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991.
本文应用透射电镜观察了在较低剂量131I作用大鼠甲状腺滤泡上皮细胞超微结构的变化特点,分析了线粒体的变异发生率,并应四川大学研制的MIAS-300图像分析系统和用形态计量学方法,测定了胞质内粗面内质网的二维和三维形态计量学参数。结果表明:所测的各项参数都有随剂量增高而增大的趋势,并呈现较好的效应剂量依赖关系。由此计算的D25值和D50值,以粗面内质网体积密度的变化最为明显。提示,低剂量131I作用于滤泡上皮细胞,其早期应重视内质网的损伤效应,以及由此导致合成类固醇激素和外源性蛋白质的障碍 相似文献
992.
993.
Otolaryngological findings in congenital nasolacrimal duct obstruction and implications for prognosis
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AIM: To investigate otolaryngological abnormalities associated with congenital nasolacrimal duct obstruction (CNLDO) and their effect on the prognosis. METHODS: 65 consecutive cases of CNLDO were followed up with routine otorhinolaryngological examination with tympanometry. RESULTS: Otitis media with effusion (OME) and uvula bifida were detected in 44.6% and 9.2% of the children, respectively. Medical treatment and probing were less effective in patients with OME (p<0. 05). CONCLUSIONS: OME and uvula bifida are significant anomalies associated with CNLDO and the former has a marked effect on the prognosis. This finding may help to determine the patients who will need further treatment after massage and probing. 相似文献
994.
Subretinal fluid levels of topical, oral, and combined administered ciprofloxacin in humans
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Cekiç O Batman C Yaşar U Başci NE Zilelioğlu O Bozkurt A 《The British journal of ophthalmology》2000,84(9):1061-1063
AIMS: To investigate the subretinal fluid (SRF) penetration of ciprofloxacin following topical, oral, and combined administration. METHODS: 34 patients undergoing conventional retinal reattachment surgery were randomly assigned to three groups. Twelve patients received topical ciprofloxacin, 11 patients received oral ciprofloxacin, and the other 11 patients received combined drug administration. SRF drug level was measured by using high performance liquid chromatography method. RESULTS: The highest drug concentrations of all tested modes were attained following combined administration and lowest following topical administration (p<0.001). The SRF drug concentration following oral administration was also significantly higher than that of topical administration (p<0.001). Concentrations after oral and combined administration did not differ significantly (p = 0.217). CONCLUSIONS: Topical ciprofloxacin can penetrate SRF. Ocular bioavailability of ciprofloxacin in SRF after oral and combined administration is equivalent. 相似文献
995.
A new series of 3'-flavonyl-2,4-thiazolidinedione, 2,4-imidazolidinedione and 2-thiohydantoin derivatives (1-10) were synthesized and their chemical structures have been elucidated by various spectral data. The prepared compounds were tested for their insulinotropic effects in INS-1 cells. Inhibitory effects were observed for compounds 1 and 2. In contrast compounds 4, 7 and 8 were able to increase insulin release compared with glibenclamide. 相似文献
996.
997.
The epineural repair technique, which is the gold standard of peripheral nerve injuries, is still far from being ideal. The purpose of this study was to investigate the effects of the turnover epineural sheath tube (TEST) when used over the primary nerve repair site to improve nerve regeneration. Twenty-five Wistar rats were divided into three groups and were operated. In the sham control group, the sciatic nerve was dissected from the sciatic notch to its bifurcation and was left intact. In the primary epineural repair group an incision was made on the nerve and it was repaired using six epineural sutures. In the TEST group, after the incision was made the nerve ends were approximated with two epineural sutures. A proximal circular epineural incision was then made to enable the epineurium to be turned and slid over the repair site. Functional recovery was evaluated by walking tract analysis, and the sciatic functional index was calculated. Histomorphometric studies of the sciatic nerves and gastrocnemius muscles were also performed 3 months postoperatively. Three months postoperatively, functional analysis and nerve and muscle histomorphometric studies revealed similar results in the primary repair and TEST groups. There was no significant difference (p > 0.05) between the results of the TEST and the primary nerve repair groups. However, during the microscopic examination, a decrease in both foreign material reaction and an inflammatory response with less fibrosis were observed in the TEST group. The TEST has a nerve-healing property similar to primary epineural repair, with the advantage of a reduced number of sutures, which decreases the fibrosis around the repair site. The TEST is an alternative treatment modality among other techniques, especially for polyfascicular peripheral nerves. 相似文献
998.
Resurfacing of the medial canthal region and bony nasal dorsum is a problem frequently encountered after tumor excisions. Traditional flaps used in this region from the glabellar and frontal areas are bulky, and donor site scar may be unsightly. A medial pedicled orbicularis oculi myocutaneous flap is an alternative. A total of 12 flaps have been used to resurface the defects secondary to basal cell carcinoma excisions, with a mean follow-up of 10 months. All flaps survived. The flap elevation is easy and fast, and the flap can be extended to the contralateral site when needed. The skin match is good and donor morbidity is minimal. 相似文献
999.
Efficacy of immunosuppressive therapy in IgA nephropathy presenting with isolated hematuria 总被引:7,自引:0,他引:7
Harmankaya O Oztürk Y Baştürk T Obek A Kiliçarslan I 《International urology and nephrology》2002,33(1):167-171
The role of immunosuppressive therapy in the management of IgA nephropathy (IgAN) remains controversial. No consensushas yet emerged on the specific treatment of IgAN and this ismostly related to the lack of complete understanding of themultifactorial pathogenesis of the disease. Choice of appropriatetherapeutic agents is further limited by the difficulty inidentifying patients who would most likely benefit from therapy.Immunosuppressive therapy has not been recommended in patientswith isolated hematuria and well preserved renal function becauseof their generally favourable prognosis and there are no clinicaltrials in this area. Considering that mild IgAN may be an earlystage of the disease and can be reversed by immunosuppressiveagents we have used prednisolone and azathioprine in patientswith isolated hematuria in a prospective, randomized, controlledstudy since 1988. In this prospective study we have evaluated theeffect of prednisolone with azathioprine on the clinical courseof IgAN and its impact on histologic parameters and preventionof progression in patients with isolated hematuria. We studied 43biopsy-proven IgAN patients (29 males and 14 females, agedbetween 13–63 years, mean age 28 ± 6) with isolated hematuria andwell-preserved renal function (Ccr 89.2 ± 10.2 ml/min). Thepatients were assigned to two groups: 21 patients receivedprednisolone (40 mg/day) and azathioprine (100 mg/day) orally forfour months (group A) and 22 patients received no specifictreatment for IgAN and served as a control group (group B). InGroup A prednisolone was reduced to 20 mg/day at the end of thesecond month, then slowly tapered over a two-month period andstopped. The median duration of follow-up was 60 months (range12–120 months). At the end of the therapy hematuria disappearedin 17 patients. In three patients who did not respond to therapy,microscopic hematuria persisted. Of the 22 patients of group B,three had episodes of gross hematuria and proteinuria >500mg/day. No significant changes in biochemical profile wereobserved in either group. Thirteen patients (eight from thetreated, five from the untreated group) underwent a repeat biopsyafter 12 ± 6 months (range 10–25). An improvement ofhistopathological features was noted in Group A, whiledeterioration was noted in Group B. We conclude that earlytreatment with prednisolone and azathioprine appears to bebeneficial in preventing the progression of immunologic renalinjury and in improving histopathological features in IgANpatients with isolated hematuria. 相似文献
1000.
We report a rare benign renal tumor, the cystic nephroma (CN) in a 35-year old man. CN should be considered in the differential diagnosis when clinical and radiological examinations reveals a multilocular cystic renal mass, but histopathological examination is the unique diagnostic mean. 相似文献