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301.
Incidence of diploid and disomic sperm nuclei in 45 infertile men 总被引:16,自引:13,他引:3
Guttenbach M; Martinez-Exposito MJ; Michelmann HW; Engel W; Schmid M 《Human reproduction (Oxford, England)》1997,12(3):468-473
Sperm cells from 45 infertile patients were investigated for disomy rates
of chromosomes 1, 7, 10, 17, X and Y as well as for diploidy by single- and
double-target in-situ hybridization. The patients who attended the
infertility clinic were aged 23-46 years. Semenograms showed that the
patients had oligo-, astheno-, oligoastheno-, oligoterato-,
oligoasthenoterato-, or asthenoteratozoospermia. The average disomy rates
determined in the patients were similar for all chromosomes, ranging from
0.10% (chromosome Y) to 0.14% (chromosomes 10 and X). Diploidy was detected
with a mean incidence of 0.1%. With the exception of two patients who
exhibited significantly increased diploidy rates of 0.35 and 1.6%, neither
disomy nor diploidy was increased in the group of infertile patients as
compared to healthy, fertile males.
相似文献
302.
丹参酮及有关成分的质谱与高效薄层鉴定 总被引:5,自引:0,他引:5
从丹参Salvia miltiorrhiza Bunge及甘西鼠尾草Salvia przewalskii Maxim中分离得到28个萜类化合物,分别给出它们在6种溶剂系统中的比移值及其质谱数据、主要碎片及特征离子峰。为鉴定该属植物化学成分提供依据。 相似文献
303.
The bromodeoxyuridine (BrdU)-Hoechst flow cytometric technique was applied to study the immediate cell kinetic response of highly purified human (h) bone marrow progenitor cells (CD(34+)-sorted fraction) to h granulocyte colony-stimulating factor (G-CSF) and/or h granulocyte- macrophage colony-stimulating factor (GM-CSF). The technique permits us to differentiate cycling from noncycling cells and to make a quantitative assessment of cell cycles after stimulation. Semisolid agar and single-cell liquid cultures were also performed to compare these initial events to the effects observed after 14 days of culture. The combination of G-CSF plus GM-CSF, acting synergistically in day 14 cultures, was found to have a subadditive effect in the first cell cycles, thereby indicating partial overlap of the different target cells. However, this combination accelerated transit through the cell cycle, as could be seen from the higher number of cells in the third cell cycle after 72 hours of stimulation. We conclude that, apart from the unresponsive cells, the CD34+ compartment consists of cells responsive to both G-CSF and GM-CSF, and cells responsive to either one of the CSFs alone, and that the combination of the two CSFs speeds up the cell cycle traverse rate for a significant fraction of the target cells that are initially responsive for both G-CSF and GM-CSF. The latter supports the hypothesis of an overlapping signalling pathway of G-CSF and GM-CSF. 相似文献
304.
305.
G. Ralph W. Lichtenegger M. Lahousen H. Auner K. Tamussino 《Archives of gynecology and obstetrics》1987,242(1-4):431-432
Ohne Zusammenfassung 相似文献
306.
307.
Jiang WZ Jin NY Li ZJ Zhang LS Wang HW Zhang YJ Han WY 《第二军医大学学报》2005,26(11):1259-1259
To express the core protein of HIV-1 of Chinese prevalent strata (HIV-1[CN]) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sal I was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kDa, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13% of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80%-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85%. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting. 相似文献
308.
中药玉竹有效成分研究 总被引:30,自引:0,他引:30
自江苏海门产百合科植物玉竹[Polygonatum odoratum(Mill.)Druce]根茎的乙醇提取物中分得六个单体化合物,根据化学性质和光谱解析,鉴定其化学结构分别为β-谷甾醇(S-A)),β-谷甾醇-3-O-β-D-吡喃葡萄糖甙(S-B),25(R,S)螺甾-5-烯-3β-醇-3-O-β-D-吡喃葡萄糖基-(1→2)-[β-D-吡喃木糖基-(1→3)]-β-D-吡喃葡萄糖基(1→4)-β-吡喃半乳糖甙(POD-I),25(R)螺甾-5-烯-3β,14a-二醇-3-0-β-D-吡喃葡萄糖基-(1→2)-[β-D-吡喃木糖基-(1→3)]-β-D-吡喃葡萄糖基-(1→4)-β-D-吡喃半乳糖甙(POD-II),25(R,S)螺甾-5-烯-3β,14a-二醇-3-O-β-D-吡喃葡萄糖基-(1→2)-[β-D-吡喃葡萄糖基-(1→3)]-β-D-吡喃葡萄糖基(1→4)-β-D-吡喃半乳糖甙(POD-III)和25(R,S)螺甾-5-烯-3β-醇-3-O-β-D-吡喃葡萄糖基-(1-2)-[β-D-吡喃葡萄糖基-(1→3)]-β-D-吡喃哺葡萄糖基(1→4)-β-D-吡喃半乳糖甙(POD-IV)。POD-II为首次分离得到的25(R)构型的纯品,POD-III和POD-IV为首次从玉竹中得到。经初步药理实验显示,POD-II有诱生集落刺激因子(CSF)的作用,POD-III能协同ConA和Lps对淋巴细胞转化有促进作用。 相似文献
309.
RA Spence GW Johnston GW Odling-Smee HW Rodgers 《Archives of disease in childhood》1984,59(4):336-340
Complete long term follow up was obtained in 27 children who had bled from oesophageal varices. Most presented with haematemesis or melaena at an average age of 5.2 years in the portal vein thrombosis group (20 children) and 9.5 years in the intrahepatic group (7 children). All had splenomegaly. Only 6 of 20 children with portal vein thrombosis had a possible precipitating factor. A total of 182 admissions for bleeding are reported, in 68 of which injection sclerotherapy was used to control bleeding. Control rate with injection sclerotherapy was 97%. Shunts performed below age 10 years were associated with a high thrombosis rate. A conservative approach to bleeding varices in children is recommended with transfusion, pitressin, and injection sclerotherapy. Oesophageal transection may have a role in the emergency management of the few children in whom bleeding is not controlled by injection sclerotherapy. 相似文献
310.
Multiple trauma in children is rare so that even large trauma centers will only treat a small number of cases. Nevertheless, accidents are the most common cause of death in childhood whereby the causes are mostly traffic accidents and falls. Head trauma is the most common form of injury and the degree of severity is mostly decisive for the prognosis. Knowledge on possible causes of injury and injury patterns as well as consideration of anatomical and physiological characteristics are of great importance for treatment. The differences compared to adults are greater the younger the child is. Decompression and stopping bleeding are the main priorities before surgical fracture stabilization. The treatment of a severely injured child should be carried out by an interdisciplinary team in an approved trauma center with expertise in pediatrics. An inadequate primary assessment involves a high risk of early mortality. On the other hand children have a better prognosis than adults with comparable injuries. 相似文献