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This research was aimed at estimating possible Coal workers’ pneumoconiosis (CWP) cases as of 2012, and predicting future CWP cases among redeployed coal workers from the Fuxin Mining Industry Group. This study provided the scientific basis for regulations on CWP screening and diagnosis and labor insurance policies for redeployed coal workers of resource-exhausted mines. The study cohort included 19,116 coal workers. The cumulative incidence of CWP was calculated by the life-table method. Possible CWP cases by occupational category were estimated through the average annual incidence rate of CWP and males’ life expectancy. It was estimated that 141 redeployed coal workers might have suffered from CWP as of 2012, and 221 redeployed coal workers could suffer from CWP in the future. It is crucial to establish a set of feasible and affordable regulations on CWP screening and diagnosis as well as labor insurance policies for redeployed coal workers of resource-exhausted coal mines in China.  相似文献   
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Probiotics and Antimicrobial Proteins - This study aimed to elucidate the targets and mechanisms of anti-staphylococcal effects from bioactive metabolites produced by lactic acid bacteria. We aimed...  相似文献   
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The 5'-end region of cspA mRNA contains a Cold Box sequence conserved among several cold-shock mRNAs. This region forms a stable stem-loop structure followed by an AU-rich sequence. Here we show that the Cold Box region is essential for the normal scale of cspA mRNA induction after cold shock because a deletion of the stem-loop significantly destabilizes the mRNA and reduces the cold shock-induced cspA mRNA amount by approximately 50%. The AU-rich track, however, slightly destabilizes the mRNA. The integrity of the stem is essential for the stabilizing function, whereas that of the loop sequence is less important. Overexpression of a mutant cspA mRNA devoid of both the AUG initiation codon and the coding sequence results in a severe growth inhibition at low temperature along with a derepression of the chromosomal cspA expression. Furthermore, the overexpressed RNA is stably associated with the 30 S and 70 S ribosomes. Our results demonstrate that the AUG initiation codon and the coding region containing the downstream box are not required for cspA mRNA to bind ribosomes and that the 5'-untranslated region by itself has a remarkable affinity to ribosomes at low temperature.  相似文献   
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导水管周围灰质(periaqueductal gray,PAG)在疼痛的调控过程中处于一个不可或缺的位置.其不仅是痛觉信息上行传递的重要部位,还是疼痛抑制系统的重要组成部分.在PAG,包括γ-氨基丁酸(γ-aminobutyric acid,GABA)、5-羟色胺(5-hydroxytryptamine,5-HT)和谷氨酸(glutamate,Glu)在内的神经递质以及内源性阿片肽(endogenous opioid peptides,EOP)和内源性大麻素(endocannabinoid,e CB)为代表的神经调质都参与了PAG对疼痛的信息传递以及调节.本文重点综述GABA、5-HT、Glu、EOP和eCB在PAG参与疼痛生理调控机制的研究进展,以期为中枢神经系统的镇痛研究提供一定的理论基础.  相似文献   
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大鼠脊髓蛛网膜下腔注射α激动剂可乐宁1μg,引起血压降低、心率减慢及腹腔神经节后交感神经干放电抑制。应用α阻断剂酚妥拉明阻断脊髓内源性 NE的作用,可部分抑制血压升高时反射性的心率减慢和交感神经放电抑制反应,使压力感受器反射的敏感性降低。在颈动脉放血造成不可逆性失血性休克的动物,脊髓蛛网膜下腔注射酚妥拉明可使动脉血压有一定程度的回升。以上结果表明,由脊髓α受体调制的心血管抑制效应参与减压反射以及失血性休克的发病机制。  相似文献   
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A new species Dendrocalamus menglongensis Hsueh & K. L. Wang ex N. H. Xia, R. S. Lin &Y. B. Guo is described and illustrated from Xishuangbanna, Yunnan, China. It differs from D. giganteus by e.g. shorter internodes, 4–5 florets, a perfect terminal floret and persistent culm sheaths. A key to the new species and the other 7 species of Dendrocalamus known from Xishuangbanna is provided.  相似文献   
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行为实验已多次证明,脑室注射血管紧张素Ⅱ(AⅡ)可以对抗吗啡的镇痛作用,但机制不明。吗啡阻止神经末梢钙摄取被认为是其镇痛的机理之一,因此本工作研究了AⅡ和吗啡对大鼠脑突触小体~(45)Ca摄取的作用及相互关系。结果表明,吗啡(10~(-8)—10~(-6)mol/L)对~(45)Ca摄取有明显的抑制作用,10~(-7)mol/L时抑制41%(P<0.001),该效应可被吗啡受体阻断剂纳洛酮(10~(-6)mol/L)完全翻转。与吗啡的作用相反,AⅡ(10~(-8)—110~(-6)mol/L)可促进突触小体对~(45)Ca的摄取,10~(-7)mol/L时增加75%(P<0.001),该效应可被AⅡ受体阻断剂Saralasin(10~(-6)mol/L)完全翻转。将不同剂量的AⅡ(10~(-8)—10~(-6)mol/L)和10~(-8)mol/L吗啡与突触小体共同孵育,则吗啡抑制~(45)Ca摄取的作用被完全翻转。以上结果表明,AⅡ促进脑突触小体Ca~(2 )摄取,对抗了吗啡抑制Ca~(2 )摄取的作用,可能是AⅡ抗吗啡镇痛的机制之一。  相似文献   
10.
Bing Zhou  Nongan Chen  Qiliang Li 《Gene》1988,70(2):405-409
Partial digestion of a target DNA fragment with 4-bp-recognition restriction enzymes followed by a forced ligation to an M13 vector was employed for the construction of a subfragment library. The library can be used for either shotgun or non-random nucleotide sequencing. Application of the partial digests generated with the 4-bp recognition restriction enzymes instead of DNase I in the improved non-random strategy for nucleotide sequencing (Li and Wu, 1987) made the procedure as easy as that of the random strategy. The library can also be used in shotgun nucleotide sequencing directly, and few self-ligated subfragments were found. The usefulness of this procedure was demonstrated by the sequencing of a goat 6.5-kb EcoRI fragment, which is located 5' to the globin gene.  相似文献   
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