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21.
Wax interocclusal records of five subjects made during three types of mandibular closing movement at various degrees of jaw opening were successively placed between mandibular and maxillary casts that were mounted on an articulator. Recording pins inserted into the lateral sides of the casts were used to record the amount of movements. The rotation centers were then calculated and the following results were obtained. (1) For the terminal hinge closure in which the mandible was guided by the chinpoint, no statistically constant rotation center was observed. (2) For the most retruded closure of the mandible in which each subject was asked to make the most retruded position by his own effort, a constant rotation center was found in two of five subjects. (3) For habitual closure of the mandible no constant rotation center was observed, and where the interocclusal distance was less than 1 mm the mandible seemed to close perpendicular to the occlusal plane.  相似文献   
22.
Vascular changes in full-thickness skin grafts in rats were examined at various intervals after grafting using microangiography. The grafted skin and its bed showed dynamic vascular changes that were considered to be related to release of an " angiogenetic factor" produced by the skin under oxygen-deficient conditions such as ischemia. The first filling of contrast medium in the grafts was observed 24 hours after grafting. Both primary and secondary revascularization were observed.  相似文献   
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OBJECTIVES: To determine the effect of different combinations of surface conditioning (DeTrey Conditioner 36, NRC, no etching) and restorative materials (Dyract AP, Spectrum TPH) on the shear bond strength of Prime and Bond NT to enamel and dentin, and to characterize the resin-dentin interface produced by these combinations. METHODS: Shear bond strength was tested on 30 enamel and 30 dentin flat labial surfaces of extracted bovine teeth. The enamel and dentin specimens were randomly assigned to six groups of five teeth each and treated using different combinations of surface conditioners and restorative materials with Prime and Bond NT. Scanning electron microscope (SEM) observation of argon-ion-etched specimens was done to evaluate the resin-dentin interface. RESULTS: The type of surface conditioning and restorative material had significant effects on dentin bond strengths. Etching the dentin prior to application of Prime and Bond NT significantly increased bond strength and caused formation of a hybrid layer for Spectrum TPH. For Dyract AP, dentin etching generally did not improve bond strength despite the formation of a hybrid layer. On enamel, Prime and Bond NT had consistently high bond strengths on etched specimens. SIGNIFICANCE: The results showed that Dyract AP and Spectrum TPH, when used with Prime and Bond NT have different bonding mechanisms and the effect of surface conditioning on their shear bond strength differs. Clinicians should be aware of these effects in order to optimize bonding.  相似文献   
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26.
To overcome the problems associated with sheet- or film-type anti-adhesive materials, we developed a new type of anti-adhesive material, gelatin flakes. We made two types of gelatin flakes with or without thermal cross-linking, and preliminarily examined their basic properties and the anti-adhesive efficacy using a rodent adhesion model. Both types of the gelatin flakes rapidly turned into gel and tightly attached the injured surfaces, absorbing the moisture and blood, when applied onto the abraded sites of rats. In addition, these flakes could be sprayed into the desired area by compressed air through a device with a long, thin tube, which could be used in laparoscopic surgery. The anti-adhesive effects of both types of gelatin flakes were similar, and both types were significantly superior compared to the non-treated group. Although further investigations are necessary, the gelatin flakes have unique and useful properties and satisfactory anti-adhesive effects, which indicate that they may be applicable in laparoscopic surgery.  相似文献   
27.

Background

Mutations of POLR3A and POLR3B have been reported to cause several allelic hypomyelinating disorders, including hypomyelination with hypogonadotropic hypogonadism and hypodontia (4H syndrome). Patients and methods: To clarify the difference in MRI between the two genotypes, we reviewed MRI in three patients with POLR3B mutations, and three with POLR3A mutations. Results: Though small cerebellar hemispheres and vermis are common MRI findings with both types of mutations, MRI in patients with POLR3B mutations revealed smaller cerebellar structures, especially vermis, than those in POLR3A mutations. MRI also showed milder hypomyelination in patients with POLR3B mutations than those with POLR3A mutations, which might explain milder clinical manifestations. Conclusions: MRI findings are distinct between patients with POLR3A and 3B mutations, and can provide important clues for the diagnosis, as these patients sometimes have no clinical symptoms suggesting 4H syndrome.  相似文献   
28.
Graefe's Archive for Clinical and Experimental Ophthalmology - The aim of this study was to analyze choroidal structures in healthy subjects and patients with/without diabetic macular edema...  相似文献   
29.
A less invasive transsphenoidal approach with a keyhole dural opening for intrasellar arachnoid cysts is described. This approach was used to address seven sellar cystic lesions with suprasellar extension; they were six intrasellar arachnoid cysts (IACs) and one Rathke’s cleft cyst (RCC). In all cases, preoperative MRI revealed cerebrospinal fluid (CSF) intensity on both T1- and T2-weighted images. On preoperative contrast-enhanced MRI, five of the six IACs manifested posterior displacement of the flattened pituitary gland toward the dorsum sellae; one of the six IACs and the RCC exhibited a flattened pituitary gland on the anterior surface of the cyst. Wide cyst cisternostomy through a keyhole dural opening was carried out safely using a microscope with the support of a thin angled endoscope (30° and/or 70°, diameter 2.7 mm). As we aimed to avoid iatrogenic injury of the pituitary function, we found it difficult to obtain a sufficiently wide and precise opening of the cyst wall when the pituitary gland was located on the anterior surface of the cyst wall. Our approach facilitates safe cyst cisternostomy as wide as that obtainable by transcranial manipulation. In addition, CSF leakage is prevented by dural plasty using the fascia lata and stitching with 6-0 monofilament sutures. This technique can be adapted to address various sellar cystic lesions. However, as the posterior or anterior displacement of the normal pituitary gland in the presence of IACs or RCCs, respectively, affects the width of the cyst opening, our technique is more suitable for IACs than RCCs.  相似文献   
30.

Background

We showed in a previous study that pylorus-resecting pancreaticoduodenectomy (PrPD), which divides the stomach adjacent to the pylorus ring, preserves more than 95 % of the stomach and significantly reduced the incidence of delayed gastric emptying (DGE) compared with pylorus-preserving pancreaticoduodenectomy (PpPD). However, long-term outcomes of PrPD and the adverse effect of early postoperative DGE on long-term outcomes remain unclear.

Methods

A total of 130 patients enrolled in a previous study were followed for 24 months after surgery. Primary endpoint was whether PrPD is a better surgical procedure than PpPD regarding long-term outcomes.

Results

Weight loss > grade 2 (Common Terminology Criteria for Adverse Events, Version 4.03) at 24 months after surgery was significantly better in group PrPD (16.2 %) than in group PpPD (42.2 %) (p = 0.011). Nutritional status and late postoperative complications were similar for the two groups. The incidence of weight loss > grade 2 at 24 months was 63.6 % in DGE patients with DGE and 25.3 % in non-DGE patients (p = 0.010). T max (time to peak 13CO2 content in 13C-acetate breath test) at 24 months in DGE patients was significantly delayed compared with that in non-DGE patients (27.9 ± 22.7 vs. 16.5 ± 10.1 min, p = 0.023). Serum albumin level at 24 months was higher in non-DGE patients than in those with DGE (3.7 ± 0.6 vs. 4.1 ± 0.4 g/dl, p = 0.013).

Conclusions

PrPD offers long-term outcomes similar to those of PpPD. DGE may be associated with weight loss and poor nutritional status in patients with long-term outcomes.  相似文献   
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