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21.
Extracellular phospholipase A2 (PLA2) is a proinflammatory enzyme found especially in the inflammatory exudate to modulate blood flow to areas of antigen stimulation. In this study we found that PLA2 exerted a biphasic effect on the proliferation of phytohemagglutinin (PHA)-stimulated human mononuclear cells (PHA MNC). At low concentrations range from 0.001 to 1 U/ml, PLA2 enhanced the proliferation of PHA MNC (maximal increase was 37.0 +/- 5.67%). Conversely, at concentrations over 10 U/ml, PLA2 markedly suppressed the PHA-induced MNC proliferation (maximal decrease was 88.86 +/- 2.89%). PLA2 was non-toxic to lymphocytes after three days culture, unless the concentration was higher than 100 U/ml. The membrane polarization of PHA-stimulated lymphocytes was also increased by PLA2 at a low concentration. In addition, PLA2 displayed a similar effect on the proliferation of streptokinase-streptodornase (SK/SD) or allogeneic cell stimulated lymphocytes. The change of lymphocyte proliferation by PLA2, was parallel to the change of percentage of helper T cells. Furthermore--a CD4-rich population was proved more susceptible to PLA2 effect than a CD8-rich population. Para-bromophenacyl bromide (pBPB), an irreversible inhibitor of PLA2, abrogated the biphasic effect of PLA2 on PHA MNC proliferation. These results suggest that PLA2 plays a regulatory role on immune reactions by modulating the percentage of helper T cells.  相似文献   
22.
The microcirculatory architecture of normal tissue, transitional mucosa and adenocarcinoma of the human colon was investigated with microvascular corrosion casting (MVCC) combined with scanning electron microscopy (SEM). The study showed that the capillaries within the normal mucosa were arranged in a regular hexagonal pattern around the mucosal glands and that the microvessels of transitional mucosa mostly had lost the typical hexagonal pattern and become slightly wider in diameter. The microvessels in the tumor periphery were increased in number and disorganized, and presented large variation in morphology with claw-like formations, widened sinuses, diverticula and appendixoid patterns. Microvessels were lacking in the central areas of tumors. These morphological alterations may serve as additional indicators of tumor development.  相似文献   
23.
开放手术观察腰椎间盘突出症溶核失败45例分析   总被引:2,自引:2,他引:0  
目的 通过开放手术观察分析椎间盘髓核化学溶解术治疗腰椎间盘突出症失败原因。方法 收集溶核失败的腰椎间盘突出症45例行开放手术治疗。结果 术中见45例硬膜外脂肪完全消失,43例髓核未见溶解,2例髓核溶解呈糊状但未被吸收,21例伴有侧隐窝狭窄,15例突出物与神经根粘连,20例黄韧带增厚,2例椎管骨性狭窄,14例突出物钙化。结论 腰椎间盘突出症病变间隙合并有侧隐窝狭窄、神经根粘连、椎管狭窄、突出物钙化等,不是溶核治疗的适应证。  相似文献   
24.
25.
A case of a paraffinoma in the urinary bladder is presented. Plain radiography and intravenous urography showed a low attenuation filling defect in the urinary bladder, and CT demonstrated a lobulated fat-attenuation mass floating in the urinary bladder.  相似文献   
26.
Sonographic findings in 16 cases of Krukenberg tumor from gastric carcinoma were analyzed. The patients' ages ranged from 25 to 52 years (mean 42 years). The tumor involved both ovaries in 14 patients with asymmetrical masses in 9 of 14 cases. Ascites was noted in 15 cases. Echogenicity of the tumor varied from solid to predominantly cystic: solid in 8, mixed in 6, and predominantly cystic in 2 cases. Solid masses tended to be smaller than mixed or cystic masses. The primary gastric carcinoma had been diagnosed before emergence of the tumors in only 7 cases. The findings suggest that in relatively young patients with ovarian mass, particularly bilateral tumors, careful evaluation for gastrointestinal tract involvement should be done.  相似文献   
27.
目的 测定颅内动脉瘤夹闭前后血中S1 0 0B蛋白含量 ,研究异氟醚控制性降压对脑功能的影响。方法 择期颅内动脉瘤夹闭术病人 30例 ,ASAⅠ~Ⅱ级 ,随机分为两组 :异氟醚降压组 (n=1 5 )和异氟醚非降压组 (n =1 5 )。非降压组术中吸入 1MAC异氟醚维持麻醉。降压组行异氟醚控制性降压 ,平均动脉压下降幅度 30 %~ 4 0 % ,夹闭动脉瘤后降低异氟醚吸入浓度 ,终止降压。分别于切皮前、动脉瘤夹闭后即刻、2、4h、术后第 1、2天取血测定S1 0 0B蛋白含量 ,并于术后 1周随访病人 ,记录有无术后神经系统并发症。结果  (1 )异氟醚降压后 30min平均动脉压由诱导前的 (95 2± 1 2 3)mmHg降至 (5 8 8± 5 4 )mmHg ,停止降压后 30min血压回升至 (75 1± 8 3)mmHg。降压后外周血管阻力及心肌收缩加速度下降 ,但心率及心输出量均无显著性变化 ;(2 )异氟醚降压组与非降压组间同一时间点血中S1 0 0B蛋白浓度无明显差异。降压组术后第 1天及第 2天血中S1 0 0B蛋白浓度均显著升高 (F =2 94 4 ,P =0 0 1 8)。结论 在颅内动脉瘤夹闭术中应用异氟醚控制性降压可能加重了术后脑损伤 ,不利于病人围麻醉期脑功能的保护  相似文献   
28.
目的:探讨不同培养阶段骨髓基质干细胞成骨能力的变化及BMP-2对其成骨能力的影响。方法:培养兔骨髓基质干细胞,测定第3代和第18代细胞碱性磷酸酶及骨钙素活性;测定BMP-2对不同培养时间骨髓基质干细胞成骨能力的影响;测定rhBMP-2对细胞增殖的影响。结果:细胞传至第18代后,分泌的骨钙素(OC)水平及ALP活力明显降低,与第3代细胞相比,差异显著(P〈0.05)。第3代细胞在rhBMP-2的诱导下,分泌的OC水平及ALP活力在原基础上进一步升高,与对照组相比,差异显著(P〈0.05)。结第18代细胞在rhBMP-2的诱导下,分泌的OC水平及ALP活力在原基础上升高,与对照组相比,差异不显著(P〉0.05);随培养时间的延长,各组细胞数量均有所增加,rhBMP-2诱导组与对照组细胞无显著性差异(P〉0.05)。细胞的传代次数对细胞增殖无明显影响(P〉0.05)。结论:rhBMP-2对细胞增殖无影响。随着传代次数的增加,骨髓基质干细胞的成骨能力下降,rhBMP-2促进其成骨的能力亦下降。  相似文献   
29.
We present a case of benign osteoblastoma of the occipital bone. Benign osteoblastoma is an uncommon primary bone tumor, which usually involves the vertebrae and the long bones. This tumor rarely develops in the calvaria, showing a preference for the temporal and frontal bones when it does. To the best of our knowledge, this case is only the eighth reported case of benign osteoblastoma confined to the occipital bone. A 20‐year‐old male presented with a mild tender mass lesion of the occipital area, just below the lambda. Plain X‐ray films and CT scans demonstrated an osteolytic mass surrounded by the sclerotic rim within the diploic space. MRI proved to be effective for the evaluation of the intracranial and intraosseous extensions of the tumor. However, it was very difficult to formulate a differential diagnosis against other osteoblastic tumors, or osteoid osteoma, in view of its radiological appearance. The final diagnosis was obtained by careful consideration of the histopathological characteristics of the tumor combined with its clinical and radiological features. Although generally regarded as benign, a complete resection is preferred over conventional curettage as this can guard against possible recurrence and malignant transformation.  相似文献   
30.
本文用限制性内切酶分析(REA)作伴放线放线杆菌(Aa)的鉴定和分型研究,提取Aa染色体DNA,井分别用BamHI、HindⅢ,Sal Ⅰ和Xho Ⅰ消化,作琼脂糖凝胶电泳。结果显示,Aa和嗜沫嗜血杆菌的DNA片段图谱明显不同;分属于两种不同血清型的两株Aa菌株,其DNA片段图谱也明显不同。这表明,REA可用于Aa菌的鉴定和分型,在所用的4种酶中,以Sal Ⅰ和Xho Ⅰ消化的DNA片段图谱差异最明显。  相似文献   
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