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71.
In the present study we investigate whether alterations of sleep propensity or of wake propensity are implicated in sleep initiation disturbances encountered in major depressive insomnia and in primary insomnia. For this purpose, the time course of electroencephalogram (EEG) power density during the period preceding sleep onset and during the first non-rapid eye movement (REM) period was examined in three age and gender matched groups of 10 women and 11 men (healthy controls, primary insomniacs and depressive insomniacs). In contrast to healthy controls and depressive insomniacs, patients with primary insomnia did not experience a gradual decrease of their alpha and beta1 power during the sleep onset period and had a lower delta activity in the 5 min preceding sleep onset. Compared with the two other groups, depressive patients exhibit less dynamic changes in slow wave activity during the first non-REM period. The present results suggest that hyperarousal (high 'Process W') may mainly be implicated in the sleep initiation difficulties of primary insomniacs whereas the homeostatic sleep regulation process seems to be partially maintained. In our major depressed patients, the sleep initiation disturbances appeared to relate to a lower sleep pressure (low 'Process S') rather than to hyperarousal. This study supports the idea that different mechanisms are implicated in sleep disturbances experienced by primary insomniacs and major depressive insomniacs.  相似文献   
72.
Abstract Survival time of 73 patients with undiagnosed gallbladder carcinoma incidentally found after cholecystectomy treated between 1982 and 2000 was evaluated in relation to various variables, with special reference to the significance of the radical second resection. The most significant prognostic factor was the depth of tumor invasion as assessed by univariate and multivariate analyses (odds ratio 3.40, 95% CI 1.65–7.00, p < 0.001). None of the 23 pT1 patients received radical second resection, and all of them were doing well without recurrence at their last follow-up examination. The 3-year survival rate was 68% for patients with pT2 and 14% for patients with pT3. Patient characteristics for the 18 pT2 patients who underwent radical second resection were similar to the characteristics of the 25 pT2 patients who did not; nor did postoperative survival times differ significantly. Survival time was not correlated with the interval from initial to second surgery or the type of initial cholecystectomy (open vs laparoscopic). In 11 patients with pT2 whose surgical margin was judged positive at initial cholecystectomy, the radical second resection significantly lengthened survival time. Radical second resection tended to prolong the median survival period from 7 to 15 months in 7 patients with pT3, although the difference was not significant. In conclusion, patients with pT1 undiagnosed carcinoma need no further treatment. The redo surgery was found to prolong survival only in patients with pT2 with positive surgical margin at initial cholecystectomy. Electronic Publication  相似文献   
73.
A 58-year-old man with a 15-year history of idiopathic pulmonary fibrosis was hospitalized for rapid progression of muscle weakness to bilateral foot drop. Although laboratory data revealed high titers of myeloperoxidase anti-neutrophil cytoplasmic antibody (489 EU), the patient was diagnosed as polyarteritis nodosa limited to the lower portions of the legs. Despite of the treatment with large doses of corticosteroids and cyclosporin A, his symptoms barely improved during the following two months.  相似文献   
74.
This study was conducted to assess the diagnostic potential and pitfalls of performing fine-needle aspiration cytology (FNAC) for thyroid nodules. We retrospectively analyzed 1012 aspirated samples obtained from 806 thyroid nodules by the ultrasound (US)-guided method. Of these 806 nodules, 226 (31%) had been surgically treated, 152 (67%) of which were histologically diagnosed as malignant. The rate of sufficient aspirate was 82%, being lower in nodules with a diameter of less than 5 mm (73%, P = 0.10); either calcified (77%, P = 0.043) or benign (72%, P = 0.0002). The accuracy of FNAC was 75%, the rate of indeterminate diagnosis was 16%, the false negative rate was 13%, and the positive malignancy rate was 99%. The rate of indeterminate diagnosis was higher in adenomatous goiter, follicular carcinoma, and malignant lymphoma, at P = 0.015, P = 0.0008, and P = 0.035, respectively. The accuracy was lower in follicular carcinoma and malignant lymphoma (both at P = 0.013). Sufficient aspirate was finally obtained from 701 (87%) of the 806 nodules by repeated aspiration. Of 152 malignant nodules, 28 (18%) were diagnosed after two or more aspirations, and the accuracy was improved to 81% by repeating the procedure. These findings indicated that repeated aspiration may be a simple and effective method of improving the diagnostic potential of FNAC. Received: November 1, 1999 / Accepted: September 26, 2000  相似文献   
75.
The purpose of this study was to determine whether intratumor expression of platelet-derived endothelial cell growth factor (PD-ECGF) is a prognostic factor. We examined specimens from 61 cases of carcinoma of uterine cervix (Ca-Cx). Specimens were stained with periodic acid-Schiff preparation with diastase (d-PAS) and alcian blue (pH 2.5) to identify the presence of intracellular mucin. PD-ECGF expression and microvessel count (MVC) were assessed by immunohistochemical staining. Twenty specimens stained positive for mucin. MVC correlated with clinical stage (p<0.01). There was a correlation between PD-ECGF expression and survival time (p<0.05), but no correlation was seen between mucin staining positivity, MVC, and PD-ECGF expression and survival time by the Cox proportional hazard model. Intratumor PD-ECGF expression was not a prognostic factor in keratinizing-type squamous cell carcinoma of the uterine cervix.  相似文献   
76.
Adenoid cystic carcinoma (ACC) of the uterine cervix is extremely rare, frequently metastasizes to distant organs, and its prognosis is poorer than squamous cell carcinoma of the uterine cervix. The reasons for its poor prognosis are unclear. This case had both an ACC and a carcinoma in situ (CIS) of the uterine cervix, so the expressions of CD34, vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) were investigated in both tumors. Hysterectomy was performed on a 76-year old woman and the uterine cervical tissues immunohistochemically analyzed. Expressions of CD34 were positive in the ACC lesions but negative in the CIS ones and angiogenesis was confirmed in ACCs. Furthermore, expressions of VEGF and COX-2 were shown in ACC, but were absent in CIS. In conclusion, the expression of COX-2 in ACC may induce the expression of VEGF, increase angiogenesis and enhance tumor growth and invasion.  相似文献   
77.
78.
Background: Our purpose was to evaluate the effectiveness of a newly developed non‐invasive traction technique known as thin endoscope‐assisted endoscopic submucosal dissection (TEA‐ESD) procedure for the removal of colorectal laterally spreading tumors (LST). Patients and Methods: A total of 37 LST located in the rectum and distal sigmoid colons of 37 patients were eligible for outcome analysis. Twenty‐one LST were treated with TEA‐ESD and were then retrospectively compared to 16 LST that had previously been treated with standard ESD. Tumor size, en bloc resection rate, procedure time, combined number of different electrical surgical knives used during each procedure and associated complications were evaluated in this case–control study. Results: There was no statistically significant difference in tumor size between the TEA‐ESD group and the ESD control group (43.6 ± 16 mm and 42.4 ± 14 mm, respectively). All LST were successfully resected en bloc in both groups. Procedure duration was shorter for the TEA‐ESD group than the ESD control group, although the difference was not statistically significant (96 ± 53 minutes vs 116 ± 74 minutes; P = 0.18). The percentage of cases in which only one electrical surgical knife was used during the entire procedure was significantly higher in the TEA‐ESD group compared to the ESD control group (85.7% vs 31.3%; P = 0.0005). There were no perforations in the TEA‐ESD group while the ESD control group experienced one perforation. At the present time, TEA‐ESD is limited to the rectum and distal sigmoid colon. Conclusion: It was technically easier, safer and more cost‐effective to perform ESD for LST in the rectum and the distal sigmoid colon using the newly developed TEA‐ESD traction technique.  相似文献   
79.
80.
We assessed the capability of MR imaging to demonstrate the details of hepatoduodenal ligament consisting of portal vein, hepatic artery, bile duct, and lymph nodes. MR imaging was superior to CT in showing these structures, especially bile duct and lymph nodes, which is thought to result from high contrast resolution of MR imaging.  相似文献   
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