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191.
MK Bolla GJ Miller DM Yellon A Evans G Luc JP Cambou D Arveiler F Cambien DS Latchman SE Humphries IN Day 《Canadian Metallurgical Quarterly》1998,13(4):227-235
In 12 depressed inpatients referred for bilateral electroconvulsive therapy (ECT), each patient was titrated at the first treatment session by using an ascending method-of-limits procedure with a step-wise increase in pulse frequency (frequency titration) or train duration (duration titration). At the second treatment session, seizure threshold was redetermined by using the method (frequency or duration titration) not used at the first treatment. Frequency or duration was maintained at the lowest level when the other parameter was titrated. Seizure threshold was significantly lower with duration titration (mean, 90 mC; SD, 27.3) than frequency titration (mean, 114 mC; SD, 35.6; p = 0.03). On average, patients in the duration-titration group required 1.2 (SD, 0.6) subconvulsive stimulations before a seizure was elicited, and patients in the frequency-titration group required 1.7 (SD, 0.9) subconvulsive stimulations before a seizure was elicited, a nonsignificant difference. These findings suggest that to elicit a seizure during ECT, increasing train duration may be slightly more efficient than increasing frequency. Basic and other clinical research findings indicate that increasing pulse width may be an inefficient way to elicit a seizure. Therefore the following sequence in the determination of seizure threshold is worth considering when using dose-titration or related techniques: the train duration should be increased first before increasing pulse frequency, and the decision to increase pulse width should be reserved for patients who do not seize at the maximal duration and frequency settings. Further empiric research is needed to establish the utility of this approach. 相似文献
192.
TR Henry HA Buchtel RA Koeppe PB Pennell KJ Kluin S Minoshima 《Canadian Metallurgical Quarterly》1998,50(3):787-790
Patients with left temporal lobe epilepsy (TLE) often have impaired naming. We studied 13 patients with left TLE and 10 healthy control subjects with [(15)O]H2O PET during visual confrontation naming. Statistical mapping detected multiple regions of significant cerebral blood flow increases within individuals. The left fusiform gyrus was activated in nine healthy subjects, but only in two patients with TLE (a significant difference, p < 0.001). Other activation sites were more variable in healthy subjects and those with TLE. Impaired naming ability may be associated with a lack of increased cerebral blood flow in the left fusiform gyrus in TLE. 相似文献
193.
PW Pisters JL Abbruzzese NA Janjan KR Cleary C Charnsangavej MS Goswitz TA Rich I Raijman RA Wolff R Lenzi JE Lee DB Evans 《Canadian Metallurgical Quarterly》1998,16(12):3843-3850
PURPOSE: To evaluate the toxicities, radiographic and pathologic responses, and event-free outcomes with combined modality treatment that involves preoperative rapid-fractionation chemoradiation, pancreaticoduodenectomy, and electron-beam intraoperative radiation therapy (EB-IORT) for patients with resectable pancreatic adenocarcinoma. PATIENTS AND METHODS: Patients with radiographically resectable localized adenocarcinoma of the pancreatic head were entered onto a preoperative protocol that consisted of a 2-week course of fluorouracil (5-FU) 300 mg/m2 daily 5 days per week and concomitant rapid-fractionation radiation 30 Gy, 3 Gy daily 5 days per week. Radiographic restaging was performed 4 weeks after chemoradiation, and patients with localized disease underwent pancreaticoduodenectomy with EB-IORT 10 to 15 Gy. RESULTS: Thirty-five patients were entered onto the study and completed chemoradiation, 34 (97%) as outpatients. Three patients (9%) experienced grade 3 nausea and vomiting; no other grade 3 or 4 toxicities were observed. Of the 27 patients taken to surgery, 20 patients (74%) underwent pancreaticoduodenectomy with EB-IORT. All patients had a less than grade III pathologic response to preoperative chemoradiation. At a median follow-up of 37 months, the 3-year survival rate in patients who underwent combined modality therapy was 23%. CONCLUSION: Combined modality treatment with preoperative rapid-fractionation chemoradiation, pancreaticoduodenectomy, and EB-IORT is associated with minimal toxicity and excellent locoregional control. This represents one approach to maximize the proportion of patients who receive all components of combined modality therapy and avoids the toxicity of pancreaticoduodenectomy in patients found to have metastatic disease at the time of restaging. 相似文献
194.
SL Goldberg TR Klumpp AJ Magdalinski KF Mangan 《Canadian Metallurgical Quarterly》1998,16(12):3796-3802
PURPOSE: To determine the value of pretransplant studies in predicting day 100 nonrelapse toxic mortality following high-dose therapy. PATIENTS AND METHODS: A retrospective review of 383 consecutive hematopoietic stem-cell transplants was performed with attention to toxic mortality and pretransplant factors. Univariate log-rank analysis was used to yield the most significant cut-off values for individual factors. Multivariate analysis using Cox proportional hazards regression determined factors independently predictive of early toxic death. RESULTS: Nonrelapse toxic mortality before day 100 occurred in 23 of 383 (6.0%) transplant recipients. Factors associated with an increased risk of toxic death by univariate analysis included forced expiratory volume in 1 second (FEV1) less than 78% of predicted (P = .0002), allogeneic versus autologous transplant (P = .0003), diffusion capacity of carbon monoxide less than 52% of predicted (P = .002), serum creatinine concentration greater than 1.1 mg/dL (P = .003), Eastern Cooperative Oncology Group performance status greater than 0 (P = .006), preparative regimen containing total-body irradiation versus chemotherapy alone (P = .006), marrow versus blood stem cell (P = .01), serum ALT greater than 50 IU/L (P = .02), diagnosis of hematologic disorder versus solid tumor (P = .06), serum bilirubin level greater than 1.1 mg/dL (P = .08), left ventricular ejection fraction (P = .09), and growth factor use (P = .09). In the multivariate model, transplant type (relative risk, 4.2), FEV1 (relative risk, 4.5), performance status (relative risk, 3.7), serum creatinine (relative risk, 3.8), and serum bilirubin (relative risk, 3.7) were found to be independent predictors of early toxic mortality. CONCLUSION: The pretransplant evaluation is a useful tool to identify patients at risk for early toxic mortality following high-dose therapy. 相似文献
195.
M Tanaka TR Cummins K Ishikawa SD Dib-Hajj JA Black SG Waxman 《Canadian Metallurgical Quarterly》1998,9(6):967-972
In contrast to conventional T cells, natural killer (NK) 1.1+ T cell receptor (TCR)-alpha/beta+ (NK1+T) cells, NK cells, and intestinal intraepithelial lymphocytes (IELs) bearing CD8-alpha/alpha chains constitutively express the interleukin (IL)-2 receptor (R)beta/15Rbeta chain. Recent studies have indicated that IL-2Rbeta/15Rbeta chain is required for the development of these lymphocyte subsets, outlining the importance of IL-15. In this study, we investigated the development of these lymphocyte subsets in interferon regulatory factor 1-deficient (IRF-1-/-) mice. Surprisingly, all of these lymphocyte subsets were severely reduced in IRF-1-/- mice. Within CD8-alpha/alpha+ intestinal IEL subset, TCR-gamma/delta+ cells and TCR-alpha/beta+ cells were equally affected by IRF gene disruption. In contrast to intestinal TCR-gamma/delta+ cells, thymic TCR-gamma/delta+ cells developed normally in IRF-1-/- mice. Northern blot analysis further revealed that the induction of IL-15 messenger RNA was impaired in IRF-1-/- bone marrow cells, and the recovery of these lymphocyte subsets was observed when IRF-1-/- cells were cultured with IL-15 in vitro. These data indicate that IRF-1 regulates IL-15 gene expression, which may control the development of NK1+T cells, NK cells, and CD8-alpha/alpha+ IELs. 相似文献
196.
TR Kramer MB Powell MM Wilson J Salvatore HE Grossniklaus 《Canadian Metallurgical Quarterly》1998,82(8):953-960
Lectins are sensitive probes which bind carbohydrate structures specifically. In this study, we modified the lectin staining procedure for sensitive detection of carbohydrate structures in formalin-fixed, paraffin-embedded sections of normal and heterologous serum-induced fibrotic livers. The liver sections were heated in hot distilled water at 100 degrees C for 10 min (thermo-treatment: TT), and then stained with 24 different lectins. In comparison with the results from sections without TT (nonTT), enhanced and/or alternated staining patterns of 19 lectins were demonstrated in sections with TT, and enhanced staining of Vicia villosa agglutinin seen in Kupffer cells was noted. Interestingly, no positive staining was seen with Dolichos biflorus agglutinin, peanut agglutinin or soybean agglutinin (SBA), which recognize O-linked carbohydrate chains, in Kupffer cells of non-TT sections, but strong positive staining was demonstrated in those of TT sections. SBA-positive staining in the cytoplasm of some scattered hepatocytes located in the periportal and perifibrous zones and central zone of pseudolobules was demonstrated only in the fibrotic liver sections with TT. Such findings indicate the heterogeneity of hepatocytes in the liver with fibrosis. Formalin fixation causes masking of lectin binding sites, especially O-linked carbohydrate chains, and TT may recover such masking reactions. TT improved the staining reactions for many lectins in formalin-fixed, paraffin-embedded liver sections, and new staining patterns appear after TT. Modified TT staining procedures may be useful for the diagnosis and prognosis of liver fibrosis. 相似文献
197.
198.
NJ Beauchamp RN Pike M Daly L Butler M Makris TR Dafforn A Zhou HL Fitton FE Preston IR Peake RW Carrell 《Canadian Metallurgical Quarterly》1998,92(8):2696-2706
The inherent variability of conformational diseases is demonstrated by two families with different mutations of the same conserved aminoacid in antithrombin. Threonine 85 underlies the opening of the main beta-sheet of the molecule and its replacement, by the polar lysine, in antithrombin Wobble, resulted in a plasma deficiency of antithrombin with an uncharacteristically severe onset of thrombosis at 10 years of age, whereas the replacement of the same residue by a nonpolar methionine, antithrombin Wibble, gave near-normal levels of plasma antithrombin and more typical adult thromboembolic disease. Isolated antithrombin Wibble had a decreased thermal stability (Tm 56.2, normal 57.6 degreesC) but was fully stabilized by the heparin pentasaccharide (Tm 71.8, normal 71.0 degreesC), indicating that the prime abnormality is a laxity in the transition of the main sheet of the molecule from the 5- to 6-stranded form, as was confirmed by the ready conversion of antithrombin Wibble to the 6-stranded latent form on incubation. That this transition can occur in vivo was shown by the finding of nearly 10% of the proband's plasma antithrombin in the latent form and also, surprisingly, of small but definitive amounts of latent antithrombin in normal plasma. The latent transition will be predictably accelerated not only by gross mutations, as with antithrombin Wobble, to give severe episodic thrombosis, but also by milder mutations, as with antithrombin Wibble, to trigger thrombosis in the presence of other predisposing factors, including the conformational stress imposed by the raised body temperatures of fevers. Both antithrombin variants had an exceptional (25-fold) increase in heparin affinity and this, together with an increased inhibitory activity against factor Xa, provides evidence of the direct linkage of A-sheet opening to the conformational basis of heparin binding and activation. 相似文献
199.
A cephalometric study was conducted on 50 male and 54 female Sotho-Tswana children 11-16 years of age. The subjects were selected for excellence of occlusion and balance of facial proportions. Various analyses, including Steiner, Wits, and McNamara, were used for the evaluations. The mean measurements were compared with those of other Southern African Black groups and Caucasoids. Our study shows that cephalometric analyses for other groups cannot be used with confidence for the Sotho-Tswana people and our data provides norms for them. 相似文献
200.