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991.

Objective

To explore the associations of green tea and rock tea consumption with risk of impaired fasting glucose (IFG) and impaired glucose tolerance (IGT).

Methods

A multistage, stratified, cluster, random-sampling method was used to select a representative sample from Fujian Province in China. In total, 4808 subjects without cardiovascular disease, hypertension, cancer, or pancreatic, liver, kidney, or gastrointestinal diseases were enrolled in the study. A standard questionnaire was used to gather data on tea (green, rock, and black) consumption and other relevant factors. The assessment of impaired glucose regulation (IGR) was using 75-g oral glucose tolerance test (OGTT), the diagnostic criteria of normal glucose tolerance was according to American Diabetes Association.

Results

Green tea consumption was associated with a lower risk of IFG, while rock tea consumption was associated with a lower risk of IGT. The adjusted odds ratios for IFG for green tea consumption of <1, 1–15, 16–30, and >30 cups per week were 1.0 (reference), 0.42 (95% confidence intervals (CI) 0.27–0.65), 0.23 (95% CI, 0.12–0.46), and 0.41 (95% CI, 0.17–0.93), respectively. The adjusted odds ratios for IGT for rock tea consumption of <1, 1–15, 16–30, and >30 cups per week were 1.0 (reference), 0.69 (95% CI, 0.48–0.98), 0.59 (95% CI, 0.39–0.90), and 0.64 (95% CI, 0.43–0.97), respectively. A U-shaped association was observed, subjects who consumed 16–30 cups of green or rock tea per week having the lowest odds ratios for IFG or IGT.

Conclusions

Consumption of green or rock tea may protect against the development of type 2 diabetes mellitus in Chinese men and women, particularly in those who drink 16–30 cups per week.  相似文献   
992.
中国美利奴(新疆军垦型)绵羊9个微卫星基因座多态性研究   总被引:10,自引:1,他引:10  
赵宗胜  王根林  郭继刚  李大全 《遗传》2006,28(8):939-944
利用PCR技术和复合电泳银染技术检测中国美利奴(新疆军垦型)绵羊第1号染色体上BM6506,BM1824,BM6438, ILSTS004和OarDB6 等5个基因座和第6号染色体上 BM4621,OarHH55,BM143和OarJMP8 等4个基因座,共9个基因座的基因频率(Pi)、个体鉴别力(DP)、杂合度(H)、多态信息含量(PIC)、和非父排除概率(PE)。结果显示:9个微卫星基因座的基因型分布符合Hardy-Weinberg平衡,绵羊中9个微卫星基因座中BM4621 基因座的DP、H、PIC和PE都为最高。9个微卫星基因座的累积个体鉴别力(CDP)为0.99999,累积非父排除能力(CPE)为0.99915。结果显示9个微卫星基因座适用于中国美利奴(新疆军垦型)绵羊的遗传连锁分析、个体识别和亲权鉴定等研究领域。  相似文献   
993.
从31个60岁以上的符合中华医学会老年医学分会健康老年人标准的健康老人中随机选取4例作为研究对象,使用分子生物学方法,对他们的肠道双歧杆菌和乳杆菌种群多样性进行分析.研究结果表明,健康老人肠道中双歧杆菌的优势种群为长双歧杆菌(Bifi∥dobacterium longum)和假小链双歧杆菌(Bifidobacterium pseudocatenulatum),分别占双歧杆菌种群的55%和45%;而肠道乳杆菌则有唾液乳杆菌(Lactobacillus salivarius)50%、Lactobacillus mocosae 31.1%、口腔乳杆菌(Lactobacillus oris)6.3%、鼠李糖乳杆菌(Lactobacillus rhamnosus)6.3%和瑞士乳杆菌(Lactobacillus helveticus)6.3%,其中唾液乳杆菌、Lactobacillus mocosae为健康老人肠道优势乳杆菌种群.  相似文献   
994.
气候变化背景下松嫩平原玉米灌溉需水量估算及预测   总被引:2,自引:0,他引:2  
黄志刚  肖烨  张国  曹云  彭保发 《生态学报》2017,37(7):2368-2381
开展农作物需水规律研究对于干旱半干旱区域旱作物节水灌溉和水分管理实践具有重要意义。以松嫩平原玉米为研究对象,研究玉米生育期需水量规律及灌溉需水量。结果表明:(1)历史时期和未来气候变化情景下,松嫩平原玉米全生育期和L~(mid)时段灌溉需水量等值线沿西南—东北方向递减,其中全生育期和L~(mid)时段2000s灌溉需水量临界等势线(灌溉需水量为0的等势线)分别比1970s北移70.2km和53.4km,全生育期和L~(mid)时段2040s灌溉需水量临界等势线分别比2010s北移30.9km和55.2km。(2)历史时期和气候变化情景下玉米全生育期灌溉需水量随年代呈波动增加趋势,其中前者以29.1mm/(10a)速度增加,后者以17.5mm/(10a)速度增加。(3)未来温度和降雨量变化对玉米需水量的贡献率为波动上升趋势,与1970s相比,2000s温度和降雨量变化对玉米需水量的贡献率为22.1%,增加6.8亿m~3灌溉水量;2040s温度和降雨量变化对玉米需水量的贡献率为38.3%,增加12.6亿m~3灌溉水量。  相似文献   
995.
Peng  Yawen  Guo  Genhua  Shu  Bin  Liu  Daiqiang  Su  Peng  Zhang  Xuming  Gao  Feng 《Neurochemical research》2017,42(11):3254-3267

CX3CL1 (fractalkine), the sole member of chemokine CX3C family, is implicated in inflammatory and neuropathic pain via activating its receptor CX3CR1 on neural cells in spinal cord. However, it has not been fully elucidated whether CX3CL1 or CX3CR1 contributes to the development of morphine tolerance. In this study, we found that chronic morphine exposure did not alter the expressions of CX3CL1 and CX3CR1 in spinal cord. And neither exogenous CX3CL1 nor CX3CR1 inhibitor could affect the development of morphine tolerance. The cellular localizations of spinal CX3CL1 and CX3CR1 changed from neuron and microglia, respectively, to all the neural cells during the development of morphine tolerance. A microarray profiling revealed that 15 members of chemokine family excluding CX3CL1 and CX3CR1 were up-regulated in morphine-treated rats. Our study provides evidence that spinal CX3CL1 and CX3CR1 may not be involved in the development of morphine tolerance directly.

  相似文献   
996.
Biomechanics and Modeling in Mechanobiology - Computational models have been used to calculate plaque stress and strain for plaque progression and rupture investigations. An intravascular...  相似文献   
997.
马铃薯块茎切片- 软腐病菌亲和互作过程中, 不同强度的亲和互作中活性氧的释放有其不同的特点。在强亲和互作中的24 小时内,无明显的活性氧释放。但在弱亲和互作中,互作8 小时后,即有明显的活性氧的释放,20 小时达到高峰,并且这种活性氧的释放提高寄主的抗病性。试验显示马铃薯块茎切片与软腐病菌的亲和互作诱导寄主抗氰交替途径的运行,SHAM 处理降低亲和互作过程中寄主的感病性, 同时SHAM 处理也促进亲和互作中寄主活性氧释放高峰的出现, 表明抗氰交替途径的运行可通过抑制亲和互作中寄主活性氧的产生而促进寄主的感病性。从而证明了一种新的寄主植物抗感病反应机制  相似文献   
998.
为探讨bcl┐2基因断裂与鼻咽癌发生的关系,采用分子原位杂交技术检测41例鼻咽癌组织bcl┐2基因的两个断裂热点。结果显示41例鼻咽癌发生bcl┐2基因断裂有4例,阳性率为9.8%,各组织学分级间无明显差异。鼻咽良性病变为阴性。结果说明bcl┐2基因断裂非淋巴瘤的特异性改变,bcl┐2基因断裂与鼻咽癌细胞的分化程度和恶性生物学行为间无明显关系,在鼻咽癌发生过程中的作用有限  相似文献   
999.
Root distribution and interactions between intercropped species   总被引:28,自引:0,他引:28  
Li L  Sun J  Zhang F  Guo T  Bao X  Smith FA  Smith SE 《Oecologia》2006,147(2):280-290
Even though ecologists and agronomists have considered the spatial root distribution of plants to be important for interspecific interactions in natural and agricultural ecosystems, few experimental studies have quantified patterns of root distribution dynamics and their impacts on interspecific interactions. A field experiment was conducted to investigate the relationship between root distribution and interspecific interactions between intercropped plants. Roots were sampled twice by auger and twice by the monolith method in wheat (Triticum aestivum L.)/maize (Zea mays L.) and faba bean (Vicia faba L.)/maize intercropping and in sole wheat, maize, and faba bean up to 100 cm depth in the soil profile. The results showed that the roots of intercropped wheat spread under maize plants, and had much greater root length density (RLD) at all soil depths than sole wheat. The roots of maize intercropped with wheat were limited laterally, but had a greater RLD than sole-cropped maize. The RLD of maize intercropped with faba bean at different soil depths was influenced by intercropping to a smaller extent compared to maize intercropped with wheat. Faba bean had a relatively shallow root distribution, and the roots of intercropped maize spread underneath them. The results support the hypotheses that the overyielding of species showing benefit in the asymmetric interspecific facilitation results from greater lateral deployment of roots and increased RLD, and that compatibility of the spatial root distribution of intercropped species contributes to symmetric interspecific facilitation in the faba bean/maize intercropping. Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   
1000.
He JS  Fang J  Wang Z  Guo D  Flynn DF  Geng Z 《Oecologia》2006,149(1):115-122
Nitrogen (N) and carbon–nitrogen (C:N) ratio are key foliar traits with great ecological importance, but their patterns across biomes have only recently been explored. We conducted a systematic census of foliar C, N and C:N ratio for 213 species, from 41 families over 199 research sites across the grassland biomes of China following the same protocol, to explore how different environmental conditions and species composition affect leaf N and C:N stoichiometry. Leaf C:N stoichiometry is stable in three distinct climatic regions in Inner Mongolia, the Tibetan Plateau, and Xinjiang Autonomous Region, despite considerable variations among co-existing species and among different vegetation types. Our results also show that life form and genus identity explain more than 70% of total variations of foliar N and C:N ratio, while mean growing season temperature and growing season precipitation explained only less than 3%. This suggests that, at the biome scale, temperature affects leaf N mainly through a change in plant species composition rather than via temperature itself. When our data were pooled with a global dataset, the previously observed positive correlation between leaf N and mean annual temperature (MAT) at very low MATs, disappeared. Thus, our data do not support the previously proposed biogeochemical hypothesis that low temperature limitations on mineralization of organic matter and N availability in soils lead to low leaf N in cold environments.  相似文献   
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