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1.
Kaplan  PA; Reiskin  AB; Tu  HK 《Radiology》1987,163(1):217-220
Arthrograms of the temporomandibular joint were obtained in 20 symptomatic joints that had previous reconstructive arthroplasty with disk repositioning because of internal derangements. Preoperative arthrograms were available for comparison in 18 joints. Symptoms resulting in a postoperative arthrogram included pain, limited ability to open the mouth, and clicking of the joints. Postoperative arthrographic findings included limited anterior translation of the condyle (90%), irregularity in outline of the intraarticular contrast agent (60%), a conical configuration of the posterior recess (25%), decreased size of the joint (28%), anterior displacement of the meniscus (25%), and perforated meniscus (15%). Many of these findings may have resulted from fibrosis and scarring, which may be a response to intraarticular bleeding. The mechanism by which the fibrosis causes the postsurgical arthrographic features is discussed.  相似文献   
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Deregulation of telomerase, a ribonucleoprotein polymerase that compensates progressive loss of telomeric (TTAGGG)n repeats during DNA replication, has been suggested to facilitate tumorigenesis and cellular immortality by providing unlimited proliferation capacity for cancer cells. We investigated the relationship between tumor proliferation activity and in situ expression of the telomerase RNA component in 46 human grade I to IV astrocytomas. Heterogeneously distributed telomerase RNA expression was detected from all of the tumor samples as well as from normal human brain tissue. However, expression of telomerase RNA was significantly increased in highly malignant tumors (P = 0.024) and in tumors that showed increased proliferation activity determined by MIB-1 immunohistochemistry (P = 0.014). Interestingly, increased telomerase RNA levels were observed in a subgroup of grade II astrocytomas that showed significant increase in proliferation activity (P = 0.047), indicating that the telomerase RNA component is up-regulated already in early states of astrocytoma malignancy. Telomeric repeats amplification assays revealed telomerase activity in 4 of 6 glioblastomas and in 1 rapidly proliferating grade II astrocytoma. These results suggest that increased tumor proliferation activity triggers telomerase activation via mechanisms that involve increased production of the telomerase RNA component.  相似文献   
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AIMS: Neuroblastic tumours (NTs) have been shown to respond to imatinib treatment in vivo and in vitro, possibly via inactivating the c-kit receptor. The purpose of this study was to identify gastrointestinal stromal tumour (GIST)-type c-kit gene associated mutations in exons 9, 11, 13, and 17 in NTs to recognise a subset of tumours that would probably respond to imatinib treatment. METHODS: Expression of the c-kit protein was detected immunohistochemically in a total of 37 archival paraffin wax embedded NTs using polyclonal rabbit antihuman c-kit antibody. After immunohistochemistry, c-kit gene associated chromosomal mutations in all cases of NT were detected with denaturing high performance liquid chromatography (HPLC). RESULTS: Denaturing HLPC analysis did not reveal GIST-type mutations in four immunohistochemically detected c-kit positive or in 33 c-kit negative NTs. CONCLUSIONS: c-kit receptor expression and GIST-type c-kit gene mutations are rare events in NTs. Oncogenic activation of c-kit in NTs presumably differs from that of GISTs, which may influence their responsiveness to imatinib treatment. Whether c-kit has an essential role in the pathogenesis of NTs remains to be investigated.  相似文献   
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BACKGROUND: Quality of life (QOL) assessment has emerged to measure and quantify the balance between treatment benefit and toxicity, and has a value in predicting response and overall survival in cancer patients. METHODS: From July 1995 to February 1997, 38 symptomatic patients with advanced non-small cell lung cancer (NSCLC) were treated with MIP chemotherapy (mitomycin 6 mg/m2, ifosfamide 3000 mg/m2 and cisplatin 50 mg/m2 on day 1 every 3 weeks). Patients were assessed for QOL including physical well-being, general symptoms and lung cancer-specific symptoms, as well as objective response. RESULTS: The overall response rate was 38.9% (14/36, all were partial response) and the median duration of response was 3.5 months [95% confidence interval (CI) 2.0-4.0]. The median duration of overall survival was 7 months (95% CI 5.9-8.5). The overall improvement of QOL was 58.3% with 21 patients feeling better on treatment. The toxicity of chemotherapy was mild, mainly nausea/vomiting and minimal alopecia. Using multiple clinical predictors of survival (age, histology, stage, performance status), only change of QOL emerged significantly (P = 0.0007). CONCLUSIONS: MIP had an endurable response and low toxicity profile, and provided good QOL. Integral QOL data in our study provided the strong prediction of survival in advanced NSCLC. Further experienced QOL study will provide greatly enhanced outcome data in clinical trials.   相似文献   
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IntroductionThis study aimed to examine the dynamic recovery of established multispecies biofilms of oral bacteria after an initial treatment by D-enantiomeric peptide DJK-5, L-enantiomeric peptide 1018, or chlorhexidine digluconate (CHX).MethodsOral biofilms from 2 donors were grown on collagen-coated hydroxyapatite disks for 3 weeks and exposed to DJK-5, 1018, and 2% CHX for 3 minutes. Immediately after treatment and 1, 2, 3, 5, 7, 8, and 12 weeks after exposure, the biofilm volume and the volume ratio of dead and live bacteria in biofilms were assessed by confocal laser scanning microscopy using a live/dead viability stain. Results were examined by 1-way analysis of variance and post hoc multiple comparisons to determine significance at a P < .05 significance level.ResultsDJK-5 killed almost 80% of biofilms in 3 minutes and maintained this high level of dead bacteria for 1 week. The proportion of viable bacteria in DJK-5–treated biofilms returned to the pretreatment level after 12 weeks. The biovolume of DJK-5–treated biofilm remained significantly lower than that of biofilms after CHX and no treatment throughout the 12-week follow-up period (P < .001). The proportion of dead bacteria was higher in biofilms exposed to DJK-5 than with 1018 or CHX for 8 weeks after the exposure (P < .001). The proportion of dead bacteria almost doubled to 46%–52% during the first 7 days after the 3-minute exposure to CHX and peptide 1018. The timeline of biofilm recovery was slow but similar after exposure to CHX and the 2 peptides.Conclusionsecovery time after exposure to DJK-5 was longer than that after exposure to 1018 and CHX. Peptide 1018 showed a delayed, continued antibacterial effect similar to that of 2% CHX against the biofilm microbes.  相似文献   
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The combination of high-dose busulfan (16 mg/kg) and 200 mg/kg cyclophosphamide is gaining increasing significance as a preparative regimen prior to autologous, syngeneic, or allogeneic marrow transplantation. A new regimen of high-dose busulfan in conjunction with a reduced dose of 120 mg/kg cyclophosphamide has recently been described as a preparative regimen prior to allogeneic transplantation. To determine the drug-related nonhematologic toxic effects of this new regimen without confounding factors associated with allogeneic transplantation, we conducted a pilot study using this new regimen in 20 patients with acute myeloid leukemia (AML) in first remission prior to autologous unpurged marrow transplantation. All patients experienced transient non-life-threatening acute drug-related toxicity with skin reactions in 20 (100%), nausea and vomiting in 20 (100%), oral mucositis in 18 (90%), hepatic functional impairment in 17 (85%), hemorrhagic cystitis in three (15%), and generalized seizures in two (10%) of these patients, respectively. Two procedural, fatal complications resulted from infectious causes that were not directly related to the speed of hematopoietic reconstitution or the toxicity of the preparative regimen. The 3-year event-free survival estimate (55% +/- 11%) and probability of leukemic recurrence (38% +/- 11%) attained with this new regimen in recipients of autografts in first remission of AML are promising and challenge comparisons with preparative regimens employing combinations of cytotoxic agents or total body irradiation (TBI).  相似文献   
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