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91.
Prosthetic valve dysfunction (PVD) due to pannus formation is an infrequent but serious complication. A 72-year-old man who underwent aortic valve replacement was diagnosed with PVD and aneurysm of the Sinus of Valsalva. Multidetector-row computed tomography (MDCT) was used to examine the cause of PVD before reoperation. MDCT demonstrated that tissue regarded as pannus extended from the left ventricular septum into the pivot guard. These findings were confirmed by observations during reoperation. MDCT can be a useful diagnostic technique for the anatomical and functional evaluation of PVD.  相似文献   
92.
PURPOSE: To evaluate the practice process using the national average (NA); to compare differences in the process of care by age group; and to provide a preliminary outcome data for limited-stage small-cell lung cancer in Japan. METHODS AND MATERIALS: The Patterns of Care Study conducted a nationwide survey of the care process for Stage I-III small-cell lung cancer in Japan. Patients were divided into three age groups: <65 years (younger group, n = 73); between 65 and 74 years (intermediate group, n = 81); and >or=75 years (elderly group, n = 20). RESULTS: The NA for the total dose was 49.0 Gy, and for use of photon energy >or=6 MV, chemotherapy, and prophylactic cranial irradiation was 77.3%, 93.2%, and 1.69%, respectively. Age stratification had no impact on the variables of radiotherapy (RT) such as total dose and field size. Only 37% of patients received chemotherapy and thoracic RT concurrently. The proportion of patients who received chemotherapy and RT concurrently was 44%, 27%, and 25% of the younger, intermediate, and elderly groups, respectively (p = 0.029). Etoposide and cisplatin were less frequently used in the elderly group (>or=75 years old). Overall survival at 3 years for the entire group was 26%. The 3-year survival rate was 30% in the younger group, 28% in the intermediate group, and 9% in the elderly group. Variables found to have a significant impact on survival by multivariate analysis were the use of chemotherapy (p = 0.030), age (p = 0.032), and T stage (p = 0.042). CONCLUSION: Calculated NAs showed that the results of clinical study had favorably penetrated into the practice process in Japan. The results demonstrated that patient age significantly influenced the process of chemotherapy such as the use of etoposide and cisplatin for limited-stage small-cell lung cancer in Japan. More concurrent chemotherapy and thoracic RT and the application of prophylactic cranial irradiation for complete responders need to be investigated in the future.  相似文献   
93.
BACKGROUND: Two prospective studies reported in 1997 demonstrated that postoperative radiotherapy after mastectomy was not only associated with a higher loco-regional control rate but also with a higher overall survival rate. The purpose of this study is to clarify the processes of care for patients undergoing mastectomy and postoperative radiotherapy in Japan. METHODS: A national survey carried out in 1998-2000, involving 79 Japanese institutions by two-stage cluster sampling of institutions and patients, disclosed that 1124 patients with breast cancer had been treated between 1995 and 1997. Mastectomy followed by radiotherapy was performed on 258 patients. RESULTS: The compliance rates for pre-treatment evaluation, including history, physical examination and mammography, averaged approximately 50% (24-81%). The chest wall was irradiated in only 19% of the patients and regional node irradiation was carried out for 70-86%. Radiation treatment planning with the aid of computed tomography was done in only 29% of patients (university hospitals or cancer centers, 39%; other hospitals, 17%; P = 0.001). Hormonal therapy was administered to 56% of the patients who showed no endocrine responsiveness. Non-intensive chemotherapy, which did not include the use of anthracycline or taxol, was used in 55% of the patients who received chemotherapy. CONCLUSIONS: There is room for improvement regarding some aspects of radiotherapy and adjuvant systemic therapies. Especially in the field of radiotherapy, significant differences were found among the treatment techniques employed in various institutions.  相似文献   
94.
BACKGROUND: The Patterns of Care Study (USPCS) by the American College of Radiology (ACR) has made significant contributions to improvements in the procedures of care for patients with breast cancer in the USA. The purpose of this study was to identify problems associated with the process of care for patients undergoing post-mastectomy radiotherapy (PMRT) in Japan compared with those in the USA. METHODS: The Japanese Patterns of Care Study Subgroup (JPCS) conducted a national survey in 1998-2000, involving 79 institutions and using two-stage cluster sampling of institutions and patients, which showed that between 1995 and 1997 PMRT was performed on 258 patients. The survey of the USPCS, involving 55 institutions, found that 407 patients received PMRT between 1998 and 1999. RESULTS: More than three axillary positive nodes were detected in 54% of the patients covered by the JPCS and in 46% of those covered by the USPCS. The clinical set-up of radiation treatment was planned without the aid of computed tomography or X-ray simulation for 25% of the JPCS patients and for 6% of the USPCS patients. The chest wall of 31% of the JPCS patients and of 98% of the USPCS patients was irradiated. The JPCS showed that inappropriate radiation techniques such as parallel opposed fields for chest wall irradiation were used for 3% of the patients in academic facilities, but for 25% of those in non-academic facilities (P = 0.0002). CONCLUSION: There is ample room for improvement in radiation treatment planning and chest wall irradiation techniques in Japan.  相似文献   
95.
96.
Background. The purpose was to estimate retrospectively the outcome of patients with musculoskeletal sarcoma or malignant lymphoma treated with intraoperative radiotherapy (IORT).Methods. Between 1988 and 1999, definitive IORT in combination with surgical excision was performed in 24 patients with musculoskeletal sarcoma (malignant fibrous histiocytoma, 10; osteosarcoma, 6; liposarcoma, 2; chondrosarcoma, 1; synovial sarcoma, 1; Ewing's sarcoma, 1; angiosarcoma, 1; epithelioid sarcoma, 1; malignant schwannoma, 1) and 3 patients with malignant lymphoma. The tumor was excised by marginal margin excision, intralesional margin excision, or wide margin excision; 15–45Gy electrons was then delivered to the affected sites.Results. In the 8 patients without distant metastases at the first visit, 4 patients are alive 6.5–11.5 years after IORT, and 4 patients died <4.5 years after IORT. The incidence of local recurrence was 13%. In the 19 patients with distant metastases at the first visit, 3 patients are alive 2.5–6.7 years after IORT, and 16 patients died 0.2–5.7 years after IORT. The incidence of local recurrence was 45%. Complications after IORT were found in 5 patients: neuropathy, 1 patient; skin necrosis, 1 patient; myelopathy, 1 patient; enteritis ileus, 1 patient; and edema, 1 patient.Conclusion. IORT with a radiation dose of 15–45Gy in combination with surgical excision appeared to be useful for local control and to be more effective in patients without distant metastases at the first visit than in patients with distant metastases.  相似文献   
97.
Allogeneic bone marrow transplantation (BMT) is currently restricted to hematological malignancies because of a lack of antitumor activity against solid cancers. We have tested a novel treatment strategy to stimulate specific antitumor activity against a solid tumor after BMT by vaccination with irradiated tumor cells engineered to secrete granulocyte-macrophage colony-stimulating factor (GM-CSF). Using the B16 melanoma model, we found that vaccination elicited potent antitumor activity in recipients of syngeneic BMT in a time-dependent fashion, and that immune reconstitution was critical for the development of antitumor activity. Vaccination did not stimulate antitumor immunity after allogeneic BMT because of the post-BMT immunodeficiency associated with graft-versus-host disease (GVHD). Remarkably, vaccination was effective in stimulating potent and long-lasting antitumor activity in recipients of T-cell-depleted (TCD) allogeneic bone marrow. Recipients of TCD bone marrow who showed significant immune reconstitution by 6 weeks after BMT developed B16-specific T-cell-cytotoxic, proliferative, and cytokine responses as a function of vaccination. T cells derived from donor stem cells were, therefore, able to recognize tumor antigens, although they remained tolerant to host histocompatibility antigens. These results demonstrate that GM-CSF-based tumor cell vaccines after allogeneic TCD BMT can stimulate potent antitumor effects without the induction of GVHD, and this strategy has important implications for the treatment of patients with solid malignancies.  相似文献   
98.
In the present study, we investigated the diagnostic effectiveness of biochemical markers of bone turnover for the detection of bone metastasis from prostate cancer and changes in the levels of these markers caused by hormonal therapy. Ninety-five patients with prostate cancer were divided into one of three groups: 26 patients with bone metastasis (BM(+)), 35 patients without bone metastasis on nonhormonal therapy (BM(−)HT(−)) and 34 patients without bone metastasis on hormonal therapy (BM(−)HT(+)). All patients in the BM(+) group had received hormonal therapy. Serum or urinary levels of the following biochemical markers of bone turnover were examined: bone-specific alkaline phosphatase (B-ALP), osteocalcin (OC), type I procollagen C-propeptide (PICP), type I collagen cross-linked C-telopeptide (ICTP), C-telopeptide fragment (CTx), N-telopeptide fragment (NTx), total pyridinoline (T-Pyr), total deoxypyridinoline (T-D-Pyr) and free deoxypyridinoline (F-D-Pyr). The BM(+) group showed significantly higher values than the BM(-)HT(-) group for B-ALP, PICP, NTx, CTx, T-Pyr, T-D-Pyr, and F-D-Pyr. Compared with the BM(−)HT(+) group, the BM(+) group showed significantly higher values for B-ALP, ICTP, NTx, T-Pyr and T-D-Pyr. The levels of B-ALP, NTx, CTx, T-D-Pyr and F-D-Pyr were significantly different between the BM(−)HT(−) and BM(−)HT(+) groups. All markers, except OC and CTx, significantly were correlated with the extent of bone metastasis on bone scintigraphy. Of all markers, receiver operating characteristic (ROC) analyses revealed B-ALP and F-D-Pyr to be the most sensitive and specific for differentiation between the BM(+) and BM(−)HT(−) groups with regard to bone formation and resorption, respectively. In contrast, B-ALP and ICTP were most sensitive and specific for differentiation between the BM(+) and BM(−)HT(+) groups. The results suggest that hormonal therapy greatly affects the efficacy of PICP, CTx and F-D-Pyr in the diagnosis of bone metastasis, whereas its effects on ICTP are small. Although bone metabolic markers would be useful in the diagnosis of bone metastasis from prostate cancer, the effects of hormonal therapy on bone metabolism should be kept in mind in their evaluation. Received: November 18, 1999 / Accepted: June 12, 2000  相似文献   
99.
Low bone volume with reduced trabecular thickness and the increased eroded surface are common features in periarticular bone histology in patients with rheumatoid arthritis;however, there is no consensus on the change in bone formation. Main histological changes of iliac bone in rheumatoid arthritis are reduced bone volume, low trabecular thickness, and decreased trabecular connectivity caused by increased bone resorption. Results in parameters for bone formation are conflicting. The experimental model for arthritis demonstrates that bone turnover changes with the severity of arthritis.  相似文献   
100.
Carrot juice was administered orally to BALB/c mice immunized intraperitoneally with dinitrophenylated (DNP)-OVA for about 1 month. The titers of DNP-specific IgE, DNP-specific IgG, and the levels of total IgE in mouse sera were determined. The DNP-specific IgE production by mice fed carrot juice was significantly inhibited. On the other hand, the DNP-specific IgG production and the level of total IgE in mice fed carrot juice were not significantly different from those in control mice. We also examined the effect of feeding carrots on immediate-type hypersensitivity. One hour after antigen stimulation, the ears of mice fed carrots swelled less than those of control mice. Furthermore, the rise in serum histamine in the mice fed carrots under active systemic anaphylaxis was lower than in controls. We then examined the pattern of cytokine production by spleen cells from mice followed by restimulation with DNP-OVA in vitro. The spleen cells from the mice fed carrots produced more interferon-gamma than those from the control group. In contrast, the spleen cells from the mice fed carrots produced less interleukin-4 than those from the control group. Furthermore, the interleukin-12 production of the spleen cells from mice fed carrots was also higher than that of the control group. These findings suggest that feeding carrots improves the helper T cell (Th)1/Th2 balance, inhibiting specific IgE production and antigen-induced anaphylactic response.  相似文献   
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