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71.
: A rising prostate specific antigen (PSA) following treatment for adenocarcinoma of the prostate indicates eventual clinical failure, but the rate of rise can be quite different from patient to patient, as can the pattern of clinical failure. We sought to determine whether the rate of PSA rise could differentiate future local versus metastatistic failure.

: Two thousand six hundred sixty-seven PSA values from 400 patients treated with radiotherapy for localized adenocarcinoma of the prostate were analyzed with respect to PSA patterns and clinical outcome. Patients had received no hormonal therapy or prostate surgey and had ?4 PSA values post-treatment PSA rate of rise, determined by the slope of the natural log, was classified as gradual (< 0.69 log (ng/ml)/year, or doubling time (DT) > 1 year), moderate (0.69-1.4 log (ng/ml)/year, or DT 6 months-1 year), or rapid [>1.4 log (ng/ml)/year, or DT < 6 months].

: SIxty-one percent of patients had non-rising PSA following treatment; 25% of patients with rising PSA developed clinical failure, and 93% of patients with clinical failure had rising PSA. The rate of rise discerned different clinical failure patterns. Local failure occurred in 23% of patients with moderate rate of rise versus 7% with gradual rise (p = 0.0001). Metastatic disease developed in 46% of those with rapid versus 8% with moderate rise (p < 0.0001). By multivariate analysis, in addition to rate of rise, PSA nadir and rate of decline predicted local failure; those with post-treatment nadir of 1–4 ng/ml were five times more likely to experience local failure than nadir < 1 ng/ml (p = 0.0002). Rapid rate of rise was the most significant independent predictor of metastastic failure.

: The rate of PSA rise following definitive radiotherapy can predict clinical failure patterns, with a rapidly rising PSA indicating metastatic recurrence and moderately rising PSA local recurrence. This information could potentially dirent therapy; if the rise predicts metastatic failure hormonal therapy could be cosidereed, while aggressive salvage therapy may benefit subclinical local recurrence identified by a moderate rate of PSA rise.  相似文献   

72.
Scintigraphic visualization of intrathecal liposome biodistribution   总被引:1,自引:0,他引:1  
Background: Liposomes containing local anaesthetics have been administered intrathecally and in the epidural space. Poor attention has been given to the pharmacokinetics of liposomes as drug carriers. Therefore, we observed the biodistribution of liposomes after intrathecal injection in rats by scintigraphic imaging during 24 h.
Methods: We administered 99Tc-labeled multilamellar (MLV) and small unilamellar vesicles (SUV) of defined size and volume dispersities into the cerebrospinal fluid at the lumbar level. Those vesicles were free of contamination by radiolabeled colloids as visualized by light and electron microscopy and of neurotoxic products from phosphatidylcholine hydrolysis and peroxidation, both during the preparation process and after 24 h incubation in cerebrospinal fluid at 37°C in vitro.
Results: SUV immediately diffused from the lumbar site of injection to the head and were cleared between 1 and 24 h after injection. MLV were cleared more slowly from the spinal space and appeared in the head region 1 h after injection where they accumulated up to 24 h. These differences were explained in terms of vesicle sizes and volumes. SUV with 0.05 μm diameters were rapidly absorbed into the blood through the arachnoid granulations. In contrast, particles larger than the upper size limit of the arachnoid granulations permeability (±8 μm) could accumulate in the head with a slow elimination rate.
Conclusion: This difference in clearance from the intrathecal space outlines the importance of defining the size of the liposomes, the distribution of a tracer or a drug inside the liposomal preparation, the chemical stability and the absence of toxic degradation products of liposome formulations before clinical use.  相似文献   
73.
使用低流量循环密闭回路内注入给药法,比较1MAC代氟醚和安氟醚各14例维持全麻时循环动力苏醒情况和不良反应。结果;代氟醚在维持阶段对心血管系统的抑制较安氟醚为轻,很可能和代氟醚能使交感神经兴奋性增加有关。  相似文献   
74.
我们对50例子宫、卵巢手术病人,使用利多卡因做硬膜外麻醉,其中25例向硬膜外腔内注入异氟醚-氧化亚氮气体。2组对比发现,实验组麻醉平面明显高于对照组,在同样手术时间内实验组所使用的利多卡因量明显少于对照组。表明异氟醚-氧化亚氮气体有增强利多卡因的硬膜外麻醉作用,同时未发现注入吸入麻醉药产生副作用。  相似文献   
75.
Cerebral blood flow and glucose utilization were measured in rat neocortex, hippocampus and striatum following methylenedioxymethamphetamine injection (5 mg/kg, i.v.), using the tracers [14C]iodoantipyrine and [14C]2-deoxyglucose, respectively. In control rats, blood flow was coupled to glucose metabolism, but in methylenedioxymethamphetamine-treated rats, marked hyperperfusion was measured in frontal and parietal cortex with no change in glucose use. This suggests that methylenedioxymethamphetamine has the potential to disrupt cerebrovascular control.  相似文献   
76.
四肢带表浅静脉干的局部皮瓣在创伤修复中的应用   总被引:1,自引:0,他引:1  
设计4种带表浅静脉干的局部皮瓣用于修复四肢创面14例,获得了满意的效果。该皮瓣所包含的一条浅静脉干,不仅有利于静脉回流,且其血流对皮瓣亦有营养作用。因此,该皮瓣容易成活,长宽比值可大于传统任意型皮瓣。并具有操作简便,不损伤主要动脉等优点。文中介绍了皮瓣的设计及手术方法,并对该皮瓣的血液循环特点、适应证及供区选择等进行了讨论。  相似文献   
77.
40例乳腺癌根治术患者,美国麻醉医师协会(ASA)分级Ⅰ-Ⅱ级,随机分为2且,第1组硬膜外阻滞+臂丛神经阻滞,应用1.33%盐酸利多卡因+0.15%盐酸地卡因+1:20万肾上腺素,硬膜外阻滞首量12ml,臂丛神经阻滞20ml;第2组硬膜外阻滞,应用1.73%碳酸利多卡因+1:20万肾上腺素,首量15ml。两组硬膜外阻滞选为T4-5间隙穿刺。首量给完后测定麻醉药效,并监测患者心率(HR)、平均动脉压(MAP)、血氧饱和度(SpO2),在麻醉前、后30、60、120min抽取动脉血作血气分析。结果显示:第2组麻醉的起效时间、阻滞完善时间要比第1组短(P<0.01)。感觉神经阻滞分段数要比第1组多(P<0.01);两组病人的HR和MAP,麻醉手术中改变不明显。麻醉后面罩给氧。两组病人的SpO2、PaO2增加,PaCO2有所下降,两组比较无统计学意义,但组内前后对照有显著差异(P<0.05)。结果提示碳酸利多卡因硬膜外麻醉下施行乳腺癌根治术具有良好的麻醉效果和更高的安全性。  相似文献   
78.
目的:观察不同麻醉方法对胃癌手术患者红细胞醛糖还原酶(AR)活性及血浆一氧化氮(NO)浓度的影响。方法:28例胃癌手术患者随机分为两组,组1吸入1.5~2.0最小肺泡吸入有效浓度(MAC)的异氟醚,组2为0.5~1.0MAC异氟醚复合硬膜外麻醉。分别于麻醉前30min、手术90min、术后60min、术后1天和术后2天5个时间点抽取静脉血,测定血糖浓度、红细胞AR活性及血浆NO浓度。结果:与麻醉前值相比,组1病人血糖浓度于手术90min、术后60min、术后1天明显升高(P<0.05或P<0.01);术后1天红细胞AR活性明显升高(P<0.05),同时血浆NO浓度显著下降(P<0.05)。组2病人血糖浓度于手术90min、术后60min显著升高(P<0.01);红细胞AR活性及血浆NO浓度,虽有与组1病人相似的变化趋势,但与麻醉前值相比,各时间点无明显变化。术后1天组1病人红细胞AR活性明显高于组2(P<0.05),而血浆NO浓度则相反(P<0.05),两组间血糖无明显差异。结论:胃癌手术病人在应激高血糖状态下,红细胞多元醇途径被激活的同时血浆NO合成受抑制。全麻联合硬膜外阻滞能较好抑制这一改变。  相似文献   
79.
目的 探讨局麻下深龋充填对成人牙科畏惧症的影响。方法 采用Corah’s牙科畏惧症评分法 ,筛选出 10 0例需深龋充填的DF成人患者 ,分为实验组与对照组。实验组在局麻下行深龋充填术 ,对照组则为常规的牙科治疗。结果 实验组DF程度明显降低 ,与治疗前以及对照组比较都有显著性差异 (P <0 .0 1)。牙科治疗过程中两组脉搏的变化有显著性差异 (P <0 .0 1)。结论 局麻下行深龋充填术 ,对成人牙科畏惧症有治疗作用  相似文献   
80.
The objectives of this study were to consider the effectiveness of local anaesthesia (LA) for office-based vitreoretinal (VR) surgery, the requirement to supplement the anaesthetic blockade, the demographic pattern of the sample and the acceptance of LA by patients. This prospective observational audit involved 111 patients that had undergone 128 VR procedures. Assessment data included: patient’s information, details of type of anaesthetic, and pain during surgery. A clinical audit was also carried out with telephone survey to establish the postoperative use of analgesics, the frequency of nausea, emesis, and insomnia. Results suggest that VR surgery can be carried out effectively and safely with LA, in an office-based surgery, provided that experienced surgeons exist. We noted a high degree of patient acceptance, a reasonable level of postoperative pain and a low frequency of nausea and vomits.  相似文献   
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