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51.
AIMS--To determine whether immunohistochemical evaluation of the abatement of proliferating cells after a first course of radiotherapy could predict the final response to treatment in oral squamous cell carcinoma (SCC). METHODS--Frozen sections from 31 cases of histologically confirmed oral SCC were stained with the monoclonal antibody Ki67 at diagnosis and after 10 Gy of radiotherapy. The percentage difference of Ki67 positive cells among the biopsy specimens taken at the beginning and after 10 Gy was correlated with the clinical response obtained at the end of the treatment and its significance determined. RESULTS--The percentage of Ki67 positive cells at diagnosis had no significant correlation with the final therapeutic result of radiotherapy. By contrast, the 32% difference of proliferating cells after 10 Gy of radiotherapy significantly differentiated responders from non-responders (p < 0.05). Furthermore, the abatement of the growth fraction after 10 Gy of radiotherapy was significantly correlated with the complete response (p < 0.01). CONCLUSIONS--These data show that the immunohistochemical evaluation of the abatement of Ki67 positive cells after 10 Gy of radiotherapy provides an independent variable of responsiveness to radiotherapy, allowing a reliable prediction of the final therapeutic result to be made.  相似文献   
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Linear scleroderma "en coup de saber" (LSCS) deformity is a subgroup of scleroderma characterized by unilateral atrophy and depression above the level of the eyebrow. In rare cases where it involves the whole unilateral face it can be mistaken with Parry-Romberg syndrome. Involvement of the trunk and extremities together with facial lesions has been extremely rare in the literature. We report an unusual case of linear scleroderma "en coup de sabre" where there is concomitant involvement of the ipsilateral side of the trunk and lower extremity. The patient's facial deformity is reconstructed with a polyethylene implant.  相似文献   
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Observations made in two patients and a review of the literature confirm the occurrence of a 5q- chromosome anomaly in lymphoproliferative disorders of both T and B cell type. Additional chromosome changes were invariably present and are of the "lymphoid" type. The chromosome morphology of the 5q- is indistinguishable from that found in myeloid disorders.  相似文献   
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Tungsten trioxide/graphene oxide (WO3/GO) nanocomposites have been successfully synthesized using in situ and ex situ chemical approaches. Graphite and tungsten carbide (WC) were employed to perform in situ synthesis, and WO3 and GO were employed to perform the ex situ synthesis of WO3/GO nanocomposites. GO, which was required for ex situ synthesis, is synthesized via the modified and improved Hummers method. XRD, SEM/EDS, and FTIR are used for the characterization of the nanocomposite. From the XRD of the WO3/GO nanocomposites, it was observed that WO3 distributed uniformly on graphene oxide sheets or was incorporated between the sheets. The photocatalytic activities of WO3/GO nanocomposites were evaluated by methylene blue (MB) adsorption and visible light photocatalytic degradation activities by UV-vis spectroscopy. The results showed that the efficiency of the photocatalytic activity of the nanocomposite depends on different synthesis methods and the morphology resulting from the changed method. WO3/GO nanocomposites synthesized by both methods exhibited much higher photocatalytic efficiencies than pure WO3, and the best degradation efficiencies for MB was 96.30% for the WO3/GO in situ synthesis nanocomposite.  相似文献   
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Background  

Burr-hole drainage has become the accepted treatment of choice for chronic subdural haematoma (cSDH), although still burdened with a major recurrence rate. The current analysis was initiated to determine management-related risk factors for recurrence, i.e. postoperative low-molecular-weight heparin thromboprophylaxis, and the importance of rinsing the subdural space.  相似文献   
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OBJECTIVE: To determine whether pulmonary vascular bed contributes to the development of in situ thrombosis and vascular remodelling in secondary pulmonary hypertension (SPH) via changes in its local secretory activities. METHODS: Seventy-one patients with the diagnosis of secondary pulmonary hypertension (38 females, mean age 40.36+/-1.05 years) were included in the study. Selective right and left heart catheterization was performed to each patient for diagnostic purposes. Blood samples obtained from left ventricle (LV) and pulmonary artery (PA) of each patient were analyzed for levels of plasminogen activator inhibitor-1 (PAI-1), platelet derived growth factor (PDGF), vascular endothelial growth factor (VEGF), D-dimer, von Willebrand factor (vWF), protein-C, antithrombin-III, fibrinogen, and plasminogen. Results were compared between LV and PA. Correlation analysis between each parameter and mean pulmonary artery pressure (MPAP) was performed. RESULTS: Although mean level of VEGF in LV and PA were found to be in normal range, it was significantly higher in LV than in PA (p<0.001). Mean PDGF and D-dimer levels, which remained in normal range were also higher in LV (p<0.001 and p<0.001, respectively) than in PA;.vWF showed similar degree of elevation in both LV and PA. Only one parameter, PAI-1, was found to be significantly higher in PA than in LV (p=0.012). Antithrombin-III, protein C, plasminogen, and fibrinogen levels showed no significant differences between two chambers. They also remained in normal range, except for fibrinogen, which was slightly elevated in both LV and PA. Correlation analysis revealed strong positive correlation between D-dimer level in both LV and PA and MPAP (r=0.775, p<0.001 and r=0.649, p<0.001, respectively). CONCLUSION: In SPH, pulmonary vascular bed shows increased thrombotic, hypofibrinolytic, and proliferative activities, which are partially related to the severity of illness.  相似文献   
60.
From October 2000 through April 2001, we prospectively evaluated the flow characteristics of the left internal thoracic artery (LITA) graft in a homogenous group of 44 men with isolated severe proximal left anterior descending coronary artery stenosis who underwent elective coronary artery bypass grafting with cardiopulmonary bypass. We performed transthoracic color Doppler ultrasonography preoperatively and repeated this examination in each patient between the 5th and 7th postoperative days, obtaining cross-sectional area, total flow volume, diastolic velocity, systolic velocity, mean velocity, pulsatility index, and resistance index. These results were compared with those of the intraoperative free-bleeding technique. Good-quality Doppler images of the LITA were easily obtained with a combined supraclavicular-parasternal approach. After surgery, systolic flow velocity, pulsatility index, and resistance index decreased significantly, but diastolic flow velocity and mean flow velocity increased significantly. The intraoperative flow volume obtained by the free-bleeding technique (32.42 +/- 12.33 mL/min) was significantly less than both pre- and postoperative ultrasonographic values (42.22 +/- 10.77 mL/min and 45.36 +/- 19.52 mL/min, respectively). No significant difference was found when changes in LITA values were compared between patients with (n=19) and without (n=25) normal anterior wall motion. We conclude that color Doppler ultrasonography is a reliable noninvasive technique for preoperative evaluation of the LITA as a graft and for postoperative long-term follow-up of graft function. However the intraoperative free-bleeding technique is not reliable for flow-volume measurement due to anesthesia-related hemodynamic changes and vasospasm. Color Doppler can prevent useless LITA harvesting and decrease the need for postoperative LITA angiography.  相似文献   
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