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11.
Summary Pericentric inversion of chromosome 19 has been found in several members of three unrelated families from a restricted geographical region. In one of the families, an additional pericentric inversion of chromosome 9 was observed. Reproductive problems, multiple abortions in two families and a neonatal death in the third, were present. A review of previously described cases is included, and the genetic risk connected with this type of rearrangement is also discussed.  相似文献   
12.
Self-management of insulin-dependent diabetes mellitus (IDDM) is dependent on a negative feedback loop of blood glucose (BG) fluctuations, which in turn directs treatment decisions to maintain normal BG. Although this feedback is typically accomplished by self-monitoring of blood glucose (SMBG), SMBG has limitations, and patients often rely on what their BG "feels" like. Two studies were performed to evaluate whether patients could learn to more accurately "feel"/discriminate their BG on the basis of internal cues or internal plus external BG cues. In Study I, BG Awareness Training significantly improved pre- to posttreatment BG estimation accuracy, relative to a control group. Study II replicated BG Awareness Training efficacy in improving BG estimation accuracy. Improvement in estimation accuracy was related only to initial accuracy; those who were initially less accurate improved the most. This improvement was represented in a 31% reduction in dangerous BG estimation errors and a 9% increase in accurate estimates. Resulting estimations were, however, still significantly less accurate than SMBG at the end of training.  相似文献   
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Self-management of insulin-dependent diabetes mellitus (IDDM) is dependent on a negative feedback loop of blood glucose (BG) fluctuations, which in turn directs treatment decisions to maintain normal BG. Although this feedback is typically accomplished by self-monitoring of blood glucose (SMBG), SMBG has limitations, and patients often rely on what their BG feels like. Two studies were performed to evaluate whether patients could learn to more accurately feel/discriminate their BG on the basis of internal cues or internal plus external BG cues. In Study I, BG Awareness Training significantly improved pre- to posttreatment BG estimation accuracy, relative to a control group. Study II replicated BG Awareness Training efficacy in improving BG estimation accuracy. Improvement in estimation accuracy was related only to initial accuracy; those who were initially less accurate improved the most. This improvement was represented in a 31% reduction in dangerous BG estimation errors and a 9% increase in accurate estimates. Resulting estimations were, however, still significantly less accurate than SMBG at the end of training.This research was supported by NIH grants AM282880, AM24177, AM22125, and RR00847 and by the Ames Company. The authors express their appreciation for the contribution made by trainers Leslie Butterfield and Linda Zimbelman, by the nursing staff at the University of Virginia's Clinical Research Center and the Diabetes and Nutrition Unit, and by Dr. James May from the Medical College of Virginia in soliciting subjects. We would also like to thank Andrea Snyder for her assistance.  相似文献   
15.
Abstract Pseudomonas sp. strain RW611 utilized the ammonium salt of 2-sulfobenzoate as sole source of carbon, sulfur, nitrogen, and energy. The xenobiotic sulfo substituent was dioxygenolytically eliminated as sulfite, which was then slowly oxidized to sulfate. 2,3-Dihydroxybenzoate, which resulted from desulfonation underwent meta -cleavage, mediated by 2,3-dihydroxybenzoate 3,4-dioxygenase activity. This enzyme was inhibited by 3-chlorocatechol and 2,3,4-trihydroxybenzoate.  相似文献   
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A patient with Philadelphia-chromosome positive chronic myelogenous leukemia developed interferon antibodies on treatment with recombinant interferon alpha-2b. Clinically this event corresponded with progressive disease. No cross-reactivity of antibodies with human leukocyte interferon was found by Western blot. Treatment was switched to human leukocyte interferon with an obvious clinical effect: WBC was reduced and platelet count stabilized, but the effect was transient and no hematologic remission was achieved. Human leukocyte interferon may be an alternative in CML-patients with neutralizing antibodies to recombinant interferon alpha.  相似文献   
18.
When CCl4 was incubated with rat liver microsomes from phenobarbital-treated rats in an aerobic or anaerobic atmosphere, over 69% of the heme moiety of cytochrome P-450 was destroyed. At least 45% of the degraded heme under both reaction conditions was accounted for as heme-derived products irreversibly bound to microsomal proteins. Furthermore, 33% of the irreversibly bound products were bound specifically to a 54-kDa form of cytochrome P-450. A structurally different compound, 2-isopropyl-4-pentenamide, also destroyed the heme moiety of cytochrome P-450 and produced heme-derived adducts of microsomal proteins that accounted for 28% of the destroyed heme. These results represent a novel mechanism for the destruction of cytochromes P-450 by xenobiotics.  相似文献   
19.
Externally imposed sinusoidal electric and magnetic fields acting ninety degrees out of phase and perpendicular to each other produce a unidirectional force on an object. The electromagnetic body force arising is found to be proportional to the frequency, to the field strengths, and to the (differential) polarizability of the body acted upon in its medium. The force is found to be small for practically realizable fields, but is different from that of the familiar light pressure. This crossed field force, based as it is upon the frequency-dependent relative effective dielectric constant and loss factor of the body as it moves in the supporting fluid medium, can provice spectra of various dielectric response mechanisms.  相似文献   
20.
Three methods of comparing the vitility of baker's yeast (Saccharomyces cerevisiae) were examined, and found to correlated well. The rate of dough-raising, the degree of visible staining by a reducible dye (methylene blue), and the rate of dielectrophoretic collection as the cells were subject to a nonuniform ac field all appear to agree well as indices of cell viability. The simplicity of the dielectrophoretic technique suggests its further use in cellular assays.  相似文献   
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