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81.
笔者观察了大鼠失血性休克(HS)对内毒素诱导肿瘤坏死因子α(TNFα)产生的影响及其细胞来源,并结合休克后组织内脂多糖结合蛋白(LBP)mRNA的表达变化,对其分子机制进行了初步分析。研究结果显示,静脉注射LPS后90min,HS+LPS组血浆TNFα水平分别较HS组高20倍(P<0.01),LPS组高2.7倍(P<0.05);休克和复苏后,外周血白细胞产生TNFα的能力明显受抑,而肝Kupfer's细胞产生TNFα的能力却明显增强;休克后不仅肝组织内LBPmRNA表达增多,肺、肾组织内LBPmRNA也相继表达增加。研究结果提示,失血性休克能显著增敏内毒素诱导TNFα的产生作用,其机制可能与休克后组织内LBP表达上调有关,组织巨噬细胞群(如Kupfer细胞)可能是休克后细胞因子产生的主要来源。  相似文献   
82.
壳聚糖醋酸溶液对凝血作用的研究   总被引:1,自引:0,他引:1  
研究了不同脱乙酰度和不同分子量壳聚糖醋酸溶液的凝血作用。发现壳聚糖醋酸溶液使抗凝血液中红细胞发生了明显的聚集和变形。通过不同分子量和脱乙酰度壳聚糖的促红细胞聚集实验,证明了低脱乙酰度壳聚糖(60%~70%)使红细胞聚集效果更好,分子量在105~106范围内作用不十分明显。对血液的凝血酶时间(TT)、凝血酶原时间(PT)、活化部分促凝血酶原激酶时间(APTT)和纤维蛋白原浓度(FIB)的测定结果验证了壳聚糖醋酸溶液凝血机理不依赖于血小板和常规“瀑布”凝血机制。  相似文献   
83.
Osteoporosis and obesity are two severe complex diseases threatening public health worldwide. Both diseases are under strong genetic determinants as well as genetically correlated. Aiming to identify pleiotropic genes underlying obesity and osteoporosis, we performed a bivariate genome-wide association (GWA) meta-analysis of hip bone mineral density (BMD) and total body fat mass (TBFM) in 12,981 participants from seven samples, and followed by in silico replication in the UK biobank (UKB) cohort sample (N = 217,822). Combining the results from discovery meta-analysis and replication sample, we identified one novel locus, 17q21.31 (lead SNP rs12150327, NC_000017.11:g.44956910G > A, discovery bivariate P = 4.83 × 109, replication P = 5.75 × 105) at the genome-wide significance level (ɑ = 5.0 × 10−8), which may have pleiotropic effects to both hip BMD and TBFM. Functional annotations highlighted several candidate genes, including KIF18B, C1QL1, and PRPF19 that may exert pleiotropic effects to the development of both body mass and bone mass. Our findings can improve our understanding of the etiology of osteoporosis and obesity, as well as shed light on potential new therapies.Subject terms: Genome-wide association studies, Gene expression profiling  相似文献   
84.
Tian G  Zhang S  Li Y  Bu Z  Liu P  Zhou J  Li C  Shi J  Yu K  Chen H 《Virology》2005,341(1):153-162
We generated a high-growth H5N1/PR8 virus by plasmid-based reverse genetics. The virulence associated multiple basic amino acids of the HA gene were removed, and the resulting virus is attenuated for chickens and chicken eggs. A formalin-inactivated oil-emulsion vaccine was prepared from this virus. When SPF chickens were inoculated with 0.3 ml of the vaccine, the hemagglutinin-inhibition (HI) antibody became detectable at 1 week post-vaccination (p.v.) and reached a peak of 10log2 at 6 weeks p.v. then slowly declined to 4log2 at 43 weeks p.v. Challenge studies performed at 2, 3 and 43 weeks p.v. indicated that all of the chickens were completely protected from disease signs and death. Ducks and geese were completely protected from highly pathogenic H5N1 virus challenge 3 weeks p.v. The duration of protective immunity in ducks and geese was investigated by detecting the HI antibody of the field vaccinated birds, and the results indicated that 3 doses of the vaccine inoculation in geese could induce a 34 weeks protection, while 2 doses induced more than 52 weeks protection in ducks. We first reported that an oil-emulsion inactivated vaccine derived from a high-growth H5N1 vaccine induced approximately 10 months of protective immunity in chickens and demonstrated that the oil-emulsion inactivated avian influenza vaccine is immunogenic for geese and ducks. These results provide useful information for the application of vaccines to the control of H5N1 avian influenza in poultry, including chickens and domestic waterfowl.  相似文献   
85.
We examined the role of dorsal respiratory group (DRG) inspiratory neurons as transmitters of respiratory drive to phrenic and intercostal motoneurons and as relays of afferent information to ventral respiratory group (VRG) bulbospinal, inspiratory neurons. Attempts to antidromically activate 76 DRG neurons from the spinal cord at the C7 segment resulted in only 4 (5.3%) successes (3 contralateral, 1 ipsilateral). Cross-correlating DRG neuron discharge with that of the ipsilateral (56) and contralateral (20) phrenic nerve detected common activation peaks in 2 and 3 cases respectively, with no evidence for monosynaptic connections. Cross-correlating DRG neuron discharge with that of bulbospinal, inspiratory VRG neurons found some evidence for interaction. Peaks in 7 of 73 (10%) cross-correlation histograms were attributed to a monosynaptic excitation of DRG neurons by VRG neurons, although a common activation cannot be ruled out; troughs, some with an accompanying peak, in 9 (12.3%) histograms were interpreted as a combined excitation of the DRG neuron and delayed inhibition of the VRG neuron. In addition, 2 cross-correlation histograms showed peaks with latencies and half-amplitude widths consistent with a disynaptic excitation of a DRG neuron by a bulbospinal inspiratory VRG neuron. Cross-correlating the discharge of 57 pairs of DRG inspiratory neurons (6 contralateral) detected common activation peaks in 7 (12.3%) cases (none contralateral) and one case interpreted as evidence for a disynaptic excitation. These findings suggest that the role of the DRG inspiratory neurons in rats differs from that in cats, primarily because they do not act to transmit respiratory rhythmic drive directly to phrenic and intercostal motoneurons. The results offer some support for an excitation of DRG neurons by VRG inspiratory neurons, but no support for a role of DRG inspiratory neurons as mediators of afferent information transfer to VRG bulbospinal inspiratory neurons.  相似文献   
86.
87.
研究长期慢性轻度脑外伤对大鼠脑线粒体功能的影响。大鼠连续1、5、10、15、20、25、30d轻度闭合性颅脑撞击后分离脑线粒体,测定线粒体肿胀度、膜流动性、膜磷脂含量、呼吸功能、线粒体呼吸酶、超氧化物歧化酶(SOD)、丙二醛(MDA)和Ca2 等指标以显示线粒体功能、抗氧化能力的变化。结果显示,第15、20、25、30d大鼠脑线粒体明显肿胀,膜磷脂降解,膜流动性下降,呼吸功能衰减,呼吸酶、SOD活性降低,Ca2 、MDA含量升高。由此认为,经常性头部撞击可造成大鼠脑线粒体功能受损,其机制可能与脑线粒体膜损伤后继发的自由基生成增加、脑线粒体能量代谢障碍有关。  相似文献   
88.
The impact of the insertion (I)/deletion (D) (I/D) polymorphism in the angiotensin 1-converting enzyme (ACE) gene on the extent of white matter myelin loss (ML) was investigated in four regions of the cerebral cortex in an autopsy-confirmed series of 93 patients with Alzheimer's disease (AD). The possible influence of APO E epsilon4 allele acting in concert with ACE D allele was assessed. The extent of ML did not differ between D/D, I/D and I/I genotype groups when data from all four brain regions were combined. However, separate analysis showed that the frontal and temporal cortex tended to be affected more severely by ML in patients with D/D genotype compared to those with I/D and I/I genotypes. Stratification according to APO E epsilon4 allele revealed a greater overall ML in patients bearing at least one copy of ACE D allele and one APO E epsilon4 allele, especially in individuals homozygous for both. The APO E epsilon4 allele may therefore act synergistically in patients with AD (and other subjects) bearing ACE D/D genotype to increase the risk of ML, perhaps through transient ischaemic episodes consequent upon poor cardiac output associated with coronary atherosclerosis in patients with the APO E epsilon4 allele.  相似文献   
89.
脾LAK细胞培养上清有前后两个杀伤活性高峰,以第11d为界,第一个活性高峰与上清中BLT酯酶活性呈正相关。含血清和无血清的培养体系产生BLT酯酶的机理可能不同。在有高活性rIL-2时,BLT酯酶的分泌与无血清培养液中有无2-ME相关。  相似文献   
90.
在目前不能直接观测病人内部器官微循环改变的条件下,应用模糊聚类的理论和方法,对主要常见病有意义的的甲襞微循环改变进行聚类,同时参考国内外相关文献的结果,提出了主要常见病有意义的甲襞微循环改变群。在改变群中任意提出3、4、5、6、7、8项改变指标,形成改变组合,一种组合重复出现二次以上的重复率,随组合改变指标数的增多而减少(70.36%~4.36%)。将改变群分成重要指标和参考指标二类,从每类中提出三项形成组合,重复率仅为0.34%。说明组合方式的影响十分巨大。经过反复探索、大量实践,有可能找出对疾病的符合率较高、漏诊率较低、误诊率较小的最佳组合方式。  相似文献   
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