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International hospital-based studies have indicated a high risk of cognitive impairment after stroke, evidence from community-based studies in China is scarce. To determine the prevalence of post-stroke cognitive impairment (PSCI) and its subtypes in stroke survivors residing in selected rural and urban Chinese communities, we conducted a community-based, cross-sectional study in 599 patients accounting for 48% of all stroke survivors registered in the 4 communities, who had suffered confirmed strokes and had undergone cognitive assessments via the Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), and Hachinski Ischemia Scale (HIS). Detection of PSCI was based on scores in these neuropsychological scales. Factors potentially impacting on occurrence of PSCI were explored by comparing demographic characteristics, stroke features, and cardiovascular risk factors between patients with and without PSCI. The overall prevalence of PSCI was 80.97% (95%CI: 77.82%-84.11%), while that of non-dementia PSCI (PSCI-ND) and post-stroke vascular dementia (PSD) was 48.91% (95%CI: 44.91%-52.92%) and 32.05% (95%CI: 28.32%-35.79%), respectively. Prior stroke and complications during the acute phase were independent risk factors for PSCI. The risk of recurrent stroke survivors having PSCI was 2.7 times higher than for first-episode survivors, and it was 3 times higher for those with complications during the acute phase than for those without. The higher prevalence of PSCI in this study compared with previous Chinese studies was possibly due to the combined effects of including rural stroke survivors, a longer period from stroke onset, and different assessment methods. There is an urgent need to recognize and prevent PSCI in stroke patients, especially those with recurrent stroke and complications during the acute phase.  相似文献   
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Highly polymorphic microsatellite loci offer great promise for gene mapping studies, but fulfillment of this potential will require substantial improvements in methods for accurate and efficient genotyping. Here, we report a genotyping method based on fluorescently labeled PCR primers and size characterization of PCR products using an automated DNA fragment analyzer. We capitalize on the availability of three distinct fluorescent dyes to label uniquely loci that overlap in size, and this innovation increases by threefold the number of loci that can be analyzed simultaneously. We label size standards with a fourth dye and combine these with the microsatellite PCR products in each gel lane. Computer programs provide very rapid and accurate sizing of microsatellite alleles and efficient data management. In addition, fluorescence signals are linear over a much greater range of intensity than conventional autoradiography. This facilitates multiplexing of loci (since signal intensities often vary greatly) and helps distinguish major peaks from artifacts, thereby improving genotyping accuracy.  相似文献   
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灭幼脲Ⅲ号在好气水环境中的降解代谢的初步研究   总被引:1,自引:1,他引:0  
本文研究了新农药灭幼脲Ⅲ号在好气水环境中的降解与代谢。在避光条件下,观察了灭菌组与实验组中灭幼脲Ⅲ号及其主要代谢产物的消长过程,比较了它的化学水解与微生物降解的差异。在室内模拟好气系统中,研究了母体化合物在水体中的残留动态和生物降解半衰期,及其初期主要代谢途径的转化产物,同时分别用高效液相色谱法,紫外吸收光谱扫描,以及特征有机质谱图,对灭幼脲Ⅲ号的两种主要代谢产物进行了定性定量测定。结果表明:灭幼脲Ⅲ号在室内好气环境中较易水解,而且水中微生物的存在能加速它的降解,母体化合物在水体中初期代谢主要途径为分子中的苯甲酰碳与脲氮键首先开裂,生成邻氯苯甲酸(CBA)和对氯苯基脲素(CPU)。  相似文献   
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用频率为2450MHz功率密度为10mW/Cm~2(WBASAR约11.4W/kg)的微波(连续波)对置于微波暗室内的昆明种雄性小鼠急性全身照射1小时后,立即按常规方法断头,取脑,制成样品,然后用放射免疫测定法测量小鼠脑内乙酰胆碱(ACh)含量及胆碱乙酰转移酶(ChAT)活性。结果表明:照射组的ACh含量为11.6±1.4pmol/mg(脑鲜重),ChAT活性为45.4±8.7pmolACh/min.mg(脑鲜重);而对照组的分别为16.0±2.1pmol/mg和61.0±13.8pmolACh/min.mg。证明微波照射后可引起动物脑内ACh水平和ChAT活性下降,提示微波辐射对中枢胆碱能系统确有不利影响。  相似文献   
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森林土壤氮转化的微生物功能研究   总被引:2,自引:1,他引:1  
本文研究了不同林型下土壤(A+6层和A_1层)微生物、土壤酶活性在森林土壤氮转化中的作用。结果表明不同林型下土壤具有不同的固氮作用、反硝化作用、氨化作用和硝化作用速率,即阔叶林>针阔混交林>针叶林。已经证明,固氮作用主要存在于森林土壤的A_1层,反硝化作用主要存在于A_0层。森林土壤存在2种硝化作用过程,即由自养微生物所引起的自养硝化作用过程和异养微生物所引起的异养硝化作用过程。它的存在与林型有关,某些森林土壤中这2种硝化作用过程都存在,如针阔混交林下的A_0层和A_1层。有些林型下土壤,则以异养硝化作用过程为主,如针叶林的A_0层。  相似文献   
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中国大鲵视网膜的光镜和扫描电镜研究   总被引:7,自引:0,他引:7  
用光镜和扫描电镜观察了大鲵视网膜各类细胞的形态及分布, 对视细胞和节细胞进行计数。视网腊中三个核层及两个网状层分布均匀,无中央凹。每张视网膜的视细胞总数约130000,节细胞约8000,视杆与视锥之比为8.5:1。扫描电镜下,视杆外节表面的小叶间沟清晰;视杆视锥外节均有从内节伸出的20-30条萼状突起;核周体表面亦有20-30条细胞质突起。文中还报道了幼体视细胞的形态及密度。讨论了上述结构的机能。  相似文献   
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In the radioreceptor assay for growth hormone (RRA-GH) using [125I]iodo-hGH, hGH and human liver membrane particulate fractions as tracer, hormone standard and receptors, respectively, ovine placental lactogen (oPL) is capable of inhibiting the binding of [125I]iodo-hGH in a parallel manner with hGH and in equipotency. Similarly, in the RRA-GH by employing [125I]iodo-oPL, oPL and human liver membrane particulate fractions as tracer, hormone standard and receptors, respectively, hGH is also equipotent as oPL in inhibiting the binding of [125I]iodo-oPL in a parallel fashion. The addition of monoclonal antibodies against oPL in the assay was effective in inhibiting the binding of [125I] iodo-oPL to human liver, but could not, however, inhibit the binding of [125I]iodo-hGH to human liver. Furthermore, the addition of the monoclonal antibodies in the RRA-GH did not affect the parallelism of the oPL standard but lowered the total binding of oPL. Our studies indicate that the structure of the binding sequence in oPL which binds to the GH receptor of human liver is not identical to the equivalent sequence of hGH and that the monoclonal antibodies compete with GH receptors in human liver for the binding of oPL.  相似文献   
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