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51.
Zeiler CA Nemes S Holtz KD Landis RD Hoffman J 《The American journal of drug and alcohol abuse》2002,28(3):513-524
Differences in responses by ethnic group to The Drug Abuse Problem Assessment for Primary Care (DAPA-PC) were examined. The DAPA-PC is a self-administered (via computer), internet-based screening instrument with automatic scoring, patient profile for medical reference, and unique motivational messages. Results indicate differences between blacks and whites on responses to several items in these instruments. Differences in drug use were also found between the two ethnic groups in hair/urine results. The screening criteria for the DAPA-PC instrument appear to work for both the groups in this study. Differences in responses to alcohol and drug screening instruments by ethnic group should be taken into consideration when designing screening instruments for alcohol and/or other drug use and these instruments should be adapted for different ethnic groups, when necessary. The results of this study suggest that the DAPA-PC instrument is a useful alcohol and drug abuse screening instrument for both the blacks and whites in a primary care population. 相似文献
52.
53.
Hansson T Dahlbom I Hall J Holtz A Elfman L Dannaeus A Klareskog L 《Journal of pediatric gastroenterology and nutrition》2000,30(4):379-384
BACKGROUND: Highly discriminatory markers for celiac disease are needed to identify children with early mucosal lesions. The purposes of this study were to evaluate the clinical potential of circulating anti-tissue transglutaminase (tTG) immunoglobulin (Ig)A antibodies in the diagnosis of childhood celiac disease and to investigate the extent of autoreactivity of these antibodies. METHODS: Included in this retrospective study were samples from 22 children with biopsy-verified celiac disease, 23 control subjects with disease, and 22 healthy control subjects without any known gastrointestinal or inflammatory disorders. An enzyme-linked immunosorbent assay (ELISA) was used to measure the serum levels of IgA antibodies specific for human and guinea pig tTGs. All samples were also analyzed for antibodies to gliadin and endomysium (EMA). RESULTS: The concentrations of IgA specific for human and guinea pig tTGs correlated with the small intestinal villous structure and the serum levels of IgA EMA. The tTG ELISAs exhibited a high specificity and sensitivity for detection of untreated celiac disease. The human erythrocyte IgA tTG ELISA had the highest sensitivity (100%) and a specificity of 98%. The IgA EMA method had a sensitivity of 95% and the highest specificity (100%) of all tests. CONCLUSIONS: Our results provide additional support to the concept that anti-tTG IgA antibodies can be used as a highly discriminatory serologic marker for celiac disease and that measurements of these autoreactive antibodies may in the future be used as an alternative to the EMA test. 相似文献
54.
Wang WS; Fan FS; Hsieh RK; Chiou TJ; Lin JK; Lin TC; Yen CC; Liu JH; Hsu H; Chen PM 《Japanese journal of clinical oncology》1997,27(3):174-179
5-Fluorouracil in combination with leucovorin has been shown to be active
in therapeutic trials of metastatic colorectal carcinoma. In this study, we
administered these drugs to 72 patients with metastatic colorectal
carcinoma. Thirty-six of them without previous exposure to 5-fluorouracil
were treated with weekly bolus injections of 5-fluorouracil (425 mg/m2) and
leucovorin (25 mg/m2) supplemented with oral levamisole. Another 36
patients with or without prior 5-fluorouracil treatment received
5-fluorouracil 3,000 mg/m2 and leucovorin 300 mg/m2 in a 48-hour continuous
infusion every two weeks. Clinical efficacy and toxicity were assessed by
WHO criteria. Variables were tested for relations to response and survival
by univariate and multivariate analysis. The response rate was 19.4% in
weekly bolus arm and 13.9% in biweekly high-dose infusion arm (P = 0.527).
Median survivals in the two arms were 18.4 months (weekly) and 21 months
(biweekly) respectively (P = 0.708). Gastrointestinal side effects
including nausea, vomiting, diarrhea and mucositia were the major
toxicities of these regimens. By multivariate analysis, the only factor to
influence response rate was the site of metastases (P = 0.009). The only
factor to affect survival was performance status of the patient (P =
0.0001). We concluded that the two 5-fluorouracil based regimens are
well-tolerated and shown to have a response rate comparable with previous
reports of similar regimens in patients with metastatic colorectal cancer.
Only liver metastases seemed to have a better response to therapy.
Performance status is the most important prognostic factor in patients with
metastatic colorectal cancer.
相似文献
55.
Recent reports have demonstrated that the HIV-1 transactivator protein,tat, induces apoptosis in T-lymphocyte cell lines, as well as in peripheral blood mononuclear cells, and stimulates a cascade
of events resulting in up-regulation of the potent immunosuppressive cytokine, transforming growth factor-β (TGF-β). In this
study we evaluated the ability of TGF-β to mediatetat induced apoptosis in T-lymphocyte cell lines. T-cells treated exogenously with either TGF-β1 or a combination of tat and
pan-specific TGF-β neutralizing antibodies showed little change in the amount of apoptosis. When treated with pan-specific
TGF-β neutralizing antibodies, Jurkat cells that stably expresstat protein (Jurkat-tat) showed only a modest decrease in apoptosis, while CEM-TART cells (CEM T-cells expressing both HIV-1tat andrev) demonstrated little change in the amount of apoptosis. In conclusion, we have demonstrated that TGF-β does not play a significant
role in mediatingtat induced T-cell apoptosis. 相似文献
56.
The reliability of proton spectroscopic imaging in evaluating fatty infiltration of the liver was investigated in 35 subjects (12 healthy volunteers and 23 patients with fatty livers). With this modified spin-echo technique, fatty liver could be separated from normal liver both visually and quantitatively. On the opposed image, normal liver had an intermediate signal intensity, greater than that of muscle, whereas fatty liver had a lower signal intensity, equal to or less than that of muscle. In normal livers, the lipid signal fraction was less than 10%, while in fatty livers it was greater than 10% and usually exceeded 20%. With this technique, nonuniform fatty infiltration of the liver can be differentiated from hepatic metastases, and the technique may prove useful in the differentiation of some hepatic disorders. 相似文献
57.
Norepinephrine constricts the canine coronary bed via postsynaptic alpha 2-adrenoceptors 总被引:3,自引:0,他引:3
The effect of alpha 2-blockade (0.3 mg/kg i.v. rauwolscine) and alpha 1-blockade (1.2 mg/kg i.v. prazosin) on coronary constrictions induced by intracoronary injections of azepexole (B-HT 933, alpha 2-agonist, 0.1-10 microgram/kg), phenylephrine (0.3-3 microgram/kg) and norepinephrine (0.001-0.1 microgram/kg) were studied in dog hearts perfused in situ under beta-blockade. Constrictions by azepexole (antagonized by rauwolscine, yet resistant to prazosin and methysergide) demonstrated coronary alpha 2-adrenoceptors. Norepinephrine-induced constrictions were more attenuated (22-fold) by alpha 2-blockade than by alpha 1-blockade (2.6-fold) and thus were mediated mainly by activation of postsynaptic alpha 2-receptors. 相似文献
58.
Dr. med. R. Sörensen U. Holtz D. Banzer M. Khalil A. Hirner 《Cardiovascular and interventional radiology》1978,1(3):179-185
Twenty-two cases with communication of an artery and the portal vein or one of its tributaries are discussed. Four conditions
in which relatively significant arterio-portal shunts may exist can be differentiated: (1) angiodysplasias or arteriovenous
malformations, (3) traumatic and postoperative lesions, and (4) benign and malignant tumors. The significance of the portal
vein's early opacification during arteriographic examinations of the abdominal organs is discussed, and the findings are compared
to those reported in the literature. 相似文献
59.
60.