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991.
JG Jarvik KR Maravilla DR Haynor M Levitz RA Deyo 《Canadian Metallurgical Quarterly》1997,204(2):447-454
PURPOSE: To demonstrate the feasibility of a randomized trial to compare rapid magnetic resonance (MR) imaging with plain radiography as the initial imaging study in patients with low back pain, to test measures of the decision-making process and patient outcomes, and to offer a model for using randomized clinical trials to evaluate diagnostic tests. MATERIALS AND METHODS: The authors randomly selected 62 patients with low back pain to undergo either rapid MR imaging or plain radiography. The authors measured functional status, satisfaction, and general health status at baseline and at 3 months. The modified Roland scale was the primary outcome measure. In addition, the authors examined diagnostic and therapeutic decision making and resources used by each group. RESULTS: There were no statistically significant differences between the two patient groups with respect to outcome (Roland score: MR imaging = 12.5, radiography = 12.1). MR imaging provided more useful information to clinicians and resulted in greater patient reassurance. CONCLUSION: Randomly selecting patients to undergo imaging examinations and measuring outcomes is feasible; however, a larger, multicenter study is necessary to determine whether rapid MR imaging is a cost-effective replacement for plain radiography in patients with low back pain. 相似文献
992.
LP Boulet KR Chapman J C?té S Kalra R Bhagat VA Swystun M Laviolette LD Cleland F Deschesnes JQ Su A DeVault RB Fick DW Cockcroft 《Canadian Metallurgical Quarterly》1997,155(6):1835-1840
Inhaled allergens, acting through IgE-dependent mechanisms, are important triggers of asthma symptoms and inducers of airway hyperresponsiveness and airway inflammation. The effect of anti-IgE recombinant humanized monoclonal antibody-E25 (rhuMAb-E25) on the provocation concentration of allergen causing a 15% fall in FEV1 (allergen PC15) during the allergen-induced early asthmatic response (EAR) was assessed in a multicenter, randomized, double-blind, parallel group study. Ten of 11 allergic asthmatic subjects randomized to receive intravenous rhuMAb-E25, 2 mg/kg on study day 0 and 1 mg/kg on Days 7, 14, 28, 42, 56, and 70 completed the study; nine received intravenous placebo. The allergen PC15 was measured on Days -1, 27, 55, and 77 and methacholine PC20 on Days -2, 42, and 76. rhuMAb-25 was well tolerated and only one patient (active group) was withdrawn because of a generalized urticarial rash after the first dose. Compared with baseline values (Day -1), the median allergen PC15 on Days 27, 55, and 77 were increased by 2.3, 2.2, and 2.7 doubling doses (delta log PC15/0.3) respectively with rhuMAb-E25 and -0.3, +0.1, and -0.8 doubling doses with placebo (p < or = 0.002). Methacholine PC20 improved slightly after rhuMAb-E25, this change becoming statistically significant on Day 76 (p < 0.05); no change was observed in the placebo group. Mean serum-free IgE fell by 89% after rhuMAb-E25 while there was no significant change after placebo. The inhibitory effects of rhuMAb-E25 on allergen-induced EAR suggest that it may be an effective, novel antiallergic treatment for asthma. 相似文献
993.
QT Le MD Weil WM Wara KR Lamborn MD Prados MS Edwards PH Gutin 《Canadian Metallurgical Quarterly》1997,3(4):238-245
PURPOSE: This analysis aimed to review the experience in the management of adult medulloblastoma at the University of California, San Francisco, and to identify important prognostic factors for survival and posterior fossa control. PATIENTS AND METHODS: We performed a retrospective review of 34 adult patients, age > or = 15, with cerebellar medulloblastoma treated with radiotherapy at the University of California, San Francisco from 1970 to 1994. All patients underwent a surgical procedure (complete resection in 17, subtotal resection in 10, and biopsy alone in seven), followed by craniospinal irradiation. Most patients treated after 1979 also received chemotherapy. Twenty were classified as poor-risk due to either incomplete resection or evidence of disease outside of the posterior fossa at diagnosis. RESULTS: The 5-year posterior fossa control and overall survival rates were 61% and 58%, respectively. The majority of relapses occurred in the posterior fossa (14 of 17). Multivariate analysis revealed that age (favoring older patients), gender (favoring female patients), and extent of disease at diagnosis (favoring localized disease) were important prognostic factors for posterior fossa control. There was a trend toward improved posterior fossa control with higher radiation dose to the posterior fossa in patients with a complete resection. Gender and extent of disease at presentation were significant prognostic factors for survival. The 5-year survival rates were 92% for female patients versus 40% for male patients, and 67% for patients with localized disease versus 25% for those with disseminated disease. The prognosis following recurrence was poor; all died of the disease. DISCUSSION: Survival for adult medulloblastoma was comparable to its pediatric counterpart. In patients with localized disease at presentation, gender (favoring female patients) and age (favoring older patients) were important prognostic factors for posterior fossa control and survival. In patients with disseminated disease at presentation, the prognosis is poor, and innovative therapy is needed to improve survival. 相似文献
994.
R Bettencourt H Lanz-Mendoza KR Lindquist I Faye 《Canadian Metallurgical Quarterly》1997,250(3):630-637
The isolation of antibacterial peptides from the giant silkmoth Hyalophora cecropia has opened the area of animal antibiotics [Boman, H. G. (1991) Cell 65, 205-207] and the study of insect immune genes has revealed striking similarities to many immune response genes in mammals [Hultmark, D. (1994) Nature 267, 116-117]. However, the molecules and mechanisms behind primordial immune recognition are not understood. One candidate for one such recognition molecule is hemolin, a 48-kDa immunoglobulin-related protein first isolated from H. cecropia, where it is up-regulated upon infection and secreted into the hemolymph. Hemolin was shown to bind to bacteria and to hemocytes, giving rise to changes in hemocyte adhesiveness and intracellular phosphorylation patterns [Faye, I. & Kanost, M. (1997) in Molecular mechanisms of immune responses in insects (Brey, P. T. & Hultmark, D., eds) Chapman and Hall, London]. In the present publication, we give evidence for the presence of a 52-kDa membrane form of hemolin on hemocytes, based on flow-activated cell sorting and membrane protein extractions. In addition we reveal calcium-dependent homophilic binding properties of hemolin, using hemolin-coated microspheres. When biotinylated recombinant hemolin was allowed to bind to hemocyte membranes, higher molecular-mass complexes were formed. Furthermore, we used immunological methods and Northern-blot analysis to demonstrate the presence of hemolin in embryos and retinal discs, suggesting that hemolin is expressed in several tissues at different developmental stages. These results show novel cell adhesion features of hemolin, corroborating its multifunctional character with putative roles in cellular and humoral immunity and in development. 相似文献
995.
VL Roger SJ Jacobsen PA Pellikka TD Miller KR Bailey BJ Gersh 《Canadian Metallurgical Quarterly》1998,98(25):2836-2841
BACKGROUND: The prognostic value of treadmill exercise testing (TMET) has been studied in selected populations. The generalizability of these data to different populations and to women is uncertain. METHODS AND RESULTS: A retrospective, population-based cohort study of all persons (1452 men and 741 women) who underwent TMET in years 1987 to 1989 in Olmsted County, Minnesota, was undertaken. Individuals were followed up for all-cause mortality and cardiac events (cardiac deaths, nonfatal myocardial infarction, or congestive heart failure). Sex-specific analyses were performed to determine whether the predictors of outcome and the magnitude of the associations were similar in both sexes. In men, 77 deaths and 106 cardiac events occurred during 8956 person-years of observation; in women, 46 deaths and 54 cardiac events occurred during 4801 person-years of follow-up. Exercise-induced angina, ECG changes, and workload achieved on the TMET were strongly associated with all-cause mortality and cardiac events in both sexes, and the strength of the association was similar. After adjustment, workload was the only TMET variable associated with outcome. A higher workload was associated with a reduction in the risk of cardiac events and of all-cause mortality; the protective effect of exercise capacity was strong and was similar in both sexes. CONCLUSIONS: In this population-based cohort, exercise capacity was the TMET variable that exhibited the strongest association with all-cause mortality and cardiac events. This protective effect of exercise capacity was observed in both sexes. 相似文献
996.
997.
WH Schwesinger CP Page WE Strodel AA Ghiatis S Chopra GW Gross KR Sirinek 《Canadian Metallurgical Quarterly》1998,124(4):768-71; discussion 771-2
BACKGROUND: Total parenteral nutrition is an etiologic factor in the formation of biliary sludge. We studied whether enteral nutrition is also a risk factor for sludge. METHODS: Fifty patients with a needle catheter jejunostomy (NCJ) placed during a major abdominal operation underwent preoperative and weekly postoperative ultrasonography until NCJ feedings were discontinued (1 to 6 weeks). RESULTS: All patients were men. The mean age was 63.2 +/- 1.6 years. Fourteen asymptomatic patients (28.0%) had biliary sludge within 2 weeks of beginning enteral feedings through a NCJ. Complete ultrasonographic resolution of sludge was observed in 13 of the 14 positive patients within 1 to 2 weeks of resuming an oral diet. One patient was lost to follow-up after 14 week; a positive sonogram had persisted but the patient remained asymptomatic. During the period of observation, no other patient had signs of biliary tract disease. CONCLUSIONS: (1) Biliary sludge may form in some patients during enteral feeding with NCJ. (2) Sludge is cleared by the gallbladder once an oral diet is resumed. (3) There appears to be little risk of complications during postoperative enteral feeding. 相似文献
998.
C Grunfeld W Doerrler M Pang P Jensen KH Weisgraber KR Feingold 《Canadian Metallurgical Quarterly》1997,82(11):3734-3740
Given the important role of apolipoprotein E (apoE) in triglyceride metabolism, we analyzed plasma levels and degree of sialylation of apoE in subjects with the acquired immunodeficiency syndrome (AIDS), a disorder accompanied by hypertriglyceridemia. Levels of apoE were significantly increased (1.84-fold) and correlated with plasma triglycerides (r = .663, P < .001) in AIDS. Subjects with AIDS and the apoE3/E2 phenotype showed the most prominent increases in both plasma triglyceride and apoE levels (3.4 and 2.2-fold over controls). Additionally, apoE from subjects with AIDS showed an increased amount of sialylation, compared with controls (34% increase in apoE3/E3 subjects). Increased sialylation correlated with the increase in apoE levels. In contrast, there was no increase in sialylation of apo C-III in AIDS. Thus, triglyceride levels in AIDS are influenced by apoE subtype and subjects with AIDS show changes in apoE structure. 相似文献
999.
KR Magnusson 《Canadian Metallurgical Quarterly》1997,95(3):187-202
The present study was designed to determine whether the memory sparing effects of dietary restriction during aging could be through an effect on ionotropic glutamate receptors. Quantitative autoradiography was performed on 3, 10, and 26 month old mice to examine the density changes of NMDA, AMPA and kainate binding sites in aging animals. Spatial memory performance was also tested in these mice with the use of the Morris water maze. The 10 and 26 month olds were either ad libitum-fed or diet-restricted (60% of ad libitum-fed calories). Ad libitum-fed, 26 month old mice had significant decreases in NMDA-displaceable [3H]glutamate in all ten cortical, two out of seven hippocampal, and two out of four subcortical regions, as compared to 3 month olds. Diet-restricted, 26 month old mice only differed significantly from young in three cortical and two subcortical regions. The aged ad libitum-fed mice exhibited significantly poorer performance in the spatial memory task than all other groups. The diet-restricted 26 month olds only performed significantly worse than 3 month olds and diet-restricted 10 month olds. These results suggest that some of the memory sparing effects of dietary restriction on aged animals may be due to an influence on NMDA receptors. 相似文献
1000.
DA Nichols RD Brown KR Thielen FB Meyer JL Atkinson DG Piepgras 《Canadian Metallurgical Quarterly》1997,87(3):374-380
The murine interleukin-7 (IL-7) gene was disrupted to examine the role of IL-7 in the lymphoid system. Expansion of lymphoid cells is sharply curtailed in IL-7-deficient mice. This is evident in a dramatic reduction but not elimination of lymphoid cells in the thymus, bone marrow and spleen. The few thymocytes present express CD4 and/or CD8 markers associated with T-cell maturation. Similarly, a limited number of B cells detected in the bone marrow rearrange and express immunoglobulin genes. Small but distinct populations of B and T cells are found in the spleens of IL-7-deficient mice. Thus the signal transmitted by IL-7 plays a central role in the expansion of lymphocytes while it is not absolutely required for their maturation. A transgene that directs expression of IL-7 to lymphoid cells was found to restore the numbers of thymocytes, bone marrow B-cell progenitors and splenic lymphocytes of IL-7-deficient mice to approximately normal levels. This genetic complementation confirms that the lymphoid defect is specifically due to the absence of IL-7 and demonstrates that the expansion of lymphoid cells in an organism is regulated by their exposure to IL-7. 相似文献