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51.
Pseudoaneurysm is an uncommon and serious complication of infective endocarditis (IE). It is often fatal because of its rapid progress, high rates of rupture and recurrence, and worsening effects on the systemic condition. We report the rare case of a patient who developed a pseudoaneurysm of the sinus of Valsalva two months after emergency aortic valve replacement for active IE. At the previous operation, we had directly closed a small fistulous hole in the non-coronary sinus of Valsalva using two mattress sutures with autologous pericardial pledgets, because the tissue surrounding the hole did not appear to be infected on visual inspection. A pseudoaneurysm developed from this portion due to detachment of sutures. If the fistula had been completely resected during the first surgery instead of performing a simple closure, the pseudoaneurysm of the sinus of Valsalva would not have formed. However, the primary aim of the first emergency surgery was to spare the life of a critically ill patient. In the second surgery, the pseudoaneurysm was completely resected with the aortic wall--including the non-coronary sinus of Valsalva and the communicating hole. Then, patch plasty of the non-Valsalva sinus was successfully performed.  相似文献   
52.
Malignant pulmonary artery tumors represented by sarcomas are rare, but fatal. Early diagnosis and radical surgical resection offer the only chance for survival. However, surgical intervention has some challenging aspects, and prognosis is poor even after tumor resection. We report a case of a pulmonary artery sarcoma between the right ventricular outflow tract and the pulmonary artery branches. The tumor was aggressively extracted with reconstruction using a cryopreserved pulmonary valved allograft, followed by adjuvant chemoradiotherapy. At 56 months after surgery, the patient is well without any evidence of recurrence, demonstrating that aggressive surgical resection with adjuvant chemoradiotherapy can prolong survival.  相似文献   
53.
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented.  相似文献   
54.
Takotsubo cardiomyopathy (TCM) is a relatively new concept in cardiovascular disease. The clinical symptoms of TCM are similar to those of a myocardial infarction, but both the mechanism and the management of TCM are different from those of myocardial infarction. The cause of TCM is unclear, but it is suggested to occur in conjunction with excessive circulating catecholamines due to stress. Thus, control of the stress reaction and restriction of catecholamine levels are considered important for prevent of TCM onset. We report the dental management of a patient with intellectual disability who had anamnesis of TCM and cardiopulmonary arrest under restraint during a previous dental appointment in another dental clinic. We used intravenous sedation with both midazolam and propofol, by which the excessive hormonal reaction that caused TCM onset and cardiopulmonary arrest was controlled, for dental treatment in our facility. All planned dental treatment was then performed without any problems.  相似文献   
55.
Background Few previous studies have analyzed the incidence of bone metastases in a defined population of Japanese breast cancer patients and their prognosis after chemotherapy. Methods This is a retrospective cohort study. We investigated 695 patients who underwent surgery for breast cancer. The strategy of adjuvant therapy was as follows. Patients with both estrogen receptors (ERs) and progesterone receptors (PgRs) had endocrine therapy as initial adjuvant therapy (n = 239). Patients with neither ERs nor PgRs had chemotherapy. When metastasis to other organs, including bone, was identified, patients received chemotherapy. The survival rates after surgery and after the onset of bone metastasis, as well as the incidence of bone metastasis, were calculated. We also evaluated the prognostic and predictive factors. Results Bone metastases developed in 148 of 695 patients. All 148 received chemotherapy, and 121 of them developed spinal metastases. The 5-year survival rate after bone metastases was 26.1%. Prognostic factors for bone metastases were visceral metastases and PgR status. Cord compression was observed in 17 of the 148 patients, with the thoracic spine being the most common. The 1-year survival rate for patients with bone metastases who received chemotherapy was 66.3%, whereas that of patients with paralysis after spinal metastases was 17.6%. Within 6 months of the development of spinal cord compression, 70.6% of the patients died. Conclusions We reported the incidence and prognostic factors for a defined population of Japanese breast cancer patients with bone and spinal metastases. Our results suggest that the expected survival time for patients with paralysis who received adequate endocrine therapy or chemotherapy is generally poor. However, to detect a predictive factor of long survival after paralysis and establish the indications for surgery, a comparative study among large groups of patients with paralysis and with different backgrounds is necessary.  相似文献   
56.
A rare adult case of a left ectopic ureterocele associated with a duplex horseshoe kidney is reported. To the best of our knowledge, only one pediatric case of horseshoe kidney with an ectopic ureterocele has been reported. The present case was successfully treated by ureteropyelostomy, upper ureterectomy and unroofing of the ureterocele. The patient is currently followed with excretory urograms and renograms.  相似文献   
57.
The thymoma-prone rat of the BUF/Mna strain is a useful model for human thymoma. In this strain thymoma development is regulated by a single autosomal susceptible gene, Tsr-1. At pre-thymoma age, BUF/Mna rats have extremely large thyrauses, when compared to those of other strains of rats. Genetic studies in crosses between BUF/Mna rats with large thymuses and WKY/NCrj rats with small thymuses suggested the presence of a major autosomal gene, Ten-1 , which contributes to thymus enlargement in a backcross population. Linkage studies between Ten-1 and microsatellite markers in backcross rats of (WKY/NCrj×BUF/Mna)Fl×BUF/Mna have led to the localization of Ten-1 in chromosome 1. This result may provide an approach to clone Tsr-1 , which could be allelic to Ten-1.  相似文献   
58.
A total of 518 bacterial strains isolated from the urine of patients with various urological diseases in our Urological Department between November, 1987 and February, 1989 were studied for their beta-lactamase production and susceptibility to various antimicrobial agents was determined. beta-lactamase activity was determined by the acidometry disc method. There were 241 gram-positive cocci, 276 of gram-negative rods and 1 Neisseria gonorrhoeae. Thirty-four percent of the gram positive and 76.3% of gram negative rods produced beta-lactamase. S. aureus (81.3%), S. epidermidis (65.1%) in gram-positive cocci, E. cloacae (100%), S. marcescens (100%), C. freundii (100%), P. aeruginosa (97.2%), P. Rettgeri (88.9%), E. gergoviae (85.7%), K. oxytoca (84.6%), M. morganii (81.8%) and E. coli (69.0%) in gram-negative rods produced beta-lactamase at a higher rate. beta-lactamase produced by gram-positive cocci was entirely penicillinase, and that produced by gram-negative rods only penicillinase in 4.0%, only cephalosporinase in 44.2% and both in 25.4%. In S. aureus and S. epidermidis, the isolated rate of strains resistant to ampicillin (p less than 0.01) and piperacillin (p less than 0.05) in the beta-lactamase producing strains was significantly higher than that in the beta-lactamase non-producing strains. In E. coli, the isolation rate of strains resistant to ampicillin and piperacillin in the penicillinase-producing strains was significantly higher than in the penicillinase non-producing strains (p less than 0.01). But both cephalosporinase-producing strains and beta-lactamase non-producing strains showed high susceptibility to cephalothin. These results suggest that the penicillinase might present a clinical problem in the treatment of urinary tract infections by S. aureus, S. epidermidis and E. coli.  相似文献   
59.
To clarify how the peripheral nerve adapts to elongation during gradual limb lengthening, electrophysiological and histomorphometric examinations were performed on the sciatic nerves in 18 rabbits. External fixators were used to lengthen the right femora by 30 mm (30%), at a daily rate of 0.5 mm (Group 1) or 2.0 mm (Group 2). Examinations were performed immediately after the limb lengthening procedure. Electrophysiologically, mild conduction slowing was observed in Group 1; a conduction block was evident in Group 2. Histologically, the mean diameter of myelinated fibers was unchanged in Group 1, but a significantly decreased diameter was observed in Group 2. Electron microscopy revealed that mild degenerative change of unmyelinated axons occurred sporadically in two cases in Group 2, but neither group showed evidence of thinning of myelin sheath of myelinated fibers. The mean internodal length (between nodes of Ranvier) of teased fibers was 1216+/-295 microm in the control contralateral side, 1484+/-347 microm in Group 1, and 1467+/-322 microm in Group 2. Thus the internodes were lengthened by 22.1% (Group 1) and 20.7% (Group 2) in comparison with those of the controls. Straightening of the geometry of paranodal myelin sheath was significantly correlated with the rate of distraction. These results indicate that myelinated nerve fibers adapt to gradual elongation by lengthening each Schwann cell body, not by proliferation of Schwann cells.  相似文献   
60.
A case of non-Hodgkin's lymphoma showed a phenotypic and genotypic cell lineage switch twice during nine years of his clinical history; first, T-cell type, pleomorphic small cell lymphoma developed, followed by B-cell type, diffuse centroblastic/centrocytic lymphoma, and finally T-zone lymphoma without follicles again developed, from which AST-1 cultured cell line was established. Karyotype analysis demonstrated a shared abnormal chromosome, der(1)t(1;?)(p36;?), among the first relapsed B-cell tumor, the second relapsed T-cell tumor and AST-1 cell line. Furthermore, T-cell receptor (TCR) γ gene rearrangement bands of the same size were observed in the first relapsed B-cell tumor and the second relapsed T-cell tumor as well as AST-1 cell line. These results suggested that both relapsed tumors of different cell lineages are derived from a common malignant clone, presumably a committed lymphoid stem cell. A unique translocation, t(2;14)(q37;q11.2), which may involve TCR δ/α gene complex, was observed in the second relapsed tumor and AST-1 cells. To attempt to isolate the breakpoint of this translocation, the configuration of TCR δ/α gene complex was studied. The result showed that two rearrangements of TCR α gene detected with Jα probes were the products of the normal TCR rearrangement process, and were not involved in the translocation at this region. This patient, together with the AST-1 cell line, provided us a unique opportunity to study the development and clonal evolution of malignant lymphoma.  相似文献   
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