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11.
Franciszek Burdan Zofia Siezieniewska Ryszard Maciejewski Barbara Madej Elzbieta Radzikowska Zbigniew Wojtowicz 《Experimental and toxicologic pathology》2002,53(6):453-459
The aim of the study was to establish the influence of short-time omeprazole administration on liver function and morphology. Omeprazole was administered intraperitoneally, twice daily, for 3 days to male Wistar rats in two doses: 0.571 mg/kg and 5.71 mg/kg. Control animals were treated with physiological saline. Half of the animals were sacrificed 12 hours after the last injection. The remaining rats were raised for another 6 weeks, without any xenobiotics, and sacrificed on the 47th day of the experiment. The activity of free and bound fractions of hepatic acid phosphatase, beta-galactosidase, beta-N-acetyl-glucosaminidase, cathepsin B, D and L, lipase, and sulphatase were determined spectrophotometrically in homogenates of the liver. The liver sections were examined by light microscopy with hematoxylin-eosin, azan, and periodic acid-Schiff stains. Marginally significant (p < 0.1) differences in activity of free sulphatase fraction, and free and bound fractions of beta-galactosidase were found in animals exposed to the higher dose of omeprazole and sacrificed 12 hours after the last injection. Enzymatic profiles were normalised during the next 6 weeks. Histological evaluation revealed small degenerative and adaptive changes in all examined groups. It could be concluded that observed differences of hepatic lysosomal enzyme activities were the result of accompanied chemical-induced peritonitis as previously reported, and not a direct drug-toxic effect. 相似文献
12.
从兔网织红细胞提纯的红细胞分化调节因子(erythroid differentiation factor,EDF),能对体外培养的自发转化成纤维细胞系L929及人鼻咽癌细胞系KB产生作用。当EDF剂量为0.10μg/ml时,可引起L929细胞形态发生改变,并有细胞核固缩现象。第2d的细胞生长抑制率为64.86%,软琼脂集落形成率为0;第5d时细胞增殖为负值。~3H-TdR掺入率明显降低。EDF剂量为0.15μg/ml时,对KB细胞生长已有抑制作用。EDF剂量达0.30μg/ml时,生长抑制明显。以上结果证明了EDF对恶性细胞具有增殖抑制作用。这种作用对不同种类细胞敏感性不同,并且与剂量呈正相关。 相似文献
13.
Chemically induced mutants of an I-Ak,d expressing antigen-presenting B-cell--B-lymphoma hybridoma have recently been generated by immunoselection in vitro and were found to possess alterations in some of their serologically and functionally defined I-Ak region dependent functions. In order to identify at the structural level the origin of the differences in serological and functional properties of these mutants, I-Ak molecules from several of these mutant hybridomas were compared biochemically to wild-type I-Ak polypeptides by two-dimensional gel electrophoresis and high-pressure liquid chromatographic tryptic peptide analyses. Two-dimensional gel electrophoresis indicated that no major structural alterations, resulting in changes in mol. wt or charge, had occurred in the Ak alpha or Ak beta polypeptides from the mutant cells. Likewise, Ak alpha peptide maps of the mutants were indistinguishable from the normal Ak alpha peptide maps. However, two of the three mutants studied did exhibit one additional peptide in their Ak beta peptide maps. These results suggest that the major deficiencies in T-cell-activating functions of these mutants are a result of a limited alteration in the Ak beta polypeptide primary structure. 相似文献
14.
The familial prevalence in second-degree relatives of patients with anxiety neurosis (panic disorder) 总被引:1,自引:0,他引:1
A family history study of second-degree relatives of 19 patients with anxiety neurosis (panic disorder) and 19 controls showed a morbidity risk of 9.5% among the former compared with 1.4% among the latter. These risks were approximately half those found among first-degree relatives. Female relatives were at higher risk for anxiety neurosis. The risk for other psychiatric illnesses did not differ between the relatives of anxiety neurosis and controls. 相似文献
15.
The present study was designed to investigate the relationship between intra-and inter-individual differences in arousal level and performance on both critical flicker fusion frequency and figural reversal tasks. Forty male undergraduate Ss were used. Electrical skin conductance was used as the indicant of arousal level. For the intra-individual comparisons white noise was used to increase the Ss’arousal levels. Significant inverted U-shaped relationships were found between both flicker fusion thresholds and rates of figural reversal and skin conductance between individuals. A significant curvilinear relationship was found between rates of figural reversal and level of conductance within individuals. No significant curvilinear relationship was found between flicker fusion thresholds and level of conductance within individuals. 相似文献
16.
Genome of the European elk papillomavirus (EEPV) 总被引:1,自引:0,他引:1
The genome of the European elk papillomavirus (EEPV) was found to be 8,095 base pairs (bp) long and its genetic organization was similar to that of other papillomaviruses. Ten open reading frames (ORFs), designated E1-E7 and L1-L3, were identified in the genome, all located on one strand. The presence of the L3 ORF is rare among the papillomaviruses and to date has only been identified in the genomes of EEPV, the deer papillomavirus (DPV) and the Cottontail papillomavirus (CRPV). The ORF is well conserved beteeen DPV and EEPV with regard to both length and sequence. Potential promoter regions were identified at the 5-end of the E6 ORF, at the 3-end of the E1 ORF and downstream of the L1 ORF. Furthermore, two potential polyadenylation signals were found, one located in the long control region (LCR), downstream of the L1 ORF, and another preceding the L2 ORF. The EEVP genome is closely related to the genome of the DPV, the most highly conserved regions being ORFs E1 (70%), E5 (69%), and L1 (74%). 相似文献
17.
In the search for a serology tool for the diagnosis of nonpatent as well as patent infections with Oesophagostomum dentatum in pigs a water-soluble, unglycosilated antigen of about 30 kDa specific for the third-stage larvae of the parasite was purified
by ion-exchange chromatography. In Western blots, the antigen was first detected by antibodies at day 7 postinfection. Cross-reactivity
with O. quadrispinulatum, Ascaris suum, or Trichuris suis was not detected. It is suggested that this protein is a suitable tool for the species-specific serodiagnosis of O. dentatum infection in pigs.
Received: 15 June 1998 / Accepted: 28 September 1998 相似文献
18.
C Arbesman I L Bernstein C W Bierman J S Bocles R Katz P L Lieberman K Mattucci E O Meltzer E Middleton J Noyes D S Pearlman H L Pence R G Slavin S L Spector 《The Journal of allergy and clinical immunology》1983,71(6):597-603
Fluocortin butyl (FCB) is a newly synthesized corticosteroid with a high ratio of topical to systemic activity. FCB was studied in a multi-center, double-blind, placebo-controlled trial of therapy of perennial rhinitis. The study was conducted between January and May 1981. Patients evaluated suffered from either chronic allergic or chronic nonallergic rhinitis or both. A total of 306 patients from 16 investigative centers were evaluated by comparing FCB to placebo. Three separate dosage regimens were employed. Patients received a total daily dose of 2, 4, or 8 mg. FCB was found to be an effective therapeutic agent. It reduced symptoms of nasal congestion, rhinorrhea, postnasal drainage, and sneezing. It also markedly reduced the use of concomitant medications (chlorpheniramine maleate and/or pseudoephedrine). Relief of symptoms was noted as early as the first week of therapy, and the degree of improvement increased progressively during the study. There was little difference between the relief produced by the 4 mg and 8 mg regimens. Both of these were superior to the 2 mg regimen. The drug was well tolerated; no significant side effects were noted. 相似文献
19.
The present experiment explored the utility of finger pulse volume (FPV) as a measure of anxiety. Subjects were exposed to either a threatening or nonthreatening situation, and indices of physiological arousal (pulse rate (PR) and FPV) and self-report of anxiety (Affect Adjective Checklist (AACL)) were collected. Results indicated that FPV was responsive to changes in experimentally induced anxiety and significantly correlated with PR and AACL, although the strength of these relationships was not substantial. Relevance for psychophysiological theory and the clinical observation of anxiety is discussed. 相似文献
20.
The emigratory behavior and locomotor activity of yellow-eyed (y/y), wildtype (+/+), and heterozygous (+/y) house flies was examined at 8 fc (86 lx) and 1600 fc (17,223 lx) light intenstities. At 8 fc, emigration rate and activity of the y/y flies was similar to that of the +/+ and +/y flies. However, at 1600 fc, the y/y flies emigrated at twice the rate and showed an activity of about one-third that of the other genotypes. The behavior of the +/+ and +/y flies remained similar regardless of the experimental design or light intensity. The excessive neural stimulation by high-intensity light resulting from reduced shielding pigments led to behavioral modifications in the visual and tactile responses of the y/y flies.This research was supported in part by grants from the CUNY Faculty Research Award Program (No. 1103) and NIH Biomedical Research Support Grant 5-S05-R-07064. 相似文献