantoms. Using both systems, doses were calculated for up to 22 organs for four radiopharmaceuticals with widely differing biodistribution and emission characteristics (technetium-99m pertechnetate, administered without thyroid blocking; iodine-123 iodide; indium-111 antimyosin; oxygen-15 water). Organ dose estimates under the MIRD system were derived using the software MIRDOSE 3, which incorporates specific absorbed fraction (SAF) values for the MIRD phantom series. The voxel system uses software based on the same dose calculation formula in conjunction with SAF values determined by Monte Carlo analysis at the GSF of the three voxel phantoms. Effective doses were also compared. Substantial differences in organ weights were observed between the two systems, 18% differing by more than a factor of 2. Out of a total of 238 organ dose comparisons, 5% differed by more than a factor of 2 between the systems; these included some doses to walls of the GI tract, a significant result in relation to their high tissue weighting factors. Some of the largest differences in dose were associated with organs of lower significance in terms of radiosensitivity (e.g. thymus). In this small series, voxel organ doses tended to exceed MIRD values, on average, and a 10% difference was significant when all 238 organ doses were considered as a single group. In 12 comparisons of effective dose, the mean voxel to MIRD ratio was 1.07 (range 0.72-1.32). It was shown for the majority of cases that, whereas some large differences in SAF values exist, differences in source organ and effective dose values between the MIRD and voxel methods were largely accounted for by the respective organ mass differences. The reasons for various organ dose differences with the selected radiopharmaceuticals are discussed. Taking biological variation into account, there is reasonable agreement between the two methods but some significant differences exist that warrant further investigation. More extensive comparisons involving a wide variety of voxel phantoms are required to establish whether realistic voxel phantoms should eventually replace the MIRD system.  相似文献   
48.
目的:为临床外科寻找简便易行有效的预防腹腔术后粘连的新方法和药物:方法:用白及、黄芪等多味中药制成抗粘灵气雾剂,通过对60只家免盲肠部分切除制造实验动物模型,并对其创面进行活体药物喷涂。结果:抗粘灵气雾剂预防腹腔术后粘连效果良好,总有效率86.67%,与对照组比较,有非常显著差异(P〈0.01)。结论:抗粘灵气雾剂预防腹腔术后粘连有效,且方法简便易行,从而可为临床外科领域提供高效。价廉的木申抗粘连药物。  相似文献   
49.
50.
Helicobacter pylori infection of the human stomach is the most important risk factor for development of gastric cancer. Whereas persistent viral infection leads to a number of cancers, H. pylori was the first bacteria linked to a human cancer. The exact mechanisms that lead to cancer induction are not clear, but study of the bacterial factors important for colonization and the host responses to the infection are starting to yield important clues.  相似文献   
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