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81.
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   
82.
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   
83.
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   
84.
抑肽酶预处理防护大鼠肝脏缺血再灌注损伤的实验研究   总被引:5,自引:1,他引:4  
苏东  陶国才  李昆 《重庆医学》2002,31(8):709-710
目的 探讨抑肽酶预处理对肝脏缺血再灌注损伤的防护作用。方法 SD大鼠80只,随机分为抑肽酶预处理和生理盐水预处理两组,观察肝脏缺血再灌注损伤引起及抑肽酶预处理的影响。结果 拟肽酶预处理组大鼠缺血再灌注损伤引起的血清谷丙转氨酶(ALT),谷草转氨酶(AST)活性及肝组织丙二醛(MDA)含量变化均显著低于生理盐水预处理组(P<0.01);肝细胞形态学异常改变也明显较生理盐水预处理组轻。结论 抑肽酶预处理对大鼠肝脏缺血再灌注损伤有明显的防治作用。  相似文献   
85.
AIM: To evaluate the relationship between changes in serum transforming growth factor β1 (TGFβ1) level and curative effect of radiotherapy (RT) in patients with esophageal carcinoma.METHODS: Ninety patients with histologically confirmed esophageal carcinoma were enrolled. Serum samples for TGFβ1 analysis were obtained before and at the end of RT. An enzyme-linked immunosorbent assay was used to measure serum TGFβ1 level. Multivariate analysis was performed to investigate the relationship between disease status and changes in serum TGFβ1 level.RESULTS: Serum TGFβ1 level in patients with esophageal carcinoma before RT was significantly higher than that in healthy controls (P < 0.001). At the end of RT, serum TGFβ1 level was decreased in 67.82% (59/87) of the patients. The overall survival rate at 1,3 and 5 years was 48.28% (42/87), 19.54% (17/87)and 12.64% (11/87), respectively. Main causes of death were local failure and regional lymph node metastasis.In patients whose serum TGFβ1 level decreased after RT,the survival rate at 1, 3 and 5 years was 61.02% (36/59),28.81% (17/59) and 18.64% (11/59), respectively. The survival rate at 1 year was 17.86% (5/28) in patients whose serum TGFβ1 level increased after RT, and all died within 18 mo (P < 0.01).CONCLUSION: Serum TGFβ1 level may be a useful marker for monitoring disease status after RT in patients with esophageal carcinoma.  相似文献   
86.
87.
经颅彩色双功超声是一种新型、无创的超声诊断仪,高空间分辨率显示颅内血管和脑实质的结构,笔者查阅了近年来相关文献,主要综述经颅彩色多普勒血流显像在颅脑血管疾病中的诊断价值,同时讨论二维经颅超声的应用及新的实验性显像技术。  相似文献   
88.
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric cancer.  相似文献   
89.
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   
90.
目的:探讨急性重症胆管炎患者的手术时机和死亡原因。方法:回顾性分析23例急性重症胆管炎患者的治疗及预后情况。结果:死亡2例(手术死亡及传统治疗死亡各1例)。早期大剂量短期应用糖皮质激素患者休克得到纠正率85%,明显高于未用糖皮质激素患者休克纠正率50%。结论:急性重症胆管炎患者应在出现休克和(或)精神症状之前手术,对已出现休克的患者,应先给予充分的保守治疗,待病情稳定后再手术。贻误手术时机,严重合并症如多器官功能衰竭及高龄是死亡的主要原因。  相似文献   
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