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891.
KW Gripp RA Zimmerman ZJ Wang LB Rorke AC Duhaime L Schut PT Molloy SH Tucker EH Zackai M Muenke 《Canadian Metallurgical Quarterly》1998,19(7):1368-1372
We report the imaging findings in five patients with a unique dysmyelinating disorder. MR studies of these infants showed obstructive hydrocephalus caused by mass effect produced by an enlarged cerebellum. The white matter of an enlarged cerebrum and cerebellum showed delayed myelination. Proton spectroscopy showed normal N-acetylaspartate (NAA) levels. While the dysmyelinating disorder was clearly differentiated from Canavan disease by an absence of elevated NAA and differing histopathologic findings and autosomal-dominant inheritance pattern, there were similarities to this disease in the presentation and, to some extent, in the initial imaging findings. 相似文献
892.
L Geng M Solimena RA Flavell RS Sherwin AC Hayday 《Canadian Metallurgical Quarterly》1998,95(17):10055-10060
Glutamic acid decarboxylase (GAD)65 is a pancreatic beta cell autoantigen implicated as a target of T cells that initiate and sustain insulin-dependent diabetes mellitus (IDDM) in humans and in non-obese diabetic (NOD) mice. In an attempt to establish immunological tolerance toward GAD65 in NOD mice, and thereby to test the importance of GAD in IDDM, we generated three lines transgenic for murine GAD65 driven by a major histocompatibility complex class I promoter. However, despite widespread transgene expression in both newborn and adult mice, T cell tolerance was not induced. Mononuclear cell infiltration of the islets (insulitis) and diabetes were at least as bad in transgenic mice as in nontransgenic NOD mice, and in mice with the highest level of GAD65 expression, disease was exacerbated. In contrast, the same transgene introduced into mouse strain, FvB, induced neither insulitis nor diabetes, and T cells were tolerant to GAD. Thus, the failure of NOD mice to develop tolerance toward GAD65 reflects at minimum a basic defect in central tolerance, not seen in animals not predisposed to IDDM. Hence, it may not be possible experimentally to induce full tolerance toward GAD65 in prediabetic individuals. Additionally, the fact that autoimmune infiltration in GAD65 transgenic NOD mice remained largely restricted to the pancreas, indicates that the organ-specificity of autoimmune disease is dictated by tissue-specific factors in addition to those directing autoantigen expression. 相似文献
893.
The long-term clinical effects of soy protein containing various amounts of isoflavones on lipoproteins, mononuclear cell LDL receptor messenger RNA concentrations, and other selected cardiovascular risk factors are not well known. Sixty-six hypercholesterolemic, free-living, postmenopausal women were investigated during a 6-mo parallel-group, double-blind trial with 3 interventions. After a control period of 14 d, all subjects were randomly assigned to 1 of 3 dietary groups (all with 40 g protein): a National Cholesterol Education Program (NCEP) Step 1 diet with protein from casein and nonfat dry milk (control), an NCEP Step 1 diet with protein from isolated soy protein containing moderate amounts of isoflavones (ISP56), or an NCEP Step 1 diet with protein from isolated soy protein containing high amounts of isoflavones (ISP90). Non-HDL cholesterol in both the ISP56 and ISP90 groups was reduced compared with the control group (P < 0.05), whereas total cholesterol was not changed. HDL cholesterol increased in both the ISP56 and ISP90 groups (P < 0.05), whereas the ratio of total to HDL cholesterol decreased significantly in both groups compared with the control (P < 0.05). Mononuclear cell LDL receptor messenger RNA concentrations increased in subjects consuming ISP56 or ISP90 compared with the control (P < 0.05). These results indicate that soy protein, with different amounts of isoflavones, may decrease the risk of cardiovascular disease via improved blood lipid profiles, and that the mechanism by which apolipoprotein B-containing lipoproteins were depressed may be via alterations in LDL receptor quantity or activity. 相似文献
894.
BA Finette B Rood T Poseno P Vacek S Pueschel AC Homans 《Canadian Metallurgical Quarterly》1998,403(1-2):35-43
Sixty-six human enterovirus serotypes have been described using antibody neutralization, with antigenic variants defined within several serotypes. Despite the availability of sequence data for numerous enteroviruses, the molecular basis of serotype is unknown. Previous studies by others have identified four major phylogenetic groups within the human enteroviruses, but there has been no complete database of homologous sequences for all human enterovirus serotypes. We have determined the homologous partial VP2 sequences for the 12 prototype strains for which VP2 sequence was unavailable and for eight well-characterized antigenic variants. Phylogenetic analysis of all prototype strains produced four major groups, consistent with published enterovirus phylogenies. Many antigenic variants, however, failed to cluster with their respective prototype strains, suggesting that this portion of VP2 may be inappropriate for consistent molecular inference of serotype and for detailed study of enterovirus evolution. 相似文献
895.
896.
897.
AC King JF Sallis AL Dunn DG Simons-Morton CA Albright S Cohen WJ Rejeski BH Marcus MC Coday 《Canadian Metallurgical Quarterly》1998,30(7):1086-1096
Counseling by health care providers has the potential to increase physical activity in sedentary patients, yet few studies have tested interventions for physical activity counseling delivered in health care settings. The Activity Counseling Trial (ACT) is a 5-yr randomized clinical trial to evaluate the efficacy of two primary care, practice-based physical activity behavioral interventions relative to a standard care control condition. A total of 874 sedentary men and women, 35-75 yr of age, have been recruited from primary care physician offices at three clinical centers for 2 yr of participation. They were randomly assigned to one of three experimental conditions that vary, in a hierarchical fashion, by level of counseling intensity and resource requirements. The interventions, which are based on social cognitive theory and the transtheoretical model, are designed to alter empirically based psychosocial mediators that are known to be associated with physical activity. The present paper describes the theoretical background of the intervention, the intervention methods, and intervention training and quality control procedures. 相似文献
898.
RG Stock AC Ferrari NN Stone 《Canadian Metallurgical Quarterly》1998,12(10):1467-72; discussion 1472, 1475-6
The optimal management of patients with lymph node-positive prostate cancer remains controversial. The role of pelvic irradiation in patients at high risk for nodal involvement continues to be debated. Studies of prostate irradiation with and without inclusion of the pelvic lymph nodes show poor outcomes for node-positive patients, supporting the concept that many of these patients have systemic disease at presentation. Although no randomized trial has examined the role of pelvic irradiation in pathologically node-positive patients, available data fail to reveal any significant benefit of this approach over prostate-alone irradiation. More promising therapeutic approaches involve the combination of local therapy and sustained hormonal therapy. Series comparing prophylactic irradiation of the pelvis and prostate to irradiation of the prostate alone have shown no clear benefit of pelvic irradiation. Pelvic irradiation may play a role in the treatment of early-stage or occult nodal disease, although this has yet to be examined. Until prospective, randomized trials demonstrate the efficacy of pelvic irradiation in the management of prostate cancer, its use cannot be routinely recommended. Data support the use of lymphadenectomy in high-risk patients to identify those with positive nodes, since these patients require androgen withdrawal therapy. 相似文献
899.
AC Moberg G Ahlberg CE Leijonmarck A Montgomery O Reiertsen AR Rosseland R Stoerksson 《Canadian Metallurgical Quarterly》1998,164(11):833-40; discussion 841
OBJECTIVE: To evaluate the efficacy of diagnostic laparoscopy in patients with suspected acute appendicitis, the number of complications associated with the laparoscopic technique, and the effect of leaving a macroscopically normal-looking appendix in place. DESIGN: Three prospective protocols. SETTING: Three departments of surgery, one in Norway and two in Sweden. SUBJECTS: 1043 patients aged 15 years or over. INTERVENTIONS: Diagnostic laparoscopy in patients with signs and symptoms of acute appendicitis who were to be operated on. MAIN OUTCOME MEASURES: Morbidity, mortality, and histological appearance of removed appendices, and outcome whether or not the patient was operated on. RESULTS: 819 patients had appendectomies (61% laparoscopically and 39% by conversion to open operation) with a total complication rate of 10%. In 211 patients a diagnostic laparoscopy was done as a single procedure. There were 181 women in this group and 86 of them had gynaecological disorders. The complication rate was 2% among these 211 patients and after a follow up of two years no patients had been readmitted for appendicectomy. 13 patients were subjected to other open procedures. The overall mortality was 0.4%. CONCLUSION: Diagnostic laparoscopy is safe and can be recommended in patients with suspected acute appendicitis, particularly in women. A macroscopically normal-looking appendix can be left in place. 相似文献
900.
MG Hobart CS Modlin A Kapoor N Boparai B Mastroianni D Papajcik SM Flechner DA Goldfarb R Fischer KJ O'Malley AC Novick 《Canadian Metallurgical Quarterly》1998,66(12):1689-1694
BACKGROUND: To maximize the renal donor pool, cadaveric pediatric en bloc kidneys have been transplanted as a dual unit by some transplant centers. We compared the short- and long-term outcomes of adult recipients of cadaveric pediatric en bloc renal transplants versus those of matched recipients of cadaveric adult kidneys. METHODS: Thirty-three adults who received pediatric en bloc kidney transplants between April 1990 and September 1997 were retrospectively identified and were compared with 33 matched adults who received adult cadaveric kidney transplants. The groups were identical for transplantation era, immunosuppression, recipient sex, race, cause of renal failure, mean weight, and follow-up duration (37.8 vs. 37.5 months). The mean recipient age study versus control was lower (36.3 vs. 48.9 years, P=0.0003). Results. There was no difference between the en bloc and adult donor groups in the 3-year patient survival rates (95% vs. 87%, P=0.16) or the 3-year graft survival rates (87.3% vs. 84.2%, P=0.35). Further, there was no difference in en bloc patient or en bloc graft survival time stratified by recipient age (14-44 vs. >45 years, P=0.11), en bloc donor age (<24 vs. >24 months, P=0.39), or recipient weight (<60, 61-75, >75 kg; P=0.60). Differences in serum creatinine (mg/dl) for the en bloc versus the control group at the time of discharge (3.0 vs. 7.8 mg/dl, P=0.06), at 1 year (1.4 vs. 2.0 mg/dl, P=0.06), and at 2 years (1.1 vs. 1.6 mg/dl, P=0.14) had dissipated by the time of the 5-year follow-up examination (1.1 vs. 1.6 mg/dl, P=0.14). Vascular complications were more prevalent in the en bloc group: renal vein thrombosis (one case), thrombosis of donor aorta (two cases), arterial thrombosis of one renal moiety (two cases), and renal artery stenosis (two cases). There were no differences between groups in delayed graft function, acute or chronic rejection, posttransplant hypertension, posttransplant protein-uria, or long-term graft function. CONCLUSIONS: Collectively, these data indicate that transplanting pediatric en bloc kidneys into adult recipients results in equivalent patient and graft survival compared with adult cadaveric kidneys. Further, the data also suggest that pediatric en bloc kidneys need not be strictly allocated based on recipient weight or age criteria. 相似文献