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171.
As of January 1997, 34 states were enforcing restrictions on Medicaid funding for abortions. Determining whether these restrictions affect women's reproductive decisions was the object of a fixed-effects log-linear analysis using 11 years of data between 1978 and 1992. Results indicate that abortion rates in states with Medicaid funding restrictions are 2% lower than rates in states with no such restrictions. However, when the supply of abortion providers and the demographic characteristics of the state population are taken into account, the difference is no longer statistically significant. Medicaid funding restrictions have no impact on birthrates, and the result is the same regardless of whether the empirical model takes into account provider availability, demographic characteristics and state sentiment toward women and reproductive rights. 相似文献
172.
173.
Hameroff S.R. Dayhoff J.E. Lahoz-Beltra R. Samsonovich A.V. Rasmussen S. 《Computer》1992,25(11):30-39
The structure and conformational dynamic changes that occur in cytoskeletal proteins within living cells and evidence for their participation in computational processing are described. The role of cellular automata, in which lattice subunits with discrete states interact only with nearest neighbors, in molecular computing is discussed. Simple rules governing subunit neighbor interactions can lead to complex behaviour capable of computation. It is shown that cellular automata may be implemented in the conformational relationships among neighboring protein subunits of cytoskeletal polymers including microtubules, and microtubule conformational automata networks may signal, adapt, recognize, and subserve neural-level learning 相似文献
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175.
In this letter we present a simplified proof for the convergence of the windowed Cholesky factorization of the time-varying asynchronous code-division multiple-access (CDMA) channel 相似文献
176.
T Shimada K El-Bayoumy P Upadhyaya TR Sutter FP Guengerich H Yamazaki 《Canadian Metallurgical Quarterly》1997,57(21):4757-4764
The effects of synthetic chemopreventive organoselenium compounds 1,2-, 1,3-, and 1,4-phenylenebis(methylene)selenocyanate (o-, m-, and p-XSC, respectively), benzyl selenocyanate (BSC), and dibenzyl diselenide (DDS) and inorganic sodium selenite on the oxidation of xenobiotics and procarcinogens by human cytochrome P450 (P450 or CYP) enzymes were determined in vitro. Spectral studies showed that BSC and three XSC compounds (but not sodium selenite or DDS) induced type II difference spectrum when added to the suspension of liver microsomes isolated from beta-naphthoflavone-treated rats, with m-XSC being the most potent in inducing spectral interactions with P450 enzymes; m-XSC also produced a type II spectral change with human liver microsomes. o-, m-, and p-XSC inhibited 7-ethoxyresorufin O-deethylation catalyzed by human liver microsomes when added at concentrations below 1 microM levels, but BSC and DDS were less effective. All of these compounds inhibited the oxidation of model substrates for human P450s to varying extents. We studied the effects of these compounds on the activation of procarcinogens by recombinant human CYP1A1, 1A2, and 1B1 enzymes using Salmonella typhimurium NM2009 tester strain for the detection of DNA damage. The three XSCs were found to be very potent inhibitors of metabolic activation of 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole, 2-amino-3,5-dimethylimidazo[4,5-f]quinoline, and 2-aminoanthracene, catalyzed by CYP1A1, 1A2, and 1B1, respectively. The potency of inhibition of m-XSC on CYP1B1-dependent activation of 2-aminoanthracene was compatible to those of alpha-naphthoflavone. These inhibitory actions may, in part, account for the mechanisms responsible for cancer prevention by organoselenium compounds in laboratory animals. 相似文献
177.
We sought to estimate the impact of maternal HIV testing and prenatal care on the potential to reduce vertical transmission through zidovudine (AZT) use by HIV-infected mothers. We evaluated the prepartum maternal HIV diagnosis rate, prenatal care, disease stage, and vertical transmission rate (from a two-part mixture model) using New York State Medicaid and vital statistics data for HIV-infected mothers and their singletons in 1985-90. We used published data to estimate the effect of AZT on vertical transmission and expert input to define other parameters for the model. Our HIV-infected (N = 1514) had a vertical transmission rate of 27.0%. HIV was diagnosed prepartum for 39.5% of women in 1990. Transmission would have been 22.2% if AZT had been taken only by the subset of women diagnosed prepartum with HIV and receiving prenatal care by 34 weeks gestation (86.7%). Transmission would have dropped to 11.2% if all women had been diagnosed prepartum with HIV and received adequate prenatal care. The observed deficiencies in prenatal care and maternal HIV diagnosis rates in this Medicaid population-based cohort must be addressed to realize the promise of AZT to reduce vertical transmission. 相似文献
178.
B Malgrange JM Rigo PP Lefebvre P Coucke F Goffin G Xhauflaire S Belachew TR Van de Water G Moonen 《Canadian Metallurgical Quarterly》1997,8(3):591-596
Using dissociated spiral ganglion cell cultures obtained from 3-day-old rat cochlea, we investigated the response of auditory neurones to gamma-aminobutyric acid (GABA) using patch-clamp techniques. In our recording conditions, GABA elicited inward currents in > 95% of the neurones which reversed around 0 mV. Similar inward currents were measured using isoguvacin, a specific agonist of GABAA receptors. GABA-gated currents were reversibly inhibited by the channel blocker picrotoxin and the GABA competitive antagonist bicuculline. These functional GABAA receptors are characterized by an insensitivity to benzodiazepines and a relatively high sensitivity to beta-carbolines and barbiturates. These results show that the GABAA receptor pharmacological properties of spiral ganglion neurones are close to those of cerebellar granule cells. 相似文献
179.
180.