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1.
Thirty-four patients operated with sacrococcygeal teratoma in Sweden between 1978 and 1989 were reviewed. Twenty-five children were available for functional follow-up. The patients and their parents were interviewed for bowel and micturition habits. Fourteen patients from this number were subjected to anorectal manometry (56%). Fifteen children reported normal bowel habits (60%). In 10 patients (40%) soiling was observed. However, four of them were under 3 years of age and wearing diapers, which made the functional evaluation difficult. The manometries showed normal and resting tone and squeezing pressures in 10 patients and subnormal values in four patients who also had soiling problems. All investigated children showed normal rectoanal inhibition reflex. Twenty-one patients reported normal micturition, in four (16%) urinary incontinence was recorded. Two of the latter children required intermittent clean catheterization, one was on medication and the last one lives without any treatment. No difference in functional outcome was noted between patients with intrapelvic or extrapelvic tumor location. Retrospectively, it is not possible to know whether the observed functional outcome is due to tumor growth or the result of surgery. Preoperative clinical investigation and in some cases anorectal manometry and cystometry could theoretically resolve this problem.  相似文献   
2.
This study evaluated the influence of silymarin (SM) and polyphenolic fraction (PF) of silymarin on cholesterol absorption in rats fed on high cholesterol diet (HCD). HCD induced a remarkable increase in hepatic, plasma, VLDL and LDL cholesterol, a decrease in HDL cholesterol and an elevation in triacylglycerol (TAG) levels in plasma, VLDL and in the liver. SM and PF were administered as dietary supplements (1.0%) in HCD for 18 days. Intestinal cholesterol absorption was measured by dual-isotope plasma ratio method, which calculates percent of cholesterol absorption from the ratio of two labelled cholesterol doses, one given intragastrically (14C) and one intravenously (3H). Silymarin and PF significantly reduced cholesterol absorption in rats fed on HCD and caused significant decreases in plasma and VLDL cholesterol and content of cholesterol and TAG in the liver. The level of HDL cholesterol was significantly increased after silymarin, but not after administration of PF. The levels of TAG in plasma and VLDL were not affected by either silymarin or PF. These results suggest that the inhibition of cholesterol absorption caused by silymarin and its polyphenolic fraction could be a mechanism contributing to the positive changes in plasma cholesterol lipoprotein profile and in lipid content in liver.  相似文献   
3.
Lung function in atrial septal defect after heart surgery.   总被引:3,自引:0,他引:3  
Lung volume, indices of lung elasticity and airway patency were measured in 74 patients, 9-21 yr old (15.0 +/- 2.5 yr) with atrial septal defect (secundum type) from 2-11 (5.1 +/- 2.5) yr after successful surgical correction. Clinical condition in all patients was classified as excellent. Heart surgery was performed at the age of 4-14.8 (9.9 +/- 3.0) yr. Lung function abnormalities were found in 35 (47.3%) patients. Lung recoil pressure was significantly increased in 24 (32.4%) patients. The mean value of lung recoil pressure at 100% of total lung capacity reached 123 +/- 31% of the predicted value (P < 0.0001). Specific static compliance was within normal limits. Specific airway conductance was significantly reduced in 13 (17.6%) patients. Maximum expiratory flow at 25% of vital capacity was significantly reduced in 4 (5.4%) patients. Static lung volumes did not differ from reference values. Since various abnormalities of lung function tests (most frequently the tests suggested increased lung stiffness and obstruction of larger airways) were revealed in almost half of the studied children and adolescents after successful surgery for atrial septal defect, we propose to carry out lung function tests routinely as another criterion of health conditions in these patients.  相似文献   
4.
The risk of cardiotoxicity is the most serious drawback to the clinical usefulness of anthracycline antineoplastic antibiotics, which include doxorubicin (adriamycin), daunorubicin or epirubicin. Nevertheless, these compounds remain among the most widely used anticancer drugs. The molecular pathogenesis of anthracycline cardiotoxicity remains highly controversial, although the oxidative stress-based hypothesis involving intramyocardial production of reactive oxygen species (ROS) has gained the widest acceptance. Anthracyclines may promote the formation of ROS through redox cycling of their aglycones as well as their anthracycline-iron complexes. This proposed mechanism has become particularly popular in light of the high cardioprotective efficacy of dexrazoxane (ICRF-187). The mechanism of action of this drug has been attributed to its hydrolytic transformation into the iron-chelating metabolite ADR-925, which may act by displacing iron from anthracycline-iron complexes or by chelating free or loosely bound cellular iron, thus preventing site-specific iron-catalyzed ROS damage. However, during the last decade, calls for the critical reassessment of this “ROS and iron” hypothesis have emerged. Numerous antioxidants, although efficient in cellular or acute animal experiments, have failed to alleviate anthracycline cardiotoxicity in clinically relevant chronic animal models or clinical trials. In addition, studies with chelators that are stronger and more selective for iron than ADR-925 have also yielded negative or, at best, mixed outcomes. Hence, several lines of evidence suggest that mechanisms other than the traditionally emphasized “ROS and iron” hypothesis are involved in anthracycline-induced cardiotoxicity and that these alternative mechanisms may be better bases for designing approaches to achieve efficient and safe cardioprotection.  相似文献   
5.
1. The effects of nifedipine (Nif) and its illuminated nitroso product nitrosopine (NTP) were investigated on lipid peroxidation, KCl elevated smooth muscle tension, and ionic currents of single smooth muscle cells. 2. Illumination of Nif at 400-700 nm within 24-48 h changed it completely to a potent antioxidant, NTP. 3. Nif relaxed the KCl-induced contractions of guinea-pig taenia caeci and rat aorta and reduced the amplitude of the evoked inward Ca2+ current of taenia caeci cells in a concentration-dependent manner. NTP (up to 100 microM) was ineffective in this respect. Pretreatment by NTP (10 microM) did not affect the actions of Nif. 4. The evidence suggests that NTP, generated by day-light illumination from Nif, exerts antioxidant activity but is devoid of voltage-dependent Ca2+ channel (VDC) blocking property and does not interfere with the action of Nif on the smooth muscle cell membrane VDC.  相似文献   
6.
It is unresolved whether elevated homocysteine in coronary artery disease (CAD) is the cause of arteriosclerosis or its consequence. In contrast, genetic variants of enzymes that metabolize homocysteine cannot be altered by arteriosclerosis. Consequently, their association with CAD would permit to imply causality. We modeled by regression analysis the effect of 11 variants in the methionine cycle upon CAD manifestation in 591 controls and 278 CAD patients. Among the examined variants only the carriership for the c.844ins68 in the cystathionine beta-synthase (CBS) gene was associated with a significantly lowered risk of CAD (OR=0.56; 95% CI=0.35-0.90 in the univariable, and OR=0.41, 95% CI=0.19-0.89 for obese people in the multivariable analysis, respectively). Healthy carriers of the c.844ins68 variant exhibited, compared to the wild type controls, significantly higher postload ratios of blood S-adenosylmethionine to S-adenosylhomocysteine (61.4 vs. 54.9, p=0.001) and of plasma total cysteine to homocysteine (8.6 vs. 7.3, p=0.004). The changes in these metabolites are compatible with an improved methylation status and with enhanced activity of homocysteine transsulfuration. In conclusion, the coincidence of clinical and biochemical effects of a common c.844ins68 CBS variant supports the hypothesis that compounds relating to homocysteine metabolism may play role in the development and/or progression of CAD.  相似文献   
7.
Both cardiac troponin T (cTnT) and cardiac troponin I (cTnI) are considered to be reliable biomarkers with sufficient sensitivity and specificity for cardiac injury in the majority of laboratory animals. The aim of our study was to compare the diagnostic performance of cTnT and cTnI in three groups of rabbits: 1) control (saline 1 ml/kg i.v.); 2) Salicylaldehyde Isonicotinoyl Hydrazone--SIH (50 mg/kg, once weekly, i.p.; partially dissolved in 10% Cremophor solution); 3) 10% Cremophor solution in water (2 ml/kg i.v.). The drugs were given once a week, 10 administrations. The concentration of cTnT was measured using Elecsys Troponin T STAT Immunoassay (Roche). The concentration of cTnI was measured using AxSYM Troponin I (Abbott). The linear regression model was applied to see if there is a dependence between cTnT and cTnI. The coefficient of determination was not acceptable in all groups. The highest value of R2 was found in the control group (R2 = 0.424). We may conclude that in rabbits meaningful dependence between cTnT and cTnI was not found. According to our long-term experiences cTnT seems to be more suitable cardiomarker in rabbits in comparison with cTnI where the data are characterized by the large scatter.  相似文献   
8.
Two different hapten designs have been suggested for production of generic antibodies. The first approach was based on the immunogen prepared by conjugating simazine mimic to carrier proteins through the Cl position of the s-triazine herbicide. For sulfonylurea herbicides a single ring hapten strategy was designed in order to produce antibodies with dominant selectivity towards arylsulfonyl or triazine moieties of metsulfuron-methyl. The best monoclonal antibody raised against simazine-derived hapten mimic (clone B10/B8/D2) exhibited in direct ELISA a broad pattern for a group of methylthio and methoxy s-triazines. Cross-reactivities based on simazine ( = 100%) were 417, 125, 25, 50, 28, 42 and 11% for simetryn, ametryn, prometryn, terbutryn, aziprotryn, atraton and atrazine, respectively. The superiour generic pattern was found for monoclonal antibody raised against s-triazine moiety of metsulfuron-methyl herbicide (clone 2C8/C8). This antibody showed in indirect ELISA the cross-reactivity values 100, 142, 95, 60, 40, 167, 83 and 21% for metsulfuronmethyl, cinosulfuron, triasulfuron, primisulfuron-methyl, thifensulfuron-methyl, chlorsulfuron and prosulfuron and tribenuron-methyl, respectively. The assays using both monoclonal and polyclonal antibodies operated within the ppt-ppb calibration ranges.  相似文献   
9.
Two sensitive methods, RT-PCR with phenol-extracted RNA or Triton X-100-released RNA and immunocapture RT-PCR (IR-RT-PCR) were used for the detection of Beet yellows virus (BYV) in young and old leaves of Tetragonia expansa and sugar beet (Beta vulgaris) and in sugar beet roots. Four oligonucleotide primer pairs proved suitable for the detection of BYV. The release of BYV RNA with Triton X-100 was shown to be a very effective and easy as compared to isolation of total RNA by phenol extraction with the same or higher sensitivity of subsequent PCR. Using the Triton X-100 release of RNA and IC-RT-PCR the sensitivity of detection was so high that pg amounts of BYV RNA occurring in dilutions up to 10(-6) of saps from young Tetragonia and sugar beet leaves could be detected.  相似文献   
10.
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