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51.
MK Barry JA van Heerden DR Farley CS Grant GB Thompson DM Ilstrup 《Canadian Metallurgical Quarterly》1998,22(6):599-603; discussion 603-4
We currently recommend excision of adrenal incidentalomas > or = 4 cm in size and all hormonally active tumors. The optimal management and follow-up of smaller nonfunctioning tumors are controversial. The aim of this study was to determine the clinical outcome of a well defined population of patients with incidentalomas followed without operative intervention. The study group comprised 231 patients, identified from the records of abdominal or thoracic computed tomographic (CT) scans performed between 1985 and 1989. The primary outcome variable analyzed was survival. Follow-up was obtained by office records, telephone contact, or letter. There were 101 male and 130 female patients with a mean age at diagnosis of 64 years (range 5-86 years). Most adrenal tumors were unilateral (right 113; left 98); 20 were bilateral. Mean tumor size was 2 cm (range 1-6 cm). In nine (4%) patients the tumor was > or = 4 cm. Follow-up [mean 7 years; range 1 month (patient died) to 11.7 years] was complete in 224 (97%) patients. Ninety-one (39%) patients had one or more additional CT scans performed during the follow-up period, with only four patients demonstrating a > 1 cm increase in the size of the adrenal mass. Surgical excision of these four lesions identified benign pathology. Eighty-one (35%) patients died of conditions unrelated to adrenal pathology. No patient developed subsequent adrenal hyperfunction or adrenal malignancy. Within the context of our guidelines, conservative management of adrenal incidentalomas considered benign or nonfunctioning at diagnosis is appropriate. Additional information provided by repeat CT scanning appears to confer limited benefit. This study does not support laparoscopic removal of small, nonfunctional adrenal tumors, as has been suggested. 相似文献
52.
MK Potts 《Canadian Metallurgical Quarterly》1997,42(4):348-362
Using socioemotional selectivity theory as a framework, the study described in this article examined the extent to which social support from friends both within and outside of a retirement community was associated with depression. Although levels of social support from friends within the retirement community were quantitatively high, they failed to have a significant effect on depression. In contrast, social support from friends living elsewhere consistently predicted low levels of depression. Practice implications include the importance of maintaining friendship ties with people living elsewhere and of strengthening friendship ties within the retirement community. 相似文献
53.
P. Neal A. D. Campbell D. Firestone M. H. Aldridge 《Journal of the American Oil Chemists' Society》1969,46(10):561-562
Dimethylpolysiloxanes, which are difficult to determine in fatty foods, can be separated at low temperatures by special freeze-out
apparatus. Final determination is made by atomic absorption, visible or ultraviolet spectrometry. Recoveries from cottonseed
oil and cake mix ranged from 95% to 110%. 相似文献
54.
Wan J Tokunaga TK Kim Y Brodie E Daly R Hazen TC Firestone MK 《Environmental science & technology》2008,42(20):7573-7579
Bioreduction-based strategies for remediating uranium (U)-contaminated sediments face the challenge of maintaining the reduced status of U for long times. Because groundwater influxes continuously bring in oxidizing terminal electron acceptors (O2, NO3(-)), it is necessary to continue supplying organic carbon (OC) to maintain the reducing environment after U bioreduction is achieved. We tested the influence of OC supply rates on mobility of previously microbial reduced uranium U(IV) in contaminated sediments. We found that high degrees of U mobilization occurred when OC supply rates were high, and when the sediment still contained abundant Fe(III). Although 900 days with low levels of OC supply minimized U mobilization, the sediment redox potential increased with time as did extractable U(VI) fractions. Molecular analyses of total microbial activity demonstrated a positive correlation with OC supply and analyses of Geobacteraceae activity (RT-qPCR of 16S rRNA) indicated continued activity even when the effluent Fe(II) became undetectable. These data support our hypothesis on the mechanisms responsible for remobilization of U under reducing conditions; that microbial respiration caused increased (bi)carbonate concentration and formation of stable uranyl carbonate complexes, thereby shifted U(IV)/U(VI) equilibrium to more reducing potentials. The data also suggested that low OC concentrations could not sustain the reducing condition of the sediment for much longer time. Bioreduced U(IV) is not sustainable in an oxidizing environment for a very long time. 相似文献
55.
OBJECTIVE: To determine whether administration of commercially available Escherichia coli antiserum to neonatal foals would affect serum IgG concentration or morbidity and mortality rates during the first 60 days of life. DESIGN: Randomized controlled trial. ANIMALS: 271 neonatal foals on 4 well-managed farms. PROCEDURE: Foals were randomly assigned to a treatment or control group. All foals were allowed to suckle colostrum normally. In addition, treatment-group foals were given E coli antiserum (10 micromilligrams) orally between 0 and 8 hours after birth. Serum samples were obtained between 18 and 36 hours after birth, and serum IgG concentration was determined. Foals were monitored for the first 60 days after birth, and causes of disease or death were recorded. RESULTS: Groups did not differ significantly in regard to breed, sex, month of birth, season of birth, age of dams, parity of dams, duration of gestation, or specific gravity of colostrum before suckling. In addition, groups did not differ significantly in regard to mean serum IgG concentration, prevalence of complete or partial failure of passive transfer of immunity, frequency or causes of disease, or frequency of death from infectious causes. CLINICAL IMPLICATIONS: In this group of foals on well-managed farms, administration of E coli antiserum did not alter serum IgG concentrations or morbidity and mortality rates during the first 60 days of life. 相似文献
56.
KL Syrjala SL Roth-Roemer JR Abrams JM Scanlan MK Chapko S Visser JE Sanders 《Canadian Metallurgical Quarterly》1998,16(9):3148-3157
PURPOSE: To describe the prevalence of sexual difficulties in men and women after marrow transplantation (MT), and to define medical, demographic, sexual, and psychologic predictors of sexual dysfunction 3 years after MT. PATIENTS AND METHODS: Four hundred seven adult MT patients were assessed pretransplantation. Survivors repeated measures of psychologic and sexual functioning at 1 and 3 years posttransplantation. RESULTS: Data were analyzed from 102 event-free 3-year survivors who defined themselves as sexually active. Men and women did not differ in sexual satisfaction pretransplantation. At 1 and 3 years posttransplantation, women reported significantly more sexual dysfunction than men. Eighty percent of women and 29% of men reported at least one sexual problem by 3 years after MT. No pretransplantation variables were significant predictors of 3-year sexual satisfaction for women. For men, pretransplantation variables of older age, poorer psychologic function, not being married, and lower sexual satisfaction predicted sexual dissatisfaction at 3 years (R2=.28; P < .001). Women who were more dissatisfied 3 years after MT did not receive hormone replacement therapy (HRT) at 1 -year posttransplantation and were less satisfied at 1 year, but not pretransplantation (R2=.35; P < .001). CONCLUSION: Sexual problems are significant in the lives of MT survivors, particularly for women. Although HRT before 1 year posttransplantation improves sexual function, it does not ensure sexual quality of life. Intervention for women is needed to apply hormonal, mechanical, and behavioral methods to prevent sexual difficulties as early after transplantation as possible. 相似文献
57.
This study investigated the nature of selective attention deficits after severe closed head injury (CHI). Twenty participants with severe CHI (greater than 1 year postinjury) and 20 matched controls completed search and nonsearch visual selective attention tasks under conditions of low (Experiment 1) and high (Experiment 2) target-distractor similarity. In the search situations, participants searched visual displays that contained 1, 4, or 8 items for the targets. In the nonsearch situations, the location of the targets was visually cued with a peripheral arrow. The results revealed that in both the low and high target-distractor similarity search conditions. CHI participants required a longer time than controls to locate and identify the target. In contrast, in the nonsearch condition, CHI participants were able to successfully ignore irrelevant task information when target-distractor similarity was low. However, when target-distractor similarity was high, CHI participants had more difficulty than controls ignoring the irrelevant information. These results suggest that, in comparison to controls, CHI participants may be at a disadvantage in selective attention situations when visual search is required and when the discriminability between targets and distractors is difficult. 相似文献
58.
MK Storch S Piddlesden M Haltia M Iivanainen P Morgan H Lassmann 《Canadian Metallurgical Quarterly》1998,43(4):465-471
Blue light responses in higher plants can be mediated not only by specific blue light receptors, but also by the red/far-red photoreversible phytochrome system. The question of interdependence between these photoreceptors has been debated over many years. The availability of Arabidopsis mutants for the blue light receptor CRY1 and for the two major phytochromes phyA and phyB allows a reinvestigation of this question. The analysis of photocontrol of seed germination, inhibition of hypocotyl growth and anthocyanin accumulation clearly demonstrates that (i) phyA shows a strong control in blue light responses especially at low fluence rates; (ii) phyB mediated induction reactions can be reversed by subsequent blue light irradiations; and (iii) CRY1 mediates blue light controlled inhibition of hypocotyl growth only at fluence rates higher than 5 mumol m-2s-1 and independently of phytochrome A and B. 相似文献
59.
GB Karlsson M Halloran D Schenten J Lee P Racz K Tenner-Racz J Manola R Gelman B Etemad-Moghadam E Desjardins R Wyatt NP Gerard L Marcon D Margolin J Fanton MK Axthelm NL Letvin J Sodroski 《Canadian Metallurgical Quarterly》1998,188(6):1159-1171
CD4+ T lymphocyte depletion in human immunodeficiency virus type 1 (HIV-1)-infected humans underlies the development of acquired immune deficiency syndrome. Using a model in which rhesus macaques were infected with chimeric simian-human immunodeficiency viruses (SHIVs), we show that both the level of viremia and the structure of the HIV-1 envelope glycoprotein ectodomains individually contributed to the efficiency with which CD4(+) T lymphocytes were depleted. The envelope glycoproteins of recombinant SHIVs that efficiently caused loss of CD4(+) T lymphocytes exhibited increased chemokine receptor binding and membrane-fusing capacity compared with those of less pathogenic viruses. These studies identify the HIV-1 envelope glycoprotein ectodomains as determinants of CD4(+) T lymphocyte loss in vivo and provide a foundation for studying pathogenic mechanisms. 相似文献
60.