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41.
S Otto  T Baum  F Keller 《Annals of anatomy》2006,188(2):153-158
The aim of the current study was to find out whether there are sex-dependent differences in the relative number of elastic fibres in human heart valves. Twenty-six aortic valves, 26 mitral valves, 33 pulmonary valves and 28 tricuspid valves of both sexes were obtained at autopsy from newborn to 89-year-old patients who died of noncardiac diseases. The quantitatively morphometric investigations were carried out on conventionally stained (Resorcinfuchsin) histological sections. The results were qualitatively examined with immuno-histochemically marked (anti-elastin antibodies) histological sections. Earlier examinations by Leutert [1976. Z. Gesamte Inn. Med. 31, 97-104] showed that the atrioventricular valves have the following layers: endothelium, atrial fibroelastic tissue (S1), fibrous tissue, ventricular fibroelastic tissue (S2) and endothelium. In our study, the ventricular side of the semilunar valves corresponds to side S1, whereas the vessel side corresponds to side S2. Three regions of interest were examined on each side of the valves: base, mid and tip. The number of elastic fibres per measuring area for all four human heart valves was significantly higher (p < 0,001) in fibroelastic tissue of side S1 than in fibroelastic tissue of side S2. Neither on side S1 nor on side S2 were there significant gender-related differences in the relative number of elastic fibres per measuring area. The results suggest a characteristic distribution of the elastic fibre system which is not sex-dependent but closely related to the function of the heart valves.  相似文献   
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43.
Male genital oedema can be defined as swelling or the appearance of swelling of the scrotum and/or the penile shaft and prepuce. Despite the various causes of genital oedema reported in the published work, a concise approach to the evaluation and management has not been sufficiently addressed.  相似文献   
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45.
BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.  相似文献   
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Anti-mitochondrial antibodies (anti-M7) in sera from patients with dilated cardiomyopathy and myocarditis recognize, besides mitochondrial antigens, bacterial sarcosine dehydrogenase. The common target antigen was identified as the covalently bound FAD of mitochondrial and bacterial flavoenzymes. Thus, anti-M7-positive serum reacted on Western blots exclusively with covalently flavinylated enzymes. The antigenic specificity of anti-M7 sera was reproduced by an antiserum raised in rabbits with 6-hydroxy- D -nicotine oxidase. The heart mitochondrial membrane antigen recognized by anti-M7 serum was identified as the flavoprotein subunit of succinate dehydrogenase, the antigens in rat liver mitochondrial matrix as the flavoenzymes dimethylglycine dehydrogenase and sarcosine dehydrogenase. Anti-M7 serum contained a specific anti-flavoenzyme antibody fraction. Nanomolar concentrations of FAD and riboflavin inhibited the immune reaction on Western blots and in ELISA, and incubation with FAD-agarose depleted the anti-M7 activity of the serum. N-terminally deleted dimethylglycine dehydrogenase proteins were only immunoprecipitated by anti-M7 sera when the FAD was covalently incorporated. An affinity constant (KD) of 10?8 M was established for the anti-flavoenzyme antibodies by competitive ELISA. Of patients with cardiomyopathy and myocarditis, 36% and 25%, respectively, were anti-flavoenzyme-positive by Western blot and ELISA, but only two of 15 patients with other heart diseases and none of 50 healthy controls.  相似文献   
48.
In 40 patients (pts) (ages 34-83 years) the severity of tricuspid regurgitation (TR) was graded by pulsed Doppler echocardiographic determination of regurgitant jet extension. Mild TR was assessed in seven pts (group I), mode-rate TR in 20 pts (group II), and severe TR in 13 pts (group III). The enddiastolic diameter of the left ventricle as measured by M-mode-echocardiography was 55 +/- 16 mm in group I, 48 +/- 6 mm in group II, and 50 +/- 10 mm in group III. The regurgitant index (RI), i.e., the ratio of left-to-right-ventricular stroke counts (normal range 0.89-1.97) and the time-activity curve over the liver area were measured by equilibrium radionuclide ventriculography (RNV). The RI differed significantly between group I (1.6 +/- 0.5), II (1.0 +/- 0.3), and III (0.8 +/- 0.3) (p less than 0.01). An RI-value below 0.89 as an index of right-ventricular volume overload was found in 14% (group I), 45%, (group II) and 77% (group III). The time-activity curve over the liver area, as graded by count variation in phase with the right atrium from 1 (no count variation) to 4 (typical count variation) showed all grades in groups I and II, but only grade 2 to 4 in group III. The RI resp. the time-activity curve over the liver is a sensitive parameter for the detection of moderate to severe TR. If TR is ascertained, severe regurgitation can be differentiated from mild regurgitation by RNV-derived RI as an index of right-ventricular volume overload.  相似文献   
49.
We evaluated the predictive value of the thyrotropin (TSH) response to thyrotropin-releasing hormone (TRH) in 32 depressed outpatients completing a double-blind placebo-controlled trial of s-adenosyl-l-methionine (SAMe), which failed to show any significant difference between SAMe and placebo. Treatment response was defined as the change in Hamilton Rating Scale for Depression (HRSD-24) score between baseline and the end of the six-week trial. Subjects with TSH response outside the normal range (7-25 uU/ml) had a significantly greater response than patients with a normal response. There was also a significant correlation between absolute deviations from the mean TSH response (16 uU/ml) and changes in HRSD-24 scores.  相似文献   
50.
The purpose of this study was to evaluate and compare the radiographic efficacy and safety of iodixanol (Visipaque; 270 and 320 mg I/ml) and iohexol (Omnipaque; 300 mg I/ml) in myelography. The study was randomized, double-blind and comparative including 398 patients from five European university clinics. The radiographic visualisation was evaluated as poor, good or excellent. Adverse events were recorded by interviewing the patients after the myelography, and each patient was given a questionnaire to be returned after 1 week. In cervical myelography with cervical puncture more films with excellent quality was obtained after iodixanol 320 mgI/ml compared with iohexol 300 mgI/ml (p = 0.009). Also in lumbar myelography iodixanol 320 mgI/ml compared favourably with iohexol 300 mgI/ml (p = 0.006). The most frequent adverse event was headache, which occurred in 5–35 % of patients during the first 24 h and in 19–61 % within the first 7 days, depending on the centre. There was no difference in frequency and severity of the adverse effects between the contrast media. Received 13 March 1997; Revision received 29 December 1997; Accepted 5 January 1997  相似文献   
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