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41.
PURPOSE: An interval of six to eight weeks between completion of preoperative chemoradiation therapy and surgical resection of advanced rectal cancer has been described. Our purpose was to determine whether a longer time interval between completion of therapy and resection increases tumor downstaging and affects perioperative morbidity. METHODS: Forty patients with advanced adenocarcinoma of the rectum underwent preoperative chemoradiation on a prospective trial with irinotecan (50 mg/m2), 5-fluorouracil (225 mg/m2), and concomitant external-beam radiation (45-54 Gy) followed by complete surgical resection of the tumor with total mesorectal excision. The time interval between completion of chemoradiation and surgical resection ranged from 28 to 97 days. The patients were divided into two groups with 33 eligible patients: Group A (4-week to 8-week time interval; 28-56 days) and Group B (10-week to 14-week interval; 67-97 days). Tumor downstaging was compared between these two groups. The number of patients downstaged by at least one T stage, those downstaged by at least one N stage, those with pathologic complete responses, and those with only residual microscopic tumor foci were compared. Postoperative length of stay, estimated blood loss, perioperative morbidity, and sphincter-sparing procedures were also compared. Chi-squared tests and Student's t-test were calculated. RESULTS: Group A had 19 patients, and Group B had 14 patients. Patient demographics were comparable. Mean age was 52 years, and 70 percent of patients were male. There were no deaths. There were no statistical differences in perioperative morbidity, with three anastomotic leaks in Group A. Tumors were downstaged in 58 percent of patients in Group A and 43 percent of those in Group B (P = 0.61). Nodal downstaging occurred in 78 percent of Group A and 67 percent of Group B (P = 0.9). The pathologic complete response rate was 21 percent in Group A and 14 percent in Group B (P = 0.97), and a residual microfocus of tumor was found in 33 percent of patients in Group A and 42 percent of those in Group B (P = 0.90). These differences were not statistically significant. CONCLUSIONS: Perioperative morbidity is not affected by longer intervals. A longer interval between completion of neoadjuvant chemoradiation and surgical resection may not increase the tumor response rate of advanced rectal cancer in this cohort.  相似文献   
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A 51-year-old man with a history of stage IV angioimmunoblastic T-cell lymphoma was diagnosed with osteomyelitis of the patella. Legionella anisa was identified by 16S rRNA gene sequencing and culture. The patient had pneumonia 2 months prior to this osteomyelitis episode. L. anisa was retrospectively detected in his lung tissue by 16S rRNA gene sequencing and was considered the source of the L. anisa that caused his patella osteomyelitis.  相似文献   
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P25 comprising of mixed anatase and rutile phases is known to be highly photocatalytically active compared to the individual phases. Using a facile wet chemical method, we demonstrate a ternary nanocomposite consisting of Ni and Ag nanoparticles, decorated on the surface of XTiO2 (X: P25, rutile (R)) as an efficient visible-light-driven photocatalyst. Contrary to the current perspective, RTiO2-based Ni–Ag–RTiO2 shows the highest activity with the H2 evolution rate of ∼86 μmol g−1 W−1 h−1@535 nm. Together with quantitative assessment of active Ni, Ag and XTiO2 in these ternary systems using high energy synchrotron X-ray diffraction, transmission electron microscopy coupled energy dispersive spectroscopy mapping evidences the metal to semiconductor contact via Ag. The robust photocatalytic activity is attributed to the improved visible light absorption, as noted by the observed band edge of ∼2.67 eV corroborating well with the occurrence of Ti3+ in Ti 2p XPS. The effective charge separation due to intimate contact between Ni and RTiO2via Ag is further evidenced by the plasmon loss peak in Ag 3d XPS. Moreover, density functional theory calculations revealed enhanced adsorption of H2 on Ti8O16 clusters when both Ag and Ni are simultaneously present, owing to the hybridization of the metal atoms with d orbitals of Ti and p orbitals of O leading to enhanced bonding characteristics, as substantiated by the density of states. Additionally, the variation in the electronegativity in Bader charge analysis indicates the possibility of hydrogen evolution at the Ni sites, in agreement with the experimental observations.

Robust photocatalytic activity of Ni–Ag–RTiO2 is attributed to the improved visible light absorption and effective charge separation due to intimate contact between Ni and RTiO2via Ag, as evidenced by Ti3+ in Ti 2p XPS and energy dispersive mapping.  相似文献   
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Objectives

This study was conducted to determine the incidence of early stasis in radioembolization using resin yttrium-90 (Y-90) microspheres, to evaluate potential contributing factors, and to review initial imaging outcomes.

Methods

Patients in whom early stasis occurred were compared with those in whom complete delivery was achieved for tumour type and vascularity, tumour : normal liver ratio (T : N ratio) at technetium-99m-macroaggregated albumin (Tc-99m-MAA) angiography, previous intra-arterial therapy, and infusion site (left, right or whole liver). Tumour response was evaluated at 3 months and defined according to whether a partial response and stable disease versus progressive disease were demonstrated.

Results

A total of 71 patients underwent 128 Y-90 infusions in which 26 (20.3%) stasis events occurred. Hypervascular and hypovascular tumours had similar rates of stasis (17.4% versus 27.8%; P = NS). The mean ± standard deviation T : N ratio was 3.03 ± 1.54 and 3.66 ± 2.79 in patients with and without stasis, respectively (P = NS). Stasis occurred in 14 of 81 (17.3%) and 12 of 47 (25.5%) infusions following previous intra-arterial therapy and in therapy-naïve territories, respectively (P = NS). Early stasis occurred in 15 of 41 (36.6%) left, 10 of 65 (15.4%) right and one of 22 (4.5%) whole liver infusions (P < 0.001). Rates of partial response and stable disease were similar in the stasis (88.3%) and non-stasis (76.0%) groups (P = NS).

Conclusions

Early stasis occurred in approximately 20% of infusions with similar incidences in hyper-and hypovascular tumours. Whole-liver therapy reduced the incidence of stasis. Stasis did not appear to affect initial imaging outcomes.  相似文献   
46.
2,3-Diaminomaleonitrile (DAMN) has proved to be a valuable organic π-conjugated molecule having many applications in the area of chemosensors for sensing of ionic and neutral species because of its ability to act as a building block for well-defined molecular architectures and scaffolds for preorganised arrays of functionality. In this article, we discussed the utilization of 2,3-diaminomaleonitrile (DAMN) for the design and development of chemosensor molecules and their application in the area of metal ion, anion and reactive oxygen species sensing. Along with these, we present different examples of DAMN based chemosensors for multiple ion sensing. We also discuss the ion sensing mechanism and potential uses in other related areas of research.

2,3-Diamniomaleonitrile (DAMN) is valuable π-conjugated organic scaffold molecule for designing of efficient chemosensors for sensing of ionic and Reactive Oxygen Species (ROS).  相似文献   
47.
Objective:To evaluate the antidiabetic and antioxidant potential of Emblica officinalis(E.officinalis)fruit on normal and type 2 diabetic rats.Methods:Type 2 diabetes was induced into the male Long-Evans rats.The rats were divided into nine groups including control groups receiving water,type 2 diabetic controls,type 2 diabetic rats treated with glibenclamide(T2GT)and type 2diabetic rats treated with aqueous extract of fruit pulp of E.officinalis.They were fed orally for8 weeks with a single feeding.Blood was collected by cutting the tail tip on 0 and 28 days and by decapitation on 56 day.Packed red blood cells and serum were used for evaluating different biochemical parameters.Results:Four weeks administration of aqueous extract of E.officinalis improved oral glucose tolerance in type 2 rats and after 8 weeks it caused significant(P0.007)reduction in fasting serum glucose level compared to 0 day.Triglycerides decreased by 14%but there was no significant change in serum ALT,creatinine,cholesterol and insulin level in any group.Furthermore,reduced erythrocyte malondialdehyde level showed no significant change(P0.07)but reduced glutathione content was found to be increased significantly(P0.05).Conclusions:The aqueous extract of E.officinalis has a promising antidiabetic and antioxidant properties and may be considered for further clinical studies in drug development.  相似文献   
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