Visual search for singleton feature targets within and across feature dimensions.

Three experiments investigated visual search for singleton feature targets. The critical dimension on which the target differed from the nontargets was either known in advance or unknown--that is, the critical difference varied either within a dimension or across dimensions. Previous work (Treisman, 1988) had shown that, while the search reaction time (RT) functions were flat in both conditions, there was an intercept cost for the cross-dimension condition.

Genetic and environmental influences on blood pressure in elderly twins.

We used 289 pairs of Swedish twins reared apart or together to evaluate the importance of genetic and environmental influences on blood pressure. Unlike other twin and family studies, the adoption/twin design allows a distinction between estimates of the importance of shared rearing environments and genetic effects. Genetic factors were observed to play an important role for individual differences in blood pressure.

Genetic and environmental correlations among serum lipids and apolipoproteins in elderly twins reared together and apart.

Genetic and environmental correlations among five serum-lipid measures were examined in the Swedish Adoption/Twin Study of Aging. The sample included 302 twin pairs; 146 of these twin pairs were separated at an early age and were reared apart. The lipid measures examined include total cholesterol, HDL-cholesterol, triglycerides, and apolipoproteins A-I and B.

Vulvar and vaginal melanoma. A clinicopathologic study.

Melanoma of the vulva is uncommon, and melanoma of the vagina is rare. The overall prognosis is poor and worse than for cutaneous melanomas. This appears to relate to diagnosis of genital lesions at an advanced stage.

Cystinosis and gingival hyperplasia: demonstration of cystine crystals in gingival tissue and unusual aspects of management.

A patient with nephropathic cystinosis developed gingival hyperplasia secondary to cyclosporine-A therapy for his renal allograft. The typical crystals described on electron microscopic examination of other organs of patients with cystinosis were seen in the resected gingiva of this patient. These crystals have not been previously described in this location.

Genetic and environmental influences on pulmonary function in aging Swedish twins.

Background: In addition to their value in assessing pulmonary health and disease, spirometric variables have been shown to be powerful predictors of time until death in aging populations. The sources of variability in these spirometric values are consequently of relevance to basic gerontological research, and also of potential value in clinical application. The objective of this study was to estimate genetic and environmental sources of variance in pulmonary function.

The kinetics of cellular recovery in exponential and plateau growth phase human glioma cells following gamma-irradiation.

Purpose: In this study the kinetics of recovery following irradiation was examined in a human glioma cell line. Specific objectives were: to determine whether recovery is mono- or biexponential in nature; to determine if recovery half-times are different in exponential and plateau growth phase cells; to compare recovery half-times as a function of dose or recovery levels; and finally, to compare the kinetics of sublethal damage recovery and potentially lethal damage recovery in plateau growth phase cells.

Methods And Materials: U-87MG cells were irradiated in exponential and plateau growth phases and then subjected to incubation at 37 degrees C for various periods of time following or between doses prior to assaying for survival.

Confirmation of leucogentian violet in chicken fat by gas chromatography/mass spectrometry.

A gas chromatographic/mass spectrometric (GC/MS) procedure for confirming the identity of leucogentian violet (LGV) in chicken fat was developed for regulatory application. The unused portion of the extract remaining from a determinative procedure was back-extracted into an organic phase, concentrated, and analyzed by GC/MS. Confirmation of the identity of LGV was based on matching the retention times and relative abundances of 6 ions in the extract to corresponding values obtained for the LGV standard.

Inhibition of potentially lethal damage recovery by altered pH, glucose utilization and proliferation in plateau growth phase human glioma cells.

Recovery from potentially lethal damage (PLD) has been measured in plateau growth phase human glioblastoma cells (U-87MG) under four postirradiation medium conditions. Recovery was maximal in depleted medium at an acidic pH, conditions which inhibit cellular proliferation. Compared with this control, PLD recovery (PLDR) was increasingly inhibited by alkalization of the existing medium (to pH 7.

Fluorescence lifetime analysis of DNA intercalated ethidium bromide and quenching by free dye.

The fluorescence characteristics of ethidium bromide (Eb) complexed to calf thymus DNA have been examined using fluorescence lifetime analysis for a range of DNA (effective nucleotide concentration) to Eb molar ratios. Control of both temperature and ion concentration is necessary for reproducible analyses. Eb complexed to double stranded DNA has a maximum fluorescence lifetime of 23 ns and is easily distinguishable from a fluorescence lifetime value of 1.

Comparison of thermoradiosensitization in two human melanoma cell lines and one fibroblast cell line by concurrent mild hyperthermia and low-dose-rate irradiation.

Two human melanoma cell lines, one radioresistant (SK-MEL-3) and one radiosensitive (HT-144), and a normal human fibroblast line (AG1522) were evaluated for thermoradiosensitization of low-dose-rate irradiation by concurrent mild hyperthermia (39-41 degrees C). None of the cell lines expressed chronic thermotolerance during heating at 39-41 degrees C. The SK-MEL-3 cells were the most heat sensitive, while AG1522 and HT-144 cells had the same sensitivity at 39 and 40 degrees C but HT-144 cells were more sensitive at 41 degrees C.

Thermal radiosensitization by 41 degrees C hyperthermia during low dose-rate irradiation in human normal and tumour cell lines.

Three human cell lines (glioma, melanoma and fibroblast) were evaluated for responses to low dose-rate irradiation (LDRI) (0.88 and 0.41 cGy per min) alone or with concurrent heating (41 degrees C) during irradiation.

Immunohistochemical localization of urokinase-type plasminogen activator and the plasminogen activator inhibitors 1 and 2 in early human implantation sites.

Objective: Our purpose was to immunolocalize urokinase-type plasminogen activator and the plasminogen activator inhibitors 1 and 2 in human implantation sites, with emphasis on the types of trophoblast expressing the plasminogen activator and the inhibitors.

Study Design: Urokinase and the plasminogen activator inhibitors 1 and 2 were localized immunohistochemically in early human implantation sites in unruptured ectopic pregnancies from patients in an in vitro fertilization program.

Results: Urokinase kinase and the plasminogen activator inhibitors 1 and 2 were localized in the cytoplasm of cytotrophoblasts and in the cytoplasm and plasma membranes of intermediate and syncytiotrophoblast.

Transvaginal sonographic characterization combined with cytologic evaluation in the diagnosis of ovarian and adnexal cysts.

A transvaginal sonographic (TVS) scoring system using morphologic features has been developed at our institution to maximize discrimination between benign and malignant ovarian and adnexal cysts. Low (4-7) or intermediate (8-9) scores have been found to correlate with benignity, hence TVS-guided or laparoscopically directed needle aspiration of low-scoring lesions may safely be performed. High-scoring lesions (10-14) are often malignant, therefore in situ needle aspiration of such lesions is not recommended.

Comparison of dimethyl dioctadecyl ammonium bromide, Freund's complete adjuvant and mineral oil for induction of humoral antibodies, cellular immunity and resistance to Newcastle disease virus in chickens.

Dimethyl dioctadecyl ammonium bromide (DDA), a lipophilic quaternary amine, was evaluated in adult chickens for potentiation of immunological responses to subcutaneously administered inactivated Newcastle disease virus (NDV) vaccines. DDA enhanced humoral and cell-mediated immune (CMI) responses to levels which were significantly higher than those induced by the vaccine alone The haemagglutination inhibition antibody titers induced by DDA were slightly lower than those induced by mineral oil although neutralizing antibody titers seemed to be higher. DDA induced strong CMI (DTH and lymphocyte proliferation) responses, more than those induced by Freund's complete adjuvant and mineral oil.

Inhibition of potentially lethal damage recovery by cisplatin in a brain tumor cell line.

Radiation resistant tumours such as gliomas show enhanced capacity for potentially lethal damage recovery (PLDR), which can be inhibited by cisplatin. The 9L rat brain tumour cell line, like human glioma cell lines, shows a large capacity for PLDR. Cisplatin administered at 6 micrograms/ml for 1 hour immediately following acute irradiation (18 Gy) is shown to cause significant inhibition of PLDR, while 3 micrograms/ml causes little inhibition.

Major histocompatibility complex class IV restriction fragment length polymorphism markers in replicated meat-type chicken lines divergently selected for high or low early immune response.

Information on MHC may improve the efficiency of selection for immunological traits via the application of marker assisted selection or by selecting directly for a specific restriction fragment length polymorphism (RFLP) band or MHC haplotype. An experimental procedure is presented here for identifying MHC genes that are related to early immune response. A Class IV cDNA clone was used to probe Southern blots of erythrocyte genomic DNA from chickens.

Is ovarian cancer associated with an increased frequency of germinal inclusion cysts?

It has been proposed that epithelial ovarian cancers arise in germinal inclusion cysts of the ovary, which are thought to form as stigmata of ovulation. To evaluate whether the frequency of germinal inclusion cysts is associated with ovarian cancer, the authors counted the germinal inclusion cysts in single slides of sections from ovaries of 148 women who underwent incidental oophorectomy and from the contralateral ovaries of 37 women with unilateral ovarian cancer at Columbia-Presbyterian Medical Center, New York, New York, in 1985-1991. The mean number of germinal inclusion cysts was 2.

Time preference in medical decision making and cost-effectiveness analysis.

Cost-effectiveness analyses usually quantify peoples' attitudes towards delayed outcomes using the exponential discount model. The authors examined three assumptions of this model by assessing the time preferences of individuals towards hypothetical health states and calculating implicit annual discount rates. Of a random sample of medical students, house officers, and attending physicians, 121 participated, reflecting a response rate of 81%.

Genetic and environmental influences on serum lipid levels in twins.

Background: The extent to which serum lipid levels are affected by genetic and environmental factors remains a point of controversy. We examined both genetic and environmental influences on serum lipid levels in twins reared either together or apart who participated in the Swedish Adoption/Twin Study of Aging.

Methods: We studied 302 pairs of twins (mean age, 65.

Particle beam liquid chromatography/mass spectrometry with negative ion chemical ionization for the confirmation of ivermectin residue in bovine milk and liver.

Particle beam liquid chromatography/mass spectrometry (LC/MS) using negative ion chemical ionization was applied to the analysis of ivermectin residue in bovine milk and liver. Samples were prepared by liquid/liquid extraction followed by alumina B solid-phase extraction clean-up. On-line LC/MS of extracts was carried out on a C-18 bonded silica column.

The febrile parenteral drug user: a prospective study in 121 patients.

Objective: To determine the most efficient approach to the diagnosis of infective endocarditis (IE) in febrile parenteral drug users (PDUs) and evaluate possible effects of human immunodeficiency virus (HIV) infections or acquired immunodeficiency syndrome (AIDS) on susceptibility to IE and final outcome.

Design: A prospective study of appropriate patients admitted on 149 random sampling days during a 14-month period and review of past experience with IE, HIV, and AIDS admissions to hospital.

Setting: An urban university hospital.