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81.
We report a case of bladder hernia. A 68-year-old man was admitted to our hospital for the management of prostate cancer. An egg-sized soft mass was palpated at his right inguinal region. Magnetic resonance imaging and cystography revealed that the mass was a bladder hernia. During radical prostatectomy, we had to resect the bladder hernia for safe regional lymphadenectomy. This hernia was the extraperitoneal type. The stage of prostate cancer was pT3b N0 M0. This is the third reported case of inguinal bladder hernia associated with prostate cancer in Japan.  相似文献   
82.
A magnetic fluid (MF) for a rotary blood pump seal enables mechanical contact-free rotation of the shaft and, hence, has excellent durability. The performance of a MF seal, however, has been reported to decrease in liquids. We have developed a MF seal that has a "shield" mechanism and a new MF with a higher magnetization of 47.9 kA/m. The sealing performance of the MF seal installed in a rotary blood pump was studied. Under the condition of continuous flow, the MF seal remained in perfect condition against a pressure of 298 mm Hg (pump flow rate: 3.96 L/min). The seal was also perfect against a pressure of 170 mm Hg in a continuous flow of 3.9 L/min for 275 days. We have developed a MF seal that works in liquid against clinically used pressures. The MF seal is promising as a shaft seal for rotary blood pumps.  相似文献   
83.
84.
Purpose  The aim of this study was to evaluate the indications for pulmonary resection (lobectomy) in patients with increased total pulmonary vascular resistance (TPVR) during a preoperative unilateral pulmonary artery occlusion (UPAO) test. According to our previous report, the feasibility of performing lobectomy in patients with a high risk of cardiopulmonary complications is determined on the basis of the increase in TPVR after 15 min of obstruction during the UPAO test (occluded TPVR). Methods  A total of 19 high-risk [occluded TPVR ≥700 dynes/s/cm−5/m2 (dynes)] patients who underwent lobectomy or pneumonectomy were studied and a detailed analysis of postoperative cardiopulmonary complications was performed. The subjects were divided into four groups based on the occluded TPVR (700–799 dynes, 800–899 dynes, 900–999 dynes, or ≥1000 dynes) to compare the incidence of postoperative complications. Results  Two patients died after surgery. One of them had an occluded TPVR >1000 dynes and died 313 days after right upper lobectomy; the other had an occluded TPVR of 783 dynes and died 20 days after right pneumonectomy. Postoperative cardiopulmonary complications occurred in 6 of 19 patients (31.6%), and all three patients with an occluded TPVR ≥900 dynes developed cardiopulmonary complications. Conclusion  Limited surgery should be performed in patients with an occluded TPVR ≥900 dynes.  相似文献   
85.

Background

The purpose of this study was to assess changes in the three-dimensional (3D) load-bearing mechanical axis (LBMA) preoperatively and at 3 weeks and more than 1-year follow-up after total knee arthroplasty (TKA), and effects of the degree of constraint in the anteroposterior (AP) direction because of the retention of the posterior cruciate ligament (PCL) and the implant design on the changes in LBMA.

Methods

We evaluated 157 knees from 131 patients, including 79 knees that received meniscal-bearing-type (PCL-retaining) and 78 knees that received rotating-platform-type (PCL-substituting) prostheses. Quantitative 3D computed tomography was used to assess changes in the location of the pre- and postoperative LBMA at the tibial plateau level.

Results

Changes in the 3D axis were mainly found from medial to lateral and posterior to anterior in both implant designs with no significant differences. Change in the mediolateral (ML) direction was improved soon after TKA, but change in the AP direction improved more gradually over time. The different constraints in the AP direction because of the retention of the PCL and different implant designs did not affect the changes in the LBMA.

Conclusions

The LBMA in the AP direction more than 1 year postoperatively, as well as the LBMA in the ML direction at 3 weeks, appears to shift toward the location found in normal knees after TKA, regardless of the type of prosthetic constraint. These changes may be an important factor that influences the periarticular knee bone mineral density which load bearing may be related to.

Level of evidence

Level II, Prognostic study.
  相似文献   
86.
A 42-year-old woman was admitted to Kyushu University hospital because of 6 months' history of bilateral leg edema. Upon admission, ascites and pleural effusion as well as systemic edema were noted. Laboratory tests revealed hypoalbuminemia of 1.5 g/dl and massive proteinuria of 10 g/day. She was diagnosed with nephrotic syndrome. Renal biopsy revealed diffuse thickening of the glomerular basement membrane (GBM) and a crescent-like extracapillary lesion with segmental sclerosis in four of 11 glomeruli. Immunoglobulins and complements were negative by immunofluorescence examination. Therefore, we diagnosed this as focal segmental glomerulosclerosis (FSGS) rather than membranous nephropathy. Using an electron microscope, we observed a thickening of the GBM with numerous intramembranous vesicle-like microstructures and an infolding of the podocyte into the GBM. Since the microstructures were partly demarcated by a unit membrane and some of them were located very closely to the infolded podocyte, we speculated that the microstructures were derived from the podocyte. The unique electron microscopic finding of our case is a disease entity rather than a reactive phenomenon.  相似文献   
87.
Quality of life in patients with spinal osteoporosis is impaired by the decline of spinal mobility. However, the factors related to the spinal mobility in these patients are still unclear. We evaluated the possible factors affecting spinal mobility in patients with postmenopausal osteoporosis. A total of 128 postmenopausal women with osteoporosis aged over 50 years (mean, 70 years) were included in this study. The thoracic and lumbar kyphosis angles and range of motion (ROM) of the total spine were measured in the upright position and at maximum flexion/extension with a computer-assisted device. The paravertebral muscle thicknesses (PVMT) of thoracic and lumbar spine in the upright position were measured using an ultrasound unit. The number of vertebral fractures was evaluated with radiographs of the spine. Isometric back extensor strength (BES) was evaluated with a strain-gauge dynamometer. Correlations between these variables were then analyzed. Age ( r =–0.412), lumbar kyphosis angle ( r =–0.284), BES ( r =0.369), PVMT at the lumbar spine ( r =0.227) and the number of vertebral fractures ( r =–0.260) showed significant correlations with total spinal ROM ( P <0.05). However, no significant correlations were observed between the total spinal ROM and PVMT at the thoracic spine ( r =–0.069) or thoracic kyphosis angle ( r =–0.138). Multiple regression analysis revealed that the BES was the most significant contributor to the total spinal ROM. The present study suggests a possible association between BES and spinal mobility in patients with postmenopausal osteoporosis.  相似文献   
88.
The ligamentum flavum is considered to be one of the important causes of radiculopathy in lumbar degenerative disease. Although there have been several reports anatomically examining the positional relationship between the ligamentum flavum and nerve root, there are few reports on ventral observation. The purpose of this study is to clarify the shape of the ligamentum flavum seen ventrally, and to obtain anatomic findings related to nerve root compression. The subjects were 18 adult embalmed cadavers, with an average age of 78 years at the time of death. The ventral shapes of the ligamentum flavum were observed. The relationships between the morphological change of the ligamentum flavum and nerve root compression or radiographic findings were statistically evaluated. Among the shapes of the ligamentum flavum, bulging of the ligament was most frequently observed. Proximal bulging indicates the type with the cranial portion bulging from the subarticular zone to the foraminal zone of the ligamentum flavum. In this type associated with a decrease in disc height, nerve root compression was frequently observed. Thus, we could more realistically grasp the relationship between bulging morphology of the ligamentum flavum and nerve root compression.  相似文献   
89.
Objective Self-expandable metallic stent (EMS) placement has been the first choice for dysphagia because of the certainty over its safety, low invasiveness, and immediate efficacy. However, there still remain some problems in relation to the EMS placement site and anticancer therapies before and after EMS placement. Methods: Consecutive 78 patients in whom EMS was placed due to the unresectable malignant stricture in the esophagus or cardia from July 1995 to August 2003 in our department were studied. Results: Gastroesophageal reflux was found in 5 of 8 patients after placement of conventional EMS for the stricture in the gastroesophageal junction. Meanwhile, acid and bile reflux into the esophagus were not detected by pH and bilirubin monitoring, respectively, in 6 patients after placement of the EMS with an anti-reflux mechanism for the stricture in the gastroesophageal junction. The median survival period of all patients after EMS placement was 123 days. The median survival period of 7 patients with radiotherapy only after EMS placement was 138 days and that of 17 patients with radiotherapy before EMS placement was 60 days, which was shorter than that of the former (p<0.05). On the other hand, the median survival period after hospital admission due to dysphagia of these 7 patients was longer than that of 17 patients with radiotherapy only before EMS placement, although, the difference was not significant. Conclusion: EMS with an antireflux mechanism is not commercially available in Japan and approval is urgently required. The indication of radiotherapy associated with EMS placement is to be studied further.  相似文献   
90.
We report a case of renal hemangiopericytoma which was incidentally discovered by ultrasonography at a health screening. A 58-year-old man was admitted to our hospital for close examination of the renal tumor. Computed tomography revealed the left renal tumor, 60 x 50 mm in size, which was well enhanced with contrast medium. Magnetic resonance imaging revealed an isointensity mass (T1-weighted) and high-intensity mass (T2-weighted) at the left kidney. Radical nephrectomy was performed on suspicion of left renal cell carcinoma. Histopathological examination revealed renal hemangiopericytoma. The present case is the 7th in the Japanese literature.  相似文献   
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