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61.
Proton pump inhibitors are used to treat gastroesophageal reflux, a symptom common in pregnancy. The aim of this study was to systematically analyze the available data on the risk for malformations following use of these agents in the first trimester of pregnancy. Medline, EMBASE, published abstracts, and reference lists were searched for articles reporting on proton pump inhibitor use in pregnancy. Summary relative risks and 95% confidence intervals (95% CI) were calculated using the Mantel-Haenszel method. Five cohort studies met the inclusion criteria for this meta-analysis. With almost 600 exposed pregnancies, the overall relative risk was 1.18 with a 95%CI of 0.72–1.94. In conclusion, proton pump inhibitors do not present a major teratogenic risk when used in recommend doses. These data are reassuring for the countless patients who have used these agents in the early part of their pregnancies.  相似文献   
62.
To characterize beta-receptors which affect pancreatic A-cell activity, the effects of propranolol (beta non-selective blockade) and metoprolol (beta 1 selective blockade) were evaluated on epinephrine modulated insulin (IRI) and glucagon (IRG) release both in basal state and during metabolic stimulus (arginine 20 mM). The isolated perfused rat pancreas model with the exclusion of stomach and duodenum was used. Epinephrine infusion (at 10(-7) M) caused a prompt and sustained increase in basal IRG secretion and significantly potentiated glucagon release in response to metabolic stimulus. Insulin secretion was markedly suppressed by epinephrine both in basal conditions and during metabolic stimulus. Propranolol (at 10(-7) M) and metoprolol (at 10(-7) M) infusion clearly and similarly counteracted epinephrine stimulatory effects on IRG secretion but failed to elicit any significant effect on the epinephrine inhibited IRI release either in basal state or during the metabolic stimulus. These results suggest that, at least in the rat, the adrenergic stimulation of IRG release is mediated through a beta 1 receptor.  相似文献   
63.
We determined the biological activity of serum LH in 23 men, aged 25-50 yr, complaining of nonorganic impotence of at least 1-yr duration and 20 normal men. All of the impotent men had normal general physical examinations, penile Doppler tests, psychological tests, and peripheral nerve conduction. Serum PRL, FSH, LH, and thyroid hormone concentrations were normal as were the results of provocative tests of TSH, gonadotropin, and PRL secretion. The mean serum immunoreactive LH (I-LH) levels, measured in each impotent and normal man in three samples taken at 15-min intervals, were similar [7.2 +/- 0.5 (+/-SE) vs. 6.4 +/- 0.5 mIU/mL (IU/L)]. In contrast, the mean serum bioactive LH (B-LH) level was significantly lower in the impotent men than in the normal men [15.9 +/- 2.1 (+/-SE) vs. 33.0 +/- 2.8 mIU/mL (IU/L); P less than 0.05], as was the LH bio- to immunoactive (B/I) ratio (2.1 +/- 0.2 vs. 5.6 +/- 0.5; P less than 0.02). The mean serum testosterone level in the impotent men, although all individual values were within the range of normal for our laboratory [200-900 ng/100 mL (693-3120 nmol/L)], was 25% lower than that in the normal men [347 +/- 23 vs. 450 +/- 26 ng/100 mL; P less than 0.05 (1204 +/- 81 vs. 1560 +/- 91 nmol/L)]. In addition, a significant positive correlation was found between serum testosterone levels and LH B/I ratios in the impotent men (r = 0.45; P = 0.029). Pulsatile LH secretion, measured in six impotent and four normal men in blood samples collected every 15 min for 6 h, was similar in the two groups. The mean serum I-LH levels were similar [7.5 +/- 1.1 (+/-SE) vs. 5.1 +/- 1.0 mIU/mL (IU/L)], while the mean serum B-LH level as well as the LH B/I ratio was significantly lower in the impotent men throughout the observation period [11.4 +/- 2.0 (+/-SE) vs. 26.0 +/- 3.2 mIU/mL (IU/L) and 1.4 +/- 0.2 vs. 5.4 +/- 0.6; P less than 0.05 and P less than 0.02, respectively]. The B-LH pulse amplitude in the impotent men was reduced [mean peak LH, 8.6 +/- 0.3 vs. 25.3 +/- 4.0 mIU/mL (IU/L); P less than 0.05], while the LH pulse frequency was similar in the two groups. The median intrapulse LH B/I ratios were significantly higher than the median interpulse ratios in both impotent (P = 0.02) and normal men (P = 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
64.
Background There is great debate on the possible adverse interaction between proton pump inhibitors (PPIs) and clopidogrel. In addition, whether the use of PPIs affects the clinical efficacy of ticagrelor remains less known. We aimed to determine the impact of concomitant administration of PPIs and clopidogrel or ticagrelor on clinical outcomes in patients with acute coronary syndrome (ACS) after percutaneous coronary intervention (PCI). Methods We retrospectively analyzed data from a “real world”, international, multi-center registry between 2003 and 2014 (n = 15,401) and assessed the impact of concomitant administration of PPIs and clopidogrel or ticagrelor on 1-year composite primary endpoint (all-cause death, re-infarction, or severe bleeding) in patients with ACS after PCI. Results Of 9,429 patients in the final cohort, 54.8% (n = 5165) was prescribed a PPI at discharge. Patients receiving a PPI were older, more often female, and were more likely to have comorbidities. No association was observed between PPI use and the primary endpoint for patients receiving clopidogrel (adjusted HR: 1.036; 95% CI: 0.903–1.189) or ticagrelor (adjusted HR: 2.320; 95% CI: 0.875–6.151) (Pinteraction = 0.2004). Similarly, use of a PPI was not associated with increased risk of all-cause death, re-infarction, or a decreased risk of severe bleeding for patients treated with either clopidogrel or ticagrelor. Conclusions In patients with ACS following PCI, concomitant use of PPIs was not associated with increased risk of adverse outcomes in patients receiving either clopidogrel or ticagrelor. Our findings indicate it is reasonable to use a PPI in combination with clopidogrel or ticagrelor, especially in patients with a higher risk of gastrointestinal bleeding.  相似文献   
65.
Neither the structure nor the function of alpha-bungarotoxin (alpha Bgtx) binding molecules in the nervous system have yet been completely defined, although it is known that some of these molecules are related to cation channels and some are not. Using an improved method of affinity chromatography, we have isolated a toxin binding molecule from chicken optic lobe that contains at least three subunits with apparent Mr values of 52,000, 57,000, and 67,000. The Mr 57,000 subunit binds alpha Bgtx and seems to be present in two copies per receptor. The receptor is recognized by antibodies raised against the alpha Bgtx receptors of human neuroblastoma cells, fetal calf muscle, and chicken optic lobe but not by antibodies raised against Torpedo acetylcholine receptor, the serum of myasthenic patients, or monoclonal antibody, 35. 125I-labeled alpha Bgtx binding to the isolated receptor is blocked, with the same potency, by nicotinic agonists and antagonists, such as nicotine, neuronal bungarotoxin and, d-tubocurarine. When reconstituted in a planar lipid bilayer, the purified alpha Bgtx receptor forms cationic channels with a conductance of 50 pS. These channels are activated in a dose-dependent manner by carbamylcholine and blocked by d-tubocurarine.  相似文献   
66.

Background

Suboptimal vitamin B status might affect cognitive performance in early childhood. We tested the hypothesis that short-term supplementation with folic acid and selected B vitamins improves cognitive function in healthy children in a population with relatively low folate status.

Methods

We screened 1,002 kindergarten children for suboptimal folate status by assessing the total urinary para-aminobenzoylglutamate excretion. Two hundred and fifty low ranking subjects were recruited into a double blind, randomized, controlled trial to receive daily a sachet containing 220 μg folic acid, 1.1 mg vitamin B2, 0.73 mg B6, 1.2 μg B12 and 130 mg calcium, or calcium only for 3 months. Primary outcomes were changes in verbal IQ, short-term memory and processing speed between baseline and study end. Secondary outcomes were urinary markers of folate and vitamin B12 status, acetyl-para-aminobenzoylglutamate and methylmalonic acid, respectively, and, in a subgroup of 120 participants, blood folate and plasma homocysteine.

Results

Pre- and post-intervention cognitive measurements were completed by 115 children in the intervention and 122 in the control group. Compared to control, median blood folate increased by about 50 % (P for difference, P < 0.0001). Homocysteine decreased by 1.1 μmol/L compared to baseline, no change was seen in the control group (P for difference P < 0.0001) and acetyl-para-aminobenzoylglutamate was 4 nmol/mmol higher compared to control at the end of the intervention (P < 0.0001). We found no relevant differences between the groups for the cognitive measures.

Conclusion

Short-term improvement of folate and homocysteine status in healthy children does not appear to affect cognitive performance.  相似文献   
67.
Recovery after Traumatic Brain Injury (TBI) is variable, even for patients with similar severity of brain injury. Recent research has highlighted the contribution that genetic predisposition plays in determining TBI outcome. This review considers the potential for genetic polymorphisms to influence recovery of cognitive and social processes following TBI. Limitations and considerations that researchers should make when assessing the potential impact of polymorphisms on TBI outcome are also discussed. Understanding the genetic factors that support neuroplasticity will contribute to an understanding of the variation in outcome following injury and help to identify potential targets for rehabilitation.  相似文献   
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70.
European Journal of Nuclear Medicine and Molecular Imaging - To compare the incremental diagnostic value of amyloid-PET and CSF (Aβ42, tau, and phospho-tau) in AD diagnosis in patients with...  相似文献   
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