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81.
Objective To observe the time course of changes in synaptophysin (P38) expression in the cortex and hippocampus of rats with posttraumatic epilepsy (PTE), and explore the role of synaptic plasticity in the epileptogenesis of PTE. Methods Thirty-seven male Sprague-Dawley rats were randomized into normal control group (n=5), sham-operated group (n=12) with intracortical saline injection, and PTE model group (n=20) with stereotactic FeCl<,2> injection (0.1 mol/L, 10 μ1) into the motor cortex. The expression of P38 in the brain cortex and hippocampus of the rats was detected immunohistochemically at 1 h and 7, 14 and 30 days after the injections. Results Most of the rats with FeCl<,2> injection developed isolated epileptiform discharges soon alter the injection. Compared with the sham-operated groups, the rats in PTE group showed significantly decreased P38 expression in the right frontal cortex at all the time points of measurement (P<0.05). At 1 h after FeCl<,2> injection, P38 expression in the polymorphic layer, stratum lacunosum and stratum radiatum of the right hippocampai CA3 area and DG molecular layer underwent no significant changes (P>05), but at 7 days, the expression increased significantly in all the stratum regions of the right hippocampal CA3 area, and this high expression level was maintained till 30 days after the injection. Conclusion Synaptic plasticity alterations in relation to P38 expression changes in the cortex and hippocampus may play an important role in the epileptogenesis of PTE in this rat model.  相似文献   
82.
AIM: To compare bacillus Calmette-Guerin (BCG) with epirubicin in adjuvant therapy of superficial bladder transitional cell carcinoma, with respect to recurrence, progression and survival. Prognostic factors are also evaluated. METHODS: Between October 1991 and September 1999, all patients harboring superficial bladder cancers (Ta or T1) with any of the relevant criteria (stage>a, grade>1, size>1 cm, multiple or recurrent tumors), after complete transurethral resection were randomized to receive either 81 mg Connaught strain BCG or 50 mg epirubicin. Patients with recurrences were eligible to crossover, even repeatedly, until progression. Recurrence, progression and survival were analyzed in relation to initial treatment, patient characteristics and tumor characteristics. RESULTS: There were 209 patients included in the study, 149 men and 60 women. The mean age was 69.9 years (range, 24-92). The BCG group consisted of 102 patients and the epirubicin group contained 107 patients. Final analysis was made at a median follow up of 23, 47 and 61 months for recurrence, progression and survival, respectively. The 10-year Kaplan-Meier estimates for recurrence-free, progression-free and disease-specific survival were 61%, 78% and 80%, respectively, for the BCG group. The corresponding figures were 32%, 74% and 92%, respectively, for the epirubicin group. Time to recurrence differed significantly between two treatment groups (P=0.0004). Multiplicity increased the risk of recurrence, while grading influenced recurrence, progression and disease specific survival. CONCLUSIONS: Bacillus Calmette-Guerin prolonged time to recurrence when compared with epirubicin. Grading was shown to be a universal prognostic factor for recurrence, progression and disease specific survival.  相似文献   
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84.
The development of thrombolytic and neuroprotective agents for the treatment of acute stroke has created an imperative for improved imaging techniques in the assessment of acute stroke. Five cases are presented to illustrate the value of perfusion CT in the evaluation of suspected acute stroke. To obtain the perfusion data, a rapid series of images was acquired without table movement following a bolus of contrast medium. Cerebral blood flow, cerebral blood volume and mean transit time were determined by mathematically modelling the temporal changes in contrast enhancement in the brain and vascular system. Pixel‐by‐pixel analysis allowed generation of perfusion maps. In two cases, CT‐perfusion imaging usefully excluded acute stroke, including one patient in whom a low‐density area on conventional CT was subsequently proven to be tumour. Cerebral ischaemia was confirmed in three cases, one with an old and a new infarction, one with a large conventional CT abnormality but only a small perfusion defect, and one demonstrating infarct and penumbra. Perfusion CT offers the ability to positively identify patients with non‐haemorrhagic stroke in the presence of a normal conventional CT, to select those cases where thrombolysis is appropriate, and to provide an indication for prognosis.  相似文献   
85.
This retrospective study aimed to provide data on the prevalence, epidemiology and etiology of the knee articular cartilage lesions and describe and estimate, on the ground of a large database, the number of patients who might benefit from cartilage repair surgery. The analysis of 25,124 knee arthroscopies performed from 1989 to 2004 was conducted. Information concerning cartilage lesion, associated articular lesions and performed procedure were collected. Cartilage lesions were classified in accordance with the Outerbridge classification. Chondral lesions were found in 60% of the patients. Documented cartilage lesions were classified as localized focal osteochondral or chondral lesion in 67%, osteoarthritis in 29%, osteochondritis dissecans in 2% and other types in 1%. Non-isolated cartilage lesions accounted for 70% and isolated lesions accounted for 30%. The patellar articular surface (36%) and the medial femoral condyle (34%) were the most frequent localization of the cartilage lesions. Grade II according to Outerbridge classification was the most frequent grade of the cartilage lesion (42%). The most common associated articular lesions were the medial meniscus tear (37%) and the injury of the anterior crucial ligament (36%). Articular cartilage lesions are a common pathology of the knee joint. The potential candidates for cartilage repair surgery, patients with one to three localized grade III and IV cartilage lesions, under the age of 40 were found in 7% and under the age of 50 years in 9% of all analysed patients. However, because these patients are a heterogeneous group and the natural history of cartilage lesions remains so far unknown, also the total number of patients in our study, who might benefit from cartilage repair, remains unknown precisely.  相似文献   
86.
<正>电子结肠镜检查是诊断和筛查肠道疾病常用、有效的检查方法之一,而进行结肠镜检查的基本条件是清洁良好的肠道准备。虽然近年来肠道清洁剂的商品化和肠道准备方法的标准化不断完善,但仍有约30%的患者肠道准备不充分[1-3]。不充分的肠道准备会导致检查时间延长、操作难度增加、病变检出率降低、漏诊及检查费用增加等。肠道准备的质量多与患者的依从性有关,加强对患者肠道准备相关知识的教育,增强患者对肠道准备方法的认识和理解,可以提高检查前的肠道准备质量[4  相似文献   
87.
Platelets are known to become activated during storage, but it is unclear whether such activation affects recovery or survival after platelet concentrate (PC) transfusion. With the use of flow cytometry to determine the percentage of platelets expressing the alpha-granule membrane protein 140 (GMP-140), a known adhesive ligand appearing on the platelet surface after activation, several studies were conducted. These investigations evaluated 1) the occurrence of significant platelet activation over time in PCs (n = 46) stored under standard blood bank conditions; 2) the correlation between platelet activation and platelet recovery in normal subjects after PC storage (n = 12), as assessed by the recovery of Indium-labeled platelets; and 3) the recovery of activated and unactivated platelets in thrombocytopenic cancer patients transfused with standard PCs (n = 11). It was determined 1) that an increasing duration of storage of PC was associated with increasing platelet activation as measured by the percentage of platelets expressing GMP-140, progressing from a mean of 4 +/- 2 percent (SD) on the day of collection to a mean of 25 +/- 8 percent by 5 days of storage: 2) that, in normal subjects, posttransfusion recovery of autologous platelets stored for 2 to 4 days and then labeled with In111 was inversely correlated with the percentage of activated platelets in the transfused PC (r = -0.55, p = 0.05); and 3) that, when thrombocytopenic patients were transfused with standard PCs, the recovery of the activated platelets in the transfused PCs averaged only 38 +/- 15 percent of the number predicted by the absolute platelet increment.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
88.
89.
We have found that the addition of 10 mM inorganic phosphate to DHA in CPD-adenine maintains ATP levels at normal or higher than normal values for six weeks of storage. 2,3-DPG values are slightly lowered by the extra phosphate, but are still maintained at approximately half normal for four weeks by the DHA. The addition of a higher phosphate concentration, 20 mM, to DHA produced lower levels of ATP and 2,3-DPG than those observed with 10 mM phosphate, although both levels were better than in the CPD-adenine control. pH values in this experiment were lowest in the three preservatives containing DHA, probably indicating increased lactate production due to metabolism of this triose sugar, in addition to dextrose present in CPD.  相似文献   
90.
In an attempt to improve the poor outlook for children with T-cell leukemia (T-ALL), the Southwest Oncology Group, Pediatric Division, used a modified LSA2-L2 multidrug regimen to treat 53 patients with E- rosette-positive T-ALL. This regimen was chosen because of its demonstrated efficacy in T-cell (mediastinal) non-Hodgkin's lymphoma. Complete remission (CR) rate was 88%. Range of follow-up for those patients remaining in CR is 24-49 mo (median 39 mo). Life table analysis estimates that 40% (SE 8.3%) of all patients who started induction therapy will remain failure-free at 3 yr. For patients achieving CR, 46% (SE 9%) are projected to remain in both marrow and extramedullary CR at 3 yr. Median failure-free duration was 13 mo, but only 1 patient has relapsed beyond 16 mo. Twenty-nine percent of initial relapses were isolated CNS relapses. The following presenting factors did not relate significantly to outcome: hemoglobin, platelet count, uric acid, race, and mediastinal mass. Age greater than 10 yr was a poor prognosis indicator only in the less than 50,000/microliter WBC group. Sex was not a significant factor after adjusting for WBC. WBC was the most important prognostic factor: 19% (SE 8%) of patients with WBC greater than 50,000/microliter are projected to remain failure- free at 3 yr as compared to 67% (SE 11%) of patients with WBC less than 50,000/microliter. Although the overall results are better than those previously reported for pediatric patients with T-ALL, the long-term failure-free rate remains low for patients presenting with greater than 50,000/microliter WBC.  相似文献   
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