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991.
The possible mechanism of minimization of prosthesis-derived bone growth inhibitors by shielding of the metal and the reduction, if not elimination, of the associated metal dissolution was investigated. Titanium, aluminium and vanadium release rates were determined in vitro for Ti alloy specimens both with and without a calcium phosphate coating. Ti orderly oriented wire mesh (OOWM) porous coatings on Ti-6Al-4V substrates were used as the metal specimens. Half of the specimens were coated with a 75 microns calcium phosphate ceramic (CPC coating). Seven reference (OOWM) and seven coated (OOWM-CPC) specimens were immersed and placed along with seven control solutions for various periods in an incubator maintained at 37 degrees C and 5% CO2 - air atmosphere. Whereas the reference solutions showed a Ti release increasing as a function of time, the solutions that had the CPC-coated specimens contained no measurable amounts of titanium. The Al in solution around the CPC-coated specimens was significantly greater than the concentration around non-coated specimens. The Al, however, did not increase significantly with time, at least up to 4 wk immersion. The ceramic coating had a small beneficial effect on V concentration. In the absence of a significant adverse effect of Ti on local bone tissue formation, we focus on the Al data of our study. The possible adverse effect of this element is well documented. The calcium phosphate coating produced a significant increase of biological fixation, yet at the same time a greater Al release into solution, calling into question the significance of CPC coating in shielding adverse metal passive dissolution to explain enhanced bone growth [corrected]. 相似文献
992.
S H Han W Y Lee J S Kim J K Roh S B Lee H Myung 《Journal of Korean medical science》1989,4(3):139-141
A 47-year-old man had suffered oscillopsia associated with palatal myoclonus for 10 years. High-field magnetic resonance imaging (MRI) revealed a cryptic vascular malformation within the "Guillain-Mollaret triangle" which was thought to be the responsible lesion. 相似文献
993.
慢性乙型肝炎患者肝组织中HBV抗原表达特征及其临床意义 总被引:5,自引:0,他引:5
目的探讨慢性乙型病毒性肝炎肝活检组织中检测乙肝表面抗原(HBsAg)和乙肝核心抗原(HBcAg)表达强度及表达方式的必要性。方法采用EnVision免疫组织化学法检测196例慢性乙型肝炎患者肝穿组织中HBsAg和HBcAg的表达水平,并用荧光定量PCR检测其血清中的HBV DNA的含量。对肝组织进行炎症活动度分级和纤维化分期。结果肝组织中的HBsAg表达强度和表达方式与炎症分级、纤维化分期和血清乙肝病毒载量均无相关性(P>0.05)。HBcAg表达强度与炎症分级无相关性(r=-0.02,P>0.05);与纤维化分期呈负相关(r=-0.28,P<0.01);与血清乙肝病毒载量呈正相关(r=0.53,P<0.01)。HBcAg表达方式与炎症分级为负相关(r=-0.27,P<0.01),其中浆型组炎症活动度分级高于核型组和混合型组(P<0.01),混合型组高于核型组(P<0.01)。HBcAg表达方式与纤维化分期亦呈较弱的负相关(r=-0.23,P<0.01),其中浆型组纤维化分期高于核型组和混合型组(P<0.05)。HBcAg表达方式与血清乙肝病毒载量呈正相关(r=0.22,P<0.01)。结论区分肝组织中的HBsAg表达强度和表达方式无益于了解慢性乙型肝炎患者肝损害的程度,而检测肝组织中的HBcAg则有助于临床抗病毒治疗。 相似文献
994.
Shiga toxin is transported from the endoplasmic reticulum following interaction with the luminal chaperone HEDJ/ERdj3 下载免费PDF全文
Shiga toxin (Stx) follows a complex intracellular pathway in order to kill susceptible cells. After binding to cell surface glycolipids, the toxin is internalized and trafficked in retrograde fashion to the endoplasmic reticulum (ER). From the ER lumen, the toxin must gain access to the cytoplasm, where it enzymatically inactivates the 28S rRNA, inhibiting protein synthesis. The host molecules involved in this pathway and the mechanisms utilized by the toxin to access the cytoplasm from the ER are largely unknown. We found that Stx is capable of energy-dependent transport across the ER lumen, as has recently been demonstrated for the cholera and ricin toxins. Genetic screening for molecules involved in Shiga toxin trafficking yielded a cDNA encoding a prematurely truncated protein. Characterization of this cDNA revealed that it encodes a novel Hsp40 chaperone, designated HEDJ or ERdj3, localized to the ER lumen, where it interacts with BiP, a molecule known to be involved in protein retrotranslocation out of the ER. We demonstrated that within the ER lumen Stx interacts with HEDJ and other chaperones known to be involved in retrotranslocation of proteins across the ER membrane. Moreover, sequential immunoprecipitation revealed that Shiga toxin was present in a complex that included HEDJ and Sec61, the translocon through which proteins are retrotranslocated to the cytoplasm. These findings suggest that HEDJ is a component of the ER quality control system and that Stx utilizes HEDJ and other ER-localized chaperones for transport from the ER lumen to the cytosol. 相似文献
995.
Dennis M Edelstein K Copeland K Frederick JA Francis DJ Hetherington R Blaser SE Kramer LA Drake JM Brandt ME Fletcher JM 《Neuropsychology》2005,19(4):456-465
Inhibition of return (IOR) refers to an increase in time to react to a target in a previously attended location. Children with spina bifida meningomyelocele (SBM) and hydrocephalus have congenital dysmorphology of the midbrain, a brain region associated with the control of covert orienting in general and with IOR in particular. The authors studied exogenously cued covert orienting in 8- to 19-year-old children and adolescents (84 with SBM and 37 age-matched, typically developing controls). The exogenous cue was a luminance change in a peripheral box that was 50% valid for the upcoming target location. Compared with controls, children with SBM showed attenuated IOR in the vertical plane, a deficit that was associated with midbrain dysmorphology in the form of tectal beaking but not with posterior brain volume loss. The data add to the emerging evidence for SBM deficits in attentional orienting to salient information. 相似文献
996.
Lee KW Yun T Song EK Na II Shin H Bang SM Lee JH Lee ST Kim JH Yoon SS Lee JS Park S Kim BK Kim NK 《Journal of Korean medical science》2005,20(4):598-562
Recent clinical trials showed that bortezomib, a novel proteasome inhibitor, had therapeutic activity in multiple myeloma. However, there was no data about the feasibility of bortezomib in Korean patients. We performed a pilot study of bortezomib in patients with relapsed or refractory myeloma (1.3 mg/m2 twice weekly for 2 week in a 3-week cycle). Seven patients were enrolled. The median age of patients was 59 yr. All patients previously received VAD (vincristine, doxorubicin and dexamethasone) and thalidomide chemotherapy. Three patients previously received alkylator-containing chemotherapy and 4 patients, autologous stem cell transplantation. Bortezomib monotherapy resulted in 3 partial remissions (43%), 3 no changes (43%) and 1 progressive disease (14%). One patient who had no response to bortezomib monotherapy experienced partial remission after addition of dexamethasone to bortezomib. The most common serious toxicity was thrombocytopenia (grade 3/4, 10 of 20 cycles (50%)) and grade 3 peripheral neuropathy was developed in 2 of 20 cycles (10%). Drug-related adverse event led to discontinuation of bortezomib in 1 patient. There was no treatment related mortality. Overall, bortezomib seems to be effective and feasible. Conduction of larger clinical studies on Korean patients is necessary to characterize clinical efficacy and safety of bortezomib more precisely. 相似文献
997.
998.
Andrew D Chantry John A Snowden Charles Craddock Karl Peggs Claire Roddie Jenny I O Craig Kim Orchard Keiren E Towlson Rachel M Pearce David I Marks 《Biology of blood and marrow transplantation》2006,12(12):1310-1317
Relapsed acute myeloid leukemia (AML) in adults has a poor prognosis if treated with chemotherapy alone. Case series have previously supported the role of myeloablation and autologous transplantation as a potentially curative treatment. This study aimed to use the large numbers and extended follow-up data in the British Society of Blood and Marrow Transplantation (BSBMT) registry database to establish long-term outcomes and relate these to biological and procedural factors. The BSBMT registry database was used to retrospectively identify 152 adult patients (age, 16-69 years) with AML in second remission treated with autologous transplantation in 1982-2003. Cytogenetic data were available for 68% of the patients; of these, at diagnosis, 42% had good risk features, 57% had standard risk features, and 1% had poor risk features. Conditioning regimens varied; autologous rescue was provided with bone marrow (BM) (71%), peripheral blood stem cells (PBSCs) (18%), or both (11%), which were harvested during first complete remission (CR1) and/or second CR (CR2). Median follow-up was 84 months (range, 2-200 months). At 10 years, actuarial overall survival (OS) was 32%, progression-free survival (PFS) was 28%, and relapse rate (RR) was 57%. The 100-day nonrelapse mortality (NRM) was 7%, rising to 11% at 1 year and to 14% at 10 years. OS was significantly related to M3 subtype (5-year OS, 66%; P = .005), patient age at diagnosis (P = .005) and transplantation (P = .026), and length of CR1, with greatest significance if the patient was dichotomized at CR1 duration of < 8 months or > or = 8 months (P = .0001). There was no difference in OS between regimens containing total body irradiation (TBI) and chemotherapy alone (P = .7). In relation to the nature of autologous graft material, there was improved OS (P = .025) and PFS (P = .009) with the use of cells harvested entirely in CR1 compared with cells harvested in CR2 or in both CR1 and CR2. Engraftment times were significantly shortened with the use of PBSCs alone or in combination with BM compared with BM alone (P = .0001), but there was no significant long-term impact on OS, PFS, RR, or NRM. This study provides long-term follow-up data in one of the largest series of patients with standard-risk and good-risk AML in CR2 treated with autologous transplantation and supports earlier observations that long-term survival is achievable in about 1/3 of patients overall and in about 2/3 of patients with M3 with a relatively low NRM. Outcomes are better in patients with CR1 > or = 8 months by use of grafts obtained entirely in CR1 and use of PBSCs. TBI conditioning did not confer an advantage. Randomized studies against unrelated donor transplantation are warranted. 相似文献
999.
目的:为踝、距下关节病变及损伤的诊断、修复和重建提供矢状断层解剖学基础。方法:用成年男尸右足标本5例,置冰柜冻硬后,每例切制4个踝及后足部矢状断层标本。结果:胫距关节矢状径最长为31.9mm,距骨滑车与胫骨关节软骨厚各为2.5mm与2.4mm,胫距关节间隙为2.6mm,内侧韧带厚为3.1mm;前、后距下关节软骨厚分别为1.5mm、1.2mm与1.7mm、1.4mm,关节间隙为0.8mm与1.4mm,后距下关节矢状径最长为18.9mm,距跟骨间韧带长8.6mm,矢状径为2.6mm。结论:本文结果为临床踝、距下关节疾患的诊治及关节镜技术提供了解剖学资料。 相似文献
1000.
Comparison of full length sequences of hepatitis B virus isolates in hepatocellular carcinoma patients and asymptomatic carriers of Korea 总被引:4,自引:0,他引:4
Relatively few genomic sequences of Korean hepatitis B virus (HBV) isolates are available. Moreover, no comparative study has been made between the full-length genomes of Korean HBV isolates and clinical status. To evaluate mutations in HBV isolates obtained from chronically infected HBV patients in terms of clinical significance, we determined the genomic sequences of HBV isolates obtained from three hepatocellular carcinoma (HCC) patients (He52, He53, and He82) and from three asymptomatic carriers (He74, He100, and He127). A comparison of sequence variations showed that the HBV isolates from the three HCC patients showed higher frequencies of mutation than the isolates from the three asymptomatic carriers. Three characteristic mutation patterns were identified in the HBV isolates from the HCC patients, which distinguished the HBV isolates from the asymptomatic carriers. First, HBV isolates from the three HCC patients both had double mutations in a core promoter (T1762/A1764) and a precore mutation (A1896). Second, although these isolates belonged to genotype C, 11 amino acids deletions in the preS1 region, specific for HBV genotype D, were detected in the isolates of two HCC patients (He52 and He82). Third, mutations (I127T/N, K130M, and V131I) at three codons in the carboxy functional region of X protein were observed in isolates from all three HCC patients. Additionally, phylogenetic analysis based on the entire HBV sequences showed that all six isolates belonged to genotype C2, as do other Korean strains. 相似文献