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1.
AMPK在妊娠期糖尿病发病机制中的作用   总被引:1,自引:0,他引:1  
腺苷酸活化蛋白激酶是一种重要的蛋白激酶,主要作用是协调代谢和能量平衡.腺苷酸活化蛋白激酶被激活后,在增加骨骼肌对葡萄糖摄取、增强胰岛素敏感性、增加脂肪酸氧化以及调节基因转录等方面发挥重要作用.已经证实脂联素有调节糖脂代谢的作用,但其作用机制尚不十分清楚,很可能是通过腺苷酸活化蛋白激酶介导,对脂联素信号转导通路的研究将成为进一步理解脂联素作用的关键所在.而脂联素又是妊娠期糖尿病的预测因子,所以腺苷酸活化蛋白激酶逐渐成为对妊娠期糖尿病研究中的焦点.  相似文献   
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Chemotactic behavior of Campylobacter jejuni.   总被引:2,自引:3,他引:2       下载免费PDF全文
The chemotactic behavior of Campylobacter jejuni was determined in the presence of different amino acids, carbohydrates, organic acids, and preparations and constituents of mucin and bile. L-Fucose was the only carbohydrate and L-aspartate, L-cysteine, L-glutamate, and L-serine were the only amino acids producing a chemotactic (positive) response. Several salts of organic acids, including pyruvate, succinate, fumarate, citrate, malate, and alpha-ketoglutarate, were also chemoattractants, as were bile (beef, chicken, and oxgall) and mucin (bovine gallbladder and hog gastric). Most constituents of bile tested individually were chemorepellents, but the mucin component was chemoattractant. The chemotactic behavior of C. jejuni toward L-fucose, a constituent of both bile and mucin, may be an important factor in the affinity of the organism for the gallbladder and intestinal tract.  相似文献   
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藏汉民族线粒体基因组全序列的比较研究   总被引:1,自引:0,他引:1  
目的 以藏汉民族线粒体基因组全序列为基础,进行Haplogroup构建和系统发生分析,在全序列水平上比较核苷酸的变异,阐释可能的变异机制和蕴含的生物学意义.方法 采用Applied Biosystems 3730DNA自动测序仪分别对40名藏族和50名汉族的标本进行线粒体DNA序列测定,应用phredPhrap 16.0软件进行全序列拼接,并以rCRS(revised Cambridge Reference Sequence)为标准与测定序列进行比对分析;根据MTTO-MAP的标准,通过Network方法进行Haplogroup构建和系统发生的分析,并结合其它方法对产生的数据进行深入解读.结果 数据分析结果显示:在系统发生上,藏汉民族90个线粒体DNA序列归类到13个Haplogroups,除M9以外,其它各Haplogroup出现频率之间比较差异无统计学意义;通过两个民族的线粒体DNA全序列比对,发现21个分布频率有统计学意义的变异位点,其中的5个为新变异位点;另外,对D-Loop区的5个突变位点进行了单倍型构建,90个标本可分为2种Supertype,发现在藏汉民族之间Supertypel和Supertype 2的分布频率均有统计学意义.结论 藏汉民族在种族起源和系统发生上具有较近的母系遗传关系;在全序列有统计学意义的位点究竟是适应性或者中性选择,抑或是一种病理性突变尚需深入的探讨.  相似文献   
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Journal of Community Health - The purpose of this study was to evaluate family physicians’ job strain during the Covid-19 pandemic and determine the effective factors. The study was carried...  相似文献   
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松质骨中两种纵波的传播特性分析   总被引:2,自引:1,他引:2  
基于松质骨的层状模型,利用Schoenberg理论分析了松质骨中两种纵波(快纵波和慢纵波)的传播特性;并在理论和实验上详细分析了骨小梁方向与传播方向间的夹角对松质骨中快纵波和慢纵波传播特性的影响。分析结果表明,当超声波平行于骨小梁入射时,松质骨中两种纵波都传播,入射角度在60度附近时,松质骨中两种纵波的相速度曲线有一个转折点,入射角度在60度以上,角度越大时,骨髓和骨小梁耦合得越紧,因此阻止了慢纵波的传播,而只有快纵波传播。  相似文献   
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OBJECTIVE: The purpose of this study was to examine the influence of traumatic grief on suicidal ideation. METHOD: The Beck-Kovacs Scale for Suicidal Ideation was administered to 76 young adult friends of suicide victims. RESULTS: Traumatic grief was associated with a 5.08 times greater likelihood of suicidal ideation, after control for depression. Comorbid traumatic grief and depression were not associated with a greater likelihood of suicidal ideation. CONCLUSIONS: Syndromal traumatic grief heightens vulnerability to suicidal ideation.  相似文献   
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PURPOSE. The purpose of this study is to identify the kinds of community organizations community leaders consider important for community health promotion efforts. DESIGN. Key informants were identified by reputational sampling of organizations relevant to community health promotion. Key informants were asked to list organizations they considered important for community health promotion. Differences in identified organizations were compared across informants from seven urban, five suburban, seven rural, and three Native American communities, with significance evaluated by chi-square tests. SETTING. This survey was conducted in 22 Western U.S. communities comprising the intervention and control communities of the Community Health Promotion Grants Program of the Henry J. Kaiser Family Foundation. SUBJECTS. Key informants (N = 184) from community organizations, identified using a reputational sampling technique beginning with the health department, were interviewed by telephone. MEASURES. Key informants listed organizations considered important for community health promotion in five areas: adolescent pregnancy, substance abuse, tobacco use, cancer, and cardiovascular disease. RESULTS. Informants frequently identified the health department (mentioned by 78% of informants overall), schools (72%), governmental agencies (55%), hospitals (47%), health clinics (42%), churches (33%), and newspapers (32%) as important. Organizations more prominent in urban and suburban areas than in rural and Native American areas included television stations, health-related private nonprofit organizations, substance abuse treatment centers, and colleges. Private physicians were frequently identified in rural areas (44% of informants).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Postoperative speech function may be influenced by a number of treatment variables. The objective of this study was to examine the relationships among various treatment factors to determine the impact of these measures on speech function. Speech function was tested prospectively in 142 patients with surgically treated oral and oropharyngeal cancer 3 months after treatment. Each patient's speech was recorded during a 6- to 7-minute conversation and while performing a standard articulation test, producing speech outcome measures of percent correct consonant phonemes and percent conversational understandability. Correlational analyses were used to determine the relationships among the speech outcome measures and 14 treatment parameters. Speech function was mildly to moderately negatively correlated with most surgical resection variables, indicating that larger amounts of tissue resected were associated with worse speech function. Overall measures of conversational understandability and percent correct consonant phonemes were related to extent of oral tongue resection, floor of mouth resection, soft palate resection, and total volume of tissue resected. These relationships varied depending on the method of surgical closure. Method of surgical reconstruction had a profound impact on postoperative speech function 3 months after treatment and was an important factor in determining how oral tongue resection influenced articulation and intelligibility. The combination of closure type, percent oral tongue resected, and percent soft palate resected had the strongest relationship with overall speech function for patients with surgically treated oral and oropharyngeal cancer 3 months after treatment.  相似文献   
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