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91.
Photoreduction of Cu2+ ions to Cu metal by titanium(IV) oxide (TiO2) was conducted in the presence of a silica–surfactant hybrid under sulfuric acid conditions. After irradiation, a dark-red color, reflections due to Cu metal in the X-ray diffraction pattern, and peaks due to Cu 2p1/2 and 2p3/2 in the X-ray photoelectron spectrum indicated the precipitation of Cu metal in the product. In addition, an increase in the Brunauer–Emmett–Teller specific surface area from 36 and 45 m2/g for the silica–surfactant and TiO2, respectively, to 591 m2/g for the product, and a decrease in the intensity of the C-H stretching band in the Fourier–transform infra-red spectra implied the removal of surfactant during the reaction. These characteristics were never observed when TiO2 was used solely. Therefore, this study indicated that the photoreduction of Cu2+ ions to Cu metal by TiO2 was facilitated under the sulfuric acid medium, where the surfactants extracted from silica–surfactant hybrids by protons in the acidic condition were successfully photo-oxidized by TiO2. Thus, this study presents a new application of the conversion of a silica–surfactant hybrid into mesoporous silicas.  相似文献   
92.

Objectives

The purpose of this study was to compare the degree of colorectal distention between manual insufflation using room air and automatic insufflation using carbon dioxide for computed tomography colonography performed as a preoperative examination for patients with colon cancer.

Materials and methods

Participants comprised 200 patients who underwent computed tomography colonography immediately after colonoscopy from October 2011–2012. The first 100 patients were examined using manual insufflation, and the remaining 100 patients were examined using automated insufflation. Two radiologists independently assessed colorectal distention using a 4-point scale in six segments: cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum. Mean scores of the two radiologists were used to analyze whether any differences existed between techniques in terms of the degree of distention per segment.

Results

Mean distention values for the colonic lumen were better using the automated technique than with the manual technique in both positions (p < 0.05). In segments, distention was significantly better using the automated technique than using the manual technique in the sigmoid and descending colon for prone patients, and in all segments for supine patients.

Conclusions

Automated carbon dioxide insufflation offered significantly improved colorectal distention scores compared to manual room air insufflation.  相似文献   
93.
Purpose: To determine the trends with fatally or otherwise injured pedestrians lying on the road and the relationship to hit-and-run incidents in Japan. Methods: We extracted data for 2012e2016 from the records of the Institute for Traffic Accident Research and Data Analysis, Japan, a nationwide traffic accident database. All the injured and fatally injured pedestrians were selected. We examined the levels of pedestrian injury, vehicle speed immediately before the collision, whether or not the pedestrian was lying on the road, and hit-and-run incidents. Chi-square test was employed to make a statistical comparison between the two groups. Results: The database contained data on 286,383 pedestrian casualties and 7256 fatalities; 8.3% of fatalities (602 persons) and 0.6% of casualties (1827 persons) involved pedestrians lying on the road. The rates of fatalities and severe injuries were significantly higher for pedestrians who were lying on the road than for those who were not. Hit-and-run incidents were evident in 4.0% of casualties and 7.3% of fatalities. The rate of hit-and-run cases was also significantly higher among pedestrians who were lying on the road. Among fatally injured pedestrians not lying on the road, the rates with speeds of 30 km/h did not differ significantly between hit-and-run and other cases. However, when the pedestrians were lying on the road, the rate was significantly increased in hit-and-run cases. Conclusion: This is the first report to focus on pedestrians lying on the road and being involved in hitand-run incidents. In addition to preventing hit-and-run incidents, prevention of pedestrians lying on the road could also decrease fatalities.  相似文献   
94.
Li-air batteries have attracted considerable attention as rechargeable secondary batteries with a high theoretical energy density of 11,400 kWh/g. However, the commercial application of Li-air batteries is hindered by issues such as low energy efficiency and a short lifetime (cycle numbers). To overcome these issues, it is important to select appropriate cathode materials that facilitate high battery performance. Carbon materials are expected to be ideal materials for cathodes due to their high electrical conductivity and porosity. The physicochemical properties of carbon materials are known to affect the performance of Li-air batteries because the redox reaction of oxygen, which is an important reaction for determining the performance of Li-air batteries, occurs on the carbon materials. In this study, we evaluated the effect of the surface modification of carbon cathode materials on the charge–discharge performance of Li-air batteries using commercial Ketjenblack (KB) and KB subjected to vacuum ultraviolet (VUV) irradiation as cathodes. The surface wettability of KB changed from hydrophobic to hydrophilic as a result of the VUV irradiation. The ratio of COOH and OH groups on the KB surface increased after VUV irradiation. Raman spectra demonstrated that no structural change in the KB before and after VUV irradiation was observed. The charge and discharge capacities of a Li-air battery using VUV-irradiated KB as the cathode decreased compared to original KB, whereas the cycling performance of the Li-air battery improved considerably. The sizes and shapes of the discharge products formed on the cathodes changed considerably due to the VUV irradiation. The difference in the cycling performance of the Li-air battery was discussed from the viewpoint of the chemical properties of KB and VUV-irradiated KB.  相似文献   
95.
Background: It has been reported that cystine and theanine, amino acids related to glutathione synthesis, have immunomodulatory effects, such as suppressing inflammation after strenuous exercise. In this study, we examined the effects of oral administration of cystine and theanine during the perioperative period as a pilot study. Methods: Forty‐three cases of distal gastrectomy for cancer conducted in our department were assigned to the cystine and theanine group (CT group) or to the placebo control group (P group), and a randomized, single‐blind, parallel‐group study was then performed. Cystine (700 mg) and theanine (280 mg) or a placebo was administered to participants for 10 continuous days (4 days before to 5 days after surgery). Changes in pre‐ and postoperative interleukin (IL)–6, C‐reactive protein (CRP), albumin, white blood cell (WBC) count, neutrophil count, total lymphocyte count, resting energy expenditure (REE), and body temperature were compared and examined. Results: Ten patients were excluded, leaving 33 patients in the study. The CT group had significantly lower IL‐6 values (postoperative day [POD] 4), CRP levels (POD 7), neutrophil counts (POD 4), and body temperatures (POD 5) than the P group (P < .05). In addition, REE in the P group peaked on day 1 (1.14 ± 0.16 [pre‐ and postoperative ratio]), whereas the CT group did not show any increase on POD 1 (0.99 ± 0.21, P < .05 vs P group). Conclusions: This study suggests that oral administration of cystine and theanine during the perioperative period may alleviate postgastrectomy inflammation and promote recovery after surgery.  相似文献   
96.
Purpose Motion artifact is problematic in the diagnosis of Creutzfeldt-Jakob disease (CJD) because of dementia. The purpose was to compare the occurrence of this artifact between a diffusion-weighted (DW) magnetic resonance (MR) imaging sequence and conventional sequences. Materials and methods Ten MR examinations comprising T2-weighted, T1-weighted, DW, and fluid-attenuated inversion recovery imaging in seven CJD patients were retrospectively evaluated. The occurrence of motion artifacts on each sequence were assessed, and the examination was classified into four groups as follows: group A, motion artifact not revealed on DW imaging but revealed on one or more other sequences; group B, revealed on DW imaging and one or more other sequences; group C, not revealed on any sequences; and group D, revealed on DW imaging but not on any other sequences. Results The 10 MR examinations were classified as eight group A (80%), one B (10%), one C (10%), and zero D (0%). Conclusion Motion artifacts are likely to occur in any conventional imaging sequences in CJD, but the fast-imaging ability of DW imaging can reduce this artifact. The combination of an absence of motion artifact on DW imaging and the presence on conventional sequences may be one of the frequent findings of CJD.  相似文献   
97.
Symptomatic volar subluxation of the abductor pollicis longus and the extensor pollicis brevis tendons developed in a 29-year-old man after a sprain that occurred with the wrist in flexion and ulnar deviation. The extensor retinaculum, which forms the extensor compartment, was partially avulsed from its insertion on the radius. Palmar abduction and extension of the thumb with the wrist flexed produced subluxation of the tendons over the volar side of the radius ridge where the retinaculum forming the first extensor compartment attached. Nonoperative treatment including steroid injection and splinting was ineffective. Surgery was performed to reconstruct a new tendon restraint with part of the extensor retinaculum.  相似文献   
98.
Abstract. Background/Purpose: Although curative surgical resection provides the best chance of long-term survival for patients with intrahepatic cholangiocarcinoma, the presence of bile duct invasion decreases postoperative survival rates in patients with mass-forming intrahepatic cholangiocarcinoma. We carried out this study to determine a surgical strategy for patients with bile duct invasion of these tumors. Methods: Forty-one patients with mass-forming intrahepatic cholangiocarcinoma were classified as either having bile duct invasion (n= 26) or not having bile duct invasion (n= 15). Clinicopathologic findings, including postoperative outcomes, were compared between these two groups. Results: Perineural invasion, lymphatic invasion, and a positive resection margin were more frequent in patients with ductal invasion. Patients with ductal invasion had lower survival rates than those without ductal invasion. Conclusions: Intraoperative frozen section examination of the bile duct stump to confirm a clear resection margin is required in patients with mass-forming tumors. Resection of the extrahepatic bile duct should be considered when tumor cells are identified at the surgical margin of the resected bile duct. Received: October 30, 2001 / accepted: November 16, 2001  相似文献   
99.
 The aim of this study was to clarify the relationship between endogenous estrogen, sex hormone-binding globulin (SHBG), and bone loss in pre-, peri-, and postmenopausal female residents of Taiji, a rural Japanese community. From a list of inhabitants aged 40 to 79 years, 200 participants—50 women in each of four age decades—were randomly selected, and baseline bone mineral density (BMD) at the lumbar spine and proximal femur were measured by dual-energy X-ray absorptiometry in 1993. Total estradiol (total E2) and SHBG were measured, and SHBG-unbound E2 (UBE2) was calculated using SHBG and the percent SHBG-unbound fraction ratio. BMD was measured again 3 years later, in 1996. Participants with ovariectomy or hysterectomy were excluded, and the remaining participants were categorized into four groups: premenopausal (n= 38), perimenopausal (n= 14), postmenopausal group 1 (5 years or less since menopause; n= 18), and postmenopausal group 2 (6 years or more since menopause; n= 74). The mean value of total E2 was highest in the premenopausal group (49.1 pg/ml), followed by the perimenopausal group (26.4 pg/ml), and the postmenopausal groups (0.83 pg/ml in postmenopausal group 1 and 0.96 pg/ml in postmenopausal group 2). The means for UBE2 showed the same pattern across the groups. After the multiple regression analysis of BMD at follow-up and endogenous estrogens, in premenopausal women, there were no significant associations between BMD at follow-up and serum total E2 and UBE2. In perimenopausal women, however, serum total E2 and UBE2 were significantly correlated with trochanteric BMD at follow-up (P < 0.05); and in postmenopausal group 2, they were significantly correlated with lumbar spine and Ward's triangle BMD at follow-up (P < 0.001 at lumbar spine, P < 0.05 at Ward's triangle). Concerning the association between BMD at follow-up and SHBG, in the premenopausal group, serum levels of SHBG were negatively correlated with BMD at the femoral neck (P < 0.05). In regard to partial regression coefficients for the change rates of BMD over 3 years and serum estrogens and SHBG concentrations, in perimenopausal women, UBE2 was correlated with the change rate of BMD at Ward's triangle (P < 0.05), and in postmenopausal group 1, serum levels of SHBG were significantly negatively related to change in BMD at the trochanter (P < 0.01). No other relationships with change in BMD were observed at any sites. These findings suggest that serum E2, UBE2, and SHBG levels differentially predict BMD levels in groups of differing menstrual status. It would, however, be difficult to predict bone loss in middle-aged and elderly Japanese women over a 3-year period using these indices alone. Received: November 29, 2001 / Accepted: February 28, 2002  相似文献   
100.

Background and Aims

Endoscopic submucosal dissection (ESD) has recently been applied to the treatment of superficial colorectal cancer. Clinical outcomes compared with conventional endoscopic mucosal resection (EMR) have not been determined so our aim was to compare the effectiveness of ESD with conventional EMR for colorectal tumors ≥20 mm.

Methods

This was a retrospective case-controlled study performed at the National Cancer Center Hospital in Tokyo, Japan involving 373 colorectal tumors ≥20 mm determined histologically to be curative resections. Data acquisition was from a prospectively completed database. We evaluated histology, tumor size, procedure time, en bloc resection rate, recurrence rate, and associated complications for both the ESD and EMR groups.

Results

A total of 145 colorectal tumors were treated by ESD and another 228 were treated by EMR. ESD was associated with a longer procedure time (108 ± 71 min/29 ± 25 min; p < 0.0001), higher en bloc resection rate (84%/33%; p < 0.0001) and larger resected specimens (37 ± 14 mm/28 ± 8 mm; p = 0.0006), but involved a similar percentage of cancers (69%/66%; p = NS). There were three (2%) recurrences in the ESD group and 33 (14%) in the EMR group requiring additional EMR (p < 0.0001). The perforation rate was 6.2% (9) in the ESD group and 1.3% (3) in the EMR group (p = NS) with delayed bleeding occurring in 1.4% (2) and 3.1% (7) of the procedures (p = NS), respectively, as all complications were effectively treated endoscopically.

Conclusions

Despite its longer procedure time and higher perforation rate, ESD resulted in higher en bloc resection and curative rates compared with EMR and all ESD perforations were successfully managed by conservative endoscopic treatment.  相似文献   
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