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41.
42.
四川地区幼儿和学龄前儿童的鼻部测量 总被引:2,自引:0,他引:2
本文报告1116例四川地区幼儿和学龄前儿童(2-7岁)鼻部9项指标的测量均数,性差及年龄发育特点。性差:仅鼻凹鼻底距4-6.5岁等少数指标部分年龄段男女性间出现显著性划异(男>女)。此外各项指标的绝大多数年龄段男女性间无显著性差异。年龄发育:9项测量指标中7项的生长曲线随年产长而上升,数值随年龄增大,并有1-2个发育高峰;提示鼻部发育具有阶段性;2项指标的曲线随年龄增长变化较小。4项指标男女性的曲 相似文献
43.
Michael Fernandes Gaddo Onesti Roberto Fiorentini Giuseppe Bellini Anne B. Gould Kwan Eun Kim Charles Swartz 《Life sciences》1977,20(4):623-626
Renal hypertension was induced by ligation of the aorta between renal arteries in rats sympathectomized with 6-hydroxydopamine. In the early phase, equally severe hypertension developed in the denervated group as compared to innervated controls. Later, blood pressure was lower in the denervated rats. Initially, increases in plasma renin were seen in both groups; the levels, however, were markedly lower in the denervated rats. Later, the renin levels were similar and not different from baseline. It is concluded that adrenergic neural activity is not essential in the development of renal hypertension; the maintenance of the chronic state, however, depends in part on adrenergic innervation. 相似文献
44.
Immunocytochemical localization of casein kinase II during interphase and mitosis 总被引:15,自引:1,他引:14
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We have developed specific antibodies to synthetic peptide antigens that react with the individual subunits of casein kinase II (CKII). Using these antibodies, we studied the localization of CKII in asynchronous HeLa cells by immunofluorescence and immunoelectron microscopy. Further studies were done on HeLa cells arrested at the G1/S transition by hydroxyurea treatment. Our results indicate that the CKII alpha and beta subunits are localized in the cytoplasm during interphase and are distributed throughout the cell during mitosis. Further electron microscopic investigation revealed that CKII alpha subunit is associated with spindle fibers during metaphase and anaphase. In contrast, the CKII alpha' subunit is localized in the nucleus during G1 and in the cytoplasm during S. Taken together, our results suggest that CKII may play significant roles in cell division control by shifting its localization between the cytoplasm and nucleus. 相似文献
45.
46.
Steroidal saponins from Smilax lebrunii. 总被引:5,自引:0,他引:5
Two new steroidal saponins, (25 R)-spirostan-3 beta-ol-6-one-3-O-[alpha-L-arabinopyranosyl (1----6)]-beta-D-glucopyranoside and (25 R)-spirostan-3 beta-ol-6-one-3-O-[beta-D-glucopyranosyl(1---4)] [alpha-L-arabinopyranosyl(1----6)]-beta-glucopyranoside, were isolated from the rhizomes of Smilax lebrunii. Their structures have been established by chemical and spectral methods. 相似文献
47.
Genetic and biochemical approaches have contributed to an explosion of literature on cell-cycle control. Regulation of the cell-cycle is controlled by a series of kinases and phosphatases. Key control points are during the G(1)-S and G(2)-M transitions. During both transitions, cyclins interact with a specific kinase to allow a cell to pass through that phase. The meiotic maturation of oocytes, fertilization and embryo development are all events influenced by cell-cycle regulation. Understanding cell-cycle control should provide new ways for gamete and embryo biologists to approach culture and development problems. 相似文献
48.
49.
Idiotypic analysis of anti-GAT antibodies. VII. Common idiotype on hybridoma antibodies to poly(Glu60 Ala40) 总被引:4,自引:0,他引:4
S T Ju M Pierres R N Germain B Benacerraf M E Dorf 《Journal of immunology (Baltimore, Md. : 1950)》1980,125(3):1230-1236
A single DBA/2 mouse, immunized with L-glutamic acid60-L-alanine40 (GA), was used to produce hybridoma cell lines. Seven hybridoma anti-GA antibodies were obtained for idiotypic analyses. Two hybridoma anti-L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT) antibodies, preferentially reactive to GA, were studied in parallel. Anti-idiotypic antisera to purified anti-GAT and anti-GA serum antibodies and to hybridoma anti-GA antibodies were analyzed by idiotype binding and inhibition of idiotype binding assays. Five of the nine hybridoma antibodies exhibited common GA-1 idiotypic specificities previously demonstrated on the majority of anti-GA antibodies of inbred mouse strains of differing immunoglobulin heavy chain linkage groups; these hybridoma antibodies also possessed private idiotypic determinants. Two GA-1 negative hybridoma anti-GA antibodies appeared identical by immunochemical criteria, arguing that somatic hybridization does not artifactually generate private idiotypic determinants. The results demonstrate that the common GA-1 idiotype system is associated with a family of nonidentical but idiotypically related antibody molecules present in a single DBA/2 mouse, and these antibodies are part of the "GA-1 idiotypic family". 相似文献
50.
The processes of photosynthesis, chemosynthesis and sulphate reduction were quantitatively studied in the brackish meromitic lake Faro (Sicily) with the aid of C14 and S35. The layer of “red water” was situated at the depht of the chemocline (13–14 m), where the average concentration of H2S was 10 mg/l. The total biomass of bacterioplankton consisted in this layer mostly of a brown Chlorobium which reached a wet weight of 30 g/m3. The production of photosynthesis in this layer was 30–60 µg C/l/day. The microbial population in the “red water” was found adapted to an extremely low light intensity and to show a light optimum at the depth µg 9m where only 2,5% of outside light penetrates. The photoautotrophic microflora is consumed by infusoria found in mass in the “red water” layer. An active H2S-production was found in the water column in the upper part of the H2S-zone and in the bottom sediments. The data are discussed from the view point of the trophology of meromitic basins. 相似文献