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41.
A 2-month-old girl with a supratentorial primitive neuroectodermal tumor (PNET), which extended into the skull, is herein presented. The patient underwent total removal of the tumor and also received a course of postoperative chemotherapy. After a follow-up period of 12 months, the infant is alive without recurrence. Histologically, the tumor was composed of poorly differentiated neuroectodermal cells, and these neoplastic cells showed a mild immunohistochemical reaction for GFAP and synaptophysin, and a moderate reactivity for neuron specific enolase and vimentin. In addition, a moderate level of immunoreactivity for HBA71 antigen (p30/32M1C2), which is the product of the M1C2 gene and is found in peripheral PNETs but not in central PNETs, was noted in many neoplastic cells. Although this tumor was located intracranially, it may be classified as a peripheral PNET.  相似文献   
42.
OBJECTIVE: To predict accurate morbidity after lung resection using treadmill exercise test. METHODS: A total of 130 patients (108 men and 22 women, with mean age 67.1+/-11.4 years (range, 34-78 years)) of 1129 patients underwent standard lobectomy were performed both treadmill exercise test and spirometry preoperatively. We measured maximum oxygen uptake/body weight (VO2max/BW) and change in arterial blood oxygen pressure from rest to symptom-limited maximum loading (delta aPaO2) and calculated exercise-induced hypoxemia (delta PaO2/delta VO2/BW), and retrospectively compared these parameters for patients with and without complications. RESULTS: There were five patients with severe postoperative complications, including three requiring use of a respirator, two with home oxygen therapy. %Vital capacity, VC (%, 80.2+/-13.2 vs. 92.5+/-20.9, P=0.026), delta PaO2 (Torr, -29.3+/-4.3 vs. -13.2+/-10.8, P=0.0004), VO2max/BW (ml/min/kg, 16.5+/-2.9 vs. 20.6+/-5.1, P=0.018) and delta PaO2/delta VO2/BW (Torr/ml/min/kg, -1.98+/-0.26 vs. -0.57+/-0.47) were significantly associated with worse outcome. All the five patients with complications had delta PaO2/delta VO2/BW<-1.7. CONCLUSIONS: Treadmill exercise testing is a good method for assessment of cardiopulmonary reserve. Limited resection must be performed if delta PaO2/delta VO2/BW is under -1.7.  相似文献   
43.
Purpose  The number of anesthesiologists per population in Japan is small compared with that in Europe and North America. While there is a growing concern that hard work causes anesthesiologists’ fatigue and may compromise patient safety, the workload and physical stress, as well as the impact of staff support on physicians’ stress have not been assessed in detail. The goal of this study was to evaluate the working environment, anesthesia workload, and occupational stress of anesthesiologists in Japan. Methods  A questionnaire survey was performed targeting 1010 members of the Japanese Society of Anesthesiologists working as anesthesiologists affiliated with acute care hospitals in Japan. Data on background information, working environment, operation anesthesia duties, and stress were collected, and the relationship of work stress with background, environment, and anesthesia duties was evaluated by linear regression analysis. Results  Responses were obtained from 383 full-time anesthesiologists (response rate, 43.9%). The total anesthesia time per week was 23.6 h on average. The work stress score was 114.3 ± 30.2 (mean ± SD) when the average workers’ work stress score in Japan was 100. The work stress score was significantly associated with “years of experience” (with experience < 10 years considered as the reference; 10–19 years: β = −0.18, P = 0.02, ≥20 years: β = −0.15, P = 0.04), “hospital with ≥500 beds” (with a hospital with ≤ 299 beds considered as the reference; β = 0.15, P = 0.04), “total time of anesthesia per week” (β = 0.18, P.02), “estimated annual cases managed by an anesthesiologist” (β = 0.12, P = 0.04) and “no-support stress” (β = 0.21, P < 0.01) on linear regression analysis (R2 = 0.12). Conclusion  Our results provide a quantitative assessment of the duties of anesthesiologists and show that work stress among anesthesiologists is related to workload and other factors. Summaries of this study were presented at the 53rd and 54th General Meetings of the Japanese Society of Anesthesiologists (JSA) at Kobe (2006) and Sapporo (2007).  相似文献   
44.

Objective

To determine the optimal accumulation time for three-dimensional positron emission tomography (3D-PET) with 18F-2-fluoro-2-deoxy-d-glucose (18F-FDG) to detect the brain uptake pattern typical of Alzheimer’s disease (AD).

Methods

Patients with mild AD or amnestic mild cognitive impairment (MCI) and normal control subjects were recruited in the Japanese Alzheimer’s disease neuroimaging initiative and examined with a PET scan during the 30–60 min after FDG injection. Three independent blinded experts interpreted the 30- to 60-min sum images, and images of patients with AD and MCI presenting AD patterns and normal subjects presenting normal patterns were used in the analysis. Early-scan (ES) and late-scan (LS) images were obtained from the data acquired at 30–35 min and 55–60 min after the injection, respectively. Separate target regions of interest (ROI) for ES and LS were defined as areas of significant reductions in the posterior cingulate and parietotemporal lobe in both hemispheres from the results of an initial cohort with 21 patients (AD 16, MCI 5) and 19 controls. A subsequent sample of 36 (AD 9, MCI 27) patients and 38 controls were used to compare the diagnostic capability of ES and LS using Z scores within the target ROI in individual statistical parametric mapping analysis.

Results

Compared to LS, ES showed lower activity in the frontal lobes and higher activity in the venous sinus than LS; however, the diagnostic capability of ES and LS did not significantly differ (sensitivity 0.97 and 0.97, specificity 0.82 and 0.84, area under the receiver-operating characteristic curve 0.96 and 0.97, respectively).

Conclusions

For a qualitative diagnosis of the AD pattern in 3D FDG-PET, results of ES were equivalent to those of LS. ES may be an option to shorten the entire PET procedure time, particularly in diagnosing early stages of AD.  相似文献   
45.
To evaluate the usefulness of assessing bone components using magnetic resonance imaging (MRI), the contributions of bone components, including mineral, fat and collagen, to bone mineral density (BMD) and T1 relaxation time (T1) were studied using phantoms. Excised human vertebrae were also evaluated by quantitative computed tomography (QCT) and MRI. T1 was shortened with increasing quantities of fat and collagen. In water, T1 was significantly affected by bone density, while in oil, T1 became slightly longer as bone density increased. The presence of fat and collagen caused under- and overestimations of BMD, respectively. There was good correlation between T1 and BMD in osteoporotic vertebrae and the vertebrae with long T1 showed an increased content of hematopoietic marrow and/or abnormally increased bone mineral. It was concluded that the experimental data showed that MRI can contribute to the assessment of bone quality.  相似文献   
46.
BACKGROUND: One of the crucial events in lupus nephritis is the glomerular deposition of immunoglobulins (Igs), of which pathogenic properties have been proposed mostly to be either type IIor type III allergic reactions. Some of IgG3-producing hybridoma clones established from an MRL/MpTn-gld/gld (MRL/gld) lupus mouse generate wire loop-like lesions in glomeruli resembling lupus nephritis when injected into SCID mice. These clones are useful for analyzing the mechanisms of glomerular deposition of antibodies in lupus nephritis at the monoclonal level. METHODS: Glomerular lesions of SCID mice injected with the hybridoma clones, 17H8a or 1G3 as control were analyzed by light and electron microscopy. Interaction of the antibodies with human glomerular endothelial cells (HGECs) and human umbilical vein endothelial cells (HUVECs) in vitro was studied by fluorescence microscopy, electron microscopy, and flow cytometry. RESULTS: Both antibodies did not show any antigen specificity for mouse glomeruli. The glomerular lesions generated by 17H8a, but not by 1G3, contained electron-dense deposits not only in subendothelial regions but also in the cytoplasm of endothelial cells, suggesting internalization of the 17H8a antibodies by endothelial cells. In cell culture studies, internalization of only 17H8a antibodies by HGECs and HUVECs was observed, but the antibodies did not have antigen specificity for both types of endothelial cells. The internalization by HUVECs was mediated by actin polymerization, and it was inhibited by RGDS (Arg-Gly-Asp-Ser) tetrapeptide, antihuman fibronectin and antihuman integrin beta1 monoclonal antibodies. CONCLUSION: The interaction between particular antibodies and endothelial cell surface integrins via fibronectin may be involved in their subsequent internalization by endothelial cells leading to antibody deposition in glomeruli. This may be one of the mechanisms of glomerular injury in lupus nephritis.  相似文献   
47.
The clinical and pathological features of metastatic prostate cancer with normal level of serum prostate-specific antigen (PSA) were investigated. Four patients with metastatic prostate cancer had serum PSA within the normal range at the diagnosis. All tumors were poorly-differentiated adenocarcinoma. Endocrine therapy was performed as the initial therapy in all patients. Despite subsequently treatment, all cases died of prostate cancer at 2, 8, 9 and 38 months. During disease progression, 3 of 4 patients had elevated serum markers such as carcinoembryonic antigen (CEA), CA19-9, CA15-3, CA125, neuron-specific enolase and pro-gastrin releasing peptide. Immunohistochemical examination of the initial biopsy specimens revealed that 4 and 3 cases were positive for CEA and chromogranin A, respectively. In advanced prostate cancer patients with low PSA level, those markers may aid in the follow up of disease.  相似文献   
48.
We report a case of a 33-year old man who presented with symptoms and signs of an acute biliary tract obstruction with jaundice and abdominal pain. Diagnostic imaging studies revealed a biliary stricture of the hepatic confluence, and a mass at the hepatic hilum which obstructed the extrahepatic bile duct from the outside. At laparotomy, there was 3-cm-size nodule at the hilum which presented with a rubbery consistency. We performed extrahepatic bile duct resection and right and left hepaticojejunostomy. Histological examination of the resected specimen revealed follicular lymphoma, which consisted of medium cleaved follicle-like cells, grade 1 of 3 according to the revised European-American classification of lymphoid neoplasms proposed by International Lymphoma Study Group. Postoperative follow-up of more than 1 year has been completely uneventful, without any symptoms or signs of disease recurrence. This is the second case report of follicular lymphoma of the extrahepatic bile duct.  相似文献   
49.
OBJECTIVE: There is no criterion for the timing of surgical resection of pulmonary metastasis. In this study, we investigated the optimal period for pulmonary metastasectomy. METHODS: Between 2000 and 2005, 68 patients underwent complete pulmonary resection of metastatic cancer. Clinical prognostic factor in multivariate analysis was examined. RESULTS: The interval from pulmonary metastasectomy until subsequent recurrence and the interval from detection of pulmonary metastasis until pulmonary metastasectomy were independent prognostic factors. To investigate the relationship between the two characteristics, the 68 patients were divided into two groups according to the interval from lung metastasectomy until subsequent recurrence. Nineteen patients relapsed within 1 year after pulmonary metastasectomy (group A), while 49 patients did not relapse within 1 year (group B). The interval from detection of pulmonary metastasis until pulmonary metastasectomy was significantly shorter in group A than in group B (2.9 months vs 7.1 months, p=0.01). Based on these results, we divided the patients into two different groups and survival was compared. Significantly shorter survival was observed in the patients who underwent pulmonary metastasectomy within 3 months after detection of pulmonary metastasis (group X, n=35) than in those who underwent the surgery beyond 3 months (group Y, n=33). CONCLUSIONS: There were many cases of early relapse after metastasectomy when the interval from detection of pulmonary metastasis until pulmonary metastasectomy was short. Performing metastasectomy at least three months after detection of pulmonary metastasis may significantly improve the prognosis of patients.  相似文献   
50.
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