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101.
BACKGROUND: Intraoperative parathyroid gland identification and preservation is often a challenge even in the hands of experienced surgeons as they could be indistinguishable from fat or thyroid tissue. OBJECTIVE: The goal of this study was to demonstrate the use of the Cytoscan Model E-II, which uses orthogonal polarization spectral (OPS) imaging technology, as an intravital microscope in identifying parathyroid glands intraoperatively and differentiating the parathyroid glands from fat and thyroid tissue in a rabbit model. METHODS: The necks of 4 New England white rabbits were explored with the animals under a general anesthesia. The Cytoscan was used to obtain images of the vasculature of tissue suspected to be parathyroid, fat, and thyroid tissue. These were confirmed by histologic evaluation. RESULTS: All tissues were correctly identified by the Cytoscan and confirmed by histologic analysis. There was an obvious difference in the images obtained of fatty tissue as compared with parathyroid tissues. There was also an appreciable difference between parathyroid and thyroid tissue based on the difference in vascularity. CONCLUSIONS: OPS imaging technology can be used in identifying parathyroid glands based on the difference in vascularity from fat and the pattern and density of vessels when compared with thyroid tissue in a rabbit model. Significance: The Cytoscan may play a future role in real time intraoperative identification of human parathyroid glands. Future investigation is warranted.  相似文献   
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The purpose of this study was to assess the safety and long‐term efficacy of self‐expandable stents in the treatment of benign tracheal stenosis. Nine patients (seven men) with tracheal stenosis (including one with fistula) of varied cause were treated by fluoroscopically guided balloon dilatation and stenting with self‐expandable metallic stents. The procedure was carried out under topical spray in eight patients and under general anaesthesia in one patient. The patients were followed up for a period ranging between 13 and 60 months. In eight of the nine patients, satisfactory positioning of the stent was achieved at the first instance, with immediate relief of dyspnoea. One patient with innominate artery aneurysm died 16 days after the procedure because of renal failure. At 1 month of follow up, six out of eight (75%) of our live patients were without any respiratory embarrassment. This dyspnoea‐free result reached almost 90% by the end of 1 year especially so in the fibrous strictures. Four out of the eight live patients (50%) had cough for 2 months and two (25%) had mild blood‐tinged sputum treated by inhalation and mucolytic agents. Secondary intervention was required in one patient at 1 month because of recurrent symptoms. The patient with tracheo‐oesophageal fistula required surgical intervention because of fracture of the stent. Fluoroscopically guided balloon dilatation and stenting of the tracheal stenosis is an effective non‐surgical therapy resulting in cure of fibrous strictures and palliation in cases of malignancy.  相似文献   
104.
OBJECTIVES: To determine the relative cost-effectiveness of the inhaled corticosteroids beclomethasone dipropionate (BDP), budesonide (BUD), and fluticasone propionate (FP), for managing moderate to severe asthma in adults over a one-year time horizon from the perspective of the Ministry of Health (MOH) in Canada.
METHODS: A single-arm meta-analysis of randomized control trials containing at least one of FP, BUD, and BDP was performed in order to derive estimates of effectiveness and tolerance. A decision tree analysis was then used to model the cost-effectiveness analysis. Only direct medical costs were included in the analysis (i.e., inpatient care, emergency visits, physician services, nursing services, drugs, diagnostic tests). The time horizon of the study was 52 weeks, precluding discounting. All costs are presented in 1996 Canadian dollars (CDN$). The cost-effectiveness was the cost per additional symptom-free day ($/SFD).
RESULTS: 69 of 398 articles were included in the metaanalysis. The Monte Carlo base case analysis showed that FP and BUD resulted in an annual cost of $1,383 and $1,147 respectively (p > 0.01). FP produced 216 SFDs while BUD resulted in 214 SFDs, which were not significantly different at p = 0.01 (corrected for multiple comparisons). BDP cost $1,343/year and yielded 213 SFD/year (BDP was excluded from the final analysis, dominated by BUD). With no difference in effectiveness, a cost-minimization analysis showed that BUD was the cost-effective alternative, costing $236 CDN less than the FP strategy.
CONCLUSIONS: Of the inhaled corticosteroids available on the MOH Formulary in Canada, BUD is a costeffective alternative for the treatment of adults with moderate to severe asthma.  相似文献   
105.
A population of macrophage progenitor cells, with high proliferative potential, has recently been demonstrated in postfluorouracil-treated and normal mouse bone marrow (BM) in vitro, when the newly discovered growth factor (synergistic activity, SA) is combined with a macrophage colony-stimulating factor (CSF) as a proliferative stimulus. SA, shown to be present in human spleen and placental conditioned media (HSCM and HPCM, respectively) have been studied and found to be unstable to trypsin digestion and to heating at 50 degrees C or above; stable between pH 4 and 9; nonadherent to Con-A-Sepharose; and to have an isoelectric point between pH 5 and 5.8 and a molecular weight of between 14,000 and 21,000 as indicated by gel filtration chromatography. SAs from both HSCM and HPCM have been purified 89- and 122-fold, respectively, by precipitation of extraneous proteins at pH 5 followed by chromatographing twice on Sephacryl S200. Neither of these partially purified SAs contain any CSF for mouse BM. These results indicate that the SAs from HSCM and HPCM may be closely related and that they are structurally different from CSFs derived from various murine sources that have been shown to be stable to proteolytic enzymes and heat.  相似文献   
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The use of skeletal anchorage with fixed functional appliances (FFA) has been proposed by various authors to produce skeletal changes and reduce lower incisor proclination. To compare the skeletal and dentoalveolar effects of Forsus Fatigue Resistant Device (FFRD) with or without skeletal anchorage (miniplates and mini-implants). The electronic database PubMed, Cochrane Library, Medline, Embase and Google Scholar along with a manual search of orthodontic journals till the year 2019. Only randomized control trials (RCTs) were included in the systematic review. One controlled clinical trial (CCT) which involved FFRD was included in the review since it was a continuation of an RCT which was expanded to a CCT. Skeletal and dentoalveolar outcome data were extracted to collect study characteristics. After evaluating risk of bias, the standardized mean differences (SMDs) and 95% confidence intervals (CIs) were calculated. Three RCTs and one prospective CCT were evaluated. The analysis included data from 116 Class II subjects [(58) treated with FFA along with skeletal anchorage and (58) treated with FFA]. There were no significant difference between the two groups with respect to mandibular length changes (P value = .10) and SNB angle changes (P value = .22). With respect to lower incisor inclination however, there was a significant difference between the two groups (P value = .005) signifying better results with respect to skeletal anchorage. The studies reviewed provide insufficient evidence to form a conclusion regarding the effects of the use of skeletal anchorage with FFRD. The available weak evidence suggests that the use of skeletal anchorage with FFRD has no superior skeletal effects but is able to reduce proclination of the lower incisors. Control of lower incisor proclination remains the most significant advantage of skeletal reinforcement, and miniplate-anchored FFRD showed more promising results in preventing lower incisor proclination than miniscrew-anchored FFRD.  相似文献   
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Background  

Recent evidence suggests that estrogen signaling may be involved in the pathogenesis of non-small cell lung cancer (NSCLC). Aromatase is an enzyme complex that catalyses the final step in estrogen synthesis and is present in several tissues, including the lung. In the current study we investigated the activity of the aromatase inhibitor exemestane in human NSCLC cell lines H23 and A549.  相似文献   
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