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21.
Background :
In an attempt to determine the biological significance of nuclear morphometric findings, measurements of mean nuclear volume (MNV) and nuclear roundness factor (NRF) were compared to the immunoreactivityof p53 expression and proliferating cell nuclear antigen (PCNA) in human bladder cancer.
Methods :
MNV and NRF were measured using stereological methods. Expression of p53 and PCNA were determined by immunohistochemical staining. Specimens from 111 patients with previously untreated bladder cancer were analyzed.
Results :
The mean MNV was 235.8 ± 1 33.6 μm3 for the 81 patients with p53-labeling index (LI) less than 10% and 337.2 ± 141.0 μn3 for the 30 patients with p53 LI greater than 10% (P = 0.008). There was Resign if icant correlation between NRF and expression of p53. The mean MNV was 220.1 ± 1 20.5 μm3 for the 67 patients with PCNA LI less than 28% (the mean value of PCNA LI) and 328.9 ± 149.2 μm3 in 44 patients with PCNA LI greater than 28% (P= 0.0001). The mean NRF was 80.7 ± 4.2 for the 67 patients with PCNA LI less than 28%, and 82.3 ± 3.4 for the 44 patients with PCNA LI more than 28% (P= 0.04). Conclusion: Nuclear morphometric findings may reflect the proliferative potential of cancer eel Is of the bladder, as indicated by findings of immunostaining for p53 and PCNA.  相似文献   
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Five latissimus dorsi musculocutaneous flaps (LD flap) were used for reconstruction with prostheses after resection of tumors between 1984 and 1991 in our hospital. Bony structures were reconstructed with prostheses and in three cases autoclaved autobone grafts were also needed. The prostheses and adjacent grafts were then wrapped by the LD flaps. Tumor sites included one humerus, two thighs, and two knees. All but one case healed primarily. The sole case of infection was successfully treated with debridement and irrigation. Due to the LD flaps' plentiful blood supply, we believe infection of the prosthetics can be avoided and good clinical results can be achieved using the flap with autoclaved autograft prosthetic composite reconstruction. © 1994 Wiley-Liss, Inc.  相似文献   
25.
We raised polyclonal and monoclonal antibodies against rat recombinant HPC-1/syntaxin 1A lacking a transmembrane domain. The polyclonal antibody recognized two major bands at 35 and 40 kDa from rat brain membranes. A hybridoma clone designated 14D8, however, recognized only one band at 35 kDa. A polyclonal antibody detected recombinant syntaxin 1B, as well as HPC-1/syntaxin 1A on an immunoblot, whereas 14D8 recognized recombinant HPC-1/syntaxin 1A, but not syntaxin 1B. Therefore, 14D8 is specific for HPC-1/syntaxin 1A. Using this monoclonal antibody, we investigated the expression of HPC-1/syntaxin 1A in the rat hippocampal membranes. HPC-1/syntaxin 1A was present even in the embryonic d 19 (E19) hippocampal membranes, and it increased during the next two postnatal wk. Pyramidal cell axons were intensely stained with the 14D8 monoclonal antibody, suggesting that HPC-1/syntaxin 1A was not restricted to the presynaptic terminal. Furthermore, we investigated the phosphorylation of HPC-1/syntaxin 1A in the rat brain membranes. HPC-1/syntaxin 1A affinity-purified on a 14D8 IgG-coupled column was recognized by antiphophoserine antibody, but not by antiphosphotyrosine and phosphothreonine antibodies.  相似文献   
26.
Recently, a self‐expandable metallic stent has been recognized for treatment of malignant duodenal stenosis. But the complications by stenting are important problems even now. In the present study, we report our new method of duodenal stenting by using of double‐balloon enteroscopy considered safe and effective.  相似文献   
27.
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   
28.
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   
29.
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   
30.
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   
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