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51.
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   
52.
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   
53.
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   
54.
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   
55.
56.
BACKGROUND AND PURPOSE: The potential risk of prolongation of treatment time in cervical cancer has been reported for many low-dose rate (LDR) studies, with an estimated loss of local control ranging from 0.3 to 1.6% per day of treatment prolongation. Since the treatment schedule for fractionated high-dose rate intracavitary brachytherapy (HDRICB) is not directly comparable with that for low-dose rate studies, this report aims to evaluate the adverse effect of treatment prolongation specifically for cervical cancer treated with HDRICB. MATERIAL AND METHODS: From September 1992 to December 1997, 257 patients diagnosed with uterine cervical cancer (35 Ib, 26 IIa, 122 IIb, 10 IIIa, 57 IIIb, 7 IVa), who underwent external radiotherapy combined with between two and four courses of HDRICB and a minimum of 3 years of follow-up (median 57 months), were analyzed. Treatment consisted of irradiation of the whole pelvis with 44-45 Gy consisting of 22-25 fractions by 5 weeks, with the dose boosted to 54-58 Gy (with central shielding) for patients diagnosed as FIGO stage IIb-IVa bilateral parametrial disease. HDRICB was performed using an Ir-192 remote afterloading technique at 1-week intervals. The standard prescribed dose for each course of HDRICB was 7.2 Gy to point A for three insertions (before July 1995), or 6.0 Gy to point A for four insertions (after July 1995). Total prescribed point A doses (external beam radiotherapy+HDRICB) ranged from 58 to 71.6 Gy (median, 65.6 Gy) for stage IB-IIA, while analogous dosage for larger lesions (stage IIb-IVa) ranged from 59 to 75.6 Gy (median, 65.6 Gy). Kaplan-Meier and multivariate analyses were used to test the effect of treatment time on pelvic control rate (PCR) and cause-specific survival (CSS) at 5 years. RESULTS: Median treatment time was 63 days. For all stages of disease, the 5-year CSS and PCR were significantly different comparing treatment times of less than and greater than or equal to 63 days [83% and 65% (P=0.004], 93% and 83% (P=0.02), respectively]. These associations were also significant for stage Ib/IIa [97% and 79% (P=0.01), and 100% and 87% (P=0.02), respectively), but not for stage IIb [75% and 72% (P=0.79), and 93% and 87% (P=0.83), respectively] or stage III [66% and 49% (P=0.2), and 83% and 72% (P=0.21), respectively]. Multivariate analysis identified three prognostic factors for CSS, stage (P<0.001), tumor response to external RT (P=0.001), and overall treatment time (OTT; P=0.006). Prognostic factors for pelvic failure were stage (P<0.001), tumor response to external RT (P=0.001), and OTT (P=0.03). Prolongation of treatment time resulted in a daily decrease in pelvic control rate of 0.67% overall, and 0.43% for stage Ib-IIa, 0.57% for stage IIb, and 0.73% for stage III patients. CONCLUSION: Analysis of the data from the current study demonstrates that the adverse effect of treatment prolongation was observed later in the treatment course for the high-dose rate (HDR) series compared to the LDR analog, however, treatment-time prolongation still negatively influenced the cause-specific survival and pelvic control rate for both dosage groups.  相似文献   
57.
Background  High-quality attenuation maps are critical for attenuation correction of myocardial perfusion single photon emission computed tomography studies. The filtered backprojection (FBP) approach can introduce errors, especially with low-count transmission data. We present a new method for attenuation map reconstruction and examine its performance in phantom and patient data. Methods and Results  The Bayesian iterative transmission gradient algorithm incorporates a spatially varying gamma prior function that preferentially weights estimated attenuation coefficients toward the soft-tissue value while allowing data-driven solutions for lung and bone regions. The performance with attenuation-corrected technetium 99m sestamibi clinical images was evaluated in phantom studies and in 50 low-likelihood patients grouped by body mass index (BMI). The algorithm converged in 15 iterations in the phantom studies. For the clinical studies, soft-tissue estimates had significantly greater uniformity of mediastinal coefficients (mean SD, 0.005 cm−1 vs 0.011 cm−1; P<.0001). The accuracy and uniformity of the Bayesian iterative transmission gradient algorithm were independent of BMI, whereas both declined at higher BMI values with FBP. Attenuation-corrected perfusion images showed improvement in myocardial wall variability (4.8% to 4.1%, P=.02) for all BMI groups with the new method compared with FBP. Conclusion  This new method for attenuation map reconstruction provides rapidly converging and accurate attenuation maps over a wide spectrum of patient BMI values and significantly improves attenuation-corrected perfusion images.  相似文献   
58.
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   
59.
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   
60.
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   
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