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71.
The authors report two cases of patients with lumbar ossification of the posterior longitudinal ligament (OPLL). One patient underwent surgery via the single posterior approach, and the other patient underwent combined anterior-posterior surgery. The authors consider the anterior approach for excision of the ossified lesion to be the most reasonable for treatment of lumbar OPLL. It is extremely important, however, to select the surgical procedure according to the individual patient's condition.  相似文献   
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73.
Encapsulated hepatocyte transplantation is a promising approach to cell transplantation without immunosuppression as an alternative to whole organ liver transplantation. However, the shortage of donor cells for hepatocyte transplantation has not been resolved, and at this critical point, it seems necessary to establish a method of hepatocyte cryopreservation to allow clinical application of hepatocyte transplantation and the development of a bioartificial liver system in the near future. In this study we demonstrated that cryopreserved microencapsulated rat and human hepatocytes can retain their hepatic function and that cryopreserved microencapsulated human hepatocytes transplanted into rat spleen remain viable without immunosuppression. Rat and human hepatocytes were isolated by a collagenase digestion method, and they were microencapsulated with poly-L-lysine. The microencapsulated rat hepatocytes were transferred to culture medium (DMEM containing 10% FBS and 10% DMSO) and immediately frozen in liquid nitrogen. A warm water bath (37 degrees C) was used to thaw the microencapsulated hepatocytes. Hepatic function, drug metabolism, and cell morphology were assessed after 90 days of cryopreservation. After 1 week of cryopreservation, microencapsulated hepatocytes were cultured for up to 2 weeks to assess their hepatic function and morphology. The morphology of human hepatocytes was assessed after 30 days of cryopreservation. Cryopreserved human hepatocytes were transplanted into rat spleen to assess their morphology. Cryopreserved microencapsulated hepatocytes retained their viability and were strongly positive for expression of albumin, OAT2, CYP3A2, and CYP3A9. Two weeks after cultivation, the cryopreserved microencapsulated rat hepatocytes had retained their hepatic function (urea synthesis). Cryopreserved microencapsulated human hepatocytes also mainly survived and retained their hepatic function for at least 30 days after cryopreservation. Moreover, entrapped cryopreserved human hepatocytes also survived and expressed albumin in rat spleen after transplantation. We demonstrated a novel method of long-term cryopreservation of rat and human hepatocytes by using an encapsulation technique, with retention of biological activity and excellent survival of the cryopreserved microencapsulated human hepatocytes transplanted into rat spleen. We believe that this novel approach to hepatocytes cryopreservation provides a new direction in encapsulated cell therapy with the goal of clinical application in the near future.  相似文献   
74.
To address the current role of liver transplantation (LT) for urea cycle disorders (UCDs), we reviewed the worldwide English literature on the outcomes of LT for UCD as well as 13 of our own cases of living donor liver transplantation (LDLT) for UCD. The total number of cases was 51, including our 13 cases. The overall cumulative patient survival rate is presumed to be more than 90% at 5 years. Most of the surviving patients under consideration are currently doing well with satisfactory quality of life. One advantage of LDLT over deceased donor liver transplantation (DDLT) is the opportunity to schedule surgery, which beneficially affects neurological consequences. Auxiliary partial orthotopic liver transplantation (APOLT) is no longer considered significant for the establishment of gene therapies or hepatocyte transplantation but plays a significant role in improving living liver donor safety; this is achieved by reducing the extent of the hepatectomy, which avoids right liver donation. Employing heterozygous carriers of the UCDs as donors in LDLT was generally acceptable. However, male hemizygotes with ornithine transcarbamylase deficiency (OTCD) must be excluded from donor candidacy because of the potential risk of sudden-onset fatal hyperammonemia. Given this possibility as well as the necessity of identifying heterozygotes for other disorders, enzymatic and/or genetic assays of the liver tissues in cases of UCDs are essential to elucidate the impact of using heterozygous carrier donors on the risk or safety of LDLT donor-recipient pairs. In conclusion, LT should be considered to be the definitive treatment for UCDs at this stage, although some issues remain unresolved.  相似文献   
75.
Unsuspected gallbladder carcinoma after laparoscopic cholecystectomy   总被引:5,自引:0,他引:5  
Background/Purpose Many cases have been reported of disastrous port-site recurrence after laparoscopic cholecystectomy (LC) revealed unsuspected gallbladder carcinoma (GBC). Some investigators have reported that the prognosis of patients after LC showed unsuspected GBC is not worsened by laparoscopic procedures. We retrospectively reviewed our cases and the literature to reconfirm the intrinsic risks of LC for unsuspected GBC. Methods Of 1663 patients who underwent LC from January 1991 to December 2003 in a single institution, 9 (0.54%) with unsuspected GBC were reviewed. Results These 9 patients consisted of 5 men and 4 women, whose ages ranged from 58 to 87 years, with a median age of 73 years. Two patients with a pT1a tumor (limited to mucosa) and 2 patients with a pT1b tumor (muscle layer) underwent no further operation. The remaining 5 patients with a pT2 tumor (subserosa) underwent further operations with lymph node dissection. Five patients (2 patients with pT1b and 3 patients with pT2) developed recurrence and all of them died within a median period of 19 months (range 14–37 months) after LC. The causes of death were bone metastases in 1 patient (pT2), local recurrence in 2 patients (pT1b and pT2), and peritoneal metastasis in 2 patients (one elderly patient with pT1b who underwent laparoscopic common bile duct exploration, and one patient with pT2 in whom the cystic duct was damaged during surgery). Four patients (2 with pT1 and 2 with pT2) have been doing well with a median follow-up of 39.5 months (range 12–99 months) after LC. Conclusions Surgeons should always prevent bile spillage during LC and when removing the resected gallbladder. When laparoscopic common bile duct exploration is planned, especially for elderly women, surgeons should also bear in mind the increasing possibility of unsuspected GBC.  相似文献   
76.
We report a case of cerebellar tuberculoma presenting with headache, without any specific data. A 22-year-old male had headache for recent three months. Because of detection of the tubercle bacillus in his sputum, he was suspected the pulmonary tuberculosis and the tuberculous meningitis. On admission the cerebrospinal fluid revealed no abnormal data and the tubercle bacillus was not detected in the culture. We started medication for the tuberculosis. MRI demonstrated a mass lesion at the right cerebellum, suggesting the presence of a tuberculoma. He underwent total removal of the tumor via the supracerebellar route. Histological examination revealed tuberculoma when there are no abnormal data. The intracranial tuberculoma may be confused with an intracranial neoplasm. It is important to make an overall evaluation to diagnose tuberculosis; for instance, compromised high age, HIV, and the type of steroid administered, will increase intracranial tuberculoma. In this report, we describe a cerebellar tuberculoma without any abnormal data, suggesting that intracranial tuberculoma should be considered in the differential diagnosis of any intracranial mass lesion.  相似文献   
77.
Rhabdomyolysis results from a variety of causes. We experienced 6 cases of rhabdomyolysis induced by dehydration in psychoneurosis patients or seniors. We should know dehydration as a risk factor for rhabdomyolysis especially in psychoneurosis patients or seniors.  相似文献   
78.
Anti-CD20 antibody (rituximab) is recently being used as a B cell-depleting agent in renal transplantation (RTx). However, the incidence of infectious complications associated with rituximab therapy remains uncertain. We evaluated the incidence of cytomegalovirus (CMV) infection associated with rituximab therapy in RTx. A total of 83 patients were enrolled. The immunosuppressive regimen consisted of tacrolimus or cyclosporin, mycophenolate mofetil, methylprednisolone and basiliximab. In 54 patients, only one dose of rituximab (200 or 500 mg/kg body weight) was given before RTx. A total of 25 of 43 (58.1%) recipients who were CMV seropositive prior to RTx and who received rituximab induction therapy developed CMV infection, compared to 18 of 24 (75%) CMV seropositive recipients who did not receive rituximab therapy ( P  = 0.1676). A total of 8 of 11 patients who were CMV seronegative prior to RTx and who received rituximab developed CMV infection. However, CMV seroconversion was seen in all 8 of these infected patients. Low-dose rituximab induction therapy in renal transplant recipients appears to have no influence on the incidence of CMV infection and CMV seroconversion. However, we have to consider anti-CMV prophylaxis therapy, because of high incidents of CMV infection, especially for CMV seronegative recipients who received rituximab.  相似文献   
79.
Background  Simultaneous bilateral total hip arthroplasty (THA) can offer a potential benefit of greater postoperative hip motion without the negative influence of contralateral hip disabilities, compared to two-stage THA. However, postoperative changes in hip motion after simultaneous bilateral THA have rarely been reported. The purpose of this study was to clarify the efficacy of simultaneous procedures on postoperative hip motion and functional recovery. Methods  We retrospectively compared hip motion in 27 patients treated with simultaneous bilateral THA to those in 11 patients with two-stage bilateral THA, 35 patients with unilateral THA for unilateral disease, and 15 patients with unilateral THA for bilateral disease. We also evaluated the clinical manifestations according to the Japanese Orthopaedic Association (JOA) hip scores and compared the outcomes among the groups. All of the THA surgeries were primarily performed through a posterolateral approach using cement-less prostheses. The diagnosis at surgery was dysplastic osteoarthritis in all patients, and the patients were followed up for at least 4 years. Results  The postoperative improvement of motion in hip flexion was significantly greater in patients treated with simultaneous procedures compared to patients with two-stage THA and unilateral THA for bilateral disease. The differences in improvement of motion in hip abduction were less marked than the improvement in hip flexion among the groups. Although there were no significant differences in pain scores among the groups, the values for activity of daily living were significantly greater in patients treated with simultaneous bilateral THA and patients with unilateral THA for unilateral disease than in patients with unilateral and two-stage bilateral THA for bilateral disease. Conclusions  The simultaneous procedure was considered to be more effective in patients with bilateral hip osteoarthritis and demonstrated a substantial improvement in hip motion and functional recovery after THA.  相似文献   
80.
Purpose  We have been developing a computer-aided detection (CAD) system for lung nodules on multidetector row computed tomography (MDCT). The scheme for nodule detection in this system is featured by three-dimensional analysis for nodule detection in nodules and their surroundings, which is designed to discriminate nodules from blood vessels. The purpose of this study was to evaluate the CAD system. Materials and methods  MDCT images from 30 patients with lung nodules were read twice, 3 weeks apart by a chest radiologist to detect noncalcified nodules of ≥4 mm. The first reading was without CAD, and the second reading was with CAD. Based on the reference standard later determined by another chest radiologist, the sensitivity of the former chest radiologist without or with CAD was obtained; the sensitivity and false-positive rate of the system alone were also obtained. Results  The reference standard consisted of 66 nodules. The sensitivity of the chest radiologist was 77% (51/66) without CAD and 91% (60/66) with CAD, showing a significant improvement. The CAD system alone showed a sensitivity of 79% (52/66) with the false-positive rate of 4.5 per patient. Conclusion  Although preliminary, these results indicate the efficacy of the CAD system.  相似文献   
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