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41.
反复电针对慢性痛的累加治疗作用及其机制研究   总被引:22,自引:0,他引:22  
罗非 《生理科学进展》1996,27(3):241-244
本研究从基础和临床两方面观察了反复电针对慢性痛的累加治疗作用,并结合疼痛患者及慢性痛动物模型中几种神经肽的放射免疫测定及相应受体拮抗剂的药理学研究结果,探讨了产生累加效应的可能机制。结果表明,在临床脊髓损伤性痉挛患者,100Hz穴位体表电刺激有效地缓解痉挛并有累加效应;在临床慢性痛患者,2/15Hz变频TENS刺激有效地治疗疼痛并具有累加效应。在关节炎模型大鼠,电针刺激能产生明显的镇痛并具有累加效  相似文献   
42.
Evidence for genetic anticipation has recently become an important subject of research in clinical psychiatric genetics. Renewed interest in anticipation was evoked by molecular genetic findings of a novel type of mutation termed "unstable DNA." The unstable DNA model can be construed as the "best fit" for schizophrenia twin and family epidemiological data. We have performed a large-scale Southern blot hybridization, asymmetrical PCR-based, and repeat expansion-detection screening for (CAG)n/(CTG)n and (CCG)n/(CGG)n expansions in eastern Canadian schizophrenia multiplex families demonstrating genetic anticipation. There were no differences in (CAG)n/(CTG)n and (CCG)n/(CGG)n pattern distribution either between affected and unaffected individuals or across generations. Our findings do not support the hypothesis that large (CAG)n/(CTG)n or (CCG)n/(CGG)n expansions are the major etiologic factor in schizophrenia. A separate set of experiments directed to the analysis of small (30-130 trinucleotides), Huntington disease-type expansions in individual genes is required in order to fully exclude the presence of (CAG)n/(CTG)n- or (CCG)n/(CGG)n-type unstable mutation.  相似文献   
43.
We have determined the chromosomal localization of the gene for the catalytic subunit Cα of cAMP-dependent protein kinase (locus PRKACA) to human chromosome 19 using polymerase chain reaction (PCR) and Southern blot analysis of two different somatic cell hybrid mapping panels. In addition, PCR analysis of a chromosome 19 mapping panel revealed the presence of a human Cα-specific amplification product only in cell lines containing the region 19p13.1 to 19q12. Finally, two-color fluorescencein situhybridization to metaphase chromosomes using the human Cα cDNA and human chromosome 19 inter-Alu-PCR product as probes localized the human Cα gene to chromosome region 19p13.1.  相似文献   
44.
In the present study we have characterized the synthesis of members of the HSP30 family during Xenopus laevis development using a polyclonal antipeptide antibody derived from the carboxyl end of HSP30C. Two-dimensional PAGE/immunoblot analysis was unable to detect any heat-inducible small HSPs in cleavage, blastula, gastrula, or neurula stage embryos. However, heat-inducible accumulation of a single protein was first detectable in early tailbud embryos with an additional 5 HSPs at the late tailbud stage and a total of 13 small HSPs at the early tadpole stage. In the Xenopus A6 kidney epithelial cell line, a total of eight heat-inducible small HSPs were detected by this antibody. Comparison of the pattern of protein synthesis in embryos and somatic cells revealed a number of common and unique heat inducible proteins in Xenopus embryos and cultured kidney epithelial cells. To specifically identify the protein product of the HSP30C gene, we made a chimeric gene construct with the Xenopus HSP30C coding sequence under the control of a constitutive promoter. This construct was microinjected into fertilized eggs and resulted in the premature and constitutive synthesis of the HSP30C protein in gastrula stage embryos. Through a series of mixing experiments, we were able to specifically identify the protein encoded by the HSP30C gene in embryos and somatic cells and to conclude that HSP30C synthesis was first heat-inducible at the early tailbud stage of development. The differential pattern of heat-inducible accumulation of members of the HSP30 family during Xenopus development suggests that these proteins may have distinct functions at specific embryonic stages during a stress response.  相似文献   
45.
将菠菜叶片匀浆后.用差速离心和梯度率心分离叶绿体、过氧物酶体、微粒体等细胞器和100000×g上清法部分。用酶活测定法测定各部分甜菜碱醛脱氢酶(BADH)的活性;用免疫扩散法鉴定各组分的BADH。除叶绿体外,过氧物酶体、微粒体.以及100000×g上清液中也存在BADH。  相似文献   
46.
以7690-Xu荧光染色法结合WuT3、WuT4、WuT8致敏红细胞花环实验观察经胸腺细胞分层液分离所得高密度亚群和低密度亚群人胎胸腺细胞的异质性荧光及其膜分化抗原CD3、CD4、CD8的表达。结果表明:不同胎龄胎儿胸腺细胞悬液呈现相似形态和相似分布特征的8种异质性荧光的细胞,其中,墨黑核细胞和桔红核细胞分布于两密度亚群,表型为CD3-CD4-CD8-;少数深蓝核和蓝核细胞分布于低密度亚群.表型为CD3+,属成熟的胸腺细胞;大多数深蓝核和蓝核细胞、灰蓝核细胞、灰黄核细胞及部分淡桔黄核细胞分布于高密度亚群,表型为CD3-、CD4+、CD8+,为处于中间发育阶段的胸腺细胞。推测这些细胞胞核由深蓝、蓝、灰蓝、灰黄到淡桔黄的荧光光谱的偏移可能与中间发育阶段所发生的生物及理化变化有关。  相似文献   
47.
鳗鱼肌肉的氨基酸及营养价值   总被引:7,自引:1,他引:6  
通过对优质食用鱼类—鳗鱼肌肉的氨基酸进行测定证实,鳗鱼较之其它鱼类是一种营养价值更高、滋味更鲜美的鱼类。并且,根据结果氨基酸组成比例,可为鳗鱼的人工饲养等方面的研究提供理论依据。  相似文献   
48.
用中性红标记酵母原生质体初探   总被引:1,自引:0,他引:1  
吴根福  沈煜 《生物技术》1995,5(6):23-25,12
用2%蜗牛酶处理酵母细胞60分钟,啤酒酵母Y29的原生质体形成率为90%,再生率为9.5%;糖化酵母IB的原生质体形成率为86%,再生率为12%。用500ppm中性红染液对Y29菌株的整细胞和原生质体染色15分钟,细胞的着色率为84%,存活率为12%,而原生质体的着色率为75%,再生率为6.4%,经染色后的原生质体体积缩小,在交变电场中排队所需的场强电降低。  相似文献   
49.
The phylogenetic relationships among Primates (human), Artiodactyla (cow), Cetacea (whale), Carnivora (seal), and Rodentia (mouse and rat) were estimated from the inferred amino acid sequences of the mitochondrial genomes using Marsupialia (opossum), Aves (chicken), and Amphibia (Xenopus) as an outgroup. The overall evidence of the maximum likelihood analysis suggests that Rodentia is an outgroup to the other four eutherian orders and that Cetacea and Artiodactyla form a clade with Carnivora as a sister taxon irrespective of the assumed model for amino acid substitutions. Although there remains an uncertainty concerning the relation among Artiodactyla, Cetacea, and Carnivora, the existence of a clade formed by these three orders and the outgroup status of Rodentia to the other eutherian orders seems to be firmly established. However, analyses of individual genes do not necessarily conform to this conclusion, and some of the genes reject the putatively correct tree with nearly 5% significance. Although this discrepancy can be due to convergent or parallel evolution in the specific genes, it was pointed out that, even without a particular reason, such a discrepancy can occur in 5% of the cases if the branching among the orders in question occurred within a short period. Due to uncertainty about the assumed model underlying the phylogenetic inference, this can occur even more frequently. This demonstrates the importance of analyzing enough sequences to avoid the danger of concluding an erroneous tree.  相似文献   
50.
At elevated atmospheric CO2 concentrations ([CO2]a), photosynthetic capacity (Amax) and root fraction (ηR, the ratio of root to plant dry mass) increased in some studies and decreased in others. Here, we have explored possible causes of this, focusing on the relative magnitudes of the effects of elevated [CO2]a on specific leaf (nm) and plant (np) nitrogen concentrations, leaf mass per unit area (h), and plant nitrogen productivity (α). In our survey of 39 studies with 35 species, we found that elevated [CO2]a led to decreased nm and np in all the studies and to increased h and α in most of the studies. The magnitudes of these changes varied with species and with experimental conditions. Based on a model that integrated [CO2]a-induced changes in leaf nitrogen into a biochemically based model of leaf photosynthesis, we predicted that, to a first approximation, photosynthesis will be upregulated (Amax will increase) when growth at increased [CO2]a leads to increases in h that are larger than decreases in nm. Photosynthesis will be downregulated (Amax will decrease) when increases in h are smaller than decreases in nm. The model suggests that photosynthetic capacity increases at elevated [CO2]a only when additional leaf mesophyll more than compensates the effects of nitrogen dilution. We considered two kinds of regulatory paradigms that could lead to varying responses of ηR to elevated [CO2]a, and compared the predictions of each with the data. A simple static model based on the functional balance concept predicts that ηR should increase when neither np nor h is very responsive to elevated [CO2]a. The quantitative and qualitative agreement of the predictions with data from the literature, however, is poor. A model that predicts ηR from the relative sensitivities of photosynthesis and relative growth rate to elevated [CO2]a corresponds much more closely to the observations. In general, root fraction increases if the response of photosynthesis to [CO2]a is greater than that of relative growth rate.  相似文献   
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