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排序方式: 共有2147条查询结果,搜索用时 15 毫秒
1.
Akira Mogi Toshiki Yajima Kenji Tomizawa Ryoichi Onozato Shigebumi Tanaka Hiroyuki Kuwano 《Annals of thoracic and cardiovascular surgery》2015,21(5):435-439
Purpose: Small pulmonary lesions that include ground-glass attenuation have been increasingly discovered because of progressive imaging diagnostic technologies. Despite the detection of such small lesions, sometimes it is quite difficult to localize them because of their size or considerable depth from the visceral pleura. In the present study, we examined the usefulness of computed tomography-guided lipiodol marking for thoracoscopic resection of impalpable pulmonary nodules.Methods: Fifty-six patients with an undiagnosed peripheral lesion(s) of the lung who had undergone preoperative computed tomography-guided lipiodol marking followed by video-assisted thoracoscopic surgery were studied.Results: All of the nodules were successfully marked by computed tomography-guided lipiodol marking, and all except for one case were localized by means of intraoperative fluoroscopy as clear spots. With regard to complications, pneumothorax occurred in 21 patients (37.5%), and only one patient required transient drainage. Although hemorrhaging in the lung parenchyma and hemosputum occurred in nine patients (16.1%) and one patient (1.8%), respectively, no patients were in serious condition. No intra- or postoperative mortality or morbidity was observed.Conclusion: Preoperative computed tomography-guided lipiodol marking of small or impalpable pulmonary nodules is a safe and useful procedure for thoracoscopic resection of the lung. 相似文献
2.
W T Yuh E T Tali H D Nguyen T M Simonson N A Mayr D J Fisher 《AJNR. American journal of neuroradiology》1995,16(2):373
PURPOSETo evaluate the effect of MR contrast dose versus delayed imaging time on the detection of metastatic brain lesions based on lesion size.METHODSContrast MR examinations with gadoteridol were obtained in 45 patients with brain metastases. The patients were divided into two groups: 16 received cumulative standard dose (0.1 mmol/kg) and 29 received cumulative triple dose (0.3 mmol/kg). Both groups were evaluated at two dose levels (lower dose and higher dose) with two separate injections. Each patient received an initial bolus injection of either 0.05 (cumulative standard dose) or 0.1 (cumulative triple dose) mmol/kg of gadoteridol to reach the lower-dose level and underwent imaging immediately and 10 and 20 minutes later. Thirty minutes after injection, an additional bolus injection of 0.05 (cumulative standard dose) or 0.2 (cumulative triple dose) mmol/kg was administered to reach the cumulative higher-dose level (cumulative standard dose, 0.1 mmol/kg; cumulative triple dose, 0.3 mmol). Images were acquired immediately.RESULTSThere was no difference in the detection rate for lesions larger than 10 mm among T2-weighted, lower-dose immediate and delayed, or immediate higher-dose images in both study groups. Lesions smaller than 10 mm had improved detection with delayed imaging in both study groups; however, the immediate higher-dose studies still had the highest detection rate.CONCLUSIONIn the evaluation of small central nervous system metastases, either delayed imaging after the injection of standard contrast dose or higher contrast dose may improve their detection, and therefore affect clinical management. Higher contrast dose (cumulative triple dose) studies appear to be more effective than delayed imaging with standard dose. 相似文献
3.
Comparison of characteristics of esophageal squamous cell carcinoma associated with head and neck cancer and those with gastric cancer 总被引:3,自引:0,他引:3
H Kuwano M Morita S Tsutsui Y Kido M Mori K Sugimachi 《Journal of surgical oncology》1991,46(2):107-109
In ongoing reviews of 339 patients with surgically treated primary squamous cell carcinoma, there were 19 (5.6%) with concurrent gastric cancer and 11 (3.2%) with head and neck cancer. The incidences of intra-esophageal multiple occurrence of esophageal cancer are 27.3% and 26.3% in those with associated head and neck cancer and gastric cancer, respectively, and higher than 7.1% in those without such a concurrent cancer. There was no difference in the clinicopathological characteristics of those with concurrent head and neck and gastric cancers, except for the higher incidence of metachronous occurrence in the former. These findings suggest that, in cases of esophageal cancer associated with concurrent head and neck cancer and gastric cancer, intraesophageal multiplicity of the esophageal carcinoma is frequent and that preoperative serial evaluations is most important to design treatment and estimate the prognosis. 相似文献
4.
Predicting recurrence time of esophageal carcinoma through assessment of histologic factors and DNA ploidy 总被引:3,自引:0,他引:3
Cytophotometric analysis of nuclear DNA content was done in 128 patients with squamous cell carcinoma of the esophagus. The relationship among histopathologic features, DNA distribution pattern, and survival time was investigated from the standpoint of recurrence. Of 128 patients, 77 (60.1%) died of recurrence within 2 years after surgery: 16 (12.5%) from 2 to 5 years and two (1.6%) over 5 years. The rate of death of recurrence within 2 years was higher in patients with T4 or N1 than T1, T2, and T3 or N0 (P less than 0.01). Survivors over 5 years more frequently possessed type II DNA pattern than types III and IV (P less than 0.05). The rate of death of recurrence within 2 years was 34.4% in type II, which was lower than the 59.6% rate in type III (P less than 0.05) and the 76.6% rate in type IV (P less than 0.01). Survivors from 2 to 5 years were higher in type III than in type IV (P less than 0.05), and recurrence over 5 years was found only in type II. This inclination was more apparent in those with curative resection. In the patients with type II, careful follow-up may be needed over 5 years for late recurrence. However, in those with type IV, no recurrence over 2 years could be regarded as healed because most of their recurrences occur within 2 years. These findings suggest that the growth rate of esophageal carcinoma should reflect DNA aneuploidy, and the DNA analysis of esophageal carcinoma should be a valuable parameter for postoperative follow-up planning. 相似文献
5.
Lugol-combined endoscopic detection of minute malignant lesions of the thoracic esophagus. 总被引:2,自引:0,他引:2 下载免费PDF全文
Early-stage esophageal carcinomas, particularly cases of intraepithelial carcinoma and mucosal carcinoma, are extremely difficult to detect because the patients have no particular complaints, and findings on the x-rays are nil. At present, endoscopic examination is the only tool of any value for discerning such lesions. Lugol-combined endoscopy with biopsy has proven to be most effective for detecting the presence and spread of small malignant lesions of the esophagus. Studies were conducted on the diagnostic features of one intraepithelial, five mucosal and 29 submucosal carcinomas of the esophagus, detected through the use of Lugol-combined endoscopy. 相似文献
6.
The number, size, and location of cerebral infarctions, and blood flow in the middle cerebral artery as seen on proton magnetic resonance imaging were assessed in six white adults with angiographically documented moyamoya. Findings were correlated with clinical presentation, computed tomography, and angiography. Large hemispheric infarctions were found in five hemispheres, predominantly in watershed regions. Subcortical infarctions (n = 56) were found in all hemispheres. They were predominantly located in the centrum semiovale, in the distal beds of supply of the penetrating branches of the anterior and middle cerebral arteries. Infarction of the putamen was found in three hemispheres, caudate nucleus in four, globus pallidus in two, and anterior limb of the internal capsule in two. There were none in the posterior limb of the internal capsule, thalamus, brain stem, or cerebellum. Middle cerebral artery flow was visualized as a signal-void flow sign in only three hemispheres. Cerebral infarctions due to moyamoya are bilateral, multiple, often small, and asymptomatic, affecting predominantly the carotid circulation in watershed regions. Subcortical infarctions in the centrum semiovale and large hemispheric infarctions in hemodynamically compromised areas are the predominant findings. 相似文献
7.
8.
Experience with high-dose gadolinium MR imaging in the evaluation of brain metastases. 总被引:6,自引:0,他引:6
W T Yuh J D Engelken M G Muhonen N A Mayr D J Fisher J C Ehrhardt 《AJNR. American journal of neuroradiology》1992,13(1):335-345
PURPOSE: To assess the effectiveness and safety of higher doses of gadoteridol in the MR evaluation of patients with brain metastases. MATERIALS AND METHODS: Thirty-one patients with a clinical suspicion of brain metastases were studied prospectively with gadoteridol, a new, nonionic, low-osmolality contrast agent. Each patient received an initial injection of 0.1 mmol/kg and an additional dose of 0.2 mmol/kg 30 minutes later. Images were obtained before, immediately after, and 10 and 20 minutes after the initial dose. Images also were acquired immediately after the additional dose of gadoteridol. RESULTS: No adverse effects were attributed to the injection of gadoteridol. Four patients' examinations were excluded from analysis because of machine malfunction (two patients) and excessive motion artifact (two patients). Four patients had no detectable metastases. After the additional dose of gadoteridol, there was a marked qualitative improvement in lesion conspicuity and detection. The conspicuity of 80 of 81 lesions was increased in the high-dose studies, and 46 new lesions were detected in 19 of 27 patients. Quantitative image analysis demonstrated a significant increase in normalized mean lesion contrast between the initial-dose and high-dose studies (35 lesions identified in 13 patients, P less than .0001). The additional information gained by high-dose examinations contributed to a potential modification of the treatment in 10 of 27 patients. High-dose examinations increased flow-related artifact in the posterior fossa in 12 of 27 patients. CONCLUSION: Based on our preliminary results, high-dose gadolinium-enhanced MR examinations may have advantages over 0.1 mmol/kg examinations in detecting early and/or small metastases. This may be significant in the management of patients with cerebral metastases. 相似文献
9.
The major concern of the national population policy in Taiwan in recent years has been to lower the incidence of hereditary diseases and mental retardation in the general population. It has been estimated that there are around 10,000 mentally retarded school children in Taiwan. If effective chromosomal screening can be extended to these children, some of the family members who are carriers of balanced chromosomal rearrangements may benefit from follow-up studies and genetic counseling. The present report is the result of a pilot study conducted from 1988 to 1991 to explore the possibility of chromosomal screening of mentally retarded school children in Taipei. A total of 871 blood samples were collected from 1,147 children registered in 46 schools or residing in homes for the retarded. Chromosomal analysis was successfully accomplished on 674 out of 871 blood samples. The following chromosomal abnormalities were observed: 28 Down's syndrome, four Klinefelter syndrome, one XYY, one triple X, 11 translocations, seven inversions, four mosaics, three duplications, one deletion and one with an extra marker chromosome. After follow-up cytogenetic analyses of 13 families with probands with structural chromosomal anomalies, three of these families were shown to have one or two carriers of balanced translocated chromosomes. It seems that the present screening system would not be practical or cost-effective if it were applied island-wide in the future. 相似文献
10.
S Sato Y Watanabe K Okamura R Hamanaka T Mori K Kohno M Kuwano 《Anti-cancer drug design》1989,4(2):125-135
Ethyl 6-p-5-(l-imidazolyl) pentyloxyphenoxy-2, 2-dimethylhexanoate hydrochloride (YM534) is a new synthetic anti-tumor compound. Combinations of YM534 with other anti-cancer agents were examined to ascertain whether YM534 potentiated other anti-cancer agents against the KB cell line and its multidrug-resistant counterpart, VJ-300. YM534 potentiated the cytotoxic action of vincristine and actinomycin D about 2-fold against KB cells, but not those of daunomycin and adriamycin. By contrast, YM534 only slightly reversed drug-resistance to adriamycin and daunomycin in VJ-300 while it reversed 5-fold vincristine resistance and 60-fold actinomycin D resistance in VJ-300. The reversal effect of YM534 on actinomycin D and vincristine-resistance in VJ-300 cells appeared to be due to enhanced accumulation of [3H] actinomycin D and [3H] vincristine in VJ-300 cells by YM534. YM534 inhibited efflux of actinomycin D and vincristine from VJ-300 cells, and it also enhanced cellular uptake of these anti-cancer agents. YM534 enhanced cellular accumulation of both actinomycin D and vincristine in the sensitive KB cells. YM534 is thus a unique anti-cancer agent since combinations of other anti-cancer agents with YM534 are expected to augment anti-tumor activity of them. By contrast, YM212, a carboxy analog of YM534, had much less activity to potentiate vincristine and actinomycin D). YM534 at 100-1000 microM almost completely inhibited the photoaffinity labeling of [3H] azidopine to the 170-kD P-glycoprotein of VJ-300 cell membranes, but YM212 showed much less inhibitory action on the photoaffinity labeling. YM534 could also inhibit the photoaffinity labeling of deglycosylated P-glycoprotein. 相似文献