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91.
Identification of regulatory elements within the minimal promoter region of the human endogenous ERV9 proviruses: accurate transcription initiation is controlled by an Inr-like element. 下载免费PDF全文
G La Mantia B Majello A Di Cristofano M Strazzullo G Minchiotti L Lania 《Nucleic acids research》1992,20(16):4129-4136
92.
孤离大鼠左侧颈动脉窦,采用侧脑室(LCV)注射α_1受体阻断剂酚苄明(phenoxybenzam-ine PBZ,2μg/20μl)或α_2受体阻断剂育亨宾(yohimbine Y,2μg/20μl),以颈动脉窦内压(ISP)-平均动脉压(MAP)关系曲线及其有关参数为指标,研究和分析了中枢α受体对颈动脉窦反射的影响。将所得ISP和MAP经Logistic方程拟合,建立ISP-MAP关系曲线。结果如下:PBZ组,ISP-MAP关系曲线在高窦内压区明显上移;峰斜率、MAP变动范围明显减小;ISP-斜率关系曲线在15.96kPa处明显下移。Y组,ISP-MAP关系曲线在高窦内压区明显上移;峰斜率、MAP变动范围明显减小,阈压明显增大,ISP-斜率关系曲线在10.64、15.96kPa处明显下移。与PBZ组相比,Y组的峰斜率、MAP变动范围减小更明显。结果表明:中枢α_1或α_2受体阻断后,窦反射的敏感性明显降低,其中阻断α_2受体的作用尤为明显。 相似文献
93.
桑树叶肉原生质体培养再生植株 总被引:11,自引:0,他引:11
近年来,木本植物原生质作诱导再生植株的研究越来越受到国内外学者关注。但在林木树种中,迄今成功的种类仍然不多,在文 相似文献
94.
Regional expression of the homeobox gene Nkx-2.2 in the developing mammalian forebrain. 总被引:11,自引:0,他引:11
M Price D Lazzaro T Pohl M G Mattei U Rüther J C Olivo D Duboule R Di Lauro 《Neuron》1992,8(2):241-255
95.
96.
M Bernardi B Di Sarra G Montecchiani L Re L Rossini C Tonnini 《Bollettino della Società italiana di biologia sperimentale》1991,67(1):47-54
Spontaneous fluctuations in heart rate were analyzed by spectral analysis in the ether anesthetized and pithed adult rat. In order to investigate the changes in the spectral pattern of the fluctuations, the selective 5HT-2 and -3 isoreceptor blockers ritanserin and BRL 43694A were used. In both the experimental conditions, ritanserin blockade led to dose-dependent increased fluctuations in HR low and high frequencies. In both the anesthetized and pithed rats, the low frequency range HR fluctuations were drastically reduced by BRL 43694A. 相似文献
97.
R Fiorella G Assennato V Di Nicola M Troia G A Colucci L Resta 《Bollettino della Società italiana di biologia sperimentale》1991,67(2):199-205
The presence of inflammatory reaction, plasma cells, and eosinophils in peritumoral connective tissue and in neoplastic stroma was evaluated with morphometrical method in 181 patients affected by laryngeal carcinoma. A logistic multiple regression model was applied making it with the use of an independent variable represented by the "infiltrating" or "expansive" types of tumor growth, in order to evaluate the probability of nodal metastatsis of each parameter. The results suggest an inverse correlationship between plasma cells and inflammatory infiltration and incidence of nodal metastatsis only in the comparison of the extreme conditions: those with scarce infiltration versus the ones with large infiltration. Inflammatory or plasmacellular infiltration may represent both a defense mechanism against cancer and an aspecific or allergic reaction. The eosinophilic infiltration shows no value in the prevention of nodal involvement. 相似文献
98.
99.
Summary
Pleurotus florida was grown in submerged culture with different concentrations of sugar beet pulp with a view to its nutritional upgrading.
Micelial growth, protein enrichment and dry weight loss of the solid residues of cultures, as well as the evolution of reducing
sugars in the liquid medium, were followed for 14 days. A product with 45% (w/w) protein and a saccharification extent as
high as 35% (w/w) were obtained after 7 days with 1% (w/v) sugar beet pulp. 相似文献
100.