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81.
Significant progress has been made in the past 20 years in understanding the biological basis of hyperthermia-induced cytotoxicity, thermoenhancement of radiation therapy and chemotherapy, and in the development of clinically applicable microwave, radiofrequency, ultrasound and thermometry equipment. Numerous uncontrolled trials have suggested strongly that hyperthermia in conjunction with radiation therapy or chemotherapy may contribute to improved local control rates for recurrent or metastatic cancer without excessive morbidity. Carefully designed and well-controlled site and disease-specific prospective randomized trials with standardized hyperthermia and radiation therapy techniques, adequate thermometry, precise end points for tumour control and normal tissue toxicity are now essential to establish the role of hyperthermia in cancer management. Criteria for tumour site selection will be explored for trials employing radiation therapy and local-regional hyperthermia. Examples of sites selected will be presented which represent areas that can, with current technology, usually be adequately heated, and in which significant patient benefit may result from improved local-regional control.  相似文献   
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83.
The hematopoietic cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) is being used in clinical trials for its potential in the treatment of hematopoietic insufficiency due to various causes. Involvement of leukotrienes in the effects of GM-CSF is suggested by analytical and pharmacologic evidence obtained in vitro. However, until now no data in support of a role of leukotrienes in GM-CSF action in vivo have been presented. In the present investigation this question was approached by measurement of endogenous cysteinyl leukotriene formation in patients treated with the cytokine for cytopenia induced by cytostatic drugs or for refractory anemia with excess of blasts (RAEB). Endogenous cysteinyl leukotriene formation was assessed by determination of urinary leukotriene metabolites using combined high-performance liquid chromatography and radioimmunoassay analysis. After GM-CSF administration a distinct increase in urinary cysteinyl leukotrienes was found in the cytopenic and the RAEB patients that ranged from 2.3- to 57-fold and 2.4- to 333-fold, respectively. In the cytopenic patients the increase in leukotriene production was correlated to an expansion of peripheral blood leukocytes; RAEB patients responded to GM-CSF with enhanced leukotriene biosynthesis even if the peripheral leukocytes decreased, possibly due to an abnormal number and/or irritability of leukotriene-producing cells. The increase in endogenous leukotriene production during therapy with GM-CSF may indicate that leukotrienes play a role in GM-CSF action in vivo.  相似文献   
84.
From March 1984 to February 1988, 70 patients with 179 separate treatment fields containing superficially located (less than 3 cm from surface) recurrent or metastatic malignancies were stratified based on tumor size, histology, and prior radiation therapy and enrolled in prospective randomized trials comparing two versus six hyperthermia treatments as an adjunct to standardized courses of radiation therapy. A total of 165 fields completed the combined hyperthermia-radiation therapy protocols and were evaluable for response. No statistically significant differences were observed between the two treatment arms with respect to tumor location; histology; initial tumor volume; patient age and pretreatment performance status; extent of prior radiation therapy, chemotherapy, hormonal therapy, or immunotherapy; or concurrent radiation therapy. The means for all fields of the averaged minimum, maximum, and average measured intratumoral temperatures were 40.2 degrees C, 44.8 degrees C, 42.5 degrees C, respectively, and did not differ significantly between the fields randomized to two or six hyperthermia treatments. The treatment was well tolerated with an acceptable level of complications. At 3 weeks after completion of therapy, complete disappearance of all measurable tumor was noted in 52% of the fields, greater than or equal to 50% tumor reduction was noted in 7% of the fields, less than 50% tumor reduction was noted in 21% of the fields, and continuing regression (monotonic regression to less than 50% of initial volume) was noted in 20% of the fields. No significant differences were noted in tumor responses at 3 weeks for fields randomized to two versus six hyperthermia treatments (p = 0.89). Cox regression analyses were performed to identify pretreatment or treatment parameters that correlated with duration of local control. Tumor histology, concurrent radiation doses, and tumor volume all correlated with duration of local control. The mean of the minimum intratumoral temperatures (less than 41 degrees C vs. greater than or equal to 41 degrees C) was of borderline prognostic significance in the univariate analysis, and added to the power of the best three covariate model. Neither the actual number of hyperthermia treatments administered nor the hyperthermia protocol group (two versus six treatments) correlated with duration of local control. The development of thermotolerance is postulated to be, at least in part, responsible for limiting the effectiveness of multiple closely spaced hyperthermia treatments.  相似文献   
85.
Spontaneous pregnancy loss affects 15-18% of couples, and a number of potential causes are being discussed. The purpose of the present study was to assess if angiogenic disorders in the decidua of early human pregnancy could be related to spontaneous abortions. First trimester human decidua from elective terminations of normally progressing pregnancies and from missed abortions were investigated immunohistochemically. We quantified vessel density in decidua from normal pregnancies and from abortions by von Willebrand factor (vWF), platelet endothelial cell adhesion molecule (PECAM-1) and CD34 staining. Decidual blood vessel expression of alphavbeta3 integrin was also investigated. Significant increase (P < 0.02) in vessel density was observed in decidua parietalis of abortions, compared to decidua basalis. This increase was detected on slides stained for vWF and CD34, but not for PECAM-1. We observed a 15% increase analysing with vWF and a 77% increase with CD34 staining. alphavbeta3 integrin expression was not significantly different, neither in decidua parietalis from abortion, nor parietalis from normal pregnancies. Our data suggest that the increased vascularization in decidua parietalis from abortions could reflect complex disorders, such as specific cytokine expressions and hypoxia phenomena during the development of the decidua.  相似文献   
86.
From 1969 to 1982, 183 patients with previously untreated stages IIIB and IV Hodgkin's disease and relapsing Hodgkin's disease after radiation therapy were treated with combination chemotherapy plus low-dose irradiation (CRT). One hundred fifty patients who achieved a complete response (CR) were analyzed for risk of developing a second neoplasm. Median follow-up has been 8.3 years. Actuarial survival of all patients is 74% at 10 years with a relapse-free survival of 68%. An additional 24 patients with stage IIIA disease were also treated with CRT. There were 22 CRs at risk who were analyzed. Median follow-up has been 3+ years with an actuarial survival of 90% at five years and a relapse-free survival of 83%. Second neoplasms have developed in 14 of 172 patients at risk: acute nonlymphocytic leukemia (ANLL; five patients); aggressive histology non-Hodgkin's lymphoma (NHL; three patients); and a variety of solid neoplasms (six patients). Time to second neoplasm diagnosis after initial treatment ranged from 12 to 141 months. Five patients were older than 40 years. At the time of diagnosis of the second malignancy, 11 patients were free of Hodgkin's disease (for 36 to 141 months) and three were receiving therapy for recurrent Hodgkin's disease. The 10-year actuarial risk (%) of developing ANLL was 5.9 +/- 2.8; for NHL, the risk was 3.5 +/- 2.4, and for solid neoplasms, 5.8 +/- 3.0. Our results suggest that combination chemotherapy plus low-dose irradiation does not appear to significantly increase the risk of developing second neoplasms above that already reported for combination chemotherapy when administered as either initial or salvage treatment of Hodgkin's disease.  相似文献   
87.
88.
The GAT-specific suppressor T-cell factor (GAT-TsF) extracted from lymphoid cells from GAT-primed, nonresponder DBA/1 mice has been partially characterized. It is a protein that has affinity for GAT and determinants encoded by the I region of the H-2 complex. On the basis of specificity and avidity, GAT-TsF resembles anti-GAT-MBSA antibodies produced by DBA/1 mice in spite of the fact that it is too small to be classical antibody and has no constant-region determinants of heavy or light chains. Further, GAT or a fragment of GAT is associated with the GAT-TsF. GAT-TsF has been partially purified from the crude extract by absorption to GAT-Sepharose and elution with 0.4 to 0.6 KCl. GAT-TsF purified on the basis of its affinity for GAT bears I-region determinants but not detectable GAT or GAT fragment.  相似文献   
89.
90.
We have previously reported that two types of suppressor T cell factors (TsF) specific for L-glutamic acid50-L-tyrosine50 (GT) or L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT) can be distinguished based upon differences in their ability to suppress responses by allogeneic mice. Injection of GAT or GT induces a suppressor T cell subset that produces an antigen-binding, I-J+, genetically unrestricted, specific suppressor factor (TsF1). Injection of this factor plus small amounts of antigen induces a second-order suppressor T cell that produces an antigen- binding, I-J+, genetically restricted, specific suppressor factor (TsF2). In this report, we demonstrate that these two factors are also biochemically distinct. Monoclonal TsF1 molecules are composed of a single polypeptide chain that bears both the antigen-binding site and I- J determinant, whereas TsF2 molecules are composed of two disulfide- linked polypeptide chains, one of which is antigen-binding and I-J-, and the other, nonantigen-binding, I-J+. The antigen-binding chain must be added at culture initiation to achieve suppression, but the I-J+ chain can be added as late as day 3 with complete suppression observed. However, isolated chains from TsF2-producing hybridomas derived from three different haplotypes were unable to suppress immune responses when chains from heterologous TsF2 were mixed. Indirect evidence is presented that suggests that this restriction is because the chains fail to interact rather than the inability of the target cells to recognize both chains.  相似文献   
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