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排序方式: 共有476条查询结果,搜索用时 15 毫秒
391.
Changes in bile acid composition in patients with primary biliary cirrhosis induced by ursodeoxycholic acid administration 总被引:12,自引:0,他引:12
A Crosignani M Podda P M Battezzati E Bertolini M Zuin D Watson K D Setchell 《Hepatology (Baltimore, Md.)》1991,14(6):1000-1007
We describe a detailed study of the effects of ursodeoxycholic acid administration on bile acid composition of the serum and bile of patients with primary biliary cirrhosis. Gas chromatography-mass spectrometry was used to analyze bile acids from 10 patients with primary biliary cirrhosis before and during ursodeoxycholic acid administration (500 mg/day, corresponding to approximately 8 mg/kg body wt), after group separation of the unconjugated and conjugated fractions by lipophilic anion exchange chromatography. These studies were directed at assessing whether the beneficial role of ursodeoxycholic acid in primary biliary cirrhosis was the consequence of a shift in the hydrophobic/hydrophilic balance of the bile acid pool and whether the hypercholeresis might result from the cholehepatic circulation of unconjugated ursodeoxycholic acid in bile. In basal conditions, the unconjugated bile acids accounted for only 5.5% and 2.5%, respectively, of the total bile acids of serum and bile; cholic acid was the major component of the conjugated fraction of serum and bile (56.0% +/- 4.0%, mean +/- S.E.M.), and ursodeoxycholic acid was present in only trace amounts. The conjugated fraction contained many unusual bile acids (representing 16.5% +/- 1.3% of total) including C25 bile acids, iso-chenodeoxycholic acid and several oxo-bile acids. After ursodeoxycholic acid administration biochemical indices of liver function all improved, but the proportions of the unconjugated bile acids in serum and bile did not significantly change.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
392.
This study aimed to obtain a better understanding of the relationship between circulating thyroxine (T4) concentrations and reproductive endocrine function in the ram. Mature Merino rams were thyroidectomized and supplemented with 0, 30, 100 and 300% of normal T4 for 10 weeks. Thyroidectomy had no apparent effect on spermatogenic function but interfered with sperm maturation, the latter being returned to normal by 30% T4 replacement. Circulating testosterone levels were reduced by thyroidectomy and restored to control levels by 30% T4; when T4 levels were supranormal (300%), circulating testosterone levels were again reduced. The lowered circulating testosterone levels in thyroidectomized rams occurred as a result of suppressed testosterone secretion from the testis, observed under basal conditions and also following LH-releasing hormone (LHRH) and human chorionic gonadotrophin injection. In thyroidectomized rams, sex hormone binding globulin (SHBG) levels were depressed without changes in testosterone clearance rate (TCR), while in rams with supranormal T4 levels, TCR was increased without changes in SHBG levels. Subnormal levels of T4 also restored to normal the reduced LH pulse frequency in thyroidectomized rams. Reduced LH pulse frequency, together with diminished LH release following LHRH injection in thyroidectomized rams, suggested effects of T4 at the hypothalamo-pituitary axis. The present study demonstrates that complete lack of thyroid hormones suppresses normal reproductive endocrine function in the ram, but that this can be restored to normal by 30% T4 replacement. The results support the theory that T4 plays a permissive rather than a regulatory role in reproductive function in males. 相似文献
393.
Acquired hypoprothrombinemia due to non-neutralizing antibodies to prothrombin: mechanism and management 总被引:1,自引:0,他引:1
A patient developed bleeding due to an acute acquired specific prothrombin deficiency. Unlike previously described patients, this patient had no evidence of an associated lupus anticoagulant. Prothrombin activity and antigen were decreased concordantly and the patient's plasma did not neutralize the activity of added prothrombin or interfere with its measurement by electroimmunoassay. Nevertheless, immunoelectrophoresis and experiments using 125I-prothrombin revealed a prothrombin-binding antibody. The residual prothrombin in the patient's plasma was in the form of a prothrombin-antibody complex. Administration of adrenal corticosteroids was associated with a rise in prothrombin activity and cessation of bleeding, but circulating prothrombin was still bound to the antibody. This suggests that non- neutralizing antibodies to prothrombin cause plasma prothrombin deficiency because of a rapid clearance of prothrombin-antibody complexes, which is slowed by adrenal corticosteroids. The antibody had a relatively low affinity for prothrombin (Kd 5 to 8 X 10(-7)) and was transient. It is possible, therefore, that the antibody arose not to prothrombin itself, but to an antigen sharing an epitope with prothrombin. 相似文献
394.
Many positive trends in the health of Americans continued into 1997. In 1997, the preliminary birth rate declined slightly to 14.6 births per 1000 population, and the fertility rate, births per 1000 women 15 to 44 years of age, was unchanged from the previous year (65.3). These indicators suggest that the downward trend in births observed since the early 1990s may have abated. Fertility rates for white, black, and Native American women were essentially unchanged between 1996 and 1997. Fertility among Hispanic women declined 2% in 1997 to 103.1, the lowest level reported since national data for this group have been available. For the sixth consecutive year, birth rates dropped for teens. Birth rates for women 30 years or older continued to increase. The proportion of births to unmarried women (32.4%) was unchanged in 1997. The trend toward earlier utilization of prenatal care continued for 1997; 82.5% of women began prenatal care in the first trimester. There was no change in the percentage with late (third trimester) or no care in 1997. The cesarean delivery rate rose slightly to 20.8% in 1997, a reversal of the downward trend observed since 1989. The percentage of low birth weight (LBW) infants rose again in 1997 to 7.5%. The percentage of very low birth weight was up only slightly to 1.41%. Among births to white mothers, LBW increased for the fifth consecutive year, to 6.5%, whereas the rate for black mothers remained unchanged at 13%. Much, but not all, of the rise in LBW for white mothers during the 1990s can be attributed to an increase in multiple births. In 1996, the multiple birth rate rose again by 5%, and the higher-order multiple birth rate climbed by 20%. Infant mortality reached an all time low level of 7.1 deaths per 1000 births, based on preliminary 1997 data. Both neonatal and postneonatal mortality rates declined. In 1996, 64% of all infant deaths occurred to the 7.4% of infants born at LBW. Infant mortality rates continue to be more than two times greater for black than for white infants. Among all the states in 1996, Maine, Massachusetts, and New Hampshire had the lowest infant mortality rates. Despite declines in infant mortality, the United States continues to rank poorly in international comparisons of infant mortality. Expectation of life at birth reached a new high in 1997 of 76.5 years for all gender and race groups combined. Age-adjusted death rates declined in 1997 for diseases of the heart, accidents and adverse affects (unintentional injuries), homicide, suicide, malignant neoplasms, cerebrovascular disease, chronic liver disease and cirrhosis, and diabetes. In 1997, mortality due to HIV infection declined by 47%. Death rates for children from all major causes declined again in 1997. Motor vehicle traffic injuries and firearm injuries were the two major causes of traumatic death. A large proportion of childhood deaths continue to occur as a result of preventable injuries. 相似文献
395.
B Bourke N Goggin D Walsh S Kennedy KD Setchell B Drumm 《Archives of disease in childhood》1996,75(3):223-227
Progressive familial intrahepatic cholestasis (PFIC) occurs in many communities and races. A form of PFIC in five children from two consanguineous marriages in an Irish kindred is described. In addition, a review of clinical information from the records of three deceased members of the kindred strongly implies that they also suffered from PFIC. The children had a history of neonatal diarrhoea, sepsis, and intermittent jaundice that ultimately became permanent. They suffered intractable pruritus and growth retardation. Despite evidence of severe cholestasis, serum gamma-glutamyl transferase and cholesterol were normal in these children. Sweat sodium concentration were raised in three children. Liver histology showed severe intrahepatic cholestasis and hepatocellular injury. Urinary bile acid analysis revealed a non-specific pattern consistent with chronic cholestasis. These children suffer from a form of PFIC remarkably similar to that occurring in members of the Byler kindred. 相似文献
396.
B Bourke N Goggin D Walsh S Kennedy K D Setchell B Drumm 《Archives of disease in childhood》1996,75(3):223-227
Progressive familial intrahepatic cholestasis (PFIC) occurs in many communities and races. A form of PFIC in five children from two consanguineous marriages in an Irish kindred is described. In addition, a review of clinical information from the records of three deceased members of the kindred strongly implies that they also suffered from PFIC. The children had a history of neonatal diarrhoea, sepsis, and intermittent jaundice that ultimately became permanent. They suffered intractable pruritus and growth retardation. Despite evidence of severe cholestasis, serum gamma-glutamyl transferase and cholesterol were normal in these children. Sweat sodium concentration were raised in three children. Liver histology showed severe intrahepatic cholestasis and hepatocellular injury. Urinary bile acid analysis revealed a non-specific pattern consistent with chronic cholestasis. These children suffer from a form of PFIC remarkably similar to that occurring in members of the Byler kindred. 相似文献
397.
398.
Bardhan KD; Nayyar AK; Royston C 《QJM : monthly journal of the Association of Physicians》1998,91(3):231-237
We studied 2119 patients presenting with duodenal ulcer as sole lesion, in
the period 1976-1993, the era of H2 receptor antagonist (H2RA) therapy,
prior to the introduction of Helicobacter pylori eradication. We used
clinical assessment and serial check endoscopy to investigate the incidence
of bleeding at presentation (group I, n = 286, 13.5%), the long-term
outcome in this group and in that presenting with pain alone (group II, n =
1833, 87%) with respect to ulcer recurrence and bleeding, and the effect of
H2RA maintenance therapy. Most patients were treated with H2RA, principally
cimetidine. In group I, seven patients died early on; 38 had urgent
surgery, of whom six died post- operatively. The remainder were treated;
five immediately re-bled, of whom three were operated on. On follow-up,
98/227 group I patients relapsed, 21 (21%) of whom rebled. Relapse in group
II was 1017/1668, with only 42 (4%) bleeding (p < 0.001). In patients
without maintenance treatment, relapse was markedly higher (50/78 group I,
529/742 group II), but group II still bled significantly less (20% group I
vs. 3% group II). Relapse on maintenance was: 48/149 with five (10%)
rebleeding in group I, and 488/926 with five (1%) bleeding in group II (p
< 0.001). Despite the introduction of H2RA therapy, patients presenting
with haemorrhage still have a risk of bleeding at ulcer relapse about
7-fold higher than that for those presenting with pain alone.
相似文献
399.
Pasta naturally enriched with isoflavone aglycons from soy germ reduces serum lipids and improves markers of cardiovascular risk 总被引:1,自引:0,他引:1
Clerici C Setchell KD Battezzati PM Pirro M Giuliano V Asciutti S Castellani D Nardi E Sabatino G Orlandi S Baldoni M Morelli O Mannarino E Morelli A 《The Journal of nutrition》2007,137(10):2270-2278
Most studies of soy and cholesterol have tested foods made from purified soy proteins containing mainly isoflavone glycosides. Fermented soy foods have mainly isoflavone aglycons and account for a high proportion of the soy protein source in Asia, where there is an inverse relationship between soy intake and serum cholesterol. The aim of this study was to compare a novel soy germ pasta, naturally enriched in isoflavone aglycons as a result of the manufacturing process, with conventional pasta for effects on serum lipids and other cardiovascular risk markers. In this randomized, controlled, parallel study design of 62 adults with hypercholesterolemia who consumed a Step II diet that included one 80-g serving/d of pasta, we measured serum lipids, high sensitivity C-reactive protein (hsCRP), urinary isoprostanes, and brachial artery flow-mediated vasodilatation at baseline and after 4 and 8 wk. The pasta delivered 33 mg of isoflavones and negligible soy protein and led to a serum isoflavone concentration of 222 +/- 21 nmol/L; 69% of subjects were equol producers. Soy germ pasta reduced serum total and LDL cholesterol by 0.47 +/- 0.13 mmol/L (P = 0.001) and 0.36 +/- 0.10 mmol/L (P = 0.002) more than conventional pasta, representing reductions from baseline of 7.3% (P = 0.001) and 8.6% (P = 0.002), respectively. Arterial stiffness (P = 0.003) and hsCRP (P = 0.03) decreased and improvements in all the above risk markers were greatest in equol producers. All measures returned to baseline when patients were switched to conventional pasta. In conclusion, pasta naturally enriched with isoflavone aglycons and lacking soy protein had a significant hypocholesterolemic effect beyond a Step II diet and improved other cardiovascular risk markers. 相似文献
400.
T Fotsis R Heikkinen H Adlercreutz M Axelson K D Setchell 《Clinica chimica acta; international journal of clinical chemistry》1982,121(3):361-371
We describe a capillary column gas chromatographic (GC) method for the analysis of lignans in urine. Lignans are excreted as mono-glucuronides which are first extracted on a small reversed-phase cartridge of octadecylsilane bonded silica (Sep-Pak C18) and thereafter isolated by anion exchange chromatography on DEAE-Sephadex A-25, prepared in the acetate form. Lignan mono-glucuronides are enzymatically hydrolysed and re-extracted on a Sep-Pak C18 cartridge. Quantification is carried out by capillary column GC of the trimethylsilyl ether derivatives. The specificity of the method was checked by GC/MS and the intra-assay coefficient of variation (CV) for the two lignans, enterolactone (trans-2,3-bis(3-hydroxybenzyl)butyrolactone) and enterodiol (2.3-bis(3-hydroxybenzyl)butane-1,4-diol) varied between 5 and 8%. Some values for the excretion of these lignans by normal men and women are presented. 相似文献