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61.
62.
We developed a continuous oxygen consumption (Vo2) measurement system employed the reversed Fick method, in which Vo2 in computed from continuously measured sured arterial and mixed venous oxygen saturation assed by pulse oximetry and mixed venous oximetry, respectively, and cardiac output by the heat deprivation technique. This system was compared with the conventional intermittent reversed fick method in 7 patients during surgery and with indirect calorimetry in 4 intensive care unit (ICU) patients. The Vo2 measured by the continuous reversed Fick method showed a high correlation with those simultaneously measured by the intermittent Fick method (r=0.97,P<0.01) and by indirect calorimetry (r=0.74,P<0.01). The 95% confidence limits (bias±2 SD) of the continuous reversed Fick method were −0.6±45 ml·min−1 with the intermittent Fick method and −31±56 ml·min−1 with indirect calorimetry. The continuous Fick method is in satisfactory agreement with the conventional methods for the measured of Vo2 and potentially allows for convenient assessment of Vo2 in critically ill patients. This study was supported in part by Grants-in-Aid for the Encouragement of Young Scientists 01771185 and 04857171 from the Ministry of Education, Science and Culture of Japan  相似文献   
63.
目的:研究犬全脑缺血再灌时浅低温对热休克蛋白70(HSP70)表达的影响,探讨热休克蛋白在低温脑复苏中的作用。方法:采用犬心脏停跳再复苏模型。14只犬随机分成三组:非缺血对照组(n=4)、常规治疗组(n=5)和浅低温组(n=5)。用免疫组化测定脑组织内HSP70表达阳性细胞数密度和反应产物灰度值。结果:犬全脑缺血再灌后HSP70表达明显增强(P<0.01)。浅低温组HSP70表达增强比常规治疗组更明显(P<0.01)。病理损伤明显减轻。结论:浅低温能增加再灌脑组织HSP70表达,并可能是低温脑复苏机制之一。  相似文献   
64.
目的 :评价重症急性胰腺炎 (SAP)早期手术的治疗效果。方法 :回顾性分析 14 7例重症急性胰腺炎 (SAP)的治疗情况 ,其中 38例伴有单个或多个重要脏器功能障碍 (SAP -Ⅱ )。将早期手术治疗的SAP -Ⅱ 2 3例与早期非手术治疗的SAP -Ⅱ 15例在病死率及并发症发生率等方面进行对比分析。结果 :早期手术组中病死率和并发症发生率分别为 30 .4 3% (7/ 2 3)和 34.78% (8/ 2 3) ,早期非手术组中病死率和并发症发生率分别为 6 6 .6 7% (10 / 15 )和 4 6 .6 7% (7/ 15 ) ,两组比较早期手术组的病死率明显低于早期非手术组 (P <0 .0 5 ) ,而并发症发生率差别不大。结论 :早期手术对一些严重的重症急性胰腺炎 (SAP -Ⅱ )患者是必需的。在SAP早期保守治疗期间出现 1个或多个重要脏器功能障碍时应进行手术治疗以降低病死率。  相似文献   
65.
An experimental model for canine visceral leishmaniasis   总被引:6,自引:1,他引:5  
Seven mixed-breed dogs were challenged with either promastigotes or amastigotes of Leishmania donovani infantum strains recently isolated from naturally infected dogs. Different routes and numbers of parasites were utilized and each dog was monitored for at least 1 year post-infection. Anti-parasite specific antibody levels were measured by enzyme-linked immunosorbence, immunofluorescence, crossed-immune electrophoresis and Western blotting on crude antigen. Western blotting on two pure parasite proteins, dp72 and gp70-2, was also done. Mitogenic and antigen-specific stimulation of peripheral blood lymphocytes was monitored; and the haematological, clinical and parasitological parameters measured. Dogs challenged with amastigotes exhibited a more pronounced humoral response to leishmanial antigens. Only in one case was strong antigen-specific proliferation detected. Clinical signs of disease, including hypergammaglobulinaemia, enlarged lymph nodes and the presence of parasites, were also more apparent in the dogs challenged with amastigotes. None of the seven dogs died. Serum antibodies to leishmanial antigens were apparent between 1.5 to 3 months following challenge and correlated with the appearance of enlarged lymph nodes, hypergammaglobulinaemia and the presence of parasites in tissue biopsies. Serum antibodies remained chronically high in these dogs throughout the period of the study. Only one dog (1/3) challenged intravenously with promastigotes and the dog challenged intradermally with amastigotes produced transient antibody responses to leishmanial antigen.  相似文献   
66.
目的 探讨肝脏移植后的免疫损伤与几种主要分子伴侣(热休克蛋白)表达状况之间的内在规律。方法 34份移植后肝脏穿刺标本和10份正常肝脏标本,分为A(无排斥反应)组、B(轻/中度急性排斥反应)组、C(重度急性排斥反应)组、D(慢性排斥反应/肝纤维化)组、E(对照)组。进行HSP60、HSP70、HSP90、HO—1等四种分子伴侣免疫组织化学分析和图像分析。结果 B和C组各指标间无统计学差异,A、D、E与B、C组间有统计学差异。HSP60在移植肝脏中表达降低,排斥反应发生时高;HSP70和HSP90在移植肝脏中升高。HO—1肝脏移植后升高。结论 不同种类的热休克蛋白依据自身表达的特点对移植后的免疫损伤作出反应,体现了细胞的自我保护机制。  相似文献   
67.
The influence of experimentally induced hepatic dysfunction on the pharmacokinetics of Cyclosporine A (CsA) was determined in dogs. The pharmacokinetics of oral (PO) and intravenous (IV) CsA were studied before and after 70 per cent hepatectomy or complete bile duct ligation (CBDL). Changes in liver function were monitored by serial measurements of serum bilirubin, and by the maximum removal rate (Rmax) and plasma disappearance rate (ICG-K) of indocyanine green (ICG). Concentrations of CsA in whole blood were measured by HPLC. Seventy per cent hepatectomy caused significant liver dysfunction: the ICG-Rmax decreased by 47.7±7.1 per cent (mean±SD) and the ICG-K decreased by 61.3±9.7 per cent during the first week after hepatectomy. At the same time, the systemic clearance (CLs) of IV-CsA decreased by 43.9±8.2 per cent, the area under the concentration curve (AUC) of IV-CsA increased by 35.4±20.8 per cent and the bioavailability of CsA decreased by 26.4±14.8 per cent. CBDL also induced significant liver dysfunction: the ICG-Rmax decreased by 39.1±12.8 per cent and the ICG-K decreased by 65.6±3.6 per cent in the second week after the operation. During the same period, the AUC of PO-CsA decreased by 69.9±10.7 per cent and the bioavailability of CsA also decreased markedly by 73.9±15.6 per cent. These data indicate that hepatic impairment significantly influences the pharmacokinetics of CsA, not only by the changes in intestinal absorption, but also by those in hepatic, metabolism. Dose adjustment is therefore necessary in the presence of hepatic dysfunction in order to maintain an adequate blood concentration of CsA without causing side effects. This research was performed in the Department of Surgery, University of Pittsburgh Health Center, University of Pittsburgh, USA  相似文献   
68.
The modulation of drug metabolising enzymes by Masheri extract (ME) and Benzo(a)Pyrene [B(a)P] was studied in male Sprague Dawley rats fed different dietary protein levels. Two groups of 21 days old male Sprague Dawley rats were put on a high protein diet (SHP) with 20% Casein, and a low protein diet (SLP) with 3% Casein semisynthetic based diets for 12 weeks. The SLP fed animals showed lower basal levels of the Phase I activating enzymes viz. Cytochrome P450, Benzo(a)Pyrene hydroxylase, Benzphetamine demethylase and Phase II glutathione detoxification system viz. Glutathione (GSH) and Glutathione-S-transferase. ME and B(a)P treatment significantly depleted the glutathione detoxification system in the SLP group whereas an opposite effect was observed in the SHP group. Interstingly, ME and B(a)P treated rats in the SLP group showed a higher percent increase in the hepatic and pulmonary Phase I enzyme activities than those observed in the treated ME/B(a)P treated SHP rats. Furthermore, both ME and B(a)P significantly decreased the hepatic pool of vitamin A while a concomittant increase in that of vitamin C was observed.  相似文献   
69.
目的:探讨沙漠热环境负重行军血淋巴细胞HSP70的变化规律。方法:对沙漠干热环境中以不同速度和时间负重行军的54名战士和14名对照血淋巴细胞HSP70进行对比分析。结果:相同行军时间的不同行军速度间淋巴细胞HSP70有显性差异(P<0.05);3.5km/h行军3h组淋巴细胞HSP70明显高于对照和行军2h组(P<0.05):5.0km/h行军1.2h组血淋巴细胞HSP70明显高于对照和行军3h组(P<0.05)。结论:随行军速度和时间的增加,淋巴细胞HSP70增高;当行军速度和时间达到一定水平后,机体淋巴细胞HSP70明显增加。血淋巴细胞HSP70作为热损伤和热耐受的监测指标较血浆HSP70敏感。  相似文献   
70.
目的 :研究小肠间质瘤 (smallbowelstromaltumors,SBST)Ki6 7和p5 3免疫组织化学的表达 ,探讨两者在肿瘤良恶性划分和预后中的作用。方法 :选用CD117阳性的SBST 33例进行光镜观察 ,用EnVisionTM+二步法免疫组化方法检测Ki6 7和 p5 3蛋白在肿瘤中的表达情况并与形态学进行比较。 结果 :33例SBST患者 ,男 2 0例 ,女13例 ,年龄 2 1~ 71岁 ,发生于十二指肠 5例 ,空肠 2 2例 ,回肠 6例。肿瘤最大径的范围在 1.5~ 2 0cm之间。在光镜下出现肿瘤内坏死的有 11例。肿瘤核分裂象计数每 5 0个高倍镜视野 0个有 6例 ,1~ 2个 5例 ,≥ 3个的有 2 2例。 33例中良性 4例 ,交界性 4例 ,恶性 2 5例。随访时间为 3~ 180个月 (平均 73.3个月 ) ,结果为良性组 4例均无瘤生存 ;交界性组 2例无瘤生存 ,1例失访 ,1例在无瘤生存 18个月后失访 ;恶性组无瘤生存有 7例 ,带瘤生存者及死亡有 16例 ,2例失访。Ki6 7染色阴性 2例 ,均为良性 ;其余 31例阳性中 ,增殖指数 (阳性细胞数 )大于 5 %的有恶性 16例 (94 .1% ) ,交界性 1例。在免疫组化p5 3染色中 ,恶性组 2 5例均呈阳性表达 (平均阳性细胞数 4 2 .9% ) ,其中 12例阳性细胞数大于 5 0 %。当Ki6 7和 p5 3均为阴性或两者阳性细胞数分别是 <1%和 <10 %时 ,肿瘤呈良性经过 ,预后  相似文献   
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