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1.
Simultaneous angiographic late stent thrombosis in two different coronary vessels after withdrawal of the combined anti-platelet therapy 总被引:2,自引:2,他引:0
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Five ileal conduit biopsies, taken after 1-7 years, were examined by light microscopy and scanning electron microscopy. The total height of the lamina mucosa decreased from 700 to 275 microns. The height of the villi diminished from 550 to 50 microns; the depth of the crypts increased from 130 to 244 microns and the villus-crypt index changed from 4.2 to 0.2. Signs of chronic inflammation could be observed. Scanning electron microscopy shows that the number of microvilli per cell was markedly reduced. There was a varied picture of different stages of atrophy. After 3 years microvilli could no longer be observed. In view of the prolonged urinary contamination time, it appears to be imperative to check neobladders with regard to possible carcinoma induction. 相似文献
4.
Iatrogenic damage to the orbital fascial system during strabismus surgery may lead to adherences with resulting problems of motility. To prevent new adherences in revisional surgery, several materials were tried, with varying degrees of success. The authors tested Polyglactin 910, popular as a suture material in strabismus surgery, in the form of a net. The material is hydrolytically soluble. Since the tissue response is finished before dissolution of the implant, it seemed that Polyglactin would be a suitable barrier to the formation of adhesions in Tenon's capsule. The implant was applied in 11 patients, some of whom had already undergone several strabismus operations and had adhesions at the surgical site. In one case the implant was used in a primary procedure. In one patient revisional surgery was needed four weeks after surgery because of overeffect, and this provided an opportunity to investigate the implanted area histologically. 相似文献
5.
Bone morphogenetic proteins (BMPs) are bone growth factors, which regulate bone formation during fetal development and bone repair after injury in postfetal life. Since 1992 BMP-7 has been produced by recombinant technique (rhBMP-7). Numerous animal models and clinical trials have shown that rhBMP-7 can induce de novo bone formation in segmental defects of bones and in cases of nonunion. Since 2001 rhBMP-7 has been approved for treatment of tibial nonunion in Europe. The effect of rhBMP-7 is comparable to the clinical and radiological results achieved with bone autografts. The problem of donor site morbidity (which occurs in up to 20% of all cases) is eliminated by the use of BMP-7. Long-term results and experience in clinical practice are not yet available. 相似文献
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(S)-Emopamil ((2S)-2-isopropyl-5-(methylphenethylamino)-2-phenylvaleronitril e hydrochloride) is a novel compound of the phenylalkylamine group of calcium antagonists. (S)-Emopamil was tested in comparison to verapamil and gallopamil for calcium and serotonin antagonism and for cerebroprotective activity in acute hypoxia/ischemia. In receptor binding studies with (S)-3H-devapamil, (S)-emopamil exhibited distinct affinity to the verapamil binding site of the calcium channel. In rat cerebrocortical membranes, its affinity (Ki = 38 nmol/l) equalled that of verapamil and gallopamil (Ki = 49 and 27 nmol/l, respectively), whereas it was somewhat weaker in guinea pig skeletal muscle membranes. Comparing (S)-emopamil to its (R)-enantiomer, there was no clear stereoselectivity. Additionally, (S)-emopamil showed very high affinity to the cerebral serotonin S2 receptor; its Ki value (4.4 nmol/l) for 3H-ketanserin displacement being substantially lower than that of verapamil and gallopamil (Ki = 177 and 242 nmol/l, respectively). This feature is clearly stereoselective; (S)-emopamil's affinity was distinctly higher than that of the (R)-enantiomer (Ki = 58 nmol/l). The functional significance of (S)-emopamil's receptor affinity was tested in rat aortic strips. (S)-Emopamil's serotonin antagonistic efficacy (EC50 = 4.5 nmol/l) was an order of magnitude higher than that of verapamil and gallopamil. (S)-Emopamil has a less potent calcium antagonistic effect (EC50 = 270 nmol/l) on the aorta than verapamil and gallopamil (EC50 = 35 and 14 nmol/l, respectively). In isolated electrically driven (1 Hz) left atria of guinea pigs, (S)-emopamil inhibited contractile force at a much higher concentration (EC50 = 29 mumol/l) than verapamil and gallopamil (EC50 = 1.1 and 0.19 mumol/l, respectively).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
Prof. Dr. H. Hofmann 《Infection》1995,23(3):133-138
Summary Virus load was tested by means of PCR calibrated with standards and HCV genotypes were determined by the LIPA-technique using sera from 123 HCV patients. Of these 39 were on renal hemodialysis treatment, 19 suffered from hemophilia, 13 were i.v. drug users and the remaining 52 had none of these risk factors (chronic hepatitis group). The most prevalent subtype in Austria was 1b followed by 3a and 1a. However, genotype 1b infections were found relatively less often in hemophilia patients and drug users than in the other groups, indicating that hemophiliacs probably had been infected by an antihemophilic plasma coming from South American or Asian donors. The highest amounts of virus were found in patients infected with genotype 3a. Determination of the patient's virus load and of the infecting subtype of HCV may be helpful in planning interferon alpha therapy.
Genotyp und Höhe der Virämie bei Patienten mit Hepatitis C Virus Infektion
Zusammenfassung In Sera von Hepatitis C Patienten wurde die Höhe der Virämie mittels PCR sowie der Genotyp des infizierenden HCV bestimmt. Bei insgesamt 123 untersuchten Personen handelte es sich um 39 Dialysepatienten, 19 Hämophile, 13 Drogenabhängige sowie 52 weitere Patienten ohne einen dieser Risikofaktoren (chronische Hepatitis-Gruppe). In Österreich fanden wir den Genotyp 1b vorherrschend, gefolgt von 3a und 1a. Allerdings waren Infektionen mit 1b bei Hämophilen und Drogenabhängigen seltener als bei Dialysepatienten und der Patientengruppe mit chronischer Hepatitis. Hämophile wurden möglicherweise mit antihämophilem Plasma infiziert, dessen Spender aus Südamerika bzw. Asien stammten. Die höchsten Virusmengen im Blut fanden wir bei Personen mit Infektionen durch Genotyp 3a. Die Bestimmung der Virämiehöhe, sowie des infizierten Genotyps könnte für die Indikation einer Interferontherapie bei Hepatitis C von entscheidender Bedeutung sein.相似文献
9.
Replacement of cholesterol gallstones by murideoxycholyl taurine gallstones in prairie dogs fed murideoxycholic acid 总被引:1,自引:0,他引:1
B I Cohen N Ayyad E H Mosbach C K McSherry N Matoba A F Hofmann H T Ton-Nu Y Peng C D Schteingart R J Stenger 《Hepatology (Baltimore, Md.)》1991,14(1):158-168
The effect of two hydrophilic bile acids, murideoxycholic acid (3 alpha,6 beta-dihydroxy-5 beta-cholanoic acid) and ursodeoxycholic acid, on cholesterol and bile acid metabolism and hepatic pathology and gallstone composition was studied in the prairie dog. Cholesterol gallstones were induced by feeding a diet containing 1.2% cholesterol for 75 days. The animals were divided into six groups, and gallstone regression was studied as follows: groups 2 and 5, chow plus 0.2% cholesterol; groups 3 and 6, chow plus 0.2% cholesterol plus 0.15% ursodeoxycholic acid; groups 4 and 7, chow plus 0.2% cholesterol plus 0.15% murideoxycholic acid. Animals in groups 2 to 4 were killed after an additional 6 wk; animals in groups 5 to 7 were killed after an additional 12 wk. Gallstone dissolution did not occur in any group. The gallstones in groups 2, 3, 5 and 6 were typical cholesterol aggregates, as determined by polarized light microscopy and Fourier transform infrared spectrometry. The gallstones of the murideoxycholic acid group were large, solitary, dark stones that appeared radiopaque under 22 kVp x-ray examination. Scanning electron microscopy showed that in these stones the cholesterol crystals had been replaced by an amorphous material, both within the stone and on the stone surface. Chemical analysis indicated that at the end of 12 wk the calcium/sodium salt of the taurine conjugate of murideoxycholic acid (murideoxycholyl taurine) comprised 70% of the stones; protein, cholesterol and small amounts of other bile salts were also present. In vitro studies confirmed the insolubility of the sodium and calcium salts of murideoxycholyl taurine. These studies indicate that the hydrophilic bile acids, murideoxycholic acid and ursodeoxycholic acid, did not achieve gallstone dissolution under the conditions used. In the animals fed murideoxycholic acid, an insoluble calcium salt of murideoxycholyl taurine replaced cholesterol as the major constituent of gallbladder stones. This is the first example of an insoluble dihydroxy taurine-conjugated bile acid; administration of the unconjugated bile acid induced precipitation of a kind of gallstone not previously reported. The final result was transformation of cholesterol stones to bile salt stones. 相似文献
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