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排序方式: 共有2476条查询结果,搜索用时 30 毫秒
41.
M A ElSohly D F Stanford T P Murphy B M Lester L L Wright V L Smeriglio J Verter C R Bauer S Shankaran H S Bada H C Walls 《Journal of analytical toxicology》1999,23(6):436-445
The analysis of meconium specimens for metabolites of substances of abuse is a relatively accurate method for the detection of fetal exposure to drugs. Most of the methods reported in the literature before the early 1990s relied on radioimmunoassays. The purpose of this study was to develop and validate methods for meconium sample preparation for the screening and gas chromatography-mass spectrometry (GC-MS) confirmation of meconium extracts for cannabinoids, cocaine, opiates, amphetamines, and phencyclidine. EMIT and TDx immunoassays were evaluated as screening methods. The sample preparation method developed for screening included extraction and purification prior to analysis. Cutoff levels were administratively set at 20 ng/g for 11-nor-delta9-THC-9-COOH (THCCOOH) and phencyclidine and at 200 ng/g for benzoylecgonine, morphine, and amphetamines, although lower levels could be detected in meconium using the EMIT-ETS system. Ninety-five meconium specimens were subjected to the screening procedure with GC-MS confirmation of presumptive positives. In addition, 30 (40 for cocaine) meconium specimens were subjected to GC-MS analysis for all analytes regardless of the screening results to determine the false-negative rate, if any, of the immunoassay. Although there were no false negatives detected, the GC-MS confirmation rate for the immunoassay-positive specimens was generally low, ranging from 0% for amphetamines to 75% for opiates. The lowest rate of confirmed positives was found with the cannabinoids, suggesting that tetrahydrocannabinol (THC) metabolites other than free 11-nor-9-carboxy-delta9-THC may be major contributors to the immunoassay response in meconium. 相似文献
42.
The commentators suggest that our approach may be too limited to account for many of the factors which influence stress-related behaviour, yet too general to help us interpret the neurochemical coding of behavioural responses to stress. In our reply we argue that the strategy described in our Critique both confronts the issues discussed in the Commentaries and is more objective and rigorous than approaches used currently. 相似文献
43.
J L Stanford 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1991,99(2):103-113
BCG is the only vaccine for tuberculosis and leprosy known to be effective in at least some places. Unfortunately it tends to be less successful in just those areas of the developing world where a vaccine is most needed. Although molecular biology offers the prospect of alternatives, these still lie in the indefinite future, and the best use has to be made of BCG. A number of preparations are available from different manufacturers, and a vaccine should be selected with good evidence of efficacy, and a low incidence of complications. Selection of the optimal age for administering BCG should be based on factors pertaining in the area where it is to be used. The influence of contact with environmental mycobacteria, the age at which mycobacterial diseases occur, and the logistics of vaccine delivery must be taken into account. The addition of a suspension of killed Mycobacterium vaccae to BCG may increase its efficacy. Skin test data show that recognition of antigens common to all mycobacterial species and thought to be the first step in the protective immune response, is significantly enhanced by the additive. M. vaccae also contains a substance, or substances, "switching off" the tissue destructive aspect of the Koch phenomenon that is part of the immunopathology of tuberculosis. A suspension of killed M. vaccae alone can be used to enhance immune responses of persons unsuitable for BCG vaccination, such as those already tuberculin positive, and those with scars of earlier BCG vaccination. 相似文献
44.
Proton magnetic resonance spectroscopy improves outcome prediction in perinatal CNS insults. 总被引:4,自引:0,他引:4
Munaf Kadri Stanford Shu Barbara Holshouser Douglas Deming Andrew Hopper Ricardo Peverini Stephen Ashwal 《Journal of perinatology》2003,23(3):181-185
OBJECTIVE: Prediction of neurologic outcome is difficult in neonates with acute nervous system injury. Previous studies using proton magnetic resonance spectroscopy ((1)H-MRS) have been used to predict short-term neurologic outcome in neonates with a variety of neurologic insults. We were interested in determining the effectiveness of combining clinical evaluation and spectroscopy obtained at the time of injury in predicting neurologic outcome at 24 months. STUDY DESIGN: We studied 33 neonates with acute central nervous system injury, 5.8+/-3.7 days of injury, owing to hypoxic-ischemic encephalopathy. Neonates were assessed using clinical variables (initial arterial pH, initial blood glucose, Sarnat score, electroencephalography) and spectroscopy (NAA/Cho, NAA/Cre, Cho/Cre, and lactate). Neonates were divided into two outcome groups: good/moderate and poor. Differences between the groups were assessed using chi(2) and t-test analyses. We analyzed the best predictors of outcome using discriminant analysis and calculated sensitivity, specificity, positive, and negative predictive values for each variable independently and in combination. RESULTS: There were significant differences between the good/moderate and poor outcome for the Sarnat score, EEG, lactate, and NAA/Cho. Spectroscopy combined with clinical variables improved sensitivity, but not specificity for predicting outcome. The presence of lactate had the best individual predictive value. Combination of the clinical with the MRS variables had the highest predictive value. CONCLUSION: Proton magnetic resonance spectroscopy done early after injury improves the ability to predict neurologic outcome at 24 months of age. 相似文献
45.
Marilie D Gammon Mary Beth Terry Nadir Arber Wong-Ho Chow Harvey A Risch Thomas L Vaughan Janet B Schoenberg Susan T Mayne Janet L Stanford Robert Dubrow Heidrun Rotterdam A Brian West Joseph F Fraumeni I Bernard Weinstein Hanina Hibshoosh 《Cancer epidemiology, biomarkers & prevention》2004,13(1):34-39
This study was undertaken to determine whether selected risk factors for esophageal and gastric cancer are associated with tumors that overexpress cyclin D1. Archived tumor tissue was available for 630 esophageal and gastric cancer patients who participated in a population-based case-control study. Patients were categorized into case groups based on whether protein overexpression of the cyclin D1 gene, as assessed by immunohistochemistry, was present (cyclin D1+, n = 285) or not (cyclin D1-, n = 345) in the tumor. The distribution of risk factors in each of these case groups was then compared with the distribution among the 695 controls. Multivariate-adjusted odds ratios (OR) for esophageal adenocarcinoma were reduced in relation to use of aspirin and other nonsteroidal anti-inflammatory drug (NSAID) use but only among patients with cyclin D1+ tumors (0.45, 95% confidence interval [CI] = 0.26, 0.79) and not among those with cyclin D1- tumors (1.12, 95% CI = 0.67, 1.86). A similar pattern was observed for gastric cardia adenocarcinomas. In contrast, ORs for esophageal squamous cell carcinoma and noncardia gastric adenocarcinomas in relation to NSAID use were reduced, regardless of cyclin D1 status. ORs did not vary with cyclin D1 status in relation to alcohol, body size, or cigarette smoking, with the following exception; for noncardia gastric adenocarcinomas the cyclin D1- tumors showed a 2-fold elevation in the OR with ever smoking. These data suggest that the reduction in risk associated with NSAID use may be restricted to those esophageal and gastric cardia adenocarcinomas that overexpress cyclin D1. 相似文献
46.
Serologic evidence of human papillomavirus 16 and 18 infections and risk of prostate cancer. 总被引:2,自引:0,他引:2
Karin A Rosenblatt Joseph J Carter Lori M Iwasaki Denise A Galloway Janet L Stanford 《Cancer epidemiology, biomarkers & prevention》2003,12(8):763-768
Human papillomavirus (HPV) subtypes 16 and 18 are sexually transmitted and have been associated with an increased incidence of several anogenital tumors. Although previous epidemiological studies have suggested that sexual behaviors such as an early age at first intercourse and larger numbers of sexual partners are also related to an increased risk of prostate cancer, seroepidemiological studies of these infectious agents in relation to prostate cancer have produced differing results. To further evaluate this potential relationship, we completed a population-based control study in King County, Washington. Middle-aged (40-64 years) men diagnosed with prostate cancer (n = 642) were ascertained through the Seattle-Puget Sound Surveillance, Epidemiology, and End Results cancer registry between January 1993 and December 1996. Controls (n = 570) of similar age were selected from the same population as the cases by random digit dialing. Overall, there was no association between serological evidence of prior HPV-16 (adjusted odds ratio, 1.06; 95% confidence interval, 0.71-1.57) or HPV-18 (adjusted odds ratio, 1.36; 95% confidence interval, 0.69-2.69) infection and the risk of prostate cancer. Analyses of clinical features demonstrated no relationship between HPV infection status and Gleason score, stage of disease, or a combined measure of disease aggressiveness. Our findings indicate that HPV-16 and HPV-18 are not associated with prostate cancer risk. 相似文献
47.
Association of HPC2/ELAC2 polymorphisms with risk of prostate cancer in a population-based study. 总被引:1,自引:0,他引:1
Janet L Stanford Leah P Sabacan Elizabeth A Noonan Lori Iwasaki Jianfen Shu Ziding Feng Elaine A Ostrander 《Cancer epidemiology, biomarkers & prevention》2003,12(9):876-881
Genetic polymorphism in HPC2/ELAC2 was recently associated with risk of sporadic prostate cancer. To determine the contribution of two HPC2/ELAC2 missense variants (Ser217Leu and Ala541Thr) to the risk of developing prostate cancer, we conducted a population-based case-control study of middle-aged men (40-64 years). Cases (n=591) were ascertained from the Seattle-Puget Sound Surveillance, Epidemiology, and End Results Cancer Registry and Controls (n=538) from the same general population were identified through random-digit dialing. Subjects were residents of King County, Washington, and were frequency matched on age. Cases (32%) had a slightly higher frequency of the Leu217 variant compared with controls (29%), but there were no differences in the frequency of the Thr541 allele (4%). When considering joint genotypes, white men homozygous for the Leu217 variant on an Ala541/Ala541 background had an increased risk of prostate cancer [odds ratio (OR)=1.84; 95% confidence interval (CI), 1.11-3.06]. Different risk profiles were also observed when cases were stratified by disease aggressiveness. Men with at least one Leu217 allele had an elevated risk (OR=1.34; 95% CI, 1.02-1.76) of less aggressive prostate cancer (localized stage and Gleason score < or = 7), with a stronger association among men with two Leu217 alleles (OR=1.73; 95% CI, 1.08-2.77). The Ala541Thr polymorphism was not associated with risk, and neither variant was associated with more aggressive prostate cancer phenotypes. We estimate that the Ser217Leu genotype may account for approximately 14% of less aggressive prostate cancer cases and 9% of all sporadic cases in the general United States population of white men 相似文献
48.
Ionizing radiation is a carcinogen that induces oxidative DNA damage. 8-
Hydroxy-2'-deoxyguanosine (8-OHdG) is a relatively abundant, mutagenic
lesion that is widely regarded as a reliable index of oxidative DNA damage.
The purpose of this study was to examine the effects of X- radiation on
levels of 8-OHdG in the context of an experimental model for breast cancer
in which chronic radiation exposure has been shown to be carcinogenic in
Sprague-Dawley rats. A secondary objective of this study was to determine
if the use of phenol during DNA isolation affected the concentration of
8-OHdG subsequently measured. Our results indicate that a profoundly
carcinogenic dose of radiation induced a small but significant increase in
8-OHdG concentration in mammary gland DNA, and that the use of a
phenol-based versus a salt-based method of DNA isolation had no significant
impact on the levels of 8-OHdG detected in either control or irradiated
tissue.
相似文献
49.
Dackiw AP Sussman JJ Fritsche HA Delpassand ES Stanford P Hoff A Gagel RF Evans DB Lee JE 《Archives of surgery (Chicago, Ill. : 1960)》2000,135(5):550-5; discussion 555-7
50.
Royden Stanford Danae Lowell Rajeeva Raju Shylaja Arya 《The Journal of foot and ankle surgery》2012,51(4):475-478
We report on a 79-year-old man with a chronic venous stasis ulceration of >20 years' duration in the left medial leg presenting to our clinic after admission for bleeding and suspected infection of his ulceration. This lesion had been biopsied in 1999 and was found to be a benign, chronic venous insufficiency ulceration. Plain film radiographs as well as a bone scan did not identify osteomyelitis. Because of the hypertrophic, nodular appearance of this ulceration, it was the clinicians' discretion to perform a repeat biopsy of the lesion. Biopsy revealed invasive, well-differentiated squamous cell carcinoma. A computed tomography scan subsequently identified a suspicious inguinal lymph node, and an ultrasound-guided needle aspiration revealed metastatic squamous cell carcinoma of the biopsied lymph node. Above-knee amputation was indicated at this time and was performed in conjunction with local superficial inguinal lymph node resection, after which the patient was discharged from our service. 相似文献