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排序方式: 共有4114条查询结果,搜索用时 15 毫秒
31.
Elevated plasma interleukin-6 and increased severity and mortality in alcoholic hepatitis. 总被引:6,自引:2,他引:6
N Sheron G Bird J Goka G Alexander R Williams 《Clinical and experimental immunology》1991,84(3):449-453
Recent studies in alcoholic hepatitis have proposed a role for the cytokine tumour necrosis factor-alpha (TNF-alpha) a mediator of endotoxic shock in sepsis. In this study plasma levels of the closely related cytokine interleukin-6 (IL-6) were assayed in 96 samples from 58 patients with severe alcoholic hepatitis, and 69 patients in control groups (21 normal, 10 alcoholic without liver disease, 10 inactive alcoholic cirrhosis, 18 chronic liver disease, 10 chronic renal failure). Plasma IL-6 levels were markedly elevated in patients with alcoholic hepatitis when compared with all control groups (P less than 0.001). IL-6 levels were higher in patients who died (P = 0.04) and correlated with the features of severe disease including: increased grade of encephalopathy, increased neutrophil count, increased prothrombin ratio, hypotension, increased serum creatinine and increased serum bilirubin. Surprisingly, no correlation was found between levels of plasma IL-6 and plasma TNF-alpha or endotoxin, or the presence of infection; an inverse correlation was found between plasma IL-6 and serum globulins. These findings provide further evidence that the IL-6/TNF cytokine system is activated in severe alcoholic hepatitis and may mediate hepatic or extra-hepatic tissue damage. 相似文献
32.
Somatic Mutation in Human B-Cell Tumors 总被引:15,自引:0,他引:15
Ronald Levy Shoshana Levy Michael L. Cleary William Carroll Shinichiro Kon Jeffrey Bird Jeffrey Sklar 《Immunological reviews》1987,96(1):43-58
33.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2002,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's
gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing
radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers,
and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed
with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant,
and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender
were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women
was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative
English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and
while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology
practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient
way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed
and sensitive manner. 相似文献
34.
J D Hemming P Quirke C Womack M Wells C W Elston C C Bird 《Journal of clinical pathology》1987,40(6):615-620
Histopathological assessment and flow cytometric analyses were carried out on 32 placentas (representative of each trimester) and 88 molar pregnancies. Three first trimester placentas were triploid, and the remaining 29 placentas were diploid. Of the 88 cases originally diagnosed as molar pregnancies, 26 were triploid (two complete moles, 20 partial moles, and four hydropic abortions); 59 were diploid (46 complete moles, 10 partial moles, three hydropic abortions); one was tetraploid (partial mole); and two were DNA aneuploid (one partial mole, one complete mole). A significantly increased hyperdiploid fraction (a measure of cell proliferation) was detected in diploid complete moles (p less than 0.0001) and cases of persistent trophoblastic disease (p less than 0.001) when compared with diploid placentas and diploid partial moles. All seven cases of established persistent trophoblastic disease, for which follow up was available, were diploid and showed high hyperdiploid fractions within the range for diploid complete moles. These findings suggest that flow cytometric DNA measurements may be an important aid in the diagnosis of molar pregnancy. The high degree of cell proliferation found in this study may explain the premalignant potential of complete hydatidiform moles. 相似文献
35.
36.
Repeated injections of a ciliary neurotrophic factor analogue leading to long-term photoreceptor survival in hereditary retinal degeneration 总被引:6,自引:0,他引:6
Chong NH Alexander RA Waters L Barnett KC Bird AC Luthert PJ 《Investigative ophthalmology & visual science》1999,40(6):1298-1305
PURPOSE: To determine whether ciliary neurotrophic factor (CNTF) or brain-derived neurotrophic factor (BDNF) treatment leads to long-term photoreceptor survival in hereditary retinal degeneration. METHODS: An autosomal dominant feline model of rod-cone dystrophy was used throughout the study with two normal animals. In the first experiment, intravitreal injections of a human CNTF analogue (Axokine; Regeneron Pharmaceuticals, Tarrytown, NY) were administered to one eye of each animal (n = 10) beginning on postnatal day 10 and were repeated every 4 weeks. Clinical and histopathologic examinations were performed at 5.5, 9.5, and 13.5 weeks. In the second experiment, animals (n = 17) were randomly assigned to receive intravitreal injections of either Axokine (at half the initial dose), human BDNF, or the vehicle for Axokine to one eye at 5.5 weeks. The same therapy was repeated every 4 weeks in each group. Clinical and histopathologic examinations were performed at 9.5, 13.5, and 17.5 weeks. Photoreceptor survival was assessed by cell counting. Apoptotic cells were identified by morphology and a modified TdT-dUTP terminal nick-end labeling (TUNEL) technique. In the third experiment, two normal animals were treated with Axokine as in the first experiment. Glial fibrillary acidic protein ((GFAP) immunohistochemistry was performed to assess glial cell reaction. RESULTS: In the first two experiments, Axokine significantly prolonged photoreceptor survival (P < 0.01) and reduced the presence of apoptotic cells (P < 0.05) and TUNEL-positive cells (P < 0.05). In the second experiment, results in the the BDNF- and sham-injected eyes were not significantly different from those in the untreated eyes. Minimal posterior subcapsular cataract and mild retinal folds were found in all Axokine-treated eyes in both dystrophic and normal animals. These complications were milder in the second experiment when injections were started later and at a reduced dose. GFAP immunolabeling was also increased in all Axokine-treated eyes. CONCLUSIONS: Axokine, but not BDNF, delays photoreceptor loss in this hereditary retinal degeneration. Repeated injections maintain the protective effect. 相似文献
37.
38.
39.
Children of alcoholic parents in the community 总被引:1,自引:0,他引:1
The relationship between parental alcoholism and risk for maladjustment in the offspring was investigated in a community sample. Children of parents who met criteria for DIS/DSM-III alcohol abuse or dependence and children of parents who met criteria for ten other diagnoses were compared to children of "normal" parents. The data were obtained from the merging of the data banks of two major psychiatric epidemiology studies of the adult (17-64) and child (4-16) population of Puerto Rico. Results indicated that parental alcoholism in addition to creating an adverse family environment had an effect on the relative risk for maladjustment in the offspring (as measured by scores on the Child Behavior Checklist). Although previous studies have reported higher levels of externalizing behaviors in children of alcoholics, an increased risk for internalizing symptoms was observed in the children studied. Similar findings were obtained for the children of parents with other psychiatric disorders suggesting that the effects of parental alcoholism in children ages 4 to 16 may not be different from the consequences of parental mental illness per se. 相似文献
40.
Analysis of cancers missed at screening mammography. 总被引:16,自引:0,他引:16
Analysis of 320 cancers found in a screened population between August 1985 and May 1990 revealed 77 cancers that were "missed" at screening mammography. The missed lesions consisted of cancers incorrectly diagnosed after mammography (false-negative results) but visible in retrospect (n = 19); cancers correctly diagnosed after mammography but visible in retrospect on an earlier mammogram (n = 47); and cancers that went undetected by the first of two readers (n = 11). Missed lesions were categorized according to type of miss, reason for the miss, breast density, lesion features, and lesion location. The missed lesion were compared with 121 cancers that were correctly diagnosed at screening mammography. The missed cancers occurred in women with denser breasts (P = .046), were less likely to demonstrate malignant microcalcifications, and were more likely to demonstrate a developing opacity as an indication of cancer (P = .005). An understanding of the characteristics of missed lesions may be a valuable aid in increasing the sensitivity of screening mammography. 相似文献