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1.
D Gröne† R Treudler† EM de Villiers‡ R Husak† CE Orfanos† ChC Zouboulis†§ 《Journal of the European Academy of Dermatology and Venereology》2006,20(2):202-205
Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment. 相似文献
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The receptor tyrosine kinase (RTK) Ret is activated by the formation of a complex consisting of ligands such as glial cell line-derived neurotrophic factor (GDNF) and glycerophosphatidylinositol-anchored coreceptors termed GFRalphas. During activation, Ret translocates into lipid rafts, which is critical for functional responses to GDNF. We found that Ret was rapidly ubiquitinated and degraded in sympathetic neurons when activated with GDNF, but, unlike other RTKs that are trafficked to lysosomes for degradation, Ret was degraded predominantly by the proteasome. After GDNF stimulation, the majority of ubiquitinated Ret was located outside of lipid rafts and Ret was lost predominantly from nonraft membrane domains. Consistent with the predominance of Ret degradation outside of rafts, disruption of lipid rafts in neurons did not alter either the GDNF-dependent ubiquitination or degradation of Ret. GDNF-mediated survival of sympathetic neurons was inhibited by lipid raft depletion, and this inhibitory effect of raft disruption on GDNF-mediated survival was reversed if Ret degradation was blocked via proteasome inhibition. Therefore, lipid rafts sequester Ret away from the degradation machinery located in nonraft membrane domains, such as Cbl family E3 ligases, thereby sustaining Ret signaling. 相似文献
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J Dow M A Petty J M Grisar E R Wagner K D Haegele 《Drug metabolism and disposition》1991,19(6):1040-1045
MDL74270 (6-acetyloxy-3,4-dihydro-N,N,N,2,5,7, 8-heptamethyl-2H-1-benzopyran-2-ethanaminium, 4-methylbenzenesulfonate) is a quaternary amine analogue of alpha-tocopherol with free radical scavenger properties. Rats were injected iv with [14C]MDL74270 (0.91 mg/kg), and whole blood and heart tissue were sampled. Five min after drug, the heart tissue/blood ratio (T/B) of radioactivity was 3.5, whereas at 1 hr it was 20.1 and remained at this value up to at least 6 hr. After iv administration the t 1/2 of radioactivity in blood was 6.3 hr, but po blood levels could not be quantified. The 0- to 96-hr urinary elimination of radioactivity was 39.9 +/- 5.7% of the dose after iv and only 1.2 +/- 0.4% after po administration, conversely, 44.7 +/- 5.2% was excreted in feces after iv and 79.1 +/- 17.4% after po administration. These results confirmed poor oral absorption of the compound. Tissue distribution of [14C]MDL74270 was compared with that of its tertiary amine analogue [14C]MDL74366 in rat heart, skeletal muscle, brain, and whole blood, after iv administration (1 mg/kg). The heart T/B was above 20, 1-6 hr after [14C]MDL74270, whereas it was less than 2 after [14C]MDL74366. Over the 1- to 6-hr time interval, skeletal muscle T/B varied from 1.8 to 5 compared with 1.5 to 0.6 for [14C] MDL74366. Brain T/B was higher after the tertiary amine compound. Results showed marked cardioselectivity of radioactivity after [14C] MDL74270. Differential centrifugation of heart homogenates showed that radioactivity was equally distributed between the major subcellular fractions studied.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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R Rupprecht A Lippold C Auras G Bramkamp C Breitkopf H-J Elsmann EM Habenicht V Jasnoch H Müller-Pannes K-W Schulte L Suter 《Journal of the European Academy of Dermatology and Venereology》2007,21(2):178-185
Background Cosmetic changes are to be expected after radiotherapy for skin tumours. Objectives This study aimed to answer the questions: How frequent are cosmetic changes after soft X‐ray therapy? Do treatment parameters, tumour thickness, localization and size of the irradiated field have a major influence? Were patients irritated by the visual appearance of the irradiated field? Methods In total, 2474 examinations of 1149 irradiated fields were performed. Results Hypopigmentation was found in 64.7% of examinations more than 90 days after therapy, teleangiectases in 43.1%, erythema in 24.8%, and hyperpigmentation in 16.8%. The frequency of hypopigmentation, teleangiectases and hyperpigmentation increased with time from X‐ray exposure; more than 4 years after therapy hypopigmentation was diagnosed in 91.8% and teleangiectases in 82.2% of examinations. Total dose, the time–dose–fractionation factor (TDF), field size and dose per fraction were significantly related to the frequency of cosmetic changes. Incidence rates of cosmetic changes differed by less than 15% if different treatment conditions were compared: thicker vs. thinner tumours, larger vs. smaller fields, higher vs. lower total doses, doses per fraction, and TDF. Frequencies of hypopigmentation, teleangiectases, erythema and hyperpigmentation differed by more than 15% between some localizations on the head. Women reported irritation by the visual appearance of the irradiated field in 12.6% of 1116 interviews, and men in 4.4% of 1284 interviews. Conclusions Cosmetic changes after soft X‐ray therapy are relatively frequent. Treatment parameters, tumour thickness and field size have only a minor influence. Few patients, but more women than men, were irritated by the visual appearance of the irradiated field. 相似文献
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Laparoscopic-assisted percutaneous endoscopic gastrostomy in children and adolescents. 总被引:3,自引:0,他引:3
Sherman C Yu John K Petty Denis D Bensard David A Partrick Jennifer L Bruny Richard J Hendrickson 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(3):302-304
OBJECTIVE: Pediatric gastric access for long-term enteral feeding may be performed via a laparotomy, laparoscopy, or a percutaneous approach. In children and adolescents, laparoscopic-assisted gastrostomy may be difficult due to a thick abdominal wall. Therefore, if the abdominal wall is estimated to be >2 cm on physical examination, or in children in whom a percutaneous endoscopic gastrostomy was unsuccessfully attempted by a gastroenterologist, we routinely perform a laparoscopic-assisted percutaneous endoscopic gastrostomy. METHODS: From January 1998 through February 2003, we retrospectively reviewed 15 cases of a laparoscopic-assisted percutaneous endoscopic gastrostomy. Instruments used to perform this technique are a percutaneous endoscopic gastrostomy kit, an Olympus flexible endoscope, and one 5-mm STEP port placed through an infraumbilical incision for a 5-mm, 30-degree scope. RESULTS: Age range was 2 years to 20 years (mean, 10). Operative time ranged from 20 minutes to 45 minutes. When a concurrent laparoscopic Nissen fundoplication was performed (n = 6), the percutaneous endoscopic gastrostomy was placed after completion of the Nissen fundoplication. No intraoperative complications occurred, and all tubes were successfully placed. Feeds were instituted the following day and advanced to goal. To date, no postoperative complications have occurred, and revision has not been necessary. CONCLUSIONS: Laparoscopic-assisted percutaneous endoscopic gastrostomy in children and adolescents is safe and effective. Utilizing laparoscopy permits evaluation of the peritoneum and lysis of adhesions, if necessary. Moreover, laparoscopy provides excellent exposure for accurate placement of the PEG, while avoiding injury to other organs. 相似文献
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MA Nasar FRCP FRCP EM Lyle BSc MRPharmS 《International journal of clinical practice》1994,48(1):19-21
SUMMARY Serum potassium was measured within 24 hours in 156 patients (48 male, 108 female) with an average age of 81.9 years admitted to the unit with acute illness. Of the 156 patients, 88 (56.4%) were taking diuretics (none was on ACE inhibitors); 20 patients (12.8%) were also on digoxin therapy. In all, 24 patients (16%) had hypokalaemia and 3 (2%) hyperkalaemia. Hypokalaemia was seen in patients associated with acute illness. There was no significant difference between the diuretic and non-diuretic groups. Monitoring of serum potassium is not routinely indicated to detect hypokalaemia in patients on diuretic therapy except in those with severe hepatic or renal impairment or those on digoxin. 相似文献
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