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81.
Choroid plexus carcinoma was diagnosed in a 10-year-old maltese dog with chief complaint of progressive ataxia and head tilt. No abnormalities was observed on hemogram, radiographs of the skull, and electroencepharograph (EEG). Neurological examination suggested central vestibular lesions. On the magnetic resonance imaging (MRI) examination, images after contrast enhancement with Gadolinium DTPA-dimeglumine showed a rough circular lesion with an increased signal intensity in caudal fossa. This lesion was histopathologically confirmed to be choroid plexus carcinoma.  相似文献   
82.
Irinotecan hydrochloride (CPT-11) is a new derivative of camptothecin which inhibits topoisomerase I. Phase II studies have demonstrated that CPT-11 is active against a broad spectrum of neoplasms including intractable non-Hodgkin's lymphoma. An early phase II study in lymphoma suggested that a schedule of daily infusions of 40 mg/m2/day for three or five consecutive days is more effective than a single infusion of 200 mg/m2 every three to four weeks. Carboplatin is also an active agent against lymphoma, and preclinical studies have shown that CPT-11 and its active metabolite have a synergistic effect with platinum compounds. To evaluate the maximal tolerated dose (MTD) and the therapeutic efficacy of CPT-11 in combination with carboplatin in relapsed or refractory non-Hodgkin's lymphoma, we conducted a combination phase I/II study. The starting dose of CPT-11 was 20 mg/m2/day (days 1 through 3 and 8 through 10), and dose escalations of 5 mg/m2/day increments were planned, with a fixed dose of carboplatin (300 mg/m2, day 1). Six of the eight patients receiving both agents at the starting dose level developed critical toxicities such as grade 4 hematologic (neutropenia 6/8, thrombocytopenia 1/8) and grade 3 non-hematologic toxicities (diarrhea 2/8, transaminase elevation 1/8). Further dose escalation of CPT-11 was halted, and the starting doses were judged to be the MTDs. The response rate (25%, 2/8) to the combination of the MTDs was not superior to that of CPT-11 alone in a previous phase II study (38%, 26/69), and the MTD of CPT-11 in combination with carboplatin was less than half the single-agent dose. We conclude that carboplatin is not recommendable for combination with CPT-11 in lymphoma patients. Other suitable agents for such a combination should be sought.  相似文献   
83.
BACKGROUND: It has been reported that large amounts of nitric oxide (NO) are released in patients with sepsis. NO is converted to methemoglobin and nitrate. This study was designed to determine whether blood methemoglobin levels were increased in patients with sepsis or septic shock. METHODS: Forty-five critically ill patients including 8 with sepsis but without shock, 6 with septic shock and 31 non-septic patients were enrolled in the study. For septic and septic shock patients, blood methemoglobin concentrations were measured during sepsis or septic shock and at the time of recovery or just before the onset of sepsis. For the remaining non-septic patients, methemoglobin concentrations were measured at ICU admission and discharge. RESULTS: Blood methemoglobin levels in the presence of sepsis or septic shock were significantly (P < 0.05) higher than those in non-septic patients and those at recovery or just before the onset of sepsis in both septic and septic shock patients. CONCLUSIONS: Blood methemoglobin concentration may be useful as a marker of the onset of sepsis or septic shock.  相似文献   
84.
T cell activation involves specific interactions between the TCR and peptides presented by the MHC. This engagement leads to phosphorylation and subsequent internalization of the TCR complex. By analyzing the kinetics of the internalization of TCR, we found that the rate of TCR down-regulation was proportional to the square of the TCR density. Mathematical modeling of TCR interactions indicates that such a relation is only possible if TCR dimerize before internalization. By mathematical analysis, our data would also be compatible with trimer but not larger oligomer formation. Thus, minimal TCR oligomerization is an essential step for peptide-mediated T cell activation.  相似文献   
85.
A method of developing strategic CIM is described. Relationship between CIM and firm's competitive power is clarified, and a fundamental planning procedure for CIM is developed for enhancing the competitiveness. In the procedure, the system configuration of CIM is analyzed using 0–1 goal programming techniques. A numerical example is also demonstrated to show the effectiveness of the procedure.  相似文献   
86.
It has been suggested that tumor necrosis factor-alpha (TNF-alpha) is a key mediator of insulin resistance in non-insulin-dependent diabetes mellitus (NIDDM). TNF-alpha is synthesized as a membrane-bound precursor; this is proteolytically processed to an active form by a matrix metalloproteinase (MMP)-like enzyme. In this study, we have used KKAy mice which show insulin resistance like NIDDM to investigate the effects of KB-R7785, a novel MMP inhibitor, on blood glucose and insulin levels. Subcutaneous administration of KB-R7785 at 100 mg/kg twice daily (i.e., 200 mg/kg/day) for 4 weeks resulted in a significant decrease in plasma glucose levels which was observed after 3 weeks. Oral administration of pioglitazone (20 mg/kg twice daily or 40 mg/kg/day for 4 weeks), an agent known to ameliorate insulin sensitivity, significantly decreased plasma glucose levels during the treatment period. KB-R7785, but not pioglitazone, also significantly decreased plasma insulin levels. Lipopolysaccharide (LPS) increased plasma TNF-alpha levels to a significantly greater degree in KKAy mice than in normal C57BL mice; this was inhibitable in KKAy mice by KB-R7785. In contrast, pioglitazone did not affect the LPS-induced increase in plasma TNF-alpha levels in KKAy mice. These results suggest that KB-R7785 exerts its antidiabetic effect by ameliorating insulin sensitivity through the inhibition of TNF-alpha production.  相似文献   
87.
In this paper, two time relaxation parameters are introduce to a thermal lattice BGK, model to make its Prandtl number controllable. The dependency of the Prandtl number on the two parameters is derived. Numerical measurement of the transport coefficients is used to demonstrate the validity of the method. Furthermore, two examples of convective heat transfer are calculated, with one to show the effectiveness, and the other to show the breakdown of the two-parameter formulation under different conditions.  相似文献   
88.
A new silicone hollow fiber membrane oxygenator for extracorporeal membrane oxygenation (ECMO) was developed using an ultrathin silicone hollow fiber, with a 300 microm outer diameter and a wall thickness of 50 microm. The hollow fibers were mechanically cross-wound on the flow distributor to achieve equal distribution of blood flow without changing the fiber shape. The housing, made of silicone coated acryl, was 236 mm long with an inner diameter of 60 mm. The surface area was 1.0 m2 for prototype 211, and 1.1 m2 for prototype 209. The silicone fiber length was 150 mm, and the silicone membrane packing density was 43% for prototype 211 and 36% for prototype 209. Prototype 211 has a priming volume of 208 ml, and prototype 209 has a priming volume of 228 ml. The prototype 211 oxygenator demonstrates a gas transfer rate of 120 +/- 5 ml/min (mean +/- SD) for O2 and 67 +/- 12 ml/min for CO2 under 2 L of blood flow and 4 L of O2 gas flow. Prototype 209 produced the same values. The blood side pressure drop was low compared with the silicone sheet oxygenator (Avecor, 1500ECMO). These results showed that this new oxygenator for ECMO had efficiency similar to the silicone sheet oxygenator that has a 50% larger surface area. These results suggest that the new generation oxygenator using an ultrathin silicone hollow fiber possesses sufficient gas transfer performance for long-term extracorporeal lung support.  相似文献   
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