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排序方式: 共有1738条查询结果,搜索用时 15 毫秒
981.
982.
A pilot study was conducted to investigate the hypothesis that dietary tryptophan manipulation would influence self-report affective status in alcoholic males. No significant effect of dietary manipulation was observed on the tryptophan/large neutral amino acids ratio or psychological indices of affect. The notion that dietary manipulation may be utilized in improving mood state in alcoholic males was not supported. 相似文献
983.
Magnetic resonance (MR) imaging was compared with computed tomography (CT) in 13 children with mediastinal abnormalities. CT and MR provided comparable information regarding the presence and size of the mediastinal lesions. The MR imaging technique that was most reliable in detecting a mass was a T1-weighted spin-echo pulse sequence. MR better discriminated mediastinal masses and enlarged nodes from vascular structures and was more sensitive than CT in detecting intraspinal extension. However, CT demonstrated calcification and bronchial abnormalities not seen on MR images. It is concluded that MR may be more helpful than CT in evaluating posterior mediastinal tumors, since there is a likelihood of intraspinal extension. In other cases, however, CT continues to be the procedure of choice to supplement plain radiography in children with suspected mediastinal neoplasms. 相似文献
984.
985.
J B Bass E L Hawkins J R Bonner H M Pollock 《Diagnostic microbiology and infectious disease》1983,1(2):95-106
We prospectively compared the usefulness of a bronchoscopic protected catheter technique with the results from sputum cultures in the evaluation of moxalactam, a new beta-lactam antibiotic. The significance of a given isolate on protected catheter culture was determined by quantitative bacteriology. 32 patients with community-acquired pneumonia were enrolled in the study and 31 grew common lower respiratory tract pathogens from their protected catheter specimen. The most common single pathogens recovered were Streptococcus pneumoniae (11 patients) and Haemophilus influenzae (2). Mixed flora, predominantly anaerobes, were isolated from 15 patients, and 3 patients had mixed aerobic infections. All seven bacteremic cases had the identical organism isolated from the protected catheter specimen, confirming the accuracy of the technique. Comparisons with sputum cultures showed that the predominant organism on sputum culture was the same as that obtained from the protected catheter culture in only 13% of the cases. Sputum cultures revealed either no pathogen or a different pathogen in 23 cases, and no sputum could be obtained in 4. Compared to cultures of expectorated sputum, we found the protected catheter bronchoscopic culture technique to have the following advantages in the bacteriologic evaluation of moxalactam: 1) greater accuracy and sensitivity in bacteremic patients; 2) accurate delineation of the bacteriology of infections; and 3) a higher percentage of patients with evaluable bacteriology leading to greater efficiency during the investigation. 相似文献
986.
Yuriy M. Sivolap James Bonner 《Proceedings of the National Academy of Sciences of the United States of America》1971,68(2):387-389
Chromosomal RNA, which is a component of the chromosomes of higher organisms, and whose participation is required for sequence-specific interaction of chromosomal proteins with chromosomal DNA, occurs in chromosomes bound to DNA. We have found that the DNA sequences to which chromosomal RNA binds are repetitive ones. 相似文献
987.
Non-Hodgkin lymphoma: computed tomographic demonstration of unusual extranodal involvement 总被引:2,自引:0,他引:2
With the advent of computed tomography, lymphomatous involvement of sites other than lymph nodes is being seen with increasing frequency. Review of computed tomographic scans in 400 patients with newly diagnosed or recurrent non-Hodgkin lymphoma revealed 37 patients to have involvement of 56 unusual sites below the diaphragm: psoas/iliacus muscle (16 patients), kidney (13 patients), pancreas (5 patients), adrenal (4 patients), skin/subcutaneous tissue (4 patients), abdominal wall musculature (4 patients), peritoneum (4 patients), omentum (3 patients), and female reproductive tract (3 patients). These were mostly seen in patients with lymphomas of diffuse architecture, especially diffuse histiocytic lymphoma. Concomitant retroperitoneal and/or mesenteric adenopathy was very common; extranodal involvement was rarely the only site of initial or recurrent lymphoma. 相似文献
988.
Thompson RL Lewis SL Murphy MR Hale JM Blackwell PH Acton GJ Clough DH Patrick GJ Bonner PN 《Biological research for nursing》2004,5(4):319-330
The purpose of this study was to compare emotional and biological responses of men and women who are spousal caregivers of patients with Alzheimer's disease (AD). Quality-of-life measurements, bioinstrumentation data, and immunophenotype assessments were obtained from female and male spousal caregivers of patients with AD. Spousal caregivers (women, n = 45 with average age 69.7; men, n = 16 with average age 71.4 years) completed questionnaires that assessed psychosocial variables. Blood was drawn and lymphocyte subsets (including natural killer [NK] cell number) were determined using flow cytometry. The degree of relaxation was determined measuring muscle tension (EMG) in the frontalis and trapezius muscles, skin conductance, skin temperature, and heart rate. Male spousal caregivers, as compared to female spousal caregivers, had significantly lower levels of stress, depression, caregiver burden (subjective), anxiety, anger-hostility, and somatic symptoms and higher levels of mental health, sense of coherence, NK cell number, and social and physical functioning. There were no statistically significant differences between the 2 groups in social support, coping resources, or T, T suppressor, or activated T cells. Women had more T helper cells and fewer NK cells than men. Men had fewer manifestations of a physiological stress response, as indicated by bioinstrumentation parameters. Unique sex-specific issues need to be considered when strategies are implemented to assist the increasing number of caregivers as our society ages. 相似文献
989.
Flesch G Tudor D Denouel J Bonner J Camisasca R 《International journal of clinical pharmacology and therapeutics》2003,41(7):299-308
Oxcarbazepine (trileptal) oral suspension has been reformulated and a study was performed to compare the bioavailability after single doses and at steady state of the current and former oral suspension versus the marketed film-coated tablets and to compare the bioavailability of the current and former oral suspension. The results support the switch from the former oral suspension to the current oral suspension and also from both oral suspensions to the film-coated tablet and vice versa. The study was an open-label, single-center, 3-way crossover trial. Each treatment period consisted of a single dose of 600 mg oxcarbazepine on Day 1, 600 mg oxcarbazepine b.i.d. repeated administration from Day 4 up to including Day 7, and a final dose of 600 mg oxcarbazepine administered on the morning of Day 8. Blood samples were taken on Day 1, Day 7 and Day 8 (pre-dose). Plasma concentrations of the main metabolite of oxcarbazepine (MHD) were determined using a validated HPLC assay. The 2 oral suspensions were compared with the film-coated tablet as reference formulation under fasted conditions. Also the current oral suspension was compared with the former oral suspension. These comparisons were made using data following single dose administration and under steady state conditions. Plasma AUC for single dose and AUC(0-12h) at steady state and plasma Cmax, log-transformed (natural base) were used for the assessment of bioequivalence. The 90% confidence interval (CI) approach was used for testing bioequivalence. Bioequivalence was accepted if CI was contained within the region (0.8, 1.25). At steady state, both the former and the current oral suspensions showed bioequivalence with the film-coated tablet with respect to AUC and Cmax. The current oral suspension was also bioequivalent when compared to the former oral suspension with respect to AUC and Cmax. After single dose, the former oral suspension was bioequivalent when compared to the film-coated tablet with respect to both AUC and Cmax. However, the current oral suspension was bioequivalent to both the film-coated tablet and the former oral suspension with respect to AUC but not to Cmax. 相似文献
990.
Mueller DC Bonner JS McDonald SJ Autenrieth RL Donnelly KC Lee K Doe K Anderson J 《Environmental toxicology and chemistry / SETAC》2003,22(9):1945-1955
Six toxicity assays were compared to determine their efficacy in assessing toxicity dynamics during a wetland bioremediation study. The toxicity bioassays used were the Microtox 100% elutriate test, Microtox Solid Phase Test (SPT), amphipod assay, P450 reporter gene system, Toxi-ChromoPad test and a Salmonella/microsome assay. Oiled sediments were analyzed for toxicity in the petroleum biostimulation experiment conducted along the San Jacinto River, near Houston (TX, USA). The bioassays were evaluated for their ability to measure acute toxicity, chronic toxicity, and the mutagenic potential of amended oiled plots as compared to oiled and unoiled control plots. Amendments were diammonium phosphate alone or in combination with potassium nitrate, which served as an alternate electron acceptor. With exception of the Toxi-ChromoPad and Salmonella tests, the bioassays exhibited a significant increase in toxicity after oil application. Microtox bioassays detected significant sediment toxicity up to 29 d after oil and amendment application. The Microtox solid phase test results correlated strongly with gas chromatography-mass spectrometry analyses of total target saturate and aromatic hydrocarbons. The amphipod assay detected initial toxicity with a decline to day 70, followed by a significant increase in toxicity on day 140 in plots receiving nutrient amendments, which may be in response to excessive nutrient application. Low levels of enzyme induction were observed with the P450 reporter gene system assay in all oiled sediments throughout the study, suggesting low but persistent levels of polycyclic aromatic hydrocarbons. Of the six tests, the two Microtox tests and the amphipod test showed the most potential in evaluating petroleum toxicity in wetland sediments. 相似文献