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971.
Prostate cancer is the second most common cause of death in men; it is diagnosed in about 1 in 10 men. Significant risk factors include, but are not limited to, race and age; the peak age at diagnosis is the seventh decade. A through screening program, sensitive to the risk factors and targeted to patients with curable prostate cancer, can decrease the rates of mortality and morbidity associated with this disease, without overtreating patients who have latent cancer. Screening methods include annual digital rectal examinations and prostate-specific antigen tests. Staging is important when treatment options are considered and treatment morbidity rate is weighed against disease mortality rate. Research concerning genetics changes and chemoprevention trials of vitamins and hormonal agents are targeted toward primary prevention. Implications for practice should include primary prevention, screening and detection, public education, and monitoring of the disease. 相似文献
972.
ME Sullivan CR Bell MR Dashwood MA Miller CS Thompson DP Mikhailidis RJ Morgan 《Canadian Metallurgical Quarterly》1996,30(4):506-511
OBJECTIVES: To investigate density and distribution of nitric oxide synthase (NOS) binding sites in rat cavernosal tissue, and to assess any changes brought about by the onset of diabetes mellitus. METHODS: Hyperglycaemic non-ketonuric diabetes mellitus was induced in 5 rats using streptozotocin. The penises were excised from these rats 2 months after the administration of streptozotocin and stored at -70 degrees C. Longitudinal serial sections (6 microns) were cut in a cryostat and thaw mounted onto gelantinized microscope slides. Low- and high-resolution autoradiography was performed using a radioligand for NOS. Densitometric analysis was performed on the autoradiographs and the results compared with those obtained from 5 age-matched no-diabetic rats. RESULTS: NOS binding was primarily localized to the endothelium lining the cavernosal lacunar spaces. Significantly increased binding of NOS was seen in the diabetic cavernosal tissue 2 months after induction of diabetes mellitus. CONCLUSIONS: NOS binding is present on the endothelium of the rat corpus cavernosum and is increased in diabetic rats 2 months after streptozotocin administration. This increase in NOS binding may be part of the endothelial dysfunction which is reported in the corpus cavernosum of diabetic patients or rats. 相似文献
973.
PA Flume TM Egan LJ Paradowski FC Detterbeck JT Thompson JR Yankaskas 《Canadian Metallurgical Quarterly》1994,149(6):1601-1607
It has been suggested that the presence of airway pathogens prior to lung transplantation (LT) in patients with cystic fibrosis (CF) may place these patients at a higher risk for infectious complications after LT. There is particular concern regarding patients colonized with multiresistant Pseudomonas, including P. cepacia, and fungi, including Aspergillus. We report our experience with LT for patients with CF and compare the results with those of patients with LT for other indications. Between January 1990 and March 1993, we performed LT for 27 patients with CF and 32 without CF. Nearly all (89%) of the patients with CF were colonized with P. aeruginosa; many were cultured with P. cepacia (19%) and Aspergillus (63%). The non-CF group rarely had organisms identified pre-LT. No patients with CF underwent pre-LT sinus drainage or received pre-LT treatment for Aspergillus. All of the patients received perioperative antibiotics and a standard regimen of immunosuppression and prophylactic antibiotics. The incidence of infectious complications was the same in the two groups; however, there was an association between obliterative bronchiolitis and pulmonary infections. One of the patients with CF with P. cepacia died as a result of this organism. None of the patients with CF required treatment for Aspergillus post-transplant. We conclude that patients with CF, despite the presence of airway pathogens, are at no greater risk of infectious complications after LT than are other patients. 相似文献
974.
Espelage Dorothy L.; Mazzeo Suzanne E.; Aggen Steven H.; Quittner Alexandra L.; Sherman Roberta; Thompson Ron 《Canadian Metallurgical Quarterly》2003,15(1):71
The construct validity of the Eating Disorder Inventory (EDI) was examined in 3 samples. An archival clinic sample (n=318) of women completed the EDI, a structured interview, and the Millon Clinical Multiaxial Inventory--II (MCMI-II). Confirmatory factor analyses (CFAs) indicated that neither null nor 1-factor models of the EDI fit item-level or item-parcel data. The proposed 8-factor model did not fit at the item level but did fit item-parcel data. Reliability estimates of the 8 scales ranged from .82 to .93, and low-to-moderate interscale correlations among the eating and weight-related scales provided partial support for convergent validity. EDI personality scales showed moderate interscale correlations and were associated with MCMI-II scales. A final CFA of the EDI scales supported a 2-factor model (Eating and Weight, Personality) of the 8 EDI scales. Strong associations between depression and several EDI scale scores were found in a treatment study sample (n=50). The archival clinic sample scored significantly higher on the 8 EDI scales than the nonpatient college comparison sample (n=487). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
975.
976.
Six Friesian cows were milked daily, and arterial and mammary venous blood samples were taken between day 266 of gestation and day 6 after parturition. Samples of blood plasma were analysed for their content of acetate and progesterone, and mammary secretion for potassium, isocitrate, 2-oxoglutarate and triglyceride fatty acids. The onset of secretion of medium-chain triglyceride fatty acids was preceded by, or coincided with, increases of potassium and isocitrate concentration in the secretion. The onset of fatty acid secretion was not accompanied by any change in the gland's extraction of acetate from the circulation, and did not occur at a consistent time relative to parturition or changes in plasma progesterone concentration. 相似文献
977.
Ryan W. Dupon Richard L. McConville Douglas J. Musolf Adam C. Tanous Mark S. Thompson 《Journal of the American Ceramic Society》1990,73(2):335-339
Bismuth oxide has been found to be a useful flux for the preparation of dense body cordierite (Mg2 Al4 Si5 O18 ). The addition of as little as 2 at.% of bismuth ion to the appropriate stoichiometric mix of commercially available oxide starting materials gives fully dense cordierite after firing for 12 h at 1000°C. The lower-temperature limit for this reaction is 960°C, with essentially no reaction occurring below this temperature. There is also a temperature-dependent induction period prior to cordierite formation. The microstructure of the sintered body has the residual bismuth oxide flux distributed in discontinuous domains at the grain boundaries and at the triple points. The cordierite body has a dielectric constant of 5.0, unperturbed by the presence of the bismuth oxide. 相似文献
978.
979.
Micromechanistic expressions of continuum microscale parameters for stable crack growth 总被引:1,自引:0,他引:1
Warren M. Garrison Anthony W. Thompson 《Metallurgical and Materials Transactions A》1986,17(12):2249-2253
Expressions are proposed for the continuum microscale parameters used by Rice and co-workers in their treatment of stable
crack growth. Two different approaches were taken. In the first the microscale parameters were expressed in terms of a primary
particle spacing and functions of the fracture strain. In the second they were expressed in terms of the particle spacing
and measures of the extent of void growth. Both approaches suggest that the tearing modulus will be a function of only the
fracture strain and not explicitly a function of the particle spacing. 相似文献
980.
Bcl-2-family proteins: the role of the BH3 domain in apoptosis 总被引:1,自引:0,他引:1
Bcl-2-related proteins have come to occupy a prominent position in the realm of programmed cell death. Members of this fast-growing family are highly related in one or more specific regions, commonly referred to as Bcl-2 homology (BH) domains. BH domains contribute at multiple levels to the function of these proteins in cell death and survival. Particularly intriguing is the emergence of the BH3 domain as a potent 'death domain' and of a growing subclass of pro-apoptotic proteins with no similarity to Bcl-2 beyond their BH3 homology. Here, the authors classify proteins of the Bcl-2 family on the basis of function and domain organization, discuss the importance of the BH3 domain in protein-protein interactions and in cell death and provide possible explanations for the perceived redundancy in the expression of this subclass of death promoters. 相似文献