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After recently meeting with his biological parents, the author--a 29-year-old-married male--learned he had been an hour away from being aborted, being 'saved' only by extraordinary circumstances. In the paper the author reflects upon previous strong pro-choice beliefs and reasserts his commitment to a pro-choice philosophy, integrating his new personal experience. The paper pays particular attention to the biological mother's experience and how her fresh insights have reinforced the author's views on abortion.  相似文献   
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Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.  相似文献   
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BACKGROUND AND OBJECTIVE: The adverse effects of untreated seasonal allergic rhinitis (AR) on performance in the workplace, school, and home are poorly understood. To delineate more clearly the impact and consequences of the disease on performance, the effect of symptomatic AR on vigilance and a wide range of cognitive functions was investigated. METHODS: A battery of automated neuropsychological tests was administered to asymptomatic adult subjects with histories of AR. Subjects were randomized to either a symptomatic or to an asymptomatic group. Subjects in the symptomatic group were exposed to ragweed pollen in a controlled exposure setting until they demonstrated predetermined severities of AR symptoms. Subjects in the asymptomatic group were not exposed to ragweed pollen in the environmental unit and retained a minimum symptom profile. The battery of cognitive measures was re-administered to both groups. RESULTS: AR had major adverse impacts on measures of vigilance. Further, AR adversely affected a broad range of cognitive functions. Specifically, subjects with AR symptoms demonstrated longer response times and decreased efficiency on measures of working memory, psychomotor speed, reasoning/computation, and divided attention as compared with asymptomatic subjects. CONCLUSIONS: In addition to decreased vigilance, AR was associated with decrements in speed and efficiency across several cognitive domains. This is similar to findings in research on medications and medical conditions that cause sedation. Findings may represent a link between AR and poor productivity/personal safety among AR sufferers. This suggests that these results have implications with regard to public health.  相似文献   
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Summary— In the present study we have compared the steady state biopharmaceutic characteristics of four diltiazem once daily controlled release capsules: Mono-Tildiem LP 300® (300 mg), Adizem® XL (300 mg)1, Cardizem® (300 mg) and Dilacor® (240 mg). Sixteen healthy male volunteers (aged 22.9 ± 3.3 years, range 19–31 years) completed an open label, multiple oral dose, randomized, four-period crossover study without a washout period in between. The volunteers received each diltiazem formulation once daily for four days. Trough diltiazem and metabolites plasma concentrations were determined on days 3 and 4. The 24-h plasma concentration-time profiles were assessed after the dose on day 4 of each period. The following steady state pharmacokinetic parameters for diltiazem were calculated: the minimum plasma concentration (cmin), the maximum plasma concentration (cmax), the time to reach that concentration (tmax), the time interval during which the plasma concentration exceeds 50% of cmax (t50), the area under the plasma concentration-time curve (AUC72–96) and the peak-to-trough fluctuation (PTF). For the metabolites of diltiazem, N-mono-desmethyl-diltiazem (NDM) and desacetyldiltiazem (DAD), AUC72–96 (AUCNDM and AUCDAD) and the ratio metabolite/parent compound were calculated. Steady state was achieved on day 3. Except one, all controlled release formulations have satisfactory controlled release properties allowing once daily administration. However, significant (P < 0.05) differences were found between the pharmacokinetic characteristics which do not allow exchange of the various formulations. Concentrations well below 50 ng·mL-1 in the morning hours were observed for Dilacor® (240 mg) and Adizem® XL (300 mg), which could be a disadvantage of these formulations as it is well-known that ischaemic events occur at a higher rate during that part of the day. The plasma concentration profiles of NDM and DAD, the major circulating metabolites, parallel the plasma concentration profiles for the parent compound. From a clinical point of view, all treatments were well tolerated.  相似文献   
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