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51.
BACKGROUND: Orodental rehabilitation of hemipalatomaxillectomy defects can be accomplished by using a prosthetic obturator or a vascularized bone-containing free flap. Whereas prosthetic obturation offers several advantages, including the opportunity for immediate dental restoration without the need for further surgery, vascularized bone grafts provide permanent closure of the oronasal communication and bone sufficient for the placement of osseointegrated implants. OBJECTIVE: To compare the functional and quality-of-life (QOL) outcomes in patients rehabilitated with a prosthetic obturator with defect-matched patients who underwent reconstruction with a vascularized bone-containing free flap. METHODS: Four hemipalatomaxillectomy patients rehabilitated with a tissue-borne prosthetic obturator were compared with 4 defect-matched hemipalatomaxillectomy patients who underwent reconstruction with a vascularized bone-containing free flap. All of the patients were objectively assessed for speech, mastication, and QOL. Functional status was assessed by mastication testing, voice analysis, and nasorhinometry. Swallowing-related QOL was assessed using a patient-reported, validated swallowing QOL questionnaire, and donor site morbidity was assessed using upper extremity and lower extremity questionnaires. RESULTS: Patients who underwent reconstruction with a vascularized bone-containing free flap achieved higher mastication and speech assessment scores with less oronasal reflux than defect-matched patients rehabilitated with a prosthetic obturator. Swallowing QOL and donor site assessments demonstrated that compared with their prosthetic counterparts, reconstruction patients enjoyed a better QOL without incurring significant donor site morbidity. CONCLUSIONS: Although palatomaxillary reconstruction with vascularized bone-containing free flaps requires a second operative site, this method of orodental rehabilitation of the hemipalatomaxillectomy defect can achieve superior functional and QOL outcomes relative to defect-matched patients rehabilitated with a prosthetic obturator.  相似文献   
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OBJECTIVES: A few reports exist on hepatitis B virus (HBV) genotype distribution in Iran; however the sample sizes of these studies are insufficient. The first objective of this study was to determine the HBV genotype distribution with a large sample size (147 specimens). The second objective was to determine the incidence of the lamivudine-resistant YMDD mutant profile among HBV-infected patients not treated with lamivudine; some studies have reported that YMDD mutants are detectable even before antiviral treatment. METHODS: We used two cost-effective PCR-based methods that have been developed in-house: gap-PCR and artificially created restriction site-PCR (ACRS-PCR). Also, 11 samples were randomly selected and bi-directionally sequenced and subjected to phylogenetic analysis. RESULTS: Gap-PCR results revealed genotype D of HBV in all patients, and ACRS-PCR results disclosed the absence of mutation within the YMDD motif before antiviral therapy in the study population. Phylogenetic analysis supported the former genotyping results with the segregation of all Iranian HBV isolates in the genotype D branch with a high bootstrap value (99%, 1000 replicates). CONCLUSIONS: The present study using two cost-effective methods showed that genotype D of HBV is dominant among Iranian HBV-infected subjects, and HBV lamivudine-resistant strains do not exist naturally among Iranian patients not treated with lamivudine.  相似文献   
54.
The differential distribution of two tetrodotoxin resistant (TTXr) voltage-gated sodium channels SNS (PN3) and SNS2 (NaN) in rat primary sensory neurons has been investigated. Both channels are sensory neuron specific with SNS2 restricted entirely to those small dorsal root ganglion (DRG) cells with unmyelinated axons (C-fibers). SNS, in contrast, is expressed both in small C-fiber DRG cells and in 10% of cells with myelinated axons (A-fibers). All SNS expressing A-fiber cells are Trk-A positive and many express the vanilloid-like receptor VRL1. About half of C-fiber DRG neurons express either SNS or SNS2, and in most, the channels are colocalized. SNS and SNS2 are found both in NGF-responsive and GDNF-responsive C-fibers and many of these cells also express the capsaicin receptor VR1. A very small proportion of small DRG cells express either only SNS or only SNS2. At least four different classes of A- and C-fiber DRG neurons exist, therefore, with respect to expression of these sodium channels.  相似文献   
55.
Temporal trends in cardiogenic shock complicating acute myocardial infarction   总被引:30,自引:0,他引:30  
BACKGROUND: Limited information is available on trends in the incidence of and mortality due to cardiogenic shock complicating acute myocardial infarction. We studied the incidence of cardiogenic shock complicating acute myocardial infarction and in-hospital death rates among patients with this condition in a single community from 1975 through 1997. METHODS: We conducted an observational study of 9076 residents of metropolitan Worcester, Massachusetts, who were hospitalized with confirmed acute myocardial infarction in all local hospitals during 11 one-year periods between 1975 and 1997. Our study included periods before and after the advent of reperfusion therapy. RESULTS: The incidence of cardiogenic shock remained relatively stable over time, averaging 7.1 percent among patients with acute myocardial infarction. The results of a multivariable regression analysis indicated that the patients hospitalized during recent study years were not at a substantially lower risk for shock than patients hospitalized in the mid-to-late 1970s. Patients in whom cardiogenic shock developed had a significantly greater risk of dying during hospitalization (71.7 percent) than those who did not have cardiogenic shock (12.0 percent, P<0.001). A significant trend toward an increase in in-hospital survival among patients with cardiogenic shock in the mid-to-late 1990s was found in crude and adjusted analyses. CONCLUSIONS: Our findings indicate no significant change in the incidence of cardiogenic shock complicating acute myocardial infarction over a 23-year period. However, the short-term survival rate has increased in recent years at the same time as the use of coronary reperfusion strategies has increased.  相似文献   
56.
Adrenal tumours are either functioning or non-functioning. Non-functioning adrenal tumours are generally asymptomatic and usually of enormous proportions at the time of presentation. A case is presented here of a patient with a huge right adrenal haemangioma which was successfully treated surgically. This unusual tumour was 25 cm in diameter, was well encapsulated and weighed 4 kg. The literature pertaining to this interesting case is reviewed.  相似文献   
57.
The levels of prothrombin fragment F1+2 were measured by a double antibody radioimmunoassay in blood samples collected into different anticoagulant solutions. We evaluated healthy males between the ages of 42 and 77, asymptomatic patients with hereditary deficiencies of protein C or protein S, and persons receiving tumor necrosis factor infusions. The results in specimens collected in an anticoagulant containing ACD, EDTA, adenosine, and 25 U/ml of heparin (a) were highly correlated with those collected in an anticoagulant containing a synthetic thrombin inhibitor, EDTA, and aprotinin (b). However, in asymptomatic patients with congenital antithrombin III deficiency, we found that the plasma levels of F1+2 in blood collected in anticoagulant (a) were usually substantially higher than those collected in anticoagulant (b). We determined that this phenomenon was not attributable to the venipuncture procedure itself, but rather appears to be due to the action of low concentrations of heparin in the presence of reduced blood levels of antithrombin III. Our data show that the previously documented elevations in plasma F1+2 levels in patients with congenital antithrombin III deficiency appear to be caused by the above in vitro anticoagulant effect, and that this population does not exhibit evidence of a prethrombotic state as defined by the F1+2 assay.  相似文献   
58.

Psychometrically sound resilience outcome measures are essential to establish how health and care services or interventions can enhance the resilience of people living with dementia (PLWD) and their carers. This paper systematically reviews the literature to identify studies that administered a resilience measurement scale with PLWD and/or their carers and examines the psychometric properties of these measures. Electronic abstract databases and the internet were searched, and an international network contacted to identify peer-reviewed journal articles. Two authors independently extracted data. They critically reviewed the measurement properties from the available psychometric data in the studies, using a standardised checklist adapted for purpose. Fifty-one studies were included in the final review, which applied nine different resilience measures, eight developed in other populations and one developed for dementia carers in Thailand. None of the measures were developed for use with people living with dementia. The majority of studies (N?=?47) focussed on dementia carers, three studies focussed on people living with dementia and one study measured both carers and the person with dementia. All the studies had missing information regarding the psychometric properties of the measures as applied in these two populations. Nineteen studies presented internal consistency data, suggesting seven of the nine measures demonstrate acceptable reliability in these new populations. There was some evidence of construct validity, and twenty-eight studies hypothesised effects a priori (associations with other outcome measure/demographic data/differences in scores between relevant groups) which were partially supported. The other studies were either exploratory or did not specify hypotheses. This limited evidence does not necessarily mean the resilience measure is not suitable, and we encourage future users of resilience measures in these populations to report information to advance knowledge and inform further reviews. All the measures require further psychometric evaluation in both these populations. The conceptual adequacy of the measures as applied in these new populations was questionable. Further research to understand the experience of resilience for people living with dementia and carers could establish the extent current measures -which tend to measure personal strengths -are relevant and comprehensive, or whether further work is required to establish a new resilience outcome measure.

  相似文献   
59.
SYNOPSIS
The pattern of analgesic use, abuse and incidence of analgesic-associated nephropathy in 79 patients with chronic headache was studied. Sixty-eight of these patients had migraine. Most patients had consumed a combination of analgesics (81%) while 19% had taken single analgesics for their headache. Nonsteroidal anti-inflammatory drugs were the most commonly used analgesics (96.2%) followed by paracetamol (70.9%) and aspirin, phenacetin and caffeine compounds (5.1%). Mefenamic acid was the commonest nonsteroidal anti-inflammatory drug consumed (97.4%). Analgesic abuse which was defined as a minimum total of I kg of analgesics such as paracetamol or aspirin, phenacetin and caffeine compounds or 400 capsules/tablets of nonsteroidal anti-inflammatory drugs was noted in 65 patients. Nonsteroidal anti-inflammatory drugs were the most commonly abused analgesics (89.2%) followed by paracetamol (38.5%). Forty-five of the 65 analgesic abusers had an intravenous urogram or ultrasound performed and renal papillary necrosis was documented in one patient. Three (4.6%) of the analgesic abusers had mildly raised serum creatinine levels. Mild proteinuria of less than 1 gm/ litre was present in 27.7% of abusers. In conclusion, although analgesic use and abuse is common in patients with chronic headache, the short term incidence of analgesic-associated nephropathy (2.2%) and renal impairment (4.6%) was low. Prolonged observations will be necessary to ascertain the safety of these drugs for long term use.  相似文献   
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