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The proliferative activity of human pulmonary carcinoma cells has been examined by autoradiography in 48 cultures in diffuse chambers, incubated with 3H thymidine under various conditions. 3H thymidine has been injected intraperitoneally to one group of animals, in another group the diffuse chambers have been removed from the animals and incubated in culture medium with 3H thymidine in the same concentration. The proliferation intensity of the cell cultures from the same patients has been virtually the same in both modes of incubation. This permits simplifying the autoradiography technique for such experiments, thus helping to avoid the difficulties connected with radioactive waste utilization. 相似文献
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Alexandr G. Potapov Vladimir A. Zakharov Tatijana B. Mikenas Sergeyi A. Sergeev Alexandr M. Volodin 《Macromolecular chemistry and physics.》1997,198(9):2867-2873
ESR was used for studying the interaction between the stable nitroxyl radical TEMPO (2,2,6,6-tetramethylpyperidin-1-oxyl) and the titanium-magnesium catalysts TiCl4/MgCl2 and TiCl4/MgCl2 · nD (D is either diisobutyl phthalate or 2,2-diisobutyl-1,3-dimethoxypropane), as well as TiCl4/MgCl2 · nD treated with triethylaluminium. In all cases, only part of the surface titanium complexes (18–53 mol-%) exhibit Lewis acid properties and can interact with TEMPO. The portion of titanium complexes with acidic properties depends on the composition and preparation of the catalysts, and it decreases upon treatment with triethylaluminium. 相似文献
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Donor insemination: Dutch parents' opinions about confidentiality and donor anonymity and the emotional adjustment of their children 总被引:1,自引:4,他引:1
Brewaeys A; Golombok S; Naaktgeboren N; de Bruyn JK; van Hall EV 《Human reproduction (Oxford, England)》1997,12(7):1591-1597
Results from a comparative study investigating 38 donor insemination (DI)
Dutch families with 4-8 year old children are presented. The aims of this
study were to investigate parents' opinions on the issues of
confidentiality and donor anonymity, to assess the emotional development of
the children, and to examine in DI families the association between secrecy
with regard to the use of a donor and the emotional adjustment of the
children. The DI families were compared to families with a child conceived
by in-vitro fertilization (IVF) and to families with a naturally conceived
child. Secrecy appeared to be associated with DI and not with IVF: 74% of
the DI parents intended not to inform the child about the way in which
she/he was conceived, whereas none of the IVF parents intended to keep the
secret. Only one set of DI parents and two sets of IVF parents had actually
told the child. As to donor anonymity, a spread of opinions appeared among
DI parents; 57% preferred an anonymous donor, 31% would have liked non-
identifying information about the donor, 9% preferred the donor's identity
to be registered and 3% remained unsure. Parents' major concern was to know
more about the medical/genetic background of the donor. Mothers and fathers
in the DI families differed in their opinions concerning the issues of
confidentiality and donor anonymity: fathers, more often than mothers, were
secretive with regard to the use of a donor and husbands, more often than
their wives, were in favour of donor anonymity. With regard to the
emotional development of the children, more emotional/behavioural problems
were revealed among DI children than among children who were naturally
conceived. No association was found between secrecy and the
emotional/behavioural adjustment of the children.
相似文献
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BACKGROUND: The continual shortage of hearts for transplantation (HTx) led to the expansion of the donor pool by accepting older donors. We compared the medium-term follow-up of patients after HTx with older hearts (over the age of 63 years) with those of patients after HTx with younger hearts. PATIENTS AND METHODS: Since April 1994 we have used hearts for HTx from donors older than the age of 63 years. Until November 1998, 309 HTx and 9 re-HTx were performed in 309 adults with a mean age of 50.7+/-10.9 years (range 17-68 years). There were 252 men and 57 women. The patients were divided into two groups: group I--donor age under 63 years (296 patients, mean age 50.4+/-11 years; mean donor age 38.1+/-13 years; mean follow-up 1.7+/-1.6 years); group II-donor age of more than 63 years (13 patients, mean age 57.4+/-5.6 years; mean donor age 65.1+/-2.1; mean follow-up 2.2+/-1.6 years). There were no differences in the etiology of heart failure, gender, or ischemia time between the groups. The patients in group II were significantly older (P = 0.008). Multiple factors were analyzed in the groups, which included changes in the left/right ventricle ejection fraction, early postoperative mortality (up to 30 days), cumulative survival rates and cardiac-dependent morbidity [myocardial infarction, malignant arrhythmias, coronary stenosis (>50% in one of the main coronary arteries) and transplant vasculopathy]. Additionally, freedom from cytomegalovirus infection (rise of titer or seroconversion) and freedom of acute rejection episodes grade > or =2 (International Society of Heart & Lung Transplantation [ISHLT]) were analyzed. RESULTS: After 1 year mean left and right ventricle ejection fraction were good in both groups and did not significantly change for up to 2 years. No Re-HTx was performed in group II. The early postoperative mortality was similar in both groups (P = 0.8). Also, the cumulative survival rates were similar in both groups (P = 0.87). Long-term cardiac morbidity was lower in group I (P = 0.03). The long-term freedom from cytomegalovirus infection in group I was significantly higher when compared with group II (P = 0.0002). The long-term freedom from severe rejection episodes was similar in both groups (P = 0.3) CONCLUSION: The study found a significant increase in long-term cardiac morbidity due to more focal coronary stenosis in group II, and freedom from cytomegalovirus infection, but did not find significant differences in the long-term survival between patients who received hearts from donors of up to 63 years of age and from those more than 63 years. The acceptance of donors older than 63 years old for HTx does not worsen the outcome of the recipients. The careful selection of older donors, with close monitoring of the coronary situation after HTx and expanded indications for revascularization of older hearts, could make HTx with older hearts, even in older recipients, a safe option. 相似文献
10.
Potapov AL 《Klinichna khirurhiia / Ministerstvo okhorony zdorov'ia Ukra?ny, Naukove tovarystvo khirurhiv Ukra?ny》2000,(9):29-31
There were examined the surface-active properties and phospholipidious contents of the breathed out air condensate and the general respiratory compliance (C) in 21 patients with an acute pulmonary damage syndrome (APDS), caused by pancreonecrosis, peritonitis, polytrauma, sepsis. The lowering of the surface activity, reducing of phosphatidylcholine content and raising of phosphatidylethanolamine level, significant C lowering were noted. Such changes were more pronounced in patients, which have died subsequently. This testifies the profound inhibition of the pulmonary surfactant system activity in patients with APDS. It is expedient to apply the exogenic surfactant preparations for the treatment of patients with APDS. 相似文献