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991.
Jin Ho Hong Ha Young Lee Myung Kwan Lim Mi Young Kim Young Hye Kang Kyung Hee Lee Soon Gu Cho 《Korean journal of radiology》2013,14(6):960-962
Cri-du-Chat syndrome, also called the 5p-syndrome, is a rare genetic abnormality, and only few cases have been reported on its brain MRI findings. We describe the magnetic resonance imaging findings of a 1-year-old girl with Cri-du-Chat syndrome who showed brain stem hypoplasia, particularly in the pons, with normal cerebellum and diffuse hypoplasia of the cerebral hemispheres. We suggest that Cri-du-Chat syndrome chould be suspected in children with brain stem hypoplasia, particularly for those with high-pitched cries. 相似文献
992.
Doo Kyoung Kang Yongsik Jung Sehwan Han Ji Young Kim Tae Hee Kim 《Ultrasound in medicine & biology》2017,43(2):412-420
This study evaluated the usefulness of magnetic resonance (MR)-navigated ultrasound (US) for evaluation of magnetic resonance imaging (MRI)-detected lesions not visible on second-look US and analyzed differences in lesion-to-nipple distance between supine and prone positions. Of the 831 consecutive patients who were diagnosed with breast cancer and examined with breast MRI from June 2013 to September 2015, 40 lesions in 37 patients who underwent MR-navigated US for MRI-detected lesions that were not visible on second-look US were included. First, MRI was performed in a prone position using a 1.5-T imager, and second, MRI was performed in a supine position for MR-navigated US. Of 40 lesions, 31 (78%) were identified with MR-navigated US, whereas 5 (13%) lesions disappeared on supine MRI and 4 (10%) exhibited no correlation on MR-navigated US. Of 31 lesions with pathologic confirmation, 7 (23%) were malignant, 2 (6%) were high-risk lesions and 22 (71%) were benign lesions. Comparison of the US findings of benign and malignant lesions revealed that orientation of the lesion differed significantly (p = 0.045), whereas lesion shape, margin and echo pattern did not significantly differ between the two groups (p = 0.088, p = 0.094 and p = 0.412, respectively). Median difference in lesion-to-nipple distance on supine and prone MRI was 8 mm (0–34 mm) in the horizontal direction and 5 mm (0–39.5 mm) in the vertical direction. Thirteen lesions exhibited a >1-cm difference in both horizontal and vertical directions. In conclusion, MR-navigated US was useful for the evaluation of MRI-detected lesions that were not visible on second-look US in breast cancer patients. 相似文献
993.
Melvin D. Helgeson Daniel G. Kang Ronald A. Lehman Anton E. Dmitriev Scott J. Luhmann 《The spine journal》2013,13(8):957-965
Background contextThere is currently no reliable technique for intraoperative assessment of pedicle screw fixation strength and optimal screw size. Several studies have evaluated pedicle screw insertional torque (IT) and its direct correlation with pullout strength. However, there is limited clinical application with pedicle screw IT as it must be measured during screw placement and rarely causes the spine surgeon to change screw size. To date, no study has evaluated tapping IT, which precedes screw insertion, and its ability to predict pedicle screw pullout strength.PurposeThe objective of this study was to investigate tapping IT and its ability to predict pedicle screw pullout strength and optimal screw size.Study designIn vitro human cadaveric biomechanical analysis.MethodsTwenty fresh-frozen human cadaveric thoracic vertebral levels were prepared and dual-energy radiographic absorptiometry scanned for bone mineral density (BMD). All specimens were osteoporotic with a mean BMD of 0.60±0.07 g/cm2. Five specimens (n=10) were used to perform a pilot study, as there were no previously established values for optimal tapping IT. Each pedicle during the pilot study was measured using a digital caliper as well as computed tomography measurements, and the optimal screw size was determined to be equal to or the first size smaller than the pedicle diameter. The optimal tap size was then selected as the tap diameter 1 mm smaller than the optimal screw size. During optimal tap size insertion, all peak tapping IT values were found to be between 2 in-lbs and 3 in-lbs. Therefore, the threshold tapping IT value for optimal pedicle screw and tap size was determined to be 2.5 in-lbs, and a comparison tapping IT value of 1.5 in-lbs was selected. Next, 15 test specimens (n=30) were measured with digital calipers, probed, tapped, and instrumented using a paired comparison between the two threshold tapping IT values (Group 1: 1.5 in-lbs; Group 2: 2.5 in-lbs), randomly assigned to the left or right pedicle on each specimen. Each pedicle was incrementally tapped to increasing size (3.75, 4.00, 4.50, and 5.50 mm) until the threshold value was reached based on the assigned group. Pedicle screw size was determined by adding 1 mm to the tap size that crossed the threshold torque value. Torque measurements were recorded with each revolution during tap and pedicle screw insertion. Each specimen was then individually potted and pedicle screws pulled out “in-line” with the screw axis at a rate of 0.25 mm/sec. Peak pullout strength (POS) was measured in Newtons (N).ResultsThe peak tapping IT was significantly increased (50%) in Group 2 (3.23±0.65 in-lbs) compared with Group 1 (2.15±0.56 in-lbs) (p=.0005). The peak screw IT was also significantly increased (19%) in Group 2 (8.99±2.27 in-lbs) compared with Group 1 (7.52±2.96 in-lbs) (p=.02). The pedicle screw pullout strength was also significantly increased (23%) in Group 2 (877.9±235.2 N) compared with Group 1 (712.3±223.1 N) (p=.017). The mean pedicle screw diameter was significantly increased in Group 2 (5.70±1.05 mm) compared with Group 1 (5.00±0.80 mm) (p=.0002). There was also an increased rate of optimal pedicle screw size selection in Group 2 with 9 of 15 (60%) pedicle screws compared with Group 1 with 4 of 15 (26.7%) pedicle screws within 1 mm of the measured pedicle width. There was a moderate correlation for tapping IT with both screw IT (r=0.54; p=.002) and pedicle screw POS (r=0.55; p=.002).ConclusionsOur findings suggest that tapping IT directly correlates with pedicle screw IT, pedicle screw pullout strength, and optimal pedicle screw size. Therefore, tapping IT may be used during thoracic pedicle screw instrumentation as an adjunct to preoperative imaging and clinical experience to maximize fixation strength and optimize pedicle “fit and fill” with the largest screw possible. However, further prospective, in vivo studies are necessary to evaluate the intraoperative use of tapping IT to predict screw loosening/complications. 相似文献
994.
Association of low baseline free thyroxin levels with progression of coronary artery calcification over 4 years in euthyroid subjects: the Kangbuk Samsung Health Study 下载免费PDF全文
995.
996.
Woo Beom Shin Min Kyo Kim Christopher Seungkyu Lee Sung Chul Lee Hyesun Kim 《Korean journal of ophthalmology : KJO》2015,29(6):389-395
PurposeTo compare clinical, angiographic, and optical coherence tomographic characteristics between eyes with acute Vogt-Koyanagi-Harada (VKH) disease and eyes with acute bilateral central serous chorioretinopathy (CSC), and to demonstrate distinguishing features between the two diseases in confusing cases.MethodsThe medical records of 35 patients with VKH disease and 25 patients with bilateral CSC were retrospectively reviewed. Characteristics according to slit-lamp biomicroscopy, ophthalmoscopy, fundus photography, fluorescein angiography, indocyanine green angiography, and spectral-domain optical coherence tomography were compared between the two diseases.ResultsFive of 35 patients (10 of 70 eyes, 14.3%) with VKH disease were initially misdiagnosed as CSC patients, and six of 25 patients (12 of 50 eyes, 24%) with bilateral CSC were initially misdiagnosed as patients with VKH disease. Pigment epithelial detachment in CSC and optic disc hyperemia in VKH disease show the highest positive predictive values of 100% for each disease.ConclusionsOptic disc hyperemia in VKH disease and pigment epithelial detachment in bilateral CSC are the most specific clinical manifestations of each disease at initial patient presentation. 相似文献
997.
998.
999.
Jing-Yi Tan Xue-Qin Chen Bi-Jun Kang Zi-Xi Qin Jia-Hong Chen Ren-Dong Hu Liang-Cai Wu 《Asian Pacific journal of tropical medicine》2018,(3)
Objective: To explore the therapeutic effect and mechanism of myricctin on disseminated intravascular coagulation(DIC). Methods: The DIC model was established by injection of60 mg/kg LPS in KM mice, and the treatment groups were injected myricetin with different concentrations(25 or 50 mg/kg) 30 min before the model was established. Both coagulation indicators and organ function were tested, including PT, APTT, fibrinogen. AST, ALT. BUN and tissue section. In vitro, the inflammatory model of RAW 264.7 macrophage cells were established by 10 μg/mL LPS. The treatment group was treated with 50 μmol/mL myricetin for 30 min before LPS, and the expression of TNF-a and p-NF-KB was detected, further to explore the therapeutic mechanism. Results: LPS-induced DIC led to a reduction of fibrinogen and a rise of PT, APTT,AST, ALT, BUN levels, but the treatment of myricctin significantly inhibited these abnormalities. Histopathology analysis also revealed that myricetin remarkably protected the liver and renal damage. In vitro, the expression of TNF-α and p-NF-κB induced by LPS was repressed by myricetin. Conclusions: This study provides new insights into the protective effects of myricetin in LPS-induced DIC by anticoagulant and anti-inflammatory via suppressing the activation of p-NF-κB which decreased TNF-α level. 相似文献
1000.