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961.
A 67-year-old man was referred to our department because of a mass in the pancreas tail. Pancreatic tail cancer with lymph node metastasis was diagnosed, based on various radiological findings. Computed tomography (CT) revealed a slightly enhanced tumor mass around the celiac plexus, and endoscopic retrograde pancreatography (ERP) showed complete obstruction of the main pancreatic duct at the tail, although magnetic resonance imaging (MRI) demonstrated no elevation of the mean pixel value of the tumor after gadolinium (Gd) injection, and tumor markers of pancreas cancer were within normal limits. At surgery, the mass around the celiac plexus was found to be blood coagulation, and the pancreas tail tumor was found to be a focal hematoma in the pancreas. Pathologically, the hematoma was not encapsulated, and it was diagnosed as hemorrhage in the pancreas parenchyma. Both hemorrhagic lesions were suspected to have developed respectively. It is difficult to distinguish pancreas hemorrhage from carcinoma in the pancreas with chronic pancreatitis, especially when the hemorrhage is small in size and there are other extrapancreatic hemorrhagic lesions. For such diagnosis, the superiority of MRI with Gd injection is indicated. Received: February 6, 2002 / Accepted: June 10, 2002 Offprint requests to: S. Matsuyama  相似文献   
962.
The aim of this study is to evaluate the biomechanical effects of multilevel foraminotomy and foraminotomy with double-door laminoplasty compared with foraminotomy with laminectomy. Using fresh human cadaveric specimens (C2-T1), sequential injuries were created in the following order: intact, bilateral foraminotomies (C3-C4, C4-C5, C5-C6), laminoplasty (C3-C6) using hydroxyapatite spacer, removal of the spacers, and laminectomy. Changes in the rotations of each vertebra in each injury status were measured in six loading modes: flexion, extension, right and left lateral bending, and right and left axial rotation. Foraminotomy alone and following laminoplasty showed no significant differences in motion compared with intact except in axial rotation. After removal of the spacers and following laminectomy, the motion increased significantly in flexion and axial rotation. The ranges of initial slack showed similar trends when compared with the results at maximum load. Clinical implications of these observations are presented.  相似文献   
963.
OBJECTIVE: Large cell neuroendocrine carcinoma of the lung is a newly recognized clinicopathologic entity. The clinical characteristics and optimal treatment of patients with large cell carcinomas are not yet established. The aim of this study was to define the clinicopathologic characteristics of large cell neuroendocrine carcinoma. METHODS: The histologic characteristics of the patients receiving an initial diagnosis of poorly differentiated non-small cell lung carcinoma (n = 484), small cell carcinoma (n = 55), carcinoid (n = 31), and large cell neuroendocrine carcinoma (n = 12) were retrospectively reviewed according to World Health Organization criteria. Immunohistochemistry was performed to confirm the neuroendocrine phenotype. The outcomes and other clinical characteristics of those patients with large cell neuroendocrine carcinoma were retrospectively analyzed and compared with those of patients with poorly differentiated carcinoma of other histologic types. RESULTS: A total of 87 patients were given a diagnosis of large cell neuroendocrine carcinoma after the histologic review. These patients comprised 3.1% of all patients undergoing resection for primary lung cancer during the same period. The overall 5-year survival was 57%. The 5-year survivals of patients with stage I, II, III, and IV disease were 67%, 75%, 45%, and 0%, respectively. There was no statistically significant difference between the overall survival of patients with large cell neuroendocrine carcinoma and those with other non-small cell lung cancers. There was a significant difference between the survival of patients with stage I large cell neuroendocrine carcinoma and that of patients with the same stage of other non-small cell lung carcinomas. The site of the first documented recurrence was locoregional in 12 patients (34%), distant metastases in 20 patients (57%), and both simultaneously in 3 patients. Locoregional lymph node recurrences were observed frequently. More than 80% of recurrences were found within 1 year after the operation. CONCLUSION: In terms of prognosis, large cell neuroendocrine carcinoma is distinctly different from other non-small cell lung cancers. The prognosis of large cell neuroendocrine carcinoma was poor, even for early stage disease; the prognosis of the stage I disease of large cell neuroendocrine carcinoma was poorer than that of the same stage of other non-small cell lung cancers. Because of its aggressive clinical behavior and poor prognosis, large cell neuroendocrine carcinoma should be recognized as one of the poorest prognostic subgroups among primary lung cancers, and therefore novel therapeutic approaches should be established.  相似文献   
964.
A 38-year-old man experienced an intermittent low-grade fever with generalized eruption, followed by rapidly progressive right hemiplegia. Neuroimaging revealed a ring-like enhanced mass in the left premotor cortex surrounded by marked perifocal edema. The syphilitic titer was high both in the serum and in the cerebrospinal fluid. Open biopsy of the lesion revealed the tumor consisted of inflammatory cells associated with plasmacyte infiltration to the perivascular region as well as to the dura, which is consistent with the definition of syphilitic gumma. The abnormalities in neurology and in neuroimaging improved dramatically after antisyphilitic treatment. Difficulties in differentiating a cerebral gumma from other diseases are discussed.  相似文献   
965.
Caspases play a major role in virtually all forms of apoptosis. Radiation is well known to induce apoptosis of crypt intestinal epithelial cells (IEC). Here, we examined the role of caspase-3 in radiation-induced IEC apoptosis. We demonstrate that while caspase-3 is present in IEC and activated upon irradiation, IEC in caspase-3-deficient mice partially underwent radiation-induced apoptosis. Typical morphological changes of IEC undergoing radiation-induced apoptosis (ie, blebbing, shrinkage, and nuclear condensation) can occur independently of caspase-3; however DNA fragmentation, as analyzed by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining, is mostly, but not entirely, caspase-3-dependent. Overall, these results demonstrate that radiation-induced crypt IEC apoptosis has both caspase-3-independent and -dependent components.  相似文献   
966.
We report the case of a 75-year-old woman with hepatitis C virus-related cirrhosis and recurrent hepatocellular carcinoma located just beneath the diaphragm. Computed tomography-guided percutaneous ethanol injection therapy was performed, because images of the tumor were hard to obtain on ultrasonography. The angle and depth of needle insertion were determined by using the geometric relationship between the target lesion and the skin insertion site on computed tomography scans. A 22-gauge needle was inserted through the right 6th intercostal space under local anesthesia. Computed tomography scanning was repeated to verify the needle position. After entry of the needle into the target lesion was confirmed, 10 mL of absolute ethanol was injected. This procedure caused transient mild pain, but there were no serious adverse effects such as pneumothorax or hemothorax. Three months after treatment, the lesion was not enhanced on dynamic computed tomography scanning, suggesting complete tumor ablation. At present, the patient is doing well. In conclusion, computed tomography-guided percutaneous ethanol injection therapy was safe and accurately achieved the desired tumoricidal effect in a patient with ultrasonically invisible hepatocellular carcinoma.  相似文献   
967.
BACKGROUND: Hypoxia can induce tissue injury, including apoptosis of endothelial cells. However, little is known about the effects of hypoxia on endothelial cell function. We assessed the effects of hypoxia inducible factor (HIF)-1alpha on the functional characteristics of endothelial cells, particularly on cell cycle regulators, by cationic liposome-mediated transfection of HIF-1alpha-expression vector into the cells. RESULTS: Transfection of the HIF-1alpha gene in endothelial cells resulted in (a) reduced proliferation and detachment of the cells; (b) up-regulation of intracellular p21waf1/cip1 and down-regulation of bcl-2; (c) reduced activities of cyclin-dependent kinase (CDK)-4 and CDK-6; (d) cell cycle arrest at G0/G1 phase; and (e) apoptosis of the cells. CONCLUSIONS: HIF-1alpha can induce cell cycle arrest, resulting in the reduced proliferation and apoptosis of endothelial cells, and the hypoxia-induced cell death may be involved by suppression of anti-apoptotic molecule, bcl-2.  相似文献   
968.
A clinical evaluation of uveitis-associated secondary glaucoma   总被引:12,自引:0,他引:12  
PURPOSE: To investigate the clinical features of secondary glaucoma associated with uveitis.METHODS: The subjects of the study were 1,099 patients with uveitis (1,604 eyes) treated at the Miyata Eye Hospital, Miyakonojo, Miyazaki, between October 1974 and January 2000. The intraocular pressure (IOP) and clinical data were analyzed retrospectively. Secondary glaucoma was diagnosed in the patients when IOP was higher than 21 mm Hg at two consecutive visits and they needed treatment with medication to control the high IOP.RESULTS: Secondary glaucoma was found in 293 eyes (18.3%) of 217 patients (19.7%) among the uveitis patients. The clinical entity with the highest incidence of secondary glaucoma was Posner-Schlossman syndrome in 100%, followed by sarcoidosis in 34.1%, herpetic anterior uveitis in 30.4%, Beh?et's disease in 20.8%, human leukocyte antigen-B27-related acute anterior uveitis in 20.0%, Vogt-Koyanagi-Harada's disease in 16.4%, and human T-lymphotropic virus type 1 uveitis in 16.2%. Among these 293 eyes with secondary glaucoma, the majority (72%) had active anterior uveitis at the time of high IOP. Only 7.5% of the secondary glaucoma eyes had peripheral anterior synechia wider than 180 degrees of the trabecular meshwork. Steroid-induced glaucoma was found in only 8.9% of the secondary glaucoma eyes. Surgical therapy, mainly trabeculectomy with anti-metabolites, was performed in 38 eyes and the post-surgical IOP was controlled under 20 mm Hg in 34 eyes. Despite the medical and surgical therapy for secondary glaucoma, visual field defect was found in 39% of the secondary glaucoma eyes.CONCLUSIONS: The incidence of secondary glaucoma in the 1,604 eyes with uveitis was 18.3%, but it differed depending upon the clinical entity of the uveitis. The evaluation and the management of IOP are very important in the treatment of patients with uveitis, in addition to the management of intraocular inflammation.  相似文献   
969.
To date, several tumor-suppressor genes responsible for the tumorigenesis of colorectal cancer have been identified. However, studies of loss of heterozygosity (LOH) have suggested several chromosomal regions which may contain additional tumor-suppressor genes for colorectal cancer. To determine the extent and variation of allelic loss on 22q, on which LOH has been frequently observed, a total of 68 sporadic colorectal cancers was examined for LOH on the chromosome arm by means of 16 polymorphic DNA markers. LOH was observed in 28 tumors (41 %), of which 9 showed LOH at all informative loci. The remaining 19 tumors showed variable patterns of partial loss on 22q, delimiting the smallest region of overlap (SRO) between D22S90 and D22S94. Moreover, LOH within the SRO correlated with a progression in terms of Dukes' stages. These results suggest that an additional tumor-suppressor gene for colorectal cancer may exist on 22q distally to the NF2 locus and that inactivation of the gene may possibly play a role in the progression or metastasis of colorectal cancers. © 1995 Wiley-Liss, Inc.  相似文献   
970.
Cytogenetic and molecular genetic analyses have shown that a tumor-suppressor gene for human meningioma is located on the long arm of chromosome 22. Recently, somatic mutations of the NF2 gene have been identified in sporadic meningiomas. However, tumorigenesis of certain cases of meningioma cannot be fully explained by inactivation of the NF2 gene alone. Thus, to obtain some indication as to the existence of another tumorsuppressor gene, it seemed important to re-examine the loss of heterozygosity (LOH) on 22q in sporadic meningioma. A total of 46 sporadic meningiomas was examined for LOH at 20 loci on 22q. LOH was observed in 29 tumors (63%), of which 13 (28%) showed different patterns of a partial loss of 22q. However, the NF2 locus was retained in one tumor that lost a more distal part of 22q. Moreover, 27 of the 28 tumors which showed LOH at the NF2 locus also lost alleles at more telomeric loci. These results raise the possibility that another tumor-suppressor gene for meningioma may exist on 22q and that its localization may be distal to the D22S102 locus. © 1995 Wiley-Liss, Inc.  相似文献   
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