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21.
BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxygenation is also one of them. OBJECTIVE: To observe the influence of moderate hypothermia on cerebral oxygenation of animals with acute intracranial hypertension, and further investigate the protective mechanism of moderate hypothermia. DESIGN: A randomized controlled trial. SETTING: Department of Neurosurgery, Renji Hospital affiliated to the Medical College of Shanghai Jiao Tong University. MATERIALS: Twenty healthy little pigs, either male or female, weighing 4.5–5.5 kg, were used. Neurotrend-typed multiparameter monitoring system (Diametrics Company, British); CMA/100 micro-injection pump (Carnegie Company, Sweden). METHODS: The experiment was conducted in the Changzheng Hospital affiliated to the Second Military Medical University of Chinese PLA in November, 2001. The pigs were randomized into two groups: the normothermia group (control group, n =10) and moderate hypothermia group (n =10). ① Bilateral femoral arteries were separated, one was connected to pressometer for monitoring mean arterial pressure (MEP), and the other for analysis of blood gases [including peripheral blood pH value, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of carbon dioxide (PaCO2), HCO3–]. ② Rectal temperature was monitored with mercurial thermometer. ③ Intracranial pressure was monitored using Camino optic ICP probe placed in the subdural space. ④ Neurotrend multiparameter monitoring sensor was inserted into the white matter for about 4 cm to determine cerebral perfusion pressure (CPP, CPP=MAP(ICP), brain tissue partial oxygen pressure (PO2), partial pressure of carbon dioxide (PCO2), HCO3– and brain temperature. The rectal temperature of animals in the moderate hypothermia group was lowered to 34 ℃ using ice bags, and the body temperature was maintained at 33–35 ℃ for 2 hours. The changes of the parameters were observed continuously, and the pigs in the normothermia group were not treated with cooling. MAIN OUTCOME MEASURES: ① MAP, ICP, rectal temperature, CCP; Indexes of cerebral oxygenation detected with Neurotrend-typed multiparameter monitoring system; ② Results of blood gases analysis in the moderate hypothermia group. RESULTS: All the 20 pigs were involved in the analysis of results. ① MAP, ICP, rectal temperature, CCP and indexes of cerebral oxygenation: In the moderate hypothermia group, the ICP after cooling was obviously lower than that before cooling [(3.31±1.19), (5.33±0.95) kPa, P < 0.05], CCP was higher, brain tissue PCO2 [(12.03±1.73), (10.59±2.01) kPa, P < 0.05], and brain tissue pH value was higher [(7.03±1.63), (9.40±1.30) kPa, P < 0.05], whereas the brain temperature was decreased as compared with that before cooling [(34.9±0.3), (37.2±0.2) ℃, P < 0.05]. ② Results of blood gases analysis in the moderate hypothermia group: There were no significant differences in the parameters of peripheral arterial blood gases analysis before and after cooling in the moderate hypothermia group (P > 0.05) CONCLUSION: Moderate hypothermia will not impair the cerebral oxygenation, and it can reduce brain tissue CO2 and decrease brain tissue acidosis.  相似文献   
22.
OBJECTIVE: To evaluate the relationship between the left ventricular hypertrophy (LVH) and the ambulatory pulse pressure and aortic root dimension (AOD) in essential hypertensive patients. METHODS: We monitored the 24-hour ambulatory blood pressure and applied echocardiography in 107 essential hypertensive patients. Using the left ventricular mass index (LVMI) as an index in evaluating LVH, the patients were divided into 2 groups: 29 cases in the LVH group and 78 in the non-LVH group. RESULTS: The average levels of 24-hour pulse pressure, daytime pulse pressure, nighttime pulse pressure and AOD were significantly different between patients with LVH and without LVH (P < 0.05). Multiple stepwise regression analysis showed that the changes in nighttime pulse pressure and AOD were closely related to LVMI (P < 0.001). CONCLUSION: The pulse pressure and AOD are important factors leading to LVH in patients with essential hypertension.  相似文献   
23.
Cooking processes that gelatinize granules or disrupt structure might increase the glucose and insulin responses because a disruption of the structure of starch by gelatinization increases its availability for digestion and absorption in the small intestine. We hypothesized that the uncooked form of rice, which has a relatively low degree of gelatinization even though in powder form, would result in lower metabolic glucose and insulin responses compared with cooked rice (CR). To assess the effects of the gelatinization of rice on metabolic response of glucose and insulin, we investigated the glucose and insulin responses to 3 rice meals of different gelatinization degree in female college students (n = 12): CR (76.9% gelatinized), uncooked rice powder (UP; 3.5% gelatinized), and uncooked freeze-dried rice powder (UFP; 5.4% gelatinized). Uncooked rice powders (UP and UFP) induced lower glucose and insulin responses compared with CR. The relatively low gelatinization degree of UPs resulted in low metabolic responses in terms of the glycemic index (CR: 72.4% vs UP: 49.7%, UFP: 59.8%) and insulin index (CR: 94.8% vs UP: 74.4%, UFP: 68.0%). In summary, UPs that were less gelatinized than CR induced low postprandial glucose and insulin responses.  相似文献   
24.
王成荣研究员长于以中医药诊治子宫内膜异位症(EMT),根据其临床经验认为“火热致瘀”是EMT的基本病因、病机,且火热与瘀血互为因果、恶性循环,致使EMT病程缠绵不愈、反复复发。王老据此提出“清热解毒、化瘀散结”的治疗法则,为治疗EMT开辟了另一思路和理论。  相似文献   
25.
目的建立滑膜炎颗粒剂中原儿茶醛的含量测定方法质量。方法采用高效液相色谱法对方中原儿茶醛进行含量测定。结果高效液相色谱法测定结果表明原儿茶醛在0.1005~1.005μg范围内呈线性关系,平均加样回收率为99.22%;RSD为0.72%。结论本法简便,重现性好、结果可靠,可作为控制滑膜炎颗粒剂的质量方法。  相似文献   
26.
荧光示踪法研究逆行岛状皮瓣静脉回流   总被引:3,自引:0,他引:3  
目的探讨采用荧光示踪法研究逆行岛状皮瓣静脉回流的可行性,并初步观察静脉回流规律。方法20只新西兰大白兔,每只取耳静脉血0.ImL,分离RBC并用FITC标记。流式细胞仪检测已标记的RBC阳性率及荧光强度,倒置荧光显微镜观察其形态。取20只新西兰大白兔,在动物双侧后肢内侧分别建立4cm&#215;3cm隐动、静脉逆行岛状皮瓣模型(n=10)和顺行岛状皮瓣模型(n=10),血管蒂长3cm。将一侧后肢随机设定为实验组,皮瓣制备后注射已标记的RBC悬液5pL;对侧为对照组,不注射示踪剂。实验组按顺行和逆行皮瓣分成两组,即顺行皮瓣组和逆行皮瓣组,每组10个;再根据注入示踪剂途径不同,分为动脉和静脉2个亚组,每亚组5个皮瓣。注射示踪剂5S后取下皮瓣立即冷冻,取连续的3张冰冻切片(5~7pm),其中2张行HE染色和GENMED染色,另]张不染色直接压片,荧光显微镜观察荧光分布。结果流式细胞仪分析FITC标记的RBC阳性率在99%以上,荧光强度均≥10。;倒置荧光显微镜下标记的RBC呈均匀分布的绿色荧光,荧光强度均匀、稳定。冰冻切片显示实验组皮瓣蒂部均出现荧光,对照组未见荧光。顺行岛状皮瓣组荧光主要分布在静脉腔、静脉壁、动脉内膜和外膜;逆行岛状皮瓣组荧光分布在动脉内膜、外膜和静脉壁。结论荧光示踪剂可用于静脉回流研究,顺行岛状皮瓣静脉主要通过静脉腔、静脉壁、动脉内膜和外膜回流;逆行岛状皮瓣静脉主要通过动脉内膜、外膜和静脉壁的“迷宫式途径”回流。  相似文献   
27.
目的利用MR显微成像技术研究阿尔茨海默病转基因小鼠老年斑的沉积情况。方法2只17个月龄阿尔茨海默病转基因[V717I]小鼠和2只野生型小鼠,行活体T2WI,然后对照影像定位结果进行组织学切片及免疫组织化学染色。观察T2WI中老年斑的沉积情况以及其与免疫组织化学染色结果的对应关系。结果转基因小鼠T2WI上显示大脑皮层和海马区可见点状低信号,且部分低信号可以和组织学切片所显示的老年斑相对应;野生型小鼠T2WI未见明显的低信号,免疫组织化学染色也未见到染色阳性的斑块。结论MR显微成像技术检测老年斑的沉积是可行的,且可用来特异性地诊断阿尔茨海默病。  相似文献   
28.
后腹腔镜治疗肾上腺肿瘤35例临床分析   总被引:15,自引:9,他引:6  
目的总结后腹腔镜技术治疗肾上腺肿瘤的临床经验.方法采用后腹腔镜切除肾上腺肿瘤35例,男12例,女23例.年龄25岁~72岁,平均49.8岁.左侧15例,右侧20例.其中嗜铬细胞瘤5例,原发性醛固酮增多症10,柯兴氏病2例,神经节细胞瘤2例,无功能性腺瘤16例.腰部取3个套管针穿刺入路,用自制的水囊扩张器扩张后腹腔,用超声刀将肿瘤切除.结果 35例手术均成功,无中转开放手术病例.术中出血量10~500 ml,平均74 ml.病人均未输血.手术时间45~200 min,平均90 min.结论后腹腔镜手术切除肾上腺肿瘤手术效果确切,手术时间短,术中出血少,损伤小,术后恢复快,可以替代绝大多数肾上腺肿瘤开放手术.  相似文献   
29.
We thank Drs Liu and Li for their interest in our randomizedtrial investigating the anti-arrhythmic effect of perindopriland losartan in the setting of lone paroxysmal atrial fibrillation(AF). While agreeing on modification of atrial remodelling asthe  相似文献   
30.
骨髓基质干细胞修复兔关节软骨缺损的实验研究   总被引:1,自引:1,他引:0  
目的研究以多聚乙醇酸(PGA)为支架的骨髓基质干细胞(BMSCs)复合物修复兔膝关节软骨缺损的情况。方法体外培养扩增的自体BMSCs种植于PGA支架并培养72h,然后将支架-细胞复合物植入兔关节软骨缺损模型。术后12周处死动物,标本行大体观察、组织学检查及Ⅱ型胶原免疫组化染色。结果BMSCs-PGA复合物植入后形成丰富的透明软骨样修复组织,新生软骨无明显退变。对照组主要为纤维组织及软骨下骨修复。结论BMSCs-PGA复合物可修复关节软骨缺损。  相似文献   
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