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The California Tumor Registry was started in 1947. It consists of case abstracts of medical records on neoplasm patients seen in 40 hospitals in California and now contains data on more than 159,000 cases, with 15,000 new cases being added each year. Follow-up reports are requested annually on each case not known to be dead. The Registry is designed to (1) promote the continuing care of the patient, (2) to evaluate cancer control methods, (3) to advance knowledge of the epidemiology of cancer, and (4) to suggest leads for laboratory and clinical research. From a series of 110,628 neoplasm cases reported to the California Tumor Registry in 1942-1954, data are presented on 76,499 cancer cases initially diagnosed in reporting hospitals. Histopathologic confirmation, age, sex, stage, treatment, follow-up, and survival of cancer patients are discussed. Use of the Registry information for analyzing cancer experience for epidemiological study and for evaluation of treatment methods are also described. The report is intended to illustrate the types of data that can be obtained from the California Tumor Registry. More comprehensive reports on specific aspects of cancer control will be forthcoming.  相似文献   
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SYNOPSIS Deamination at pH 7.5 of adenosine, deoxyadenosine, cytidine and deoxycytidine by cell-free preparations of Tetrahymena pyriformis W was observed both in the presence and absence of fluoride. Deamination of 5′-AMP, 5′-dAMP, 5′-CMP, and 5′-dCMP was found only in the absence of fluoride. Dephosphorylation of the above nucleotides by acid phosphatases occurred at pH 4.5; reduced activity was noted at pH 7.5. Fluoride effectively blocked acid phosphatase activity at both pH values. This correlation of phosphatase and deaminase activities suggests a catabolic pathway for 5′-AMP and 5′-CMP whereby dephosphorylation precedes deamination. Radiolabelled substrates were used to test this hypothesis. The experiments were designed so that conversion of as little at 1.0% of the radiolabelled substrate to the deaminated product could be detected. No 5′-IMP or 5′-UMP, the expected deamination products of 5′-AMP and 5′-CMP, respectively, was recovered after incubation of the radiolabelled substrates with cell-free enzyme preparations. Thus, it appears that Tetrahymena has no 5′-AMP or 5′-CMP deaminases and that these compounds are deaminated only after conversion to nucleosides. Acid phosphatase activity toward 5′-GMP, 5′-dGMP, 5′-TMP, 5′-UMP, and 5′-XMP was also found.  相似文献   
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Epimastigotes of Trypanosoma cruzi, Peru strain, incubated in Contreras' artificial triatomine urine transformed into metacyclic trypomastigotes when 10 mM L-glutamine, L-asparagine or D-fructose was added to the medium. Metacyclogenesis with these substrates was comparable to the percent metacyclic morphotype formation induced by L-proline and significantly greater than that stimulated by 10 mM D-glucose. Sodium acetate (10 mM) increased transformation induced by L-proline, and L-hydroxyproline (10 mM) increased transformation induced by D-fructose. Phosphoenolpyruvate (10 mM) inhibited L-proline-induced metacyclic trypomastigote stage formation. Three antimetabolites, azetidine 2-carboxylate (5 mM), malonic acid (1 mM), and desthiobiotin (5 mM), completely inhibited D-fructose-induced but not L-proline-induced transformation. The Costa Rica, Y, and CL strains of T. cruzi showed different patterns of percent metacyclogenesis with substrates that induce transformation in the Peru strain.  相似文献   
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ABSTRACT Estimation of abundance is important for assessing population responses to management actions. Accurate abundance estimates are particularly critical for monitoring temporal variation following reintroductions when the management goal is to attain population sizes capable of sustaining harvest. Numerous reintroductions have taken place in the Great Lakes region of North America, including efforts to restore extirpated fishers (Martes pennanti) and American martens (M. americana). We used a DNA-based noninvasive hair-snaring method based on one trap design and trapping -grid configuration, and evaluated capture—mark—recapture (CMR) analytical approaches to simultaneously estimate population size for co-distributed fishers and American martens in a 671-km2 area of the Ottawa National Forest in the western Upper Peninsula of Michigan, USA. We included harvest as a final recapture period to increase probability of recapture and to evaluate potential violations of geographic closure assumptions. We used microsatellite markers to identify target species, eliminate congener species, and provide individual identity for estimation of abundance. Population estimates for fishers and martens on the study area ranged from 35 to 60 and 8 to 28, respectively. Estimators incorporating harvest data resulted in up to a 40% increase in abundance estimates relative to estimators without harvest. We considered population estimates not including harvest data the most appropriate for the study due to timing of sampling and environmental factors, but inclusion of harvested individuals was shown to be useful as a means to detect violations of the assumption of geographic closure. We suggest improvements on future CMR sampling designs for larger landscape scales of relevance to management through incorporation of habitat or historical harvest data. Noninvasive genetic methods that simultaneously estimate the numerical abundance of co-distributed species can greatly decrease assessment costs relative to traditional methods, and increase resulting demographic and ecological information.  相似文献   
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