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991.
992.
This report deals with the image quality of film used in mammography in terms of changing the processing time of the film and reducing the radiation dose. We initially performed phantom experiments to investigate the extended process that could provide high image quality of the film. We then measured silver grain sizes using an optical microscope to investigate processing time, so that silver grains would not be coarse during the extended process. It was found that micro-calcifications could be clearly detected by the extended process by using a lower radiation dose and that the extended process did not affect coarsening of the silver grains. 相似文献
993.
Transthoracic CT-guided biopsy with multiplanar reconstruction image improves diagnostic accuracy of solitary pulmonary nodules 总被引:3,自引:0,他引:3
Ohno Y Hatabu H Takenaka D Imai M Ohbayashi C Sugimura K 《European journal of radiology》2004,51(2):160-168
OBJECTIVE: To evaluate the utility of multiplanar reconstruction (MPR) image for CT-guided biopsy and determine factors of influencing diagnostic accuracy and the pneumothorax rate. MATERIALS AND METHODS: 390 patients with 396 pulmonary nodules underwent transthoracic CT-guided aspiration biopsy (TNAB) and transthoracic CT-guided cutting needle core biopsy (TCNB) as follows: 250 solitary pulmonary nodules (SPNs) underwent conventional CT-guided biopsy (conventional method), 81 underwent CT-fluoroscopic biopsy (CT-fluoroscopic method) and 65 underwent conventional CT-guided biopsy in combination with MPR image (MPR method). Success rate, overall diagnostic accuracy, pneumothorax rate and total procedure time were compared in each method. Factors affecting diagnostic accuracy and pneumothorax rate of CT-guided biopsy were statistically evaluated. RESULTS: Success rates (TNAB: 100.0%, TCNB: 100.0%) and overall diagnostic accuracies (TNAB: 96.9%, TCNB: 97.0%) of MPR were significantly higher than those using the conventional method (TNAB: 87.6 and 82.4%, TCNB: 86.3 and 81.3%) (P < 0.05). Diagnostic accuracy were influenced by biopsy method, lesion size, and needle path length (P < 0.05). Pneumothorax rate was influenced by pathological diagnostic method, lesion size, number of punctures and FEV1.0% (P < 0.05). CONCLUSION: The use of MPR for CT-guided lung biopsy is useful for improving diagnostic accuracy with no significant increase in pneumothorax rate or total procedure time. 相似文献
994.
We report two cases of testicular abscess. The first case is in a 53-year-old man who had been suffering from diabetes mellitus. Because of cerebral infarction, he had been bedridden and a Foley catheter had been indwelt for a long period of time. The second case is in a 78-year-old man who had suffered from acute prostatitis six months earlier. In both cases, the chief complaints were high fever and painful scrotal swelling. At initial evaluation, ultrasonography revealed that the affected testes were swollen without abscess formation and an ipsilateral epididymal swelling was demonstrated in the second case but not in the first case. The urine bacterial culture (UBC) result was positive for Escherichia coli in first case and Pseudomonas aeruginosa in the second case. In both cases, fever and scrotal pain subsided after antibiotic chemotherapy, and inflammatory reactions on routine blood studies were normalized within 2 weeks. Nevertheless, the swollen testes did not sigunificantly reduce in size, and testicular abscess was suspected by magnetic resonance imaging (MRI). Orchiectomy was performed, and intratesticular abscess formations were confirmed macroscopically and microscopically. In each case, bacterial culture from the abscess was positive for the same bacterium as detected from the UBC. It is difficult to distinguish testicular abscess from acute epididymitis at the early stage because of similarities on symptoms or signs between the two. If testicular swelling lasts after appropriate chemotherapy, we believe that attention should be directed to testicular abscess, which needs orchiectomy to obtain a complete cure and MRI is useful in its diagnosis. 相似文献
995.
Maruyama M Okamoto H Suwa J Asou T Hoka S 《Masui. The Japanese journal of anesthesiology》2004,53(6):629-633
BACKGROUND: We evaluated the changes in the bispectral index (BIS) as a potential indicator of level of consciousness in infants and children undergoing fast track cardiac surgery. METHODS: Twenty-one children undergoing fast track cardiac surgery were recruited into this study. Anesthesia was maintained with inhaled sevoflurane and intravenous fentanyl 10 microg x kg(-1). Cardiopulmonary bypass (CPB) with mild hypothermia and an immediate tracheal extubation protocol were used. BIS was recorded throughout the operation. RESULTS: In average, BIS was kept almost under 70 with 0.5-3.0% of sevoflurane. During rewarming from mild hypothermia, BIS increased temporarily over 70 in about a half of children. We, therefore, treated them by increasing sevoflurane concentration. Nineteen children were extubated in the operating room, and two patients were extubated in ICU within three hours after surgery. CONCLUSIONS: BIS was kept within the level of adequate sedation during surgery. However, since the increase in BIS during the rewarming phase could reflect light anesthesia, caution should be taken around this phase. 相似文献
996.
Endoscopic features of impacted ureteral stones 总被引:10,自引:0,他引:10
PURPOSE: We retrospectively evaluated endoscopic findings in 165 patients with impacted ureteral stones to determine the incidence of associated ureteral lesions and predisposing factors for such lesions. MATERIALS AND METHODS: From July 1993 to March 2003 we performed retrograde endoscopic treatment in 165 patients with ureteral stones that had been impacted for more than 2 months. Average maximum stone diameter was 15.0 mm and the mean duration of impaction was 17.6 months. Treatment was done with small caliber ureteroscopes and a laser lithotriptor. We analyzed the endoscopic findings and determined the outcome by reviewing the clinical records and radiographic studies. RESULTS: Endoscopic observation revealed inflammatory ureteral polyps associated with calculi in 51 patients (30.9%). Endoscopic biopsy of 5 polyps was performed. Histological examination showed no malignancy and only chronic granulomatous inflammation of the ureter. Endoscopic observation also detected ureteral stricture in 28 patients (17.0%). Patients with polyps and strictures had long-term impaction (median 12 and 24 months, respectively), which was significantly longer than in patients without ureteral lesions (4 months). CONCLUSIONS: Endoscopic observation revealed that long-term impacted stones were frequently associated with ureteral polyps and strictures. Although concurrent ureteral lesions can make it more difficult to approach the calculus in patients with impacted stones, we found that a small caliber flexible endoscope was effective and laser fragmentation could be achieved easily. 相似文献
997.
Maruyama K Sakai H Miyazawa H Iijima K Toda N Kawahara S Hara K 《Journal of anesthesia》2004,18(4):237-240
Purpose To determine the effect of laryngotracheal application of different doses of lidocaine spray on postoperative sore throat and hoarseness, we evaluated the incidence and severity of these complications in 168 ASA I–III patients aged 15–92 years in a placebo-controlled study.Methods After induction of anesthesia with propofol, ketamine, fentanyl, and vecuronium, the laryngotracheal area was sprayed immediately before intubation with lidocaine spray either 5 times (L5 group, n = 47) or 10 times (L10 group, n = 48) or with normal saline 1ml (placebo group, n = 51). Postoperative sore throat and hoarseness were evaluated immediately after surgery and on the day after surgery.Results The incidence of sore throat was significantly higher in the L10 group than in the placebo group on both the day of and the day after surgery. The severity of sore throat was significantly higher in the L5 and L10 groups than in the placebo group on the day of surgery. On the day after surgery, the severity of sore throat remained significantly higher in the L10 group than in the placebo group. Although the incidence and severity of sore throat increased in a dose-dependent manner, these were not significantly different between the L5 and L10 groups. In addition, the incidence and severity of hoarseness did not differ at all among the three groups.Conclusion We recommend that applications of lidocaine spray to the laryngotracheal area should be avoided to help eliminate unnecessary postoperative sore throat, thereby leading to improvement in patient satisfaction. 相似文献
998.
Maruyama M Kenmochi T Asano T Saigo K Miyauchi H Miura F Ochiai T 《Journal of Hepato-Biliary-Pancreatic Surgery》2004,11(4):290-292
Because of recent progress in imaging modalities, the opportunities to detect pancreatic cystic neoplasms are increasing. However, serous cystadenoma is still uncommon. We report a case of serous cystadenoma treated by laparoscopic distal pancreatectomy. A 52-year-old woman presented with mild upper abdominal pain. Dynamic computed tomography (CT) revealed a solitary cystic lesion 3cm in diameter in the pancreatic tail. Endoscopic ultrasound showed a honeycomb pattern, indicative of serous cystadenoma. To obtain the final diagnosis of the tumor, we performed laparoscopic distal pancreatectomy. A histopathological study showed microcystadenoma with no evidence of malignancy. 相似文献
999.
Fukuta D Miyagawa S Kubo T Kusama T Shirasu A Hattori H Shirakura R 《Transplant immunology》2004,12(2):109-114
The cell membrane-bound forms of whole factor I (fI-PI), the light chain of the serine protease (SP) domain (SP-PI), and the light chain plus the COOH-terminal 45 amino acid (AA) of the heavy chain (SP+45-PI) were constructed. Chinese hamster ovary (CHO) cells, expressing these molecules were established by transfection of cDNA and confirmed by flow cytometry. Amelioration of complement-mediated cell lysis and complement fragment deposition on the cell surface by the transfectant molecules was tested in each CHO cell by means of a lactate dehydrogenase (LDH) assay and flow cytometry, respectively. A highly expressed fI-PI blocked human complement-mediated cell lysis by approximately 84% of the cells. CHO cell transfectants with SP-PI also showed a clear inhibition in cell lysis by human serum, whereas CHO cell transfectants with SP+45-PI showed no inhibition. In addition, fI-PI and SP-PI, but not SP+45-PI, suppressed C5b-9 deposition on CHO cell surface. These data indicate that the last 45 amino acid of the heavy chain, including a disulfide bridge area, did not participate in the serin protease function of factor I. The results suggest that SP-PI has potential for use in clinical xenotransplantation. 相似文献
1000.
Osawa Y Kawamura K Kondo D Imai N Ueno M Nishi S Iino N Okada M Suzuki Y Hoshino S Yamazaki H Kishimoto H Shimada H Yamagishi T Ishiyama T Narita I Gejyo F 《Clinical and experimental nephrology》2004,8(2):127-133
Background Amyloid light-chain (AL)-type amyloidosis is a plasma cell disorder with a poor prognosis for survival. Although prognostic factors, such as the number of organs involved and heart function or failure in respond to therapy have been clarified based on studies including a large series of patients, there are large interindividual differences in the prognosis of patients with primary AL-type renal amyloidosis.Methods To clarify the prognostic factors of AL-type renal amyloidosis, we retrospectively investigated the clinical manifestations, histopathological data, and prognosis of 21 patients with amyloidosis, who had been diagnosed by renal biopsy.Results Eleven patients died, at a mean observational time of 21.7 months after renal biopsy, whereas the mean observational time was 51.0 months for the 10 patients who survived. The creatinine clearance rate was significantly higher, and the serum creatinine concentration and the grade of interstitial damage were significantly lower in surviving patients (P < 0.05). The presence of amyloid fibrils in organs other than the kidney did not influence prognosis for survival. However, the intraventricular septum was thinner in surviving patients (P < 0.1). Thirteen patients had undergone melphalan-prednisolone therapy, but it did not affect prognosis for survival. Cox proportional hazard regression analysis revealed that the renal function at the time of diagnosis was a significant and independent prognostic factor for survival.Conclusions Our study demonstrated that renal function at the time of biopsy and renal interstitial damage are the best predictors of survival in AL-type renal amyloidosis. 相似文献