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71.
Ojha RP Hanzis CA Hunter ZR Greenland S Offutt-Powell TN Manning RJ Lewicki M Brodsky PS Ioakimidis L Tripsas CK Patterson CJ Sheehy P Singh KP Treon SP 《Cancer epidemiology》2012,36(3):294-297
BackgroundLittle is known about the epidemiology and etiology of Waldenstrom macroglobulinemia (WM). Despite several studies of the relation between family history and B-cell disorders and WM, family history of non-hematologic cancers has not been systematically investigated. We thus examined associations of family history of breast, colorectal, lung, ovarian, and prostate cancers with WM.MethodsAll probands aged 20–79 years with bone marrow biopsy-confirmed diagnosis of WM between May 1, 1999 and January 1, 2010 at the Bing Center for Waldenstrom Macroglobulinemia were eligible for inclusion in our analysis. We reviewed medical records for eligible probands to determine family history of cancer (defined as a cancer diagnosis for ≥1 first-degree relative(s) of the proband). Using expected values constructed from the United States National Health Interview Survey, we estimated age- and race-standardized rate ratios (RRs) for family history of breast, colorectal, lung, ovarian, and prostate cancers by WM subtype.ResultsFamily history of prostate cancer had the largest overall rate ratio (RR = 1.4, 95% confidence limits [CL]: 1.1, 1.7), and among sporadic cases, family history of prostate and breast cancer had the largest rate ratios (prostate: RR = 1.3, 95% CL: 1.1, 1.7; breast: RR = 1.3, 95% CL: 1.2, 1.6).ConclusionOur study suggests that it may be worthwhile to pursue these associations in a case–control study with uniform selection and data collection for cases and controls, and at least some record-based information on family history. 相似文献
72.
A method of microwave (MW) assisted synthesis was employed to prepare cadmium sulfide (CdS) quantum dots (QDs) in dimethylformamide in the presence of poly(methyl methacrylate) (PMMA). The MW irradiation was carried out for a fixed time of 20-30 s and the size of QDs varied from 2.9-5.5 nm. Before each irradiation the solution was cooled down to ambient temperature and the irradiation process was repeated six times. An increase in the intensity and red shift of the characteristic UV-vis absorption peak originating from CdS QDs were observed with repeated MW irradiation, suggesting that the amount of generated CdS QDs increased within the PMMA network and aggregated with repeated MW irradiation. MW irradiation could influence selectively the nucleation and growing rates of PMMA-CdS QDs systems. The broadness and large Stokes shift of the emission from Cd(2+)-rich PMMA-CdS QDs was due to the surface trap state photoluminescence. The recombination of shallow trapped electrons and shallow trapped holes has been considered as the primary source of the surface trap state photoluminescence in Cd(2+)-rich PMMA-CdS QDs. The photoluminescence lifetime was observed to be decreased sharply when the amount of QDs was less, showing the emission decay was dependent on the surface property of PMMA-CdS QDs. The origin of the longer lifetime was due to the involvement of surface trap states and dependent on the amount of CdS QDs present within PMMA and its environment. The effect of the concentration of Cd(2+), S(2-) and PMMA on the generation of CdS QDs within PMMA and the effect of repeated MW irradiation on the optical properties was studied and the results are discussed in this article. 相似文献
73.
Immunomodulatory effect of laser on whole body exposure. 总被引:2,自引:0,他引:2
L Ganju A Salhan D Karan S Chanda K K Srivastava 《Indian journal of experimental biology》1999,37(5):444-449
All biomedical laser applications are based on the interaction of laser light with biological system. During the past decade considerable evidence has accumulated demonstrating that non-thermal exposure to laser can elicit cellular changes in the immune system. In the present study, we have analyzed the effect of laser on immune response in rats. A group of rats were exposed to 0.225 mu j/cm2 for 90 min for 3 days in specially designed fiberglass chambers. The whole body exposure of rats of He-Ne laser modulated both the humoral and cellular responses to tetanus toxoid stimulation. Plain red light used as a control for red laser light showed an appreciable degree of response as compared to the control groups, but not to the extent of the response to laser. Non-responders turned responders after exposure to laser. There was no response in unimmunized groups when exposed to laser and red light alone. The early and heightened immune response and proliferation of lymphocytes after exposure to laser is suggestive of a complex interaction at the cellular immune response level. 相似文献
74.
R. Parkash A. K. Munjal D. Karan 《Journal of Zoological Systematics and Evolutionary Research》1998,36(3):147-152
Indian geographical populations of Drosophila melanogaster exhibit significant correlation (r 0.95) of allelic frequencies at Est -6 and Adh loci with latitude as well as altitude. Est -6S and AdhF allozymes are well adapted to colder environments while Est -6F and AdhS are warm adapted. The data on allozymic clines match climatic conditions on the Indian subcontinent. On the basis of multiple regression analysis, one major conclusion is that coefficient of variation of temperature ( T CV ) along latitude/altitude accounts for alterations in allelic frequency at the Adh locus while T max and T max explain changes at the Est -6 locus. Thus, climatic conditions lead to thermal selection of allozymes in Indian populations of D. melanogaster . 相似文献
75.
Bist Bhuwan Singh Ghimire Prashant K.C. Nishan Poudel Buddi Sagar Pokheral Chiranjibi Prasad Poudyal Laxman Prasad Wright Wendy Basnet Aarati Pradhan Aavas Shah Karan Bahadur 《Biodiversity and Conservation》2021,30(13):3791-3792
Biodiversity and Conservation - 相似文献
76.
Bacterial resistance to aminoglycosides continues to escalate and is widely recognized as a serious health threat, contributing to interest in understanding the mechanisms of resistance. One important mechanism of streptomycin modification is through ATP dependent O-adenylation, catalyzed by streptomycin adenylyltransferase (SMATase). The aim of this study was to purify the recombinant SMATase by Ni(2+)-IDA-His bind resin column chromatography. Thioredoxin-His6-tagged SMATase fusion protein was produced in a bacterial intracellular expression system mainly in a soluble form. The purified fusion protein showed a single band on SDS-PAGE corresponding to 49 kDa. The recovery of fusion protein was 47% with ninefold purification. The fusion system provided a single step, easy and very rapid purification of SMATase and is suitable for obtaining a highly purified functional protein of interest. The fusion does not affect the functionality of the protein. 相似文献
77.
Karan Kaul 《American journal of botany》1986,73(2):242-245
Callus cultures were established from young vegetative shoots of 15 to 18-year-old white pine trees. The callus has been repeatedly subcultured for 15 months on a modified Murashige and Skoog's medium supplemented with 2 mg/L 6-Benzyladenine and 0.2 mg/L α-Naphthaleneacetic acid. Best callus proliferation occurred when 2 to 4-week-old shoots were used as expiants. Older shoots were heavily contaminated with microorganisms and could be only partially disinfected by heat or chemical treatments. 相似文献
78.
79.
Karan P. Singh Carl M.-S. Lee E. Olusegun George 《Biometrical journal. Biometrische Zeitschrift》1988,30(7):843-850
In the analysis of survival data with parametric models, it is well known that the Weibull model is not suitable for modeling cases where the hazard rate is non-monotonic. For such cases, log-logistic model is frequently used. However, due to the symmetric property of the log-logistic model, it may be poor for the cases where the hazard rate is skewed or heavily tailed. In this paper, we suggest a generalization of the log-logistic model by introducing a shape parameter. This generalized model is then applied to fit the lung cancer data of Prentice (1973). The results seem to improve over those obtained by using the log-logistic model. 相似文献
80.
In this paper, a generalized ratio-cum-product estimator for estimating the ratio (product) of two population means using auxiliary information on two other variables is given of which the estimators by SINGH (1969) and SHAH and SHAH (1978) are particular cases. The estimator is regeneralized when the covariance between two auxiliary variables is known. 相似文献