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81.
82.
Intensified 12-week CHOP (I-CHOP) plus G-CSF compared with standard 24-week CHOP (CHOP-21) for patients with intermediate-risk aggressive non-Hodgkin lymphoma: a phase 3 trial of the Dutch-Belgian Hemato-Oncology Cooperative Group (HOVON) 下载免费PDF全文
Verdonck LF Notenboom A de Jong DD MacKenzie MA Verhoef GE Kramer MH Ossenkoppele GJ Doorduijn JK Sonneveld P van Imhoff GW 《Blood》2007,109(7):2759-2766
Optimal dose and timing of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy for aggressive non-Hodgkin lymphoma (NHL) is still an unresolved issue. We assessed whether dose intensifications with cyclophosphamide and doxorubicin might improve outcome in younger patients with intermediate-risk aggressive NHL. Previously untreated patients were assigned to receive either 8 courses of standard CHOP (n = 239) or 6 courses of intensified (I)-CHOP (n = 238). Although there was a tendency in favor of I-CHOP for overall survival (OS), disease-free survival (DFS), and event-free survival (EFS), the differences were not significant. However, although these analyses were not planned, when the intermediate-risk group was divided into low-intermediate- and high-intermediate-risk patients according to the International Prognostic Index (IPI), low-intermediate-risk patients had improved 6-year OS (67% vs 52%; P = .05), DFS (58% vs 45%; P = .06), and EFS (41% vs 30%; P = .21) when they were treated with I-CHOP compared with standard CHOP. On the other hand, high-intermediate-risk patients seem to have no benefit from I-CHOP. Although clinically relevant side effects occurred more often in the I-CHOP arm, treatment-related mortality was similar. These data suggest that I-CHOP might be preferable to standard CHOP in younger patients with low-intermediate-risk aggressive NHL. 相似文献
83.
L. Lari A. Massi M. C. Fossi S. Casini C. Leonzio S. Focardi 《Archives of environmental contamination and toxicology》1994,26(2):234-239
Laboratory and field studies were conducted to evaluate the effects of the organophosphorus insecticide, azinphosmethyl, on bird populations and into the possibility of assessing toxic hazard by a non-destructive biomarker such as BChE inhibition. Japanese quail were treated with increasing doses of azinphos-methyl (0.5, 5, and 50 mg/kg) and sacrificed 7 and 24 h later. Serum BChE and CbE, brain AChE, and liver microsomal CbE activities showed different patterns of inhibition. The maximum inhibition of BChE and CbE usually occurred 7 h after treatment, whereas the effect on AChE was greater at 24 h. A positive correlation was found between BChE and AChE, 7 and 24 h after treatment. This correlation could serve as the foundation for a theoretical model for assessing toxic hazard through non-destructive biomarkers. The only effect on brain AChE was detected in the group treated with the highest concentrations of azinphos-methyl (50 mg/kg). Fugacity model calculations showed that such massive concentrations are very unlikely to occur under natural conditions after agricultural use of the compound.The non-destructive biomarker was used to test a population of tree sparrows living in a cherry orchard sprayed once with azinphos-methyl. No inhibition of BChE activity was found 24 h after application, and it was therefore concluded that the concentration of the insecticide used did not constitute a hazard for the birds. 相似文献
84.
OBJECTIVE: In patients with juvenile idiopathic arthritis (JIA) temporomandibular joint (TMJ) involvement is a common cause of severe growth disturbances. Extent of growth deviation depends on age of onset and duration of arthritis in the TMJ. TMJ arthritis is difficult to diagnose at an early stage since relatively few symptoms and clinical findings are related to this joint. The pathologic process can affect growth long before radiographic changes are seen. We investigated the relationship between TMJ arthritis and symptoms and clinical findings to suggest a clinical routine for diagnosing TMJ arthritis. We also describe the course of TMJ arthritis in relation to a commonly used radiographic method versus MRI. METHODS: Fifteen children with JIA were examined 4 times at 6 month intervals for TMJ involvement by clinical examination, MRI-scanning, and orthopantomograms (OPG). At baseline, 10 healthy children served as a control group. RESULTS: Patients reported more inability to chew and open their mouth than the control group. Translation of the condyle and range of mandibular movements were diminished in the arthritis group. Decreased translation was correlated to condylar changes seen on both OPG and MRI. MRI was superior to OPG in following changes of the condyle over time, and inflammation was detected in nearly all joints. CONCLUSION: OPG cannot be recommended for diagnosis or to follow the course of changes in the TMJ. We advocate recording condylar translation and mandibular range of motion as a current clinical routine to find early TMJ arthritis in contrast to the often used OPG performed in our study, which was an uncertain method. 相似文献
85.
Annelise Katrine Carrara Prieto João Eduardo Gomes-Filho Mariane Maffei Azuma Gustavo Sivieri-Araújo Luis Gustavo Narciso Jucilene Conceição Souza Paulo César Ciarlini Luciano Tavares Angelo Cintra 《Journal of endodontics》2017,43(10):1651-1656
Introduction
In this study, we investigated if apical periodontitis (AP) associated with diabetes influenced the levels of endogenous antioxidants, the total antioxidant capacity (TAC), and the oxidant parameter in the serum of Wistar rats.Methods
Forty male rats were divided into 4 equal groups: normal rats (N), rats with AP (AP), diabetic rats (D), and diabetic rats with AP (D + AP). Diabetes was induced by alloxan (150 mg/kg). AP was induced by exposing the pulpal tissue to the oral environment. After 36 days, blood and maxillae were collected. Albumin, bilirubin, uric acid, TAC, and malondialdehyde (MDA) levels were measured, and histologic analysis of the maxillae was performed. P < .05 was set as the threshold for statistical significance.Results
Uric acid levels were higher in the D + AP group when compared with that of the N, D, and AP groups (P < .05). The MDA concentration was higher in the D and D + AP groups when compared with the N and AP groups (P < .05). The level of albumin was lower in the D + AP group when compared with the N, AP, and D groups. Inflammatory infiltration was more intense in the periapical region in the D + AP group compared with that in the AP group (P < .05).Conclusions
Our findings indicate that diabetes may change the antioxidant status, increase the concentration of MDA and uric acid, and decrease albumin levels in the serum. In addition, AP can potentiate the effects of diabetes by reducing the levels of albumin and increasing the levels of uric acid. 相似文献86.
Felipe Vannucchi de Camargo Eduardo da Silva Fernandes Carla Schwengber ten Caten Annelise Kopp Alves Carlos Prez Bergmann Giangiacomo Minak 《Materials》2021,14(6)
The present study introduces the analysis of single-lap co-cured joints of thermoplastic self-reinforced composites made with reprocessed low-density polyethylene (LDPE) and reinforced by ultra-high-molecular-weight polyethylene (UHMWPE) fibers, along with a micromechanical analysis of its constituents. A set of optimal processing conditions for manufacturing these joints by hot-press is proposed through a design of experiment using the response surface method to maximize their in-plane shear strength by carrying tensile tests on co-cured tapes. Optimal processing conditions were found at 1 bar, 115 °C, and 300 s, yielding joints with 6.88 MPa of shear strength. The shear failure is generally preceded by multiple debonding-induced longitudinal cracks both inside and outside the joint due to accumulated transversal stress. This composite demonstrated to be an interesting structural material to be more widely applied in industry, possessing extremely elevated specific mechanical properties, progressive damage of co-cured joints (thus avoiding unannounced catastrophic failures) and ultimate recyclability. 相似文献
87.
Gianluca Plotino Nicola M. Grande Luca Testarelli Gianluca Gambarini Raffaella Castagnola Andrea Rossetti Taha Özyürek Massimo Cordaro Leonzio Fortunato 《Journal of endodontics》2018,44(10):1549-1552
Introduction
The aim of the present study was to investigate the impact of ambient temperature on the life span of nickel-titanium (NiTi) files.Methods
Cyclic fatigue testing of NiTi instruments was performed in a stainless steel artificial canal. During the experiment, 4 different temperatures (0°C, 20°C, 35°C, and 39°C) were used in a thermostatic bath controlled using electronic and infrared controls. Eighty R25 Reciproc Blue (VDW, Munich, Germany) and 80 R25 Reciproc (VDW) instruments were reciprocated in the artificial canal until fracture occurred, and the time to fracture and the length of the fractured fragment were recorded. The phase transformation temperature for 3 instruments of each type was analyzed by differential scanning calorimetry. One-way analysis of variance and Bonferroni tests were used to statistically analyze the data at a 5% significance level (P < .05).Results
Reciproc Blue instruments were significantly more resistant to cyclic fatigue than Reciproc at all the temperatures tested (P < .05). Fatigue resistance was proportionally higher as the environmental temperature decreased (0°C > 20°C > 35°C > 39°C). No signi?cant difference was registered for the length of the fractured fragment of both instruments tested at all temperatures tested (P > .05).Conclusions
Blue alloy significantly increases the cyclic fatigue resistance of Reciproc files compared with M-Wire alloy. Temperature significantly affects the life span of NiTi files. When the ambient temperature increases between 0°C and 35°C, the fatigue resistance of the files statistically decreases. 相似文献88.
89.
The efficiency of biomaterial-based gene delivery is determined by the interaction of the material and the vector. For lipoplexes, surface immobilization has been used to transfect cells for applications such as cell arrays and model tissue formation through patterned transfection. Further increases in the delivery efficiency are limited by cellular internalization, which may be overcome by altering the material/vector interactions. In this report, we investigated the modification of the lipoplex physical properties through self-assembly with cationic peptides, and subsequently quantified cellular association, internalization and nuclear accumulation of DNA and transfection. Relative to lipid alone, peptide-lipoplexes enhanced transfection by up to 4.6-fold. The presence of the peptide in the lipoplex increased internalization efficiency by up to 4.5-fold, decreased the percentage of lysosomal DNA by 2.1-fold and increased the efficiency of nuclear accumulation by 3.0-fold. In addition, an analysis of internalization pathways for peptide-lipoplexes indicated a greater role of clathrin and caveolae-mediated endocytosis relative to macropinocytosis, which was not observed for peptide-free lipoplexes. These results demonstrate peptide-induced enhancement of gene transfer by surface immobilization due to increased cellular internalization and nuclear accumulation, which has numerous applications ranging from cell-based assays to regenerative medicine. 相似文献
90.
Bjørndal K Krogdahl A Therkildsen MH Overgaard J Johansen J Kristensen CA Homøe P Sørensen CH Andersen E Bundgaard T Primdahl H Lambertsen K Andersen LJ Godballe C 《Oral oncology》2012,48(2):179-185
To describe outcome and prognostic factors in a national Danish series of patients treated for salivary gland carcinoma. From three Danish nation-wide registries and supplementary patient records, 871 patients diagnosed with primary major or minor salivary gland carcinoma in the period from 1990 to 2005 were identified. A total of 796 (91%) histological specimens were revised according to the WHO 2005 classification. The median follow-up time was 78 months. Three hundred and thirty-four patients (38%) experienced recurrence. Crude survival, disease-specific survival and recurrence-free survival after 5 and 10 years were 66%, 76%, 64% and 51%, 69%, 58%, respectively. In multivariate analysis age, latency, stage, microscopic margins, vascular invasion and histological grade were all independent prognostic factors with regards to crude and disease-specific survival. Stage, microscopic margins, vascular invasion and histological grade were independent prognostic factors for recurrence-free survival. Age over 61 years, latency under 8 months, stage 3+4 disease, involved or close microscopic margins, vascular invasion and high histological grade are all independent prognostic factors with a negative impact on survival in salivary gland carcinoma patients. This knowledge can be helpful in guiding clinicians in daily work and choice of treatment across the large variety of salivary gland carcinoma subtypes. 相似文献