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141.
142.
Urethral reconstruction with graft substances, such as skin and bladder mucosa, has been previously used when primary anastomosis cannot be achieved. However, stricture and meatal prolapse are associated with these grafts. We report the use of buccal mucosa for the reconstruction of urethral defects in 3 patients. One patient with failed operation for hypospadias received tube buccal mucosal graft for urethral replacement. Two patients with urethral necrosis and stricture received onlay buccal mucosal graft. All patients were disease-free during follow-up (range, 12 to 49 months; mean, 36 months). One patient had a pinhole fistula that was successfully managed with simple repair. This technique appears to be useful for urethral reconstruction when a local graft is not available, even in patients with complicated conditions. 相似文献
143.
We describe the enhancement patterns of myoepithelioma in two patients with a soft palate mass. In the first case, helical CT revealed a faintly enhancing mass. Histologically, the tumor was composed of plasmacytoid cells in a background of rich myxoid stroma. Immunostaining for CD34 showed scanty blood vessels. In the second case, helical CT revealed an intensely enhancing mass. Histologically, the mass was a cellular tumor with fibrous stroma. Immunostaining for CD34 also showed frequent blood vessels. 相似文献
144.
145.
Rod photoreceptors of mammalian retinas contain a 33-kDa phosphoprotein, phosducin, which complexes with the beta, gamma-subunits of transducin (T beta gamma). The level of phosducin phosphorylation is modulated by light, suggesting that the phosducin/T beta gamma complex has a pivotal role in light-regulated events that occur in photoreceptors. We have investigated, in developing mouse retinas, the age at which the complex is first detected and the subsequent accumulation of the phosducin/T beta gamma complex during postnatal life. Western blot analysis detected immunoreactivity both for phosducin and T beta in retinal homogenates of 3-day-old mice. Thereafter, the level of immunoreactivity for both proteins increased steadily, to reach adult levels in the next 2 postnatal weeks. Gel filtration analysis of extracts from immature mouse retina showed that phosducin and T beta co-eluted, like the phosducin/T beta gamma complex of adult retina, as a 77-kDa complex, indicating that the phosducin/T beta gamma complex is formed when photoreceptors first synthesize the components of the complex. While the levels of the phosducin/T beta gamma complex increased steadily during the first 2 postnatal weeks, the subunits of transducin complex, T alpha together with additional amounts of T beta gamma, only started to appear around the 7-9th postnatal day, and the level of transducin complex increased sharply at 11-14 days to reach adult levels that are similar to those of phosducin/T beta gamma complex.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
146.
A developmental study of interphotoreceptor retinoid-binding protein (IRBP) in single and double homozygous rd and rds mutant mouse retinae 总被引:1,自引:0,他引:1
T van Veen P Ekstrom B Wiggert L Lee Y Hirose S Sanyal G J Chader 《Experimental eye research》1988,47(2):291-305
Interphotoreceptor retinoid-binding protein (IRBP) was studied using immunochemical and immunocytochemical techniques in retinae of mice with allelic combinations at the rd and rds loci at different stages of development and degeneration. Until postnatal day 7 (P7), IRBP is located intracellularly in developing retinae of the different genotypes. Thereafter, IRBP is present mainly in the interphotoreceptor matrix. As previously noted, cell death is slowest in the heterozygous +/+,rds/+ mutant with loss increasing in order in +/+,rds/rds, rd/rd, rds/rds and rd/rd,+/+ animals. The IRBP content of the total retina also approximates this pattern, with lowest amounts by far in rd/rd, rds/rds and rd/rd,+/+ mutants (after P14). Interestingly though, IRBP loss significantly precedes visual cell loss in the rd/rd,rds/rds retina. In all the mutants, the remaining rod cells in the outer nuclear layer exhibit synthesis of intracellularly located IRBP at late stages of degeneration. In the single homozygous rd/rd,+/+ and the double homozygous rd/rd,rds/rds mutants, IRBP is present intracellularly during the entire degenerative process with somewhat less intracellular IRBP in the rd/rd,rds/rds mutant. Retinae of homozygous +/+,rds/rds and heterozygous +/+,rds/+ animals exhibit a normal distribution pattern of IRBP immunoreactivity until loss of photoreceptor cells becomes pronounced at later stages of the disease. Many of the remaining cells at this time are probably cone elements although they are structurally changed. Double labeling with IRBP and S-antigen demonstrates, in many but not all, the presence of both proteins in the same cell body. Immunocytochemistry clearly demonstrated the presence of IRBP in remaining photoreceptor cells at late stages of the disease. Thus, the biochemically measured loss of IRBP appears to be a complex process neither directly dependent on the loss of photoreceptor outer segments and reduced interphotoreceptor matrix space (e.g. there is a sustained IRBP level in rodless rds mutants) nor simply due to cell death (e.g. in the rd/rd,rds/rds mutant, IRBP loss significantly precedes cell loss). That this IRBP is mainly intracellular, however, may indicate an abnormality in secretion which, combined with other factors, induces a degenerated and less differentiated phenotype. 相似文献
147.
148.
Diurnal variation in peak expiratory flow rate among workers exposed to toluene diisocyanate in the polyurethane foam manufacturing industry. 下载免费PDF全文
The diurnal variation in peak expiratory flow rate (PEFR) was studied in 26 mixers from eight factories making polyurethane foam, who were exposed to toluene diisocyanate (TDI), and 26 unexposed controls matched for age, race, and smoking. They were all men. The mean diurnal variation in PEFR of the mixers was 6.2%, which was significantly higher than the 4.3% for controls. Six mixers had a diurnal variation of greater than 15% on at least one day compared with none among the controls. There was, however, no overt cause of occupational asthma. All but one of the 24 environmental samples taken exceeded the short term exposure limit of 0.02 ppm for TDI. This accounted for the high prevalence (50%) of irritative symptoms such as cough and eye irritation. Forced expiratory volume in one second (FEV1) and FEV1/forced vital capacity (FVC) (%) was negatively correlated with duration of exposure to TDI. Foam workers may still have high exposure to TDI, high prevalence of irritative symptoms, increased diurnal variation in PEFR and evidence of chronic airway obstruction, particularly in those with greater than or equal to 10 years of exposure. 相似文献
149.
The majority, if not the entire life cycle, of the large dsDNA-containing algal virus PBCV-1 occurs in localized regions in the cytoplasm. Thirteen drugs that disrupt the cytoskeleton had no effect on PBCV-1 replication at concentrations which inhibited host growth. Therefore, host cytoskeletal elements do not appear to be important in PBCV-1 morphogenesis. 相似文献
150.
Sun Weidong Hansell Stedman Chen Xiaoli Wei Yu Liu Meizhen Xu Chengbin H. Lee Sweeney 《中华医学杂志(英文版)》1998,(6):495
LigasechainreactionfordiagnosisoffamilialhypertrophiccardiomyopathySunWeidong孙维东,HanselStedman,ChenXiaoli,WeiYu,LiuMeizhen,Xu... 相似文献