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41.
Field cultivation experiments on white sesame (Sesamum indicum L.)seeds implanted with low-energy C ion showed that different dosages of C ion implantation produce different biological effects.Sesame plants in 6 different dosage groups with C ion density respectively at 1×1011,1×1012,1×1015,5×1015,1×1016,5×1016 ion/cm2 were superior to the control group in plant height,leaf number,stalk diameter and leaf size.Further,sesame plants in these groups flower and seed earlier than those in the control group,and single plant yield also increased.Of all the groups,the 5×1015 ion/cm2 dosage group yielded the best effect,whereas the 1×1017/cm2 dosage group showed an evident inhibitory effect of ion implantation on the germination and growth of the sesame seeds. 相似文献
42.
L. M. Mezhevikina I. V. Kapralova E. E. Fesenko 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2007,1(2):164-167
The effect of recombinant LIF cytokine (Leukemia inhibitory factor) on the isolated mouse embryos at the stages of middle and late blastocyst has been investigated. We have demonstrated here that this agent is necessary in vitro at the stage of normal trophoblast formation after the blastocysts hatch from zona pellucida. This cytokine (10 ng/ml) caused intensification of adhesion and proliferative activity of the trophoblast cells. This is important for intercellular interactions with endometrium and for invasion of embryos into the uterus. The recombinant LIF insignificantly influenced cells of the inner cell mass. 相似文献
43.
目的:调查冠状动脉支架植入(ICS)患者心理弹性状况,并分析心理弹性与生活质量的关系。方法:选取2019年3月~2021年4月我院收治的ICS患者120例作为观察组,另选取同期来我院进行健康体检的志愿者80例作为对照组,对比两组患者的生活质量评分,以心理弹性量表(CD-RICS)调查ICS患者的心理弹性状况,采用Pearson相关分析ICS患者生活质量与心理弹性的相关性,采用Logistic回归分析ICS患者心理弹性水平的影响因素。结果:观察组36条目健康调查简表(SF-36)各维度评分及总评分均低于对照组(P<0.05)。120例ICS患者的心理弹性总分为(64.41±5.73)分,心理弹性各维度得分由低到高分别为乐观、力量、坚韧。Pearson相关分析结果表明,ICS患者的生活质量平均分与心理弹性总分呈正相关(P<0.05)。冠心病病程、文化程度、家庭月收入、兴趣爱好数量、居住地对ICS患者的心理弹性得分有影响(P<0.05)。冠心病患病时间≥10年、文化程度为初中及其以下、家庭月收入≤3000元、兴趣爱好为1~2个、居住地为农村是ICS患者心理弹性水平的影响因素(P<0.05)。结论:ICS患者的心理弹性水平一般,且可影响患者生活质量,受到冠心病病程时长、文化程度、家庭收入水平、兴趣爱好、居住地等多种因素影响,应制定合理措施来提高ICS患者的心理弹性,促进患者身心健康。 相似文献
44.
Naser Shokrzadeh Mohammad Reza Alivand Ali Abedelahi Mohammad B. Hessam Shariati Behrooz Niknafs 《Journal of cellular physiology》2019,234(8):12989-13000
Calcitonin (CT) is one of the factors affecting the embryo implantation, but its effects on the implantation window have not been fully investigated. The current study investigated the effects of CT on the endometrium receptivity by morphological study and evaluation of leukemia inhibitory factor (LIF), mucin 1 (Muc-1), and microRNA (miRNA) Let-7a in the ovarian stimulation and the normal ovarian cycle. Then the mechanism of the CT effects through the mammalian target of rapamycin (mTOR) signaling pathway was studied by using PP242. A total of 64 BALB/c mice were divided into the normal ovarian cycle and ovarian stimulation groups. Each group consisted of four subgroups: control, calcitonin, PP242, and calcitonin+PP242. CT and PP242 were injected on the fourth of pregnancy into the mice and 24 hr later all the mice were killed. The uterine tissue samples were used for morphological analysis, and endometrial cells were mechanically isolated for evaluation of gene and protein expression. The results showed that ovarian stimulation induced mTOR phosphorylation as well as increased expression of the Let-7a miRNA. In addition, CT injection increased the expression of LIF and miRNA Let-7a in ovarian stimulation similar to that in normal ovarian cycles. However, injection of PP242 reduced expression of miRNA Let-7a and increased Muc-1 expression in ovarian stimulation group. In conclusion, the administration of CT improved endometrial receptivity in mice. This phenomenon occurred by upregulation of LIF, miRNA Let-7a and downregulation of Muc-1 via mTOR signaling pathway. 相似文献
45.
Transcriptome analysis of the endometrium from Chinese Erhualian sows that differ in calcium ion concentration and litter size 总被引:1,自引:0,他引:1
X. Ma P. Li Q. Zhang L. He G. Su Y. Huang Z. Lu W. Hu H. Ding R. Huang 《Animal genetics》2019,50(4):326-333
Embryonic survival rate, an important factor in the fecundity of sows, is affected by endometrium‐secreting histotroph. A higher concentration of calcium ion has been observed in the uterus of highly prolific Erhualian sows (EH) compared with those of less prolific (EL) sows. This suggests that EH sows have better establishment and maintenance of pregnancies, thus increasing embryonic survival rate during the peri‐implantation period. To understand the mechanisms of how the endometrium‐secreting histotroph affects embryonic survival rate during the Erhualian peri‐implantation period, the expression patterns of endometrial mRNA in the EH and EL sows on day 12 of gestation were analyzed using RNA sequencing technology. A total of 164 differentially expressed genes (DEGs) were identified (Padj < 0.05, |log2(FC)| ≥ 1), including 46 upregulated and 118 downregulated genes in EH compared to EL. Gene Ontology enrichment indicated that a subset of DEGs was involved in calcium ion binding and cell adhesion. Solute carrier family 8 member A3 and solute carrier family 24 member 4, identified as upregulated genes (Padj < 0.05) in EH, were considered key candidate genes expressed in the endometrium affecting embryonic survival rate during the peri‐implantation period. The results improve understanding of the genetic mechanism underlying the variation in litter size of Erhualian pigs during the peri‐implantation period. 相似文献
46.
47.
Hayashi T Yamagishi A Kuroiwa A Mizuno N Kondoh H Okamoto M 《Development, growth & differentiation》2001,43(4):361-370
The analysis of newt lens regeneration has been an important subject in developmental biology. Recently, it has been reported that the genes involved in the normal eye development are also expressed in the regenerative process of lens regeneration in the adult newt. However, functional analysis of these genes has not been possible, because there is no system to introduce genes efficiently into the cells involved in the regeneration. In the present study, lipofection was used as the method for gene transfer in cultured pigmented iris cells that can transdifferentiate into lens cells in newt lens regeneration. Positive expression of a reporter gene was obtained in more than 70% of cells. In addition, the aggregate derived from gene-transfected cells maintained its expression at a high level for a long time within the host tissue. To verify the effectiveness of this model system with a reporter gene in lens regeneration, Pax6, which is suggested to be involved in normal eye development and lens regeneration, was transfected. Ectopic expression of lens-specific crystallins was obtained in cells that show no such activity in normal lens regeneration. These results made it possible for the first time to analyze the molecular mechanism of lens regeneration in the adult newt. 相似文献
48.
Ezrin and radixin and protein 4.1 were detected in the lens of the eye. These proteins were mainly present in the young elongating cortical fiber cells and localized to the plasma membranes. Moesin was not detected. Ezrin, radixin, and protein 4.1 provide another means whereby actin is linked to the plasma membrane in addition to the known adherens junctions in the lens. 相似文献
49.
Didone?FrigerioEmail author Katharina?Hirschenhauser Erich?M?stl John?Dittami Kurt?Kotrschal 《Acta ethologica》2004,7(1):9-18
Testosterone modulates male vertebrates sexual and social behaviour. We experimentally investigated the testosterone-sensitive behaviours in male greylag geese (Anser anser) by implanting silastic tubes containing crystalline testosterone during the mating season (February; 5 implanted and 5 control males) and in the early winter (November; 7 and 7). Focal animals were part of a semi-tame, unrestrained flock with fully intact social relationships. Excreted testosterone and corticosterone immunoreactive metabolites (TM, BM) were determined by enzyme immunoassay. Individual faecal samples and behavioural protocols were collected daily over a period of 5 weeks, including 1 control week before implantation. In February, no significant behavioural effects of the supplemental testosterone were observed, which may be due to the naturally occurring high systemic androgen levels in spring. In November, however, implanted males had higher TM excretion rates and performed status signalling behaviour (beak up) more frequently than control males. No differences between implanted and control males were found with respect to BM, agonistic interactions or vigilance behaviour. Furthermore, during the second week after implantation, TM positively correlated with the frequency of beak up of implanted males, whilst their female partners were attacked with lower latency by other members of the flock than the females of control males. Hence, status signalling in greylag ganders seems to be testosterone-sensitive year-long and inappropriate status signalling of males may draw attacks towards their females. 相似文献
50.
Mutation of Gluconobacter oxydans and Bacillus megaterium in a two-step process of l-ascorbic acid manufacture by ion beam 总被引:5,自引:0,他引:5
AIM: To increase the transformation rate of l-sorbose to 2-keto-l-gulonic (2-KLG) acid in a two-step process of l-ascrobic acid manufacture by ion beam. METHODS AND RESULTS: Gluconobacter oxydans (GO29) and Bacillus megaterium (BM80) were used in the present study. Ion implantation was carried out with the heavy ion implantation facility at the institute of Plasma Physics in China. 2-KLG in whole culture broth was determined by iodometry. Mutants were screened by single-colony isolation and 2-KLG accumulation in broth. GO29 and BM80 were implanted by either hydrogen ions (H(+)) or nitrogen ions (N(+)) with various doses, respectively. The average transformation rate of GM112-302 bred by ion beam in Gram-molecule was increased from 79.3 to 94.5% after eight passages in shaking flasks. Furthermore, in 180-ton fermentors in Jiangsu Jiangshan Pharmaceutical Co. Ltd, the transformation rate was stable at 92.0%, indicating a producer could get 0.99 kg of gulonic acid from 1.0 kg of sorbose. CONCLUSION: Ion beam as a new mutation source had potential advantages in breeding. Comparing with original mixture GO29 and BM80, GM112-302 is more efficient in accumulating 2-KLG, especially at the later phase. SIGNIFICANCE AND IMPACT OF THE STUDY: GM112-302 bred by ion beam implantation dramatically increased the transformation rate by 19.2%, which greatly increased efficiency and reduced the cost of l-ascorbic acid manufacture in a two-step process. 相似文献