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31.
Release fluoroimmunoassay (RFIA), a new method of enzyme immunoassay (ELISA), was employed for the detection of specific IgE antibody in patients allergic to Japanese cedar pollen. RFIA clearly discriminated between allergic patients and healthy subjects. Further, RFIA was able to detect the minute IgE antibody at the dilution range of 1/32 of patient's serum. Correlation between the relative fluorescent unit values and the RAST values of sera from 17 patients and seven healthy subjects was very high. The correlation coefficient was 0.87. These findings show that the RFIA has an advantage over the other procedures for the diagnosis of immediate-type hypersensitivity as well as the diagnosis of Japanese cedar pollen.  相似文献   
32.
A case of traumatic spinal subarachnoid hematoma causing compression of the cauda equina is reported here. The patient, a 76 year-old woman, who had fallen down by accident 1 month before, was admitted to our hospital presenting lumbar pain radiating into her right thigh, monoplegia of the right leg and urinary incontinence. Myelography and metrizamide CT demonstrated a filling defect mimicking intradural extramedullary tumor at the level of L1 and L2. Magnetic resonance imagings (MRI) revealed a subacute or chronic hematoma compressing the conus medullaris and the cauda equina. Operation was performed and an old hematoma, which occupied most of the spinal subarachnoid space and compressed the conus and cauda equina from right to left, was removed. No definite bleeding point was detected and no traumatic change was seen on the cord. Neither tumor nor abnormal vessel was detected. After surgery, the symptoms improved partially. On a review of the literature, we found only 4 cases of traumatic spinal subarachnoid hematoma, all of which occupied the cervical or thoracic portion of the spine. Our case is the first report, except for the cases following lumbar spinal tap, of traumatic spinal subarachnoid hematoma causing compression of the cauda equina. Though usually blood in CSF diffuses immediately, a clot may be formed when a large amount of bleeding obstructs the spinal canal. In our case, furthermore, deformity and narrowing of the spinal canal had preceded for many years, following lumbar vertebral compressed fracture related with osteoporosis. This might have promoted the process of canal obstruction and clot formation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
33.
Safety evaluation of surgical materials by cytotoxicity testing   总被引:2,自引:1,他引:1  
The cytotoxicity of three kinds of commercially available absorbable hemostats [oxidized cellulose (Surgicel, gauze and cotton types), microfibrillar collagen (Avitene), and cotton-type collagen (Integran)] and one adhesion barrier [sodium hyaluronate and carboxymethyl-cellulose membrane (Seprafilm)] were comparatively assessed by a colony assay using V79 cells and a minimum essential medium (MEM) elution assay in combination with a neutral red assay using L929 cells. Strong cytotoxicity was detected for Surgicel by both the MEM elution assay and the colony assay. For Avitene, both methods revealed weak cytotoxicity. For Seprafilm, no cytotoxicity was detected by the MEM elution assay, while a moderate degree of cytotoxicity was observed in the colony assay. For Integran cytotoxicity was not detected by either the MEM elution or the colony assay. The results of the different methods showed some inconsistency in terms of the degree of cytotoxicity of the materials. It is proposed that the combination of two or more sensitive cytotoxicity testing methods for the evaluation of biomaterials is necessary to avoid false-negative results for biomaterials at the preclinical stage. Furthermore, investigation of the correlation between the cytotoxicity and the extraction period of the surgical materials is helpful for predicting the effect of prolonged in vivo use of biomaterials on surrounding cells, tissues, and organs.  相似文献   
34.
35.
OBJECTIVE: It is controversial whether a systematic mediastinal lymph node dissection (MLND) needs to be performed in all patients with stage I lung cancer. The present study was done to examine the new sentinel lymph nodes hypothesis based on the lobe of the primary tumor. METHODS: In our first study, the lymph node (LN) metastases were assessed in 291 stage I non-small cell lung cancer (NSCLC) patients who had a major lung resection with a systematic mediastinal lymph node dissection. We evaluated the validity of using our new sentinel lymph nodes method based on the lobe of the primary tumor as follows: the pretracheal (#3), tracheobronchial (#4), and hilar nodes (#10) for right upper lobe tumors; #4, subcarinal (#7), and #10 for middle lobe tumors; the subaortic (#5), paraaortic (#6), and #10 for left upper lobe tumors; and the #7, #10, and interlobar nodes (#11) for tumors in either lower lobes. In the second study, we performed a lobectomy with new sentinel node sampling in 64 patients with preoperative complications. If all of the sampling nodes showed no metastases on frozen section diagnosis, systematic node dissections were not performed. RESULTS: Six of 291 patients in the first study had skip metastases that did not involve the new sentinel nodes; 5 of the 6 patients had macroscopic pleural invasion. Thus, we defined pleural invasion as an exclusion criterion for the second study. In the second study, the median follow-up time was 39 months. Metastatic lymph nodes were detected in 11 of 64 patients. Fifty-three patients (83%) had no metastasis in the sampled nodes, and, therefore, a mediastinal lymph node dissection was not done. The morbidity rate in the sampling group was 36%, and there was no mortality. In the sampling group, local recurrences were observed in two patients, distant metastases in eight, and carcinomatous pleuritis in one; the overall 5-year survival rate was 82%. CONCLUSIONS: We found that it is possible to perform a less invasive lymphadenectomy for patients with stage I lung cancer using intra-operative sampling of new sentinel lymph nodes.  相似文献   
36.
Although the causes of stroke are diverse, thromboembolism due to a mobile aortic thrombus is rare. We describe a surgical case of acute massive pulmonary embolism after critical cerebral infarction associated with a mobile ascending aortic thrombus in a 52-year-old woman. Concomitant surgical removal of the aortic thrombus and pulmonary embolectomy was performed successfully, and the patient has been stable without recurrent thromboembolic complications after 18 months of follow-up.  相似文献   
37.
Abnormal DNA content has been considered as an additional criterion for determining the biological behavior of a tumor. Flowcytometric DNA analysis was done on 121 patients with thyroid carcinoma encountered during the period between 1975 and 1987. Tumor tissues were sampled from paraffin-embedded blocks and the histology of thyroid carcinoma found to consist of 91 papillary, 23 follicular, 2 medullary, 1 squamous cell and 4 anaplastic carcinomas. The incidence of aneuploidy in thyroid carcinoma was 7.4 per cent (9 patients) while that of diploidy was 92.6 per cent (112 patients). The aneuploid specimens consisted of 6 papillary, 1 follicular, 1 medullary and 1 anaplastic carcinomas and, of 4 anaplastic carcinoma patients with subsequent death within 6 months, only 1 was aneuploid. As an indicator of proliferative potential, S-phase fraction (SPF) was also determined by flow cytometry, but this could not be used as an independent prognostic factor. The aneuploid patients showed a significantly decreased survival rate (p less than 0.01). Thus, although DNA measurement proved useful for predicting the survival of aneuploid patients, there is some discrepancy between DNA content and the biological behavior of the tumor.  相似文献   
38.
A 39 year-old Japanese female patient with a duplication of the distal portion of the common bile duct is presented herein. Moreover, an abnormal arrangement of the pancreaticobiliary ductal union, congenital biliary dilatation and carcinoma of the gallbladder were all demonstrated by cholangiographic and endoscopical studies. The patient underwent radical surgery for advanced adenosquamous carcinoma of the gallbladder, and her postoperative course was satisfactory. A reflux of pancreatic juice into the bile duct was demonstrated, but it was eliminated and considered to be a contributory etiologic factor of the gallbladder carcinoma.  相似文献   
39.
A video-assisted right upper lobectomy was successfully performed on a 58-year-old man with an anomalnous segmental pulmonary vein. The tumor was a peripherally located adenocarcinoma. The anomalous vein behind the right main bronchus was identified and safely divided. This case emphasized that to perform this procedure successfully, (1) a careful preoperative evaluation of the anatomy, including the presence of any possible vascular and/or bronchial anomalies, is necessary, and (2) if any anatomical structures cannot be determined intraoperatively, a conversion into an open procedure must immediately be undertaken.  相似文献   
40.
Frequent loss of heterozygosity at chromosomal loci in a specific tumor type may indicate the presence of a tumor suppressor gene. We have examined loss of heterozygosity on chromosome 8p in paired tumor and constitutional DNA from 346 patients representing seven different types of human cancer. Frequent allelic losses were observed in hepatocellular carcinoma (22 of 46 cases, 47.8%), in colorectal cancer (12 of 26, 46.2%), and in non-small cell lung cancer (14 of 35, 40.0%), in contrast to low frequencies detected in breast cancer (5 of 56, 8.9%) and renal cell carcinoma (2 of 27, 7.4%). Ovarian cancer and gastric cancer showed intermediate frequencies of 33.3% and 22.2%. Subsequent analysis of 120 hepatocellular carcinomas and 94 colorectal cancers with five polymorphic markers along the short arm of chromosome 8 defined commonly deleted regions within the same chromosomal interval, 8p23. 1-8p21.3, suggesting that one or more tumor suppressor genes for both cancers may be present in that region.  相似文献   
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