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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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目的 研究大鼠出生后锰接触对黑质多巴胺 (DA)神经元发育的毒性影响。方法 采用Morris水迷宫试验检测仔鼠的肌力变化 ;荧光分光度计法检测仔鼠尾状核脑匀浆DA含量的变化 ;酪氨酸氢氧化酶(TH)免疫细胞化学 (ABC法 )与图象分析相结合法检测黑质DA神经元和尾状核DA纤维的免疫反应强度和平均相对密度。结果  (1)随着染锰浓度的增高 ,仔鼠的肌力呈现明显的衰退 ;(2 )尾状核脑匀浆的DA含量 ,随染锰浓度的升高而降低 ;(3)黑质TH免疫反应阳性神经元和尾状核TH免疫反应阳性纤维的反应强度、以及相应的TH阳性产物的平均相对密度 ,均随着染锰浓度的升高而显著下降。结论 大鼠生后锰接触 ,对黑质多巴胺神经元的发育有明显的毒性损害 ,其损害程度随染锰的剂量升高而增加  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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0引言创伤,特别是交通伤已成为人类一大公害,国外从本世纪40年代开始进行实验研究,早期实验研究无论是用自由落体式或摆锤式致伤撞击装置,不仅体积大且笨重,最大缺点是不能模拟高速致伤条件[‘·’j.随后有人用撞击枪制造动物创伤模型,显提高了撞击速度,机型较小,使用方便,但其速度和压缩幅度不易掌握.本世纪80年代初美国通用汽车公司首先设计制作出气动式撞击机,使撞击速度大大提高.1993年国内第三军医大学野战外科研究所报道在BIM-1型(自由落体式)生物撞击机基础上研制出一台BIM-I型(气动式)生物撞击机「‘’.我…  相似文献   
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Ruxolitinib, a Janus kinase inhibitor, improves symptoms in patients with myelofibrosis. However, its association with the development of opportunistic infections has been a concern. We herein report a 71-year-old man with primary myelofibrosis who developed disseminated tuberculosis and concurrent disseminated cryptococcosis during ruxolitinib treatment. We also reviewed the literature on disseminated tuberculosis and/or cryptococcosis associated with ruxolitinib treatment. This is the first case of disseminated tuberculosis and concurrent disseminated cryptococcosis during treatment with ruxolitinib. We therefore suggest considering not only disseminated tuberculosis but also cryptococcosis in the differential diagnosis of patients with abnormal pulmonary shadows during ruxolitinib treatment.  相似文献   
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