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1.
The visual pursuit test is a method that collects and analyzes the characteristics of pursuit eye movements and examines the function of the eye movement system. This paper analyzes the model parameters of the smooth pursuit eye movement system in order to explore a method for improving the analysis. The input-output relationship of the smooth pursuit system can be expressed by a quasilinear model. We compute the model parameters (gain, phase, spectral purity, cross covariance) by digital signal processing. Eye movement is recorded by electrooculogram. Both eyes are tested individually. The visual target moves at frequencies of 0.2, 0.4, 0.8, 1.2, and 1.6 Hz. Ranges are gain, 1.01 to 0.70; phase, -0.1 ° to -66 °; spectral purity, 0.97 to 0.70; and cross covariance, 0.99 to 0.26. We tested 40 normal subjects as well as patients with ataxia (8), vertigo (18), and ophthalmoplegia (9). The oculomotor system of normal subjects functions as a linear system in the performance of this test at 0.2 to 0.8 Hz. The spectral purity dropped to about 0.70 at 1.6 Hz. The variability of all measures increases greatly at 1.6 Hz, which indicates that this target motion exceeds the tracking ability of many normal subjects and that the oculomotor system of normal subjects functions as a nonlinear system in this condition. Statistical tests show no significant differences between sex, age, and the two eyes. The model parameters tentatively proved effective in clinical application.  相似文献   
2.
Nasopharyngeal carcinoma (NPC) is a tumor derived from epithelial cells and Epstein-Barr virus infection has been reported to be a cause of this disease. Chemokine receptor CXCR4 was found to be involved in HIV infection and was highly expressed in human malignant breast tumors and the ligand for CXCR4, CXCL12 (SDF-1), exhibited high expression in organs in which breast cancer metastases are often found. The metastatic pattern of NPC is quite similar to that of malignant breast tumors. In this study, we investigated the expression of CXCR4 in nasopharyngeal carcinoma (NPC) tissues by immunohistostaining. We found different staining patterns, which included localization in the nucleus, membrane, cytoplasm or a combination of them. The staining intensity was also variable among samples. The metastatic rates in patients with high compared to low or absent expression was 38.6% versus 19.8%, respectively (P = 0.004). High expression of CXCR4 was associated with poor overall survival (OS = 67.05% versus 82.08%, P = 0.0225). These results suggest that CXCR4 may be involved in the progression of NPC and that a high level of CXCR4 expression could be used as a prognostic factor.  相似文献   
3.
目的了解不同人群的霍乱杀弧菌抗体水平和对霍乱的免疫状态,并探讨补体溶菌试验检测技术的应用价值。方法采用补体溶菌试验方法检测不同人群杀弧菌抗体水平,并运用统计学方法,对补体溶菌试验与常规分离培养法的检测结果进行分析。结果确诊病人的抗体水平显著高于当地健康人群(P〈0.001);补体溶菌试验方法与常规分离培养法检测结果差异无统计学意义(P〉0.05)。结论补体溶菌试验法在基层霍乱检测工作中具有一定的应用价值,为霍乱的免疫学和流行病学研究提供了依据。  相似文献   
4.
目的探讨紫杉醇联合草酸铂、卡培他滨三药方案治疗晚期转移性鼻咽癌的疗效及不良反应。方法2002年1月至2005年1月,110例晚期转移性鼻咽癌病人入组:试验组55例患者.第1天应用紫杉醇135mg/m^2、草酸铂130mg/m。静脉滴注,口服卡培他滨1650mg/m^2/d,连服l-14d,每3周为一个周期,连用2-4个周期;对照组55例患者,第1-5天应用DDP 20mg/m^2、5-Fu 0.5g/m^2静脉注射,3周为一个周期,连用2-4个周期;治疗结束2-4周后评价疗效。结果试验组疗效可评价55例,对照组疗效可评价53例。试验组与对照组有效率分别为(CR+PR)50.9%(28例)和32.1%(17例),两者差异有统计学意义(P〈0.05)。试验组和对照组中位生存时间为10.6个月和8.6个月,两者差异有统计学意义(t〈0.05)。安全性方面:试验组Ⅳ反应主要为手足综合征8例(14.5%)、骨髓抑制2例(3.6%)和消化道毒性4例(7.3%);对照组Ⅳ反应主要为消化道毒性8例(15.1%)、骨髓抑制2例(3.8%)。结论紫杉醇联合草酸铂、卡培他滨三药方案对晚期转移性鼻咽癌的疗效较DDP+5-Fu有优势,且不良反应可以耐受。  相似文献   
5.
目的 探讨口服长春瑞滨联合卡培他滨治疗葸环类、紫杉类耐药的转移性乳腺癌的疗效及不良反应。方法 80例确诊葸环类、紫杉类耐药的转移性乳腺癌患者随机分为两组。口服长春瑞滨联合希罗达组(试验组):40例患者口服江苏豪森酒石酸长春瑞滨软胶囊45.50mg/(m^2-d),第1、8、15天服用,口服卡培他滨1650mg/(m^2·d),连服1—14d,每3周为1个周期,连用4个周期。注射长春瑞滨联合希罗达组(对照组):40例患者,长春瑞滨(江苏豪森)25mg/(m^2·d)第1、8天静脉滴注,口服卡培他滨1650mg/(m^2·d),连服1-14d,每3周为1个周期,连用4个周期。治疗结束2周后评价疗效。结果 入组患者80例均可评价疗效,试验组有效率为42.5%,1年生存率为45.0%,中位进展时间4.7月,中位生存时间11.0月;对照组有效率为37.5%,1年生存率为42.5%,中位进展时间4.6月,中位生存时间10.6月;两组比较差异无统计学意义(P〉0.05)。在毒副反应方面,Ⅲ/IV便秘、局部静脉炎、HB下降、WBC下降、ANC下降、总Ⅲ/IV反应率两组比较。差异均有统计学意义(P〈0.05)。结论 口服长春瑞滨联合卡培他滨治疗葸环类、紫杉类耐药的转移性乳腺癌与静脉剂型疗效一致,并且在毒副反应上,口服长春瑞滨明显较静脉剂型轻,并且应用方便。  相似文献   
6.
目的探讨恩替卡韦联合水飞蓟宾对慢性乙型病毒性肝炎患者肝功能及肝纤维化的影响。方法 200例慢性乙型病毒性肝炎患者依据治疗方式的不同分为两组各100例,观察组使用恩替卡韦联合水飞蓟宾治疗,对照组使用恩替卡韦治疗,比较两组的肝功能和肝纤维化指标。结果治疗6个月后,两组的ALT、 TBil、 AST、 HA、 IVC、 LN水平均显著低于治疗前,且观察组显著低于对照组(P <0.05)。结论恩替卡韦联合水飞蓟宾治疗慢性乙型病毒性肝炎患者能够有效缓解肝纤维化损伤,改善肝功能。  相似文献   
7.
肝细胞癌合并胆管癌栓是肝癌的一种特殊类型,发生率为0.5%~2.5%,疾病进展快、预后差,目前国内外尚无相关的诊断与治疗共识,造成该疾病的治疗极不规范。中国医师协会肝癌专业委员会基于国内外本领域研究获得的循证医学证据,并结合我国临床实践,制订《肝细胞癌合并胆管癌栓多学科诊治中国专家共识(2020版)》。该共识针对肝细胞癌合并胆管癌栓的临床表现、诊断及分型、外科治疗、辅助治疗以及其他局部、区域性和系统性治疗进行系统阐述,旨在规范、普及和提高对肝细胞癌合并胆管癌栓的诊断和多学科治疗水平,改善该疾病总体预后。  相似文献   
8.
Objective  Ovarian dysgerminoma is an uncommon ovarian malignancy, Its clinicai features are special and there are many factors affecting its prognosis. If treated properly, the patient can be cured. Otherwise it may endanger the patient’s life. The aim of this study is to investigate the clinical features and factors related to prognosis of ovarian dysgerminoma. Methods  Data from 57 patients with pure ovarian dysgerminoma were analyzed retrospectively. The patients were admitted to the Cancer Center, Sun Yat-sen University from January 1.1964 to December 31, 2000. Results  The main clinical features were abdominal mass (56.1% ), abdominal pain (21.1% ), abdominal swelling (17.5%.), vaginal bleeding (5.3% )and genital tract abnormalities (5.3%). Twenty-six patients had stage I diseases, 8 stage II.9 stage III.1 stage IV and 13 recurrent and persistent diseases. The uterus was involved in 41.2% of patients with stage II -III diseases. Combined modality was given to 52 cases and a single-method treatment to 5 cases. The total overall 5 and 10-year survival rates for stages I-IV was 80.1 % and 70.0% respectively. The 5-year survival rate for stage I was 100%, stage II 55.2%. stage III 55.6% and stage IV 0%; for recurrent and persistent diseases, 72.7%. The stage I group of 12 patients. received adnexectomy and 14 patients underwent hysterectomy and adnexa removal. There was no significant difference between the 5 and 10-year survival rates (all 100%). Of the 23 patients in the stage I group to whom oniy chemotherapy was given after operation, 19 cases received 3 or more courses and were well without recurrence; 4 patients received only one course and one of them recurred 21 months after the operation. In the group of stages II and III cases, the 5-year survival rate was 86.7% for those whose chemotherapy courses were 3≥ 4 and 25.0% for patients who received less than 4 courses of chemotherapy (P<0.05). Conclusions  The prognosis of ovarian dysgerminoma is closely related to the disease stage and treatment modality. A fertility-preserving operation can be considered in early -staged patients, but caution needs to be exercised in the middle to late staged cases. Good results can be achieved with an operation-based combined modality in recurrent patients.  相似文献   
9.
THEINTRACELLULARFORMOFEPSTEINBARRVIRUSGENOMEINNASOPHARYNGEALCARCINOMAWangHuimin1汪慧民ChenJun1陈军ZengMusheng1曾木圣LiManzhi1李满枝Jia...  相似文献   
10.
A CLINICAL STUDY ON PROSTATE CANCER DIAGNOSIS WITH cDNA MACROARRAY   总被引:1,自引:0,他引:1  
Objective: To diagnose prostatic cancer (CAP) with cDNA macroarray. Methods: Total RNA was isolated from patients with prostate cancer and from normal people, and poly(A) RNA was further purified. Then differentially expressed genes were analysed in CaP and normal prostate by cDNA macroarray system. Results: There were differential expressions of nine prostate-associated specific genes in CaP as compared with normal prostate, among which, 7 were significantly up-regulated and 2 were down-regulated. Conclusion: As a diagnostic approach at molecular level, the cDNA macroarray is supposed to elevate the detection rate of CaP.  相似文献   
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