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191.
本文回顾性总结历史上几次世界性甲型流感流行和2009年H1N1流感流行情况。概述了2009年H1N1流感普通型病例的临床处理。重点阐述2009年H1N1流感重症型病例的高危人群、发生的危险因素以及临床表现。特别强调重症型流感抗病毒治疗的重要性及适应证。同时提醒关注神经氨酸酶抑制剂应用的耐药问题。  相似文献   
192.
利用128导事件相关电位技术,对19名正常被试在言语、峰鸣声和音乐刺激上产生的脑电早期外源性成分N1进行了考察。实验结果发现,在音素条件和蜂鸣声条件下,左侧额叶N1波幅显著高于右侧。偶极子溯源分析发现音素条件和蜂鸣声条件下的偶极子都位于左脑额叶,而音乐条件下的两个偶极子位于右脑额叶。证明范畴属性对信号加工大脑半球优势的影响在加工的早期就开始发挥作用。  相似文献   
193.
The aim of this study was to examine the effects of histaminergic antagonists on memory upon injection into the region of the nucleus basalis magnocellularis (NBM). In experiment 1, rats with chronically implanted cannulae were trained on the uphill avoidance task, which involves a punishment of a high-probability turning response on a tilted platform (negative geotaxis). Immediately after the training trial, that is, after a tail shock was administered upon performing the response, rats received one microinjection (0.5 microliter) of H1-receptor blocker chlorpheniramine (dose range 0.1 to 20 microgram) or the H2-receptor blocker ranitidine (same dose range) or saline into the NBM region. When tested 24 h later, rats treated with chlorpheniramine (20 micrograms) had significantly longer uphill latencies than vehicle controls and ranitidine-treated animals, indicative of superior learning of the avoidance response. In experiment 2, a test for possible proactive effects of posttrial chlorpheniramine on performance during the retention trial was performed. Animals were injected with either 20 micrograms chlorpheniramine or saline immediately after the training trial of the uphill task. One chlorpheniramine control group was treated with a delay of 5 h. Additional groups which received chlorpheniramine or vehicle after the training trial but no trail shock were included. When tested 24 h later, rats injected with 20 micrograms chlorpheniramine again exhibited significantly longer uphill latencies than did vehicle-injected rats. Retention latencies for the rats of the chlorpheniramine 5-h delayed group did not differ from those of the vehicle-injected rats, ruling out proactive effects of chlorpheniramine on performance. In summary, the histaminergic H1-blocker chlorpheniramine can enhance mnemonic functioning in addition to its reinforcing effects upon NBM injection as reported previously.  相似文献   
194.
问黎敏  安书成  刘慧 《心理学报》2012,44(10):1318-1328
为探讨慢性不可预见性温和应激(chronic unpredictable mild stress, CUMS)诱发抑郁样行为发生中海马5-羟色胺1A受体(5-hydroxytryptamine receptor 1A, 5-HT1AR)表达与作用, 及其对谷氨酸N-甲基-D-天冬氨酸(N-methyl-D-aspartic acid, NMDA)受体和α-氨基羟甲基异恶唑丙酸(α-amino-3-hydroxy-5- methylisoxazole-4-propionic acid, AMPA)受体的影响。通过建立CUMS动物模型, 给应激抑郁模型大鼠海马微量注射5-HT1A受体激动剂、给正常大鼠海马微量注射5-HT1A受体拮抗剂, 测量大鼠体重变化率, 并采用糖水偏爱测试、旷场实验和悬尾实验等方法对大鼠进行行为学检测, 运用Western blot和ELISA方法检测大鼠海马组织中5-HT1AR和NMDAR和AMPAR的关键亚基的表达以及磷酸化水平。结果显示, 与对照组相比, CUMS组大鼠表现出抑郁样行为, 海马5-HT1AR、AMPA受体的GluR2/3亚基表达及磷酸化明显降低, NMDA受体的NR1和NR2B亚基表达及磷酸化显著增加; 正常大鼠海马微量注射5-HT1A受体拮抗剂WAY100635, 动物行为学表现及AMPA受体、NMDA受体表达及磷酸化水平均与CUMS组相同; 注射5-HT1A受体激动剂8-OH-DPAT能逆转应激诱导的上述改变。以上结果表明, CUMS诱发抑郁样行为与海马5-HT1AR表达下降, AMPAR表达量及磷酸化水平降低, NMDAR表达量及磷酸化水平升高有关。5-HT通过5-HT1AR产生抗抑郁作用。5-HT1AR激动剂抗抑郁作用与降低NMDAR表达量及磷酸化水平, 提高AMPAR表达量及磷酸化水平密切相关。  相似文献   
195.
为了探讨MMP-2、TIMP-1在DMEH和DN发病中的意义,随机收集T2DM患者146例,其中SDM 57例,DMEH 38例,DN 51例,健康对照38例。用ELISA法测定MMP-2、TIMP-1的含量。结果显示,DM患者尤其是DMEH和DN患者血清MMP-2明显低于健康对照组,P均〈0.01,且随病情发展呈逐渐降低趋势。而血清TIMP-1随病情的发展则呈现明显的上升趋势,SDM、DMEH组和DN组与健康对照组比较,分别为P〈0.05,P〈0.01和P〈0.01。因此,MMP-2和TIMP-1可能参与了DMEH和DN的发生发展过程,定期检测DM患者血清MMP-2和TIMP-1的含量变化有助于DM并发症的早期诊断和疗效观察。  相似文献   
196.
Taxicab Correspondence Analysis   总被引:1,自引:0,他引:1  
Taxicab correspondence analysis is based on the taxicab singular value decomposition of a contingency table, and it shares some similar properties with correspondence analysis. It is more robust than the ordinary correspondence analysis, because it gives uniform weights to all the points. The visual map constructed by taxicab correspondence analysis has a larger sweep and clearer perspective than the map obtained by correspondence analysis. Two examples are provided. This research was financed by the Natural Sciences and Engineering Research Council of Canada. The author thanks Serge Vienneau for his help regarding the graphical displays, and also thanks the editor, associate editor, and two reviewers for their constructive comments.  相似文献   
197.
Fragile X syndrome is primarily due to a CGG repeat expansion found in the FMR1 X-linked gene. In a previous study, we conducted focus groups with women to assess their attitudes towards fragile X carrier screening. In this follow-up study, we conducted in-depth interviews of general population reproductive-age women who were identified as carriers. We explored their attitudes toward testing for carrier status of the fragile X mutation. These women underwent screening primarily to participate in a research project rather than in search of a diagnosis for specific symptoms. As such, these women were wholly unprepared for positive carrier results. Their responses about their results and carrier screening, in many cases, were being worked out over the course of the interview itself. The most salient finding of this work is the apparent lack of relevance of carrier status to these women. Many expressed that although the information could be relevant in the future, it is not relevant at this stage of their lives in terms of family planning (either with respect to having unaffected offspring or to premature ovarian failure) and personal relationships. Although issues of abortion seemed prominent in the focus groups, we found that carrier status did not have an apparent effect on women’s attitudes about termination. We hypothesize this may be related to the fact that women had not processed their new carrier status and had not related it to previously-formed personal opinions. The findings of this work have significant implications for genetic counseling and population screening. Genetic counselors should be mindful that general population women may not recognize the immediate importance of their carrier status even when literature is provided and discussed prior to providing a sample. As part of comprehensive genetic counseling, counselors should identify the reproductive life stage of the woman receiving the new information and help her identify when this information would be more meaningful in her life. Counselors can assist in setting up a personalized road map with specific types of services that will be more applicable to the woman as her carrier status becomes more relevant.  相似文献   
198.
This qualitative study explores how 29 Swedish patients with Multiple Endocrine Neoplasia type 1 (MEN1) experience living with the condition, appraisal of the clinical follow-up program, and surveys their future expectations. The aim of this study is to build knowledge about this patient group in order to provide optimal care. The participants describe physical, psychological, and social limitations in their daily activities and how these limitations influence quality of life. Our findings indicate that a majority of patients have adjusted to their situation, describing themselves as being healthy despite physical symptoms and treatment. The participants received decent care in the clinical follow-up program, - however, greater effort should be put into patient information. These patients might benefit from genetic counseling. Health professionals involved should recognize their potential impact and influence on a patient’s ability to adjust to these circumstances. Antonovsky`s Sense of Coherence theory is used to discuss these findings.  相似文献   
199.
The effect of force requirements on response effort was examined using outbred (CD-1) mice trained to press a disk with their snout. Lateral peak forces greater than 2 g were defined as threshold responses (i.e., all measured responses). Different force requirements were used to define criterion responses (a subclass of threshold responses) that exceeded the requirement. The reinforcer was sweetened, condensed milk, and it was delivered upon response termination. All mice were exposed to two ascending series of criterion force requirements (2, 4, 8, 16, and 32 g). Increasing the force requirement decreased criterion response rates, but increased threshold response rates. The time-integral of force (area under the force-time curve for individual responses, which is proportional to energy expenditure for each response) increased with the increase in the force requirement. These results conflict with the hypothesis that higher force requirements have aversive qualities and suggest that increased force requirements are more analogous to intermittent schedules of reinforcement. These data suggest that estimations of effort or energy expenditure should be measured independently of the force requirement. Individual differences in responding were found for the CD-1 outbred stock.  相似文献   
200.
高危型别人乳头瘤病毒(HPV)感染在宫颈癌发生发展中具有重要作用。由于HPV L1蛋白结构特征及其精确的抗原特性,在粘附宿主细胞、识别病毒受体、协助病毒DNA的入胞转运中均发挥重要作用。检测患者宫颈损伤组织中L1蛋白的表达将有助于对患者是否具有传染性进行评估。本文将深刻思考HPV L1功能及其在感染机体并引发癌变的机制,以期更好的解读宫颈癌发病原理并最终应用于,强床治疗。  相似文献   
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