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1.
目的探讨碱性成纤维细胞生长因子(basicfibroblastgrowthfactor,bFGF)对晶体上皮细胞促增殖作用的机理。方法从培养的第二代牛眼晶体上皮细胞提取RNA,经逆转录反应合成cDNA。借助从人体胎盘纤维细胞bFGF受体序列合成的寡核苷酸引物,聚合酶链反应体外扩增cDNA。扩增的cDNA片段克隆后,Sanger双脱氧链终止法测定其序列。结果探测出牛眼晶体上皮细胞bFGF受体的mRNA,测序后发现其氨基酸序列片段中仅3个氨基酸与人体不同。结论晶体上皮细胞存在bFGF受体,当bFGF与其受体结合后,对促进晶体上皮细胞的增殖以及白内障术后后囊混浊具有重要作用。  相似文献   
2.
Background Congenital pseudarthrosis of the tibia (CPT) is frequently, but not always, associated with neurofibromatosis type 1 (NF1). Double inactivation of the NF1 gene has been reported to be the pathogenesis of CPT in NF1 cases. Methods We analyzed the loss of heterozygosity (LOH) of the NF1 gene in cases of CPT with NF1 to examine whether double inactivation was seen in the case. In addition to morphological analysis, immunoexpression of differentiation markers was examined. Results and discussion The tibia tapered with the zone phenomenon from mature to immature bone with osteoblastic rimming, resembling osteofibrous dysplasia. Osteosclerotic bowed bone with a small number of osteoclasts suggested dysfunction of bone remodeling. Fibrous tissue at the site of pseudarthrosis was associated with the periosteum and demonstrated myofibroblastic differentiation accompanied by massive cartilage formation, suggesting some misdirection during the differentiation of periosteum to myofibroblasts or chondrocytes. LOH of the NF1 gene locus was not seen in fibrous tissue. This result suggests that CPT is not accompanied by double inactivation in every NF1 case.  相似文献   
3.
Primary rhabdomyosarcoma of bone is exceedingly rare. We present a case of rhabdomyosarcoma of the iliac bone in a 32-year-old male. Histologically, the tumour consisted mainly of a uniform proliferation of elongated spindle cells arranged in a herring bone pattern, simulating fibrosarcoma. Focally there was a conventional embryonal pattern with scattered rhabdomyoblasts possessing an eosinophilic cytoplasm. Immunohistochemical studies disclosed expression of muscle markers such as desmin and muscle-specific actin, in both the embryonal and spindle-cell areas and myoglobin only in the embryonal areas. Such histological features are unusual for classical embryonal rhabdomyosarcoma. The anatomical site and age of the patient are also atypical.  相似文献   
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5.
The PTEN/MMAC1 ( PTEN ) gene was identified as a tumor suppressor gene encoding a cytoplasmic protein that controls cellular processes. To investigate the potential role and the alteration of the PTEN gene in soft tissue sarcomas (STSs), we searched for homozygous deletion and promoter hypermethylation in a series of 48 STSs that was composed of malignant fibrous histiocytoma, leiomyosarcoma, malignant peripheral nerve sheath tumor, including 2 cases with a mutation that we previously reported; differential polymerase chain reaction and methylation-specific polymerase chain reaction, respectively, were used for the analyses. Furthermore, to determine whether PTEN gene alterations are involved in the down-regulation of PTEN expression, we examined the expression of PTEN protein in 38 cases in which paraffin-embedded tissues were available for immunohistochemical analysis. In addition to our previous results showing that 2 (4%) of 51 cases had a PTEN mutation, promoter methylation was recognized in 6 (13%) of 48 cases, and homozygous deletion was detected in 1 (2%) of 48 cases in the current study. Of 6 cases with promoter methylation of PTEN gene, 5 were malignant peripheral nerve sheath tumor. Decreased expression of PTEN protein was recognized in 11 (29%) of 38 STS cases. Of 9 cases with PTEN alterations (6 cases with promoter methylation, 2 with mutation, and 1 with homozygous deletion), 3 (33%) showed decreased expression of PTEN protein. Furthermore, decreased expression of the PTEN gene showed a statistically significant correlation with high MIB-1 labeling index in 38 STS cases examined ( P = .0441). In conclusion, promoter methylation and homozygous deletion of the PTEN gene were found to be relatively rare events in cases of STS, as is mutation of the gene. Of 9 cases with a PTEN alteration, 3 (33%) showed a decrease in PTEN expression, indicating that PTEN gene alterations seem to play a minor role in the inactivation of PTEN in these tumors. Furthermore, although a further detailed analysis of a larger number of cases is still necessary, the present results suggest that PTEN expression may be a useful indicator of cell proliferation in patients with STS.  相似文献   
6.
A rare case of primary pulmonary synovial sarcoma with polypoid endobronchial growth in a 42-year-old Japanese woman is described. Left upper sleeve lobectomy was performed for the polypoid tumor measuring 2.5 cm in the left major bronchus and the patient was treated with adjuvant chemotherapy. Three years later, a recurrent tumor was discovered. Microscopically, this tumor was characterized by a proliferation of oval to spindle-shaped cells arranged in sheets and fascicles and covered by the thin normal bronchial epithelium. Immunohistochemically, tumor cells were positive for vimentin, and focally positive for pancytokeratin recognized by AE1/AE3, cytokeratin 7 and epithelial membrane antigen. A chimera gene, SYT-SSX1, was detected. Recently, primary pulmonary synovial sarcoma is an increasingly recognized clinical entity; however, most of these tumors present as a parenchymal mass. The present case is a unique example of primary synovial sarcoma of endobronchial polypoid type. This case suggests that pulmonary synovial sarcoma might originate from bronchial submucosal stromal tissue.  相似文献   
7.
Immunoglobulin G4-related disease (IgG4-RD) is a fibroinflammatory condition which involves various organs. This is a very rare case of IgG4-related lung disease (IgG4-RLD) with the invasion into diaphragm. The patient was a 71-year-old man with a long-term exposure to asbestos who had a mass shadow in the left lower lung lobe, which was suspected to invade the left diaphragm on computed tomography (CT). Positron emission tomography (PET)/CT also presented an avid intake of fluorodeoxyglucose in the mass, which suspected lung cancer. Although bronchoscopic biopsy could not lead to the definite diagnosis, we performed left lower lobectomy combined with the resection of left diaphragm. The specimen showed the features of IgG4-RLD on pathology: the vein stenosis and fibrosis around the vein, the infiltration of IgG4-positive cells, and IgG cells to IgG4 cells ratio of 40%. Furthermore, there were inflammatory cells infiltrating to the diaphragm.  相似文献   
8.
Apparent diffusion coefficients of breast tumors: clinical application.   总被引:2,自引:0,他引:2  
PURPOSE: To evaluate the usefulness of apparent diffusion coefficient (ADC) for the differential diagnosis of breast tumors and to determine the relation between ADC and tumor cellularity. MATERIALS AND METHODS: One hundred and thirty-six female patients (age range, 17-83 years; average age, 51.7 years) with 140 histologically proven breast tumors underwent diffusion-weighted magnetic resonance (MR) imaging (DWI) using the spin-echo echo-planar technique, and the ADCs of the tumors were calculated using 3 different b values, 0, 500, and 1000 s/mm(2). The diagnoses consisted of fibroadenoma (FA, n=16), invasive ductal carcinoma, not otherwise specified (IDC, n=117), medullary carcinoma (ME, n=3) and mucinous carcinoma (MU, n=4). Tumor cellularity was calculated from surgical specimens. The ADCs of breast tumors and cellularity were compared between different histological types by analysis of variance and Scheffe's post hoc test. The correlation between tumor cellularity and ADC was analyzed by Pearson correlation test. RESULTS: Significant differences were observed in ADCs between FA and all types of cancers (P<0.05) and between MU and other types of cancers (P<0.01) and in cellularity between FA and cancers except MU (P<0.01) and between MU and other types of cancers (P<0.01). There was an inverse correlation between ADC and tumor cellularity (P<0.01, r(2)=0.451). CONCLUSIONS: The ADC may potentially help in differentiating benign and malignant breast tumors. Tumor ADC correlates inversely with tumor cellularity.  相似文献   
9.
Noonan syndrome (NS) is an autosomal dominant disorder characterized by facial anomalies, short stature, chest deformity, congenital heart diseases, and other comorbidities. The challenges faced during anesthetic management of patients with NS could be due to congenital heart diseases, hemostatic disorders, and airway anomalies. Here we describe dental treatment under general anesthesia performed for a 28-year-old man with NS. He had characteristic features of NS along with mild pulmonary valve stenosis. Dental treatment under general anesthesia was performed successfully on 13 occasions with nasotracheal intubation under curve-tipped suction catheter guidance or insertion of a reinforced laryngeal mask airway. This case suggests that for patients with NS, who might present several challenges, dental anesthesiologists should consider the extent of the patient''s disorders to enable them to perform dental treatment safely under general anesthesia.Key Words: Repeated general anesthesia, Noonan syndromeNoonan syndrome (NS) is an autosomal dominant disorder and was first reported by Noonan and Ehmke.1 The primary features of this multisystem disorder include hypertelorism, low-set ears, down-slanting eyes, a webbed neck, congenital heart diseases, short stature, chest deformity, and intellectual impairment.2,3 NS affects males and females equally and has an estimated incidence of 1 in 1000 to 1 in 2500 live births.2,4The challenges faced during anesthetic management of patients with NS could be due to congenital heart diseases, hemostatic disorders, and airway anomalies.58 The present report describes repeated administration of general anesthesia performed by adopting nasotracheal intubation or reinforced laryngeal mask airway insertion for a patient with NS at the time of dental treatment in our hospital.  相似文献   
10.
Background Passive smoking has been reported to induce intervertebral disc degeneration in rats, and the objective of the present study was to histologically investigate changes in smoking-induced intervertebral disc degeneration after cessation of smoking. Methods Four-week-old rats were subjected to passive smoking for 8 weeks in a smoking box [20 cigarettes a day: one cigarette an hour (inhaled over 3 minutes and followed by ventilation with room air for 5 minutes)] to induce intervertebral disc degeneration. Smoke-free periods of different lengths were then established, and intervertebral discs were histologically analyzed. Results Immediately after 8 weeks of passive smoking, intervertebral discs exhibited cracks, tears, and misalignment of the annulus fibrosus, and increased fibrous tissue was seen in the nucleus pulposus. In addition, the level of interleukin-1β in intervertebral discs was higher in the smoking group than in the non-smoking group. After cessation, progression of degeneration ceased, and the matrix of the nucleus pulposus and annulus fibrosus exhibited increased fibrous connective tissue and proteoglycan. However, there were no changes in annulus fibrosus misalignment. Interleukin-1β levels also remained significantly elevated after 8 weeks of cessation. Conclusions While the annulus fibrosus degeneration caused by smoking was partially irreversible after cessation of smoking, the amount of mucin (proteoglycan) in the nucleus pulposus and annulus fibrosus tended to increase after cessation, thus suggesting the possibility that smoking-induced intervertebral disc degeneration can be repaired to some degree by cessation of smoking.  相似文献   
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