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A J Peters C B Coulam 《American journal of reproductive immunology (New York, N.Y. : 1989)》1992,27(3-4):156-162
Anti-sperm antibodies (ASA) occur in 1% to 30% of infertile couples. Mechanisms by which ASA impair fertility include prevention of fertilization by decreasing acrosome reaction and/or zona pellucida binding, and postfertilization effects. Treatment for ASA involves assisted reproductive technologies. 相似文献
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Objective. To provide national estimates of the effect of out-of-pocket premiums and benefits on Medicare beneficiaries' choice among managed care health plans.
Data Sources/Study Setting. The data represent the population of all Medicare+Choice (M+C) plans offered to Medicare beneficiaries in the United States in 1999.
Study Design. The dependent variable is the log of the ratio of the market share of the j th health plan to the lowest cost plan in the beneficiary's county of residence. The explanatory variables are measures of premiums and benefits in the j th health plan relative to the premiums and benefits in the lowest cost plan.
Data Collection Methods. The data are from the 1999 Medicare Compare database, and M+C enrollment data from the Centers for Medicare and Medicaid Services (CMS).
Principal Findings. A $10 increase in an M+C plan's out-of-pocket premium, relative to its competitors, is associated with a decrease of four percentage points in the j th plan's market share (i.e., from 25 to 21 percent), holding the premiums of competing plans constant.
Conclusions. Although our price elasticity estimates are low, the market share losses associated with small changes in a health plan's premium, relative to its competitors, may be sufficient to discipline premiums in a competitive market. Bidding behavior by plans in the Medicare Competitive Pricing Demonstration supports this conclusion. 相似文献
Data Sources/Study Setting. The data represent the population of all Medicare+Choice (M+C) plans offered to Medicare beneficiaries in the United States in 1999.
Study Design. The dependent variable is the log of the ratio of the market share of the j th health plan to the lowest cost plan in the beneficiary's county of residence. The explanatory variables are measures of premiums and benefits in the j th health plan relative to the premiums and benefits in the lowest cost plan.
Data Collection Methods. The data are from the 1999 Medicare Compare database, and M+C enrollment data from the Centers for Medicare and Medicaid Services (CMS).
Principal Findings. A $10 increase in an M+C plan's out-of-pocket premium, relative to its competitors, is associated with a decrease of four percentage points in the j th plan's market share (i.e., from 25 to 21 percent), holding the premiums of competing plans constant.
Conclusions. Although our price elasticity estimates are low, the market share losses associated with small changes in a health plan's premium, relative to its competitors, may be sufficient to discipline premiums in a competitive market. Bidding behavior by plans in the Medicare Competitive Pricing Demonstration supports this conclusion. 相似文献
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Sequence Analysis of the RNA Polymerase Gene of Foot-and-Mouth Disease Virus Serotype Asia1 总被引:1,自引:0,他引:1
George M Venkataramanan R Pattnaik B Sanyal A Gurumurthy CB Hemadri D Tosh C 《Virus genes》2001,22(1):21-26
The complete nucleotide (nt.) sequence of the RNA polymerase (3D) gene and 81 nt. in the 3-untranslated region of foot-and-mouth disease virus (FMDV) serotype Asia1 (IND63/72) was determined and compared with the sequence of other FMDV serotypes. The 3D genomic region was 1410 nt. long encoding 470 amino acids with an inframe stop codon (TAA) at nt. position 1411–1413. The deduced amino acid sequence of the protein showed 8 conserved motifs as reported in other picornaviruses, 2 of which are 100% identical across the serotypes. Antigenic regions in the polymerase protein were predicted and found to be located at the N-terminus of the protein. The phylogenetic analysis showed that the FMD viruses were segregated into different clusters based on geographical origin; the Asia1 virus did not cluster tightly with any of the geographical groups. 相似文献