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21.
Determination of the occlusal vertical dimension (OVD) is an integral part of complete dentures fabrication. Due to the lack of teeth, the clinician faces the challenge of how to accurately establish the OVD of the new denture. Therefore, the purpose of this review article was to present, discuss and critique the available methods used in determining the OVD for complete dentures patients. This review identified two main streams to determine the OVD: (i) pre‐extraction methods and (ii) post‐extraction methods. For the pre‐extraction methods, the OVD of the natural dentition is transferred to the new dentures mainly by intra‐oral measurements, profile tracing and cephalometric analysis. The post‐extraction methods rely on mandibular rest position, facial aesthetic appearance, swallowing pattern, craniofacial landmarks measurements, cephalometric analysis, phonetics and existing dentures. In general, all the available techniques have merits and are helpful for routine clinical use. However, they are empirical in nature, controversial and lack the scientific support. Further, there is no single accurate method for OVD determination. To overcome the limitations of the techniques, the clinician will benefit from applying combination of techniques to approximate the OVD.  相似文献   
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23.
Objectives To assess the efficacy and safety of the MEK1/2 inhibitor AZD6244 (ARRY-142886) in patients with metastatic colorectal cancer who had failed one or two previous chemotherapeutic regimens that included oxaliplatin and/or irinotecan. Methods This was a Phase II, multicentre, open-label, randomised, two-arm, parallel-group study comparing AZD6244 with capecitabine monotherapy. Patients received either 100 mg twice daily oral AZD6244 free-base suspension every day or 1,250 mg/m2 twice daily oral capecitabine, for 2 weeks, followed by a 1-week rest period, in 3-weekly cycles. The primary endpoint was the number of patients experiencing disease progression events. Results Sixty-nine patients were randomised in the study (34 and 35 patients in the AZD6244 and capecitabine groups, respectively). Disease progression events were experienced by 28 patients (∼80%) in both the AZD6244 and capecitabine treatment groups. Median progression-free survival was 81 days and 88 days in the AZD6244 and capecitabine groups, respectively. Ten patients in the AZD6244 treatment arm had a best response of stable disease. For capecitabine, best response was a partial response in one patient, with stable disease in a further 15 patients. The most frequently observed adverse events reported with AZD6244 were acneiform dermatitis, diarrhoea, asthenia and peripheral oedema, compared with hand-foot syndrome, diarrhoea, nausea and abdominal pain with capecitabine. Conclusions AZD6244 showed similar efficacy to capecitabine in terms of the number of patients with a disease progression event and of progression-free survival. AZD6244 is currently undergoing evaluation in Phase II trials in combination with other chemotherapeutic agents.  相似文献   
24.
The NY-ESO-1 gene product is expressed by a range of human tumors and is recognized by antibodies from sera of cancer patients with NY-ESO-1-expressing tumors. The NY-ESO-1 gene also encodes several MHC class I- and MHC class II-restricted tumor epitopes recognized by T lymphocytes. In particular, we previously reported that the NY-ESO-1 119-143 peptide contains at least two HLA-DRB1*0401-presented epitopes that are recognized by melanoma-reactive CD4+ T cells. Here we report that the NY-ESO-1 119-143 peptide can be presented in the context of multiple HLA-DR alleles to stimulate tumor-reactive CD4+ T cells. The NY-ESO-1 119-143 peptide is able to bind to several DR molecules. The NY-ESO-1 119-143 peptide is also capable of inducing specific CD4+ T cells in vitro from peripheral blood lymphocytes of normal donors and patients with melanoma who express these HLA-DR alleles. These CD4+ T cells recognize NY-ESO-1(+), HLA-matched or autologous melanoma cell lines, as well as autologous antigen-presenting cells fed with the NY-ESO-1 protein. We also demonstrate that the NY-ESO-1 119-143 peptide stimulates in vitro both Th1-type and Th2-type CD4+ T-cell responses from peripheral blood lymphocytes of normal donors and melanoma patients. Taken together, these data suggest a key role of the NY-ESO-1 119-143 peptide sequence in the induction of cellular and humoral responses against NY-ESO-1-expressing tumors. They support the relevance of cancer vaccine trials with the NY-ESO-1 119-143 peptide in the large number of cancer patients with NY-ESO-1-expressing tumors.  相似文献   
25.
Repeat hepatectomy for colorectal liver metastases   总被引:1,自引:0,他引:1  
This study includes 16 patients (9 men, 7 women; mean age 64 years) who underwent a total of 19 repeat hepatectomies for metastasis after colon (n=7) or rectal (n=9) carcinoma. All patients were reoperated for recurrent liver metastasis after the first resection (mean, 21 months; range, 7-40 months), and three had a third hepatectomy 13, 24, or 65 months after the second. Perioperative mortality was 0% and morbidity was 37%. The 3- and 5-year survival rates after the second resection were 56.8% and 28.4%, respectively, with a median survival of 42.3 months. Seven patients died (mean survival, 25.7 months; range, 9-58 months) before the end of the study. Six patients were alive with one or more recurrences, and three (24, 51, and 173 months of follow-up) were alive without known recurrence. Survival rates for repeat resections of colorectal liver metastases in selected patients were comparable with those obtained after resection of a first liver metastasis.  相似文献   
26.
Family Reoviridae is known, by definition, to contain dsRNA viruses with 10-12 genome segments. We report here the characterization of the first member of this family with a nine-segmented genome. This virus was isolated from Aedes pseudoscutellaris mosquito cells and designated aedes pseudoscutellaris reovirus (APRV). Virions are single-shelled with turrets but are non-occluded by contrast to cypoviruses. APRV replicates in various mosquito cell lines, but not in mice or mammalian cells. Complete sequence analysis showed that APRV is phylogenetically related to cypoviruses, fijiviruses and oryzaviruses. The maximum amino acid identities with cypoviruses, oryzaviruses or fijiviruses in the polymerase, are compatible with values observed between these genera and lower than values within a given genus. This suggests that APRV should be classified within a new genus that we designated Dinovernavirus (sigla from D: Double-stranded, i: insect, nove: nine from the latin "novem", rna: RNA, virus) in family Reoviridae.  相似文献   
27.
Porcine foetal neurons for xenotransplantation in Parkinson's disease (PD) is an alternative source to human fetuses. One of the obstacles facing brain xenotransplantation is the existence of an immune response, which prevents long-term graft survival. Experimental results concerning the survival time of porcine foetal neurons implanted into the brain of immunocompetent rats have been quite different from one study to another, suggesting an effect on graft survival of uncontrolled experimental parameters. To identify such parameters, we have first analyzed the survival of porcine foetal nigral neurons at 5 and 10 weeks after implantation into the striatum of immunocompetent rats having different types of brain lesion affecting cells (quinolinic acid) or projections to the striatum (MPP+, 6-OHDA). In a second experiment, graft survival was analyzed in two strains of recipient rats (female Sprague-Dawley and male Lewis rats) in conditions of ipsilateral dopaminergic denervation using 6-OHDA. The characteristics of surviving grafts were assessed by measuring the graft volume, the number of TH+ neurons, the size of TH+ neurons soma, and CD5+ cell infiltration. Long-term survival (> or = 10 weeks) of porcine neurons could be observed in all experimental models. However, there was no significant difference in graft survival rates and characteristics of the surviving grafts between the lesioned groups, or between Sprague-Dawley and Lewis rats. Altogether, results were highly variable within groups of grafts exposed to similar experimental procedures at both 5 and 10 weeks post-grafting. We conclude that the distinct neurotoxins and host rat strains used in our experimental design are not major factors influencing the rejection time-course of primary neural xenografts.  相似文献   
28.
Dengue is the most common and widespread arthropod borne arboviral infection in the world today. It is estimated that there are at least 100 million cases of dengue fever (DF) annually and 500,000 cases of dengue hemorrhagic fever (DHF) which require hospitalization. In Malaysia, it has become a major public health problem. Malaysia recorded 19,544 dengue cases in 1997, the highest recorded since the disease was made notifiable in the country. Of 19,544 cases, 806 were DHF with 50 deaths. The objectives of this analysis were to describe the incidence of dengue fever and dengue hemorrhagic fever in Kota Bharu, Kelantan, Malaysia for the years 1998-2003 and to explore the characteristics of dengue fever and dengue hemorrhagic fever in Kota Bharu, Kelantan, Malaysia for years 1998-2003. A total of 4,716 dengue cases were notified involving 4,476 (94.9%) DF and 240 (5.1%) DHF cases, which increased though the years. The highest incidence was in January (701 or 14.9%), while the lowest was in May (188 or 4.0%). Forty percent of cases (n=1,890) were in the 15-29 year old group. The Majority were Malays (4,062 or 86.1%) and 2,602 or 55.2% were male. A total of 4,477 cases (95%) were local cases and 4,289 or 91% came from the urban area. For priority areas, 3,772 (80%) were from priority 1. More than half the cases had positive serology results. All symptoms occurred in more than 96% of cases and fever was the commonest (99.7%). The mean values for age, temperature, systolic and diastolic blood pressure (BP) were 27.8 +/- 15.4 years, 37.9 +/- 0.90 degrees C, 115 +/- 15.2 mmHg and 73 +/- 11.1 mmHg, respectively. The mean value for the time interval between the onset of symptoms and diagnosis, onset of symptoms and notification and time of diagnosis to notification were 5.1 +/- 2.3, 5.9 +/- 2.5 and 0.8 +/- 1.1 days, respectively. There were associations between the types of dengue and classification, area and priority area. Among the symptoms, the association was only seen in joint pain. The mean significant differences between DF and DHF were found in age and systolic blood pressure. The incidence of dengue in Kota Bharu is comparable to that in Malaysia. The increase in the number of cases needs to be addressed promptly with effective surveillance, prevention and control programs.  相似文献   
29.
The aim of the study was to investigate the safety and efficacy of a salvage therapy initiated after interrupting treatment in patients with virological failure and more than 200 CD4(+) T lymphocyte count. In this prospective study, 77 patients who received failing regimens had stopped completely all medication for 3 months before starting an optimised regimen consisting of 3-5 drugs. Patients were tested for HIV resistance before and after treatment interruption. Discontinuation of therapy for 3 months was associated with a median increase in HIV RNA of 1.1 log(10), a median decrease in CD4(+) T cell count of 136 x 10(6)/L and five clinical events related to HIV, but no AIDS-defining event. Eighty-seven percent of patients showed a shift from a drug resistant genotype to a wild-type genotype based on the major resistance mutations. Forty-seven percent of patients with a genotype shift reached fewer than 200 HIV RNA copies/ml of plasma 6 and 12 months after treatment resumption whereas none of those without a genotype shift did so (P = 0.03). However, the genotypic shift was not associated with a sustained virological response by multivariate analysis. The use of a new therapeutic class of compound in the salvage regimen was the only predictor of the sustained virological response. Salvage therapy with 3-5 drugs after interrupting treatment for 3 months can be a safe and effective strategy provided the HIV disease is not too advanced. Randomised trials in this population are needed to assess the clinical benefit of this strategy.  相似文献   
30.
The clinical course and sequel of the life-threatening gastrointestinal (GI) bleeding during the treatment of strongyloides helmintic hyperinfection induced by immunosuppression in a patient with multiple myeloma is presented. A 55-year old male patient was diagnosed with strongyloides infection with stool analysis and intestinal biopsy shortly after his combined chemotherapy for myeloma. He was commenced on albendazole anthelmintic therapy. However, after initiation of the treatment he suffered life-threatening GI bleeding. Repeated endoscopies, including intraoperative enteroscopy, concluded to diffuse multifocal intestinal bleeding. The patient required huge amounts of red blood cells and plasma transfusions and correction of haemostasis with recombinant activated factor VII. Abdominal aorto-angiography showed numerous microaneurysms ("berry aneurysms") in the superior and inferior mesenteric arteries' territories. While the biopsy taken prior to the treatment with albendazole did not show evidence of vasculitis, the biopsy taken after initiation of therapy revealed leukoclastic aggregations around the vessels which was also consistent with vasculitis. These findings suggest that--in addition to direct destruction of the mucosa-vasculitis could be an important additive factor to the massive GI bleeding during the anthelmintic treatment. This might result from substances released by the worms that have been killed with anthelmintic drugs. Current guidelines advise steroids to be tapered and stopped in case of systematic parasitic infections as they reduce immunity and precipitate parasitic hyperinfection. In our pinion, steroid therapy might be of value in the management of strongyloides hyperinfection related vasculitis--in addition to the specific anthelmintic treatment. Indeed, steroid therapy of vasculitis with other means of supportive care yielded in sequel of the bleeding and in recovery of the patient.  相似文献   
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