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排序方式: 共有8485条查询结果,搜索用时 31 毫秒
991.
B Donahue CB Scott JS Nelson M Rotman KJ Murray DF Nelson FL Banker JD Earle JA Fischbach SO Asbell LE Gaspar AM Markoe W Curran 《Canadian Metallurgical Quarterly》1997,38(5):911-914
PURPOSE: Seven percent of patients with high grade gliomas enrolled in RTOG 83-02 had mixed astrocytoma/oligodenroglial elements on central pathology review. It has often been assumed that the most aggressive histologic component of a tumor determines biologic behavior; however in this trial, the survival of patients who had mixed glioblastomas/oligodenrogliomas was significantly longer than that of patients with pure glioblastomas (GBM). We therefore evaluated the effect of an oligodendroglial component on the survival of patients who had anaplastic astrocytomas (AAF) treated in the same trial. METHODS AND MATERIALS: One hundred nine patients who had AAF and 24 patients with mixed AAF/oligodendrogliomas (AAF/OL) were enrolled in a Phase I/II trial of randomized dose-escalation hyperfractioned radiotherapy plus BCNU. AAF/OL patients were older and more likely to have had more aggressive surgery than AAF patients. Other pretreatment characteristics were balanced between groups, as was assigned treatment. RESULTS: The median survival time for AAF was 3.0 years versus 7.3 years for AAF/OL (p = 0.019). In a multivariate analysis, adjusting for extent of surgical resection and age, an oligodendroglial component was an independent prognostic factor for survival. CONCLUSION: The results support the concept that AAFs with an oligodendroglial component have a better prognosis than pure AAF tumors, similar to the effect seen among patients with glioblastoma multiforme tumors. This better survival outcome should be taken into consideration in the design and stratification of future trials. Additionally, in contrast to patients with GBMs, patients who have AAF/OL have the potential for prolonged survival; therefore, late sequelae of treatment (both radiation and chemotherapy) must be weighed more heavily in the benefits to risks analysis. 相似文献
992.
JA Garrity 《Canadian Metallurgical Quarterly》1997,104(6):903-904
Chronic pancreas transplant rejection with enteric exocrine drainage can lead to significant long-term complications. We report a case of a 47-year-old male insulin-dependent diabetic who survived the complications of peripancreatic abscess, enterocutaneous fistula, and arterioenteric fistula related to pancreas transplantation. To avoid these long-term complications, we now recommend elective removal of nonfunctioning, enterically drained pancreas allografts. 相似文献
993.
JA Molina F de Bustos FJ Jiménez-Jiménez J Benito-León M Ortí-Pareja T Gasalla A Tallón-Barranco JA Navarro J Arenas R Enríquez-de-Salamanca 《Canadian Metallurgical Quarterly》1997,104(11-12):1287-1293
We compared CSF and serum levels, and the CSF/serum ratio of alpha-tocopherol (vitamin E), measured by HPLC, in 34 patients with Parkinson's disease (PD) and 47 controls. CSF and serum vitamin E levels were correlate. The mean CSF and serum vitamin E levels, and the CSF/serum ratio of PD patients did not differ significantly between the groups. There was no influence of antiparkinsonian therapy on CSF vitamin E levels. CSF vitamin E levels did not correlate with age, age at onset, duration of the disease, scores of the Unified Parkinson Disease Rating Scale of the Hoehn and Yahr staging in the PD group. These results suggest that CSF vitamin E concentrations are unrelated with the risk for PD. 相似文献
994.
Endocytosis and recycling of G protein-coupled receptors 总被引:1,自引:0,他引:1
Agonist stimulation of G protein-coupled receptors causes a dramatic reorganization of their intracellular distribution. Activation of receptors triggers receptor endocytosis and, since receptors recycle back to the surface continuously, a new steady state is reached where a significant proportion of receptors is located internally. Although this movement of receptors is remarkable, its role has been enigmatic. Recent developments have provided insight into the compartments through which the receptors move, the nature of the signals that trigger receptor translocation, and the significance of receptor cycling for cell function. In this article, Jennifer Koenig and Michael Edwardson review recent progress in this field and place receptor cycling into a mathematical framework that reveals the extent and rate of intracellular receptor movement. 相似文献
995.
JA Knight 《Canadian Metallurgical Quarterly》1997,27(1):11-25
Starting at infancy and continuing throughout adult life, huddling is a major component of the behavioral repertoire of Norway rats (Rattus norvegicus). Huddling behavior maintains the cohesion of litters throughout early life, and in adulthood, it remains a consistent feature of social behavior of R. norvegicus. During infancy, rats have severely limited sensorimotor capabilities, and yet they are capable of aggregating and display a form of group regulatory behavior that conserves metabolic effort and augments body temperature regulation. The functions of huddling are generally understood as group adaptations, which are beyond the capabilities of the individual infant rat. We show, however, that huddling as aggregative or cohesive behavior can emerge as a self-organizing process from autonomous individuals following simple sensorimotor rules. In our model, two sets of sensorimotor parameters characterize the topotaxic responses and the dynamics of contact in 7-day-old rats. The first set of parameters are conditional probabilities of activity and inactivity given prior activity or inactivity and the second set are preferences for objects in the infant rat's environment. We found that the behavior of the model and of actual rat pups compare very favorably, demonstrating that the aggregative feature of huddling can emerge from the local sensorimotor interactions of individuals, and that complex group regulatory behaviors in infant rats may also emerge from self-organizing processes. We discuss the model and the underlying approach as a paradigm for investigating the dynamics of social interactions, group behavior, and developmental change. 相似文献
996.
The implantable cardioverter-defibrillator (ICD) is an implantable electronic device that has been proven to be safe and effective in treating various malignant tachyarrhythmias in susceptible individuals. As the use of ICDs becomes more widespread, more individuals with the implanted devices will be encountered at autopsy. Manipulation of an activated ICD can result in electrical shock. To avoid injury, pathologists must be properly prepared to deal with bodies containing activated ICDs. These devices can also provide valuable information that may be helpful in determining the cause and mechanism of death. Herein, we present information regarding the appropriate guidelines and safeguards for pathologists confronted with an activated ICD. 相似文献
997.
We describe a case of an abdominal pregnancy which presented in the first trimester with rapid accumulation of blood stained ascites. The ascites resolved completely following surgical removal of a gestational sac from the peritoneal cavity. The pathophysiology of ascites in this case may be similar to that in cases of ascites in other non-malignant gynaecological conditions. 相似文献
998.
E Tobajas Asensio E Boada Apilluelo JA Tobajas Asensio MA Simón Marco JM Artigas Martín 《Canadian Metallurgical Quarterly》1997,14(11):569-572
A hundred and fifty patients with jaundice and analytical suspicion of extrahepatic cholestasis were studied prospectively; history, laboratory investigation and ultrasound examination were realized. Computerized tomography was performed in 146 patients. Ultrasonography and computerized tomography findings were confirmed by CPRE o CPTH and surgery. Ultrasonography has a sensitivity of 92.6% while that of computerized tomography was 87.2% for the identification of dilated biliary ducts. The accuracy of ultrasonography was higher than the one obtained in computerized tomography in cholangiocarcinoma (sensitivity: 77.7%) and gallbladder carcinoma (sensitivity: 100%). Computerized tomography recognized choledocholithiasis (sensitivity: 83.3%) and ampullary carcinoma (sensitivity: 88.8%) with better accuracy. However for pancreatic carcinoma (sensitivity: 88.8%) and pancreatitis (sensitivity: 83.3%) both examinations had the same accuracy. 相似文献
999.
JA Ratón I Pocheville JM Vicente R González I Bilbao C Gutierrez JL Díaz-Pérez 《Canadian Metallurgical Quarterly》1997,14(5):365-368
The present paper addresses mortality from urinary diseases (ICD9 codes 580-599) in the Italian pediatric population aged 0-19 years, in the period 1979-91. Mortality data were obtained from the Italian National Statistical Institute (ISTAT). A total number of 522 deaths were recorded among people aged 0-19 years, amounting to 0.33% of all casualties. Half of these deaths were due to renal failure (ICD9 codes: 584-586). While mortality from all causes decreased by 35% among the Italian pediatric population, mortality from urinary diseases remained stable during the same period, and even increased in the age range 0-4 years (from 3.47 per million person-years in 1979 to 9.83 per million person-years in 1990; p < 0.001). This outbreak in mortality was entirely due to an increase in casualties from acute renal failure (ICD9 code: 584). In conclusion, since the increase in mortality from urinary diseases among Italian children aged 0-4 years takes place in the presence of a substantial drop in mortality from all causes, attention should be paid to this problem and surveillance systems should be reinforced. 相似文献
1000.
Nutritional strategies for promoting fat utilization and delaying the onset of fatigue during prolonged exercise 总被引:1,自引:0,他引:1
EV Lambert JA Hawley J Goedecke TD Noakes SC Dennis 《Canadian Metallurgical Quarterly》1997,15(3):315-324
With increasing human age (20-80 years), the electroencephalogram (EEG) dose requirement for the intravenous anesthetic thiopental decreases approximately 10% per decade of life. The goal of this study was to compare the dose required to attain isoelectric EEG in young (4-5 month) vs. aged (24-25-month) Fischer 344 rats. One second isoelectricity was found to be an endpoint where minimal cardiorespiratory depression occurred. The effects of age, infusion rate, and repeated administration were examined in nine young and nine old rodents. Thiopental dose requirement increased with increasing infusion rates. Repeated administration at two-day intervals did not demonstrate tolerance to thiopental. No difference in thiopental dose requirement was detected in the young vs. elderly rats. In a separate group of five young and five old rats, thiopental plasma, brain, heart, and CSF concentrations were measured when five seconds of EEG isoelectricity was achieved: no consistent differences were noted. The rat may not be an appropriate model to investigate acute age-related anesthetic effects in humans, because cardiovascular changes with age are dissimilar between species. 相似文献