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This discussion on developments within publishing presents further thought on green, gold and hybrid models of open access. It also discusses some of the advantages and disadvantages which may be encountered by researchers, authors, institutions, scientific organisations and publishers.  相似文献   

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This single-center prospective trial evaluated the safety and efficacy of percutaneous sclerotherapy for liver hemangiomas in 5 patients (1 man, 4 women; mean age 41.2 y) between 2016 and 2017. All patients were symptomatic (4 abdominal pain; 1 early satiety) and refused surgery. A single session of sclerotherapy with 20 cc mixture of 45 IU. Bleomycin in 10 cc distilled water and 10 cc Lipiodol (Ultra Fluide, Guerbet, France) was performed in all patients, achieving a 45.6%–71.1% lesion volume reduction and a 12.9%–41% reduction in the largest diameter of the lesion. Symptoms subsided in all patients during the 5-month follow-up period. Adverse events included a self-limited intraperitoneal hemorrhage in 1 patient.  相似文献   

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We investigated the effect of in vivo degradation for 6-12 weeks on the fixation strength of polylactide bioabsorbable interference screws. Ten bioabsorbable interference screws were used to fix the patellar tendon autograft in ten live sheep knees, which were equally divided into two groups and killed in the 6th or 12th week. The control group consisted of four cadaveric knees. Following the killing of the animals the screws were retrieved and reused to fix patellar tendon grafts in cadaveric sheep knees. Tendon pull-out tests were performed for the partially degraded screws, for the control group, and for the reused screws of the control group. Macroscopic and microscopic examinations of the 6- and 12-week specimens were performed. Tendons pulled-out with an average force of 357+/-30 N in the cadaveric control group on the first use and with 465+/-118 N on the second use. The partially degraded screws failed with a mean load of 399+/-119 N in the 6-week group, and 12-week screws at 447+/-72 N. No macroscopic sign of degradation was observed on the retrieved screws. Histological examination of the 6 week specimens showed necrotic changes in the tendon around screw contact areas. Healing with granulation tissue was present in the same area in the 12th week. Foreign body reaction or an excessive inflammatory reaction was not observed. In vivo degradation of poly- l-lactide interference screws for 12 weeks thus causes neither a loss in the fixation strength of the screws nor an obvious inflammatory reaction.  相似文献   

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The purpose of this study was to evaluate high-resolution (HR) myocardial first-pass perfusion in healthy volunteers at 3 T compared to a typical clinical imaging protocol at 1.5 T, with respect to overall image quality and the presence of subendocardial dark rim artifacts. Myocardial first-pass rest perfusion studies were performed at both field strengths using a T1-weighted saturation-recovery segmented k-space gradient-echo sequence combined with parallel imaging (Gd-DTPA 0.05 mmol/kg). Twenty-six healthy volunteers underwent (1) a HR perfusion scan at 3 T(pixel size 3.78 mm2) and (2) a standard perfusion approach at 1.5 T(pixel size 9.86 mm2). The contrast enhancement ratio (CER) and overall image quality (4-point grading scale: 4: excellent; 1: non-diagnostic) were assessed, and a semiquantitative analysis of dark rim artifacts was performed for all studies. CER was slightly higher (1.31 ± 0.32 vs. 1.14 ± 0.34; p<0.01), overall image quality was significantly improved (3.03 ± 0.43 vs. 2.37 ± 0.39; p<0.01), and the number of dark rim artifacts (139 ± 2.09 vs. 243 ± 2.33; p<0.01) was significantly reduced for HR perfusion imaging at 3 T compared to the standard approach at 1.5 T. HR myocardial rest perfusion at 3 T is superior to the typical clinical perfusion protocol performed at 1.5 T with respect to the overall image quality and presence of subendocardial dark rim artifacts.  相似文献   

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Purpose

To perform a systematic review and meta-analysis of published studies to evaluate the efficacy of lymphatic interventions for chylothorax.

Materials and Methods

The MEDLINE, EMBASE, and Cochrane databases were searched for English-language studies until March 2017 that included patients with chylothorax treated with lymphangiography (LAG), thoracic duct embolization (TDE), or thoracic duct disruption (TDD). Exclusion criteria were as follows: a sample size of less than 10 patients, no extractable data, or data included in subsequent articles or duplicate reports.

Results

The cases of 407 patients from 9 studies were evaluated. The pooled technical success rates of LAG and TDE were 94.2% (95% confidence interval [CI], 88.4%–97.2%; I2 = 46.7%) and 63.1% (95% CI, 55.4%–70.2%; I2 = 37.3%), respectively. The pooled clinical success rates of LAG, TDE, and TDD, on a per-protocol basis, were 56.6% (95% CI, 45.4%–67.2%; I2 = 5.4%), 79.4% (95% CI, 64.8%–89.0%; I2 = 68.1%), and 60.8% (95% CI, 49.4%–71.2%; I2 = 0%), respectively. The pooled major complication rate of LAG and TDE was 1.9% (95% CI, 0.8%–4.3%; I2 = 0%) and 2.4% (95% CI, 0.9%–6.6%; I2 = 26.4%), respectively. The pooled overall clinical success rate of lymphatic interventions, on an intention-to-treat basis, was 60.1% (95% CI, 52.1%–67.7%; I2 = 54.3%). Etiology of chylothorax was identified as a significant source of heterogeneity for the pooled clinical success rate of TDE and overall clinical success rate.

Conclusions

Lymphatic interventions have a respectable efficacy for the treatment of chylothorax.  相似文献   

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Purpose

To evaluate noise level and contrast-to-noise ratio (CNR) with various kVp-mAs pairs producing the same computed tomography dose index (CTDI) value. The 80 kVp and new 70-kVp settings were compared.

Materials and methods

The noise was measured in 10 ovoid water phantoms with different diameters from 10 cm to 28 cm. Contrast was obtained from CTs of iodine-filled tubes. Spiral acquisition protocols at 70 kVp and 80 kVp, with the same CTDI, were applied. In the clinical study, two matched groups, each of 21 paediatric patients, underwent 70-kVp or 80-kVp ECG-gated iodinated-enhanced sequential CT.

Results

Noise was significantly higher with 70 kVp than 80-kVp settings for all phantom sizes. Estimated CNR with phantoms was higher at 70 kVp than 80 kVp, and the difference decreased from 17 % to 3 % as phantom size increased. The mean CNR in paediatric patients was 15.2 at 70 kVp and 14.3 at 80 kVp (ns). The CNR difference was significantly larger in the small-child subgroup.

Conclusion

Noise level is slightly higher at the 70-kVp than the 80-kVp setting, but the CNR is higher, particularly for small children. Therefore, 70 kVp may be appropriate for contrast-enhanced CT examinations and 80 kVp for non-enhanced CT in small children.

Key Points

? 70-kVp settings provide a slightly higher noise level compared to 80-kVp settings. ? The CNR is higher with 70-kVp than with 80-kVp settings. ? Without contrast, 80-kVp settings may be preferable over 70-kVp settings.  相似文献   

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Purpose

To prospectively assess feasibility, safety, and cytoreductive effect of transarterial chemoembolization on renal cell carcinoma (RCC) using drug-eluting embolic agent (DEE) saturated with doxorubicin compared with transarterial embolization (TAE).

Materials and Methods

Between 2012 and 2015, 12 patients (male/female = 5/7, age 66 y ± 9.8) with biopsy-verified RCC eligible for nephron-sparing surgery or radical nephrectomy were recruited. Mean tumor size was 3.2 cm ± 0.62. Patients were randomized at 1:1 ratio to receive either DEE transarterial chemoembolization or TAE before planned surgery. A microcatheter was used to inject particles selectively into arteries feeding the tumors. Response was evaluated by CT according to modified Response Evaluation Criteria In Solid Tumors and by microscopy of excised tumors. Complications were scored according to the Society of Interventional Radiology classification.

Results

DEE transarterial chemoembolization (n = 6) resulted in a significantly (P = .018) higher degree of necrosis with an average of 88.3% (range, 70%–100%) compared with TAE (n = 5), which resulted in an average of 29.4% (range, 0–77%), as evaluated by CT. Histopathologic evaluation showed similar results (P = .016) with an average necrosis of 87.5% (range, 80%–95%) for DEE transarterial chemoembolization (n = 4) versus 26% (range, 0–70%) for TAE (n = 5). Percentage of necrosis seen on microscopy correlated significantly (P = .0005) with radiologic findings, as 4 tumors in each arm were evaluated by both CT and microscopy. No major complications were observed in either group.

Conclusions

DEE transarterial chemoembolization is safe for treating localized RCC and has a significantly superior cytoreductive effect compared with TAE.  相似文献   

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PurposeThe purpose of this study is to introduce the aortic bulge sign, a finding observed retrospectively on computed tomography prior to the acute presentation of aortoenteric fistula, and to determine its interobserver reliability.MethodsFollowing research ethics board approval, all cases of aortoenteric fistula at our institution occurring from 2011–2015 were identified retrospectively. All previous computed tomography images of patients who eventually developed aortoenteric fistula were reviewed by a single observer for the presence of a potentially predictive finding of fistulization, the aortic bulge sign. These previous images were then combined with age and sex matched controls into a case bank. Eight radiology residents and staff were instructed in observing the aortic bulge sign. These observers then reviewed the case bank in a blinded analysis to determine the interobserver reliability of this finding.ResultsFourteen cases of aortoenteric were identified. The average patient age was 70.71 years with a male-to-female ratio of 11:3. Eleven patients had previous computed tomography images available for review. With blinded analysis by multiple observers, the aortic bulge sign was identified with greater than 80% agreement in six of 11 cases (66.67%). Fleiss' kappa was calculated at k = 0.60 (95% confidence interval 0.50–0.69), corresponding to moderate-to-substantial interobserver agreement.ConclusionsThe aortic bulge sign has been retrospectively identified as a promising computed tomography finding of eventual aortoenteric fistula prior to acute presentation. Further study is required to determine the diagnostic value of this sign.  相似文献   

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