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41.
Proximal-type epithelioid sarcomas are rare soft tissue neoplasms occuring in the soma or thigh and often repeat recurrence and metastasis. We present a case of locally recurrenced proximal-type epithelioid sarcoma that could be treated by regional excision alone. A 62-year-old man visited our institute for a growing mass in the perineal region. Computed tomography (CT) showed a periurethral tumor 22 x 13 mm in diameter in the perineal region. The tumor was excised regionally, and the pathological examination with immunohistochemical staining revealed that the tumor was proximal-type epithelioid sarcoma. Local recurrence of the tumor occurred 2 years 7 months later without any metastatic lesion, and regional excision was performed again. Pathological diagnosis was proximal type epithelioid sarcoma and it was identical to the primary tumor. The patient is free of the disease 1 year after the second surgery of the tumor.  相似文献   
42.
Recent advances in chemotherapy and chemoradiation therapy for colorectal cancer have made neoadjuvant treatment an eligible therapeutic option for selected cases of marginally resectable colorectal cancer. However, marginally resectable colorectal cancer is not well defined. The authors suggest that a primary lesion is marginally resectable if extended resection such as pelvic exenteration and pancreaticoduedenectomy are not completely curative. Even if the lesion itself is resectable, it is marginally resectable if it has unfavorable prognostic factors such as numerous metastases to the regional lymph nodes. Rectal cancer invading beyond mesorectal fascia, or having bilateral or multiple lateral lymph node metastasis, may also be marginally resectable. All locally recurrent lesions may be marginally resectable because the prognosis after surgical resection is poor. Multiple liver metastases, liver metastasis for which resection requires vascular reconstruction, and technically resectable liver metastasis with unfavorable prognostic factors, are also thought to be marginally resectable. Neoadjuvant chemotherapy regimens including oxaliplatin and irinotecan combined with bevacizumab, cetuximab and panitumumab may be effective for hastening the curability of such marginally resectable tumors. For primary advanced rectal cancer and locally recurrent rectal cancer, neoadjuvant radiation combined with chemotherapy using oxaliplatin and irinotecan are being explored. A number of clinical trials are currently ongoing, and are expected to clarify the effectiveness of neoajuvant treatment for marginally resectable colorectal cancer.  相似文献   
43.
A 51-year-old woman came to our hospital after a medical check -up. She suffered from abdominal distension. Abdominal CT revealed the abdominal cavity filled with omental cake. The preoperative diagnosis was unassertive. Laparotomy through midline incision was performed. The bulk of the omental tumor occupied the abdominal cavity, but infiltrated the bowel or abdominal wall less. Fractional resection of the tumor, right hemicolectomy, sigmoidectomy, wedge resection of small intestine and left ovariectomy were performed in parallel. Resected specimens weighed 6. 6 kg in total. The operation was considered palliative because of the peritoneal dissemination. Postoperative intraabdominal administration of cisplatin(50mg) made the ascites disappear. She was discharged 3 weeks after the operation. The final diagnosis was liposarcoma(myxoid type), and 5 courses of adjuvant chemotherapy with adriamycin and ifosfamide were performed. No relapse was found 11 months after the operation, but tumor regrowth occurred in the thoracic and abdominal cavity and the patient died 14 months after the operation.  相似文献   
44.
We newly synthesized organic selenium compounds (5-membered ring compounds) including 2-selenoxo-1,3-thiazolidin-4-ones (compounds A) and 3-alkoxy-4,5-dihydro-5-selenoxo-1H-1,2,4-triazole-1-carboxylates (compounds B). To address whether these compounds show antioxidative effects, we also examined their superoxide radical (O(2) (-))-scavenging effects. Moreover, we examined the effects of compound Aa on the activation of mitogen-activated protein kinase/extracellular signal-regulated protein kinases (MAPK/ERK1/2) and suppression of hydrogen peroxide-induced cytotoxicity in rat pheochromocytoma cells (PC12 cells). We evaluated the O(2) (-)-scavenging activities of the compounds by a chemiluminescence method, and activation of ERK1/2 in PC12 cells was evaluated by Western blot analysis. At 166 μmol/L, the O(2) (-)-scavenging activities were markedly different among compounds A and B. 3-(2,6-Dimethylphenyl)-2-selenoxo-1,3-thiazolidin-4-one (compound Aa) exhibited the strongest superoxide anion-scavenging activity among compounds A and B. The concentration necessary for 50% inhibition of the activity (IC(50)) of compound Aa was 25.9 μmol/L. Compound Aa activated ERK1/2 of the PC12 cell, as did ebselen, and suppressed hydrogen peroxide-induced cytotoxicity more potently than ebselen. In addition, the toxicity of compound Aa was less than that of ebselen. From these results, it is assumed that compound Aa is a candidate drug to prevent oxidative stress-induced cell death.  相似文献   
45.
External radiotherapy using imaging technology for patient setup is often called image-guided radiotherapy (IGRT). The most important problem to solve in IGRT is organ motion. Four-dimensional radiotherapy (4DRT), in which the accuracy of localization is improved – not only in space but also in time – in comparison to 3DRT, is required in IGRT. Real-time tumor-tracking radiotherapy (RTRT) has been shown to be feasible for performing 4DRT with the aid of a fiducial marker near the tumor. Lung, liver, prostate, spinal/paraspinal, gynecological, head and neck, esophagus, and pancreas tumors are now ready for dose escalation studies using RTRT.  相似文献   
46.
This study used PET to measure the time course of the brain concentration of (18)F-labeled N-(4-acetyl-1-piperazinyl)-p-fluorobenzamide monohydrate (FK960), a novel antidementia drug, after oral administration to conscious rhesus monkeys. METHODS: Three young-adult male rhesus monkeys were tested. FK960 (0.1 mg/kg) containing about 370 MBq of (18)F-FK960 was administered orally to each monkey. Dynamic PET images were acquired for 4 h from 5 min after the administration. Arterial blood samples were withdrawn during PET scanning and were analyzed by an automatic well gamma-counter and thin-layer chromatography to determine the time course of authentic (18)F-FK960 activity concentration in plasma. FK960 concentrations in brain and plasma were calculated in units of mol/L using the specific activity of FK960 preparations. RESULTS: (18)F-FK960 penetrated the blood-brain barrier and underwent perfusion-dependent distribution in the entire brain. Maximal concentrations in the brain and plasma were 1.11 +/- 0.30 x 10(-7) mol/L (at 3.0 +/- 0.6 h after administration) and 4.04 +/- 1.29 x 10(-7) mol/L (at 2.0 +/- 1.1 h after administration), respectively. CONCLUSION: We succeeded in measuring the FK960 concentration in the brains of conscious monkeys and in plasma after oral administration at a dose of 0.1 mg/kg. The results suggested that this method can measure the FK960 concentration in the human brain, and a potential use of the PET technique in drug development was demonstrated.  相似文献   
47.
Background To clarify the biologic characteristics of hereditary nonpolyposis colorectal cancer (HNPCC), an investigation was made of the association of this cancer with mutations of theTP53 (aliasp53) and K-ras genes, and with DNA ploidy. Methods Samples from 19 patients with HNPCC and from 56 patients with sporadic colorectal cancer were analyzed by polymerase chain reaction-single strand conformation polymorphism and flow cytometric analyses. Results Mutations of thep53 gene were found in 7 (32%) of 22 samples from HNPCC patients, and K-ras mutations were found in 8 (44%) of 18 samples from HNPCC patients. Aneuploidy was noted in 8 (44%) of 18 samples. Each incidence in HNPCC was similar to the corresponding incidence in the sporadic colorectal cancers. Conclusion The results of this investigation indicate that HNPCC shows no difference from sporadic colorectal cancer in terms ofp53 and K-ras alterations, or DNA ploidy.  相似文献   
48.
We describe a patient presenting with trochlear nerve palsy and segmental sensory disturbance due to circumscribed mesencephalic hemorrhage. A 36-year-old man with no past illness visited our hospital complaining of sudden onset of diplopia, dysesthesia of the left face and upper extremity, and acuphenes of the left ear. Neurological examination revealed left trochlear nerve palsy and segmental sensory disturbance of the left side almost above T11 level. Pain and temperature sensation were disturbed, but vibration, joint position, graphesthesia, kinesthesia, and discrimination sensation were spared. Magnetic resonance imaging of the head, performed 7 days after onset, revealed acute to subacute phase hemorrhage at the right inferior colliculus. No abnormalities were identified on cerebral angiography. Symptoms gradually improved with conservative therapy. After about ten weeks, diplopia disappeared and area of sensory disturbance was reduced (disturbance of pain sensation reduced to about T4 level, temperature sensation to about T9). Segmental sensory disturbance usually accompanies spinal cord lesion. However, several cases of similar symptoms following cerebrovascular disease of the brainstem have been reported. Conversely, some reports have indicated that trochlear nerve palsy due to midbrain hemorrhage accompanies sensory disturbance contralateral to the lesion. The nature of sensory disturbance is thus variable. The present case suggests that segmental sensory disturbance might accompany trochlear nerve palsy caused by hemorrhage of the inferior colliculus, as intramedullary fibers of the trochlear nerve and spinothalamic tract are located nearby and somatotopy of the spinothalamic tract is preserved even at the level of the midbrain.  相似文献   
49.
A series of eight 5,6-dihydro-4H-1,3-thiazine derivatives was synthesized by the BF3 x Et2O-catalyzed reaction of selected alpha,beta-unsaturated ketones with thiobenzamide at room temperature. The antimycobacterial activities of these compounds were determined against Mycobacterium tuberculosis H37Rv (ATCC 27294) using the Alamar blue susceptibility assay. Three compounds, 5-hydroxy-3-phenyl-4-aza-2-thiabicyclo[3.3.1]none-3-ene 3a, 4-hydroxy-4-methyl-6-pentyl-2-phenyl-5,6-dihydro-4H-1,3-thiazine 3b, and 4-ethyl-4-hydroxy-2-phenyl-5,6-dihydro-4H-1,3-thiazine 3c exhibited inhibitory activities of 97, 77 and 76%, respectively, at a concentration of 6.25 microg/ml. The actual MIC99 for the most active of these compounds, 3a, was also determined to be >6.25 microg/ml. These results, and especially those for 3a, suggest that 1,3-thiazines are potential lead compounds in the search for new antitubercular agents.  相似文献   
50.
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