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DM Bell MA Fair DM Elnicki AK Halperin HC Palmer AC Jain 《Canadian Metallurgical Quarterly》1998,91(11):1042-1046
BACKGROUND: Prevalence of risk factors in patients having myocardial infarction (MI) have been reported in large US and international studies, but little is known about the prevalence of risk factors in West Virginians having MI. METHODS: Risk factors for MI were identified by ICD-9 codes. Logistic regression analysis was used to compute odds ratios and 95% confidence intervals. RESULTS: In this cohort (n = 727), 72% of men less than 65 years old were current smokers. Women were older and had a lower frequency of smoking and a higher frequency of diabetes mellitus and obesity than men. Women less than 65 years old had significantly more hypertension than men. CONCLUSIONS: In West Virginia, women who have MI are more likely to be nonsmoking diabetics with hypertension. 相似文献
134.
A network defect model suitable for use in process simulation is presented for the diffusion of B in SiO2 and, in particular, B in the presence of F and H2. We find that B diffuses via a peroxy linkage defect the concentration in the oxide of which changes under different processing conditions. From random walk theory it is possible then to calculate the resulting diffusion coefficients. These results are compared with measured diffusivities and empirical adjustments are made 相似文献
135.
Wyman D.R. Wilson B.C. Malone D.E. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1992,80(6):890-902
It is noted that both abdominal ultrasound imaging and magnetic resonance (MR) imaging of the brain can produce high contrast images of ILP (interstitial laser photocoagulation) lesions in real or near-real time, during and after ILP. These images provide feedback data that can be used to control dynamically the shape of the ILP lesion. Image-based feedback control of ILP requires that contrast boundaries in images acquired during or immediately after ILP (acute images) correlate with the volumes of irreversibly damaged tissue that result several days later (chronic lesion). An image-to-actual function (IAF) is developed as a transformation that relates acute lesion images to resulting chronic lesions. Algorithms for controlling ILP based on the IAF are presented for control by both human operator (open loop) and computer (closed loop). Preliminary studies indicate that MR image-based control of ILP in the brain should be possible using both open and closed loops. Unreliable IAFs may limit ultrasound image-based control of ILP in abdominal tumors to control based on images acquired a few minutes after stopping the irradiation 相似文献
136.
The tradeoffs between implant damage annealing and shallow junction formation are investigated. For very-low-energy amorphizing implants the time for damage anneal has a fourth-power dependence on depth below the Si surface. The depth effect depends on the type of amorphizing ion. It is shown that as a result, implanted B in Ge-preamorphized Si diffuses with no detectable self-interstitial supersaturation if the damage is <600 Å deep. Conditions for forming defect-free, shallow p+-n junctions are described in design curves and comparisons are made between several junction-formation approaches. Implantation of B at energies below 2 keV offers an attractive way of achieving 500-Å junctions 相似文献
137.
Adenocarcinoma of the prostate is the second leading cause of cancer deaths in men. The protein kinase C (PKC) family of signal transducing kinases has been implicated in neoplastic transformation and progression in other tissues, and some evidence suggests roles for PKC in prostate growth and neoplasia. We have detected expression of eight specific PKC isozyme mRNAs (alpha, beta, gamma, delta, epsilon, eta, theta, and zeta) in normal rat whole prostate and found some of these to be differentially expressed in certain Dunning R-3327 rat prostatic adenocarcinoma sublines. PKC zeta mRNA was detected in normal prostate and Dunning H tumor, whereas an alternatively spliced form of PKC zeta RNA was found in Dunning G tumor and normal brain. Both forms of PKC zeta RNA were markedly reduced in the androgen insensitive, highly metastatic Dunning AT-3, MAT-Lu, and MAT-LyLu tumors. We have cloned and report the sequence of the novel portion of the alternatively spliced form of PKC zeta RNA, which is polyadenylated and present in cytoplasm. 相似文献
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139.
The use of a jet injection instrument was particularly helpful in the anesthetic preparation of biopsy sites selected for tissue culturing of skin and did not lessen culturing success. 相似文献
140.
Secondary ion mass spectrometry has been employed to reveal the gettering of implanted B by an annealed, implanted Sb layer. It is shown that the gettering of B is significant, and may be caused by electric-field-enhanced diffusion of the B as well as by solubility enhancement of the electrically-active Sb. These results emphasize the first-order importance of cooperative effects between donors and acceptors in diffusion profile calculations. 相似文献