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71.
Lymphoblasts in bone marrow samples, obtained from 43 children with acute lymphoblastic leukemia at diagnosis, were incubated with 1.0 mumols/L [3H] methotrexate for 24 hours in vitro. Nonexchangeable methotrexate and methotrexate polyglutamates were separated and quantitated. Event-free survival at 5 years was 38% +/- 9% for all 43 patients (27 failures), and 44% +/- 10% for the 35 with non-T, non-B- cell acute lymphoblastic leukemia (20 failures). Of these 35 children, those whose lymphoblasts accumulated more than 100 pmol methotrexate and 500 pmol methotrexate polyglutamates per billion cells experienced better 5-year event-free survival than those whose lymphoblasts did not (65% +/- 12% v 22% +/- 9%, P = .010). This difference characterized "good-risk" patients who were female (P = .014), less than age 7 at diagnosis (P = .005), or had low initial white blood cell counts (less than 20 X 10(9)/L, P = .018). Findings were similar for the 43 children with acute lymphoblastic leukemia and for the "good-risk" children in this total group. Thus, the ability of lymphoblasts to accumulate methotrexate and form methotrexate polyglutamates may be important to the curative properties of current therapy of acute lymphoblastic leukemia in children, particularly for "good-risk" patients. In such patients, inherent rather than acquired drug resistance may be the initial event leading to treatment failure. 相似文献
72.
Bone marrow transplantation for patients with Philadelphia chromosome- positive acute lymphoblastic leukemia 总被引:1,自引:2,他引:1
Forman SJ; O'Donnell MR; Nademanee AP; Snyder DS; Bierman PJ; Schmidt GM; Fahey JL; Stein AS; Parker PM; Blume KG 《Blood》1987,70(2):587-588
We report the treatment outcome of allogeneic bone marrow transplantation in ten patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. Six patients are alive and well for 6 to 30 months (median 19 months) after transplantation. Four patients died with transplant related complications. In view of the poor prognosis associated with this disease, marrow ablation followed by allogeneic or syngeneic marrow grafting may be the preferred treatment modality if a suitable marrow donor is available. 相似文献
73.
Snyder DS; Negrin RS; O'Donnell MR; Chao NJ; Amylon MD; Long GD; Nademanee AP; Stein AS; Parker PM; Smith EP 《Blood》1994,84(5):1672-1679
Ninety-four consecutive patients with chronic myelogenous leukemia in first clinical chronic phase, median age of 34.0 years (range, 6.8 to 52.4 years), with a histocompatible sibling donor, were treated with fractionated total body irradiation (1,320 cGy) and high-dose etoposide (60 mg/kg) followed by allogeneic bone marrow transplantation (BMT). The median time from diagnosis to BMT was 7.0 months (range, 2.3 to 72.0 months). Sixty patients were treated before BMT with hydroxyurea alone, four patients with busulfan alone, one patient with interferon alone, and the other 29 patients were treated with various combinations of these drugs. Cumulative probabilities of overall survival, event- free survival, and relapse at 5 years were 73%, 64%, and 14%, respectively. The median follow-up time for surviving patients was 38 months, ranging from 12 to 88 months. By stepwise Cox regression analysis, significant prognostic variables were age at transplant, acute graft-versus-host disease > or = grade II, cytomegalovirus- associated interstitial pneumonitis, and years from diagnosis to BMT. 相似文献
74.
75.
DS Keller RN Tahilramani JR Flores-Gonzalez S. Ibarra EM Haas 《Surgical endoscopy》2016,30(6):2192-2198
Background
Our objective was to evaluate the impact of a novel multimodal pain management strategy on intraoperative opioid requirements, postoperative pain, narcotic use, and length of stay.Methods
Consecutive patients undergoing elective laparoscopic colorectal resection were managed with an experimental protocol. The protocol uses a post-induction, pre-incision bilateral TAP block and local peritoneal infiltration at port sites with long-acting liposomal bupivacaine (20 mL long-acting liposomal bupivacaine, 30 mL 0.25 % bupivacaine, 30 mL saline). Experimental patients were matched on age, body mass index, gender, comorbidity, diagnosis, and procedure to a control group that received no block or local wound infiltration. Both groups followed a standardized enhanced recovery pathway. Demographics, perioperative, and postoperative outcomes were evaluated. The main outcome measures were intraoperative opioids, postoperative pain, opioid use, and length of stay.Results
Fifty patients were analyzed—25 experimental and 25 controls. Patients were well matched on all demographics. In both cohorts, the main diagnosis was colorectal cancer and primary procedure performed a segmental resection. Operative times were similar (p = 0.41). Experimental patients received significantly less intraoperative fentanyl (mean 158 mcg experimental vs. 299 mcg control; p < 0.01). The experimental group had significantly lower initial (p < 0.01) and final PACU pain scores (p = 0.04) and shorter LOS (3.0 vs. 4.1 days, p = 0.04) compared to controls. Experimental patients trended toward shorter PACU times and lower opioid use and daily pain scores throughout the hospital stay. Postoperative complication and readmission rates were similar across groups. There were no reoperations or mortality.Conclusions
Our multimodal pain management strategy reduced intraoperative opioid administration. Postoperatively, improvements in PACU time, postoperative pain and narcotic use, and lengths of stay were seen in the experimental cohort. With the favorable finding from the pilot study, further investigation is warranted to fully evaluate the impact of this pain management protocol on patient satisfaction, clinical and financial outcomes.76.
77.
The influence of intracerebroventricular (ICV) vs intravenous (IV) administration of (D-Ala2, Met5) enkephalinamide (Dalamide) on normal and stimulated (cholera toxin) jejunal fluxes of water, Na+, and K+ were investigated in dogs prepared with a Thiry-Vella (TV) loop. Intestinal transport in the TV loop and concomitant transit time were measured during an infusion (2 ml/min) of an isotonic electrolyte solution alone, or containing 0.4 micrograms/ml of cholera toxin (CT). Basal net water absorption was slightly, but significantly (P less than 0.05), increased during an ICV infusion of Dalamide at 0.5 ng/kg/min, while the secretory effects of cholera toxin were markedly reduced by nearly 75%. Similar effects were observed for Na+ and K+ movement. In contrast, Dalamide infused intravenously at a five times higher dose, ie, 2.5 ng/kg/min did not affect the control and CT-stimulated water and electrolyte movements. The jejunal loop transit times were halved during CT infusion. Similar values were observed under Dalamide ICV administration as well as during a five times higher dose of Dalamide administered intravenously. It was concluded that (1) Dalamide administered into the CNS, but not peripherally, increased the absorption of water, Na+, and K+, causing a net reduction in their secretion induced by cholera toxin; and (2) these effects did not result from changes in transit time. These results also suggest that Met-enkephalin can act in the brain to affect the intestinal transport of water and electrolytes in dogs. 相似文献
78.
Roberts JL; Fishman EK; Hartman DS; Sanders R; Goodman Z; Siegelman SS 《Radiology》1986,158(3):613-617
Seven cases of lipomatous masses within the liver parenchyma were demonstrated with computed tomography (CT). Five of these cases were obtained from a retrospective review of 50 cases of renal angiomyolipoma in which the liver was adequately demonstrated. The other two cases were from the files of the Armed Forces Institute of Pathology and had no associated renal lesions. Three of the five cases were associated with tuberous sclerosis. In all seven cases, the fatty tumors appeared on CT scans as a well-defined, 0.8-13-cm mass, with attenuation coefficients of less than -30 HU. On ultrasound studies, the lesions were well circumscribed, highly echogenic, and similar to hemangiomas. While distinctly rare lesions, these lipomatous masses are not as unusual as the literature would indicate. One may anticipate such masses in patients with renal angiomyolipomas and in a relatively high percentage of those with tuberous sclerosis. 相似文献
79.
Integration of local inputs in visual cortex 总被引:1,自引:0,他引:1
In mammalian visual cortex, local connections are ubiquitous, extensively
linking adjacent neurons of all types. In this study, optical maps of
intrinsic signals and responses from single neurons were obtained from the
same region of cat visual cortex while the effectiveness of the local
cortical circuitry was altered by focally disinhibiting neurons within a
column of known orientation preference. Maps of intrinsic signals indicated
that local connections provide strong and functional subthreshold inputs to
neighboring columns of other orientation preferences, altering the observed
orientation preference to that of the disinhibited column. However,
measuring the suprathreshold response using single-cell recordings revealed
only mild changes of preferred orientation over the affected region.
Because strongly tuned subthreshold inputs from cortex only marginally
affect the tuning of a cortical cell's output, it is concluded that local
cortical inputs are integrated weakly compared to geniculate inputs. Such
circuitry potentially allows for the normalization of responses across a
wide range of input activity through local averaging.
相似文献
80.