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101.
目的研究18F-FDGSPECT/CT符合线路正电子显像在鉴别乳腺肿块性质和乳腺癌术前淋巴结转移分期中的应用价值。方法22例有乳腺肿块的女性患者行SPECT/CT符合线路18F-FDG显像,患者禁食6h以上,肘静脉注射18F-FDG185MBq~296MBq。静注60min后开始发射和X线CT透射扫描,然后进行符合线路PET连续采集30min。图像经X线衰减校正和有序子集最大期望值法(COSEM)叠代重建后,得到横断面、冠状面、矢状面三维断层图像及CT与FDGSPECT的融合图像。结果22例患者均通过手术切除治疗并获得病理结果。其中,乳腺癌16例,乳腺良性肿瘤6例。FDGSPECT诊断乳腺癌的敏感度、特异性和准确度分别是93.75%、100%和95.45%,明显高于乳腺X射线摄片。16例乳腺癌患者,15例FDGSPECT分期与临床手术分期一致。利用SPECT/CT仪所配备的定位CT,15例乳腺癌患者的病灶可准确定位。结论SPECT/CT符合线路18F-FDG显像在乳腺癌的诊断、转移灶定位以及临床分期方面具有重要的临床应用价值。  相似文献   
102.
以 400μW/(min·cm~2)剂量紫外线照射减毒日本血吸虫尾蚴, 1 次免疫小鼠(200条/只)可产生抗日本血吸虫感染的免疫能力。这种免疫力至少可维持7个月。1、3、5、7个月各组中,免疫组与攻击组虫荷均数比较,差异均有显著性意义。1、3、5和7个月所获减虫率分别为71.28%、69.63%、62.26%和46.16%,7个月与1、3、5个月比较,差异有显著性意义,提示7个月时小鼠抗日本血吸虫的免疫力可能有所下降。  相似文献   
103.
抑郁症的基础与认知激活脑SPECT显像   总被引:17,自引:6,他引:11  
目的通过抑郁症患者基础和认知激活局部脑血流(rCBF)灌注显像的半定量分析,评估抑郁症患者的脑血流灌注异常。方法选择27例未经抗抑郁治疗、ICD10分类为中度抑郁发作伴躯体症状的患者,15例年龄匹配的健康人作正常对照。27例患者中21例、15例健康人中13例行双日法基础与认知激活脑rCBF显像;另6例患者及2例健康人仅行基础脑SPECT显像。认知激活采用Wisconsin卡片分类试验。半定量分析在横断面图像7~11帧上进行,将各ROI的平均计数与同侧小脑的最高计数相除,得到各ROI的rCBF比值。结果抑郁症左额叶和左颞叶的基础rCBF值均为0720,明显低于对照组(0764和0750,P<005);左额、左颞、左顶叶的认知激活rCBF值分别为0719、0690及0701,明显低于对照组(0782、0752和0766,P<001和P<005)。结论①抑郁症患者存在左额叶、左颞叶的局部血流低灌注。②额叶、颞叶皮层低灌注可能是引起抑郁症认知障碍、心境低落的原因。③Wisconsin卡片分类试验认知激活脑SPECT显像有助于提高抑郁症的诊断准确性  相似文献   
104.
壳聚糖对豚鼠单一心室肌细胞延迟外向钾电流的作用   总被引:3,自引:1,他引:2  
研究壳聚糖对豚鼠单一心室肌细胞延迟外向钾电流(Ik)的作用,从离子通道角度初步春作用机理。应用膜片钳全细胞记录方式,设保持电位为-40mV,指令电位为-60 ̄+70mV,步阶脉冲10mV,刺激频率1Hz,波宽300ms,刺激间隔6s的方波钳制方案。结果表明壳聚糖能抑制Ik,并具有浓度依赖关系,能抑制豚鼠单一心室肌细胞延迟外向K^+电流。  相似文献   
105.
Readings were performed on day (D)2, D3 and D4 after application of patch tests in NN patients. 90 patch lest reactions in 49 patients were interpreted as allergic und of past or present relevance. A single D2 reading detected 58 of the allergic reactions, with 32 false-negatives and 23 false-positives. A single D3 reading detected 77 allergic reactions, with 13 false-negatives and 17 False-positives. A single D4 reading detected 85 allergic reactions, with 5 false-negatives und 4 false-positives. Therefore, if only a single reading is feasible, it is better performed on D4 than on D3.  相似文献   
106.
Pneumatic ventricular assist device (VAD) was utilized for cardiogenic shock after intracardiac operation in two children with complex cardiac anomalies based with single ventricle. In the first case (a 10-year-old), after a modified Fontan operation, VAD was placed between the functional left atrium and ascending aorta, serving as a "artificial single ventricle" with neither pumping chamber nor artificial support in the right side of the heart. The systemic circulation was maintained by keeping relatively high central venous pressure. In another child (a 3-year-old) who underwent repair of incompetent atrioventricular valve leaving intracardiac lesions, VAD was placed between the common atrium and ascending aorta, serving as a pump for both pulmonary and systemic circulation with regulation of pulmonary blood flow through an aortopulmonary Gore-Tex shunt. The circulatory assist with VAD was utilized for 5 and 6 days, respectively. Although weaning from the device was not feasible in both patients because of the pulmonary dysfunction, these experience showed the possible use of VAD for cardiogenic shock after surgery in patients with complex cardiac anomalies.  相似文献   
107.
Summary Fourty-two consecutive patients with craniopharyngioma were treated by stereotactic approach, i.e. preferentially stereotactic puncture and installation of colloid isotope into cystic tumours and external stereotactic single dose irradiation to solid tumour parts. In a minority of cases, such treatment was less suitable, and surgical removal and/or radiotherapy was used. There was no peroperative mortality. A long-term follow up (observation time 10–23 years) of the 31 patients alive indicated that they were socially well adapted with a high rate of fulltime work and a low rate of intercurrent disease. In spite of substitution therapy for pituitary insufficiency in most cases, the patients were subjectively seldom disturbed by their disease.Our results support a change in the choice of therapy for craniopharyngioma patients, from open neurosurgery to the less invasive stereotactic techniques.  相似文献   
108.
Summary The clinical tolerance and pharmacokinetics of FCE 22101 (sodium (5R, 6S)-6-[(1R)-hydroxyethyl]-2-carbamoyloxymethyl-2-penem-3-carboxylate), a new penem antibiotic, have been studied after giving a single i.v. dose of 4 mg·kg–1 to ten healthy male volunteers. The pharmacokinetics was estimated according to a two-compartment open model. The peak plasma concentration (Cmax) was 15.5 (1.08) µg·ml–1, mean (SEM). FCE 22101 was rapidly cleared from the systemic circulation [ =44.2 (4.2) min; CL=7.21 (0.47) ml·kg–1·min–1]. The mean apparent volume of distribution at steady-state was 246 (16.9) ml·kg–1. The mean residence time relative to the 10 min infusion was 39.4 (1.5)min. Urinary recovery of FCE 22101 showed wide inter-subject variation, ranging from 10.2 to 53.6% of the dose. No subject complained of adverse effects.  相似文献   
109.
为探讨单链抗体 (ScFv )对重症肌无力 (MG )的特异性免疫治疗作用 ,从分离自MG患者胸腺的抗乙酰胆碱受体(AchR )抗原结合片段Fab6 37构建单链抗体ScFv6 37。应用放射免疫测定法测定了ScFv6 37与刺激抗原人AchR的特异性结合活性以及与相关抗原大鼠AchR和电鳐AchR的交叉反应 ,应用竞争性ELISA测定抑制致病性抗AchR完整抗体IgG6 37与人AchR结合活性。结果发现ScFv6 37只能与人AchR结合 ,不能与大鼠和电鳐的AchR结合。对IgG6 37与人AchR结合的抑制率为 17 5 %~ 32 9%。表明单链抗体对AchR具有一定的“保护”作用。  相似文献   
110.
BACKGROUND: Single embryo transfer (particularly of a top quality embryo) is an excellent model to correlate embryo quality in terms of morphological criteria to early pregnancy. We investigated whether this model could provide us with more information on what happens after implantation in the first trimester of pregnancy. METHODS: The outcome of 370 consecutive single top quality embryo transfers in patients younger than 38 years was analysed for pregnancy and first-trimester pregnancy loss (FTPL) before 13 weeks of gestation. Analysis was done on each cohort of embryos from which the transferred top quality embryo was selected. Serum HCG levels were measured on day 8 and day 12 after day 3 embryo transfer. The HCG index was calculated as the level of HCG on day 12/HCG on day 8. RESULTS: The pregnancy rate after single top quality embryo transfer was 51.9%. This was independent of the patients' age. FTPL, however, appeared to be age dependent: 15.4% for the whole group, 9% in patients younger than 30 years and 19% in patients above 30 years. The pregnancy rate was 50% in IVF cycles and 52% in ICSI cycles; FTPL was 19% in IVF cycles and 10% in ICSI cycles. Multiple regression analysis showed that these differences originated from age differences between both populations rather than from technique-related factors. An HCG level >or=45 IU/l on day 12 was predictive for ongoing pregnancy with 75.6% sensitivity and 100% specificity; an HCG index >or=3.5 similarly predicted ongoing pregnancy with 72.3% sensitivity and 100% specificity. CONCLUSIONS: These data show that embryo selection for transfer on day 3 can be used as an excellent tool for prediction of pregnancy but not for prediction of FTPL. The pregnancy rate of a single top quality embryo is not related to age, whereas FTPL is age dependent.  相似文献   
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