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121.
T Hoshino L A Rodriguez K G Cho K S Lee C B Wilson M S Edwards V A Levin R L Davis 《Journal of neurosurgery》1988,69(6):839-842
The proliferative potential of low-grade astrocytomas was estimated in 47 patients. Each patient received an intravenous infusion of bromodeoxyuridine (BUdR), 150 to 200 mg/sq m, at the time of craniotomy to label cells in deoxyribonucleic acid (DNA) synthesis; the percentage of S-phase cells, or BUdR labeling index (LI), of each tumor was determined immunohistochemically. In 29 patients (60%), the tumors had BUdR LI's of less than 1%, indicating a slow growth rate; only three (10%) of these patients died of recurrent tumor during a follow-up period of up to 3 1/2 years. In contrast, of the 18 patients (40%) whose tumors had BUdR LI's of 1% or more, 12 (67%) had a recurrence and nine died during the same follow-up period. These results show that the proliferative potential, as reflected by the BUdR LI, is an important prognostic factor that separates low-grade astrocytomas into two groups and provides a more scientific rationale for selecting treatment for individual patients. 相似文献
122.
123.
D G Burrin R J Shulman P J Reeds T A Davis K R Gravitt 《The Journal of nutrition》1992,122(6):1205-1213
Our objective was to determine the relative contributions of protein synthesis and protein absorption in the rapid accretion of gastrointestinal protein in suckling piglets during the early neonatal period. We measured the rates of tissue protein synthesis using a flooding dose of L-[4-3H]phenylalanine in various visceral and peripheral tissues of neonatal piglets fed water, mature milk or colostrum for 6 h. The jejunal and ileal protein synthesis rates in piglets fed either colostrum or milk were three- to fourfold higher than in piglets fed water. The increased jejunal and ileal protein synthesis could not, however, account for the differences in protein mass between the colostrum-fed and water-fed groups. The relative abundance of IgG, a major porcine colostral protein, in jejunal tissue was markedly higher in piglets fed colostrum than in piglets fed either milk or water. The fractional protein synthesis rates in liver, kidney, spleen and skeletal muscle and the absolute protein synthesis rates in liver and spleen were also greater in piglets fed colostrum than in those fed milk or water. Increased endogenous protein synthesis made only a minor contribution to the increased intestinal protein accretion in neonatal piglets fed colostrum. A much larger proportion of this increase seemed to be a result of absorption and retention of ingested immunoglobulins. 相似文献
124.
Cabergoline: an advance in dopaminergic therapy 总被引:2,自引:0,他引:2
125.
126.
D. Davis J. Ulatowski S. Eleff M. Izuta S. Mori D. Shungu P. C. M. van Zijl 《Magnetic resonance in medicine》1994,31(4):454-460
Changes in the diffusion constant of water during reversible brain ischemia and cardiac arrest were monitored with a 10-s time resolution. Results (five cats, three rats) indicate that these changes are reversible and that the bulk of the changes are not caused by temperature or motion related to brain pulsations and blood flow. The rapid time course of the changes corresponds to the known time course for changes in energy state, signal transduction, and ionic homeostasis. 相似文献
127.
Christine B Ambrosone Mary K Nesline Warren Davis 《Cancer epidemiology, biomarkers & prevention》2006,15(9):1575-1577
The establishment of a biorepository with linkage to clinical and epidemiologic data will provide an invaluable resource for cancer research, including studies of cancer etiology, progression, and prognosis, as well as development of biomarkers for early detection. Developing an infrastructure for a biorepository linked to clinical, pathologic, and epidemiologic data requires significant efforts in strategic planning for efficient means to ascertain, identify, and consent participants, as well as guidelines for blood collection, processing, and storage while maintaining participant privacy rights. In this report, we present an approach to developing a Data Bank and Biorepository at our own institution, with discussion of elements to be considered when establishing such a bank. 相似文献
128.
129.
130.
Identification in rodents and other species of an mRNA homologous to the human beta-amyloid precursor 总被引:4,自引:0,他引:4
The isolation and sequencing of the core peptide (beta-amyloid) found in the plaques of patients with Alzheimer's disease has allowed the identification of a cDNA for the precursor protein. Using a human cDNA clone for this beta-amyloid material, we have identified an homologous mRNA (3.8 kb) in brain tissue obtained from 8 additional species. We have also determined its distribution in 7 brain regions and 12 organs obtained from rodents. A prominent, second mRNA species (2.2 kb) has been identified in rat non-neuronal tissues. The beta-amyloid gene is amply expressed in the brain of all vertebrates tested and in most rodent organs, indicating that it encodes a highly conserved and ubiquitous protein. 相似文献