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1.
Abstract The aim of the present clinical trial was to test tolerability during 2 treatments with EMDOGAIN® in a large number of patients. An open, controlled study design in 10 Swedish specialist clinics was chosen, with a test group of 107 patients treated with EMDOGAIN® in connection with periodontal surgery at 2 surgical test sites per patient. The procedures were performed 2 to 6 weeks apart on one-rooted teeth with at least 4 mm deep intraosseous lesions. A control group of 33 patients underwent flap surgery without EMDOGAIN® at I comparable site. In total 214 test and 33 control surgeries were performed. Serum samples were obtained from test patients for analysis of total and specific antibody levels. 10 of the patients had samples taken before and after the first surgery. 56 other samples were taken after one treatment with EMDOGAIN®, and 63 after 2 treatments. None of the samples, not even from allergy-prone patients after 2 treatments, indicated deviations from established baseline ranges. This indicates that the immunogenic potential of EMDOGAIN® is extremely low when applied in conjunction with periodontal surgery. Comparison between the test and control groups demonstrated the same type and frequency of post-surgical experiences, i.e., reactions caused by the surgical procedure itself. Clinical probing and radiographic evaluation was performed at baseline and 8 months postsurgery. About half of the patients (44 test and 21 control) were also evaluated after 3 years. There was a significant difference between the test and control results at 8 months post surgery. and this difference had increased further at the 3 year follow-up. The 2.5–3 mm increase in attachment and bone level after treatment with EMDOGAIN® was of the same magnitude as seen in the studies with split-mouth design aiming for lest of effectiveness of EMDOGAIN®.  相似文献   
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Protein composition and mechanical function of intermediate filaments were examined in arteries of different sizes using desmin deficient mice (Des−/−) and their wild-type controls (Des+/+). Using SDS-PAGE gels and Western blots we found a gradient in desmin expression in the arterial tree; the desmin content increased from the elastic artery aorta, via the muscular mesenteric artery to the resistance-sized mesenteric microarteries ∼150 μm in diameter in Des+/+ mice. Mechanical experiments were performed on the aorta, the mesenteric artery and resistance-sized arteries using wire myographs. For aorta and mesenteric artery, no differences in passive or active circumference- stress relations were found between Des−/− and Des+/+ mice. In microarteries, both passive and active stress were lower in the Des−/− group. In conclusion, large elastic and muscular arteries contain a relatively low amount of desmin, and the desmin intermediate filaments do not seem to play a major role in the mechanical properties of these larger arterial vessels. In the microarteries, where expression of desmin is high, desmin plays a role in supporting both passive and active tension.  相似文献   
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Sera from 79 patients with acute self-limiting hepatitis, 17 patients with acute hepatitis B evolving into chronic HBsAg carriership, and 43 chronic HBsAg carriers without a history of acute hepatitis were analyzed for presence of hepatitis B virus (HBV)-DNA by a molecular hybridization technique. In acute self-limiting hepatitis, HBV-DNA was cleared within a few weeks after the onset of clinical symptoms. The longest period of DNA positivity observed in this group was 42 days. In 29 of 52 patients HBV-DNA was cleared before HBeAg disappeared. Among 17 patients who became chronic HBsAg carriers, HBV-DNA was present for more than 6 months in all but one. Most of the HBsAg carriers eventually cleared HBV-DNA. The DNA clearance frequently preceeded the conversion of HBeAg to anti-HBe. Thus, in many patients there was a transitional period with HBeAg but without HBV-DNA. HBV-DNA was found to be a better index of impending chronicity than HBeAg since persistence of HBeAg for more than 42 days was noted in 10% of the patients who nevertheless cleared HBsAg within 6 months. By that time all those patients had turned negative for HBV-DNA. On the other hand, in 16 of the 17 patients who became chronic carriers of HBsAg, HBV-DNA as well as HBeAg persisted for more than 6 months. The present results also suggest that infectivity in acute hepatitis B is a feature mainly of the presymptomatic and early symptomatic period.  相似文献   
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A prevalence of hepatitis C virus (HCV) antibodies of 12% was found in 276 patients from 11 dialysis units. Between zero and 22% of the patients in the different units were anti-HCV positive. The epidemiology of HCV was studied in two units during a 2 year period by antibody assays and the polymerase chain reaction and correlated with clinical manifestations. Two types of epidemiologic patterns were found that may explain the wide difference of HCV prevalence described in different dialysis units. In one unit there was no evidence of spread within the unit, and the prevalence of HCV was dependent on the status of the patients entering for treatment. In the other unit, a clustering of infected patients could be seen in which 13 of 36 were infected during a 3 year period. Some patients who had not received blood transfusions were among the infected. Hepatitis C infection was the most common explanation for repeated abnormal transferase levels. Most of the HCV-infected patients reacted both for anti-HCV and HCV RNA. HCV RNA was in general detected earlier than anti-HCV seroconversion. Among 20 HCV RNApositive serum samples that were anti-HCV ELISA-positive 18 had indeterminate and two negative reactions by immunoblot (RIBA 2). Thus the RIBA 2 test should be used with caution as a confirmatory antibody test in this group of patients. © 1993 Wiley-Liss, Inc.  相似文献   
7.
An 11.8-year median follow-up evaluation of 42 "ideal" patients who had chemonucleolysis was obtained by examination, questionnaire, and roentgenograms. The excellent and good rating of this group was 81%, as compared to the total of 135 patients previously evaluated at 42 months and showing 85.2%. No complications were noted. Disc space rewidening, after initial narrowing, was observed in eight patients and 26% of all discs injected. While all who showed rewidening had excellent results, widening was not necessary to achieve an excellent rating. Marked narrowing and sclerosis of intervertebral margins were seen in many excellent and good clinical results. Chemonucleolysis represents a viable option as definitive treatment for a herniated nucleus pulposus in carefully selected patients.  相似文献   
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Hmi1p is a helicase in the yeast Saccharomyces cerevisiae required for maintenance of the wild-type mitochondrial genome. Disruption of the HMI1 ORF generates and 0 cells. Here we demonstrate that, in yeast strains, Hmi1p stimulates the synthesis of long concatemeric mitochondrial DNA molecules associated with a reduction in the number of nucleoids used for mitochondrial DNA packaging. Surprisingly, the ATPase negative mutants of Hmi1p can also stimulate the synthesis of long concatemeric mitochondrial DNA molecules and support the maintenance of the wild-type mitochondrial genome, albeit with reduced efficiency. We show that, in the mutant hmi1–5 background, the wild-type mitochondrial DNA is fragmented; and we propose that, in hmi1 yeast cells, the loss of the wild-type mitochondrial genome is caused by this fragmentation of the mitochondrial DNA.  相似文献   
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Viral markers of chronic hepatitis were tested for in 95 frozen serum samples from 299 patients from Malm?, Sweden, with hepatocellular carcinoma (HCC), diagnosed between 1977 and 1994. Hepatitis B analysis included anti-HBc, HBsAg and, if anti-HBc positive, HBV DNA. Hepatitis C infection analysis included anti-HCV screening, RIBA, HCV RNA and HCV genotyping. HCV genotyping was also carried out in 9 HCV-viraemic HCC-patients from Gothenburg. HCV genotype distribution in HCC cases was compared with Swedish HCV-infected blood donors. Among the 95 patients from Malm?, 28 (29%) had anti-HBc, but only 5 (5%) were chronic HBV carriers, compared with 16 (17%) with chronic hepatitis C (p = 0.021). HCV-related HCC was more common among immigrants (8/16 vs. 8/79; p < 0.001). Genotyping of 25 HCV-infected cases showed genotype 1a in 6 (24%), genotype 1b in 13 (52%), genotype 2b in 4 (16%), and genotype 3a in 2 (8.0%) patients. Genotype 1b was more common among HCC patients than among blood donors (p < 0.001), but 8 of 13 genotype 1b-infected patients were from countries where genotype 1b is predominant. Among native Swedes there was no difference between the HCV genotypes infecting blood donors and those found in HCC patients.  相似文献   
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