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51.
J D Boice R E Curtis R A Kleinerman J T Flannery J F Fraumeni 《The Yale journal of biology and medicine》1986,59(5):533-545
Recently, the National Cancer Institute published a comprehensive monograph on multiple primary cancers in Connecticut and Denmark. This paper summarizes some of the observations made on the Connecticut population. Data compiled by the Connecticut Tumor Registry have extended our knowledge about the patterns of multiple primary cancers, especially among long-term survivors of cancer and among patients with relatively rare tumors about which little information currently exists. When compared with the general Connecticut population, cancer patients had a 31 percent (RR = 1.31) increased risk of developing a second cancer and a 23 percent (RR = 1.23) elevated risk of second cancer at a different site from the first. Common environmental exposures seemed responsible for the excess occurrence of many second cancers, particularly those related to cigarette smoking, alcohol consumption, or both. For example, persons with epithelial cancers of the lung, larynx, esophagus, buccal cavity, and pharynx were particularly prone to develop new cancers in the same or contiguous tissue throughout their lifetimes. Cancers of the colon, uterine corpus, breast, and ovary frequently occurred together, suggesting underlying hormonal or dietary influences. Only patients with prostate cancer were at significantly low risk for second cancer development; this might be an artifact of case finding, since advanced age at initial diagnosis was generally associated with an underascertainment of second cancers. Radiotherapy may have caused rectal and other cancer among patients with cancers of the female genital tract, and leukemia among patients with uterine corpus cancer. Chemotherapy with alkylating agents probably contributed to the excess of acute nonlymphocytic leukemia following multiple myeloma or cancers of the breast and ovary. Genetic susceptibility seemed to explain some tumor complexes, such as the multiple occurrences of cutaneous melanoma and the excess of bone cancer following retinoblastoma. Research into multiple cancer syndromes should enhance our understanding of carcinogenic factors and mechanisms and the development of strategies for cancer prevention and control. 相似文献
52.
Cloning and structural characterization of a human non-erythroid band 3-like protein. 总被引:15,自引:3,他引:12
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D R Demuth L C Showe M Ballantine A Palumbo P J Fraser L Cioe G Rovera P J Curtis 《The EMBO journal》1986,5(6):1205-1214
53.
Solubilization of the calcium antagonist receptor from rat brain 总被引:7,自引:0,他引:7
[3H]Nitrendipine binds with high affinity to a calcium antagonist receptor in rat brain membranes. At 4 degrees C, treatment with digitonin solubilized the calcium antagonist receptor as a stable complex with [3H]nitrendipine. The nitrendipine concentration that gave a half-maximal amount of the solubilized [3H]nitrendipine-receptor complex was identical to the Kd for specific nitrendipine binding to brain membranes. Nitrendipine dissociated from digitonin-solubilized and membrane-bound receptors with a half-time of 24 to 30 min at 20 degrees C. Verapamil increased and diltiazem decreased the dissociation rate to a similar extent in both preparations indicating that the solubilized receptor contains both the dihydropyridine and diltiazem/verapamil binding sites. Sucrose gradient sedimentation experiments gave a value of S20, omega = 19.2 for the receptor-digitonin complex. The solubilized calcium antagonist receptor binds specifically to wheat germ agglutinin-Sepharose columns consistent with an identification as a glycoprotein. 相似文献
54.
Lynn M. Riddiford Craig R. Roseland Steven Thalberg Anna T. Curtis 《Journal of insect physiology》1983,29(3):281-286
The juvenile hormone antagonist ETB (ethyl-4-2(t-butylcarbonyloxy)-butoxybenzoate) caused formation of precocious larval-pupal intermediates after the 4th (penultimate)-larval instar of the tobacco hornworm, Manduca sexta, when 50 μg were applied to any 3rd stage larvae or to 4th stage larvae within 12 hr after ecdysis. This dose was most effective within 12 hr after ecdysis to the 3rd stage. In the black mutant larval assay for juvenile hormone, ETB had activity, 0.75 μg per larva giving half-maximal score. In vitro ETB acted as a juvenile hormone to prevent the ecdysteroid-induced change in commitment at concentrations above 0.1 μg/ml with an ED50 at 2.8 μg/ml and as a partial juvenile hormone antagonist to 0.1 μg/ml juvenile hormone I at concentrations between 10?3 and 10?2 μg/ml. By contrast, EMD (ethyl-E-3-methyl-2-dodecenoate) had little juvenile hormone-like activity in vitro up to its limits of solubility (100 μg/ml) and exhibited sporadic partial juvenile hormone antagonistic activity in vitro at concentrations between 1 and 100 μg/ml. Since these concentrations were 10–1000 times that of juvenile hormone I in the medium, EMD apparently is not an efficient competitor. 相似文献
55.
Curtis M. Wilson 《Biochemical genetics》1973,9(1):53-62
Ribonuclease activity in the endosperms of 14 corn (Zea mays L.) inbreds ranged from 285 to 1305 units/g fresh weight 50 days after pollination. Activity is low in the inbred M14 and high in the inbred WF9. Hybrid endosperms contain intermediate levels of ribonuclease, and segregation occurs in the F2 generation. The ribonuclease contents of the opaque-2 versions of nine inbred lines ranged from 1288 to 5110 units/g. The floury-2 mutation apparently does not affect ribonuclease content. Two or more genes may be involved in the control of ribonuclease content of developing endosperms.Cooperative investigations of the Plant Science Research Division, Agricultural Research Service, U.S. Department of Agriculture, and the Illinois Agricultural Experiment Station, Urbana, Illinois. 相似文献
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Summary The effects of anhydrous benzoylation were examined in connection with the following protein end-group methods: diazosulfanilic acid — Azure A, the Sakaguchi reaction and a fluorescent variant, the phenanthrequinone fluorescent method for arginine, the Millon reaction, the Morel-Sisley reaction, the mercury orange method, the alloxan and ninhydrinShiff methods, the Dansyl-chloride fluorescent method for lysine, the dimethylaminobenz-aldehydenitrite (DMAB) method for tryptophan, and the acid fluorochrome brilliant sulfoflavin used at pH 2.8 as a stain for basic groups. With all of these methods except the DMAB method for tryptophan, selective blockage of cytoplasmic proteins and staining of nuclei was obtained. With the DMAB reaction, the results were reversed: cytoplasmic staining exceeded nuclear staining after benzoylation. 相似文献
59.
Curtis RW 《Plant physiology》1968,43(1):76-80
Malformin and ethylene stimulate abscission of the primary leaves of Phaseolus aureus Roxb. in the dark, and abscission stimulation by both compounds is inhibited by indeleacetic acid and CO2. Ethylene production by malformin-treated buds is stimulated within 4 hours. and up to 8 days, after treatment. Malformin-induced growth disturbances in P. vulgaris L. and abscission in P. aureus are considered mediated by ethylene. Although root curvatures of Zea mays L. are induced by both malformin and ethylene, and malformin is inhibited by CO2, ethylene production is not stimulated by malformin. A role of ethylene in root curvatures induced by malformin is neither proposed nor disproved. 相似文献
60.
Peter R. Lorenz John Hotchin Aletha S. Markusen Gert B. Orlob Curtis L. Hemenway Douglas S. Hallgren 《Origins of life and evolution of the biosphere》1968,1(1):118-130
Dried suspensions ofPenicillium roqueforti Thom, Coliphage T-1,Bacillus subtilis and tobacco mosaic virus were exposed to space on board the Gemini-IX-A and XII earth satellites and the Agena-VIII space rocket. All micro-organisms tested survived the direct exposure during the Gemini-IX-A experiment. In the Gemini-XII experiment only the T-1 phage survived the direct exposure. The survival was influenced by the suspending medium and depended on the species of the microorganism. After four months of space flight on the Agena-VIII space rocket surviving fractions between 2×10–3 and 1.0 were found in the unopened flight container. However, micro-organisms exposed on the cover of the container during this period were completely inactivated. Shielding against solar ultraviolet radiation during flight resulted in survival of micro-organisms exceeding to that of the transport controls, and the survival was considered complete.Sterile methylcellulose collection surfaces were exposed to space on board the Gemini-IX-A and XII satellites in an attempt to collect viable micro-organisms in space. None of the collection surfaces yielded viable micro-organisms. 相似文献