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111.
Background: Previous work has demonstrated that ongoing hemorrhagic shock dramatically alters the distribution, clearance, and potency of propofol. Whether volume resuscitation after hemorrhagic shock restores drug behavior to baseline pharmacokinetics and pharmacodynamics remains unclear. This is particularly relevant because patients suffering from hemorrhagic shock are typically resuscitated before surgery. To investigate this, the authors studied the influence of an isobaric bleed followed by crystalloid resuscitation on the pharmacokinetics and pharmacodynamics of propofol in a swine model. The hypothesis was that hemorrhagic shock followed by resuscitation would not significantly alter the pharmacokinetics but would influence the pharmacodynamics of propofol.

Methods: After approval from the Animal Care Committee, 16 swine were randomly assigned to control and shock-resuscitation groups. Swine randomized to the shock-resuscitation group were bled to a mean arterial blood pressure of 40 mm Hg over a 20-min period and held there by further blood removal until 42 ml/kg of blood had been removed. Subsequently, animals were resuscitated with lactated Ringer's solution to maintain a mean arterial blood pressure of 70 mm Hg for 60 min. After resuscitation, propofol (750 [mu]g[middle dot]kg-1[middle dot]min-1) was infused for 10 min. The control group underwent a sham hemorrhage and resuscitation and received propofol at the same dose and approximate time as the shock-resuscitation group. Arterial samples (20 from each animal) were collected at frequent intervals until 180 min after the infusion began and were analyzed to determine drug concentrations. Pharmacokinetic parameters for each group were estimated using a three-compartment model. The electroencephalogram Bispectral Index Scale was used as a measure of drug effect. Pharmacodynamics were characterized using a sigmoid inhibitory maximal effect model.

Results: The raw data demonstrated minimal differences in the mean plasma propofol concentrations between groups. The compartment analysis revealed some subtle differences between groups in the central and slow equilibrating volumes, but the differences were not significant. Hemorrhagic shock followed by resuscitation shifted the concentration effect relationship to the left, demonstrating a 1.5-fold decrease in the effect-site concentration required to achieve 50% of the maximal effect in the Bispectral Index Scale.  相似文献   

112.
目的 :总结乳腺癌的发病规律、早期临床表现 ,提高乳腺癌的诊断及治疗水平。 方法 :对 115例乳腺癌患者的临床表现、诊断、治疗和预后进行回顾性分析。 结果 :红外线诊断占 78 3% (18/ 2 3) ,X线钼靶的诊断占93 5 % (2 9/ 31) ,细胞学诊断占 80 % (16 / 2 0 )。分期早期与晚期的雌激素受体 (ER)及抗凋亡相关基因 (Bag 1)的表达差异无统计学意义 (P >0 .0 5 ) ,腋淋巴结转移组与无淋巴结转移组Bag 1的表达差异有统计学意义 (P <0 .0 5 )。随访 89例 ,2年、5年生存率分别为 92 .1% (82 / 89)和 85 7% (5 4 / 6 3)。 结论 :本组乳腺癌患病年龄以 4 1~6 0岁年龄多见 ,红外线、X线钼靶、细胞学检查是诊断乳腺癌的主要手段。早诊断、早治疗是提高乳腺癌患者生存率的关键。  相似文献   
113.
锁骨下动脉损伤及创伤性假性动脉瘤手术方法探讨   总被引:2,自引:0,他引:2  
目的探讨锁骨下动脉损伤及创伤性动脉瘤的外科治疗方略。方法1991—2005年对2例锁骨下动脉损伤,6例锁骨下假性动脉瘤根据病变的部位、程度及受伤时间、累及范围等选择手术入路,采用血管缝扎、血管壁修补、血管吻合、血管移植、辅助体外循环及球囊止血技术实施手术。结果6例痊愈,1例动静脉狭窄,1例动脉闭塞伴臂丛损伤。平均失血800mL。结论锁骨下动脉损伤及假性动脉瘤手术复杂,术前对病变进行仔细评估,选择合理的切口及手术方法是减少并发症的关键。  相似文献   
114.
Intermediate trophoblast is a distinct form of trophoblast, the presence of which in uterine curettings is considered a reliable indicator of intrauterine pregnancy even in the absence of chorionic villi. However, the appearance of intermediate trophoblastic cells have not been described in sufficiently specific terms to permit their reliable identification, and distinction from decidual cells can be difficult. We have noticed for some time that the intermediate trophoblastic cells often show multiple deep clefts in the nuclei, and the present study was performed to address the issue of whether this nuclear feature is reliable for their identification. We reviewed 242 uterine curettings of intrauterine pregnancy, documented by the presence of chorionic villi, and were able to find a distinct population of cells with large, hyperchromatic, multiclefted nuclei scattered in the decidua in 88% of the cases. In most instances, these cells produced a characteristic variegated pattern that was readily recognizable at low magnification. Positive immunostaining for cytokeratin (CAM 5.2) in these isolated cells within the decidua confirmed their trophoblastic nature. In contrast, multiclefted nuclei were absent in the 51 negative control cases, which included decidualized endocervical polyps (40 cases), uterine curettings from patients with tubal pregnancy (10 cases), and endometriosis with decidual change (one case). We conclude that intermediate trophoblastic cells can usually be reliably identified in curettings of intrauterine pregnancy by their characteristic nuclear multiclefting.  相似文献   
115.
Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients.  相似文献   
116.
The serum apolipoprotein A- I (apo A-I) Concentrations in 39 patients with posthepatitis cirrhosis were reported to be 0.87±0.27 g/L lower than that of controls 1.15±0.14 g/L P<0.01. The, decrease of apo. A-I was correlated with the severityof impaired liver function. Apo A- I concentrations in serum correlated positively with decrease of serum albumin (r=0.503 P< 0.01) and negatively with serum bilirubin increase (r=- 0.508 P <0.01) . The data indicate that decreasing of apo A- I concentration may be regarded as one of the reliable indices reflecting the degree of liver function impairment.  相似文献   
117.
本文报道用550型全自动生化分析仪,以速率法测定尿NAG活性及本室尿NAG活性的正常参考范围;并对可能影响尿NAG活性的尿PH,尿素浓度等进行了干扰试验及分析。  相似文献   
118.
To evaluate the clinical usefulness of gallium 67 imaging in the detection of gastrointestinal (GI) non-Hodgkin's lymphoma (NHL) and in the assessment of the therapeutic effects, images were reviewed in 24 cases (25 lesions: stomach, 20; ileum, 2; and terminal ileum and/or cecum, 3) and were compared using barium studies and, in 16 cases, computerized tomography (CT). In all, 23 (92.0%) of the 25 lesions were detected by67Ga citrate imaging, the barium studies detected all 25, and CT detected 15 of 16 lesions (93.8%). The two lesions not identified by imaging and the one not found by CT were the smallest of all. In 2 (8.7%) of the 23 lesions positively identified by67Ga-citrate imaging, both CT and imaging revealed the extent of the tumor more accurately than did the barium studies. In all but one of the patients, a close correlation existed between the imaging results and the therapeutic effects. These data suggest that67Ga imaging is useful in conjunction with CT and barium studies for the detection of GI NHL and for the assessment of both the spatial extent of disease and the therapeutic effects, although a lack of67Ga uptake after therapy does not always indicate a good therapeutic effect.  相似文献   
119.
本文采用有酸性条件下用乙酸乙酯萃取呋喃妥因后,通过二阶导数光谱法测定尿中呋喃妥因的浓度。该法定量信息为374 ̄377nm处的峰谷之间距离,最低检出浓度为1.5mg/L,回收率为98%,相对标准差小于3%;本法与HPLC法进行了对照性研究。两法具有明显的相关性(r=0.9991)。本法可用于呋喃妥因药动学的研究。  相似文献   
120.
目的:观察中西医结合治疗急性胰腺炎的疗效。方法:西药组23例用西药治疗,中西医结合组19例在用西药治疗的基础上加用柴芍承气汤及丹参注射液治疗。结果:中西医结合组疗效明显优于西药组(P<0.05)。结论:中西医结合治疗急性胰腺炎可明显改善急性期症状,减少并发症,改善预后。  相似文献   
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