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71.
目的:探究11β-羟化类固醇脱氢酶1(11β-hydroxysteroid dehydrogenase,11β-HSD1)基因敲除对小鼠整体代谢和认知功能的影响。方法:将C57BL/6J为遗传背景的野生对照组及11β-HSD1基因敲除组各15只小鼠高脂喂养20周,代谢笼评估能量代谢,行为学评估观察小鼠认知功能,电镜评估海马体的线粒体结构,免疫荧光及PCR确定其认知功能、线粒体功能相关基因及炎症基因的变化。结果:11β-HSD1基因敲除能够提高高脂喂养小鼠学习和记忆能力,改善握力,改善海马体的微结构、线粒体含量变多,认知相关基因、线粒体呼吸功能相关基因上调,炎症相关基因改变。结论:11β-HSD1敲除后高脂饮食喂养小鼠认知功能显著改善,握力显著提高,可能是治疗认知功能障碍的有效靶点。 相似文献
72.
Coagulation factor replacement can effectively treat or prevent most hemophilia complications, but it is expensive. Although published data describe how to achieve therapeutic goals through cost-effective selection and dosing of replacement products, criteria are not universally known or followed. A review of our institution's experience revealed overdosing of coagulation factors in the majority of patients treated during a 12-month period, at a cost that approached $700,000. Consequently, we established mandatory clinical pathology consultation before releasing such factors. In the subsequent 30 months, 32 adults received 64 courses of treatment. For patients with hemophilia A, the mean cost per admission was reduced by approximately 27% (total savings, $61,536). For patients with factor VIII inhibitor, there was an approximate 6% cost reduction (total savings, $47,292). The combined savings was $108,828. The mean plasma factor level achieved during the intervention period was 84% +/- 55% compared with 117% +/- 58% for the preintervention period (P = .008). Neither the number of treatment (factor transfusion) days nor the number of RBC transfusions changed significantly. Our data support that pathology consultation yields consistent and appropriate therapy and improves resource utilization. 相似文献
73.
目的探讨产科多器功能障碍综合征(MODS)的诱因、临床诊断及处理。方法对16例MODS的临床资料进行回顾性分析。结果导致MODS的主要因素为妊娠期高血压疾病及产后出血,器官功能障碍以肾功能衰竭为最多见。结论及时处理MODS的诱发因素,积极治疗妊娠期高血压疾病及产后出血,早期诊断及治疗肾功能衰竭及凝血功能障碍,是减少产科MODS患者死亡的关键。 相似文献
74.
磁刺激用平面线圈结构的优化研究 总被引:2,自引:0,他引:2
文中建立了采用任意形状平面线圈磁刺激仪的RLC模型,给出了模型参数的计算方法。为了优化线圈,将磁刺激仪线圈的性能指标分为反映线圈输出性能的峰值磁能和反映线圈结构的几何变量。在磁刺激激活函数达到阈值条件下,调整平面螺旋线圈的结构并计算出依赖于线圈结构参数的输出性能值,从而,寻找最优的线圈几何参数。优化结果表明:线圈外半径是关键因素,给定阈值条件,选择合适的线圈外半径,可以大大降低线圈峰值磁能;另外,现在使用的圆环线圈并非最优,D形线圈优于圆环线圈。 相似文献
75.
企业员工应激源的因素结构研究 总被引:8,自引:1,他引:8
目的 :该研究旨在确立企业员工应激源的因素结构。方法 :经过对 394 6名被试的探索性因素分析 ,提出企业员工应激源的 9因素结构。结果 :因素分别命名为职业发展、住房问题、工作特征、社会环境、人际关系、经济收入、子女问题、组织气氛和夫妻关系。结论 :企业员工应激源的 9因素结构获得了验证性因素分析的支持。 相似文献
76.
Pituitary Adenylate-Cyclase-Activating Polypeptide (PACAP) Binding Sites and PACAP/Vasoactive Intestinal Polypeptide Receptor Expression in Human Pituitary Adenomas 下载免费PDF全文
77.
Long Jin Jiangyue Song William F. Chandler Barry G. England James B. Smart Ariel Barkan Ricardo V. Lloyd 《Endocrine pathology》1990,1(1):25-36
The effects of the hypothalamic hormones, thyrotropin-releasing hormone (TRH), and somatostatin (SRIH), and of phorbol 12-myristate
13-acetate (PMA) on PRL and GH secretion and messenger RNA (mRNA) levels were analyzed in 10 GH and/or PRL producing adenomas
after culturing the tumor cells in the presence of these secretagogues for 7 days. The expression of chromogranin A and B
mRNAs was also examined. All four of the clinically diagnosed GH adenomas expressed or secreted both GH and PRL while four
of six clinically diagnosed prolactinomas produced or secreted both PRL and GH. Prolactinomas had less than 10% of tumor cells
expressing chromogranin A mRNA while more than 40% of the adenoma cells expressed chromogranin B mRNA. TRH stimulated PRL
secretion and increased PRL mRNA levels while SRIH decreased GH secretion and mRNA expression in some cases. Unexpectedly,
PMA stimulated PRL mRNA levels four- to sevenfold above control levels in two adenomas and generally stimulated chromogranin
A and B mRNA expression but not GH mRNA, as determined by Northern hybridization and in situ hybridization analyses.
These results indicate that cultured prolactinoma cells express significantly more chromogranin B mRNA than chromogranin A
mRNA, and that PMA increases PRL mRNA expression in some prolactinomas, although the effect of PMA on various adenomas reflects
the heterogeneity of these tumors with respect to protein kinase C stimulation. 相似文献
78.
采用纱球进行口腔护理的效果观察 总被引:5,自引:0,他引:5
目的探寻有效的口腔护理方法,取得更好的清洁口腔及洁牙效果。方法随机对53例有口腔护理适应症、意识清醒的患者,用纱球或棉球分别作左或右侧牙齿及口腔粘膜的清洁护理,并按同一标准进行效果评价。结果53例患者,以纱球擦洗侧,效果好的为42例,一般为11例,差为0例。以棉球擦洗侧,效果好为13例,效果一般为40例,差为0例,两组效果比较有显著性差异(P<0.01)。结论以纱球作口腔护理的清洁效果明显优于棉球的清洁效果。 相似文献
79.
Retroposed new genes out of the X in Drosophila 总被引:12,自引:0,他引:12
New genes that originated by various molecular mechanisms are an essential component in understanding the evolution of genetic systems. We investigated the pattern of origin of the genes created by retroposition in Drosophila. We surveyed the whole Drosophila melanogaster genome for such new retrogenes and experimentally analyzed their functionality and evolutionary process. These retrogenes, functional as revealed by the analysis of expression, substitution, and population genetics, show a surprisingly asymmetric pattern in their origin. There is a significant excess of retrogenes that originate from the X chromosome and retropose to autosomes; new genes retroposed from autosomes are scarce. Further, we found that most of these X-derived autosomal retrogenes had evolved a testis expression pattern. These observations may be explained by natural selection favoring those new retrogenes that moved to autosomes and avoided the spermatogenesis X inactivation, and suggest the important role of genome position for the origin of new genes. 相似文献
80.
Long A Tremblay L Richard L Lemieux R Goldman M 《Immunohematology / American Red Cross》2002,18(4):120-122
Low concentrations of sodium hypochlorite (chlorine bleach) are known to destroy S antigen on intact fresh red blood cells (RBCs). Sodium hypochlorite is commonly used as a disinfectant. We report nondetection of the S antigen in tube and microplate saline indirect antiglobulin testing (SIAT) with a lot of commercial saline utilized in our donor screening and reference laboratories. Known S+s+ RBCs were found to be nonreactive with anti-S by SIAT in our reference laboratory. Our investigation demonstrated the presence of chlorine in the commercial saline. The saline lot was used for several days of donor screening and recall of FFP and platelet concentrates was initiated. Two lots of saline were recalled from blood banks across North America. 相似文献