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21.
ClassIinterferonisapotent1mmunemodu-latingfactorinvivo,andplaysanimportantrolelnactivatinganti-tumorcytotoxicTlymphocytesandnonuspecificeffectorcellssuchasNKcellsLlJ.ln-terferonandmanyothercytokinegeneswereintro-ducedintotumorcells,tumorinterstitialcellsandtumorinfiltratinglymphocytes['-']inordertosustainaneffectiveanti-tumorconcentrationofcy-tokinelocatedattumorsites.Itwasshownthatsomecytokinegenemodifiedtumorcellslosttheirtumorigenicityandinhibitedthegrowthofparentaltumorinanimalmodels.Pra… 相似文献
22.
亚低温对戊四氮诱导癫痫发作的影响 总被引:1,自引:0,他引:1
目的观察戊四氮诱导癫痫发作的形式变化及不同温度下癫痫大鼠海马组织病理学的变化和计数CA3区残存的神经元数量.方法雄性SD大鼠分为上述不同温度的四组,用冰袋降温、白炽灯泡升温的方法来控制温度.将控制好温度的大鼠用戊四氮诱导癫痫发作,在相同的时间内观察大鼠发作形式的变化.HE染色后观察海马区组织病理学的改变,并选择组织学损害最明显的区域在高倍镜(40×10)下计数神经元的丢失.结果高温状态下癫痫发作程度最重,神经元丢失最严重,低温下癫痫发作程度较轻,神经元丢失也较少,亚低温下癫痫发作程度最轻,持续时间也最短,神经元丢失最少.结论亚低温对癫痫大鼠有脑保护作用. 相似文献
23.
基数口服药盒的设计与应用 总被引:1,自引:0,他引:1
基数口服药是临床各科室必须储备的药品,以备病区住院病人非正常工作时间或急诊使用.病区小药柜常常根据专科特点配备不同种类、数量的基数口服药,其特点是基数少、品种多、专科性强、用量不定. 相似文献
24.
Inhibitory Effect of Angiogenesis Inhibitor TNP—470 on Human ACHN Renal Cell Carcinoma 总被引:2,自引:0,他引:2
Angiogenesis,the formation of new bloodvessels,is necessary for the growth of tumors andtheir metastasis.TNP- 470 is a synthetic analogueof fumagillin and has stronger antiangiogenic ac-tivity and less side- effects than fumagillin.Thiscompound has been reported to suppress the prolif-eration and metastasis of various kinds of tu-mors[1] . Using nude mice xenografts of ACHN hu-man renal cell carcinoma ( RCC) ,the presentstudyattempted to examine the action of TNP- 470 ongrowth,metastasi… 相似文献
25.
目的 对兔心肌缺血的模型制备方法进行改进 ,并探讨其在 MRI诊断研究中的价值。方法 分别采用高位结扎左冠状动脉前降支 (L AD)和同时低位结扎 L AD及左冠状动脉旋支 (L Cx)建立兔心肌梗塞模型 ,并在术后行 MRI检查 ,对取材后心肌标本行氯化三苯四氮唑 (TTC)及病理检查。结果 1L AD组 2 0 % (5 / 2 5 )发生心室颤动导致死亡 ,L AD +L Cx组无一例发生室颤死亡。 2 L AD组 EKG改变明显者占 5 6 % (14 / 2 5 ) ,其中 2 1.4 3% (3/14 )在即刻就有 EKG明显改变 ,并在 30分钟后恢复正常 ;EKG改变不明显者占 4 4 % (11/ 2 5 ) ;L AD +L Cx组 10 0 %有 EKG明显改变 ,且 30分钟后亦无明显恢复。 3L AD组心肌梗塞范围较小 ,并均限于左室前壁 ,室间隔前部损害 ;而 L AD+L Cx组心肌梗塞范围较大 ,且累及左室前壁及侧壁 ,无一例有室间隔前部损害。4 L AD组中有 30 % (6 / 2 0 )不能显示小灶缺血局部心肌运动降低 ,16 .6 7% (3/ 18)无法分辨早期小梗塞灶的 MRI信号变化 ;而 L AD+L Cx组均能显示缺血局部心肌运动降低及梗塞灶早期的 MRI信号变化。结论 低位结扎兔心 L AD+L Cx,手术死亡率低 ,EKG改变明显 ,梗塞面积较大 ,是 MRI研究中一种较理想的心肌缺血动物模型制备方法。 相似文献
26.
Karen M Majchrzak Lara B Pupim Kong Chen Cathi J Martin Sheila Gaffney Jane H Greene T Alp Ikizler 《Journal of renal nutrition》2005,15(2):217-224
OBJECTIVE: To determine physical activity patterns in chronic hemodialysis patients with a specific emphasis on the difference between dialysis and nondialysis days. Design A cross-sectional single-center study. SETTING: Vanderbilt University Outpatient Dialysis Unit. PATIENTS: Twenty current chronic hemodialysis patients: 10 male, 10 female; 15 black, 5 white; mean age, 50.1 +/- 9.9 years; height, 164.5 +/- 10.9 cm; weight, 82.5 +/- 15.4 kg; length on dialysis, 57.3 +/- 45.3 months. METHODS: Minute-by-minute physical activity was assessed over a 7-day period using a triaxial accelerometer, which consists of raw numbers or counts calculated by the 3 axes of the accelerometer (PA counts). PA counts were extrapolated on a daily and hourly basis. Physical functioning tests included: sit-to-stand, 6-minute walk, and 1-repetition maximal leg press exercise. Laboratory values for serum concentrations of albumin, prealbumin, C-reactive protein, and cholesterol were also collected. MAIN OUTCOME MEASURE: PA counts. RESULTS: Total PA counts were significantly lower on dialysis days when compared with nondialysis days (128,279 +/- 74,009 versus 168,744 +/- 95,168, respectively, P = .025). The average PA counts during the 4-hour dialysis time period were significantly lower on dialysis days when compared with nondialysis days (3,086 +/- 3,749 versus 11,070 +/- 7,695, respectively, P = .001). At postdialysis hours 1 and 2, PA counts on dialysis days were significantly higher than on nondialysis days (11,410 +/- 5,340 versus 9,082 +/- 6,646, P = .008, and 14,048 +/- 9,728 versus 8,662 +/- 6,433, P = .016, respectively). By postdialysis hour 4, PA counts on dialysis days had significantly decreased when compared with nondialysis days (6,068 +/- 6,268 versus 10,512 +/- 7,420 PA counts, P = .01, respectively). From postdialysis hours 5 to 20, there was no significant difference in PA counts between dialysis and nondialysis days. CONCLUSION: This study shows that physical activity is lower on dialysis days when compared with nondialysis days, and this decrease is caused by the lack of activity during the 4-hour hemodialysis procedure. New behavior modification strategies involving physical activity, both during hemodialysis and on nondialysis days, must be examined in this patient population. 相似文献
27.
将SRSV/3T3细胞DNA转染NIH/3T3细胞,转染后17d,实验组出现18个集落,对照组出现4个集落。将实验组集落细胞接种于3只BALB/C裸鼠皮下,全部长成纤维肉瘤。将SRSV/3T3细胞DNA用EcoRI和BamHI酶切电泳,分别应用5种癌基因(v-myc、KJ-ras、v-src、v-sis和e-fos)作Southern印迹和分子杂交。发现SRSV/3T3细胞DNA的BamHI酶切片段与c-fos探针杂交后,在2.2~3.0 kb处出现阳性杂交带。应用c-fos单抗检测转化细胞,细胞核内呈阳性反应。表明SRSV/3T3细胞DNA含有fos样转化基因,在转化细胞内有此基因的过度表达。 相似文献
28.
Sung-Eun Kong Lewis R. Blennerhassett Kathryn A. Heel Rosalie D. McCauley John C. Hall 《ANZ journal of surgery》1998,68(8):554-561
Ischaemia-reperfusion injury (IRI) is of obvious relevance in situations where there is an interruption of blood supply to the gut, as in vascular surgery, or in the construction of free intestinal grafts. It is now appreciated that IRI also underlies the gut dysfunction that occurs in early shock, sepsis, and trauma. The events that occur during IRI are complex. However, recent advances in cellular biology have started to unravel these underlying processes. The aim of this review is to provide an outline of current knowledge on the mechanisms and consequences of IRI. Initially, IRI appears to be mediated by reactive oxygen metabolites and, at a later stage, by the priming and activation of polymorphonuclear neutrophils (PMN). Ischaemia-reperfusion injury can diminish the barrier function of the gut, and can promote an increase in the leakage of molecules (intestinal permeability) or the passage of microbes across the wall of the bowel (bacterial trans-location). Ischaemia-reperfusion injury to the gut can result in the generation of molecules that may also harm distant tissues. 相似文献
29.
30.
Coronary vasomotion in patients with syndrome X: evaluation with positron emission tomography and parametric myocardial perfusion imaging 总被引:1,自引:1,他引:0
Joan G. Meeder Paul K. Blanksma Ernst E. van der Wall Antoon T. M. Willemsen Jan Pruim Rutger L. Anthonio Richard M. de Jong Willem Vaalburg Kong I. Lie 《European journal of nuclear medicine and molecular imaging》1997,24(5):530-537
The aim of this study was to elucidate further the causative mechanism of abnormal coronary vasomotion in patients with syndrome X. In patients with syndrome X, defined as angina pectoris and documented myocardial ischaemia during stress testing with normal findings at coronary angiography, abnormal coronary vasomotion of either the micro- or the macrocirculation has been suggested as the causative mechanism. Accordingly, we evaluated endothelial function, vasodilator reserve, and perfusion heterogeneity in these patients. Twenty-five patients with syndrome X (definitely normal coronary arteriogram, group A), 15 patients with minimal coronary artery disease (group B) and 21 healthy volunteers underwent [13N]ammonia positron emission tomography at rest, during cold pressor stimulation (endothelial function) and during dipyridamole stress testing (vasodilator reserve). Heterogeneity of myocardial perfusion was analysed by parametric polar mapping using a 480-segment model. In both patient groups, resting perfusion was increased compared to the normal subjects: group A, 127±31 ml·min–1·100 g–1; group B, 124±30 ml·min–1·100 g–1 normal subjects, 105±21 ml·min–1·100 g–1 (groups A and B vs normals,P<0.05). These differences were abolished after correction for rate-pressure product. During cold pressor stimulation, the perfusion responses (ratio of cold pressor perfusion to resting perfusion) were similar among the patients and the control subjects (group A, 1.20±0.23; group B, 1.24±0.22; normal subjects, 1.23±0.14). Likewise, during dipyridamole stress testing, perfusion responses were similar among the three groups (group A, 2.71±0.67; group B, 2.77±1.29; normal subjects, 2.91±1.04). In group A the heterogeneity of resting perfusion, expressed as coefficient of variation, was significantly different from the volunteers (20.1±4.5 vs 17.0±3.0,P<0.05). In group B (coefficient of variation 19.4±3.9) the difference from normal volunteers was not significant. In this study, patients with syndrome X and patients with minimal coronary artery disease showed normal perfusion responses during cold pressor stimulation and dipyridamole stress testing. Our findings therefore suggest that endothelial dysfunction and impaired vasodilator reserve are of no major pathophysiological relevance in patients with syndrome X. Rather, other mechanisms such as increased sympathetic tone and focal release of vasoactive substances may play a role in the pathogenesis of syndrome X. 相似文献