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61.
A girl aged 2 years and 8 months came to our clinic for consultation with regard to unerupted primary mandibular bilateral central incisors. An intraoral examination revealed that the teeth had not emerged into the oral cavity and showed a tooth crown morphology similar to that of the primary mandibular incisors, which appeared in the lingual submucosal area outside of the mandibular dental arch. Periapical radiographs demonstrated that the tooth crowns of both affected teeth were severely displaced to the lingual side. Computed tomography examinations were performed to clarify the three-dimensional positions of the affected teeth and their permanent successors, which revealed that the affected teeth were located in their estimated positions and had a standard root morphology. In addition, the permanent successors, which had not initiated root formation, were located close to the affected teeth. We decided to postpone extraction of the affected teeth and perform periodical examinations until the roots of the permanent successors are sufficiently formed. At the age of 2 years and 10 months, the edge of the tooth crown of the primary mandibular left central incisor was found emerged into the oral cavity. According to her parents, the patient did not complain of the emerging edge and no abnormal conditions were observed around the tooth.  相似文献   
62.
A simple two catalyst component system consisting of primary β-amino alcohols as a catalyst and amino acids as a co-catalyst put together works as an efficient organocatalyst system in the hetero Diels–Alder reaction of isatins with enones to afford the chiral spirooxindole–tetrahydropyranones in good chemical yields and stereoselectivities (up to 86%, up to 85 : 15 dr., up to 95% ee).

A simple two catalysts component system of β-amino alcohols (catalyst) and amino acids (co-catalyst) works as an efficient organocatalysts in hetero Diels–Alder reaction of isatins with enones to afford chiral spirooxindole-tetrahydropyranones.  相似文献   
63.
64.

Background

Although the combination of biliary and duodenal self-expandable metal stents (SEMS) is useful, the exacerbating effect of duodenal SEMS placement on biliary SEMS has not been documented. We conducted a multicenter retrospective study to evaluate the effect of duodenal SEMS placement on biliary SEMS.

Methods

Patients who underwent first-time biliary SEMS placement for a distal malignant biliary obstruction between September 1994 and November 2010 were included. Time to dysfunction of biliary SEMS was analyzed to identify risk factors for biliary SEMS dysfunction. Duodenal SEMS placement was analyzed as a time-dependent covariate.

Results

In total, 410 eligible patients were identified. Duodenal SEMS were placed in 33 patients (8 %). The median time to dysfunction of biliary SEMS was 170 days. Male gender (hazard ratio 1.37, 95 % confidence interval 1.03–1.83, P = 0.029) and duodenal SEMS placement (hazard ratio 2.00, 95 % confidence interval 1.16–3.45, P = 0.013) were risk factors in the multivariate Cox model. In patients undergoing duodenal SEMS, biliary SEMS dysfunction was observed in 17 (52 %) with a median time to dysfunction of 64 days after duodenal SEMS placement. As many as 60 % of the patients with biliary SEMS dysfunction after duodenal SEMS placement needed permanent percutaneous transhepatic biliary external drainage.

Conclusions

Duodenal SEMS placement is a risk factor for biliary SEMS dysfunction. Alternative methods for biliary drainage should be considered for better biliary drainage in patients with a gastric outlet obstruction.  相似文献   
65.

Background

The endoscopic ultrasound-guided rendezvous techniques (EUS-rendezvous) provide reliable biliary access after failed endoscopic retrograde cholangiopancreatography (ERCP) cannulation. We evaluated the clinical utility of an EUS-rendezvous technique using various approach routes.

Methods

Patients undergoing EUS-rendezvous for biliary access after failed bile duct cannulation in ERCP were included. EUS-rendezvous was performed via three approach routes depending on the patient’s condition: transgastric, transduodenal in a short endoscopic position, or transduodenal in a long endoscopic position. The main outcomes were the technical success rates. Secondary outcomes were procedure time and complications.

Results

Fourteen patients (median age, 77 years) underwent EUS-rendezvous for biliary access resulting from failed biliary cannulation. The reasons for biliary drainage were malignant biliary obstruction in five patients and choledocholithiasis in nine. Transgastric, transduodenal in a short position, and transduodenal in a long position EUS-rendezvous was performed in five, five, and four patients, respectively. Bile duct puncture occurred in the left intrahepatic duct in four patients, right hepatic duct in one, middle common bile duct in four, and lower common bile duct in five. The technical success rate was 100 %. In four patients, the approach route was modified from transduodenal in a short position to transduodenal in a long position or transgastric route. The median procedure time was 81 min. One case each of biliary peritonitis and pancreatitis occurred and were managed conservatively.

Conclusions

EUS-rendezvous provided safe and reliable transpapillary bile duct access after failed ERCP cannulation. The selection of the appropriate approach routes, depending on patient condition, is critical.  相似文献   
66.
PurposeThe purpose of this study was to investigate whether different types of dentures induced different responses to stimulations in sensory nerve underlying the denture-supporting mucosa using current perception threshold (CPT).Materials and methodsThe study population comprised 45 complete denture wearers with a mean age of 69.7 years (CD), 30 partial denture wearers (PD) with a mean age of 67.1 years, and 40 dentulous participants with a mean age of 69.0 years (Dent). Current perception threshold (CPT) on the greater palatine nerve at 2000 Hz, 250 Hz, and 5 Hz, corresponding to A-beta, A-delta, and C fibers respectively, were measured by the Neurometer® NS3000 device. The differences CPTs among CD, PD, and Dent groups were analyzed by Kruskal–Wallis test and Mann–Whitney U test with adjusting the multiple comparisons’ inflation of type 1 error rate by a Bonferroni correction.ResultsCPTs of CD, PD, and Dent group at 2000 Hz were 61.5 ± 45.8, 53.5 ± 25.3, 33.0 ± 11.4 (10?2 mA) respectively. CPTs of CD, PD, and Dent group at 250 Hz were 29.2 ± 28.2, 20.1 ± 13.2, 14.3 ± 5.9 (10?2 mA) respectively. CPTs of CD, PD, and Dent group at 5 Hz were 28.9 ± 23.4, 17.8 ± 12.2, 12.2 ± 5.6 (10?2 mA) respectively. The CPTs at all frequencies increased in the following order: Dent < PD < CD wearer. The statistical analyses showed that the different types of dentures significantly affected CPTs at 2000 Hz (p < 0.0001), 250 Hz (p < 0.0001), and 5 Hz (p < 0.0001).ConclusionThe different types of dentures induce different responses to stimulations in the sensory nerve underlying the denture-supporting mucosa.  相似文献   
67.

Background

Cerebral revascularization surgery (CRS) is increasingly recognized as an important component in the treatment of complex cerebral vascular disease and tumors. CRS requires that the incidence of perioperative neurological complications should be minimized, because CRS for ischemic disease is often not the goal of treatment, but rather a prophylactic surgery. CRS carries the risk of focal postoperative neurological deficits. Little has been established concerning mechanisms of post-CRS ischemia. We used 3.0-T diffusion-weighted magnetic resonance imaging (DWI) and magnetic resonance angiography (MRA) to analyze the incidence and mechanism of ischemic lesions.

Methods

We studied the anterior circulation territory after 20 CRS procedures involving 33 vascular anastomosis procedures (13 double anastomoses and 7 single anastomoses) in 12 men and 8 women between June 2007 and October 2011. The operations included single or double superficial temporal artery–middle cerebral artery (STA–MCA) anastomosis to treat internal carotid artery/MCA occlusions or severe MCA stenosis. A combined STA–MCA anastomosis and indirect bypass were performed for moyamoya disease. Postoperative DWI and MRA were obtained in all patients between 24 and 96 h after surgery to detect thromboembolism, hypoperfusion, or procedural ischemic complications and vasospasms of the donor STA.

Results

Follow-up DWI and MRA were carried out 1.8 ± 0.6 days after CRS (range, 1–4 days). Temporary occlusion time for anastomoses averaged 18.9 min (range, 16–32 min). Asymptomatic new hyperintensities occurred in the ipsilateral hemisphere of 2 patients on postoperative DWI (10% patients/6.0% anastomoses), and 1 moyamoya patient (5.0% patients/3.0% anastomoses) developed a symptomatic hyperintensity in the ipsilateral occipital lobe in response to the operation. Two abnormal small (<5 mm) cortical DWI lesions were caused by sacrifices of a small branch of the recipient MCA.

Conclusion

This study is the first postoperative 3.0-T DWI study of CRS and related clinical events. The incidence of symptomatic postoperative DWI abnormalities was restricted to 1 moyamoya patient representing 5.0% of total patients and 3.0% anastomoses. Although some postoperative DWI abnormalities occurred, CRS was found to be safe with a low risk of symptomatic ischemia.  相似文献   
68.
69.

Background

The risk of colorectal liver metastases (CLM) disappearing on cross-sectional imaging has increased with advances in preoperative chemotherapy, but <50 % of disappearing CLM demonstrate complete pathological response.

Objective

The aim of this study was to evaluate the role of fiducial marker placement before potentially curative treatment of CLM at risk of disappearing with chemotherapy.

Methods

All consecutive patients who underwent fiducial placement for tracking of CLM at a tertiary center were reviewed.

Results

Among 1377 patients undergoing CLM resection between 2005 and 2015, 35 patients underwent fiducial placement. Three patients were excluded due to disease progression. The study population comprised 32 patients who underwent fiducial placement in 41 CLM. Among the 41 marked CLM, 34 (83 %) were located >10 mm deep in the liver parenchyma, 25 (61 %) were in the right liver, and median size was 12 mm (range, 6–20 mm). No complication occurred after fiducial placement. After chemotherapy, 19 (46 %) of the 41 marked metastases disappeared on cross-sectional imaging. All fiducial-tracked CLM were treated with resection (n?=?31) or ablation (n?=?10). After median follow-up of 14 months (range, 0–64 months), no local recurrences were observed.

Conclusion

Fiducial placement represents a safe procedure that facilitates accurate localization for resection or ablation of small CLM at risk of disappearing with chemotherapy.
  相似文献   
70.

Background

The Oxford classification of IgA nephropathy consists of four markers as prognosticators. We retrospectively examined the relevance of extracapillary proliferation involving cellular and fibrocellular crescents (Ex) and arteriolar hyalinosis (A) on the long-term outcome of renal function.

Methods

A total of 314 Japanese patients who were diagnosed with IgA nephropathy, with 12 months or more of follow-up period were included in this study. A total of 186 patients were with UP ≥ 0.5 g/day. Patients with diabetes mellitus or severe kidney injury (eGFR < 30 ml/min/1.73 m2) were excluded. The presence of Ex and A were scored 0 in the absence, and 1 in the presence, of each lesion. The end point was determined as a 50 % reduction in initial eGFR or end-stage renal disease defined as eGFR < 15 ml/min/1.73 m2.

Results

In univariate analyses, the kidney survival rate was significantly lower in patients with Ex1 and A1 if UP ≥ 0.5 g/day. In the patients with UP < 0.5/day, none of the clinical and pathological parameters was determined as a risk factor. In the multivariate model including pathological parameters, Ex1 and A1 were independent risk factors for renal outcome if UP ≥ 0.5 g/day. In those patients treated with RAS-blocker or treated before introduction of methylprednisolone pulse therapy, Ex was the only independent risk factor. In multivariate analysis including clinical parameters, eGFR alone was a risk factor, due to strong correlation with other parameters.

Conclusion

Ex and A would be associated with the renal outcome of the patients with UP ≥ 0.5 g/day.
  相似文献   
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