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91.
Regulation of glycogenolysis in human skeletal muscle 总被引:7,自引:0,他引:7
The role of inorganic phosphate on the regulation of glycogenolysis in resting and contracting muscle was studied in human quadriceps muscle. Increased Pi content was achieved by intermittent electrical stimulation of the muscle followed by occlusion of the blood flow. Occlusion resulted in the maintenance of a high Pi content over a 60-s observation period during which the muscle was either at rest or was stimulated electrically. The study was performed with and without infusion of epinephrine (EPI). In the absence of EPI the phosphorylase a fraction was 50% immediately at the end of the initial stimulation period, declining to 22% after 60 s. With EPI corresponding values for phosphorylase a were 91% initially, 56% after 30 s, and 33% after 60 s, respectively. In both cases the Pi content was increased by approximately 35 mmol/kg dry muscle during the stimulation and remained constant during the occlusion. In neither of these situations was significant degradation of glycogen observed during the occlusion. In the study performed with electrical stimulation during the occlusion period, muscle glycogen degradation was observed both with and without EPI. Phosphorylase a fractions and Pi contents in this study were similar to those observed when muscle was rested over the 60-s occlusion period. The paradox of a high Pi content and extensive transformation of phosphorylase to the a form but low glycogenolytic activity points to additional factors in the regulation of glycogen breakdown. 相似文献
92.
93.
八倍体小黑麦×普通小麦杂种后代群体中的染色体易位 总被引:3,自引:0,他引:3
用改良的Giemsa C-带技术以单株为基础分析了八倍体小黑麦×普通小麦的杂种BC_1,F_(?)和F_(?)代植株的核型。在鉴定了C-带核型的1098株杂种后代植株中,发现了78条小麦-黑麦和277条黑麦-黑麦易位染色体。在不同的世代和株系中,小麦-黑麦染色体易位率变化在4.35—14.07%之间,平均7.10%;黑麦-黑麦染色体易位率在0.48—52.78%之间,平均25.23%。鉴定的小麦-黑麦易位染色体涉及了黑麦的14条不同的染色体臂和小麦的A、B和D组染色体。易位的48.57%发生在小麦和黑麦的部分同源染色体之间,51.43%发生在非部分同源染色体之间。不同的黑麦染色体臂参与易位的频率不同。小麦-黑麦染色体易位主要发生在杂种的早期世代,使用适当的选择技术在F_3获得了纯合的易位植株。文中讨论了快速选育易位系的技术和它们在小麦育种中的应用问题。 相似文献
94.
本文以抗人C_(?)的羊IgG为包被抗体,以HRP-HBs抗体为指示抗体,建立了可检测激活补体类HBsAg循环免疫复合物(HBsAg/C3-CIC)的C_3捕捉法酶联免疫吸附试验。检测了236例六种类型临床诊断为乙型肝炎的病人血清标本,其阳性率分别为:无症状携带者(ASC)12.9%(4/31),急性肝炎(AH)36.7%(22/60),慢性迁延性肝炎(CPH)33.3%(7/21),慢性活动性肝炎(CAH)59.6%(34/57),重型肝炎(SH)77.8%(14/18),肝炎后肝硬化(PLC)67.3%(33/49),阳性率与肝损严重程度明显相关(P<0.01)。认为HBs-Ag/C3-CIC可能在乙型肝炎病毒引起的慢性活动性肝炎、重型肝炎和肝炎后肝硬化的发病过程中起重要作用,并可作为乙型肝炎的诊断、临床分型和预后判断的指标之一。 相似文献
95.
96.
97.
用免疫荧光单克隆抗体对脊髓灰质炎病毒抗原表位的分析 总被引:1,自引:0,他引:1
用间接免疫荧光与中和试验筛选出来的抗脊髓灰质炎2型与3型不同毒株的12个单克隆抗体,其中3个仅有免疫荧光活性,9个具有中和与免疫荧光活性。用免疫荧光活性的单克隆抗体进行试验,发现它们在识别特异性抗原表位方面与中和性单克隆抗体相似,显示出株特异的、几个毒株共同特异的或型特异的抗原表位。根据表位分布关系及特征,可以用来鉴别型内毒株的特征、毒株的抗原分析、抗原变异的研究以及疫苗相关病例的鉴别。所得结果与中和性单克抗隆抗体及T1-寡核苷酸指纹图谱分析一致。而免疫荧光单克隆抗体识别抗原表位的活性范围比中和性单克隆抗体更广。另外还发现某些兼有荧光与中和两活性的同一个单克隆抗体,用不同方法(IF与NT)进行试验时,与相同毒株出现不同表位反应,这点是值得引起注意需待进一步证实的重要问题。 相似文献
98.
The authors examined relationships between Kira's warmth index (WI) and four other important thermal indices: the sums of
daily mean temperatures above 5°C and 10°C, Thornthwaite's potential evapotranspiration (PE) and Holdridge's annual biotemperature.
The thermal records of 671 meteorological stations evenly located all over China were used to make these comparisons. Close
correlations were found within the four relationships, and accordingly WI was used to analyse the thermal distributions of
the main vegetation types. Vegetation types around the 671 stations were read from a vegetation map with a scale of 1/4000000.
Vegetation types at 269 stations corresponded to the natural or seminatural vegetation, and 29 vegetation types were distinguished
by arranging the 269 data into the same or similar types. The geographical distribution of these 29 types and the corresponding
main climatic features were described. The relations between WI and distribution of these vegetation types were discussed
in detail. As a result, WI values (°C month) corresponding to the vegetation zones could be summarized as follows: (1) arctic
or alpine vegetation zone: 0–15; (2) boreal or subalpine vegetation zone: 15-(50–55); (3) cool-temperate vegetation zone:
(50–55)–(80–90); (4) warm-temperate vegetation zone: (80–90)–(170–180). These values almost coincided with Kira's values.
Chinese postgraduate student in Japan sent by the Chinese Government. 相似文献
99.
Surjit Singh Gernot Fritze Bingliang Fang Shoji Harada Yong K. Paik Rolf Eckey Dharam P. Agarwal H. Werner Goedde 《Human genetics》1989,83(2):119-121
Summary Genotyping of mitochondrial aldehyde dehydrogenase (ALDH I) was performed in enzymatically amplified DNA of 20 Chinese, Japanese and South Korean families (85 individuals) and in 113 unrelated persons by employing allele-specific oligonucleotide probes and dot blot hybridization. Genotyping individuals with phenotypic deficiency of ALDH I activity always showed the presence of at least one mutant allele. The data are compatible with a model assuming dominant inheritance of the mutant allele, which we have previously suggested on the basis of a population study. 相似文献
100.
瓜子金皂甙丙和丁的化学结构研究 总被引:1,自引:0,他引:1
自草药瓜子金(Polygala japonica Houtt)地上部分又分离得到两种皂甙,即瓜子金皂甙丙和皂甙丁,它们的分子式均为 C_(42)H_(68)O_(15),为同分异构物。两者酸水解均得瓜子金皂甙元和 D-葡萄糖,但碱水解时,只有皂甙丁可被水解,产物和酸水解相同。经~1HNMR,~(13)CNMR,MS 推定它们的结构式,瓜子金皂甙丙为3-O-[β-D-葡萄吡喃糖(1→2)-β-D-葡萄吡喃糖]瓜子金皂甙元;而瓜子金皂甙丁为28-O-[β-D-葡萄吡喃糖(1→2)-β-D-葡萄吡喃糖]瓜子金皂甙元。上述两种皂甙均为新化合物。 相似文献