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1.
There is a great body of evidence linking a high fat diet with the formation of gallstones. However, the effect of fat per se on obstructive liver damage (not involving gallstone formation) has not been assessed. The aim of this work was to study the effect of a high fat diet on liver damage induced by bile duct ligation in rats. Male 21-day-old Wistar rats were divided into two groups: group 1 received standard Purina chow diet 5001 containing 4.5% fat, group 2 received Purina chow diet 5001 enriched with 33% pork fat. Animals were allowed food and water ad libitum for 5 weeks. Obstructive jaundice was induced by double ligation and division of the common bile duct. The animals were sacrificed 1 week after biliary obstruction. Control animals were sham operated. Serum bilirubins and alkaline phosphatase, gamma-glutamyl transpeptidase and glutamic pyruvic transminase enzyme activities increased by biliary obstruction. Glycogen content decreased in the bile duct-ligated rats. These effects were more important in the group fed a 33% fat diet. Our results show that a high animal fat diet increases liver damage in experimental biliary obstruction in rats. Owing to our experimental design (bile duct ligation), the effect of a high fat diet cannot be attributed to an increase in the formation of gallstones but a direct effect must be considered. The mechanism by which fat augmented liver damage can be associated with an increase of total bile content and its toxicity.  相似文献   

2.
Human blood monocytes are known to react with hydrocortisone in vitro to produce a factor which stimulates polymorph migration. This study shows that the polymorph migration stimulator (PMS) is generated only by steroids with glucocorticoid activity. The interaction between steroid and monocytes is dependent on protein synthesis. Serum is necessary for the expression of the activity of the factor, but the steroid-monocyte reaction can occur in the absence of serum. The stimulatory effect on migration appears to be specific for polymorphs and does not affect mono-nuclear leucocytes. In addition to blood monocytes, spleen and bone marrow cells also react with corticosteroids to produce the polymorph migration stimulator.  相似文献   

3.
The effects of the vitamins dl-alpha-tocopherol, ascorbic acid and beta-carotene, free radical scavengers and lipid peroxidation inhibitors, were analyzed in male Wistar rats made goitrous by feeding a low iodine diet (< 20 micrograms iodine/kg) and perchlorate (1% in drinking water) for 4, 8, 16, and 32 days. Groups of control or goitrous rats received for at least 16 days before killing a diet containing 0.6% vitamin E (as dl-alpha-tocopherol acetate), 1.2% vitamin C (ascorbic acid) and 0.48% beta-carotene, either simultaneously (vitamin cocktail) or separately. This treatment led to a 5-fold increase of vitamin E in the thyroid gland, a 24-fold increase in the liver and a 3-fold increase in the plasma. In control rats, vitamin cocktail administration increased slightly the thyroid weight with little changes in thyroid function parameters. During iodine deficiency, administration of the vitamin cocktail or vitamin E alone reduced significantly the rate of increase in thyroid weight, and DNA and protein contents, as well as the proportion of [3H]thymidine labeled thyroid follicular cells, but not that of labeled endothelial cells. Plasma tri-iodothyronine, thyroxine, TSH levels, thyroid iodine content and concentration as well as relative volumes of glandular compartments were not modified. The proportion of necrotic cells rose from 0.5% in normal animals to about 2% after 16 days of goiter development. No significant protective effect of the vitamins was observed. These results suggest that these vitamins, particularly vitamin E, modulate one of the regulatory cascades involved in the control of thyroid follicular cell growth, without interfering with the proliferation of endothelial cells.  相似文献   

4.
We have characterized the histamine releasing effects of lectins extracted from Brazilian beans, in comparison to concanavalin A, in hamster cheek pouch cell suspensions containing mast cells. The lectins from Dioclea virgata, Canavalia brasiliensis, and Dioclea rostrata induce histamine release in a similar manner to concanavalin A, but appear to differ in potency and efficacy. The effects depended on the temperature, pH, and metabolic energy, demonstrating the non-cytotoxic nature of the histamine release. It is suggested that the lectins studied act by the same mechanism as concanavalin A (interacting with sugars in the antibodies bound to the mast cells), since high concentrations of glucose inhibit the histamine release. The lectins at high concentrations quench the histamine release. This suppression is reversed by increasing calcium concentration, suggesting that the lectins bind to the calcium that is essential for the secretion, thereby confirming and extending our previous data using the lectin from Dioclea virgata in rat peritoneal mast cells.  相似文献   

5.
The combination of fast MR sequences and rapid i.v. injection of paramagnetic contrast media provides information on cerebral perfusion. MR-perfusion imaging primarily depicts the relative cerebral blood volume. The aim of this study was to test whether MR-perfusion imaging with a clinical MR scanner using a standard 2D-FLASH sequence provides clinically relevant information on patients with cerebrovascular diseases and brain tumors. Brain infarctions, lesions in cerebral microangiopathy and occlusions of the carotid artery with very poor collateralization showed definite differences in perfusion imaging compared with normal controls. However, our results show that acceleration of the imaging sequence and optimization of the contrast bolus and data processing are prerequisites for the clinical use of this method, which in principle may provide information on the absolute cerebral blood volume and even blood flow.  相似文献   

6.
The main aim of the present novel reanalysis of archival data was to compare the time to remission during 12 weeks of treatment of chronic depression following antidepressant medication (n = 218), psychotherapy (n = 216), and their combination (n = 222). Cox regression survival analyses revealed that the combination of medication and psychotherapy produced full remission from chronic depression more rapidly than either of the single modality treatments, which did not differ from each other. Receiver operating characteristic curve analysis was used to explore predictors (treatment group, demographic, clinical, and psychosocial) of remission. For those receiving the combination treatment, the most likely to succeed were those with low baseline depression (24-item Hamilton Rating Scale for Depression [HRSD; M. Hamilton, 1967] score  相似文献   

7.
Prior research suggested that pride is recognized only when a head and facial expression (e.g., tilted head with a slight smile) is combined with a postural expression (e.g., expanded body and arm gestures). However, these studies used static photographs. In the present research, participants labeled the emotion conveyed by four dynamic cues to pride, presented as video clips: head and face alone, body posture alone, voice alone, and an expression in which head and face, body posture, and voice were presented simultaneously. Participants attributed pride to the head and face alone, even when postural or vocal information was absent. Pride can be conveyed without body posture or voice. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

8.
Surface energies of carbopol, chitosan, hydroxypropyl cellulose (HPC) and poly(HEMA) were assessed from contact angle and surface tension experiments. The surface energy was considered in terms of an apolar Lifshitz-van der Waals term and a polar acid-base term, which in turn is divided into electron donor and electron receptor (Lewis acid-Lewis base) contributions. Using these surface energy terms the interaction of dry and hydrated polymer with mucin in the presence of either artificial gastric or intestinal fluid, or saline was predicted. The predictions were related to measured forces of detachment. There was a significant difference between the surface energy on dry and hydrated HPC and also for carbopol; for the other polymers either the surface energy of the hydrated material was not detectable, or the effect of hydration was minimal. There were good correlations between mucoadhesive strength and the calculated free energies of interaction between mucin and polymer in the presence of each of the fluids, for each individual polymer. Thus, two trends were observed, one for unionisable and the other for ionisable polymers. It is argued that the increased mucoadhesion seen with ionisable polymers (compared with the predicted value based on results of unionisable polymers) is a direct result of the ionic interaction. No attempt has been made to correct for the ionisation effect, but the surface energy predictions provide insight into the mechanism of the mucoadhesion process. This approach is useful for understanding and predicting interactions between different materials and biological components.  相似文献   

9.
After discussion of the legal basis for licencing and release of sera and vaccines the procedures practiced in Western Germany and in the USA are compared. The value of specified tests required in routine control for safety and efficacy of biological products is discussed. The best means to control biological products in the opinion of the author is a continuous quality control during the entire process of production.  相似文献   

10.
3- and 10-mo follow-up data on 48 volunteers in a smoking withdrawal program indicate that neither hypnosis alone nor group contact alone yielded satisfactory results; however, the combined use of these procedures yielded a fairly high success rate (56.25 and 50% for the 3- and 10-mo assessments, respectively). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

11.
A new antibiotic, named laterosporamine, was isolated from the culture broth of Bacillus laterosporus 340-19. The antibiotic is active against Gram-positive and Gram-negative bacteria in vitro and in vivo. It is a water-soluble basic substance, positive to ninhydrin, SAKAGUCHI'S and DRAGENDORFF'S reagents. A non-peptidic structure with an approximate empirical formula C17H35N7O4 was suggested.  相似文献   

12.
Blood group ABO antigens are known to be carried by several platelet glycoproteins (GP), e.g. GPIb, GPIIa, GPIIb, GPIIa and PECAM. Beside these proteins, we recently observed that blood group A antigen was also expressed on some other uncharacterized platelet proteins (70-90 kDa) having electrophoretic mobilities closely resembling those of GPIV and GPV. These findings prompted us further to characterize these latter ABO-expressing platelet proteins. By antigen capture ELISA, wherein the monoclonal antibodies (mAbs) CLB-IVC7 and CLB-SWI6 were used to hold the corresponding antigens GPIV and GPV, human anti-A specifically bound to these proteins derived from A1-platelets; neither GPIV nor GPV derived from A2-, B- or O-platelets bound anti-A. In a Western blot assay using immunoprecipitated GPIV and GPV as antigens, mAb anti-A immunostained GPIV and GPV precipitated from A1, but not from A2 and O platelets. These results conclusively demonstrate that blood group A antigen is expressed on platelet GPIV and GPV.  相似文献   

13.
Red blood cells from HBSAg-positive blood were washed in the Fenwal Elutramatic, Haemonetics Processor 15, or the IBM Blood Processor with sodium chloride solutions, or in the Huggins Cytoglomerator with sugar solutions. The Fenwal Elutramatic and IBM Blood Processor were the most efficient washing systems, the Haemonetics Processor 15 was less efficient, and the Huggins Cytoglomerator was the least efficient in removing the HBSAg. Washing to remove the HBSAg from red blood cells containing 40 per cent W/V glycerol in an ionic medium was more efficient than washing HBSAg from liquid-stored red blood cells or red blood cells containing 20 per cent W/V glycerol. The original and modified dilution/agglomeration wash cycles used in the Huggins Cytoglomerator were not able to remove the HBSAg from units of blood that were radioimmune assay (RIA) positive and counterelectrophoresis (CEP) negative. Freezing had no effect on the removal of the HBSAg in vitro, whereas the concentration of 40 per cent W/V glycerol in the red blood cells that were washed did. HBSAg was not found in the amorphous debris remaining in the polycarbonate disposable bowl used in the Haemonetics Processor 15 or in the microaggregates remaining in washed red blood cells.  相似文献   

14.
P Bégué 《Canadian Metallurgical Quarterly》1998,182(3):567-77; discussion 577-9
The combination vaccines are very useful to reduce the number of contacts required to immunize a child fully and to improve the vaccine coverage. Recently the new combinations between Haemophilus Influenzae vaccine (PRP-T) and pertussis vaccines in D-T-P (IVP) combined vaccines have suggested interferences with immunogenicity for PRP-T vaccines. The interference for pertussis antibodies is not significative. The depression of antiPRP antibodies is shown with the whole-cell pertussis vaccine, but the level of antibodies is related to a good protective efficacy. Inversely, when PRP-T vaccine is combined with acellular pertussis vaccines, the antibodies levels are lower, especially the number of children with a level higher than 1 mcg/ml. At the present time, these combinations between PRP-T vaccines and acellular pertussis vaccines are not recommended for primary immunization in infants in France. Such constations emphasize the necessity to perform wide comparative trials to test immunogenicity for all the next combinations between old and new vaccines. A decrease in immunogenicity of combination vaccines is acceptable as long as protective efficacy is preserved. It is possible that the growing number of new vaccines to combine will be limited to keep a clinical efficacy.  相似文献   

15.
A new antibiotic, aplasmomycin, which inhibits growth of Gram-positive bacteria including myobacteria in vitro, and plasmodia in vivo was obtained from a strain of Streptomyces griseus isolated from shallow sea sediment in Sagami Bay. The antibiotic forms colorless needle-like crystals and has a molecular formula of C41H60O14Na. Based on its physical and chemical properties, aplasmomycin was concluded to be a new antibiotic. The antibiotic was produced in selected media devised to relate to a marine environment.  相似文献   

16.
17.
Three topics are considered in this article: (1) the sociology and politics of the social and behavioral sciences; (2) psychology as a socially constructed activity involving narrative, rhetoric, and ideology; and (3) the matter of methods. Drawing on various sources of inspiration, from scientists and poets alike, the authors propose that psychologists confidently craft an array of indigenous methods that bridge the sciences and humanities, become self-critically aware of the values embedded in their scholarly and implemental praxis, and create both personal and institutional space for living "at the dangerous edge of things." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
19.
BACKGROUND: The value of intensive combination therapy in early rheumatoid arthritis is unproven. In a multicentre, double-blind, randomised trial (COBRA), we compared the combination of sulphasalazine (2 g/day), methotrexate (7.5 mg/week), and prednisolone (initially 60 mg/day, tapered in 6 weekly steps to 7.5 mg/day) with sulphasalazine alone. METHODS: 155 patients with early rheumatoid arthritis (median duration 4 months) were randomly assigned combined treatment (76) or sulphasalazine alone (79). Prednisolone and methotrexate were tapered and stopped after 28 and 40 weeks, respectively. The main outcomes were the pooled index (a weighted change score of five disease activity measures) and the Sharp/Van der Heijde radiographic damage score in hands and feet. Independent health-care professionals assessed the main outcomes without knowledge of treatment allocation. FINDINGS: At week 28, the mean pooled index was 1.4 (95% CI 1.2-1.6) in the combined treatment group and 0.8 (0.6-1.0) in the sulphasalazine group (p < 0.0001). At this time, 55 (72%) and 39 (49%) patients, respectively, were improved according to American College of Rheumatology criteria. The clinical difference between the groups decreased and was no longer significant after prednisolone was stopped, and there were no further changes after methotrexate was stopped. At 28 weeks, the radiographic damage score had increased by a median of 1 (range 0-28) in the combined-therapy group and 4 (0-44) in the sulphasalazine group (p < 0.0001). The increases at week 56 (2 [0-43] vs 6 [0-54], p = 0.004), and at week 80 (4 [0-80] vs 12 [0-72], p = 0.01) were also significant. Further analysis suggests that combined therapy immediately suppressed damage progression, whereas sulphasalazine did so less effectively and with a lag of 6 to 12 months. There were fewer withdrawals in the combined therapy than the sulphasalazine group (6 [8%] vs 23 [29%]), and they occurred later. INTERPRETATION: This combined-therapy regimen offers additional disease control over and above that of sulphasalazine alone that persists for up to a year after corticosteroids are stopped. Although confirmatory studies and long-term follow-up are needed, this approach may prove useful in the treatment of early rheumatoid arthritis.  相似文献   

20.
Myoglobin isolated from skeletal muscle of the platypus contains 153 amino acid residues. The complete amino acid sequence has been determined following cleavage with cyanogen bromide and further digestion of the four fragments with trypsin, chymotrypsin, pepsin and thermolysin. Sequences of the purified peptides were determined by the dansyl-Edman procedure. The amino acid sequence showed 25 differences from human myoglobin and 24 from kangaroo myoglobin. Amino acid sequences in myoglobins are more conserved than sequences in the alpha- and beta-globin chains, and platypus myoglobin shows a similar number of variations in sequence to kangaroo myoglobin when compared with myoglobin of other species. The date of divergence of the platypus from other mammals was estimated at 102 +/- 31 million years, based on the number of amino acid differences between species and allowing for mutations during the evolutionary period. This estimate differs widely from the estimate given by similar treatment of the alpha- and beta-chain sequences and a constant rate of mutation of globin chains is not supported.  相似文献   

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