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31.
Direct effects of endotoxin on hepatocytes. Synthesis of a specific secretory protein 总被引:2,自引:0,他引:2
J E Mazuski J L Platt M A West R L Simmons H C Towle F B Cerra 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(3):340-344
The synthesis of acute-phase proteins by the liver during sepsis has been thought to be induced primarily by monokines released from activated macrophages, although glucocorticoid hormones may also stimulate this process to a lesser degree. According to this concept, synthesis of these proteins following administration of bacterial endotoxins would be an indirect effect and would not reflect a direct interaction of the endotoxin molecule with the hepatic parenchymal cell. We observed, however, that the synthesis of a 23-kilodalton protein was stimulated directly by the addition of lipopolysaccharide to cultures of primary mouse hepatocytes. The synthesis of this protein was also stimulated by glucocorticoids and interleukin 1. These findings demonstrate that certain hepatic proteins are subject to complex regulation by several factors thought to be important mediators of sepsis; in addition, they suggest that hepatic parenchymal cells may have the intrinsic capacity to respond directly to bacterial endotoxins. 相似文献
32.
D W Vane J Pritchard C W Colville K W West H Eigen J L Grosfeld 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(7):885-888
One hundred thirty-one children underwent rigid bronchoscopy under general anesthesia for suspected aspirated foreign bodies. There were 79 boys and 52 girls, with a mean age of 2.1 years. Physical examination showed decreased breath sounds (n = 130) and wheezing (n = 119) over the affected site. Chest roentgenograms were diagnostic or suggestive of aspirated foreign bodies in 127 cases (97%). Radiopaque lesions were noted on roentgenograms in ten cases. Four infants had a preoperative hypoxic arrest. Two patients had negative results of bronchoscopy (1.5%). Extraction of the aspirated foreign body was carried out at laryngoscopy in two patients and by forceps under direct vision at bronchoscopy in 97 patients. A Fogarty catheter was used in 12 cases. Postendoscopic complications included fever (n = 27), pulmonary infiltrate (n = 11), ventilatory support (n = 4), and pneumothorax (n = 2). Rigid bronchoscopy for aspirated foreign body in children is a safe, effective, and sometimes life-saving procedure. Morbidity is low and mortality is zero. 相似文献
33.
R D Curran T R Billiar M A West B G Bentz R L Simmons 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(11):1373-1378
Interleukin 2 (IL-2) is an essential mediator of the immune response and has also been shown to be protective in experimental models of sepsis. Macrophages have IL-2 receptors but their function is unknown. We investigated the effect of IL-2 on Kupffer cells, the fixed macrophages of the liver, using an in vitro rat hepatocyte-Kupffer cell coculture system. In this model, endotoxin (lipopolysaccharide) triggers Kupffer cells to induce suppression of hepatocyte protein synthesis. We found that pretreatment with 10 U/mL or more of IL-2 primed Kupffer cells, significantly reducing the concentration of lipopolysaccharide necessary to trigger Kupffer cell-mediated suppression of hepatocyte protein synthesis. Higher concentrations of IL-2 (greater than or equal to 1 x 10(4) U/mL) alone were capable of priming and triggering Kupffer cells to suppress hepatocyte protein synthesis. These data show that IL-2 increases Kupffer cell sensitivity to endotoxin, suggesting that IL-2 may play an important role in regulating macrophage responses to septic stimuli. 相似文献
34.
Jane Maienschein James L. W. West Betty Bright 《Pediatric nephrology (Berlin, Germany)》2004,19(12):1437-1438
35.
36.
目的 探讨Y染色体无精症因子C区(azoospermia factor C,AZFe)无精症缺失基因(deleted-in-azoospermia,DAZ)家族基因拷贝缺失与中国男性原发不育之间的关系。方法 运用多重PCR与PCR-RFLP检测技术,对210例已生育男性、216例原发无精症与189例严重少精症患者Y染色体AzFc区域DAZ基因家族的基因拷贝数进行分析。结果 在所有已生育男性中未检出DAZ基因拷贝的完全或部分缺失,而在原发无精症与严重少精症患者中DAZ基因拷贝完全缺失率分别为8.8%和12.2%,DAZ1/DAZ2共缺失率分别为8.3%和5.3%。结论 在中国男性原发无精症与严重少精症患者中存在较高频率的DAZ基因拷贝缺失现象,提示Y染色体AZFc区域DAZ基因家族基因拷贝的完全与部分缺失是中国男性原发不育的遗传高风险因子。 相似文献
37.
Spatial learning in rodents requires normal functioning of hippocampal and cortical structures. Recent data suggest that the cerebellum may also be essential. Neurological mutant mice with dysgenesis of the cerebellum provide useful models to examine the effects of abnormal cerebellar function. Mice with one such mutation, Purkinje cell degeneration (pcd), in which Purkinje cells degenerate between the third and fourth postnatal weeks, were evaluated for performance of spatial navigation learning and visual guidance learning in the Morris maze swim-escape task. Unaffected littermates and C57BL/6J mice served as controls. Separate groups of pcd and control mice were tested at 30, 50 and 110 days of age. At all ages, pcd mice had severe deficits in distal-cue (spatial) navigation, failing to decrease path lengths over training and failing to express appropriate spatial biases on probe trials. On the proximal-cue (visual guidance) task, whenever performance differences between groups did occur, they were limited to the initial trials. The ability of the pcd mice to perform the proximal-cue but not the distal-cue task indicates that the massive spatial navigation deficit was not due simply to motor dysfunction. Histological evaluations confirmed that the pcd mutation resulted in Purkinje cell loss without significant depletion of cells in the hippocampal formation. These data provide further evidence that the cerebellum is vital for the expression of behavior directed by spatial cognitive processes. 相似文献
38.
R K Lamb S A Qureshi J L Wilkinson R Arnold C R West D I Hamilton 《The Journal of thoracic and cardiovascular surgery》1988,96(3):368-375
Between 1968 and 1985, 80 children underwent correction of total anomalous pulmonary venous drainage. There were 47 boys and 33 girls whose ages ranged from 3 days to 16 years (median 2 months, interquartile range 5 years). Seventy (87.5%) were less than 1 year of age at operation. Fifty-eight (72.5%) weighed less than 5 kg, the range being 1.6 to 42 kg (median 3.7 kg, interquartile range 2.4 kg). Forty-five (56%) patients had supracardiac, 14 (17.5%) cardiac, 15 (19%) infracardiac, and 6 (7.5%) had mixed total anomalous pulmonary venous drainage. Follow-up was complete in 78 (97.5%) and ranged from 6 to 189 months (median 58 months, interquartile range 59 months). There were 14 (17.5%) early and six (7.5%) late deaths. Analysis by various factors revealed year of operation as the only factor to affect survival at the 5% level of significance. Early mortality was 29% between 1968-1977 and 11% between 1978-1985 (p = 0.04). Postoperative pulmonary venous obstruction occurred in five (6%) patients between 6 weeks and 3 months after operation. All 5 died, three after reoperation. Five (6%) other children had reoperations, four for residual shunts and one for superior vena caval obstruction. 相似文献
39.
Nimodipine treatment in poor-grade aneurysm patients. Results of a multicenter double-blind placebo-controlled trial 总被引:4,自引:0,他引:4
K C Petruk M West G Mohr B K Weir B G Benoit F Gentili L B Disney M I Khan M Grace R O Holness 《Journal of neurosurgery》1988,68(4):505-517
A multicenter, randomized placebo-controlled double-blind trial of nimodipine in poor-grade aneurysm patients was carried out in 17 Canadian hospitals. Of 188 patients enrolled in the trial, 32 were excluded for protocol violations and two were excluded due to statistical considerations, leaving 154 patients for valid outcome analysis. Nimodipine treatment was associated with a significantly better outcome (p less than 0.001): 21 (29.2%) of 72 nimodipine-treated patients had a good outcome at 3 months after subarachnoid hemorrhage (SAH) compared to eight (9.8%) of 82 placebo-treated patients. Delayed ischemic deficits from vasospasm alone were significantly less frequent in the nimodipine group (p less than 0.05) with permanent deficits occurring in five nimodipine-treated patients (6.9%) and in 22 placebo-treated patients (26.8%). Improvement in the good outcome rate and reduction in delayed ischemic deficits from vasospasm alone occurred in both Grade 3 and 4 patients, with no difference between nimodipine- and placebo-treated patients being found in Grade 5 patients. Repeat angiography after Day 4 was carried out in 124 patients. There was no significant difference in the incidence of moderate or severe diffuse spasm, which was seen in 64.3% of nimodipine-treated patients and 66.2% of placebo-treated patients. The authors conclude that nimodipine treatment in poor-grade patients with SAH results in an increase in the number of good outcomes and a reduction in the incidence of delayed neurological deterioration due to vasospasm. This effect occurs by a mechanism other than prevention of large-vessel spasm as visualized on angiography. 相似文献
40.
变形链球菌表面蛋白和葡糖基转移酶基因疫苗对唾液变形链球菌和牙菌斑的影响 总被引:2,自引:0,他引:2
目的 了解变形链球菌表面蛋白和葡糖基转移酶基因疫苗单独及联合免疫对定菌鼠唾液变链菌和牙面菌斑的影响。方法 2 8d龄 Wistar大鼠 3 6只 ,随机分为 pc DNA3 - pac组、pc DNA3 - gtf B组、pc DNA3 - pac联合pc DNA 3 - gtf B组、变形链球菌灭活全菌组、pc DNA3空载体组和 PBS液组 ,进行三次双侧颌下腺腺周注射免疫 ,建立定菌鼠模型 ,作诱龋实验 3个月。唾液变链菌计数和菌斑计分。结果 唾液变链菌菌落计数和牙面菌斑计分在 pc D-NA3与 PBS组最高 ,其次为单基因疫苗免疫组 ,联合基因疫苗和灭活全菌细胞免疫组最低 ,各组间有显著性差异 ( P<0 .0 5 )。结论 pc DNA3 - gtf B和 pc DNA3 - pac具有明显的免疫抑菌作用 ,联合基因疫苗免疫优于单基因疫苗 相似文献