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V Mor S Masterson-Allen R J Goldberg F J Cummings A S Glicksman M D Fretwell 《Journal of the American Geriatrics Society》1985,33(9):585-589
Increases in cancer incidence and mortality reflect the larger numbers of elderly in the population. Using a mortality sample of 1891 biopsy-confirmed cancer patients, analyses reveal older breast, prostate, and cervical-uterine cancer victims were more likely to be diagnosed with metastases. Logistic regression analyses of subsamples of breast (N = 224), lung (N = 513), and colorectal (N = 299) cancer patients indicate that age is significantly inversely related to receipt of both subsequent chemotherapy and radiation therapy, controlling for stage of disease and presence of co-morbid disease. Exceptions to this relationship are the use of radiation therapy among nonmetastatic lung cancer patients and all breast cancer patients. The implications of these findings for current cancer control programs are discussed. 相似文献
84.
J F Noguera Aguilar I Amengual Antich A Plaza Martínez C Tortajada Collado J M Morón Canis J J Pujol Tugores 《Revista española de enfermedades digestivas》2004,96(5):322-330
AIM: to investigate the influence of different experimental manipulations in a model of colonic experimental carcinogenesis with pharmacological induction in the rat. EXPERIMENTAL DESIGN: a total of 90 Sprague-Dawley male rats, divided into three groups, were used: non-surgical (n = 30); surgical with colonic trauma (n = 20), and surgical with colo-colonic anastomosis (n = 40). Carcinogenic induction was carried out with 1-2 dimethylhydrazine dihydrochloride. Colonic adenocarcinomas were identified and the number of tumors, as well as tumoral surface and percentage of tumoral surface was established. One-way ANOVA and Chi-square were employed for the statistical analysis. RESULTS: the number of tumors was greater in the surgical group than in the control group, and tumors preferentially developed around the manipulated colon. Surface and tumoral percentage were greater in the surgical group than in the control group, being also greater in the anastomosis group than in the group with colonic trauma. Within anastomosis groups, a greater tumor surface and percentage was found in the group with titanium than in the group with reabsorbable material. CONCLUSIONS: the experimental manipulation of the colon in rats enhances drug-induced colon carcingenesis. The creation of an anastomosis further increases the carcinogenic process compared with simulated anastomosis. This process is also enhanced by the quantity of suture material included in the anastomosis, and by the non-reabsorbable nature of the materials used in the anastomotic line. 相似文献
85.
Lemos PA de Feyter PJ Serruys PW Saia F Arampatzis CA Disco C Mercado N Mainar V Morís C van den Bos AA Berghoefer G 《International journal of cardiology》2005,98(3):479-486
BACKGROUND: To evaluate the impact of the extent of coronary disease (single- or multivessel) and of fluvastatin treatment on the incidence of long-term cardiac atherosclerotic complications in the Lescol Intervention Prevention Study (LIPS). METHODS: A total of 1063 patients with single-vessel disease and 614 patients with multivessel disease were randomized to receive fluvastatin (40 mg bid) or placebo for at least 3 years following a first successful percutaneous coronary intervention. The incidence of cardiac atherosclerotic events (cardiac death, non-fatal myocardial infarction, and coronary re-interventions not related to restenosis) was evaluated. RESULTS: Patients with multivessel disease tended to be older and presented a higher prevalence of associated risk factors and cardiovascular antecedents. The presence of multivessel disease markedly increased the risk of cardiac atherosclerotic events compared with single-vessel disease among patients allocated to placebo (RR 1.67 [95% CI: 1.24-2.25]; p<0.001). In patients treated with fluvastatin, however, no significant differences in long-term outcomes were observed between patients with multivessel disease and patients single-vessel disease (RR 1.28 [95% CI: 0.90-1.81]; p=0.2). CONCLUSIONS: Multivessel coronary disease impaired the 4-year outcomes after percutaneous intervention. However, the hazardous effect of multivessel disease was significantly reduced by long-term fluvastatin treatment. 相似文献
86.
The neural basis of feedback expectation, which is crucial in learning theory, has only been minimally studied. Stimulus‐preceding negativity (SPN), an ERP component that appears prior to the presentation of feedback, has been proposed as being related to feedback expectation. The present study showed, for the first time, amplitude modulations of the SPN component during learning acquisition in a trial‐by‐trial associative learning task. The results indicate that SPN could be a plausible electrophysiological index of the cognitive processes engaged while expecting the appearance of relevant feedback during reinforcement learning. 相似文献
87.
D. Bacigalupe W. Basso S. G. Caspe G. Moré L. Lischinsky M. L. Gos M. Leunda L. Campero D. P. Moore G. Schares C. M. Campero M. C. Venturini 《Parasitology research》2013,112(7):2585-2592
Neospora caninum infection is a major cause of abortion in cattle. The objectives of this study were to genetically characterize the N. caninum NC-6 Argentina isolate using a multilocus microsatellite analysis approach and to study its biological behavior by experimental inoculations into seronegative and seropositive pregnant cattle, evaluating the humoral and cellular immune response elicited and the occurrence of transplacental transmission and fetopathy. Pregnant cows (65 days of gestation) seropositive and seronegative to N. caninum were intravenously inoculated with tachyzoites of the NC-6 Argentina N. caninum strain and slaughtered at 108?±?2 days of gestation. Serum samples were analyzed for N. caninum antibodies by indirect fluorescent antibody test. The cellular immune response was analyzed by detection of gamma interferon (γIFN) production in blood cells. Tissue samples from dams, fetuses, and placental cotyledons were processed by histopathological and immunohistochemical techniques and examined for N. caninum DNA by PCR. Positive DNA samples were further analyzed by multilocus microsatellite typing for N. caninum. Inoculated animals had significantly higher N. caninum antibody titers and γIFN production than control animals. One seropositive inoculated cow aborted, one seronegative cow had a non-viable fetus, and the remaining fetuses from the experimentally inoculated dams had histopathologic lesions. The PCR was positive in 3/4 fetuses from seronegative inoculated cows and in 2/3 fetuses from seropositive inoculated cows. Multilocus microsatellite analysis revealed that the N. caninum DNA present in fetuses and placentas had an identical pattern to NC-6 Argentina strain. The NC-6 Argentina strain proved to be able to cross the placenta and to induce fetopathy in both the seropositive and seronegative dams. 相似文献
88.
The ctpA gene encodes the C-terminal processing protease for the D1 protein of the photosystem II reaction center complex. 总被引:8,自引:0,他引:8
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P R Anbudurai T S Mor I Ohad S V Shestakov H B Pakrasi 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(17):8082-8086
The D1 protein of the photosystem II (PSII) complex in the thylakoid membrane of oxygenic photosynthetic organisms is synthesized as a precursor polypeptide (pD1) with a C-terminal extension. Posttranslational processing of the pD1 protein is essential to establish water oxidation activity of the PSII complex. We have recently identified a gene, ctpA, a mutation in which resulted in a loss of PSII activity in the cyanobacterium Synechocystis sp. PCC 6803. To study the function of the CtpA protein, we inactivated the ctpA gene by inserting a kanamycin-resistance gene into its coding sequence. The resultant mutant strain, T564, had no PSII-mediated water oxidation activity, but it had normal cytochrome b6f and photosystem I activities. Measurements of thermoluminescence profiles and rates of reduction of 2,6-dichlorophenolindophenol indicated that PSII complexes in the mutant cells had functional reaction centers that were unable to accept electrons from water. Immunoblot analysis showed that D1, D2, CP47, CP43, and the alpha subunit of cytochrome b559, five integral membrane proteins of PSII, were present in T564 cells. Interestingly, the D1 protein in the mutant cells was 2 kDa larger than that in wild-type cells, due to the presence of a C-terminal extension. We conclude that the CtpA protein is a processing enzyme that cleaves off the C-terminal extension of the D1 protein. Interestingly, the CtpA protein shows significant sequence similarity to the interphotoreceptor retinoid-binding proteins in the bovine, human, and insect eye systems. 相似文献
89.
Jackob Moskovitz Barbara S. Berlett J. Michael Poston Earl R. Stadtman 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(18):9585-9589
A gene homologous to methionine sulfoxide reductase (msrA) was identified as the predicted ORF (cosmid 9379) in chromosome V of Saccharomyces cerevisiae encoding a protein of 184 amino acids. The corresponding protein has been expressed in Escherichia coli and purified to homogeneity. The recombinant yeast MsrA possessed the same substrate specificity as the other known MsrA enzymes from mammalian and bacterial cells. Interruption of the yeast gene resulted in a null mutant, ΔmsrA::URA3 strain, which totally lost its cellular MsrA activity and was shown to be more sensitive to oxidative stress in comparison to its wild-type parent strain. Furthermore, high levels of free and protein-bound methionine sulfoxide were detected in extracts of msrA mutant cells relative to their wild-type parent cells, under various oxidative stresses. These findings show that MsrA is responsible for the reduction of methionine sulfoxide in vivo as well as in vitro in eukaryotic cells. Also, the results support the proposition that MsrA possess an antioxidant function. The ability of MsrA to repair oxidative damage in vivo may be of singular importance if methionine residues serve as antioxidants. 相似文献
90.