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91.
In this study, the removal of acetic acid by supported liquid membrane (SLM) using hybrid polyethersulfone (PES)–graphene membrane prepared by vapor induced phase separation (VIPS) was investigated. The effects of graphene loading, coagulation bath temperature, air exposure time, and air humidity on the morphology, mechanical strength, porosity, and contact angle of the membrane were analyzed. The performance and stability of the hybrid membrane as a SLM support for acetic acid removal were studied. The best PES–graphene membrane support was produced at a coagulation bath temperature of 50 °C, an air exposure time of 30 s and air humidity of 80%. The fabricated membrane has a symmetrical micropore cellular structure, high porosity and high contact angle. Under specific SLM conditions, almost 95% of acetic acid was successfully removed from 10 g L−1 aqueous acetic acid solution. The hybrid membrane remains stable for more than 116 h without suffering any membrane breakage during the continuous SLM process.

In this study, the removal of acetic acid by supported liquid membrane (SLM) using hybrid polyethersulfone (PES)–graphene membrane prepared by vapor induced phase separation (VIPS) was investigated.  相似文献   
92.
The aim of the present study was to identify the effect of canavanine on the imidazoline receptor because canavanine is a guanidinium derivative that has a similar structure to imidazoline receptor ligands. Transfected Chinese hamster ovary‐K1 cells expressing imidazoline receptors (nischarin (NISCH)‐CHO‐K1 cells) were used to elucidate the direct effects of canavanine on imidazoline receptors. In addition, the imidazoline I3 receptor has been implicated in stimulation of insulin secretion from pancreatic β‐cells. Wistar rats were used to investigate the effects of canavanine (0.1, 1 and 2.5 mg/kg, i.v.) on insulin secretion. In addition the a specific I3 receptor antagonist KU14R (4 or 8 mg/kg, i.v.) was used to block I3 receptors. Canavanine decreased blood glucose by increasing plasma insulin in rats. In addition, canavanine increased calcium influx into NISCH‐CHO‐K1 cells in a manner similar to agmatine, the endogenous ligand of imidazoline receptors. Moreover, KU12R dose‐dependently attenuated canavanine‐induced insulin secretion in HIT‐T15 pancreatic β‐cells and in the plasma of rats. The data suggest that canavanine is an agonist of I3 receptors both in vivo and in vitro. Thus, canavanine would be a useful tool in imidazoline receptor research.  相似文献   
93.
The development of concise methods for the synthesis of small functionalised spirocyclic molecules is important in the search of new bioactive molecules. To contribute this, here we represent a diastereoselective oxa-hetero-Diels–Alder reaction for the synthesis of novel spiro indanone fused pyrano[3,2-c]chromene derivatives and studied their in vitro anticancer activities. Using previously less explored cyclic ketone i.e. indane-1,3-dione and 3-vinyl-2H-chromene derivatives, we obtained novel spiro-heterocyclic frameworks at the interphase between “drug-like” molecules and natural products. Various spiro indanone fused pyrano[3,2-c]chromene derivatives were synthesized regiospecifically bearing a quaternary stereocenter in high yields (up to 85%) with excellent diastereoselectivity in toluene using 4 Å MS as additive under reflux condition at 120 °C. In vitro cytotoxic studies of these compounds against MCF-7 (breast cancer), HCT-116 (colon cancer), H-357 (oral cancer), MD-MB-231(Breast cancer) cell lines were evaluated by MTT {3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide} assay in vitro. The screening results revealed that many of the compounds are showing moderate to high levels of anticancer activities against the tested cancer cell lines and some displayed potent inhibitory activities in comparison to the commercial anticancer drug 5-fluorouracil (5-FU). Among the series, compound 3′c showed most potent cytotoxicity (15.0–27.5 μM) in three cancer cell lines (MCF-7, HCT-116 and MD-MB-231).

Synthesis of novel spiro indanone fused pyrano[3,2-c]chromene derivatives following hetero-Diels–Alder reaction has been demonstrated and evaluated for their in vitro anticancer activity.  相似文献   
94.
Endometrial carcinoma occurs mostly in post-menopausal women. Classical methods of prognostication, as FIGO stage and histopathologic grade, could be improved by applying additional techniques, utilizing molecular biology and immunochemistry. p-53 tumor suppressor gene, the most commonly mutated gene in human cancers has been shown to play an important role in the biology of gynecologic carcinomas. Angiogenesis, a process of formation of new vessels, being connected to tumors progression and metastatic potential was shown to be linked with tumor suppressor genes expression. The aim of the study was to evaluate relationships between intensity of tumor angiogenesis, serum levels of Vascular Endothelial Growth Factor (VEGF) and tissue p-53 protein expression in endometrial adenocarcinoma. Angiogenic Point's Density (APD) was calculated in hot spots areas using the morphometric appliance. For detection of p53 protein in tumor samples, LSAB + Kit Alkaline Phosphatase (DAKO) was used. VEGF levels were assessed in patient's blood sampled before the operation. Overexpression of p53 protein was found in tumor tissue in 35.2% of cases and mean angiogenic points density was greater in p53 positive cases. Serum levels of VEGF were above the cut off level in 54.5% of patients, in those cases angiogenesis was also elevated. In cases of p53 overexpression, VEGF levels tended to be greater as compared with p53 negative cases. In conclusion, our study demonstrated that angiogenesis was more intensive in p53 positive cases, confirming the hypothesis of tumor suppressor-gene regulation of the process of neovascularization. Serum levels of VEGF were borderline-significantly higher in cases of p53 overexpression, they were also correlated to the angiogenesis. Joint assessment of angiogenesis and tumor suppressor genes expression may contribute to reliable evaluation of the biology of endometrial carcinoma.  相似文献   
95.
There have been disappointingly few effective treatment modalities for multiple liver metastases from pancreatic cancer. Percutaneous isolated hepatic perfusion, which was developed by us for delivering dose-intensive chemotherapy to the liver, has a high efficacy in the majority of patients with multiple primary and secondary liver tumors. We herein report the first experience of a two-stage treatment with extended local resection and subsequent two percutaneous isolated hepatic perfusions for advanced pancreatic ductal adenocarcinoma with liver metastases. The second percutaneous isolated hepatic perfusion with high-dose cisplatin and mitomycin G demonstrated a distinct regression of metastatic liver tumors. Although a long-term patient survival was not obtained due to local recurrence, liver metastases have been well controlled ever since. Given that further studies establish the efficacy of percutaneous isolated hepatic perfusion also in this field, this modality would be used as prophylaxis as well as treatment of liver metastasis in patients with advanced pancreatic ductal adenocarcinoma.  相似文献   
96.

Background

Botulinum toxin injected into the internal anal sphincter is used in the treatment of chronic anal fissure but there is no standardised technique for its administration. This randomised single centre trial compares bilateral (either side of fissure) to unilateral injection.

Methods

Participants were randomised to receive bilateral (50?+?50 units) or unilateral (100 units) Dysport® injections into the internal anal sphincter in an outpatient setting. Injection-related pain assessed by visual analogue scale was the primary outcome measure. Secondary outcomes were healing rate, fissure pain, incontinence, and global health scores.

Results

Between October 2008 and April 2012, 100 patients with chronic anal fissure were randomised to receive bilateral or unilateral injections. Injection-related pain was comparable in both groups. There was no difference in healing rate. Initially, there was greater improvement in fissure pain in the bilateral group but at 1 year the unilateral group showed greater improvement. Cleveland Clinic Incontinence score was lower in the unilateral group in the early post-treatment period and global health assessment (EuroQol EQ-VAS) was higher in the unilateral group at 1 year.

Conclusions

Injection-related pain was similar in bilateral and unilateral injection groups. Unilateral injection was as effective as bilateral injections in healing and improving fissure pain without any deterioration in continence.
  相似文献   
97.
ObjectivesTo compare the dental and skeletal treatment effects after total arch distalization using modified C-palatal plates (MCPPs) on adolescent patients with hypo- and hyperdivergent Class II malocclusion.Materials and MethodsThe study group included 40 patients with Class II malocclusion (18 boys and 22 girls, mean age = 12.2 ± 1.4 years) treated with MCPPs. Fixed orthodontic treatment started with the distalizing process in both groups. Participants were divided into hypo- or hyperdivergent groups based on their pretreatment Frankfort mandibular plane angle (FMA) ≤22° or ≥28°, respectively. Pre- and posttreatment lateral cephalograms were digitized, and 23 variables were measured and compared for both groups using paired and independent t-tests.ResultsThe hyper- and hypodivergent groups showed 2.7 mm and 4.3 mm of first molar crown distalizing movement, respectively (P < .001). The hypodivergent group had a slight 2.2° crown distal tipping of first molars compared with 0.3° in the hyperdivergent group. After distalization, the FMA increased 3.1° and 0.3°, in the hypodivergent and hyperdivergent groups, respectively (P < .001). SNA decreased in the hypodivergent group, while other skeletal variables presented no statistically significant differences in the changes between the groups.ConclusionsThe hypodivergent group showed more distal and tipping movement of the maxillary first molar and increased FMA than the hyperdivergent group. Therefore, clinicians must consider vertical facial types when distalizing molars using MCPPs in Class II nonextraction treatment.  相似文献   
98.
目的构建基于信息化平台的糖尿病患者自我管理质量评价指标体系,为开展依托信息化平台的糖尿病管理提供借鉴。方法2018年8—11月,在文献回顾和专家会议法的基础上拟定指标体系初稿,通过德尔菲法对28名从事糖尿病诊疗、糖尿病护理、慢病管理、护理管理、护理教育等方面的专家进行2轮函询并构建最终指标体系。计算专家的积极性、权威性,专家意见的一致性、协调性。结果2轮专家函询问卷的有效回收率分别为93.33%和100.00%,专家权威系数分别为0.911和0.945。第2轮专家函询中,一、二、三级指标的肯德尔协调系数分别为0.478、0.478和0.537(P<0.01),变异系数均<0.25。最终构建的基于信息化平台的糖尿病患者自我管理质量评价指标体系包含3项一级指标、9项二级指标和69项三级指标。结论基于信息化平台的糖尿病患者自我管理质量评价指标构建过程严谨科学,指标内容比较合理、可靠性好,可为完善以信息化平台为支撑的糖尿病患者自我管理干预内容、提升糖尿病综合管理质量提供一定参考。  相似文献   
99.

PURPOSE

Intrahepatic portal vein injuries secondary to blunt abdominal trauma are difficult to diagnose and can result in insidious bleeding. We aimed to compare computed tomography arterial portography (CTAP), reperfusion CTAP (rCTAP), and conventional computed tomography (CT) for diagnosing portal vein injuries after blunt hepatic trauma.

METHODS

Patients with blunt hepatic trauma, who were eligible for nonoperative management, underwent CTAP, rCTAP, and CT. The number and size of perfusion defects observed using the three methods were compared.

RESULTS

A total of 13 patients (seven males/six females) with a mean age of 34.5±14.1 years were included in the study. A total of 36 hepatic segments had perfusion defects on rCTAP and CT, while there were 47 hepatic segments with perfusion defects on CTAP. The size of perfusion defects on CT (239 cm3; interquartile range [IQR]: 129.5, 309.5) and rCTAP (238 cm3; IQR: 129.5, 310.5) were significantly smaller compared with CTAP (291 cm3; IQR: 136, 371) (both, P = 0.002).

CONCLUSION

Perfusion defects measured by CTAP were significantly greater than those determined by either rCTAP or CT in cases of blunt hepatic trauma. This finding suggests that CTAP is superior to rCTAP and CT in evaluating portal vein injuries after blunt liver trauma.The liver is one of the most frequently injured solid abdominal organs in the setting of blunt abdominal trauma (1). Fortunately, most patients with blunt hepatic trauma have relatively stable vital signs and need only supportive treatment or transarterial embolization (TAE) (19). Only 15% of patients, who present with hemodynamic instability or fail with nonoperative management, require operative intervention to manage their liver injury.Embolic therapy has been shown to have a high success rate in hemodynamically stable patients with blunt hepatic injury. TAE is associated with decreased abdominal infections, decreased transfusions, and decreased length of hospital stay compared with operative management (2, 3, 7). However, angiography can only detect bleeding from the hepatic artery; it cannot locate bleeding from the hepatic or portal vein. In the literature, portal vein injuries are not commonly described and most are the result of penetrating injuries to the extrahepatic portal veins. Mortality after a portal vein injury due to trauma is primarily due to hypovolemic shock and can be as high as 50% or greater (10, 11).Since the intrahepatic portions of the hepatic and portal veins are low pressure systems, they can bleed insidiously. Nevertheless, this subtle bleeding may require multiple transfusions and result in a prolonged hospital stay. Relative to an extrahepatic portal vein injury, patients with an intrahepatic portal vein injury may have relatively stable vital signs and slowly decreasing hemoglobin levels (10, 11). In addition, traumatic occlusion and/or thrombosis of the portal vein may cause large hepatic parenchymal infarction.Computed tomography arterial portography (CTAP) is a useful method based on portal enhancement of the liver by infusion of contrast material through the superior mesenteric artery for evaluating the portal venous system (1215) and is widely used in patients with hepatic tumors with portal venous invasion (13, 16, 17). CTAP has a high sensitivity and specificity in the evaluation of portal vein thrombosis due to tumor (90% sensitivity, 99% specificity, 95% positive predictive value, 97% negative predictive value) (14). However, few studies have focused specifically on the utility of CTAP in the evaluation of portal vein injury as a result of trauma.The liver has a dual blood supply and receives between 66% and 75% of its blood supply from the hepatic portal vein with the remainder supplied by the hepatic artery (18). CTAP reflects only portal venous perfusion while reperfusion CTAP (rCTAP) reflects hepatic arterial reperfusion. Both rCTAP and conventional computed tomography (CT) are useful for determining certain liver injuries. However, they do not specifically evaluate the portal vein.The purpose of this study was to compare CTAP, rCTAP, and CT for diagnosing portal vein injuries after blunt hepatic trauma. We hypothesized that CTAP would be superior to rCTAP and CT in assessing portal vein injury after blunt hepatic trauma.  相似文献   
100.
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