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101.
BackgroundIt is essential to understand the mechanism of the various causes of laser fiber damage and an ideal method of reducing endoscope damage induced by laser emission in multiple sites. This study classified the different patterns of laser fiber degradation according to laser settings and analyzed the role of cavitation bubbles to find a desirable way of minimizing endoscope damage.MethodsA total of 118 laser fibers were analyzed after 1-,3-, and 5-min laser emission to artificial stones under the settings of 1 J-10 Hz, 1 J-20 Hz, 1 J-30 Hz, and 2 J-10 Hz. Every 3 cm from the fiber tip was marked and examined with a digital microscope and a high-speed camera. The images of the fibers and the movement of cavitation bubbles were taken with a distance of 1 to 5 mm from the gel.ResultsSeven types of fiber damage (charring, limited and extensive peeled-off, bumpy, whitish plaque, crack, and break-off) coincided during laser emission. Damages rapidly increased with emission time > 3 minutes regardless of the laser settings. The damaged lengths covered 5 mm on average, and the fibers at 5-min emission were significantly shorter than others. The fiber durability of 1J-10Hz setting was better than other settings after 3-min laser emission. Backward movement of the cavitation bubbles was found at the 1-mm distance from the gel, and the damaged lengths were longer than the diameters of the cavitation bubbles because of their proximal movement.ConclusionThe damage patterns of the laser fiber tips were classified into seven types. The heat damage around the surface of the laser fiber can be increased according to the high-energy or high-frequency laser setting, a short distance to the stone, a short distance from the tips of flexible ureteroscopes, no cutting laser fiber procedures, and the inappropriate use of irrigation fluid or laser fiber jacket.  相似文献   
102.
BackgroundAlthough ankle fractures are among the most common fractures, nationwide population-based data on the epidemiology of patients with ankle fractures are scarce. This study aimed to perform an epidemiological analysis of all ankle fractures in Korea from 2010 through 2018.MethodsWe used national registries from the Korean Health Insurance Review and Assessment Service from 2009 to 2018. The annual incidence of the ankle fracture was calculated. The incidence was also calculated according to gender and age. Trends of fracture subtypes were also analyzed. Then, the incidence of ankle fractures by seasonal variation was investigated.ResultsA total of 735,073 ankle fractures were identified in 461,497,758 people for 10 years. The annual incidence of ankle fracture was 171.37/100,000 persons in 2018, with a male to female ratio of 0.78. Interesting differences in the ankle fracture trends were observed between gender. Male shows the highest incidence in adolescence, and the even distribution has lasted for the rest of their lives. In females, the incidence of ankle fracture showed an increasing tendency as their age increased. There was a clear difference in the incidence rate of each season according to age. Ankle fractures occurred more in spring and autumn in children and adolescents and most in winter in the elderly.ConclusionAnkle fracture risk was different between sex and exhibited seasonal variations. Our findings can be used for epidemiological awareness and prevention campaigns for ankle fractures.  相似文献   
103.
ObjectiveTransvenous embolization (TVE) via an occluded inferior petrosal sinus (IPS) in a cavernous sinus dural arteriovenous fistula (CSDAVF) is challenging, often requiring navigation of a microcatheter through resistive obstacles between the occluded IPS and shunted pouch (SP), although the reopening technique was successfully performed. We report five cases of successful access to the cavernous sinus (CS) or SP using the rigid-tipped microguidewire such as chronic total occlusion (CTO) wire aiming to share our initial experience with this wire. MethodsIn this retrospective study, four patients with CSDAVF underwent five procedures using the CTO wire puncture during transfemoral transvenous coil embolization. Puncture success, shunt occlusion, and complications including any hemorrhage and cranial nerve palsy were evaluated. ResultsDespite successful access through the occluded IPS, further entry into the target area using neurointerventional devices was impossible due to a short-segment stricture before the CS (three cases) and a membranous barrier within the CS (two cases). However, puncturing these structures using the rigid-tipped microguidewire was successful in all cases. We could advance the microcatheter over the rigid-tipped microguidewire for the navigation to the SP and achieved complete occlusion of the SP without complications. ConclusionThe use of the rigid-tipped microguidewire in the TVE via the occluded IPS of the CSDAVF would be feasible and safe.  相似文献   
104.
ObjectiveTo conduct a simulation study to determine whether artificial intelligence (AI)-aided mammography reading can reduce unnecessary recalls while maintaining cancer detection ability in women recalled after mammography screening.Materials and MethodsA retrospective reader study was performed by screening mammographies of 793 women (mean age ± standard deviation, 50 ± 9 years) recalled to obtain supplemental mammographic views regarding screening mammography-detected abnormalities between January 2016 and December 2019 at two screening centers. Initial screening mammography examinations were interpreted by three dedicated breast radiologists sequentially, case by case, with and without AI aid, in a single session. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and recall rate for breast cancer diagnosis were obtained and compared between the two reading modes.ResultsFifty-four mammograms with cancer (35 invasive cancers and 19 ductal carcinomas in situ) and 739 mammograms with benign or negative findings were included. The reader-averaged AUC improved after AI aid, from 0.79 (95% confidence interval [CI], 0.74–0.85) to 0.89 (95% CI, 0.85–0.94) (p < 0.001). The reader-averaged specificities before and after AI aid were 41.9% (95% CI, 39.3%–44.5%) and 53.9% (95% CI, 50.9%–56.9%), respectively (p < 0.001). The reader-averaged sensitivity was not statistically different between AI-unaided and AI-aided readings: 89.5% (95% CI, 83.1%–95.9%) vs. 92.6% (95% CI, 86.2%–99.0%) (p = 0.053), although the sensitivities of the least experienced radiologists before and after AI aid were 79.6% (43 of 54 [95% CI, 66.5%–89.4%]) and 90.7% (49 of 54 [95% CI, 79.7%–96.9%]), respectively (p = 0.031). With AI aid, the reader-averaged recall rate decreased by from 60.4% (95% CI, 57.8%–62.9%) to 49.5% (95% CI, 46.5%–52.4%) (p < 0.001).ConclusionAI-aided reading reduced the number of recalls and improved the diagnostic performance in our simulation using women initially recalled for supplemental mammographic views after mammography screening.  相似文献   
105.
Four new 3-methyl-4-ethylideneproline-containing peptides, lucentamycins A-D (1-4), have been isolated from the fermentation broth of a marine-derived actinomycete identified by phylogenetic methods as Nocardiopsis lucentensis (strain CNR-712). The planar structures of the new compounds were assigned on the basis of 1D and 2D NMR spectroscopic techniques, while the absolute configurations of the amino acid residues were determined by application of the advanced Marfey method. Lucentamycins A (1) and B (2) showed significant in vitro cytotoxicity against HCT-116 human colon carcinoma.  相似文献   
106.
Eucommia ulmoides Oliv. Bark (EUE) is commonly used for the treatment of hypertension, rheumatoid arthritis, lumbago, and ischialgia as well as to promote longevity. In this study, we tested the effects of EUE aqueous extract in graded doses to protect and enhance cognition in scopolamine-induced learning and memory impairments in mice. EUE significantly improved the impairment of short-term or working memory induced by scopolamine in the Y-maze and significantly reversed learning and memory deficits in mice as measured by the passive avoidance and Morris water maze tests. One day after the last trial session of the Morris water maze test (probe trial session), EUE dramatically increased the latency time in the target quadrant in a dose-dependent manner. Furthermore, EUE significantly inhibited acetylcholinesterase (AChE) and thiobarbituric acid reactive substance (TBARS) activities in the hippocampus and frontal cortex in a dose-dependent manner. EUE also markedly increased brain-derived neurotrophic factor (BDNF) and phosphorylation of cAMP element binding protein (CREB) in the hippocampus of scopolamine-induced mice. Based on these findings, we suggest that EUE may be useful for the treatment of cognitive deficits, and that the beneficial effects of EUE are mediated, in part, by cholinergic signaling enhancement and/or protection.  相似文献   
107.
Angiogenesis is important for promoting cardiovascular disease, wound healing, and tissue regeneration. We investigated the effects of Korean red ginseng water extract (KRGE) on angiogenesis and its underlying signal mechanism. KRGE increased in vitro proliferation, migration, and tube formation of human umbilical vein endothelial cells, as well as stimulated in vivo angiogenesis without increasing VEGF expression. KRGE-induced angiogenesis was accompanied by phosphorylation of ERK1/2, phosphatidylinositol 3-kinase (Akt), and endothelial nitric oxide synthase (eNOS) as well as an increase in NO production. Inhibition of PI3K activity by wortmannin completely inhibited KRGE-induced angiogenesis and phosphorylation of Akt, ERK1/2, and eNOS, indicating that PI3K/Akt activation is an upstream event of the KRGE-mediated angiogenic pathway. The MEK inhibitor PD98059 blocked KRGE-induced ERK1/2 phosphorylation without affecting Akt and eNOS activation. However, the eNOS inhibitor N(G)-monomethyl-L-arginine effectively inhibited tube formation, but partially blocked proliferation and migration as well as ERK phosphorylation, without altering Akt and eNOS activation, revealing that the eNOS/NO pathway is partially involved in ERK1/2 activation. This study demonstrated that KRGE stimulates in vitro and in vivo angiogenesis through the activation of the PI3K/Akt-dependent ERK1/2 and eNOS signal pathways and their cross talk.  相似文献   
108.
AIM:To evaluate the efficacy of Seprafilm? transplantation following adhesiolysis for preventing postoperative readhesion and improving surgical outcomes.METHODS:Primary blepharoplasty was carried out on both eyelids of 18 albino rabbits. After 2 weeks, a new skin incision was made, and adhesiolysis was performed on both eyelids. The rabbits were categorized into two groups, one with adhesiolysis alone in the left eyelid (control group), and the other with adhesiolysis with a Seprafilm? graft in the right eyelid (Seprafilm? group). The degrees of inflammation and fibrosis were examined with hematoxylin-eosin (HE) and Masson’s trichrome stains. Expression of α-smooth muscle actin (α-SMA) was also immunohistochemically examined.RESULTS:Eyelid examination immediately after the operation revealed mild swelling and hemorrhage in both groups, but these symptoms resolved after 1 week-2 weeks, and eyelid shape had recovered completely in both groups. Microscopic assessments demonstrated that the Seprafilm? group showed less inflammation and fibrosis than the control group. The Seprafilm? group also exhibited fewer α-SMA-positive cells than the control group.CONCLUSION:Based on these findings, we conclude that Seprafilm? graft with adhesiolysis is an effective method for preventing postoperative readhesions after eyelid surgery.  相似文献   
109.
BACKGROUND: Imatinib is effective for a variety of hematologic and nonhematologic malignancies. Well-known ocular side effects are periorbital edema, epiphora, extraocular muscle palsy, and blepharoconjunctivitis. However, optic disc edema has not been reported as a complication of imatinib mesylate. Herein, we describe a patient with chronic myeloid leukemia (CML) who developed optic disc edema during treatment with imatinib. CASE: A 14-year-old Korean girl was referred to ophthalmology for a 3-week history of photopsia in both eyes. She had started taking imatinib daily 2 months previously for CML. At the initial exam, slit lamp showed optic disc edema in both eyes, even though visual acuity was 20/20 and other optic nerve function evaluations were within normal limits. We recommended to the oncologist discontinuation of the imatinib treatment. OBSERVATIONS: When the patient was followed for 1 week after stopping imatinib treatment, the frequency of photopsia decreased and the optic disc edema improved. Because a second examination 3 weeks after discontinuation of imatinib revealed much improved optic disc edema, she restarted the imatinib treatment. No ocular side effects have been noted so far. CONCLUSIONS: Optic disc edema should be considered one of the complications associated with imatinib. We propose discontinuation of the treatment for a short period when optic disc edema occurs.  相似文献   
110.

Purpose

We investigated the effect of muscle relaxants (atracurium) on the outcomes of intermittent exotropia surgery under general anesthesia, with a focus on resection procedures.

Methods

Thirty four patients who underwent recession and resection (R&R) were divided into two groups: atracurium usage (group A, n=18) and no atracurium usage (group B, n=16). Patients were divided into two subgroups according to the amount of resection of the medial rectus (MR): less than 5 mm (group 1, n=13) or 5 mm and greater (group 2, n=21). Deviation angles were compared between groups and subgroups. Surgical outcome was defined as successful if distant deviation angles were equal to or less than 10 prism diopters.

Results

The overall postoperative deviation angles did not show statistically significant differences between groups A and B. However, in patients with larger MR resections (≥ 5 mm), the 1 week postoperative distant deviation was significantly larger in group A (1.8±2.6 PD) than in group B (-1.6±4.6 PD, p=0.048 by t-test). The overall undercorrection rate at 3 months postoperatively for group A was 16.7%, which was higher than that of group B (6.3%), and the difference was even larger in subgroups with larger MR resections (≥ 5 mm): 18.2% in group A and 0% in group B.

Conclusions

Patients who underwent R&R procedures under general anesthesia with a muscle relaxant tended to be less corrected than those without muscle relaxant, especially in the early postoperative period and with a larger MR resection equal to or greater than 5 mm. However, there was no significant difference in the later postoperative period.  相似文献   
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