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Pertinent ethical and legal issues in the international transaction of donor sperm and eggs are discussed. Firstly, there may be legislative and ethical “contradiction” by the local health authority in permitting import of donor gametes, due to varying policies on donor reimbursement in different countries. This is particularly significant in countries where the underlying principle of gamete donation is altruistic motivation, and where reimbursement is given only for direct “out-of-pocket” expenses i.e. traveling costs. Secondly, there is a lack of clear and coherent internationally-binding legislation and regulatory guidelines overseeing the exchange of donor gametes across international borders. In particular, provisions should be made for donor traceability if gametes are sourced from abroad. Thirdly, in the case of “frozen-egg donation” from abroad, patients must rightfully be informed that current cryopreservation technology is still sub-optimal, and all studies have consistently shown that the chances of conception are always lower with “frozen-eggs” compared to freshly-retrieved eggs. Finally, regulatory safeguards should be put in place to prevent fertility clinics and medical professionals from “re-selling” imported donor gametes at a profit to the patient, since it would be thoroughly unprofessional for them to earn a profit simply through the ‘brokerage’ of donated human material.  相似文献   
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Recent advances in oocyte and ovarian tissue cryopreservation technology have not only brought hope to women facing premature loss of ovarian function; it can also be utilized for healthy women seeking to extend their biological clocks. This is a major issue of contention in healthcare ethics. Proponents of this new technology argue that this enables women to fully pursue educational and career goals in their youth, whilst upon reaching middle age they would have more financial resources for their offspring. Nevertheless, this argument is flawed by the reality that even if the cryopreservation of oocytes and ovarian tissue were optimized, this would in no way be a guaranteed route for women to have biological children later in life. Moreover, because only a limited amount of autologous reproductive material can be cryopreserved and stored for a single healthy woman, there is a risk of material depletion before reproductive success is attained. Another prime consideration is the increased morbidity and mortality associated with clinical assisted reproduction in older women. Hence, it is suggested that the cryopreservation and storage of oocytes and ovarian tissues be restricted only to women facing the prospect of premature ovarian failure.  相似文献   
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This study focused on the encapsulation of vancomycin(VAN) into liposomes coated with a red blood cell membrane with a targeting ligand, daptomycin–polyethylene glycol–1,2-distearoyl-sn-glycero-3-phosphoethanolamine, formed by conjugation of DAPT and Nhydroxysuccinimidyl-polyethylene glycol-1,2-distearoyl-sn-glycero-3-phosphoethanolamine.This formulation is capable of providing controlled and targeted drug delivery to the bacterial cytoplasm. We performed MALDI-TOF, NMR and FTIR analyses to conf...  相似文献   
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BackgroundAsthma and chronic obstructive pulmonary disease (COPD) are airway diseases with similar clinical manifestations, despite differences in pathophysiology. Asthma-COPD overlap (ACO) is a condition characterized by overlapping clinical features of both diseases. There have been few reports regarding the prevalence of ACO in COPD and severe asthma cohorts. ACO is heterogeneous; patients can be classified on the basis of phenotype differences. This study was performed to analyze the prevalence of ACO in COPD and severe asthma cohorts. In addition, this study compared baseline characteristics among ACO patients according to phenotype.MethodsPatients with COPD were prospectively enrolled into the Korean COPD subgroup study (KOCOSS) cohort. Patients with severe asthma were prospectively enrolled into the Korean Severe Asthma Registry (KoSAR). ACO was defined in accordance with the updated Spanish criteria. In the COPD cohort, ACO was defined as bronchodilator response (BDR) ≥ 15% and ≥ 400 mL from baseline or blood eosinophil count (BEC) ≥ 300 cells/μL. In the severe asthma cohort, ACO was defined as age ≥ 35 years, smoking ≥ 10 pack-years, and post-bronchodilator forced expiratory volume in 1 s/forced vital capacity < 0.7. Patients with ACO were divided into four groups according to smoking history (threshold: 20 pack-years) and BEC (threshold: 300 cells/μL).ResultsThe prevalence of ACO significantly differed between the COPD and severe asthma cohorts (19.8% [365/1,839] vs. 12.5% [104/832], respectively; P < 0.001). The percentage of patients in each group was as follows: group A (light smoker with high BEC) – 9.1%; group B (light smoker with low BEC) – 3.7%; group C (moderate to heavy smoker with high BEC) – 73.8%; and group D (moderate to heavy smoker with low BEC) – 13.4%. Moderate to heavy smoker with high BEC group was oldest, and showed weak BDR response. Age, sex, BDR, comorbidities, and medications significantly differed among the four groups.ConclusionThe prevalence of ACO differed between COPD and severe asthma cohorts. ACO patients can be classified into four phenotype groups, such that each phenotype exhibits distinct characteristics.  相似文献   
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