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991.
The prognosis for patients with recurrent malignant glioma is poor. Both temozolomide and irinotecan have been shown to be active in this disease. A study was performed combining temozolomide 200 mg/m2 daily for 5 days and irinotecan 125 mg/m2 on days 6, 13, and 20 initially (Schedule A) and then changed to (Schedule B) temozolomide 200 mg/m2 daily for 5 days and irinotecan 350 mg/m2 on day 6. Each cycle was 28 days. All patients with recurrent tumor had to complete two cycles of therapy to be evaluable. Six cycles of treatment were provided for all responders. Thirty-two patients were treated, 6 with schedule A, 24 with schedule B, and 2 initially schedule A and then switched to schedule B. Eighteen patients (56%) had glioblastoma and 14 patients and anaplastic glioma (AOA 8, anaplastic astrocytoma 4, AO 2). Eighty-three percent (15/18) of patients with glioblastoma responded (complete response [CR] 2, partial response [PR] 3, stable disease [SD] 10). Median duration of response was 24 weeks, and 6-month progression-free survival (PFS) was 39% (7/18). Fourteen patients with anaplastic glioma were treated and all responded (CR 3, PR 2, SD 9). Median duration of response was 29 weeks and 6-month PFS was 71% (10/14). Grade IV leukopenia occurred in one patient and grade IV thrombocytopenia in two patients. Two patients were admitted to the hospital for neutropenic fever. Nonhematologic toxicity was mild and mostly gastrointestinal. These results demonstrate a favorable response and low toxicity with combined irinotecan and temozolomide therapy and warrant further clinical evaluation.  相似文献   
992.
DT-diaphorase: a target for new anticancer drugs   总被引:2,自引:0,他引:2  
DT-diaphorase (DTD) is an obligate two-electron reductase which bioactivates chemotherapeutic quinones. DTD levels are elevated in a number of tumour types, including non-small cell lung carcinoma, colorectal carcinoma, liver cancers and breast carcinomas, when compared to the surrounding normal tissue. The differential in DTD between tumour and normal tissue should allow targeted activation of chemotherapeutic quinones in the tumour whilst minimising normal tissue toxicity. The prototypical bioreductive drug is Mitomycin C (MMC) which is widely used in clinical practice. However, MMC is actually a relatively poor substrate for DTD and its metabolism is pH-dependent. Other bioreductive drugs have failed because of poor solubility and inability to surpass other agents in use. RH1, a novel diaziridinylbenzoquinone, is a more efficient substrate for DTD. It has been demonstrated to have anti-tumour effects both in vitro and in vivo and demonstrates a relationship between DTD expression levels and drug response. RH1 has recently entered a phase I clinical trial in solid tumours under the auspices of Cancer Research UK. Recent work has demonstrated that DTD is present in the nucleus and is associated with both p53 and the heat shock protein, HSP-70. Furthermore, DTD is inducible by several non-toxic compounds and therefore much interest has focussed on increasing the differential in DTD levels between tumour and normal tissues.  相似文献   
993.
PURPOSE: To assess the usefulness of hyperpolarized helium (3He) MRI, including apparent diffusion coefficient measurements, in the detection and evaluation of radiation-induced lung injury in rats. METHODS AND MATERIALS: Female Fischer-344 rats were treated to the right lung with fractionated dose of 40 Gy (5 x 8 Gy) using 4-MV photons. Conventional proton (1H) and hyperpolarized (3He) MRI were used to image the lungs 3-6 months after radiation treatment. Apparent diffusion coefficient (ADC) maps of hyperpolarized 3He in the lungs were calculated using a nonlinear, least-squares fitting routine on a pixel-by-pixel basis. After imaging, lungs were processed for histologic assessment of damage. RESULTS: The effect of radiation was time dependent with progressive right lung damage ranging from mild to moderate at 3 months to severe fibrosis with structural deformation at 6 months after radiation. There was a significant decrease in the apparent diffusion coefficient of hyperpolarized 3He gas in radiation-treated lungs. Areas of decreased ADC in the lungs correlated with fibrosis shown by histology. CONCLUSION: This is the first study to show that hyperpolarized 3He MRI can detect radiation-induced lung injury noninvasively. Reduced hyperpolarized 3He ADC values postradiation likely reflect reduced alveolar volumes associated with fibrosis of the interstitium. Future studies at earlier time points may determine whether this noninvasive imaging technique can detect lung damage before clinical symptoms. Development of this new approach of magnetic resonance lung imaging in the rat model of radiation-induced lung injury will increase the ability to develop appropriate algorithms and more accurate models of the normal tissue complication probability.  相似文献   
994.
995.
There is mounting evidence in support of a significant role for influenza infection in the development of atherosclerosis and the triggering of its complications. Here we review the biologic basis of this relationship, with special emphasis on the pro-inflammatory and pro-thrombotic effects of influenza infection. We also discuss the related epidemiologic findings and discuss in detail the possible causal relationship between influenza and cardiovascular disease. We appraise the relationship between influenza and coronary heart disease, on the basis of Bradford Hill's criteria of causality. We show that our proposed relationship meets the following criteria: strength of association, consistency, temporal sequence, coherence, biologic plausibility, experimental evidence, and analogy. Further studies are needed to assess whether it meets the criterion of biologic gradient. Specificity is not met, but meeting that criterion is of least importance in the study of multifactorial chronic diseases such as coronary heart disease. These criteria do not yield indisputable evidence for or against cause-and-effect, but they can help researchers appraise available evidence and determine the areas that need further research. The case for expanding the research on the effect of influenza on cardiovascular disease is a strong one, for most of Hill's criteria are met.  相似文献   
996.
997.
Our objective was the identification of children with scoliosis at higher risk of prolonged postoperative mechanical ventilation (MV) permits improved pre- and perioperative respiratory care to reduce postoperative complications. Pulmonary function testing (PFT) predicts prolonged postoperative MV in children who can reliably perform PFT, but some children cannot perform PFT. The objective of this study was to determine if polysomnography (PSG) or infant pulmonary function testing (IPFT) could predict prolonged postoperative MV (defined as MV >3 days) in children undergoing scoliosis surgery who could not reliably perform PFT. We studied 110 patients (age range, 10.8 +/- 4.9 [SD] years) who had preoperative PSG, and 18 patients (age range, 4.0 +/- 2.9 [SD] years) who had preoperative IPFT prior to undergoing any type of scoliosis repair by the Children's Hospital of Los Angeles Division of Orthopedic Surgery from January 1990- July 2001. The following information was reviewed and correlated: preoperative PSG parameters (baseline and nadir S(aO(2) ), baseline and peak P(ETCO(2) ), and apnea hypopnea index [AHI]), preoperative IPFT parameters (respiratory system compliance [C(rs)], respiratory system resistance [R(rs)], tidal volume [V(T)], and FRC), and length of postoperative MV. Twenty-seven patients (25%) who had PSG and 5 patients (28%) who had IPFT required postoperative MV >3 days. There was no association between baseline and nadir S(aO(2) ) 相似文献   
998.
999.
Médina M  Repérant J  Ward R  Miceli D 《Brain research》2004,1025(1-2):231-236
A small contingent of 30-50 of centrifugal visual fibres, showing FMRF-amide-like immunoreactivity, has been identified in C. niloticus; these fibres extend from the chiasmatic region into the retina. They do not take the marginal optic tract, but pass medially to the chiasmatic fascicles, from the preoptic region. The cells of origin of these fibres have not been identified. However, none of the retinopetal neurons of the brainstem [M. Medina, J. Reperant, R. Ward, D. Miceli, Centrifugal visual system of Crocodylus niloticus : a hodological, histochemical and immunocytochemical study, J. Comp. Neurol. 468 (2004) 65-85], labelled by retrograde transport of rhodamine beta-isothiocyanate after intraocular injection of this tracer, show FMRF-amide-like immunoreactivity; neither are any of the FMRF-amide-like immunopositive neurons in the crocodile brain, particularly those of the complex involving the terminal nerve and the septo-preoptic region, labelled by rhodamine after its intraocular injection.  相似文献   
1000.
Care provider assessment of intrathecal baclofen in children   总被引:2,自引:0,他引:2  
Intrathecal baclofen is used increasingly to manage severe spasticity in children. Before implanting the baclofen pump, care providers typically ask how it will benefit their child. The purpose of this study was to describe the perceptions of care providers about intrathecal baclofen for management of spasticity in 80 individuals (52 males, 28 females). The individuals were younger than 22 years at the time of implantation (mean age 11 years, SD 5 years; range 3 to 21 years). Participants had been implanted with the pump for a minimum of one year at the time of evaluation. The most common diagnoses were quadriplegic and diplegic cerebral palsy and traumatic brain injury. Most participants were at level IV and V on the Gross Motor Function Classification System. After pump implantation most participants had tone reduction on the Ashworth scale of 1 to 1.9 in the lower extremities and 0 to 0.9 in the upper extremities. Lower extremity range of motion was maintained in 43 of 51 individuals (84%) and lost in 8 participants (16%). Complications requiring surgery occurred in 63 of a larger group of 152 patients (incidence per patient-year of follow-up was 0.19). Thirty-one of the 80 children had orthopedic procedures after pump placement. Only one of these was unexpected and none had rapid progression of scoliosis. Most treatment goals were achieved. Goals most commonly chosen (decreased pain, prevention of worsening of deformity, and improved ease of care) were improved in 91%, 91%, and 88% of participants respectively. Ninety-five per cent of care providers agreed that they would have this procedure performed again (81% strongly agreed, 14% slightly agreed). All care providers reported improvement in scores on the Caregiver Questionnaire. This information has been helpful to families considering intrathecal baclofen therapy.  相似文献   
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