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91.
Graefe's Archive for Clinical and Experimental Ophthalmology - To assess the effect of pan-retinal photocoagulation (PRP) on choroidal vascular parameters in eyes with advanced diabetic...  相似文献   
92.
Graefe's Archive for Clinical and Experimental Ophthalmology - This study was conducted to investigate factors related to postoperative good near and distance visual outcomes in the Lentis...  相似文献   
93.
ObjectiveThe use of direct lumbar interbody fusion (DLIF) has gradually increased; however, no studies have directly compared DLIF and transforaminal lumbar interbody fusion (TLIF). We compared DLIF and TLIF on the basis of clinical and radiological outcomes.MethodsA retrospective review was performed on the medical records and radiographs of 98 and 81 patients who underwent TLIF and DLIF between January 2011 and December 2012. Clinical outcomes were compared with a visual analog scale (VAS) and the Oswestry disability index (ODI). The preoperative and postoperative disc heights, segmental sagittal/coronal angles, and lumbar lordosis were measured on radiographs. Fusion rates, operative time, estimated blood loss (EBL), length of hospital stay, and complications were assessed.ResultsDLIF was superior to TLIF regarding its ability to restore disc height, foraminal height, and coronal balance (p<0.001). As the extent of surgical level increased, DLIF displayed significant advantages over TLIF considering the operative time and EBL. However, fusion rates at 12 months post-operation were lower for DLIF (87.8%) than for TLIF (98.1%) (p=0.007). The changes of VAS and ODI between the TLIF and DLIF were not significantly different (p>0.05).ConclusionBoth DLIF and TLIF are less invasive and thus good surgical options for treating degenerative lumber diseases. DLIF has higher potential in increasing neural foramina and correcting coronal balance, and involves a shorter operative time and reduced EBL, in comparison with TLIF. However, DLIF displayed a lower fusion rate than TLIF, and caused complications related to the transpsoas approach.  相似文献   
94.
The need for standard endovascular neurosurgical (ENS) training programs and certification in Korea cannot be overlooked due to the increasing number of ENS specialists and the expanding ENS field. The Society of Korean Endovascular Neurosurgeons (SKEN) Certification Committee has prepared training programs and certification since 2010, and the first certificates were issued in 2013. A task force team (TFT) was organized in August 2010 to develop training programs and certification. TFT members researched programs and systems in other countries to develop a program that best suited Korea. After 2 years, a rough draft of the ENS training and certification regulations were prepared, and the standard training program title was decided. The SKEN Certification Committee made an official announcement about the certification program in March 2013. The final certification regulations comprised three major parts: certified endovascular neurosurgeons (EN), certified ENS institutions, and certified ENS training institutions. Applications have been evaluated and the results were announced in June 2013 as follows: 126 members received EN certification and 55 hospitals became ENS-certified institutions. The SKEN has established standard ENS training programs together with a certification system, and it is expected that they will advance the field of ENS to enhance public health and safety in Korea.  相似文献   
95.

Purpose

Premature physeal closure of the proximal femoral physis has been reported in Legg-Calve-Perthes Disease (LCPD). However, the timing of its occurrence had not yet been reported. We proposed (1) to determine the timing of premature physeal closure in unilateral LCPD with serial radiographic evaluation, and (2) to evaluate the relationship between the premature physeal closure and Herring classification, leg-length discrepancy (LLD), Stulberg classification, and trochanteric overgrowth.

Methods

We performed a retrospective study with serial radiographs of 27 patients diagnosed with LCPD. The difference in the timing of physeal closure between the hips was calculated. The involved hip was classified according to Herring classification. The LLD and ATD index at latest follow up was measured. The mean values were calculated and statistical comparison of variables was done using the Fisher’s exact test.

Results

The mean difference of physeal closure at the involved hip compared to the uninvolved side was 3.5 years (range, two to five years). Hips demonstrating premature physeal closure were associated with Herring B/C and C (p?=?0.01) and LLD >1 cm (p?=?0.02). There is no correlation between Stulberg classification, trochanteric overgrowth and premature physeal closure (p?=?0.06 and p?=?0.19).

Conclusions

We may expect premature physeal closure of the proximal femoral physis in patients with LCPD to occur 3.5 years earlier than normal hips. Presence of premature physeal closure can be an adjunct diagnostic tool in the prognostication of LCPD outcomes. Future studies directed toward premature physeal closure in LCPD and associated growth disturbances are necessary.  相似文献   
96.

Background

Spleen-preserving laparoscopic distal pancreatectomy (SPLDP) can be performed with splenic vessel resection (SVR) or splenic vessel preservation (SVP). The purpose of this comparative study was to evaluate the clinical outcomes of patients who underwent SPLDP with SVR or SVP at a single institution.

Methods

We retrospectively reviewed the records of 246 patients who underwent SPLDP at Asan Medical Center, Seoul, Korea, for benign or low-grade malignant tumors found in the body or tail of the pancreas between November 2005 and November 2011.

Results

In total, 206 patients (83.7 %) were managed by SVP. SVR was performed in the remaining 40 (16.3 %) cases. There were no significant differences between the SVP and SVR groups in terms of intraoperative blood loss (378 ± 240 vs. 328 ± 204 ml, respectively; P = 0.240) and operating time (193.4 ± 59.1 vs. 204.4 ± 51.8 min, respectively; P = 0.492). Sixty-seven (32.5 %) and 10 patients (25 %) had complications in the SVP and SVR groups, respectively (P = 0.347). At 3 days after surgery, the rates of splenic infarction were 16.0 % (33/206) in the SVP group and 52.5 % (21/40) in the SVR group, but all recovered within 12 months on postoperative computed tomography. The time of recovery from splenic infarction was 3.6 ± 3.1 and 4.7 ± 3.7 months in the SVP and SVR groups, respectively. At 6 months, the rates of gastric varices were 1.9 % in the SVP group and 35 % in the SVR group (P < 0.001) with no progression at 12 months. No gastrointestinal bleeding occurred at a median follow-up of 34 months (range = 12–84).

Conclusions

SPLDP with SVR can be used for patients with large and benign or low-grade malignant tumors that distort and compress vessel course, as the higher rate of early splenic ischemia and perigastric varices is acceptable.  相似文献   
97.

Purposes

Diabetes mellitus (DM) is thought to be an important aetiological factor in intervertebral disc degeneration. A glucose-mediated increase of oxidative stress is a major causative factor in development of diseases associated with DM. The aim of this study was to investigate the effect of high glucose on mitochondrial damage, oxidative stress and senescence of young annulus fibrosus (AF) cells.

Methods

AF cells were isolated from four-week-old young rats, cultured, and placed in either 10 % FBS (normal control) or 10 % FBS plus two different high glucose concentrations (0.1 M and 0.2 M) (experimental conditions) for one and three days. We identified and quantified the mitochondrial damage and reactive oxygen species (ROS) (oxidative stress). We also identified and quantified the occurrence of senescence and telomerase activity. Finally, the expressions of proteins were determined related to replicative senescence (p53-p21-pRB) and stress-induced senescence (p16-pRB).

Results

Two high glucoses enhanced the mitochondrial damage in young rat AF cells, which resulted in an excessive generation of ROS in a dose- and time-dependent manner for one and three days compared to normal control. Two high glucose concentrations increased the occurrence of senescence of young AF cells in a dose- and time-dependent manner. Telomerase activity declined in a dose- and time-dependent manner. Both high glucose treatments increased the expressions of p16 and pRB proteins in young rat AF cells for one and three days. However, compared to normal control, the expressions of p53 and p21 proteins were decreased in young rat AF cells treated with both high glucoses for one and three days.

Conclusions

The present study demonstrated that high glucose-induced oxidative stress accelerates premature stress-induced senescence in young rat AF cells in a dose- and time-dependent manner rather than replicative senescence. These results suggest that prevention of excessive generation of oxidative stress by strict blood glucose control could be important to prevent or to delay premature intervertebral disc degeneration in young patients with DM.  相似文献   
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