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21.
Simsek A Celen S Islimye M Danisman N Buyukkagnici U 《Archives of gynecology and obstetrics》2008,278(6):559-563
Objective
We sought to determine whether meconium-stained amniotic fluid is based on chronic hypoxia or not? In case of chronic hypoxia, higher red blood cell (Rbc) count and/or total hemoglobin levels (Hgb) and/or higher fetal hemoglobin (HbF) and/or lower adult hemoglobin (HbA) levels were expected when compared with controls.Design
Case–control study.Setting
Obstetric unit of a tertiary ministry of health hospital.Sample
Fifty singleton pregnancies with meconium-stained amniotic fluid and 50 singleton pregnancies with clear amniotic fluid at all stages of labor.Methods
Umbilical cord blood samples were collected for determination of total blood parameters and hemoglobin electrophoresis.Main outcome measures
Red blood cell count, total hemoglobin, fetal and adult hemoglobin contents (HbF and HbA).Results
Red blood cell count, total hemoglobin, fetal hemoglobin (HbF) and adult hemoglobin (HbA) contents were not different between meconium stained and clear amniotic fluid groups.Conclusion
These results suggest that meconium passage may not be associated with chronic fetal hypoxia as demonstrated by similar red blood cell count, total hemoglobin values and fetal hemoglobin (HbF) and adult hemoglobin (HbA) contents.22.
Bhutta AT 《Seminars in perinatology》2007,31(5):303-308
Ketamine is widely used for anesthesia and analgesia in neonates and children. It provides potent sedation, analgesia, and amnesia, a short duration of action, supporting hemodynamic and respiratory stability. Noncompetitive antagonism of NMDA receptors produces its primary therapeutic effects, but it also alters receptor function at dopaminergic, serotonergic, cholinergic, and opioidergic sites. Recent interest in ketamine stems from its potential to block excitotoxic cell death, although concerns have been raised about anesthetic neurotoxicity in neonatal animal models. The development of ketamine, its clinical profile, toxic effects in the immature brain, and future applications in neonates and children are reviewed in this article. 相似文献
23.
BACKGROUND: Different ovulation trigger methods such as gonadotropin releasing hormone-agonist (GnRH-a) and recombinant human chorionic gonadotropin (r-hCG) plus rescue oocyte retrieval might reveal oocytes in patients with recurrent empty follicle syndrome. CASE: Endogenous luteinizing hormone was triggered with a GnRH-a (Buserelin [Suprefact pro-injection, Aventis-Pharma, Turkey], 250 microg subcutaneously) in a GnRH antagonist (Cetrorelix [Cetrotide 0.25, SeronoTurkey], 0.25 mg/d, starting on day 6), down-regulated cycle. At the first scheduled retrieval, 3 cumulus-oocytecorona complexes were recovered from the left ovary. During chemical denudation with hyaluronidase, 2 of them underwent lysis. The third was a zona-free, germinalvesicle-stage oocyte after mechanical denudation. Oocyte pickup was stopped, and recombinant human chorionic gonadotropin (hCG) (250 microg subcutaneously) was injected. Five cumulus-oocyte-corona complexes were retrieved from the right ovary 24 hours after rescue with recombinant hCG. Only mechanical denudation was done, and 4 zona-free oocytes with germinal vesicle breakdown were seen. All oocytes underwent intracytoplasmic sperm injection, and none of them were fertilized. CONCLUSION: Oocyte maturation defects should be included in etiologic mechanisms for counseling patients with empty follicle syndrome. 相似文献
24.
BackgroundThe past decade has seen a substantial rise in the employment of modern data‐driven methods to study atopic dermatitis (AD)/eczema. The objective of this study is to summarise the past and future of data‐driven AD research, and identify areas in the field that would benefit from the application of these methods.MethodsWe retrieved the publications that applied multivariate statistics (MS), artificial intelligence (AI, including machine learning‐ML), and Bayesian statistics (BS) to AD and eczema research from the SCOPUS database over the last 50 years. We conducted a bibliometric analysis to highlight the publication trends and conceptual knowledge structure of the field, and applied topic modelling to retrieve the key topics in the literature.ResultsFive key themes of data‐driven research on AD and eczema were identified: (1) allergic co‐morbidities, (2) image analysis and classification, (3) disaggregation, (4) quality of life and treatment response, and (5) risk factors and prevalence. ML&AI methods mapped to studies investigating quality of life, prevalence, risk factors, allergic co‐morbidities and disaggregation of AD/eczema, but seldom in studies of therapies. MS was employed evenly between the topics, particularly in studies on risk factors and prevalence. BS was focused on three key topics: treatment, risk factors and allergy. The use of AD or eczema terms was not uniform, with studies applying ML&AI methods using the term eczema more often. Within MS, papers using cluster and factor analysis were often only identified with the term AD. In contrast, those using logistic regression and latent class/transition models were “eczema” papers.ConclusionsResearch areas that could benefit from the application of data‐driven methods include the study of the pathogenesis of the condition and related risk factors, its disaggregation into validated subtypes, and personalised severity management and prognosis. We highlight BS as a new and promising approach in AD and eczema research. 相似文献
25.
David AbiaTrujillo Alejandra Yu LeeMateus Juan C. GarciaSaucedo Omran Saifi Neal M. Patel Felix J. F. Herth John R. Woytanowski Ihab Alshelli Sajive Alevas Juan P. Uribe Becerra Adnan Majid Eric S. Edell Megan M. DuloheryScrodin Janani S. Reisenauer Hiren J. Mehta Michael A. Jantz Hawazin K. Abbas Sebastian FernandezBussy 《The clinical respiratory journal》2022,16(1):43
IntroductionBronchoscopic lung volume reduction (BLVR) with endobronchial valves (EBVs) has emerged as an important treatment method for patients with severe chronic obstructive pulmonary disease (COPD). Acute exacerbations of COPD (AECOPD) are a frequent complication following BLVR with EBV. However, there is no consensus on the prevention of AECOPD.ObjectivesOur study aims to compare the outcomes of different prophylactic measures on the occurrence of AECOPD after BLVR with EBV.MethodsWe conducted a multicenter, retrospective study of patients who underwent BLVR with EBV at six different institutions. Emphasis was directed towards the specific practices aimed at preventing AECOPD: antibiotics, steroids, antibiotics plus steroids, or no prophylaxis. Subgroups were compared, and odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated.ResultsA total of 170 patients were reviewed. The rate of AECOPD was 21.2% for the full cohort. Patients who received prophylaxis had a significantly lower rate of AECOPD compared with those who did not (16.7% vs. 46.2%; p = 0.001). The rate was lowest in patients who received antibiotics alone (9.2%). There was no significant difference in the rate of AECOPD between patients who received steroids alone or antibiotics plus steroids, compared with the other subgroups. The OR for AECOPD was 4.3 (95% CI: 1.8–10.4; p = 0.001) for patients not receiving prophylaxis and 3.9 (95% CI: 1.5–10.1; p = 0.004) for prophylaxis other than antibiotics alone.ConclusionsAdministration of antibiotics after BLVR with EBV was associated with a lower rate of AECOPD. This was not observed with the use of steroids or in combination with antibiotics. 相似文献
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Since the discovery of acid-sensing ion channels in 1997, their importance in the health of neurons and other non-neuronal cells has gained significant importance. Acid-sensing ion channels play important roles in mediating pain sensation during diseases such as stroke, inflammation, arthritis, cancer, and recently migraine. More interestingly, acid-sensing ion channels may explain the sex differences in pain between males and females. Also, the ability of acid-sensing ion channel blockers to exert neuroprotective effects in a number of neurodegenerative diseases has added a new dimension to their therapeutic value. The current failure rate of ~45% of new drugs(due to toxicity issues) and saving of up to 7 years in the life span of drug approval makes drug repurposing a high priority. If acid-sensing ion channels' blockers undergo what is known as "drug repurposing", there is a great potential to bring them as medications with known safety profiles to new patient populations. However, the route of administration remains a big challenge due to their poor penetration of the blood brain and retinal barriers. In this review, the promise of using acid-sensing ion channel blockers as neuroprotective drugs is discussed. 相似文献
30.
Vasodilating mechanisms of testosterone. 总被引:2,自引:0,他引:2
The increased incidence of cardiovascular disease in man compared with premenopausal women suggests an unfavourable effect of male sex hormone testosterone on the cardiovascular system. However, numerous clinical and epidemiological studies reported a controversial relationship between testosterone and cardiovascular disease. Furthermore, an increasing amount of evidence indicate that testosterone can exert acute vasorelaxing effects, VIA non-genomic mechanisms. These effects involve primarily the vascular smooth muscle, without requiring the presence of endothelium, although an endothelial contribution is apparent in some studies. To date, the mechanism behind the vasodilatory action of testosterone is still under debate and might be through either activation of K (+) channels or blockade of Ca (2+) channels in vascular muscle cells. The purpose of this article is to review the evidence regarding the vasodilating effect of testosterone as well as its mechanism of action. 相似文献