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Lake chub is a common freshwater cyprinid found throughout Canada and parts of the northern United States. Here we describe 36 novel microsatellite loci, 25 of which are polymorphic, exhibiting between 2 and 17 alleles each, while the remaining 11 loci are monomorphic. Observed and expected heterozygosities for the polymorphic markers ranged from 0.125 to 0.875 and 0.146 to 0.878, respectively. There was no evidence of linkage disequilibrium between any locus pairs, nor was there any evidence of null alleles. There were however, six markers deviating from Hardy–Weinberg Equilibrium, a result we attribute to relatively small sample size.  相似文献   
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Respiratory disorders, including occupational and environmental lung diseases, are prevalent. Physicians are frequently called upon to determine impairment and aid in the assessment of disability caused by these conditions, either as the treating physician or as an independent medical examiner. In this article we reviewed the role of physicians in determining the presence and severity of pulmonary disorders. A comprehensive clinical assessment and appropriate standardized tests, to objectively characterize the severity of impairment, are the key elements of the evaluation. This assessment may also include the physician's opinion regarding causative factors. Finally, disability determination is made by nonclinicians, through administrative means, based on the degree of impairment and a review of circumstances specific to the individual. Knowledge of these components of disability evaluation will help physicians to better serve their patients and supply appropriate data to the adjudicating system.  相似文献   
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OBJECTIVE: Medroxyprogesterone (MP) was used as the progestogen in randomized clinical trials of postmenopausal hormone replacement on cardiovascular risk. To attempt to understand the lack of benefit in these trials, we have examined the effects of MP and two other progestogens, the less androgenic desogestrel (DG) and the more androgenic norethisterone (NE), on cardiovascular risk factors against a background of oestrogen therapy. DESIGN AND MEASUREMENTS: Thirty-four women were treated with conjugated equine oestrogens (CEE) 0.625 mg daily alone for 12 weeks, followed in random order by each of the three progestogens (DG 75 microg, MP 10 mg and NE 1 mg daily) given sequentially for three 12-week cycles while maintaining the same CEE treatment. We measured serum lipoproteins, paraoxonase activity, C-reactive protein (CRP), fibrinogen, fasting glucose and insulin levels at baseline, at the end of the oestrogen-only phase and at the end of each of the combined oestrogen and progestogen phases. RESULTS: The addition of progestogens to CEE maintained the oestrogen-induced reduction in apolipoprotein B (apo B) and lipoprotein (a) [Lp(a)], and further lowered total cholesterol (P < 0.01) and fibrinogen (P < 0.001). CEE raised serum triglyceride (P < 0.001) and CRP (P < 0.01) concentrations, which reverted towards pre-oestrogen levels with progestogens. Progestogens significantly reduced high density lipoprotein (HDL) cholesterol (P < 0.05). NE was associated with the greatest reduction in HDL cholesterol and apo A1, but was most effective in preserving paraoxonase activity and reducing the potentially unfavourable oestrogen-induced increases in triglycerides and CRP. CONCLUSION: Preconceptions that more androgenic progestogens necessarily have more unfavourable effects on cardiovascular risk factors may require revision.  相似文献   
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