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71.
Selective loss of dopaminergic neurons is the final common pathway in Parkinson's disease. Expression of Parkin associated endothelin-receptor like receptor (Pael-R) in mouse brain was achieved by injecting adenoviral vectors carrying a modified neuron-specific promoter and Cre recombinase into the striatum. Upregulation of Pael-R in the substantia nigra pars compacta of mice by retrograde infection induced endoplasmic reticulum (ER) stress leads to death of dopaminergic neurons. The role of ER stress in dopaminergic neuronal vulnerability was highlighted by their decreased survival in mice deficient in the ubiquitin-protein ligase Parkin and the ER chaperone ORP150 (150 kDa oxygen-regulated protein). Dopamine-related toxicity was also a key factor, as a dopamine synthesis inhibitor blocked neuronal death in parkin null mice. These data suggest a model in which ER- and dopamine-related stress are major contributors to decreased viability of dopaminergic neurons in a setting relevant to Parkinson's disease.  相似文献   
72.
In acetabular dysplasia of the hip joint accompanied by a giant acetabular bone cyst, rotational acetabular osteotomy may cause serious complications, such as bone necrosis after surgery or fracture of the fragile acetabulum during the operation. In a patient with this condition, we performed a two-stage operation: first, autogenous bone grafting supplemented with hydroxyapatite filling, then rotational acetabular osteotomy (after new bone formation had been assured). Radiographs and CT scans showed favorable fusion of the grafted bone. Some 18 months after the second operation, arthrograms showed no inflow of contrast medium from the articular cavity into the bone cyst region, although this had been observed before treatment. Thus, an effective remodeling of bony congruency was indicated in the mobile acetabulum 5 years after the second operation. This two-stage operation appears to be useful for correcting acetabular dysplasia accompanied by a giant bone cyst and to carry a reduced risk of serious complications, such as deterioration of the articular surface of the acetabulum or necrosis of the translocated acetabulum.  相似文献   
73.
Diffusion-weighted MRI of subdural and epidural empyemas   总被引:1,自引:0,他引:1  
We reviewed diffusion-weighted images (DWI) from eight patients with subdural and four with epidural empyemas to assess the possibility of differentiating between these lesions by DWI. The signal intensities of the empyemas on DWI, and maps of the apparent diffusion coefficient (ADC) were analysed in seven patients. In seven of the eight patients with subdural empyema, the lesions appeared as areas of high signal. The ADC maps confirmed that these areas were the result of restricted diffusion. (In the remaining patient, the lesion showed a mixture of high and low signal.) The epidural empyemas contained areas of low signal in all four patients; part of the empyema was isointense or gave high signal in two. DWI may be an adjunct to conventional sequences for differentiating between subdural and epidural empyemas.  相似文献   
74.
Interleukin-6 (IL-6) and interleukin-11 (IL-11) are known to influence osteoclast formation and bone resorption. In order to determine whether IL-6 and IL-11 could independently support human osteoclast formation, these factors were added to cultures of human peripheral blood mononuclear cells of the monocyte (CD14(+)) fraction in the presence of macrophage colony-stimulating factor (M-CSF). Under these conditions, IL-6 and IL-11 induced the formation of multinucleated cells which were positive for TRAP, VNR, and calcitonin receptor and capable of lacunar resorption. Osteoclastogenesis induced by IL-6 and IL-11 was inhibited by the addition of an anti-gp130 antibody but not by osteoprotegerin. These results indicate that IL-6 and IL-11, which are thought to play a role in several osteolytic bone disorders, are directly capable of inducing osteoclast formation by a RANKL-independent mechanism.  相似文献   
75.
A 28-year-old man presented with progressive mental deterioration. Thirteen years earlier he had undergone radiation therapy for a pineal germinoma. Neuroimaging showed a homogeneously enhanced mass lesion along the ventricular wall. The cerebrospinal fluid (CSF) level of human chorionic gonadotropin (HCG) was high. Endoscopic biopsy revealed that the tumor was a two-cell pattern germinoma. The diagnosis was germinoma with syncytiotrophoblastic giant cells (STGC). He first received three cycles of chemotherapy with carboplatin and etoposide and then two cycles with ifosfamide, cisplatin, and etoposide. Subsequently, the tumor size decreased markedly and the CSF level of HCG returned to normal. However, he died 22 months after the recurrence. Histological verification and measurement of tumor markers are necessary for the optimum treatment of germ cell tumors. Adequate initial chemotherapy and long-term follow up are essential for patients with germinoma with STGC.  相似文献   
76.
Streptococcal esterase is known as one of the extracellular products of Group A streptococci. In this paper, an antibody of streptococcal esterase titers in patients with rheumatic fever, acute glomerulonephritis and other streptococcal infections were determined. In cases with acute rheumatic fever and acute glomerulonephritis, ASE titers showed almost the same changes as ASO, ASK and ADN-B. The characteristics of the ASE determination, however, is that small changes in the titers could be detected because the final definition of this titer was determined by photometer.  相似文献   
77.
78.
Objectives: Upper gastrointestinal bleeding, particularly from a stress-induced duodenal ulcer, is an extremely important perioperative complication in cardiovascular surgery. Methods: In the present study, 33 patients undergoing elective open heart surgery between July 2000 and February 2001 were allocated to either a famotidine (FAM) or rabeprazole (RPZ) group to examine the perioperative gastric and esophageal pH readings, in conjunction with an investigation into the effect of infection with Helicobacter pylori (HP). Results: Postoperative upper gastrointestinal bleeding did not occur in either group, and the intraoperative and postoperative mean gastric pH readings, as well as the holding time pH> 6, suggested sufficient acid suppression by either drug. Gastric acid secretion was less strongly suppressed in HP-negative patients in the FAM group, but was unaffected by HP infection status in the RPZ group. Conclusion: The FAM group and RPZ group revealed a sufficient effect of gastric acid suppression. It was indicated that FAM had an insufficient effect of gastric acid suppression for HP-negative patients.  相似文献   
79.
The purpose of this study was to determine whether body mass index (BMI) influences the clinical outcomes and overall cost of transplantation in adult liver transplantation (OLT) using records of 700 adult OLT recipients. Patients were divided into BMI range groups over the range of 15 to 42 (mean = 26.7), namely: <25, n = 288 (41%); 25 to 30, n = 245 (35%); > or =30, n = 167 (24%). Only a small subset of this last group was morbidly obese (BMI > or = 35, n = 37, 5% of total). We did not detect an effect of BMI on patient or graft survival, the incidence of acute graft rejection, or major surgical complications. BMI was not related to length of hospital stay. There were no statistical differences between the three groups with respect to the ratio of overall hospital cost in a general linear model, corrected for age, gender, calculated Model for End-Stage Liver Disease score, retransplant status, or return to the operating room. In conclusion, obesity did not influence either the costs or the clinical outcomes following OLT. Further analysis of the morbidly obese population with respect to cost and outcome is warranted.  相似文献   
80.
We have reported that the apparent diffusion coefficient (ADC) was correlated with bone mineral density, but the relation between the restricted diffusion of the water molecules and the trabecular bone structure was unclear. The purpose of our study is to clarify this relationship using two component analyses with an original phantom. With an increase in the interspace area of the simulated trabecular bone, the ADC of the fast component was increased, and the fraction of the fast component was also increased. On the other hand, with an increase in the interspace area of the simulated trabecular bone, the ADC of the slow component was decreased, and the fraction of the slow component was increased. Moreover, the ADC and fraction of the dry vertebral bone agreed with those of the simulated trabecular bone. This result means that our phantoms can reproduce the actual trabecular bone structure, which induces the restricted diffusion. The diffusion of the water molecules was separated into fast and slow components because of the restricted diffusion of the trabecular bone structure. Our original phantom enables analyzing restricted diffusion, and this analytical method obtains more detailed information on trabecular bone structure.  相似文献   
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