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101.
急性脑梗塞患者血清肿瘤坏死因子水平变化的观察   总被引:7,自引:0,他引:7  
采用双抗体夹心ELISA法对30例正常对照和36例急性脑梗塞患者血清肿瘤坏死因子(TNF)水平进行了检测。结果显示:急性脑梗塞组血清TNF水平显著高于正常对照组,血清TNF水平变化与脑梗塞容积大小密切相关,恢复期血清TNF水平显著降低。结果提示,TNF参与了脑梗塞发生后病理变化过程,检测血清TNF对判定脑梗塞容积大小有一定的临床意义。  相似文献   
102.
In an open, randomized cross-over study in 124 patients, we compared the efficacy, safety and patient preference of oral and subcutaneous sum triptan in the acute treatment of migraine. Patients were treated for 3 attacks or 3 months and then crossed over. Primary clinical efficacy was defined as a reduction in headache severity on a four-point self-rating scale from severe (3) or moderate (2) to mild (1) or none (0), or mild (1) to none (0). Efficacy was evaluated 2 h after the administration of subcutaneous and 4h after the administration of oral sumatriptan. Subcutaneous sumatriptan was significantly more effective than oral sumatriptan in relieving headache (over all three attacks 78% vs 61% improvement), improving clinical disability (55% vs 41 % improvement) and relieving nausea (69% vs 53%), vomiting (72% vs 32%) and phono- or photophobia (67% vs 49%). Median time to recurrence was shorter after subcutaneous (12.5 h) than after oral sumatriptan (18 h); the number of patients experiencing a recurrence was similar Patients reported more adverse events after subcutaneous sumatriptan (1.32 per attack) than after the oral form (0.85 per attack), but all adverse events were mild to moderate in intensity and of short duration. Patient opinion was more often positive after subcutaneous sumatriptan. These results may be useful in counselling patients to choose between the available marketed formulations of sumatriptan.  相似文献   
103.
Conclusion The mechanisms that regulate regeneration of kidney epithelial cells after acute tubular necrosis are poorly understood. Repair of the nephron can take place in the adverse systemic metabolic setting caused by failure of renal function. This clinical observation suggests that factors released at the site of the tubular insult can mediate repair. Studies carried out in this and other laboratories show that kidney epithelial cells can release and respond to polypeptide growth factors which may thereby contribute to renal regeneration by autocrine and paracrine mechanisms. Specific growth factors secreted by cells and deposited in the tubular basement membrane prior to injury may subsequently participate in nephron repair. In addition, adenine nucleotides released from injured or dying cells at the injury site or provided exogenously could stimulate surviving renal epithelial cells at the edges of the wound to migrate along the basement membrane to rapidly reepithelialize the nephron and subsequently initiate mitogenesis to replace cells lost by necrosis.The nephrotoxic effect of many agents used in cancer chemotherapy and the older age of patients undergoing complicated surgical procedures has increased the incidence of ARF, whereas the mortality rate has not changed since the early 1950s [22]. Thus there is considerable need for innovative therapeutic strategies. An important goal of future research efforts is to identify new growth factors that facilitate migration, differentiation, and proliferation of renal epithelial cells at sites of tubular necrosis. Isolation and use of these agents in combination with dialysis and nutritional support could speed renal regeneration and thereby improve the outcome in patients with this condition.Abbreviations ARF acute renal failure - ECM extracellular matrix - EGF epidermal growth factor - FGF fibroblast growth factor - IGF insulin-like growth factor - MGSA melanocyte growth-stimulating activity - PDGF platelet-derived growth factor - IGF transforming growth factor  相似文献   
104.
急性中风中脏腑证型与垂体-肾上腺轴激素关系的研究   总被引:6,自引:0,他引:6  
目的 :探讨急性中风中脏腑证型与垂体—肾上腺轴激素的促肾上腺皮质激素 (ACTH)、皮质醇 (CS)的关系。方法 :对 78例中脏腑患者进行辨证分型 ,同时利用放射免疫分析 (RIA)法测定血中 ACTH、CS含量 ,按证型分为四组 ,对比不同证型间 ACTH、CS的水平 ,并与健康人组 (60例 )作对照。结果 :ACTH、CS含量水平比较 :1四种证型的 ACTH、CS均比正常健康人组高 (P <0 .0 0 1 ) ;2四种证型间比较有明显差异 (P<0 .0 1 ) ,从高到低为 :痰热内闭心窍证 >风火上扰清窍证 >痰湿蒙塞心神证 >元气败脱、心神散乱证。结论 :ACTH、CS含量水平可作为判别中脏腑不同证型间的微观指标  相似文献   
105.
106.
硝基胍的毒性研究   总被引:2,自引:1,他引:1  
目的对硝基胍的毒性进行研究,为制订卫生标准提供依据.方法包括急性毒性试验、蓄积毒性试验及亚慢性毒性试验.结果硝基胍大鼠经口LD50为8 066 mg/kg,小鼠经口LD50为10 044 mg/kg,蓄积系数大于5.3.亚慢性毒性试验中,高剂量组雄性大鼠在染毒第3周和第8周,体重有明显的负增长(P<0.05);高剂量组雄性大鼠睾丸脏器系数明显高于对照组(P<0.05);红细胞免疫功能测定结果显示,中、高剂量组大鼠红细胞受体花环率分别为10.00±2.37和7.50±2.66,明显低于对照组(P<0.05,P<0.01).其余各项指标未见明显改变.结论硝基胍属于微毒级毒物,轻度蓄积,亚慢性毒性试验对动物有一定的影响.  相似文献   
107.
A simple method for screening assessment of acute toxicity of chemicals   总被引:1,自引:0,他引:1  
We proposed a simple method for screening assessment of acute oral and dermal toxicity using only three rats and mice of each sex at each dose level. Animals were first treated with chemicals at a dose of 2000 mg/kg and were carefully observed for compound-related morbidity and mortality. If none of the animals died, the following toxicity tests were suspended. If some of the animals died, toxicity tests at doses of 200 and 20 mg/kg were performed. The approximate LD50 values calculated by this method showed little difference between two separate laboratories and were in good agreement with LD50 values reported in the literature. Our toxicological data also showed that LD50 values were about 2–2.5 times the MNLD (maximum non lethal dose) in acute oral and dermal toxicity. This meant that a chemical could be regarded as having an LD50 of about 4000 mg/kg or higher when there was no mortality at the dose of 2000 mg/kg. A chemical with such low toxicity would not require further testing for lethal effects. Therefore, this simple method combining the fixed-dose procedure with the limit test is suitable for determination of approximate LD50 values of chemicals and for screening for necessity for classical full LD50 test using many animals.This work was supported by a grant from Ministry of Health and Welfare in Japan (No. 467 and 511)  相似文献   
108.
甘肃省1995年共报告15岁以下儿童急性弛缓性麻痹(AFP)病例90例,发病率为1.32/10万。省脊髓灰质炎(脊灰)实验室收到AFP病例的粪便标本共79例,占88%;双份合格粪便标本采集率为68%(61/90);粪便标本7天内送省脊灰实验室的占65%(52/79)收到粪便标本后7天内分离培养的占89%(70/79);分离培养结果及时报告率为87%(69/79)。病毒分离阳性率13.92%(11/79),其中脊灰病毒(PV)Ⅱ型5株,Ⅲ型1株,非脊灰肠道病毒(NPEV)5株。收到AFP病例密切接触者粪便标本3l8份,病毒分离阳性率5.66%(18/318),其中PVⅡ型8株,NPEV10株。全部送检粪便标本NPEV分离率3.78%(15/397)。所分离的PV均为疫苗株,且Ⅱ型居多。  相似文献   
109.
BACKGROUND: Consistent evidence has indicated that air pollution increases the risk of cardiovascular diseases. The underlying mechanisms linking air pollutants to increased cardiovascular risk are unclear. OBJECTIVES: We investigated the association between the pollution levels and changes in such global coagulation tests as the prothrombin time (PT) and the activated partial thromboplastin time (APTT) in 1218 normal subjects from the Lombardia Region, Italy. Plasma fibrinogen and naturally occurring anticoagulant proteins were also evaluated. METHODS: Hourly concentrations of particulate (PM10) and gaseous pollutants (CO, NO2, SO2, and O3) were obtained from 53 monitoring sites covering the study area. Generalized additive models were applied to compute standardized regression coefficients controlled for age, gender, body mass index, smoking, alcohol, hormone use, temperature, day of the year, and long-term trends. RESULTS: The PT became shorter with higher ambient air concentrations at the time of the study of PM10 (coefficient = -0.06; P < 0.05), CO (coefficient = -0.11; P < 0.001) and NO2 (coefficient =-0.06; P < 0.05). In the 30 days before blood sampling, the PT was also negatively associated with the average PM(10) (coefficient = -0.08; P < 0.05) and NO2 (coefficient = -0.08; P < 0.05). No association was found between the APTT and air pollutant levels. In addition, no consistent relations with air pollution were found for fibrinogen, antithrombin, protein C and protein S. CONCLUSIONS: This investigation shows that air pollution is associated with changes in the global coagulation function, suggesting a tendency towards hypercoagulability after short-term exposure to air pollution. Whether these changes contribute to trigger cardiovascular events remains to be established.  相似文献   
110.
急性肠系膜静脉血栓形成16例临床分析   总被引:1,自引:0,他引:1  
目的 分析急性肠系膜静脉血栓形成 (ASMVT)的临床特征和诊断方法。方法 对北京友谊医院 1985年 10月至 2 0 0 2年 10月确诊的 16例ASMVT的临床资料进行分析 ,并结合文献 ,总结ASMVT的临床特征和诊断方法。结果 16例ASMVT患者 ,年龄 19~ 6 4岁 (平均 4 5 9岁 )。主要症状有腹痛 ( 16 / 16 )、腹胀 ( 16 / 16 )、呕吐 ( 10 / 16 )、发热 ( 8/ 16 ) ,主要体征有腹部膨隆 ( 16 / 16 )、腹膜刺激征( 16 / 16 )。误诊率 75 % ( 12 / 16 ) ,死亡率 4 4 % ( 7/ 16 )。结论 ASMVT的临床表现有一定的特征 ,早期彩色超声检查、诊断性腹腔穿刺、结合CT或肠系膜上动脉造影异常发现可对ASMVT做出正确的诊断 ,早期手术可以降低死亡率  相似文献   
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