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991.
观察了大鼠急性缺氧前后血浆和呼出气一氧化氮(NO)含量的变化,结果显示,动物吸人10%,20min后,血浆NO_2/NO_3浓度从23.56±7.13升至41.63±10.10μmol/L(P<0.01);呼出气NO浓度出0.099±0.055增至0.162±0.108ppm(P<0.01).提示急性缺氧时NO生成增多可能在缺氮性肺血管收缩(HPV)中起调节作用。为探讨吸入NO对HPV的影响,本文采用人工呼吸给缺氧大鼠吸入40ppmNO,发现动物缺氧(10%O_2)10min后,平均肺动脉压(mPAP)和肺血管阻力(PVR)较基础值明显升高(P<0.01):而缺氧同时吸入40ppmNO10min,mPAP和PVR较缺氧时明显降低(P<0.01),与基础值无显著差别(P>0.05),且发现△PVR%为2.94±9.85%,较缺氧时66.18±23.39%明显降低(P<0.01),但吸入NO对体动脉压、体血管阻力,心输出量、血气和高铁血红蛋白无明显影响。从而提示吸入NO选择性降低缺氧性肺动脉高压且完全逆转HPV。 相似文献
992.
TREATMENTOFFULMINANTLIVERFAILUREWISTARRATSWITHIMPLANTEDARTIFICIALCELLSMICROENCAPSULATEDLIVINGHEPATOCYTESSongJichang,LiTao,XuJ... 相似文献
993.
de Ru MH Gille JJ Nieuwint AW Bijlsma JB van der Blij JF van Hagen JM 《American journal of medical genetics. Part A》2005,137(1):81-87
We present a boy with blepharophimosis, ptosis, epicanthus inversus, microcephaly, mild mental retardation, and growth delay. Chromosomal analysis revealed a male karyotype with an interstitial deletion in the long arm of chromosome 3. DNA-analysis showed that the deletion is of maternal origin and encompasses the region between markers D3S1535 and D3S1593. The deletion contains not only the FOXL2 gene, but also the gene encoding ataxia-telangiectasia and Rad3-related protein (ATR). Mutations in FOXL2 have been shown to cause blepharophimosis-ptosis-epicanthus inversus syndrome (BPES). ATR has been identified as a candidate gene for Seckel syndrome, an autosomal recessive syndrome that comprises growth retardation, microcephaly, and mental retardation. We hypothesize that our patient has a contiguous gene syndrome and that the non-BPES-associated abnormalities (microcephaly, mild mental retardation, and growth delay) are the result of the deletion of the maternal ATR gene. However, it has not yet been excluded that haploinsufficiency of some other gene in this region plays a role. 相似文献
994.
Qian KX Zeng P Ru WM Yuan HY 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(5):562-564
For long-term application, rotary pumps have to solve the problems of bearing wear and thrombosis along the bearing. Some investigators choose the magnetic bearing for zero friction and to provide no contact between the rotor and stator; the former avoids the mechanical wear and the latter eliminates the possibility of thrombus formation. The authors have tried and have found, however, that it is difficult to apply a magnetic bearing to the rotary pump without disturbing its simplicity, reliability, and implantability, and have therefore developed a much simpler approach to achieve the same results. Instead of using a sliding bearing, a rolling bearing has been devised, and its friction is about 1/15 that of the sliding bearing. Furthermore, a wearproof material of ultra high molecular weight polythene has been adopted to make the rollers, and its antiwear property is eight times better than metal. The service life of the bearing has thus been prolonged. To prevent thrombus formation along the bearing, the impeller reciprocates axially as the impeller changes its rotating speed periodically to produce a pulsatile flow. The reciprocation is the result of the effects of a magnetic force between the motor rotor and stator and a hydraulic force between the blood flow and the impeller. Similar to a piston pump, the oscillating impeller can make the blood flow in and out of the bearing, resulting in washout with fresh blood once a cycle. This obviously helps to prevent thrombosis along the bearing and in the pump. Endurance tests with saline of this novel pump demonstrated device durability, promising long-term assisted circulation. 相似文献
995.
A preduodenal position of the portal vein (PDPV) is a very rare congenital anomaly; even rarer is its association with a preduodenal position of the common bile duct (PDCBD). To the seven cases of PDCBD mentioned in the literature, we add this particularly rare case which is associated with multiple abnormalities such as situs inversus totalis, intestinal malrotation, short pancreas, bilobed spleen, accessory spleen, and abnormal ramification of the celiac axis, superior mesenteric artery and renal arteries. Besides describing and illustrating this case, we also discuss the anatomy and embryology of these structures and briefly review the patterns of previously reported cases that we found. We performed an immunohistochemical examination of the pancreas to demonstrate the ventro-dorsal pancreas in our case. For the explanation of the embryology of the PDCBD, the ventro-dorsal pancreas and PDPV malformation, we emphasized the reverse rotation of the ventral pancreas and duodenum. 相似文献
996.
Streamlined design of impeller and its effect on pump haemolysis 总被引:1,自引:0,他引:1
To investigate the effect of impeller design on pump haemolysis, five impellers with different numbers of vanes or different vane angles were manufactured and tested in one pump for haemolysis comparison. The impellers had the same dimension and logarithmic spiral vane form that coincided with the stream surfaces in the pump, according to an analytical and three-dimensional design method developed by the authors. Consequently, an impeller with six vanes and a 30 degrees vane angle had the lowest haemolysis index. The result agrees with the theoretical analyses of other investigators searching for the optimal vane number and vane angle to achieve the highest efficiency of the pump. 相似文献
997.
Methods for genetic risk prediction have been widely investigated in recent years. However, most available training data involves European samples, and it is currently unclear how to accurately predict disease risk in other populations. Previous studies have used either training data from European samples in large sample size or training data from the target population in small sample size, but not both. Here, we introduce a multiethnic polygenic risk score that combines training data from European samples and training data from the target population. We applied this approach to predict type 2 diabetes (T2D) in a Latino cohort using both publicly available European summary statistics in large sample size (Neff = 40k) and Latino training data in small sample size (Neff = 8k). Here, we attained a >70% relative improvement in prediction accuracy (from R2 = 0.027 to 0.047) compared to methods that use only one source of training data, consistent with large relative improvements in simulations. We observed a systematically lower load of T2D risk alleles in Latino individuals with more European ancestry, which could be explained by polygenic selection in ancestral European and/or Native American populations. We predict T2D in a South Asian UK Biobank cohort using European (Neff = 40k) and South Asian (Neff = 16k) training data and attained a >70% relative improvement in prediction accuracy, and application to predict height in an African UK Biobank cohort using European (N = 113k) and African (N = 2k) training data attained a 30% relative improvement. Our work reduces the gap in polygenic risk prediction accuracy between European and non‐European target populations. 相似文献
998.
目的:观察黄连解毒汤治疗热毒型脓毒症的临床疗效。方法:选择热毒型脓毒症患者115例,随机分为两组,对照组给予常规治疗,观察组在常规治疗基础上加用黄连解毒汤加减治疗,7 d为1个疗程,分别于治疗前、治疗后第3天、第7天进行中医证侯积分评定,同时采用急性生理及慢性健康评分Ⅱ、器官功能障碍评分对两组患者病情进行评分,记录体温、心率变化,检测白细胞总数、中性粒细胞总数、C反应蛋白、降钙素原、白细胞介素-6、肿瘤坏死因子-α、空腹血糖指标。结果:观察组的临床疗效明显优于对照组,观察组的中医证侯积分下降优于对照组,差异均有统计学意义(P0.05)。两组急性生理及慢性健康评分Ⅱ、器官功能障碍评分、体温、心率、白细胞总数、中性粒细胞总数、C反应蛋白、降钙素原、白细胞介素-6、肿瘤坏死因子-α、空腹血糖均较治疗前显著下降(P0.05),且观察组相关指标的降低明显优于对照组,差异具有统计学意义(P0.05)。两组在安全性评价方面无显著性差异,治疗方案均是安全可行的。结论:黄连解毒汤加减治疗热毒型脓毒症具有确切的临床疗效,能明显改善脓毒症患者的炎症因子水平,同时更加有利于血糖的控制。 相似文献
999.
帕金森精神病(Parkinson’s disease psychosis,PDP)是帕金森病(Parkinson’s disease,PD)晚期患者出现的一种精神病性障碍,PDP的认知和治疗对帕金森病患者十分重要。然而目前对PDP明确的治疗方式尚处于探索和研究状态,寻找合适的治疗药物是PDP研究的热门领域之一。本文综述PDP与PD之间的关系、区别及其诊断标准,围绕PDP现有的临床治疗药物以及处于临床试验阶段的新药研究,详细介绍了PDP的研究与治疗进展。 相似文献
1000.
目的 分析类风湿关节炎(rheumatoid arthritis, RA)患者的风湿病家族史特征及其临床意义。方法 采用现场问卷调查方法,共调查890例RA患者,其中资料完整者803例,内容包括患者的性别、年龄、吸烟史、饮酒史、身高、体重、风湿病家族史、临床及血清学特征、疼痛和疾病总体评价、多维健康评估问卷等,并根据RA患者有无家族史进行分组比较。结果 本研究中,RA患者发病年龄为(45.09 ±14.50)岁,男女比例1 ∶3.5。有风湿病(包括RA、脊柱关节炎、干燥综合征、系统性红斑狼疮、系统性硬化症)家族史的患者123例(123/803, 15.32%), 其中一级亲属患病者占有家族史者73.98%(91/123),二级亲属患病者占有家族史者17.89%(22/123),一级+二级亲属均患病10例(8.13%)。家族史疾病种类以RA为主,为70.73%(87/123),其他风湿性疾病为21.95%(27/123),RA合并其他风湿病占7.32%(9/123)。根据有无家族史,对两组RA患者的人口学特征和临床指标进行比较,结果显示:在有家族史患者中,发病年龄提前6.04年[(39.97±13.68)岁 vs.(46.01 ±14.46)岁],类风湿因子阳性率高(78.48% vs. 66.67%), 差异具有统计学意义(P<0.05)。校正性别、体重指数及抗环瓜氨酸肽抗体等混杂因素后,有家族史患者的发病年龄提前4.54年(β = -4.54;95%CI:-8.70, -0.38;P < 0.05)。进一步分层分析发现,在吸烟RA患者中,有家族史者发病年龄提前10.02年,差异具有统计学意义(β = -10.02;95%CI:-17.60, -2.43;P = 0.01);而在不吸烟RA患者中,有家族史者发病年龄提前3.27年,差异无统计学意义(β = -3.27;95%CI:-8.37, 1.82;P= 0.21)。结论 风湿病家族史是RA发病提前的危险因素,与吸烟可能具有协同作用。 相似文献