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81.
本研究运用荧光金(FG)逆行束路追踪与5-HT1A受体免疫荧光组织化学染色技术相结合,观察了大鼠腰骶髓后连合核(DCN)和中间带外侧核(IML)内感受盆腔内脏伤害性信息并向外侧臂旁核(LPB)发出投射的神经元呈5-HT1A受体免疫反应阳性。将FG注入一侧LPB后,可在腰骶节段(L6-S2)观察到大量的FG逆标神经元,这些FG逆标神经元主要集中于DCN和IML内,以同侧为主;5%福尔马林注入大鼠结肠后,Fos蛋白阳性神经元主要分布于腰骶髓DCN和IML,以同侧为主,在同侧脊髓背角I层、II层和深层也有少量的分布。另外,在腰骶髓DCN和IML内,还可观察到大量5-HT1A受体阳性的神经元胞体、纤维和终末,同时有部分Fos蛋白阳性的FG逆标神经元呈5-HT1A受体阳性。上述结果提示,大鼠腰骶髓DCN和IML内的5-HT能终末可能对盆腔内脏伤害性信息的传递发挥调控作用。  相似文献   
82.
We studied the clinicopathologic, immunophenotypic, and cytogenetic features of 26 patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) associated with serum IgM paraprotein. The study group (16 men; 10 women; median age, 64 years; range, 40-82 years) represents approximately 2.5% of CLL/SLL cases at our institution. The paraprotein level ranged from 1 to 14 g/L (median, 4 g/L). Neoplasms in bone marrow were composed of small round lymphocytes arranged in nodular (n = 6), diffuse (n = 5), interstitial (n = 5), or mixed (n = 10) patterns. All cases were positive for monotypic surface immunoglobulin light chain, IgM/IgD, CD5, CD19, CD20, and CD23. CD11c (14/20 [70%]), CD79b (11/19 [58%]), FMC-7 (11/26 [42%]), CD22 (8/20 [40%]), and ZAP-70 (6/19 [32%]) were expressed in subsets of cases. Of 17 bone marrow specimens assessed by conventional cytogenetics, 6 were abnormal and 11 were diploid. The overall survival of this group (median follow-up, 24 months) was not significantly different from that for an age-, sex-and stage-matched group of 52 CLL/SLL patients without IgM paraprotein (P = .60). We conclude that CLL/SLL cases with serum IgM paraprotein are similar to other CLL/SLL cases in their clinicopathologic and immunophenotypic features.  相似文献   
83.
84.
介绍了“四川联大Ⅰ型”(以下简称:SUUⅠ)管外流式(ELF)中空纤维膜式氧合器的研制、设计、外形制做及离心封端等过程,重点介绍了中空纤维膜材料选择,膜肺离心封端的原理、材料、设备及方法,并对聚氨酯胶进行离心封端的具体步聚作了较详细的叙述。作者根据自身在国外与国内的研制经验,认为离心封端的关键在于:(1)中空纤维膜材料的质量及成束质量;(2)聚氨酯封端胶材料固化特性的掌握及料量计算;(3)反应温度控制;(4)气体排除;(5)转速的控制;(6)纤维束的安装;(7)脱模和切头的时间掌握等方面。作者用外购的材料和自己设计制造的离心封端机成功地制造了我国第一个管外流式(ELF)中空纤维成人氧合器。SUUⅠ膜式氧合器的设计是作者在国外建立的交叉流式膜肺O2、CO2传递模型的具体应用。  相似文献   
85.
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   
86.
企业员工应对方式与心理健康之间的关系   总被引:3,自引:2,他引:3  
目的:验证不同应对方式对心理健康的单独与共同影响。方法:对4745名被试用分层回归的方法分析不同应对方式对心理健康的单独影响和交互作用。结论:单独使用“消极应对”的应对方式,对心理健康水平存在不利影响;而单独使用“积极应对”的应对方式能在一定程度上改善心理健康水平。“消极应对”与“积极应对”两种应对方式结合使用能显著改善心理健康水平,比单独使用这两种应对方式对心理健康更有利。  相似文献   
87.
Angiomyolipoma (AML) is the most common benign mesenchymal tumor of the kidney. It belongs to the family of perivascular epithelioid cell tumors and is typically composed of blood vessels, adipose tissue, and smooth muscle- like cells, which are characteristically positive for HMB-45. Results of recent studies suggest that p53 mutation may play an important role in AML progression. Here, we describe a locally destructive renal AML in a patient with tuberous sclerosis. The tumor consisted of mostly epithelioid cells with marked nuclear pleomorphism and frequent mitoses and was positive for HMB-45. The diagnosis of atypical epithelioid AML was made. Codon alteration in the p53 gene was not detected, despite focal p53 immunoreactivity and single nucleotide polymorphism at exon 6. Our finding indicates no definite link between p53 abnormalities and the atypical appearance of AML. To the best of our knowledge, this is the second renal AML case investigated for p53 mutations.  相似文献   
88.
目的 研究病毒载量检测和CD4^ 计数在评价人类免疫缺陷病毒(HIV)感染者疗效中的应用效果。方法 对HIV感染者临床病例73例进行了实验室和临床观察,其中包括6例鸡尾酒治疗病例、36例中药试验性治疗病例及31例未进行治疗的感染者。主要实验室指标包括血浆病毒载量及T淋巴细胞亚群计数。结果 在进行治疗后3个月时联合治疗组的病毒载量明显低于其他两组,并且在其后保持在很低的水平,CD4^ 计数水平明显高于其他两组并在其后持续升高。在整个观察期间,中药治疗组的病毒载量检测和CD4^ 计数水平与未治疗组差异无显著性,但在临床症状观察中中药治疗组较未治疗组有明显改善。结论 病毒载量检测和CD4^ 计数试验是评价抗HIV治疗疗效的有效方法。  相似文献   
89.
研制出一台采用永磁轴承的左心室辅助装置(LVAD)。该装置包括一个定子和一个转子,采用径向驱动方式;转子包括驱动磁钢和叶轮,电机定子线圈和泵壳组成定子。装置设计采用了一种特殊结构的永磁轴承。转子的位置测量表明,转子稳定悬浮的前提条件是必须有较高的转速(大于3250r/min)且流量大于1L/min。用猪血为介质所做的液动力测试表明,当转速达到3500r/min~4000r/min时,血泵输出流量达到4L/min~6L/min,输出压力达到100mmHg。该装置重200g,最大处直径为40mm。  相似文献   
90.
Our former work demonstrated that our impeller pump could support the circulation of experimental animals for several months without harm to blood elements or organ function. The termination of the experiments was mostly related to wear of the mechanical bearing and thrombosis along the bearing. To solve the bearing problem, we investigated a magnetic bearing in our lab, which resulted in some new problems, such as complicated design and control, considerable energy consumption, and lesser reliability. Progress in developing an impeller pump for long-term application has recently been achieved. Instead of using a sliding bearing system, we devised a rolling bearing system. Its service life is more than 10 years because of a wearproof roller made of ultra high molecular weight polythene. To avoid thrombus formation, we introduced a special purge system to the bearing, allowing the saline with heparin to be infused through the bearing into the pump. The bearing, therefore, keeps working in the saline, and no thrombus will be formed. Animal experiments demonstrated that a 30 ml fluid infusion per hour is enough to prevent thrombus formation. With these improvements, the impeller pump has continuously run for 8 months, and no bearing wear can be measured. The device, weighing 150 g, is fully implantable, consumes approximately 9.6 watts, and delivers a 9L/min blood flow against a 120 mm Hg mean pressure and reaches a highest total efficiency of 24.7% for the motor (including the controller) and pump. The system can produce both pulsatile and nonpulsatile flow according to requirements.  相似文献   
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