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1.
Direct visualization of crystal growth in poly(L ‐lactide) thin films was carried out by using a temperature‐controlled atomic force microscopy (AFM). At the initial stage of crystallization, edge‐on lamellar crystals have nucleated and elongated. Subsequently, the edge‐on lamellar crystals showed S‐shaped morphology and changed their orientation from edge‐on manner to flat‐on one. The curvature of edge‐on lamellar crystal has been discussed in terms of inclination and distortion of polymer chains in the crystal. In addition, mechanism on the formation of flat‐on crystal from edge‐on lamellae was proposed as derivative growth on the basis of in situ AFM observation of crystal growth and enzymatic degradation.

  相似文献   

2.
In recent years, resections of midline skull base tumors have been conducted using endoscopic endonasal skull base (EESB) approaches. Nevertheless, many surgeons reported that cerebrospinal fluid (CSF) leakage is still a major complication of these approaches. Here, we report the results of our 42 EESB surgeries and discuss the advantages and limits of this approach for resecting various types of tumors, and also report our technique to overcome CSF leakage. All 42 cases involved midline skull base tumors resected using the EESB technique. Dural incisions were closed using nasoseptal flaps and fascia patch inlay sutures. Total removal of the tumor was accomplished in seven pituitary adenomas (33.3%), five craniopharyngiomas (62.5%), five tuberculum sellae meningiomas (83.3%), three clival chordomas (100%), and one suprasellar ependymoma. Residual regions included the cavernous sinus, the outside of the intracranial part of the internal carotid artery, the lower lateral part of the posterior clivus, and the posterior pituitary stalk. Overall incidence of CSF leakage was 7.1%. Even though the versatility of the approach is limited, EESB surgery has many advantages compared to the transcranial approach for managing mid-line skull base lesions. To avoid CSF leakage, surgeons should have skills and techniques for complete closure, including use of the nasoseptal flap and fascia patch inlay techniques.  相似文献   
3.
Abstract. Group B and AB sera, acting on O red cells in the presence of UDP-galactose, each converted them into B active cells, which were agglutinated by anti-B human serum (1:512) at the titer of 128-fold, while group Bm and A1 Bm sera, converted O red cells similarly incubated into B active cells, which were agglutinated by anti-B human serum (1:512) at the titer of 8- to 16-fold. This indicates that α-galactosyltransferase activity in Bm and A1 Bm sera may be about ⅛-⅙ that in B and AB sera. Group CisAB sera, even after absorption of cold anti-B agglutinins with packed, washed group B red cells, did not convert O red cells in the presence of UDP-galactose in such a way that they might agglutinate against anti-B human serum.  相似文献   
4.
3-Chloro-4-(dichloromethyl)-5-hydroxy-2(5 H )-furanone (MX) is known as a by-product of wood pulp manufacture and a contaminant of chlorinated drinking water. Since our previous studies (Teramoto et al., 1998, 1999) demonstrated in a micromass in vitro test a strong inhibitory effect of MX on rat embryo cell differentiation, the potential teratogenicity was investigated in this study by using a suspension organ culture system. Twelve-day mouse embryo palatal explants were cultivated for 72 hr in the MX-containing medium at a concentration of 0, 1, 10, 100 or 300 μg/ml and examined for closure of the palatal shelves. All control explants showed almost complete closure of the palatal shelves. Similar results were also obtained in the MX-treated explants at concentrations up to and including 100 μg/ml. Immunohistochemistry revealed no difference between the control and MX-treated explants in distribution of PCNA-and TUNEL-positive cells in the palatal mesenchyme and medial edge epithelium, respectively. When the MX concentration was raised to 300 μg/ml, palatal shelves remained wide open. However, histopathology revealed extensive pyknosis of the mesenchymal cells and loss of the epithelium. These results may indicate that MX is cytotoxic against the mouse palate at a high concentration, and that it has no cleft-palate inducing effects in mice.  相似文献   
5.
6.
Case report Focal cortical dysplasia (FCD) with calcification is rare. We presented a 13-year-old epileptic patient with FCD and calcification in the left frontal lobe. At age 24, the FCD lesion and the surrounding epileptogenic cortex and underlying subcortex were removed after chronic subdural electrode recording. Histological examination showed that the calcified lesion was not independent of the FCD lesion but located in the subcortical area of the FCD lesion. A neoplastic nature was ruled out for the lesion. Discussion The pathophysiological mechanism involved in the coexistence of FCD and calcification is discussed.  相似文献   
7.
Abstract: We studied a 57-year-old man who was diagnosed as having giant rugae at a mass-screening for gastric cancer. He was examined endoscopically for check-up purposes. In addition to giant rugal folds which occurred throughout the entire fundus and body of the stomach, a type IIc lesion was noted in the posterior lower wall of the gastric body. A biopsy revealed signet ring cell carcinoma. A total gastrectomy was performed. A resected specimen was serially sectioned and underwent histopathological examination; hypertrophy and cystic elongation of the gastric glands indicative of so-called giant hypertrophic gastritis was seen. The histological type of the type IIc lesion was undifferentiated adenocarcinoma with the signet ring cells being confined to the mucosal layer. This patient had a rare case of Menetrier's disease complicated by intramucosal carcinoma.  相似文献   
8.
Abstract: Specific types of early gastric cancer were investigated in accordance with the cancer surface area and the degree of penetration by means of quantitative measurements of the surface area of early gastric cancer using the interactive image analysis system. The results indicated a significant correlation between the surface area and the penetration depth in ordinary early gastric cancer. However these correlations were not observed in both well and poorly differentiated adenocarcinoma cases of the so-called PEN and SUPER types, which showed a significant specificity when compared with ordinary early gastric cancer. The PEN and SUPER types of early gastric cancer also exhibited various clinicopathological characteristics, and it was suggested that the poorly differentiated PEN type might be the initial lesion of a linitis plastica type gastric cancer. Examination of the conditions of the mucosa surrounding the cancer revealed a difference between the PEN and the SUPER types, and this suggested that the environment at the site of a cancer growth influences the type of growth and the spread of early gastric cancer.  相似文献   
9.

Background

It remains unclear whether early surgical intervention can reduce mortality after surgery in hip fracture patients. The aim of this study was to investigate the association between time from injury to surgery and mortality rate within 90 days after hip fracture surgery.

Methods

We retrospectively identified 1827 patients who underwent hip fracture surgery in a tertiary care center in Japan between April 2007 and March 2017. After applying exclusion criteria (patients with spontaneous fracture, multiple fractures, revision surgery, total hip arthroplasty, or a refusal to participate), 1734 patients were included. We extracted data concerning patients’ age, race, sex, operative procedure, American Society of Anesthesiologists (ASA) score, days from injury to surgery (injury-surgery days), and days from admission to surgery (admission-surgery days), which could affect 90-day mortality after surgery. Variables associated with 90-day mortality were determined using multivariate logistic regression analysis.

Results

The 90-day postoperative mortality rate was 3.5% (60 of 1734). Multivariable analysis showed that injury-surgery days were not associated with 90-day mortality (odds ratio [OR], 0.91; 95% confidence interval [CI], 0.80 to 1.05; P = 0.19), and that older age (OR, 1.06; 95% CI, 1.02 to 1.10; P = 0.005), male sex (OR, 3.62; 95% CI, 1.86 to 7.03; P < 0.001) and high ASA score (OR, 2.10; 95% CI, 1.06 to 4.18; P = 0.034) significantly increased 90-day mortality. In addition, admission-surgery days were not associated with 90-day mortality (OR, 0.95; 95% CI, 0.83 to 1.09; P = 0.45).

Conclusion

Our results demonstrated that time from injury to surgery was not associated with mortality within 90 days after surgery after adjusting for age, sex, operative procedure, and ASA score.  相似文献   
10.
The purpose of this study was to analyze the effect of obesity on outcomes after continuous-flow left ventricular assist device (CF-LVAD) implantation. A single-center retrospective analysis was performed on 526 chronic heart failure patients who were implanted with the HeartMate II CF-LVAD (n?=?403) or HeartWare HVAD (n?=?123) between November 2003 and March 2016. Patients were stratified into 4 groups based on BMI: underweight (<?18.5 kg/m2, n?=?18, 3.4%), normal-weight (18.5–25 kg/m2, n?=?173, 32.9%), overweight (25–30 kg/m2, n?=?182, 30.2%), and obese (>?30 kg/m2, n?=?153, 33.5%). The underweight group was excluded because of its small sample size. Records were reviewed to determine the incidence of postoperative complications and survival. Survival at 1, 6, 12, and 24 months were similar among normal-weight (91.3, 84.4, 76.3, and 67.6%), overweight (90.4, 80.8, 76.5, and 69.6%), and obese patients (90.7, 74.7, 65.3, and 61.3%, p?=?0.24). Additionally, obesity was not a significant predictor of mortality in Cox proportional hazard models (hazard ratio 0.98, 95% confidence interval 0.766–1.277, p?=?0.13). These findings suggest that appropriately selected obese patients receive similar survival benefit from CF-LVADs compared to non-obese patients, and obesity should not serve as a contraindication to CF-LVAD implantation.  相似文献   
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