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91.
肝癌术后监测血清AFP的临床意义(附70例报告)   总被引:3,自引:0,他引:3  
为探讨肝癌术后监测血清甲胎蛋白(AFP)的临床意义,回顾性分析1996年2月至2002年3月间肝癌根治切除术后定期监测发现血清AFP阳性的70例患者AFP升高与肿瘤残留、复发或转移的关系。肝癌术后血清AFP升高可见于肝癌的残留或早期转移、肝癌的复发或转移、肝癌的再发以及晚期肝硬变4种情况。对肝癌患者术后定期作AFP检查,有助于检出AFP阳性肝癌患者的肿瘤残留及亚临床期复发转移,不仅适用于术前AFP阳性,而且适用于术前AFP阴性的肝癌患者。肝癌患者术后AFP下降,但不能降至正常,可能与晚期肝硬变肝脏内干细胞-卵圆形细胞代偿性增生有关。  相似文献   
92.
长效驱避剂的初步筛选研究   总被引:4,自引:1,他引:3  
目的 研究一种对人有效保护时间 >8h ,且安全经济的长效驱避剂配方。方法 采用实验室 (GB T173 2 2 .10 -1998)和现场的药效测试方法对所配制的驱避剂配方进行效果测试。结果 实验室试验表明 ,以 2 0 %IR3 5 3 5配制 10、12、13、14号驱避剂配方在实验室内对白纹伊蚊的有效防护时间可达 8h以上 ;现场试验表明 ,10、12、13、14号驱避剂配方对人有效防止丘陵地区伊蚊的叮咬时间达 9h ,有效防止稻田地区中华按蚊的叮咬时间达 8h。结论以 2 0 %IR3 5 3 5与纤维素配制的驱避剂对人的有效保护时间可达 8h。纤维素对IR3 5 3 5有一定延长有效保护时间的缓释作用。实验所用配方对人的皮肤无不良反应 ,可作为户外活动人群防止蚊虫刺叮的驱避剂。  相似文献   
93.
The aim of this investigation was to determine whether age-related changes in the dynamics of muscle activation were, in part, responsible for longer reaction times (RT) in the elderly. A group of 12 young (mean age, 20.6 years) and 12 elderly (mean age, 64.3 years) women performed a series of ballistic forearm supination movements in response to an auditory stimulus while using a simple reaction time test. Surface electromyographic waveforms from biceps brachii (agonist) and pronator teres (antagonist) muscles were recorded, together with the angle-time curves representing the motion of the forearm, on to an IBM compatible microcomputer. The results showed that an age-related increase (P<0.05) in motor reaction time (MRT) contributed to longer RT in the elderly. In addition, the longer (P<0.05) MRTs in the elderly were associated with a significantly slower rate (P<0.05) of biceps brachii muscle activation and a significantly increased proportion (P<0.05) of the initial biceps brachii muscle burst required to initiate the movement. This data suggested that an important part of the slowing of motor behaviour, commonly observed with increasing age, may be due to either decreases in the ability of aged skeletal muscle to rapidly generate tension or to a reduction in motor drive.  相似文献   
94.

1. 1. Acute effects of alcohol and diazepam on reaction time (RT) and event-related potential (ERP) measures were examined in 108 healthy male volunteers.

2. 2. The subjects engaged in a simple RT task at two levels of stimulus intensity during baseline and treatment sessions.

3. 3. Lower stimulus intensity produced increased RTs, increased ERP peak latencies, and suppression of peak amplitudes.

4. 4. Moderate and high doses of alcohol, and high doses of diazepam produced increased RTs. Alcohol suppressed P100 and N100 amplitudes, while diazepam suppressed P100 amplitudes only. P100 amplitudes were correlated to RTs under baseline and treatment conditions.

5. 5. These results were taken as evidence for impaired stimulus detection during alcohol and diazepam intoxication, with both drugs influencing sensory-perceptual processes and alcohol alone influencing the degree of attentiveness.

Author Keywords: alcohol; diazepam; event-related potentials; simple reaction time  相似文献   

95.
Optic nerve injury demonstrated by MRI with STIR sequences   总被引:1,自引:0,他引:1  
We studied nine patients with optic nerve injury associated with closed head trauma by magnetic resonance imaging (MRI) with short inversion time inversion recovery (STIR) sequences on 11 occasions from 4 days to 14 years after the injury: three studies were within 17 days and eight over 4 months to 14 years. MRI revealed abnormal high signal in 10 of the 11 injured nerves. MRI 4 days after the injury showed no abnormality.  相似文献   
96.
79只眼底病患眼的光照黄斑部试验(MPT)结果显示:中心性浆液性脉络膜视网膜病变、老年性黄斑变性渗出型和Rieger型中心性渗出性脉络膜视网膜病变患眼的光照黄斑恢复时间显著延长,其它黄斑部病变患眼也有不同程度的延长。本文结合眼底荧光血管造影和黄斑视野域值试验对光照黄斑部试验的机理进行了探讨。  相似文献   
97.
The treatment times for the fabrication of Extensive Amalgam Restorations (EAR) as recorded in a longitudinal clinical trial at the Dental School in Nijmegen were analyzed. 269 EAR's with different retention methods were made on molars by three operators. A mean total treatment time of 60 min was found. The factor operator had a significant influence on all treatment phases resulting in a 26% difference in total treatment time between operators. Also significant influences were found in some treatment phases for the factor retention, side location of the tooth and extension of the restoration. The results of this study with regard to treatment times must be considered from the perspective of the quality of the care provided.  相似文献   
98.
Ten-year stability of cardiovascular responses to laboratory stressors   总被引:1,自引:0,他引:1  
In this study we examined test-retest stability of cardiovascular stress responses over a decade of the life span. Participants were 55 male college undergraduates. 19 years of age at initial testing, and 29 years of age at follow-up testing Stressors were a foot cold pressor and an aversive reaction time task. Cardiovascular measures included systolic and diastolic blood pressure, heart rate, and preejection period. For cold pressor, the magnitude and pattern of cardiovascular responses remained unchanged at the 10-year follow-up. For the reaction time task, the characteristic cardiovascular response patterns was preserved but with significant attenuation of magnitude. The present findings are consistent with previous observations of temporal stability but over a substantially longer test-retest interval. The long-term stability of stress responses is discussed in the context of stress test methodology, behavioral response demands, and maturation of the physiological systems involved in cardiovascular response expression.  相似文献   
99.
两种术式治疗多囊卵巢综合征的远期疗效追踪比较   总被引:1,自引:0,他引:1  
[目的]评价开腹卵巢楔形切除(OWR)和腹腔镜下双侧卵巢电灼开窗术(LOD)两种术式对多囊卵巢综合征(PCOS)的远期疗效.[方法]1981至2001年在我院诊断为PCOS并接受手术治疗的妇女共151例,其中行OWR 61例、LOD 90例,追踪分析两组妇女术后妊娠率、术后妊娠时间的分布及术前后月经模式变化.[结果]两组的临床特征具有可比性,OWR组累积妊娠率84%,LOD组累积妊娠率72%,两组间没有明显差异,绝大部分妊娠发生在术后18个月内;OWR组术后3个月、半年、1年、3年、5年及10年月经规律的妇女所占的比例分别是81.3%、81.3%、77.3%、77.6%、78.9%、85.2%,明显高于术前的31.1%(P值<0.05);LOD组术后3个月、半年、1年、3年、5年及10年月经规律的妇女所占的比例分别是80.6%、63.5%、56.7%、58.0%、57.6%、42.9%,明显高于术前的35.6%(P值<0.05);术后OWR组月经规律妇女占的比例明显高于LOD组(P均<0.05).[结论]两种术式的术后妊娠率相似.OWR比LOD更好、更长远地改善PCOS妇女的月经异常.  相似文献   
100.
A restricted field of view (rFOV) approach for imaging a dynamic time series of volumes of limited spatial extent within a larger subject is described. The shorter readout with rFOV-MRI can be exploited to either limit image artifacts or increase spatial resolution. To accomplish rFOV imaging of a multislice volume for a dynamic series, an outer volume suppression (OVS) preparation that saturates signal external to a cylinder through the subject is followed by slice-selective excitation and a spiral readout. The pass- and stopband efficiencies of the OVS in an agar gel phantom were 97% (+/-1.5%) and 3% (+/-1%), respectively. Profiles of the temporal signal-to-noise ratio (SNR) were measured in a phantom and an adult brain. The rFOV sequence reduced distortions from off-resonance signal and T2*-induced blurring compared to a conventional sequence. Sequence utility is demonstrated for high-resolution rFOV functional MRI (fMRI) in the visual cortex. The rFOV sequence may prove to be useful for other multislice dynamic and high-resolution imaging applications.  相似文献   
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