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91.
Background: Although many factors seem to have an impact on the resonance frequency (RF) values of implants, there is a lack of evidence about some other parameters, which may have an influence on implant stability. Purpose: The aims of the study were to determine whether initial stability of a dental implant differs when the buccolingual width of the bone changes, to determine whether different orientations affect the RF measurements in the RF device, and to investigate two dental implants with different morphologies with regard to their initial stability. Materials and Methods: Two implant systems (Tidal Spiral Dental Implant Systems, Huntsville, AL, USA, and MIS Seven, MIS Implants Technologies Ltd., Shlomi, Israel) with diameters of 3.75 mm and 4.2 mm and with a length of 13 mm were used. Following the insertion of implants, buccolingual thinning of the models was performed in 2‐mm increments ranging between 0 and 8 mm. Results: A statistically significant decrease for implant stability quotient (ISQ) values was noticed for both diameters and both systems for all dimensional time points of the blocks (p < .05). The second system (more number of threads) resulted with higher ISQ values for both diameters than the first system (lower number of threads) (p < .001). The orientation of the probe influenced the measurements, where a standard orientation is advisable for the magnetic RF device. Conclusion: Different implant surface geometries seem to behave in different patterns in terms of initial stability. Dimensional changes in buccolingual direction seem to have an impact on the initial stability, where wider implants also presented higher ISQ values than narrow ones.  相似文献   
92.
The authors describe a technique for performing a safe and controlled continuous curvilinear capsulorhexis (CCC) in white cataracts using the contrast-enhancing effect of green light from an endoillumination probe. After attaching a green filter to the endoillumination unit of the vitrectomy set, a CCC was performed under the green light of the endoillumination probe, which was placed on the periphery of the cornea in a manner that followed the tearing edge of the capsulorhexis. This technique may be an alternative to capsular dyes in performing a safe and controlled CCC in white cataracts.  相似文献   
93.
Congenital arteriovenous fistula (CAVF) is a rare cardiac lesion. Angina pectoris is uncommon in younger patients with CAVF. Fistula-related symptoms, complications of this anomaly and surgical complications have a strong correlation with the age of the patient. A ten-year-old male patient with angina pectoris in whom the diagnosis of CAVF was established, and who, following surgical ligation recovered, is presented.  相似文献   
94.
Saddle nose reconstruction is based on the use of support grafts to manage aesthetic and functional problems. Bone (calvarial, iliac crest, costal, nasal hump, ulnar, and heterogeneous origin), cartilage (septal, costal, heterogeneous), and synthetic materials (silicon, silastic, polyethylene) were used as support grafts. Three patients have been included in this study to define the surgical management and long-term aesthetic and functional results of patients undergoing rhinoplasty with support grafts for a saddle nose deformity. Open rhinoplasty was employed. Both the lower turbinates were excised and the bone dissected from the soft tissues in two cases and in one case, only mucosa was removed. The amount of support needed was measured by using bone wax. The bone was used shaped in layers, according to the defect, and sutured to each other by vycril suture, and wrapped around by surgicell. The graft was then inserted in its place and fixed with external prolene sutures. Results were satisfactory in both function and aesthetics. Ten to 16-month follow-ups had no complications. Saddle nose surgery basically requires the use of a support graft to repair the nasal dorsum. A lower turbinate bone graft procedure has some advantages: it is cheap and safe, it is ready to use and not time-consuming, there is no donor area and no additional donor site morbidity, and it enlarges the airway and the passage to prevent nasal airway obstruction.  相似文献   
95.
STUDY OBJECTIVE: To compare hemodynamics, recovery profiles, early postoperative pain control and costs of total intravenous anesthesia (TIVA) with propofol and remifentanil and propofol and alfentanil. DESIGN: Randomized, double-blind study. SETTING: University hospital. PATIENTS: 40 ASA physical status I and II adult patients scheduled for lumbar discectomy. INTERVENTIONS: Patients were randomly assigned to receive either remifentanil-propofol or alfentanil-propofol. Anesthesia was induced with remifentanil 1 microg kg(-1) or alfentanil 20 microg kg(-1) with propofol 2 mg kg(-1), and maintained with infusions of propofol 150 to 100 microg kg(-1)min(-1) and either remifentanil 0.1 microg kg(-1) min(-1) or alfentanil 0.5 microg kg(-1) min(-1). MEASUREMENTS: Hemodynamic parameters (heart rate and mean arterial pressure), times to awakening, and tracheal extubation were recorded. In the postanesthesia care unit, pain level, frequency of analgesic demand, frequency of postoperative nausea and vomiting (PONV), partial oxygen saturation (SpO2), and respiratory rates were noted. Drug dosages and costs of each technique were determined. MAIN RESULTS: The mean arterial pressure significantly decreased compared to baseline values 1 minute after induction (p < 0.05) in both groups, and it significantly decreased at 5, 15, and 30 minutes perioperatively in the remifentanil group compared to the alfentanil group (p < 0.05). Time of extubation, spontaneous eye opening, and response to verbal command were similar in both groups. Visual analog scale pain scores at 30 minutes and 60 minutes were significantly lower in the alfentanil group than remifentanil group (p < 0.05). At 15, 30, and 60 minutes after terminating the operation oxygen saturation and respiratory rate were significantly higher (p < 0.05) and analgesics were required sooner in the remifentanil group than the alfentanil group (p < 0.05). The frequency of PONV was similar in both groups. The remifentanil-propofol anesthesia was found to be slightly more expensive as compared to the alfentanil based TIVA (33.41 +/- 4.53 vs. 29.97 +/- 4.1 USD) (p < 0.05). CONCLUSIONS: Both remifentanil and alfentanil provided a reasonably rapid and reliable recovery. The remifentanil-based TIVA was associated with high intraoperative cost and early postoperative pain, but it allowed a more rapid respiratory recovery.  相似文献   
96.
The authors report a rare case of a patient who had anomalous origin of left and right coronary arteries from a single coronary ostium in the right sinus of Valsalva. The stenosed right coronary artery was successfully dilated with stent implantation.  相似文献   
97.
Bone healing regulated by nitric oxide: an experimental study in rats   总被引:12,自引:0,他引:12  
Nitric oxide has many functions in wound healing and metabolism of bone. In the current study the role of nitric oxide on bone healing was investigated. Thirty-six young adult male Sprague-Dawley rats were divided into three groups: control, nitroso-bovine serum albumin, and aminoguanidine. Five millimeter segmental defects were created in the middle of the right femora. A polyethylene plate and screw posts were used for rigid fixation. Demineralized bone matrix served as the graft material in all groups. Nitroso-bovine serum albumin (an active nitric oxide congener) carried by demineralized bone matrix was applied locally at the defect in the nitroso-bovine serum albumin group. Aminoguanidine (an inducible nitric oxide synthase inhibitor) group received oral aminoguanidine treatment. Formation and healing of bone were determined by radiographic and histologic analyses. In comparison to the control group the healing rate was faster in both experimental groups as indicated by radiographic and histologic data. If accompanied by bone graft with a suitable delivery system, nitric oxide may be useful as a therapeutic adjuvant in clinical situations when local formation of bone is needed. Moreover, when combined appropriately, treatment with orthotopic nitric oxide supplementation and systemic inducible nitric oxide synthase inhibition may enhance bone healing.  相似文献   
98.
Exposure to endotoxin has been associated with an exacerbation of asthmatic responses in humans and animal models. However, recent evidence suggests that microbial exposure in early life may protect from the development of asthma and atopy. In this study, we sought to evaluate the effects of lipopolysaccaride (LPS) on airway function in developing mice. In addition, we evaluated the influence of LPS on subsequent allergen sensitization and challenge. Under light anesthesia, 2-3-week-old Balb/c mice received a single intranasal instillation of LPS or sterile physiologic saline. Measurements of airway function were obtained in unrestrained animals, using whole-body plethysmography. Airway responsiveness was expressed in terms of % enhanced pause (Penh) increase from baseline to aerosolized methacholine (Mch). In additional studies, we assessed the functional and cellular responses to ovalbumin sensitization and challenge following prior exposure to LPS.We found that exposure to LPS induced transient airway hyperresponsiveness to Mch. These functional changes were associated with the recruitment of neutrophils and lymphocytes into the bronchoalveolar lavage (BAL) fluid. Airway responsiveness after allergen sensitization and challenge was decreased by prior exposure to LPS. The analysis of BAL cells and cytokines (interferon-gamma and interleukin-4) did not reveal alterations in the overall Th1/Th2 balance.Our findings suggest that LPS leads to airway hyperresponsiveness in developing mice, and may protect against the development of allergen-driven airway dysfunction.  相似文献   
99.
100.
The authors report a case of alveolar soft-part sarcoma with lung metastases demonstrated by "double imaging" with Tc-99m HDP and Tc-99m MIBI. The tumor originated in the soft tissue with direct invasion to the right scapula, which was hypoactive on bone scan and hyperactive on Tc-99m MIBI images. A focus of dense accumulation of Tc-99m MIBI in the lungs, suggesting metastasis was also demonstrated.  相似文献   
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