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31.
Clinical, experimental and electronmicroscopic observations, and computer-enhanced images were made on 5 patients with tinea favosa resistant to griseofulvin. The pathologic fungus was identified as the Mongolian variant of Trichophyton schoenleini. The results of physical examinations, routine tests of blood, urine and stool, liver and immunologic function examinations were normal in all of the 5 patients. Under scanning electron microscopy, the surface of the spore showed pineapple-like form, the cluster of the acrogenous spores presented flower shape, and the antler-like hyphae appeared twisted in the culture. They were observed by transmission electron microscope and the images were processed by microcomputer. It was found that the cell walls of the fungi consisted of 8 layers, among which the inner layer was loose and contained cytoplasm. It was also found that all structures within the cytoplasm possessed a 1-3 layer intact envelope and there was chromatin in the nucleus. These may be contributing factors in the development of resistance to griseofulvin. This multiple-layered thick cell wall may act as a barrier responsible for the impermeability of the cell of fungi to griseofulvin.
  相似文献   
32.
Whole pancreas isografts or allografts (ACI donors, RT1a) with bladder drainage of exocrine secretions were performed in Lewis rats (RR1(1] with streptozotocin-induced diabetes. Urinary amylase, pH, and volume and serum glucose were measured daily. They were analyzed alone, or in combination, to determine patterns in deviations from normal values, from isograft control values, or from a posttransplant baseline in relation to rejection (defined as reversion of plasma glucose of greater than 200 mg/dl) in nonimmunosuppressed recipients. Also studied were the sensitivity and specificity by which such deviations predicted rejection. Functioning grafts were associated with increased urinary amylase and pH compared with normal or diabetic controls; urinary volume was less than that of diabetic rats, but greater than that of normal rats. In nonimmunosuppressed allograft recipients (n = 9), rejection occurred at a mean (+/- SD) of 7.78 +/- 0.44 days. Serum glucose rose to above normal (greater than 134 mg/dl) 1 day before rejection in 3 animals (sensitivity 33%, false negative rate 66%; false positive rate in 9 isograft recipients, 44%). Urinary volume dropped below 3 ml at a mean of 3.17 +/- 0.98 days (range 2-5 days) before rejection in 6 animals (sensitivity 66%, false negative rate 33%; false positive rate 0%). Urinary pH fell below 7.25 at a mean of 3.13 +/- 1.81 days (range 1-5 days) before rejection in 8 rats (sensitivity of 89%, false negative rate 11%; false positive rate 29%). Urinary amylase dropped from a posttransplant peak at a mean of 3.56 +/- 1.42 days (range 1-6 days) before rejection in 9 animals (sensitivity 100%, false negative rate 0%; false positive rate 43%), and dropped below 1500 units per 24 hr at a mean of 2.00 +/- 1.32 days (range 1-5 days) before rejection in 8 animals (sensitivity 89%, false negative rate 11%; false positive rate 0%). A drop in urinary amylase combined with a drop in urinary volume or pH occurred at a mean of 3.22 +/- 1.48 days (range 1-5 days) before rejection in 9 rats (sensitivity 100%, false negative rate 0%; false positive rate 0%). In a separate group of 10 allograft recipients, immunosuppression with prednisone and cyclosporine was begun concomitant with, or within 2 days of, the drop in urinary amylase from the peak value; rejection did not occur in 3 animals and was delayed to a mean of 12.0 +/- 5.0 days posttransplant in 7 animals (P less than .05 compared with the nonimmunosuppressed group).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
33.
刘红刚  郑麟蕃 《中华医学杂志》1994,74(2):92-93,T011
用Warthin-Starry螺旋体特殊染色法及透射电镜观察,分别在19例肉芽肿性唇炎和5例梅罗综合征(MRS)病人的病变组织内发现有螺旋体存在,并对其在光,电镜下的形态和在病变组织内的分布部位进行了描述。经用大刘量青霉素治疗11例病人,10例有效。本结果为MRS的发可能和螺旋体感染有关的推测提供了依据。  相似文献   
34.
应用电子自旋共振波谱仪(ESR)直接检测了缺血-再灌注兔心肌肌浆网自由基的变化,以探讨肌质网系统与氧自由基的关系。实验中将20只兔随机分为再灌注对照组、超氧化物歧化酶(SOD)组、ATP-氯化镁组和人参皂甙Re组。实验结果,g值2.0046处为半醌自由基波谱,其相对浓度各组依次为78.94±2.126,14.46±2.86,20.65±7.65,14.66±3.67(x±SD),对照组与用药组均有显著性差异(P<0.05),表明缺血-再灌注兔心肌肌浆网产生大量的自由基,用ESR可以直接检测到半醌自由基,外源性高能磷酸盐制剂ATP-氯化镁及人参皂甙Re与超氧化物歧化酶一样,发挥清除兔心肌肌浆网自由基的作用。  相似文献   
35.
36.
术中使用缓释型5-FU对于进展期结肠癌的疗效研究   总被引:3,自引:0,他引:3  
随着生活水平的提高,恶性肿瘤的发病率也逐年增高,最新资料统计表明,目前全球结肠直肠癌病人每年有100万之多[1]。在我国其发病率近年来也呈明显上升趋势,到目前为止,结肠直肠癌病人的术后5年生存率也一直徘徊在50%左右[2]。因而如何有效地进行结肠肿瘤治疗,无论是在手术还是在其他辅助治疗方面都值得我们深入地探讨和研究。  相似文献   
37.
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   
38.
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   
39.
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   
40.
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   
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