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51.
急性轻中度缺氧条件下心率及收缩压变异性谱变化   总被引:3,自引:3,他引:3  
目的:应用心率及收缩压变异性(HRV、SBPV)谱分析方法评价急性轻中度缺氧条件下心血管自主神经调节的变化。方法:10名健康男性青年分别吸入氧13.7%(相当于海拔3500m)和11%(相当于海拔5000m)两种氮-氧混合气各20min,将对照和缺氧条件下的HRV和SBPV谱变化进行对比分析。结果:在两种缺氧条件下,受试者均出现血压下降、心率增快反应,HRV谱总功率(TP)和高频成分(HF)功率均显著减小,低频成分(LF)功率与LF/HF功率比值无显著变化,SBPV谱LF功率显著增大,3名缺氧耐力不良受试者尤为明显。不同水平缺氧之间的数值比较差异均无显著性意义。结论:急性轻中度缺氧条件下,人副交感神经抑制,交感神经兴奋,联合应用HRV与SBPV谱分析方法可对心血管自主神经调节活动进行评定;但HRV的LF成分变化机理较为复杂。  相似文献   
52.
A POSTOPERATIVE PROGNOSTIC NOMOGRAM FOR RENAL CELL CARCINOMA   总被引:8,自引:0,他引:8  
PURPOSE: Few published studies have combined prognostic factors to predict the likelihood of recurrence after surgery for renal cell carcinoma. We developed a nomogram for this purpose. MATERIALS AND METHODS: With Cox proportional hazards regression analysis, we modeled pathological data and disease followup for 601 patients with renal cell carcinoma who were treated with nephrectomy. Predictor variables were patient symptoms, including incidental, local or systemic, histology, including chromophobe, papillary or conventional, tumor size, and pathological stage. Treatment failure was recorded when there was either clinical evidence of disease recurrence or death from disease. Validation was performed with a statistical (bootstrapping) technique. RESULTS: Disease recurrence was noted in 66 of the 601 patients, and those in whom treatment was successful had a median and maximum followup of 40 and 123 months, respectively. The 5-year probability of freedom from failure for the patient cohort was 86% (95% confidence interval 82 to 89). With statistical validation, predictions by the nomogram appeared accurate and discriminating with an area under the receiver operating characteristic curve, that is a comparison of the predicted probability with the actual outcome of 0.74. CONCLUSIONS: A nomogram has been developed that can be used to predict the 5-year probability of treatment failure among patients with newly diagnosed renal cell carcinoma. The nomogram may be useful for patient counseling, clinical trial design and patient followup planning.  相似文献   
53.
PURPOSE: We determined long-term symptoms in patients after brachytherapy (radioactive seed implantation) for early (nonmetastatic) prostate cancer. MATERIALS AND METHODS: We performed a cross-sectional survey of 105 (80% of those contacted) men treated at least 2 years 9 months (median 5.2 years) previously with brachytherapy alone (72 patients) or brachytherapy plus external beam radiation therapy (33) at a pioneering referral center for ultrasound guided brachytherapy. RESULTS: Median patient age was 70 years at treatment and 75 years when surveyed. Bowel symptoms were uncommon (range 4% to 9%) unless patient had also received external beam radiation therapy. Urinary incontinence occurred in 45% of men, although leakage of more than a few drops, daily leakage and wearing absorptive pads occurred in 11%, 11% and 16%, respectively. Men who underwent documented transurethral prostatic resection were much more likely to report incontinence (83% versus 39%, p = 0.005) and those who underwent implantation less than 5 years earlier were less likely (33% versus 53%, respectively, p = 0.04). Complete impotence was common (50%) but impaired erections were more so (73%). Patients who received combined radiation treatment had more frequent erectile dysfunction. CONCLUSIONS: Long-term bowel symptoms are infrequent after brachytherapy alone. Urinary incontinence is common, although usually only a few drops and not daily. Erectile dysfunction, prevalent in populations of older men, was found in most men. However, because our study design precluded documenting baseline symptoms before treatment and subsequent clinical interventions, the contribution of factors other than brachytherapy is unclear. The morbidity of patients receiving more recent brachytherapy may be less.  相似文献   
54.
腹腔镜胆总管切开探查取石46例报告   总被引:1,自引:0,他引:1  
目的探讨腹腔镜胆总管切开探查取石、胆总管一期缝合的可行性及其微创价值。方法回顾分析我院46例腹腔镜胆总管切开探查取石的临床资料。腹腔镜下完成手术44例,其中胆总管切开探查取石胆总管一期缝合24例,胆总管切开探查取石胆总管T管引流20例;中转开腹胆总管切开取石T管引流2例。结果手术中无副损伤。手术后无胆漏及其它并发症发生。所有病例是治愈出院。32例术后随访3~12个月,未发现残余结石及胆道狭窄。结论腹腔镜胆总管切开探查取石、胆总管一期缝合是可行的,而且具有极大的微创优势。  相似文献   
55.
A new abnormal hemoglobin was observed in 15 members over four generations of a large Swiss family and has been termed "Hemoglobin Zürich."The discovery of this hemoglobin was prompted by a severe hemolytic crisisin two members of the family after sulfonamide therapy. During this episode,virtually all erythrocytes and reticulocytes contained a single large inclusionbody which was visible with Giemsa and brilliant cresyl blue stains. Outsidethe hemolytic episode, the erythrocytes revealed no morphologic abnormalities.The results of enzyme studies were all within normal limits. The associationof a hemoglobinopathy with a drug-induced inclusion body anemia withoutany demonstrable enzyme defect is a new entity. The anomalous hemoglobinis inherited as a dominant character and affects both sexes. Thus far, onlythe heterozygous form has been observed.

Submitted on April 9, 1962 Accepted on June 20, 1962  相似文献   
56.
 目的 应用蛋白质组学表面增强激光解吸电离-飞行时间-质谱(SELDI-TOF-MS)技术筛选淋巴瘤患者血清特异性生物标志物,发现淋巴瘤早期诊断与人群筛查的血清学特异性标志。方法 应用SELDI-TOF-MS技术检测96例淋巴瘤患者血清特异性标志物,包括非霍奇金淋巴瘤(NHL)86例,霍奇金淋巴瘤(HL)10例,以30名健康体检者作为对照。采用生物化学法测定乳酸脱氢酶(LDH),酶联免疫吸附法(ELISA)测定可溶性白细胞介素-2受体(sIL-2R)、β2-微球蛋白(β2-MG)和糖链抗原125(CA125)。结果 在质荷比(M/Z)为0.2~16.0间,NHL患者有15个蛋白质含量与健康人差异有统计学意义(P<0.01),其中M/Z为 6880、8564、8692和13 751的蛋白质低表达对淋巴瘤的敏感度与特异度高,灵敏度和特异度分别为82.29 %和80.00 %、78.13 %和73.30 %、75.00 %和80.00 %、71.88 %和83.30 %。4个蛋白质对淋巴瘤诊断的灵敏度与特异度差异均无统计学意义(P>0.05),4个蛋白质联合检测淋巴瘤特异度达100.00 %,与LDH的灵敏度21.74 %、CA125的灵敏度56.80 %、β2-MG的灵敏度70.50 %比较,差异均有统计学意义(P<0.05)。结论 对M/Z为6880、8564、8692和13 751的蛋白质行质谱检测,有望作为人群筛查、诊断淋巴瘤的血清学特异性标志。  相似文献   
57.
目的:验证二甲双胍治疗抗精神病药引起的血脂异常的疗效和安全性。方法:将两项随机、安慰剂的 对照研究纳入分析。共有201例服用抗精神病药物后出现血脂异常的首发精神分裂症患者,并将其分为1 000 mg/d 二甲双胍组(以下简称为二甲双胍组,n=103)和安慰剂组(n=98),观察24周。在基线、治疗后第12周和第24周进行 临床症状及体重、血糖、血脂等代谢指标的评估。结果:二甲双胍治疗后,二甲双胍组和安慰剂组之间低密度脂 蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)的平均差异从基线时的0.16 mmol/L,降低到第24周结束时的 –0.86 mmol/L,降低了1.02 mmol/L,差异有统计学意义(P<0.01)。而24周结束时,二甲双胍组LDL-C≥3.37 mmol/L的 患者有25.3%,显著低于安慰剂组24周结束时的64.8%(P<0.01)。与安慰剂组相比,二甲双胍组的体重、体重指数、 胰岛素、胰岛素抵抗指数、总胆固醇、三酰甘油和高密度脂蛋白胆固醇也有显著变化,差异均有统计学意义(均 P<0.05)。治疗对体重和胰岛素抵抗的影响出现在第12周,并且在第24周进一步改善,但对改善血脂异常的作用在第 24周结束时才出现。结论:二甲双胍治疗对于改善抗精神病药物引起的血脂异常和胰岛素抵抗是有效的,并且改善 抗精神病药物诱导的胰岛素抵抗出现的时间早于降低血脂异常的时间。  相似文献   
58.
We have used the long-term bone marrow culture (LTBMC) system to analyze hematopoiesis in three patients with dyskeratosis congenita (DC), two of whom had aplastic anemia, and the third had a normal blood count (apart from mild macrocytosis) and normal BM cellularity. Hematopoiesis was severely defective in all three patients, as measured by a low incidence of colony-forming cells and a low level of hematopoiesis in LTBMC. The function of the marrow stroma was normal in its ability to support the growth of hematopoietic progenitors from normal marrows seeded onto them in all three cases, but the generation of hematopoietic progenitors from patients marrow cells inoculated onto normal stromas was reduced, thus suggesting the defect to be of stem cell origin. The parents and unaffected brother of one of the families have also been studied in LTBMC and all showed normal hematopoietic and stromal cell function. From this study we speculate that there are some similarities between DC and the defect in the W/Wv mouse.  相似文献   
59.
目的:探讨椎动脉V1段狭窄支架置入术患者的护理方法。方法:选择实行椎动脉V1段狭窄支架置入术患者35例。全部采用经股动脉穿刺插管行全脑血管造影显示有血管狭窄并行椎动脉V1段支架置入术及围手术期护理。结果:均成功置入支架,患者临床症状改善明显,未发生严重并发症。结论:加强手术前后的护理,严密观察病情及预防并发症的发生,患者主动配合治疗是手术成功的关键。  相似文献   
60.
 目的 观察硼替佐米(商品名:万珂,PS-341)对柔红霉素(DNR)诱导的K562耐药细胞株(K562/DNR)核因子-κB(NF-κB)、抑制蛋白κB(IκB)及P-糖蛋白(P-gp)表达的影响,探讨PS-341逆转耐药的分子机制。方法 以100 μg/ml DNR单用或联合应用4 μg/L PS-341分别作用于K562/DNR 12、24及36 h,检测不同时间点各组NF-κB、IκB及P-gp表达情况,同时测定NF-κB p65活性,检测各组细胞凋亡率。结果 Western blot结果显示:与阴性对照组相比,DNR可诱导NF-κB表达上调及活性增强、IκB表达下调、P-gp表达上调;加用PS-341可显著抑制 DNR诱导的NF-κB及P-gp表达,使IκB表达增加。加用PS-341后,NF-κB活性12 h为(15.3±1.87)%[DNR组为(23.8±2.27)%],24 h为(10.2±1.69)%[DNR组为(25.4±1.98)%],36 h为(6.08±2.53)%[DNR组为(26.9±2.58)%],与相应单用DNR组相比均有明显下降,差异有统计学意义(P值均<0.05)。DNR与PS-341联用后,细胞凋亡率12 h为(35.23±5.15)%[DNR组为(15.56±4.12)%],24 h为(40.26±6.89)%[DNR组为(17.25±2.89)%],36 h为(43.58±7.69)%[DNR组为(22.47±4.58)%],与DNR组相比,细胞凋亡率均明显增加,差异具有统计学意义(P值均<0.05)。上述作用呈时间依赖性。结论 PS-341可减少K562/DNR细胞NF-κB的活化,降低P-gp表达,逆转细胞耐药,促进细胞凋亡。  相似文献   
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