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31.
目的 研究异型增生程度不同的口腔白斑和不同分级的鳞癌中谷胱苷肽S转移酶π(GST π)的表达 ,探讨GST π在口腔鳞癌发生发展中的作用。 方法 采用免疫S -P法 ,对 5 4例轻、中、重度异型增生 ,4 7例高、中、低分化的口腔鳞癌 ,7例口腔粘膜上皮单纯增生患者组织进行GST π检测。 结果 口腔粘膜上皮单纯增生组织中未见GST π的表达 ,轻、中、重度异型增生病例中的GST π阳性率分别为4 7.8%、5 2 .9%和 6 4 .2 % ,高于单纯增生组 (P <0 .0 1) ;高分化鳞癌GST π阳性率为 6 4 .7% ,中、低分化鳞癌组分别为 2 8.5 %及 2 2 .2 % ,中、低分化鳞癌组表达均低于高分化鳞癌组及异型增生组 (P <0 .0 5 )。 结论 GST π表达的变化与口腔鳞癌早期的发生发展密切相关  相似文献   
32.
This study was conducted to investigate the hypocholesterolemic effect of simvastatin (30 mg/kg BW) and antioxidant effect of coenzyme Q10 (CoQ10, 15 mg/kg BW) or green tea (5%) on erythrocyte Na leak, platelet aggregation and TBARS production in hypercholesterolemic rats treated with statin. Food efficiency ratio (FER, ADG/ADFI) was decreased in statin group and increased in green tea group, and the difference between these two groups was significant (p<0.05). Plasma total cholesterol was somewhat increased in all groups with statin compared with control. Plasma triglyceride was decreased in statin group and increased in groups of CoQ10 and green tea, and the difference between groups of statin and green tea was significant (p<0.05). Liver total cholesterol was not different between the control and statin group, but was significantly decreased in the group with green tea compared with other groups (p<0.05). Liver triglyceride was decreased in groups of statin and green tea compared with the control, and the difference between groups of the control and green tea was significant (p<0.05). Platelet aggregation of both the initial slope and the maximum was not significantly different, but the group with green tea tended to be higher in initial slope and lower in the maximum. Intracellular Na of group with green tea was significantly higher than the control or statin group (p<0.05). Na leak in intact cells was significantly decreased in the statin group compared with the control (p<0.05). Na leak in AAPH treated cells was also significantly reduced in the statin group compared with groups of the control and CoQ10 (p<0.05). TBARS production in platelet rich plasma was significantly decreased in the groups with CoQ10 and green tea compared with the control and statin groups (p<0.05). TBARS of liver was significantly decreased in the group with green tea compared with the statin group (p<0.05). In the present study, even a high dose of statin did not show a cholesterol lowering effect, therefore depletion of CoQ10 following statin treatment in rats is not clear. More clinical studies are needed for therapeutic use of CoQ10 as an antioxidant in prevention of degenerative diseases independent of statin therapy.  相似文献   
33.
报告12例疸性腔皮病患者的性别与年龄构成、并发症、实验室检查、治疗经过和结果,对该病的病因、治疗和预后进行了讨论。  相似文献   
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35.
BACKGROUND CONTEXT: Spinal manipulation (SM) is a form of manual therapy used clinically to treat patients with low back and neck pain. The most common form of this maneuver is characterized as a high-velocity (duration <150 ms), low-amplitude (segmental translation <2 mm, rotation <4 degrees , and applied force 220-889 N) impulse thrust (high-velocity, low-amplitude spinal manipulation [HVLA-SM]). Clinical skill in applying an HVLA-SM lies in the practitioner's ability to control the duration and magnitude of the load (ie, the rate of loading), the direction in which the load is applied, and the contact point at which the load is applied. Control over its mechanical delivery is presumably related to its clinical effects. Biomechanical changes evoked by an HVLA-SM are thought to have physiological consequences caused, at least in part, by changes in sensory signaling from paraspinal tissues. PURPOSE: If activation of afferent pathways does contribute to the effects of an HVLA-SM, it seems reasonable to anticipate that neural discharge might increase or decrease in a nonlinear fashion as the thrust duration approaches a threshold value. We hypothesized that the relationship between the duration of an impulsive thrust to a vertebra and paraspinal muscle spindle discharge would be nonlinear with an inflection near the duration of an HVLA-SM delivered clinically (<150 ms). In addition, we anticipated that muscle spindle discharge would be more sensitive to larger amplitude thrusts. STUDY DESIGN/SETTING: A neurophysiological study of spinal manipulation using the lumbar spine of a feline model. METHODS: Impulse thrusts (duration: 12.5, 25, 50, 100, 200, and 400 ms; amplitude 1 or 2 mm posterior to anterior) were applied to the spinous process of the L6 vertebra of deeply anesthetized cats while recording single unit activity from dorsal root filaments of muscle spindle afferents innervating the lumbar paraspinal muscles. A feedback motor was used in displacement control mode to deliver the impulse thrusts. The motor's drive arm was securely attached to the L6 spinous process via a forceps. RESULTS: As thrust duration became shorter, the discharge of the lumbar paraspinal muscle spindles increased in a curvilinear fashion. A concave-up inflection occurred near the 100-ms duration eliciting both a higher frequency discharge compared with the longer durations and a substantially faster rate of change as thrust duration was shortened. This pattern was evident in paraspinal afferents with receptive fields both close and far from the midline. Paradoxically, spindle afferents were almost twice as sensitive to the 1-mm compared with the 2-mm amplitude thrust (6.2 vs. 3.3 spikes/s/mm/s). This latter finding may be related to the small versus large signal range properties of muscle spindles. CONCLUSIONS: The results indicate that the duration and amplitude of a spinal manipulation elicit a pattern of discharge from paraspinal muscle spindles different from slower mechanical inputs. Clinically, these parameters may be important determinants of an HVLA-SM's therapeutic benefit.  相似文献   
36.
目的 研究雌激素(ER)、孕激素(PR)及癌基因(cerbB-2)、凋亡抑制基因(Bcl-2)在子宫腺肌症病变中的表达和子宫腺肌症发病的相关性。方法 用免疫组化方法检测40例子宫腺肌症病变组织中ER及其他生物学指标的表达。结果 ER、PR与CerbB.2、Bcl-2在子宫腺肌症病变中均有不同程度的阳性表达,子宫肌层异位内膜ER阳性表达率97.5%,PR阳性率97.5%,cerbB-2阳性率82.5%,Bcl-2阳性率62.5%。在位内膜和异位内膜ER、PR均呈阳性,阳性率比较差异无统计学意义(P〉0.05)。异位内膜cerbB-2的强阳性率高于在位内膜,差异有统计学意义(P〈0.05)。ER、PR与cerbB-2、Bcl-2阳性率相比具有相关性(P〈0.05)。结论 ER、PR与cerbB.2、Bcl-2在异位内膜高表达,提示这些生物学指标在子宫腺肌症发生发展中发挥作用。  相似文献   
37.
OBJECTIVE: To evaluate the factors that influence the outcome of bronchial arterial embolisation (BAE) in chronic tuberculosis (TB). In cases of chronic TB, non-bronchial systemic arteries (NBSA) provide a significant source of massive or recurrent haemoptysis. DESIGN: Medical records and radiological findings of 30 consecutive TB patients who underwent BAE were retrospectively analysed and compared with those of 19 bronchiectasis patients. RESULTS: Chronic TB patients had higher numbers of total feeding vessels (4.40 +/- 3.85 vs. 1.79 +/- 1.51, P = 0.007) and NBSA (1.57 +/- 1.63 vs. 0.42 +/- 0.61, P = 0.005) than the bronchiectasis patients. The number of embolisations required for obliterating feeding vessels (3.87 +/- 2.48 vs. 1.95 +/- 1.47, P = 0.004), and the incidence of incomplete embolisation (30% vs. 5.3%, P = 0.033) were also higher in the TB patients. Moreover, recurrence after BAE was more frequent in the TB patients (17/30, 56.7% vs. 5/19, 26.3%, P = 0.037). Male sex, past history of haemoptysis and incomplete embolisation during BAE were associated with higher recurrence of haemoptysis in chronic TB patients. The existence of a fungus ball or significant pleural thickening (>/=10 mm) was not found to influence the recurrence rate of haemoptysis. CONCLUSION: The haemoptysis recurrence rate was higher in chronic TB than in bronchiectasis; this was found to be related to incomplete feeding vessel embolisation.  相似文献   
38.
OBJECTIVES: This study sought to characterize epileptic phenotypes in children with nonspecific mitochondrial disease (MD) and to evaluate MD diagnostic approaches. METHODS: A retrospective analysis of the medical, electroencephalogram, and laboratory records of 142 patients with epilepsy was performed. The patients were evaluated for MD, and 124 patients were included in the final cohort. The MD criteria used included an oral glucose lactate stimulation test (OGLST) and urine organic acid/plasma amino acid (UOA/PAA) assays as metabolic indicators of modified Walker criteria, as suggested by Bernier et al. (Neurology 59:1406-1411, 2002). RESULTS: Twenty-two patients were classified as having definite MD (9), probable MD (5), possible MD (6), or pyruvate dehydrogenase (PDH) deficiency (3), including one patient which showed a respiratory chain (RC) defect and PDH deficiency. Seven out of eight patients in whom significant RC defects were observed showed complex I defects. In 14 patients, epileptic seizures start at infantile ages. Of 17 patients who substantially presented generalized seizures, 4 patients started with partial seizures. Five patients consistently presented only partial seizures. The OGLST and UOA/PAA assays were useful for a more precise diagnosis of MD, although low positive predictive value of the OGLST was regrettable. No patient was classified as definite MD by Walker's original criteria, but the use of our revised MD criteria resulted in the classification of nine additional patients as definite MD. CONCLUSIONS: MD manifested considerable diverse epileptic phenotypes and should be considered in the differential diagnosis of epilepsy in children with unexplained encephalomyopathy and progressive and fluctuating clinical courses.  相似文献   
39.
目的观察鼻窦内镜术(endoscopic sinu ssurgery,ESS)对慢性鼻窦炎伴支气管哮喘患者哮喘发作的影响。方法对210例慢性鼻窦炎患者施行ESS术,其中伴有支气管哮喘病史者42例(20.0%)。210例患者均于术前、术后采用酶联免疫吸附测定法(ELISA)检测外周血单个核细胞(PBMC)培养上清液中的白细胞介素4(IL-4),干扰素γ(IFN-γ),可溶性白细胞介素2受体(sIL-2R)和可溶性IgE低亲和力受体(solube CD23,sCD23)的含量,并与20例正常对照组进行比较。通过主观和客观标准评定42例患者哮喘发作及对皮质类固醇的耐受状况,并对术后患者进行为期1年(10例)和3年(32例)的随访。结果鼻窦炎合并支气管哮喘患者术前PBMC培养上清液中IL-4,sIL-2R、sCD23含量较对照组显著升高,而IFN-γ含量较对照组显著减少。术后IL-4、sIL-2R、sCD23含量较对照组显著降低,而IFN-γ含量显著增高。术后哮喘改善水平由随访术后1年的45%提高到术后3年的70%。42例中32例(76%)哮喘发作次数明显减少,术前长期服用类固醇的2l例中,14例(67%)减少了对口服类固醇的使用。结论ESS对慢性鼻窦炎伴支气管哮喘患者的治疗有较满意的远期疗效。ESS能调节IL-4、IFN-γ sIL-2R、sCD23水平,降低哮喘的发作频率和对类固醇的依赖。  相似文献   
40.
A small proportion of thymoma patients without myasthenia gravis (MG) have been observed to develop MG after total removal of the thymoma. However, the underlying cause is not yet known due to the rarity of postoperative MG patients. We report a 39-year-old man in whom MG appeared after surgical removal of a thymoma. Computed tomography and magnetic resonance imaging showed no signs of recurrent or metastatic thymoma. Administration of pyridostigmine bromide resulted in the prompt improvement of myasthenic symptoms. Our observations indicate that postoperative follow-up care with monitoring of possible postoperative MG is necessary after resecting a thymoma.  相似文献   
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