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991.
CB Huckell 《Canadian Metallurgical Quarterly》1998,29(4):787-799
The advent of sterile technique, modern anesthesia, and organized industrial society have allowed for great advances and widespread use of cervical arthrodesis for a variety of disorders. This article defines expected outcome for cervical arthrodesis used to treat degenerative disease, trauma, deformity, and a variety of other disorders. 相似文献
992.
R Grün PH Huang W Huang F McDermott A Thorne CB Stringer G Yan 《Canadian Metallurgical Quarterly》1998,34(6):555-564
Male substance abuse patients with posttraumatic stress disorder (PTSD) (SA-PTSD; N = 140) were compared to patients with only substance use disorders (SA-only; N = 1,262), and those with other Axis I diagnoses (SA-PSY; N = 228) on changes during substance abuse treatment. Diagnoses were determined by chart review, and patients completed questionnaires assessing coping, cognitions, and psychological distress. Although SA-PTSD patients improved on outcomes during treatment, they showed less benefit relative to SA-only patients. At discharge, SA-PTSD patients reported less use of effective coping styles, and endorsed more positive beliefs about substance use than SA-only patients. They had more psychological distress than SA-only and SA-PSY patients. More counseling sessions devoted to substance abuse and family problems, and increased involvement in 12-step activities partially counteracted the negative effects of having a PTSD diagnosis on several outcomes. SA-PTSD patients reported fewer psychological symptoms at discharge in programs that were high in support and order/organization. 相似文献
993.
We studied the effect of endogenous adenosine on the release of [3H]acetylcholine ([3H]ACh) in cultures enriched (96.4+/-0.4%) in rat cholinergic amacrine-like neurons, as determined by labeling with an antibody against choline acetyltransferase. A small population of these cells also contained GABA. Using these cultures we observed that both [3H]ACh release, which was largely Ca2+-dependent, and 45Ca2+ influx, evoked by depolarization with 50 mM KCl, were increased when adenosine A1 receptor activation was prevented by removal of endogenous adenosine with adenosine deaminase, or by application of the A1 receptor antagonist DPCPX. Our results indicate that, in cultured rat amacrine-like neurons, the activation of A1 receptors decreases calcium influx and, thereby, inhibits [3H]ACh release. 相似文献
994.
DO Freedman 《Canadian Metallurgical Quarterly》1998,12(2):543-547
As travel medicine practices expand and multiply, practitioners increasingly need to be familiar with constantly changing disease epidemiology and drug resistance patterns in over 220 different countries. Nowadays, keeping current means utilizing the wide array of resources available on the internet. This article contains background information on the most relevant travel medicine-oriented Internet sites and provides their universal resource locators in a convenient table. 相似文献
995.
CB López AM Kalergis MI Becker JA Garbarino AE De Ioannes 《Canadian Metallurgical Quarterly》1998,117(3):194-201
Nitric oxide (NO) reduces platelet aggregation in vitro. However, repeated measurements of platelet aggregation in infants and small children are impossible due to the large blood samples required. Instead, the expression of different platelet receptors mediating platelet adhesion (CD 36 and CD 42b), activation (CD 42b and CD 61) and aggregation (CD 41a) was measured repeatedly by flow cytometry. First, the expression of platelet receptors was quantified in platelet suspensions of 20 healthy volunteers after incubation with different concentrations of NO (0, 25, 100 and 640 ppm) and compared to changes in platelet aggregation and intrathrombocytic cGMP levels. It was then studied in 21 infants and children before, during and up to 3 days after cardiopulmonary bypass surgery. Seven of these patients required NO inhalation postoperatively. The in vitro experiments showed a reduced expression of the CD 41a, CD 42b and CD 61 receptors with increasing doses of NO, predominantly affecting the CD 41a receptor (-11% at 100 ppm and -20% at 640 ppm). This significant effect is in keeping with the observed NO-induced inhibition of platelet aggregation (-44% at 100 ppm) and the rise in platelet cGMP levels (+69% at 100 ppm). In patients without inhaled NO, the expression of CD 41a was slightly attenuated during cardiopulmonary bypass surgery (-15%) but increased significantly afterwards (2 h: +31%, 1st day: +129%, 2nd day: +120%, 3rd day: +111%). Comparable results were obtained regarding the other adhesion molecules CD 36, CD 42b and CD 61. In patients with inhaled NO the same pattern was observed and analysis of variance did not reveal any significant difference between both groups of patients. CONCLUSIONS: NO (> or = 100 ppm) decreases the expression of different platelet adhesion molecules and platelet aggregation, presumably via an increase in intracellular cGMP. However, due to the low dose range used in the clinical setting (1-40 ppm) this is clinically not relevant. Immediately after cardiopulmonary bypass surgery the expression of these adhesion molecules is reduced, but recovers on the 1st postoperative day. 相似文献
996.
JM G?tz CI van Kan HW Verspaget I Biemond CB Lamers RA Veenendaal 《Canadian Metallurgical Quarterly》1996,38(4):502-506
BACKGROUND: The mucosal pathology of Helicobacter pylori infection may in part be due to excessive production of reactive oxygen metabolites (ROMs) by phagocytes. The influence of H pylori infection on mucosal superoxide dismutases, some major scavenger enzymes of ROM was investigated. In humans superoxidase dismutase is present in at least two forms-that is, mitochondrial manganese (Mn)-superoxide dismutase and cytoplasmic copper-zinc (CuZn)-superoxide dismutase. METHODS: The amount and activity of both superoxide dismutases were measured, respectively by enzyme linked immunosorbent assay (ELISA) and spectrophotometrical enzyme activity assay, in gastric biopsy homogenates of patients with normal mucosa (n = 39) and in patients with H pylori related gastritis (n = 71). Infection and gastritis were confirmed by a combination of culture, serology, and histology. RESULTS: The amount (p < 0.001) and activity (p < or = 0.05) of Mn-superoxide dismutase were increased by about twofold to three-fold, whereas the amount and activity of CuZn-superoxide dismutase showed a slight decrease in gastric mucosa of patients with H pylori gastritis, in both antrum and corpus, compared with normal mucosa of patients without H pylori infection. Mn-superoxide dismutase concentrations in biopsy specimens of histologically normal corpus from patients with an inflamed antrum were significantly higher (p < 0.01) than that of patients with a histologically normal antrum. CONCLUSION: H pylori infection has a differential effect on mitochondrial and cytoplasmic superoxide dismutase in the gastric mucosa, reflected by a pronounced increase in the cytokine inducible Mn-superoxide dismutase and a marginal decrease in the constitutive CuZn-superoxide dismutase. 相似文献
997.
VA Moisés CB Mesquita O Campos JL Andrade J Bocanegra JC Andrade E Buffolo AC Carvalho 《Canadian Metallurgical Quarterly》1998,11(12):1139-1144
The goal of this study was to assess left ventricular segmental wall motion (SWM) abnormalities during coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB), and its impact on the immediate postoperative outcome. Transesophageal echocardiography was used intraoperatively in 27 patients (mean age 57 years) who had CABG without CPB. Images obtained with a 5-MHz biplane transesophageal echocardiographic probe in the transgastric and transesophageal planes were recorded before, during, and after 48 coronary artery clampings for saphenous vein or internal mammary artery anastomosis. Transthoracic echocardiography was performed 1 day before surgery and on the seventh postoperative day. During the 48 coronary artery clampings, 31 (64%) new SWM abnormalities were found. At the time of chest closure, complete recovery occurred in 16 (50%) segments, partial recovery in 10 (33%), and no recovery in 5 (17%). On the seventh postoperative day the new SWM abnormalities persisted in all 5 segments without recovery at the end of the surgery and in 2 of 10 (20%)segments with partial recovery (group 1). Group 1 had higher variation on the echocardiographic point score index between the beginning and end of surgery, higher enzymatic levels, more ST-T changes on the electrocardiogram, and more clinical problems than group 2 (patients without new SWM abnormalities on the seventh postoperative day) (P < .05). We concluded that new SWM abnormalities of the left ventricle occur during CABG without CPB as assessed by intraoperative transesophageal echocardiography. Persistence of these abnormalities at the end of surgery may be a predictor of SWM dysfunction and clinical problems in the immediate postoperative period. 相似文献
998.
999.
The NOD mouse is a model of human IDDM, which is characterized by a cell-mediated autoimmune process resulting in spontaneous diabetes. Alpha-interferon (IFN-alpha) is thought to play a pathogenic role in this autoimmune process. We report that recombinant alpha-interferon (rIFN-alpha) administration decreases the development of spontaneous diabetes and the passive transfer of diabetes in NOD mice. Spontaneous diabetes was inhibited by IFN-alpha in a dose-dependent fashion. A dose of as little as 20 x 10(3) U inhibited diabetes development, while a dose of 100 x 10(3) U potently prevented diabetes (14% incidence vs. 70% incidence in control mice). Even at the termination of the experiment, nondiabetic mice administered rIFN-alpha maintained normal glucose tolerance. Islet inflammation was 65% lower in the pancreases of rIFN-alpha mice. rIFN-alpha administration decreased anti-islet effector cell bioactivity of spleen cells without inducing generalized immunosuppression. Passive transfer experiments demonstrated that the decreased anti-islet effector cell activity was not a direct action of rIFN-alpha on these cells. In conclusion, rIFN-alpha potently and paradoxically prevents diabetes by indirectly decreasing anti-islet effector cell activity and in turn the development of insulitis without inducing generalized immunosuppression. This work, which goes against our current understanding of the role of rIFN-alpha in autoimmunity, may have significant implications to further our understanding of the pathogenesis of IDDM and to further the development of novel modes to prevent the disease. 相似文献
1000.
AW Walter ML Hancock CH Pui MM Hudson JS Ochs GK Rivera CB Pratt JM Boyett LE Kun 《Canadian Metallurgical Quarterly》1998,16(12):3761-3767
PURPOSE: To evaluate the incidence of and potential risk factors for second malignant neoplasms of the brain following treatment for childhood acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS: The study population consisted of 1,612 consecutively enrolled protocol patients treated on sequential institutional protocols for newly diagnosed ALL at St Jude Children's Research Hospital (SJCRH) between 1967 and 1988. The median follow-up duration is 15.9 years (range, 5.5 to 29.9 y). RESULTS: The cumulative incidence of brain tumors at 20 years is 1.39% (95% confidence interval [CI], 0.63% to 2.15%). Twenty-two brain tumors (10 high-grade gliomas, one low-grade glioma, and 11 meningiomas) were diagnosed among 21 patients after a median latency of 12.6 years (high-grade gliomas, 9.1 years; meningiomas, 19 years). Tumor type was linked to outcome, with patients who developed high-grade tumors doing poorly and those who developed low-grade tumors doing well. Risk factors for developing any secondary brain tumor included the presence of CNS leukemia at diagnosis, treatment on Total X therapy, and the use of cranial irradiation, which was dose-dependent. Age less than 6 years was associated with an increased risk of developing a high-grade glioma. CONCLUSION: This single-institution study, with a high rate of long-term data capture, demonstrated that brain tumors are a rare, late complication of therapy for ALL. We report many more low-grade tumors than others probably because of exhaustive long-term follow-up evaluation. The importance of limiting cranial radiation is underscored by the dose-dependent tumorigenic effect of radiation therapy seen in this study. 相似文献