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91.
92.
Although functional and clinical outcomes after total ankle arthroplasty have been promising, a steep learning curve has been recognized. In addition, the performance of concomitant hindfoot realignment procedures is controversial. The purpose of this study was to report on a single surgeon's experience with the first 50 total ankle arthroplasty procedures. We wanted to define the characteristics of the learning curve and whether the rate of complications was increased in patients who required complex reconstruction for preexistent foot and ankle deformities. This was a retrospective study of 50 cases with an average follow-up of 24.2 months. The patient population consisted of 18 men and 30 women with an average age of 57.6 years. Twenty-six percent of the cases had concomitant bony realignment procedures, while 20% had prior history of major hindfoot corrective procedures. There were 19 cases with intraoperative malleolar fractures, 12 cases that exhibited some degree of malalignment, and 6 cases of syndesmotic nonunion, and 8 ankles required early component revision. Minor wound complications that resolved with local wound care occurred in 9 cases, while 1 patient had a major wound complication requiring flap coverage. Each of these complications, other than wound complications, decreased with the surgeon's experience. Our results also indicate that the performance of major realignment procedures at the same time of implant arthroplasty is not associated with an increased incidence of complications. The results of this study suggest that total ankle arthroplasty is associated with a learning curve. Perioperative complications may potentially decrease with surgeon experience.  相似文献   
93.
OBJECTIVE: Interstitial brachytherapy is becoming an accepted treatment option for lung cancer patients for whom surgery poses a high risk. Robotic surgery has the potential to deliver brachytherapy seeds into tumors while keeping surgeons at a safe distance from the radioactive source. Our aim was to compare the accuracy, number of attempts, and time needed to place seeds next to a target when using a manual technique, video-assisted thoracoscopic surgery (VATS), and the ZEUS robot for minimally invasive surgery (MIS). METHODS: A brachytherapy seed injector was developed and attached to one of the ZEUS robotic arms. Four subjects each inserted inactive dummy brachytherapy seeds into clear agar-gelatin cubes containing a 1.6-mm stainless steel ball target. Two orthogonal radiographs were taken of each agar cube, and the corresponding distances were measured in triplicate using ImageJ processing software. The mean distance between the center of each seed and the corresponding target was calculated using the Pythagorean theorem. Comparisons were made using analysis of variance, t-tests, and Kruskal-Wallis tests, as appropriate. RESULTS: A total of 384 tests (128 for each technique) were performed. The median accuracies for the manual technique, VATS, and ZEUS were 1.8 mm (range: 0.9-6.7 mm), 2.4 mm (range: 1.0-11.3 mm), and 3.6 mm (range: 1.3-16.7 mm), respectively (p < 0.01). The median numbers of attempts for the manual technique, VATS, and ZEUS were 1 (range: 1-5), 4 (range: 1-14), and 3 (range: 1-20), respectively (p < 0.01). The median times for the manual technique, VATS, and ZEUS were 3.0 s (range: 1-43 s), 86.5 s (range: 6-372 s), and 64.5 s (range: 5-356 s), respectively (p < 0.01). CONCLUSIONS: The manual technique is the most accurate, least traumatic, and fastest method of inserting seeds into tumors. The ZEUS robotic platform was able to place seeds beside a target within a clinically acceptable distance, with an acceptable amount of trauma and time required. It achieved results equal to or better than those obtained with VATS.  相似文献   
94.
A lump on the midface of a child can pose as a diagnostic dilemma. There is a wide variety of possible differential diagnoses, ranging from simple benign conditions such as a sebaceous cyst, dermoid cyst, lipoma, neuroma and neurofibroma, to potentially devastating conditions such as odontogenic myxoma.A case of a child in which the formulation of a definite diagnosis was clinically and histologically challenging is presented.  相似文献   
95.
BACKGROUND: Systemic vascular resistance (SVR) is an integral therapeutic component of patients with heart failure and shock. We hypothesized that the ratio of the peak mitral regurgitant velocity (MRV) (m/s) to left ventricular outflow time-velocity integral (TVI(LVOT)) (cm) by Doppler would provide a noninvasive correlate of SVR. METHODS: SVR was correlated to MRV/TVI(LVOT) in 33 patients undergoing right heart catheterization. Receiver operating characteristic curves were generated to determine the best-balanced sensitivity and specificity to identify SVR > 14 Wood units (WU) and <10 WU. RESULTS: MRV/TVI(LVOT) correlated well with SVR (r = 0.842, 95% confidence interval 0.7-0.92, P <.001, Y = 0.459 + 49.397*X). By receiver operating characteristics, MRV/TVI(LVOT) > 0.27 had a 70% sensitivity and a 77% specificity to identify SVR > 14 WU. MRV/TVI(LVOT) < 0.2 had a 92% sensitivity and a 88% specificity to identify SVR < 10 WU. CONCLUSION: Doppler echocardiography provides a reliable noninvasive assessment of SVR.  相似文献   
96.
PURPOSE: To evaluate the effects of dissolvable collagen punctal plugs on the symptoms, tear stability and volume in aqueous deficient dry eyes. METHODS: Sixty-two aqueous deficient dry eye patients of mixed aetiology underwent lacrimal punctal occlusion with dissolvable collagen plugs. The subjects were randomly allocated to one of two treatment groups: group I (n = 36) had their lower puncta occluded and group II (n = 26) had both their upper and lower puncta occluded. The effectiveness of this treatment was clinically assessed by (1). scoring subject symptoms and (2). measuring the tear parameters of tear thinning time (TTT) and tear meniscus height (TMH) as indicators of tear stability and volume, respectively. Following baseline measurements, patients were reviewed at time intervals of 5 and 12 days post-occlusion. A group of age- and gender-matched normals (n = 45) was recruited for comparison (group III). RESULTS: Tear volume and stability were significantly higher in group III compared with I and II at baseline. In the treated groups on both days 5 and 12: (1). symptom score reduced significantly from a median value of 7 to 3 (p = <0.001); (2). tear stability increased significantly from a median value of 3 to 5 s by day 5 (p 相似文献   
97.
Clinical practice guidelines recommend antiviral prophylaxis to cytomegalovirus (CMV) donor-positive/recipient-negative (D+/R-) liver transplant recipients. We assessed the outcome of this strategy by determining the incidence, clinical features, and risk factors of CMV disease among CMV D+/R- liver transplant recipients who received antiviral prophylaxis. Sixty-seven CMV D+/R- liver transplant recipients (mean age+/-standard deviation: 49.5+/-11.4 years; 75% male) received oral ganciclovir [n=9 (13%)] or valganciclovir [n=58 (87%)] prophylaxis for a median duration of 92 days (interquartile range: 91-100). No breakthrough CMV disease was observed during antiviral prophylaxis. However, primary CMV disease was observed in 2%, 25%, 27%, 27%, and 29% of patients at 1, 3, 6, 12, and 24 months, respectively, after antiviral prophylaxis was stopped. The incidence of delayed-onset primary CMV disease was similar between those who received oral ganciclovir and valganciclovir. Nine (47%) patients had CMV syndrome, 8 (42%) had gastrointestinal CMV disease, and 2 (11%) had CMV hepatitis. Female patients (P=0.01) and younger age at transplant (P=0.03) were associated with an increased risk, whereas diabetes mellitus (P<0.001) was significantly associated with a lower risk of delayed-onset primary CMV disease. Allograft loss or mortality occurred in 8 (12%) patients during the median follow-up period of 3.31 (range: 0.8-5.9) years. No significant association was observed between CMV disease and patient and allograft survival. In conclusion, CMV disease remains a common complication in CMV D+/R- liver transplant patients during the contemporary era of antiviral prophylaxis. Female patients and younger patients are at increased risk of delayed-onset primary CMV disease.  相似文献   
98.
Purpose:  To determine the accuracy of distance autorefractions obtained by two 'open field' devices, the Tracey Visual Function Analyzer and the Shin-Nippon NVision-K 5001, by comparison with subjective refraction.
Methods:  Both eyes of 50 healthy phakic participants underwent subjective refraction. Autorefractions were then performed on undilated pupils using the Tracey and a modified Shin-Nippon autorefractor and these were repeated within 50 days. Agreement with subjective refraction was calculated for sphere, mean spherical equivalent (MSE) and cylindrical vectors J 0 and J 45. Intratest and intertest variability were also evaluated.
Results:  The mean age of the participants was 37.4 years. Subjective refraction MSE ranged from −6.25 D to +3.62 D, mean −0.49 D ± 1.79 D. Bias between subjective refraction and Tracey was −0.001 D, +0.045 D, +0.017 D, and −0.015 D for sphere, MSE, J 0 and J 45 respectively; these were not significant. Bias between subjective refraction and Shin-Nippon was +0.004 D, +0.033 D, +0.106 D, and −0.021 D; only the J 0 vector was significantly different ( p  < 0.0001) although this difference was small. Intratest variability for Tracey was low, measured at 0.189 D for sphere and 0.178 for MSE, and for the Shin-Nippon 0.099 D and 0.086 D respectively. Tracey intertest variability revealed small, statistically significant bias for sphere and MSE (+0.071 D and +0.070 D, p  = 0.011, 0.013). Shin-Nippon reproducibility showed no significant bias.
Conclusions:  Autorefraction measurements captured by both the Tracey and Shin-Nippon devices agree well with subjective refraction. The Shin-Nippon shows lower intratest variability.  相似文献   
99.
A series of copolymers comprising ethyl methacrylate (EM) and tetrahydrofurfuryl methacrylate (THFMA) gelled with either THFMA monomer or hydroxyethyl methacrylate (HEMA) monomer have been developed. In this paper, we examine the water uptake characteristics of the polymer systems and address the possibility of increasing the hydrophilicity of the systems by changing the ratios of the copolymers. We have investigated whether protein release from the polymers is related to the composition of the polymer systems. More protein was released from the polymers gelled with the more hydrophilic monomer (HEMA) than with THFMA. This was consistent with the calculated diffusion coefficients, which were 10 times greater for the polymers gelled with HEMA than those gelled with THFMA. Interestingly, the water uptake and protein release profiles were not dependent on the ratio of EM and THFMA in the copolymers. This is probably due to the conflicting roles of THFMA in the copolymer; it is both the more hydrophilic component as well as a cross-linking agent. In addition, it would appear that the structural and surface topography of these polymers had more significant effects on protein release than copolymer composition.  相似文献   
100.
To identify the role of protein kinase C (PKC) isoforms in multidrug resistance in tumor cells, we examined the PKC isoform pattern in the multidrug resistant P388/ADR cell line and studied the effect of down regulation of PKC isoforms on intracellular daunorubicin accumulation and P-glycoprotein expression. Using monoclonal antibodies to PKC alpha, beta and gamma and flow cytometry technique we showed that P388/ADR cells overexpressed PKC alpha and beta as compared to drug sensitive P388 cells. Prolonged treatment of P388/ADR cells with phorbol myristate acetate (PMA), a procedure that is known to down regulate PKC, resulted in the down regulation of total PKC activity and the PKC beta isoform (at the protein level) that was accompanied by the correction of daunorubicin accumulation in P388/ADR cells. The level of expression of P-glycoprotein in PMA treated cells was similar to that of untreated cells. These results suggest that PKC beta regulates the drug efflux function of P-glycoprotein.  相似文献   
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