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101.
Genetic alterations of the tumour suppressor gene regions 3p, 11p, 13q, 17p, and 17q in human breast carcinomas. 总被引:5,自引:0,他引:5
Tone I. Andersen Astrid Gaustad Anne-Lise Brresen George W. Farrants Jahn M. Nesland Lars Ottestad Kjell M. Tveit 《Genes, chromosomes & cancer》1992,4(2):113-121
Fifty-nine primary breast carcinomas and 11 metastases were examined to identify genetic alterations in the tumour suppressor gene regions 3p, 11p, 13q, 17p, and 17q. Loss of heterozygosity (LOH) was frequently observed on chromosome arms 17p (p144D6 lost in 75%, pYNZ22.1 in 55%, and TP53 in 48% of the primary tumours), 13q (RBI lost in 40% of the primary tumours), and 17q (pRMU3 lost in 35%, pTHH59 in 29%, and NM23HI in 26% of the primary tumours). Loss of all the markers except p144D6 was observed even more frequently in the metastases. Pairwise comparisons for concordance of allele losses on 17p indicated that there might be two genes on 17p implicated in breast cancer development; the TP53 gene and a gene located close to the p144D6 and pYNZ22.1 markers. LOH of the RBI gene was associated with LOH of pYNZ22.1 and p144D6, but not with LOH of TP53. LOH of RBI and TP53 was associated with occurrence of ductal carcinomas, RBI and p144D6 losses with tumour size, and p144D6 losses with positive node status as well. LOH of TP53 and the three 17q markers NM23HI, pTHH59, and pRMU3 was most frequently observed in tumours from postmenopausal women. p144D6 losses occurred most frequently in progesterone receptor-negative tumours, whereas pTHH59 losses occurred most frequently in oestrogen receptor-negative tumours. LOH of the investigated loci was not associated with ERBB2 protooncogene amplification, with positive family history of breast cancer, or with survival. 相似文献
102.
Recovery of mice from herpes simplex virus type 2 hepatitis: adoptive transfer of recovery with immune spleen cells. 总被引:2,自引:1,他引:2
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Young BALB/c mice inoculated intraperitoneally with herpes simplex virus type 2 develop focal necrotizing hepatitis. After infection, the livers of these mice show increasing virus titers, which reach a maximum on day 3 after infection; this is followed by a dramatic decrease in the amount of virus recovered on days 4 and 5. This decrease in virus content is accompanied by a progressive infiltration of the lesions with mononuclear leukocytes and an apparent resolution of the lesions. Adoptive transfer of immune spleen cells from mice infected 6 days earlier accelerated this process. When 50 x 10(6) to 100 x 10(6) immune spleen cells were transferred 24 h after infection, the inflammatory response and the clearance of virus from the livers were advanced by almost 2 days. As few as 12 x 10(6) immune spleen cells accelerated the healing process, whereas fewer immune cells, disrupted immune cells, or normal spleen cells did not have an effect. The protection conferred by herpes simplex virus type 2-sensitized immune spleen cells was specific since mouse cytomegalovirus- or vaccinia virus-sensitized immune spleen cells had no effect on the course of infection with herpes simplex virus type 2, whereas some cross-reactivity was observed between herpes simplex virus types 1 and 2. This model seems to be suitable for examining the immunological mechanisms that are active during recovery from visceral herpes simplex virus infections. 相似文献
103.
Time interval from human chorionic gonadotrophin (HCG) injection to follicular rupture 总被引:1,自引:1,他引:1
Andersen A.G.; Als-Nielsen B.; Hornnes P.J.; Andersen L.Franch 《Human reproduction (Oxford, England)》1995,10(12):3202-3205
The aim of this study was to estimate the time interval fromhuman chorionic gonadotrophin (HCG) injection to follicularrupture. Furthermore, it was observed whether there was anyeffect on the pregnancy rate if the insemination was performedat the time of follicular rupture. In a programme of intrauterineinsemination 37 consecutive cycles in 32 patients were monitoredafter stimulation with clomiphene citrate. HCG was administeredby i.m. injection when a leading follicle of at least 18 mmin diameter was observed sonographically. All patients weremonitored by sonography with 1 h intervals from 32 h after HCGinjection until the first rupture of a follicle. Inseminationwas performed immediately after the first follicular rupture.The pregnancy rate was 16% (5/32). In 66%, the largest folliclewas the first to rupture. The mean time interval from HCG administrationto first follicular rupture was 38.3 h (SEM = 0.54; range =3416). Our findings support the concept that ovulationoccurs about 38 h after HCG administration. The pregnancy ratewas within the normal range, although insemination was performedat the time of follicular rupture. The largest follicle wasnot always the first to rupture 相似文献
104.
H T Andersen E B Smeland J O Owe K Myhre 《Aviation, space, and environmental medicine》1985,56(12):1192-1197
The maximum cardiopulmonary performance of seven healthy male subjects was studied repeatedly in graded hypoxia at ambient pressures ranging from 760 to 404 mm Hg (sea level to 5000 m of simulated altitude). Using this approach it has been possible to not only establish a reproducible value for VO2max, but to determine an equation which may be used to predict the VO2 at altitude for healthy, unacclimatized males exercising to exhaustion. Moreover, we have attempted to explain the limits to pulmonary ventilation at decreasing levels of PO2 by comparing a given VO2max (STPD) to the corresponding VEmax (BTPS), showing that any further increase in the latter is impossible when a certain level of altitude has been reached. Finally, our series of experiments indicates that the HRmax falls at altitude. Although statistically significant, this decrement is not conspicuous. Thus, when used with the VO2max to calculate the number of ml of O2 consumed per beat of the heart, the "oxygen pulse" turns out to be more sensitive to the fall in VO2max at altitude than to the corresponding decrease in the HRmax. 相似文献
105.
Eighth young adult male volunteers with a basic (alimentary) plasma boric acid concentration of <0.10–0.46 mg/l were given a single dose of boric acid (562–611 mg) by 20 min IV infusion. The plasma concentration curves, followed for 3 days, best fitted a three-compartment open model, although two subjects had to be left out due to inconstant basal plasma concentration values or failure to fit to the three-compartment model. The 120 h urinary excretion was 98.7±9.1% of dose, Cltot 54.6±8.0 ml/min/1.73 m2, t1/2 21.0±4.9 h and distribution volumes V1, V2, and V3: 0.251±0.099, 0.456±0.067 and 0.340±0.128 l/kg. 相似文献
106.
107.
Andersen Patrick Mizdrak Anja Wilson Nick Davies Anna Bablani Laxman Blakely Tony 《Population health metrics》2022,20(1):1-12
The mortality pattern from birth to age five is known to vary by underlying cause of mortality, which has been documented in multiple instances. Many countries without high functioning vital registration systems could benefit from estimates of age- and cause-specific mortality to inform health programming, however, to date the causes of under-five death have only been described for broad age categories such as for neonates (0–27 days), infants (0–11 months), and children age 12–59 months. We adapt the log quadratic model to mortality patterns for children under five to all-cause child mortality and then to age- and cause-specific mortality (U5ACSM). We apply these methods to empirical sample registration system mortality data in China from 1996 to 2015. Based on these empirical data, we simulate probabilities of mortality in the case when the true relationships between age and mortality by cause are known. We estimate U5ACSM within 0.1–0.7 deaths per 1000 livebirths in hold out strata for life tables constructed from the China sample registration system, representing considerable improvement compared to an error of 1.2 per 1000 livebirths using a standard approach. This improved prediction error for U5ACSM is consistently demonstrated for all-cause as well as pneumonia- and injury-specific mortality. We also consistently identified cause-specific mortality patterns in simulated mortality scenarios. The log quadratic model is a significant improvement over the standard approach for deriving U5ACSM based on both simulation and empirical results. 相似文献
108.
109.
Per Kragh Andersen Maja Pohar Perme Hans C. van Houwelingen Richard J. Cook Pierre Joly Torben Martinussen Jeremy M. G. Taylor Michal Abrahamowicz Terry M. Therneau 《Statistics in medicine》2021,40(1):185-211
This paper provides guidance for researchers with some mathematical background on the conduct of time‐to‐event analysis in observational studies based on intensity (hazard) models. Discussions of basic concepts like time axis, event definition and censoring are given. Hazard models are introduced, with special emphasis on the Cox proportional hazards regression model. We provide check lists that may be useful both when fitting the model and assessing its goodness of fit and when interpreting the results. Special attention is paid to how to avoid problems with immortal time bias by introducing time‐dependent covariates. We discuss prediction based on hazard models and difficulties when attempting to draw proper causal conclusions from such models. Finally, we present a series of examples where the methods and check lists are exemplified. Computational details and implementation using the freely available R software are documented in Supplementary Material. The paper was prepared as part of the STRATOS initiative. 相似文献
110.