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71.
The primary issues addressed in this study were: (1) determination of the significance of the classification “good outcome” utilizing the Glasgow Outcome Scale (GOS) in children at least 1 year after brain injury; (2) detection of residual lesions of brain parenchyma in these children upon follow up MRI scans; and (3) detection of relationships between neuropsychological test performance and MRI results. Selection criteria included children 6–15 years of age at the time of testing who received an initial CT scan at the time of their head injury and who had been injured at least 12 months prior to the follow up test. Only children who did not demonstrate neurological disability at the time of follow up examination were selected. The children showed a status of “good outcome” as defined by the GOS. Neurological examination, neuropsychological tests and an MRI were done. The test results of 59 patients were compared to those of a matched control group. Children, after receiving head injuries, showed significantly poorer results with respect to cognitive, motor and fine motor skills. Of all MRI-scans 66% revealed pathological findings. Cortical lesions were detected on MRI in 14% of cases; subcortical injuries were detected in 12% and, deep white matter lesions in 31%. Furthermore, corpus callosum damage was observed in 26% of cases. Pathological MRI findings were also observed in children with mild head injuries. All of the children with normal MRI findings showed abilities comparable to those of children in the control group. Patients with cortical lesions exhibited only motor deficits, whereas motor and cognitive deficits were seen in patients with deep white matter lesions. Children with multiple lesions demonstrated test results in all variables 1 to 2 standard deviations below those of the control group. Conclusions Children suffering a brain injury who 1 year later are classified within the “good outcome” group according to the Glasgow Outcome Scale often have significant morphological and functional brain deficits. Received: 6 January 1996 /  Accepted: 10 August 1996  相似文献   
72.
T-lymphocyte cell function was studied in vitro in peripheral blood mononuclear cells (PBMC) from 61 male patients with head and neck squamous cell carcinomas compared to 46 control patients. Patients older than 80 years or with reduced tumor-related performance status as measured by Karnofsky score less than 75 were excluded. In contrast to previous similar studies, control subjects ensured a minimum stress load by sampling all patients on the day of either diagnostic or therapeutic surgery. PBMC were separated by density-gradient centrifugation and subsequently cultured with autologous sera in vitro. The mitogen concanavalin A (Con A), which stimulates all T-cell clones, was employed. Findings showed that increased Con A stimulation and PBMC proliferation occurred with PBMC from cancer patients compared to that from control patients. In contrast, no differences could be detected with respect to the stimulated supernatant level of interleukin-2, interleukin-4 or interferon-γ between the groups. These results suggest that T-lymphocytes from PBMC are generally affected by neoplastic disease through either a supporting cell or serum factor.  相似文献   
73.
普通额镜下鼻内激光泪囊鼻腔造孔术治疗慢性泪囊炎   总被引:11,自引:0,他引:11  
报告在普通额镜下以YAG激光经鼻腔行泪囊鼻腔造孔术,治疗慢性泪囊炎患者37例(45眼),经3~24个月的随访观察,泪道阻塞均解除,有效率为95.6%,治愈率为88.9%。本手术具有损伤小,操作简便,快捷,术后反应轻,并发症少等优点。并对手术方法及影响疗效的因素进行了探讨。  相似文献   
74.
头颈外科包括了头颈部肿瘤及相关疾病的诊断和治疗。香港头颈外科的起源可以追述到本世纪60年代中期。当时的香港大学玛丽医院外科学系主任王源美教授是开创这一领域的先驱。香港最初只有普外科医生涉及到这一区域肿瘤的治疗,经过多年来其它专科的发展,目前香港头颈部的疾病已经可以由三个外科次级专科处理,即耳鼻喉科、整形重建科和普外科。20年来,在外科、放射科及化疗科的共同努力下,头颈部肿瘤在诊断及治疗方面获得的迅速的发展,这就使病人的预后得到了很大程度的改善。  相似文献   
75.
Patients with head and neck cancers that produce a high concentration of granulocyte colony-stimulating factor (G-CSF) or patients with esophageal squamous cell carcinomas who have elevated serum interleukin-6 (IL-6) concentrations have been found previously to be at significant risk for tumor invasion to adjacent organs as well as frequent metastases. This suggests that G-CSF and Il-6 enhance the invasiveness and metastatic potential of cancer cells. We studied the in vitro invasiveness of head and neck cancer cell lines with and without recombinant human G-CSF (rhG-CSF) and human IL-6 (hIL-6) in an extracellular matrix membrane system. The degree of invasiveness was affected by incubating cells with hIL-6, but not by pre-incubating the cell-matrix with hIL-6. The maximum concentration of hIL-6 for enhanced invasiveness was approximately 5,000 u/ml. In addition, rhG-CSF enhanced the invasiveness of tumor cells that produced large amounts of G-CSF. The present study also suggests that tumor cells tend to invade and metastasize in an environment rich in hIL-6. Received: 3 November 1997 / Accepted: 1 April 1998  相似文献   
76.
Squamous cell carcinomas of the head and neck have been found to show a high expression of the receptor for epidermal growth factor (EGF). This overexpression of the receptor has been associated with malignant transformation of cells, although there is still debate as to what extent this receptor takes part in the proliferation of malignant cells and which function it fulfills. The factors which determine receptor-ligand interaction are also not clearly defined. That the extracellular domain of the EGF receptor carries carbohydrate or sialoglycan structures might be important for function of the receptor. Since tumor specific enzymes can possibly alter such structures, it was the aim of our study to investigate the role of these structures on the EGF receptor during the proliferation of head and neck carcinomas. We used the human laryngeal squamous carcinoma cell line HLaC 79 and altered, for the first time, specific glycan structures with sialidase α-2,3 and α-2,6, causing desialylation. Changes were also produced by endo-β-galactosidase and sialyltransferase. Findings were monitored by labeling with bromo-deoxyuridine. To determine receptor affinity, 125I-labeled EGF was employed. Results showed that both cell proliferation and receptor affinity depended on the level of sialylation of the receptor carbohydrate side chains. Desialylation led to a statistically significant reduction of tumor cell proliferation to 65 ± 33% (P < 0.01), while receptor affinity decreased to 70 ± 26% (P < 0.01).The importance of EGF receptor for the proliferation of malignant cells seems to depend on the level of sialylation of glycan structures on receptor protein. A release of enzymes by tumor cells may then produce auto-control of tumor proliferation on its own. Received: 5 November 1997 / Accepted: 21 April 1998  相似文献   
77.
78.
无法切除的复发头颈部鳞癌的姑息放疗   总被引:2,自引:0,他引:2  
为评价头颈部鳞癌术后复发患者行姑息放疗的疗效及其影响因素,对1988年7月至1996年2月在我科接受姑息放疗的106例患者的资料行回顾性分析。结果:放疗后CR22.6%(24/106),PR38.7%(41/106),NR38.7%(41/106);总有效率为61.3%(65/106);放疗后挽救性手术成功率为4/9;疗后63.2%(67/106)的患者Karnofsky得分上升,症状减轻,生存质量提高;1、2、3年生存率分别为54.7%(58/106)、21.7%(23/106)和5.7%(6/106);远处转移率29.2%(31/106),放疗并发症10.4%(11/106)。结论:姑息放疗是晚期头颈部鳞癌术后复发患者一种较好的治疗选择;为了提高疗效,放射剂量应尽可能高于50Gy,采用超分割连续放疗技术和避免分段。  相似文献   
79.
Positron emission tomography (PET) with fluorodeoxyglucose (FDG) allows the visualization of metabolic tissue activity. Use of FDG in in-vivo cancer imaging is based on enhanced glycolysis in tumor cells. In vivo experiments have demonstrated the potential use of FDG PET in squamous-cell head and neck tumors and the detection of tumor involvement in lymph nodes. Since its introduction in this area, several papers have appeared on the use of this imaging modality. Indications for the use of FDG PET in patients with head and neck cancer are discussed.  相似文献   
80.
Purpose: The purpose of the present study is to investigate the strength of association between anemia and overall survival, locoregional failure, and late radiation therapy (RT) complications in a large prospective study of patients with advanced head and neck cancer treated with conventional radiotherapy with or without a hypoxic cell sensitizer.

Methods and Materials: Between March 1988 and September 1991, 521 patients with Stage III or IV squamous cell carcinoma of the head and neck were entered into a randomized trial examining the addition of etanidazole (SR 2508) to conventional radiation therapy (RT) (66–74 Gy in 33–37 fractions, 5 days a week). Patients with hemoglobin (Hgb) levels measured and recorded prior to the second week of RT were included in this secondary analysis. Hemoglobin levels were stratified as normal (≥ 14.5 gm% for men, ≥ 13 gm% for women) or anemic (< 14.5 gm% for men, < 13 gm% for women). Locoregional failure rates were calculated using the cumulative incidence approach. Overall survival was estimated according to the Kaplan-Meier method. Late RT toxicity was scored according to the RTOG morbidity scale. Differences in rates of overall survival, locoregional failure, and late complications were tested by the Cox proportional hazard model.

Results: Of 504 eligible patients, 451 had a Hgb level measured and recorded prior to the second week of RT. One hundred sixty-two patients (35.9%) were considered to have a normal Hgb level and 289 patients (64.1%) were considered to be anemic. The estimated survival rate is 35.7% at 5 years in patients with a normal Hgb, versus 21.7% in anemic patients (p = 0.0016). The estimated locoregional failure rate is 51.6% at 5 years in patients with a normal Hgb, versus 67.8% in anemic patients (p = 0.00028). The estimated rate of grade 3 or greater toxicity is 19.8% at 5 years in patients with a normal Hgb, versus 12.7% in anemic patients (p = 0.063). On multivariate analysis, several variables were found to be independent predictors of survival including: T stage, Karnofsky performance status, N stage, age, total radiation dose to the primary, and Hgb level. Independent predictors of locoregional control included T stage, Karnofsky performance status, N stage, radiation dose, and Hgb level. The only variables which predicted for the development of late RT complications were gender (p = 0.0109) and age (p = 0.0167). These findings were consistent regardless of whether Hgb level was considered a dichotomous or continuous variable.

Conclusion: Low Hgb levels are associated with a statistically significant reduction in survival and an increase in locoregional failure in this large prospective study of patients with advanced head and neck cancer. Hgb level should be considered as a stratification variable in subsequent studies of head and neck cancer. Strategies to increase Hgb prior to RT in patients with head and neck cancer may lead to improved survival and loco-regional control.  相似文献   

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