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991.
Early results of high-flex total knee arthroplasty: comparison study at 1 year after surgery 总被引:2,自引:0,他引:2
We compared clinical [including maximal flexion and range of motion (ROM)] and radiographical outcomes of high-flex versus
conventional implants for total knee arthroplasty (TKA) after 1 year. We also analyzed the factors affecting postoperative
ROM in high-flex implants. The high-flex group (n = 90) had an average maximal flexion of 129.8° (standard deviation (SD), 5.2°) significantly higher than the 124.3° (SD,
9.2°) of the conventional group (n = 90), especially for patients with less than 90° of knee flexion (P < 0.05). There was no significant difference in hospital for special surgery (HSS) score between the two groups. No knee developed
osteolysis, aseptic loosening, or other complications. We found that, for high-flex implants, preoperative ROM had a significant
effect on postoperative ROM. 相似文献
992.
In seven anesthetized dogs, immersion in the upright position to mid-neck level (IM) was compared to pressure breathing (PB) under dry conditions during constant-stimulus diaphragmatic contraction (EPS). The comparison was in terms of EPS-induced changes in alveolar pressure under static condition (Pmus); EPS-induced tidal volume (VT); and the VT/Pmus ratio (C'). It was found that at iso-lung volume (V): (a) Pmus was greater in IM than in PB, the difference increased at higher V; (b) VT was greater in IM than in PB, but the VT difference (deltaVT) did not parallel that in Pmus; VT was maximum at a V equal to approximately 90% of FRC in air (FRCd) and decreased below and above this volume; (c) during both IM and PB, the VT-V relationship reflected a biphasic relationship of C' to V and appeared to be inherent to the upright position. 相似文献
993.
S C Nam K J Kim J W Leem K S Chung J M Chung 《The Journal of comparative neurology》1989,290(3):336-342
We hypothesized that the afferent fibers in the ventral root of the rat are the third branches of dorsal root ganglion cells; these afferent processes in the ventral root are of varying length and end bluntly along the length of the root. In the case of an injury at either the central or the peripheral processes of the dorsal root ganglion cells in the neonatal stage, these fibers sprout at the blunt endings along the length of the ventral root. We cut either the sciatic nerve or the dorsal root on one side in neonatal rats. After the rats were fully grown, the number of both myelinated and unmyelinated fibers was counted in electron photomicrographs at multiple sites along the length of the ventral root. We observed a greatly increased number of unmyelinated fibers in the ventral root after the sciatic nerve had been cut at the neonatal stage. The magnitude of increase was more at the distal than at the proximal portion of the ventral root, suggesting that added fibers originated from the distal side. Neonatal dorsal rhizotomy, however, did not produce the same result. These results are consistent with our hypothesis that peripheral nerve injury at the neonatal stage triggers sprouting of the third branches of the dorsal root ganglion cells which end bluntly along the length of the ventral root in the normal animal. 相似文献
994.
Enzymatic synthesis of phenoxymethylpenicillin from 6-aminopenicillanic acid and phenoxyacetic acid methyl ester was attempted by using partially purified alpha-acylamino-beta-lactam acylhydrolase I (ALAHase I) enzyme from Erwinia aroideae NRRL B-138. The reaction rates were carefully followed by determination of 6-aminopenicillanic acid (6-APA), phenoxymethylpenicillin (PNV), phenoxyacetic acid (POA), phenoxyacetic acid methyl ester (POM), and phenoxyacetylglycine (POG) using high performance liquid chromatography. Among the acyl donors tested, POM gave the highest yield (12.2% based on 6-APA). The overall conversion increased almost linearly with an increase in molar ratio of POM to 6-APA up to 4:1. The effects of organic solvents on the overall yield were also evaluated. Some improvement of PNV yield was observed when ethanol, 2-propanol, and acetone were used. ALAHase I was found to carry out three reactions simultaneously: transfer of acyl group to acyl acceptor to form semisynthetic beta-lactam antibiotic; hydrolysis of acyl donor in amide or ester bond, and hydrolysis of semisynthetic beta-lactam antibiotic which was produced by the enzyme. It was also observed that the hydrolysis reactions of POM and PNV were irreversible in this reaction system. The optimal pH for the three reactions was different. They were: pH 9.0 for POM hydrolysis, 6.8 for the transfer of phenoxyacetyl group to 6-APA, and 6.0 for the PNV hydrolysis. The apparent Km values for POM, 6-APA and PNV were estimated as 33, 25 and 31 mM, respectively. 相似文献
995.
Lee SW Back GM Yi BY Choi EK Ahn SD Shin SS Kim JH Kim SY Lee BJ Nam SY Choi SH Kim SB Park JH Lee KK Park SH Kim JH 《International journal of radiation oncology, biology, physics》2006,65(1):152-160
PURPOSE: To present preliminary results of intensity-modulated radiotherapy (IMRT) with the simultaneous modulated accelerated radiotherapy (SMART) boost technique in patients with nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS: Twenty patients who underwent IMRT for nondisseminated NPC at the Asan Medical Center between September 2001 and December 2003 were prospectively evaluated. Intensity-modulated radiotherapy was delivered with the "step and shoot" SMART technique at prescribed doses of 72 Gy (2.4 Gy/day) to the gross tumor volume, 60 Gy (2 Gy/day) to the clinical target volume and metastatic nodal station, and 46 Gy (2 Gy/day) to the clinically negative neck region. Eighteen patients also received cisplatin once per week. RESULTS: The median follow-up period was 27 months. Nineteen patients completed the treatment without interruption; the remaining patient interrupted treatment for 2 weeks owing to severe pharyngitis and malnutrition. Five patients (25%) had Radiation Therapy Oncology Group Grade 3 mucositis, whereas 9 (45%) had Grade 3 pharyngitis. Seven patients (35%) lost more than 10% of their pretreatment weight, whereas 11 (55%) required intravenous fluids and/or tube feeding. There was no Grade 3 or 4 xerostomia. All patients showed complete response. Two patients had distant metastases and locoregional recurrence, respectively. CONCLUSION: Intensity-modulated radiotherapy with the SMART boost technique allows parotid sparing, as shown clinically and by dosimetry, and might also be more effective biologically. A larger population of patients and a longer follow-up period are needed to evaluate ultimate tumor control and late toxicity. 相似文献
996.
The JAK2 V617F mutation in de novo acute myelogenous leukemias 总被引:5,自引:0,他引:5
Lee JW Kim YG Soung YH Han KJ Kim SY Rhim HS Min WS Nam SW Park WS Lee JY Yoo NJ Lee SH 《Oncogene》2006,25(9):1434-1436
A missense somatic mutation in JAK2 gene (JAK2 V617F) has recently been reported in chronic myeloproliferative disorders, including polycythemia vera, essential thrombocythemia and myelofibrosis with myeloid metaplasia, strongly suggesting its role in the pathogenesis of myeloid disorders. As activation of JAK2 signaling is occurred in other malignancies as well, we have analysed 558 tissues from common human cancers, including colon, breast and lung carcinomas, and 143 acute adulthood leukemias by polymerase chain reaction -- single strand conformation polymorphism analysis. We found three JAK2 mutations in the 113 acute myelogenous leukemias (AMLs) (2.7%), but none in other cancers. The mutations consisted of two V617F mutations and one K607N mutation. None of the AML patients with the JAK2 V617F mutation had a history of previous hematologic disorders. This is the first report on the JAK2 gene mutation in AML, and the data indicated that the JAK2 gene mutation may not only contribute to the development of chronic myeloid disorders, but also to some AMLs. 相似文献
997.
Lee JW Soung YH Kim HJ Park WS Nam SW Kim SH Lee JY Yoo NJ Lee SH 《European journal of cancer (Oxford, England : 1990)》2006,42(14):2369-2373
hCDC4, a ubiquitin ligase, plays a role in the control of cell cycle and chromosome stability. The hCDC4 gene is considered a tumour suppressor gene and is mutated in several human neoplasias, including colorectal and endometrial tumours. Data on the hCDC4 mutation in gastric cancer is, however, lacking. This study explored the possibility that hCDC4 mutation is involved in the development of gastric cancer. The hCDC4 gene in 162 gastric adenocarcinoma tissues was analysed for somatic mutations using a polymerase chain reaction-single strand conformation polymorphism assay. Overall, six hCDC4 mutations were found (3.7%), comprising four missense, one frameshift deletion and one nonsense mutation(s). It is notable that the hCDC4 mutations were found in early as well as in advanced gastric carcinomas. These data indicate that hCDC4 mutation occasionally occurs in gastric carcinomas and suggest that it might play a role in the development of some gastric carcinomas. 相似文献
998.
Combination treatment with temozolomide and thalidomide inhibits tumor growth and angiogenesis in an orthotopic glioma model 总被引:3,自引:0,他引:3
Son MJ Kim JS Kim MH Song HS Kim JT Kim H Shin T Jeon HJ Lee DS Park SY Kim YJ Kim JH Nam DH 《International journal of oncology》2006,28(1):53-59
The chemotherapeutic agent temozolomide (TMZ) and the anti-angiogenic agent thalidomide (THD) have both demonstrated anti-tumor activity in patients with recurrent malignant glioma. Combination treatment with TMZ and THD in patients with glioblastoma multiforme (GBM) appears to be more effective than treatment with either drug alone. To investigate the mechanism of this anti-tumor effect, we examined the combined effects of TMZ and THD in a rat glioma xenograft model. We found that combination treatment markedly inhibited the growth of tumors that were orthotopically implanted into rat brains. Using proliferating cell nuclear antigen (PCNA) staining, we observed a significant decrease in cell proliferation in these tumors. CD31 staining of the microvasculature revealed a significant decrease in angiogenesis. We also found increased apoptosis in treated tumors by terminal deoxynucleotidyl-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay. We further demonstrated that the expression of angiogenic factors, such as vascular endothelial cell growth factor (VEGF) and basic fibroblastic growth factor (bFGF), were inhibited by THD. THD also decreased the number of ED1-positive, activated macrophages or microglial cells, which produce pro-angiogenic molecules around the glioma. Taken together, these results suggest that combination treatment with TMZ and THD inhibits tumor growth via the induction of apoptosis and the inhibition of angiogenesis in a rat model and may be a promising therapy for malignant gliomas. 相似文献
999.
Kim JT Kim JS Ko KW Kong DS Kang CM Kim MH Son MJ Song HS Shin HJ Lee DS Eoh W Nam DH 《Oncology reports》2006,16(1):33-39
Glioblastoma is a highly angiogenic tumor with a dismal prognosis. Temozolomide (TMZ), a methylating agent is one of the most effective chemotherapeutic agents against glioblastoma. To overcome the problem that most of these tumors become resistant to chemotherapeutic regimens within a year, we investigated the antitumor efficacy of metronomic administration of low-dose TMZ in in vitro cell proliferation/cytotoxicity assay and in vivo rat and nude mouse orthotopic glioma model. By in vitro assay, we elucidated that C6/LacZ rat glioma cells were more resistant to metronomic treatment of TMZ than U-87MG human glioblastoma cells and bEnd.3 mouse brain endothelial cells. Compared with the conventional chemotherapeutic regimen of TMZ, we found that frequent administration of TMZ at a low dose (metronomic treatment) markedly inhibited angiogenesis as well as tumor growth in a TMZ-resistant C6/LacZ rat glioma model. In addition, metronomic treatment of TMZ significantly augmented apoptosis of tumor cells in this model. For the TMZ-sensitive U-87MG cells, even with a very low dose of TMZ, which is not effective to reduce tumor mass, the metronomic treatment of TMZ reduced the microvessel density, i.e. angiogenesis, in a nude mouse orthotopic model. In conclusion, for both models, the metronomic treatment of TMZ decreased angiogenesis. Especially, in TMZ-resistant glioma cells, this regimen increased apoptosis of tumor cells and decreased tumor growth. The metronomic treatment of TMZ in orthotopic glioma models demonstrated a successful antiangiogenic effect which can overcome the chemoresistance in conventional TMZ chemotherapy. 相似文献
1000.
Nguyen NP Moltz CC Frank C Vos P Smith HJ Karlsson U Nguyen LM Rose S Dutta S Sallah S 《Oral oncology》2006,42(4):374-380
We would like to assess the evolution of chronic dysphagia (1 year or more) following treatment for head and neck cancer. Modified barium swallow (MBS) examinations were performed in cancer-free patients who complained of dysphagia following treatment for head and neck cancer. The severity of the dysphagia was graded on a scale of 1-7. Each patient had at least 2 MBS. Severity of dysphagia was compared between the first and last MBS study to determine whether the swallowing dysfunction had returned to normal. Patients with complaint of dysphagia and normal MBS also underwent a regular barium swallow to assess the structural integrity of the pharynx and esophagus. Between 1996 and 2001, 25 patients with dysphagia underwent repeat MBS following treatment. Swallowing dysfunction did not return to normal in the majority of the patients. At a median time of 26 months following treatment (range 15-82 months), only two patient (8%) had normalization of the swallowing. The severity of dysphagia decreased in eight patients (32%), remained unchanged in 12 patients (48%), and worsened in five patients (20%). Eight patients (32%) still had aspiration problems at 12-83 months following treatment. Six patients (24%) required dilation because of pharyngeal stenosis. Three patients who required dilation had improvement of the dysphagia severity. Chronic dysphagia is a relentless process possibly due to excessive scarring. Patients with chronic dysphagia are at risk of malnutrition, and aspiration. Management of chronic dysphagia requires a team approach with nutritional support, psychological counseling, dilation, and tube feedings when indicated. 相似文献