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81.
The case is described of a 40 year old man with delusions and hallucinations, who at the start of this study was taking doses of neuroleptic medication greatly in excess of those that have been demonstrated to be optimally effective. Over 48 weeks, using PQ methods and detailed interviewing, his progress was charted as the medication was reduced to more appropriate levels. Across this change, his delusional beliefs remained unchanged, but there were substantial reductions in auditory hallucinations, as well as in hopelessness and anxiety. The case has implications for concepts of therapy in the psychoses and for the methodology of therapy studies. It also illustrates possible benefits of using PQ or other self-assessment methods as a means of calibrating therapy and perhaps enhancing compliance. © 1998 John Wiley & Sons, Ltd. 相似文献
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Over the past 100 years Drosophila has been developed into an outstanding model system for the study of evolutionary processes. A fascinating aspect of evolution
is the differentiation of sex chromosomes. Organisms with highly differentiated sex chromosomes, such as the mammalian X and
Y, must compensate for the imbalance in gene dosage that this creates. The need to adjust the expression of sex-linked genes
is a potent force driving the rise of regulatory mechanisms that act on an entire chromosome. This review will contrast the
process of dosage compensation in Drosophila with the divergent strategies adopted by other model organisms. While the machinery of sex chromosome compensation is different
in each instance, all share the ability to direct chromatin modifications to an entire chromosome. This review will also explore
the idea that chromosome-targeting systems are sometimes adapted for other purposes. This appears the likely source of a chromosome-wide
targeting system displayed by the Drosophila fourth chromosome. 相似文献
84.
目的研究比较不同浓度、剂量,等比重布比卡因对产妇的麻醉效果及新生儿的影响,为临床麻醉提供参考依据。方法选择ASAⅠ~Ⅱ级初次足月妊娠拟择期剖宫产手术孕妇80例,随机分为A、B二组,每组各40例。均在左侧卧位下行腰-硬联合穿刺,L2-3进针,见脑脊液外流后,针斜面向下注入等比重布比卡因:A组:8mg(0·5%,1·6ml;配法:0·75%布比卡因2ml+脑脊液1ml);B组:9·6mg(0·6%,1·6ml;配法:0·75%布比卡因2ml+脑脊液0·5ml),20s注药完毕。记录麻醉前(基础值)和脊麻注药后1、3、5、7、10、15min各时间点的平均动脉压(MAP)、心率(HR)、脉搏血氧饱合度(SpO2)。测定并记录麻醉起效时间、平面固定时间、最高麻醉平面点(胸,T)、麻醉完全消退时间、下肢阻滞的最大程度、麻醉并发症等。结果A组感觉阻滞起效时间长于B组(69·27±21·48vs52·43±27·61s,P<0·05);两组最高阻滞平面(T4·50±1·44vsT4·10±0·57)及最高阻滞平面的固定时间(7·69±1·36vs7·35±1·22min)相似(P>0·05)。A组麻醉完全消退时间快于B组(218·40±18·57vs256·22±16·72min,P<0·05);Bromage评分A组明显小于B组(2·03±0·68vs2·93±0·21,P<0·05);麻醉后B组低血压发生率明显高于A组(P<0·05)。两组病人的麻醉效果均优,肌松满意。所有新生儿的Apgar评分均在7分以上,无组间差异。结论两组病人均产生了良好的脊麻效果,权衡利弊剖宫产脊麻时应用8mg(0·5%,1·6ml)布比卡因更为安全合理。 相似文献
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刘秀珍 《生物医学工程学杂志》2007,24(6):1256-1259
为提高诊断X线机的诊断质量,促进放射防护工作的开展,根据"国际辐射单位和测量委员会"(International Commission on Radiological Units and Measurements,ICRU),"国际放射防护委员会"(International Commission on Radiation Protection,ICRP)关于辐射对人体的损害之划分标准,作者对岛津制作所90年代中期生产的XEB150L-20型500mA X线机按照国家规定的要求及有关标准,分别对辐射空气释动能率,半价层,输入量重复性,输出量线性,高对比分辨率,光野与照射野一致性及X线管的焦点等参数进行了测试。分析了测试的数据与结果,并进行了简要的评价。 相似文献
87.
Ali Gunes Author Vitae Yusuf Ozturk Author Vitae Author Vitae 《Computers in biology and medicine》2009,39(7):590-594
We developed a database compiling in vivo doses of compounds for various activities in certain animal species. The related database covers almost 100 years of experiments. The conceptual scheme of the database was created using concepts of the entity-relationship modeling principles. Using published references, dosages and their effects on laboratory animals were entered as data. As the next stage of our work, we have started to examine the available literature to information about the experimental dosages of various drugs used in other studies.The database provides various interfaces, including graphical-user interfaces and interfaces for Internet access. The database will be useful as a knowledge infrastructure for researchers who have to perform dose-scan experiments for a specific pharmacological activity. The basic benefit of that knowledge infrastructure is that it will enable virtual pharmacological experiments that will be considerably less expensive than conventional laboratory experiments, because the number of animals used and the number of dose-scan experiments will be greatly reduced. The developed database will also be helpful for new drug development studies and for responding to queries about animal types, drugs used, drug interactions, and results. 相似文献
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Recent genome‐wide association studies identified the common genetic variants in 9p21 were associated with the coronary artery disease (CAD). However, whether this locus could predict the severity of CAD in Chinese Han population is unclear. 499 CAD patients who underwent coronary angiography (CAG) have been enrolled for this study. The single‐nucleotide polymorphisms rs2383207 and rs2383206 in 9p21 were genotyped in 499 CAG cases and 1519 controls in Chinese Han population. The gene dosage of 9p21 was stratified by the degree of vascular lesions and tested for association with the severity of CAD. Rs2383207 and rs2383206 demonstrated significant associations with 2‐vessel and 3‐vessel disease (P = 2.0×10?3 and 1.9×10?4, respectively). GG genotypes of rs2383206 occurred higher proportion of left main trunk (LM) disease (P = 6.0×10?3). GG genotypes of rs2383207 occurred higher proportion of left anterior descending artery disease (LAD) and right CAD (RCA) (P = 2.7×10?6 and 1.6×10?4, respectively). The risk allele G of rs2383207 was associated with severity of CAD estimated by the Gensini score (P = 3.6×10?5). Rs2383207 may strongly influence the development of CAD in Chinese Han population. The gene dosage in 9p21 could predict the severity of CAD. 相似文献
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