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BACKGROUND AND PURPOSE: The late morbidity of a randomized study was analyzed after a follow up of 2 years. The difference in intestinal morbidity was analyzed as a function of the treatment arm and dose volume parameters. The correlation with acute toxicity and (pre-existing) bowel complaints was investigated. PATIENTS AND METHODS: 266 T1-4N0M0 prostate cancer patients were randomized for conventional (open fields) and 3D conformal radiotherapy using beams eye view blocked fields with the same dose (66 Gy) and gross target volume-planning target volume margin (15 mm). Apart from the RTOG toxicity scoring system a patient self-assessment questionnaire was used to obtain detailed information on morbidity. RESULTS: At 2 years there is only a trend for less rectal toxicity (grade >/=1) in favor of the conformal radiotherapy (grade 1, 47 versus 40% and grade 2, 10 versus 7% for conventional and conformal radiotherapy, respectively (P=0.1). A significant relation was found between late rectal toxicity (grade >/=1) and the volume of the anus and rectum exposed to >/=90% tumor dose (TD). A highly significant relationship is observed between acute rectum and anal toxicity and late rectal toxicity. The patient self-assessment questionnaire analysis revealed that patients are most bothered by compliance related symptoms like urgency, soiling and fecal loss. In a multivariate analysis, all other variables loose significance, when anal volume exposed to >/=90% TD and pre-treatment defaecation frequency are accounted for. Late anal toxicity is low and related only to acute anal toxicity. Late bladder toxicity is related solely to pre-treatment frequency and overall urological symptoms. The incidence of grade 2 toxicity increases with a factor 2.5-4 when (stool or urine) frequency is unfavorable at the start of treatment. CONCLUSIONS: Conformal radiotherapy at the dose level of 66 Gy does not significantly decrease the incidence of rectal, anal and bladder toxicity compared to conventional radiotherapy. There is a significant relationship between acute and late toxicity and the anal volume exposed to 90% TD. Intestinal (and urological) symptoms at start have a major impact on late toxicity.  相似文献   
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Glucocorticoids play an important role in the treatment of a number of hematological malignancies, such as multiple myeloma. The effects of glucocorticoids are mediated through the glucocorticoid receptor alpha, the abundance of which can be modulated by alternative splicing of the glucocorticoid receptor mRNA. Two splice variants of the glucocorticoid receptor mRNA have been described: glucocorticoid receptor beta, which reportedly has a dominant negative effect on the actions of the glucocorticoid receptor alpha, and glucocorticoid receptor P, of which the effects are unknown. In this study, we have investigated the expression levels of these two splice variants at the mRNA level in multiple myeloma cells and in a number of other hematological tumors. Although the glucocorticoid receptor beta mRNA was, if at all, expressed at very low levels, considerable amounts (up to 50% of the total glucocorticoid receptor mRNA) glucocorticoid receptor P mRNA was present in most hematological malignancies. In transient transfection studies in several cell types and in multiple myeloma cell lines, the glucocorticoid receptor P increased the activity of the glucocorticoid receptor alpha. These results suggest that the relative levels of the glucocorticoid receptor alpha and the glucocorticoid receptor P may play a role in the occurrence of glucocorticoid resistance in tumor cells during the treatment of hematological malignancies with glucocorticoids.  相似文献   
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Due to variation in individual susceptibility, only a fraction of all individuals exposed to environmental carcinogens will develop cancer. Our aim was to assess whether mutagen sensitivity plays a role in developing urothelial cell carcinoma (UCC) and whether this sensitivity is different in familial and non-familial cases. Intrinsic susceptibility was quantified by a mutagen sensitivity assay (mean number of chromatid breaks per cell after damage induction with bleomycin in the late S-G2 phase of the cell cycle). Patients were classified as sporadic (n = 25), familial (2 patients in 1 nuclear family, n = 23) or hereditary (2 patients <60 years or 3 patients in 1 nuclear family, n = 13) and compared with control subjects without a history of cancer. Information on demographic factors, smoking history and family history of UCC was collected by postal questionnaires. Differences in mutagen sensitivity were assessed by ANOVA and logistic regression analysis. Overall, UCC patients showed a higher mutagen sensitivity score compared with control subjects [mean number of chromatid breaks per cell 0.91, 95% confidence interval (CI) 0.84-0.97, and 0.74, 95% CI 0.69-0.79, respectively; p = 0.001). Sporadic and familial patients exhibited the highest susceptibility (0.94, 95% CI 0.82-1.06, and 0.93, 95% CI 0.83-1.03, respectively). Hereditary patients (0.79, 95% CI 0.72-0.86) showed a susceptibility similar to controls. Mutagen sensitivity increases the risk of non-hereditary UCC. The relatively low mutagen sensitivity score among hereditary patients points to a different carcinogenic pathway.  相似文献   
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Somatostatin analogues, labeled with gamma-emitting radionuclides, are of potential value in the localization of somatostatin receptor-positive tumors with gamma camera imaging. We investigated the application in man of a radioiodinated analogue of somatostatin, 123I-Tyr-3-octreotide, which has similar biologic characteristics as the native peptide. The radiopharmaceutical is cleared rapidly from the circulation (up to 85% of the dose after 10 min) mainly by the liver. Liver radioactivity is rapidly excreted into the biliary system. Until 3 hr after injection, radioactivity in the circulation is mainly in the form of 123I-Tyr-3-octreotide. Thereafter, plasma samples contain increasing proportions of free iodide. Similarly, during the first hours after injection, radioactivity in the urine exists mainly in the form of the unchanged peptide. Thereafter, a progressive increase in radioiodide excretion is observed, indicating degradation of the radiopharmaceutical in vivo. Fecal excretion of radioactivity amounts to only a few percent of the dose. The calculated median effective dose equivalent is comparable with values for applications of other 123I-radiopharmaceuticals (0.019 mSv/MBq).  相似文献   
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Background  

Firearms are the most commonly used weapon to commit homicide in the U.S. Virtually all firearms enter the public marketplace through a federal firearms licensee (FFL): a store or individual licensed by the federal government to sell firearms. Whether FFLs contribute to gun-related homicide in areas where they are located, in which case FFLs may be a homicide risk factor that can be modified, is not known.  相似文献   
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Objective To determine the cell content and purity of Ficoll-separated peripheral blood mononuclear cells and granulocyte isolates in sepsis patients compared to healthy controls. Design and setting Prospective study in the adult and pediatric intensive care departments of the Erasmus University Medical Center in the Netherlands. Patients Three sepsis patients (two adults, one child) and four healthy controls. Measurements and results Blood leukocytes were separated by Ficoll into an interface and a bottom fraction. The cell content and purity was analyzed by cytospin and flow-cytometric immunofluorescence. In sepsis patients, the interface consisted of 11–52% mononuclear cells only, due to high contamination with granulocytes (48–89%). This was in contrast to a high proportion of mononuclear cells (88–100%) in healthy controls. The bottom fraction showed a cell purity of ≥ 92% polymorphonuclear granulocytes in sepsis patients as well as in healthy controls. Conclusions Ficoll-separated leukocytes of sepsis patients are not suitable for studying mononuclear cells but can be used for studying granulocytes with high purity. The mononuclear cell fraction is highly contaminated with granulocytes. Additional separation techniques are necessary to obtain a pure cell fraction.  相似文献   
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We studied the effect of recombinant interferon-beta1b (IFN-beta1b) on the sensitivity to glucocorticoids (GC) and on the number of GC receptors (GCR) in the human monocytic cell line THP-1. We found that IFN-beta1b augments the suppressive effect that dexamethasone has on the stimulated production of tumor necrosis factor-alpha (TNF-alpha), most likely related to the increased number of GCR observed after exposure to IFN-beta1b. This provides a possible clue to the mechanism of action of IFN-beta in multiple sclerosis.  相似文献   
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Purpose: To determine the efficacy of sildenafil citrate (Viagra) in patients with erectile dysfunction after three-dimensional conformal external beam radiotherapy (3D-CRT) for prostate cancer.

Methods and Materials: 406 patients with complaints of erectile dysfunction and who completed radiation at least 6 months before the study were approached by mail. 3D-CRT had been delivered (mean dose 68 Gy). Sixty patients were included and entered a double-blind, placebo-controlled, cross-over study lasting 12 weeks. They received during 2 weeks 50 mg of sildenafil or placebo; at Week 2 the dose was increased to 100 mg in case of unsatisfactory erectile response. At Week 6, patients crossed over to the alternative treatment. Data were collected using the International Index of Erectile Function (IIEF) questionnaire, and side effects were recorded.

Results: Mean age was 68 years. All patients completed the study. For most questions of the IIEF questionnaire there was a significant increase in mean scores from baseline with sildenafil, but not with placebo. Ninety percent of the patients needed a dose adjustment to 100 mg sildenafil. Side effects were mild or moderate.

Conclusion: Sildenafil is well tolerated and effective in improving erectile function of patients with ED after 3D-CRT for prostate cancer.  相似文献   

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