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81.
Study of pathological morphology in chronic sinusitis]   总被引:1,自引:0,他引:1  
OBJECTIVE: To study the pathological characteristics and regularity of chronic sinusitis (CS) in different clinical types, tc estimate the reliability and feasibility of CS classification on the pathologic basis. METHODS: HE, Van Gieson's, alcian blue-periodic acid-schiff(AB-PAS) staining was used to observe the changes of epithelium, to measure the thickness of basement membrane and the area of mucous glands. The ultrastructural changes of pseudostratified ciliated columnar epithelium were observed under transmission electron microscope (TEM) and scanning electron microscope (SEM). RESULTS: The epithelial fiber tissue was increased, the basement membrane was thickened, and the mucous glands were obviously increased in CS under the light microscope. Subepithelial fibrosis and thickened basement membrane were most obviously seen in type III of CS and the hyperplasia of mucous glands was most distinct in type II. Under the TEM, abnormal structure of cilia, decrease of ciliated cells, increase of goblet cells were detected in all three CS types. Under the SEM, the cilia of every types showed the ingravescenced process of pathological changes from slight cilium disorder, disorientation, to desquamation of most cilia and replacement of microvilli. CONCLUSION: There is significant distinction of mucous membrane structure among three types. The Chinese classification of CS has pathological basis, it represents the occurrence, development and regularity of CS, and it can be used as basis in further study, communication and evaluation for surgical effect of CS.  相似文献   
82.
OBJECTIVE: To evaluate the possibility and reliability of the hyoid-sternohyoid graft transfer in the correction of server subglottic laryngotracheal stenosis, and delineate the operation skills and clinical results. METHODS: Seven patients with severe subglottic stenosis underwent laryngotracheal reconstruction using the hyoid grafts with sternohyoid muscle flaps (HG-SHMF). Five of these patients had traumatic subglottic stenosis, one with scar tissue of unknown etiology arising in the subglottic region, another with tracheal narrowing caused by inhalation of hydrochloric acid. RESULTS: All seven patients were successfully decannulated with moderate good voice. The average time from reconstruction to decannulation was 15.4 months. The stent was endoscopically removed with a range of 3 to 22 months; the mean time required for stenting was 9.6 months. Two patients who received additional salvage reconstruction procedures because of graft or stent displacement were extubated with improved voices and satisfactory airway. CONCLUSIONS: The HG-SHMF transfer was a single-stage reconstruction, relatively simple procedure that can restore an adequate airway and a good voice. Patients undergoing laryngotracheal reconstruction with HG-SHMF must have regular, long-term follow-up since graft displacement and recurrent granulation tissue or scar reformation can cause restenosis after an initially successful surgery. This procedure should be used in a large number of patients to further test its reliability.  相似文献   
83.
Progressive multifocal leukoencephalopathy (PML) is a fetal demyelinating disease in the central nervous system. PML was once a rare disease, but it is now relatively common among AIDS (acquired immunodeficiency syndrome) patients. The immunological state of patients mainly contributes to the pathogenesis of PML. Genetic changes of the etiological agent, however, may also be involved in the development and progression of the disease. The major genetic changes possibly associated with PML include the regulatory region rearrangement and the VP1 loop mutation. Both changes have been identified as genetic changes usually occurring in JCV (JCvirus) DNAs from the brain and cerebrospinal fluid of PML patients. Although it remained to be clarified how these changes are involved in the pathogenesis of PML, accumulating evidence suggests that the VP1 loop mutation is associated with the progression of PML. Here we overview studies (mainly those performed by ourselves) on these genetic changes.  相似文献   
84.
为探讨药效法估测的效应消除半衰期和效量法估测的表观半衰期对合理制订给药方案的意义和作用,以桂枝汤解热和抗炎的药物动力学实验中所得的相应参数值设计了给药方案,观察了它们在提高药效上的作用。结果表明在给药总剂量相等、首次给药同时开始的情况下,以半衰期设计的给药方案组的药效均明显高于习惯的一次给药组;而以效应消除半衰期设计给药方案组药效增强率又高于以表观半衰期设计的方案组。提示效应消除半衰期比表观半衰期似更有实践意义。  相似文献   
85.
采用辣根过氧化物酶(HRP)逆行示踪与谷氨酸免疫细胞化学结合法对大鼠额叶和枕叶皮质内胼胝体神经元的化学性质进行了研究.结果发现含谷氨酸的胼胝体神经元为大中型锥体细胞,主要分布于皮质Ⅱ/Ⅲ、Ⅴ和Ⅵ层,并有成群分布的倾向.含谷氨酸的胼胝体神经元的数目约占 HRP 标记的胼胝体神经元的17%(额叶)和29%(枕叶).这一结果从形态学上证实,大鼠大脑皮质内相当一部分胼胝体神经元使用谷氨酸作为兴奋性递质。  相似文献   
86.
北京市东城区和平里社区居民慢性病防治探讨   总被引:3,自引:0,他引:3  
为探索慢性病的防治方法,我们于1989 ̄1994年社区居民中开展了以高血压为主的循环系统慢性病防治课题,经过5年的干预,观察组与对照组居民及接受管理的高血压病人在减少吸烟,饮酒,控制食盐摄入,掌握慢性病防治知识等方面有显著性差异,取得了满意的结果,从而为今后全面开展慢性病防治积累了经验。  相似文献   
87.
以健康Wistar大白鼠为材料,对微波快速内源性过氧化物酶染色与灌注法显示微血管的方法进行了对比研究。结果,过氧化物酶组织化学法具有不用灌注,操作简单,所用时间短,对血管无扩张、破裂等人为改变的特点,保持了微血管真实的自然形态和管径大小,可以定量或半定量地判定组织器官活体时的血液循环状况。可以用于人及动物的大脑、脊髓、皮肤、耳及食管等组织内微血管形态学研究和定量分析。并对过氧化物酶显示微血管的原理和微波辐射促进染色的原理及特点进行了分析、讨论。  相似文献   
88.
在体外培养瘤细胞的实验中,胰RNA提取物对艾氏腹水瘤细胞及其他瘤细胞(S_(180),P_(88),H_(22))有杀伤作用。在胰RNA提取物中,对瘤细胞具有杀伤作用的活性物质不是性凝集素样多糖类物质或能透过半透膜的小分子化合物,而是具有二级结构的低分子RNA。  相似文献   
89.
In the present paper we report the mitogenic effect of the sheep anti-porcine lymphocyte E-receptor antiserum IgG(APERIgG) on porcine peripheral T-lymphocytes in vitro. The effect was apparently dose-dependent and not seen in the B-lymphocyte cultures. Kinetic study showed that the maximal 3H-thymidine incorporation, similar to that induced by Con A, occurred on the third day of incubation. Neither F(ab')2 nor Fab fragment of APERIgG was able to induce cell proliferation, indicating that the integrity of IgG molecule was essential for cell response. It was very interesting to note that though there is cross antigenicity between porcine and human E-receptors, no similar effect could be produced by APERIgG in human peripheral lymphocyte cultures under the same experimental conditions, suggesting the existence of minor difference in structure between the porcine and human E-receptors.  相似文献   
90.
Lung cancer and prior tuberculosis infection in Shanghai   总被引:1,自引:0,他引:1  
In a population-based case-control study of lung cancer in Shanghai involving interviews during 1984-86 with 1,405 cancer patients and 1,495 controls, a significant 50% elevation in the risk of lung cancer, adjusted for cigarette smoking, was observed among persons who had a history of tuberculosis. Among those diagnosed with tuberculosis within the past 20 years, the risk exceeded 2.5-fold. In males the lung cancers tended to occur on the same side as the previous tuberculosis infection. For both sexes, the effect of recent tuberculosis was most apparent for adenocarcinoma and peripheral tumours. No relationship was found between lung cancer risk and the type of tuberculosis therapy, including use of isoniazid. The findings suggest that tuberculosis may predispose to lung cancer, with the association most apparent among recent survivors of the infection.  相似文献   
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