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51.
BACKGROUND: Bleeding isolated gastric varices with a spontaneous portosplenorenal shunt are difficult to control. The urgent use of transjugular retrograde obliteration (TJO) to prevent early rebleeding and to improve early mortality has not yet been demonstrated. We report our experience with this technique in patients with isolated gastric varices after treatment of acute bleeding. METHODS: We reviewed our experience of 6 patients with isolated gastric varices with a spontaneous portosplenoral shunt treated with TJO after treatment of acute bleeding. We basically applied endoscopic glue embolization using cyanoacrylate monomer for treatment of acute bleeding. TJO was a method using an occlusive balloon catheter to control a spontaneous portosplenorenal shunt flow while injecting sclerosant retrograde into the gastric varices. RESULTS: Treatment of acute bleeding was achieved immediately by endoscopic glue embolization, endoscopic variceal ligation, and ligating the varices with sutures following anterior gastrotomy in 4, 1 and 1 patients, respectively, and then TJO was performed. Permanent hemostasis and variceal eradication was achieved in these 6, and they all survived. They were alive for 6-66 months without gastric variceal recurrence. CONCLUSIONS: We conclude that urgent TJO is effective in the prophylaxis of early and late rebleeding from isolated gastric varices in patients with a spontaneous portosplenorenal shunt.  相似文献   
52.
BACKGROUND AND PURPOSE: The accuracy of factors for predicting lymph node metastasis in patients with early-stage (stage I and II) mobile tongue carcinoma and prognostic factors associated with the clinical and pathological findings of lymph node metastasis were examined. MATERIAL AND METHODS: Between 1971 and 1998, 616 patients with early stage mobile tongue carcinoma were treated by brachytherapy with or without external irradiation. Neck lymph node metastasis occurred in a total of 237 cases, and 191 of them were not associated with primary failure. Neck dissection was performed in 169 of these 191 cases, and 16 cases were treated by radiotherapy. A pathological analysis was possible in 159 of the 169 neck dissection cases. RESULTS: There were 88 tongue cancer recurrences, and the incidence of neck metastasis was 38% (191/528) in the cases of primary controlled early tongue carcinoma, and 25% (38/151) and 41% (153/377), in stage-I and -II carcinoma, respectively. Neck metastasis was diagnosed within 12 months in 80% of cases, and within 24 months in 95%. Macroscopic appearance, tumor thickness and tumor length were identified as significant risk factors by a univariate analysis, but macroscopic appearance was the only significant risk factor identified by a multivariate analysis (P<0.001). The incidence of cervical lymph node metastasis was 62% among the invasive/ulcerative type tongue carcinomas, and was lower among the superficial type and exophytic/nodular type (20 and 35%, respectively). Regional and/or distant failure occurred in 75 of the 169 neck dissection cases (44%). The incidence of regional/distant failure was extremely high (49/68=72%) in the extra-nodal invasion group, and extra-nodal invasion was found even in small metastatic node less than 1 cm in length (20%). CONCLUSIONS: The macroscopic appearance of the primary tongue carcinoma has a major impact on the incidence of lymph node metastasis in patients with early tongue cancer, and extra-nodal invasion was the dominant risk factor for regional and distant failure. Treatment policy for clinically negative neck metastasis in early tongue cancer patients should be determined after considering the possibility of neck metastases and the morbidity associated with elective neck dissection.  相似文献   
53.
The purpose was to compare three-dimensional (3D) constructive interference in steady state (CISS) and conventional spin-echo (SE) MR imaging in tumor volume measurements of acoustic neuromas. Twenty-two patients with acoustic neuromas were examined using high-resolution 3D-CISS and SE imaging at a 1.5-T system. Tumor volume determined by SE imaging with the ellipsoid formula was overestimated by 692 mm(3)(35%) on average as compared with that at 3D-CISS with the voxel-count method (the reference standard). Intra- and interobserver variations in SE imaging were poor as compared with 3D-CISS imaging. However, tumor volume results with SE imaging showed a high correlation with those using 3D-CISS imaging (P <. 0001). On the basis of diameters shown on SE images, the tumor volume could be assessed using the following equation (P <.0001): (Tumor volume) = -26.407 + 0.387 x (maximum diameter along the pyramid) x(maximum diameter perpendicular to the pyramid) x (maximum height). J. Magn. Reson. Imaging 2000;12:826-832.  相似文献   
54.
The purpose of the study was to determine the diagnostic accuracy of breath-hold contrast-enhanced three-dimensional (3D) magnetic resonance (MR) angiography in Takayasu arteritis. Thirty patients suspected of having Takayasu arteritis were examined with MR angiography and conventional angiography. Takayasu arteritis was diagnosed in 20 of these patients. MR angiography was performed using a 1.5-T system after bolus injection of 0.1 mmol/kg of gadodiamide. MR angiography clearly depicted various vascular lesions in the aorta and its major branches in all 20 patients with Takayasu arteritis. It also depicted pulmonary artery lesions in 10 (50%) of the 20 patients. MR angiography accurately depicted 323 (98%) of 330 arteries, but 7 (2%) stenotic arteries were overestimated as occluded. The sensitivity and specificity of MR angiography for the diagnosis of Takayasu arteritis were both 100%. Breath-hold contrast-enhanced 3D MR angiography clearly depicts various vascular lesions in both the systemic and pulmonary arteries in Takayasu arteritis, thus allowing a definitive diagnosis of Takayasu arteritis.  相似文献   
55.
The purpose of this study was to evaluate anisotropy of the kidney by measurements of the apparent diffusion coefficient (ADC) using commercially available magnetic resonance (MR) imaging. Fifty-one consecutive patients underwent diffusion-weighted echoplanar MR imaging of the upper abdomen with five different strengths of motion probing gradients (b = 1.51, 55.3, 36.6, 317, and 932 sec/mm2) applied along the z-axis. Four ADC values for the upper pole and central portion of the kidney were calculated from four different b-value ranges and compared. The ADCs for the kidney calculated in the lower b-value ranges were significantly higher than those in the higher ranges. The ADCs for the upper pole portion were significantly higher than those for the central portion except for one in the highest b-value range. Diffusion in the kidney is anisotropic, probably due to the kidney's radially oriented structures such as renal vessels and tubules.  相似文献   
56.
BACKGROUND: Recent laboratory studies have suggested that cadmium is an estrogenic compound and may be a potential risk factor for breast cancer. METHODS: We investigated the relationship between urinary cadmium concentrations and serum concentrations of estrone, testosterone, and dehydroepiandrosterone sulfate in 164 postmenopausal Japanese women. RESULTS: There was a significant positive association between the urinary cadmium and serum testosterone levels after controlling for age and body mass index. The mean testosterone level was 28% higher in women with high urinary cadmium (> or = 3.00 microg/g creatinine) than in those with low urinary cadmium (< 2.00 microg/g creatinine). Urinary cadmium was not significantly associated with serum estrone and dehydroepiandrosterone sulfate levels. Additional adjustment for smoking, alcohol and reproductive factors including known risk factors for breast cancer did not substantially alter the results. CONCLUSION: Data suggested that cadmium exposure is associated with increased testosterone levels. As high testosterone levels have been associated with the risk of breast cancer, the involvement of cadmium exposure in breast cancer risk should be evaluated in future studies.  相似文献   
57.
The use of intermediate frequency (IF) magnetic fields (MFs) in occupational equipment and domestic appliances, such as inductive heating cookers, is increasing. The WHO indicated a lack of scientific evidence needed to assess the health risk of exposure to IF MFs. Male and female rats (24/group) were exposed to a 20 kHz, 0.2 mT(rms) or 60 kHz, 0.1 mT(rms) sinusoidal MF for 22 h/day from 14 days prior to and during mating. Copulated females were exposed until gestation day 7 and sacrificed thereafter. Mated males were sacrificed to examine MF exposure effects on spermatogenesis. Reproductive examinations were blinded, and experiments were duplicated per frequency to ensure reproducibility. No statistically significant, exposure-related changes were found in the estrous cycle, copulation and fertility indices, numbers of corpora lutea and implantation sites, or pre- and postimplantation loss. No reproducible changes were observed in sperm count, motility, or morphological abnormality, or in the weights of testes and epididymides after MF exposure. No significant abnormalities were observed in gross pathology or histopathology of the uterus, ovary, testis, and epididymis in the MF- or sham-exposed groups. MF exposure during the preimplantation period was not toxic to fertility or early embryogenesis under the experimental conditions.  相似文献   
58.
Rosai-Dorfman disease (RDD) is a rare histiocytic proliferative disorder with massive lymphadenopathy. We here describe RDD of a neonate who presented with paleness and hepatosplenomegaly but not lymph-node swelling. Routine laboratory studies showed anemia, thrombocytopenia, and an elevated value of γ-glutamyl transpeptidase. Histological examination of the liver revealed a proliferation of histiocytes with abundant eosinophilic cytoplasm, which were positive for S-100 protein and CD68 but not CD1a and did not reveal Birbeck granules. Radiological studies showed hepatosplenomegaly and a narrowing of the hepatic vein, which might have contributed to hypersplenism resulting in anemia and thrombocytopenia. This case is thought to be congenital RDD without lymphadenopathy.  相似文献   
59.
The expression and implications of gangliosides in human osteosarcomas have not been systematically analyzed. In this study, we showed that gangliosides GD3 and GD2 are highly expressed in the majority of human osteosarcoma cell lines derived from oral cavity regions. Introduction of GD3 synthase cDNA into a GD3/GD2-negative (GD3/GD2-) human osteosarcoma subline resulted in the establishment of GD3/GD2+ transfectant cells. They showed increased cell migration and invasion activities in wound healing and Boyden chamber invasion assays, respectively, compared to the control cells. When treated with serum, GD3/GD2+ cells showed stronger tyrosine phosphorylation of p130Cas, focal adhesion kinase, and paxillin than GD3/GD2- cells. In particular, paxillin underwent much stronger phosphorylation, suggesting its role in cell motility. Furthermore, we tried to dissect the roles of GD3 and GD2 in the malignant properties of the transfectant cells by establishing single ganglioside-expressing cells, that is, either GD3 or GD2. Although GD3/GD2+ cells showed the most malignant properties, GD2+ cells showed almost equivalent levels to GD3/GD2+ cells in invasion and migration activities, and in the intensities of tyrosine phosphorylation of paxillin. Among Src family kinases, Lyn was expressed predominantly, and was involved in the invasion and motility of GD3- and/or GD2-expressing transfectants. Furthermore, it was elucidated by gene silencing that Lyn was located in a different pathway from that of FAK to eventually lead paxillin activation. These results suggested that GD2/GD3 are responsible for the enhancement of the malignant features of osteosarcomas, and might be candidate targets in molecular-targeted therapy.  相似文献   
60.
Context  Little is known about the incidence of secondary neoplasms after 15 to 20 years in children and adolescents who were treated for acute lymphoblastic leukemia. Objectives  To investigate the cumulative incidence of secondary neoplasms in pediatric patients treated for acute lymphoblastic leukemia over 30 years and to characterize late-occurring tumors. Design, Setting, and Patients  Retrospective study of 2169 patients with acute lymphoblastic leukemia treated between 1962 and 1998 at St Jude Children's Research Hospital, Memphis, Tenn, who achieved complete remission and had a median follow-up time of 18.7 years (range, 2.4-41.3 years). Main Outcome Measures  Cumulative incidences of secondary neoplasms in first remission and standard incidence ratios of observed rates compared with rates of cancer development in the general US population. Results  Secondary neoplasms developed as the first event in 123 patients and comprised 46 myeloid malignancies, 3 lymphomas, 14 basal cell carcinomas, 16 other carcinomas, 6 sarcomas, 16 meningiomas, and 22 other brain tumors. The cumulative incidence of secondary neoplasm was 4.17% (SE, 0.46%) at 15 years and increased substantially after 20 years, reaching 10.85% (SE, 1.27%) at 30 years. When meningiomas and basal cell carcinomas were excluded, the overall cumulative incidence was 3.99% (SE, 0.44%) at 15 years and 6.27% (SE, 0.83%) at 30 years, representing a 13.5-fold increase in overall risk compared with the general population. The cumulative incidence of each tumor type at 30 years was 2.19% (SE, 0.32%) for myeloid malignancy, 0.17% (SE, 0.10%) for lymphoma, 3.00% (SE, 0.59%) for brain tumor, 4.91% (SE, 1.04%) for carcinoma, and 0.57% (SE, 0.37%) for sarcoma. Conclusions  The cumulative incidence of secondary neoplasms increases steadily over 30 years after treatment of acute lymphoblastic leukemia. Although the majority of the late-occurring secondary neoplasms are low-grade tumors, the increase in incidence of more aggressive malignant neoplasms is significantly higher than expected in the general population. These results suggest that lifelong follow-up of acute lymphoblastic leukemia survivors is needed to ascertain the full impact of treatment and other leukemia-related factors on secondary neoplasm development.   相似文献   
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