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991.
目的 探讨玻璃化冷冻对卵巢刺激(ovarian stimulation,OS)和控制性超促排卵(controlled ovarian hyperstimulation,COH)来源的卵母细胞影响.方法 对OS和COH来源的卵母细胞进行玻璃化冷冻,解冻后观察存活率,继续发育潜能及移植后的妊娠率并与COH来源的新鲜卵母细胞进行比较.结果 OS和COH来源的卵母细胞玻璃化冻融后的存活率和继续发育潜能无统计学差异(P>0.05),与新鲜卵母细胞差异无统计学意义(P>0.05).COH冷冻组和OS冷冻组的妊娠率和种植率分别是25.0%(3/12)、20.8%(5/24)和33.3%(1/3)、12.5%(1/8).结论 玻璃化冷冻技术可以应用于OS和COH来源的成熟卵母细胞的冷冻保存,对其继续发育潜能和妊娠结局无显著影响. 相似文献
992.
肿瘤的多药耐药(MDR)是导致癌症复发和转移的重要因素。ATP结合盒转运蛋白(ABC转运蛋白)在人体广泛存在,并且ABC转运蛋白的过度表达是导致肿瘤细胞产生MDR的主要原因之一。利用分子影像技术对MDR肿瘤进行早期监测,有利于临床医师制定有效的治疗方案,并在一定程度上能改善肿瘤患者的预后。笔者就分子影像技术在监测MDR方面的研究进展进行简要综述。 相似文献
993.
目的 应用3D打印支架联合人造金刚石探头测量施源器材料对高剂量率后装192Ir源水中吸收剂量的影响。方法 将金刚石探头与塑料插植针分别固定在3D打印支架上,金刚石探头的中心轴与塑料插植针的中心轴在一个平面内相互垂直。采用模拟源尺测量实测驻留位置为248 mm,该驻留位置与逐点测量的最大响应位置吻合。测量材料有304不锈钢、聚亚苯基砜树脂(PPSU)材料、有机玻璃(PMMA)材料和3D打印聚乳酸(PLA)材质。测量水中不同厚度或不同填充率的材料对吸收剂量的衰减。结果 304不锈钢和PPSU材料厚度与相对剂量的线性拟合公式分别为y=-0.029 7x+1.000 3,y=-0.002 3x+1.010 2;拟合优度R2分别为0.925 3和0.722 2。10 mm以内PMMA材料对剂量的影响均<1.5%。3D打印材料填充率(%)与相对剂量的线性拟合公式为y=-0.000 4x+1.024 6,拟合优度R2为0.854 5。结论 施源器材料,尤其是高密度材料(如304不锈钢)和新型技术材料(如3D打印PLA),对192Ir后装源的吸收剂量影响需引起施源器开发人员和临床应用者的足够重视。 相似文献
994.
Peter Düking Christoph Zinner Jennifer L. Reed Hans-Christer Holmberg Billy Sperlich 《Scandinavian journal of medicine & science in sports》2020,30(12):2291-2304
Monitoring variations in the functioning of the autonomic nervous system may help personalize training of runners and provide more pronounced physiological adaptations and performance improvements. We systematically reviewed the scientific literature comparing physiological adaptations and/or improvements in performance following training based on responses of the autonomic nervous system (ie, changes in heart rate variability) and predefined training. PubMed, SPORTDiscus, and Web of Science were searched systematically in July 2019. Keywords related to endurance, running, autonomic nervous system, and training. Studies were included if they (a) involved interventions consisting predominantly of running training; (b) lasted at least 3 weeks; (c) reported pre- and post-intervention assessment of running performance and/or physiological parameters; (d) included an experimental group performing training adjusted continuously on the basis of alterations in HRV and a control group; and (e) involved healthy runners. Five studies involving six interventions and 166 participants fulfilled our inclusion criteria. Four HRV-based interventions reduced the amount of moderate- and/or high-intensity training significantly. In five interventions, improvements in performance parameters (3000 m, 5000 m, Loadmax, Tlim) were more pronounced following HRV-based training. Peak oxygen uptake () and submaximal running parameters (eg, LT1, LT2) improved following both HRV-based and predefined training, with no clear difference in the extent of improvement in . Submaximal running parameters tended to improve more following HRV-based training. Research findings to date have been limited and inconsistent. Both HRV-based and predefined training improve running performance and certain submaximal physiological adaptations, with effects of the former training tending to be greater. 相似文献
995.
PurposeThe impact of the adherence to dietary guidelines of early-stage breast cancer (EBC) patients on body composition changes during treatment is not entirely defined. This study aimed to evaluate the role of an evidence-based nutrition educational intervention, according to adherence to dietary guidelines, in EBC patients.MethodsThis prospective study included EBC patients, candidates for neoadjuvant/adjuvant therapy. Patients received an evidence-based tailored nutrition educational intervention. The adherence to dietary guidelines, anthropometric and dietary assessments, and blood glucose and lipid profile tests were evaluated at baseline and after a 12-months nutritional intervention.ResultsTwo hundred and forty-three patients were enrolled. At baseline, 38.3% and 23.9% of patients were overweight and obese, weight gain ≥5% (compared to 6-months before enrollment) and central obesity were observed in 47.3% and 52.7% of patients, respectively. Adherence to dietary guidelines was low (median Med-Diet score: 6 [IQR 4–8]). After the nutritional intervention (median follow-up: 22 months [range 12–45]), adherence to dietary guidelines significantly increased (median Med-Diet score: 12 [IQR 8–13]), p < 0.0001). High adherence to dietary guidelines (defines as Med-Diet score ≥10) significantly correlated with: 1) overall weight loss ≥5% (21.8% vs. 2.5%, p = 0.003); 2) median BMI drop (from 25.6 kg/m2 to 24.4 kg/m2, p = 0.003); 3) lower prevalence of central obesity (38.2% vs. 7.2%, p = 0.01); 4) improvement in blood glucose levels and lipid profile.ConclusionThis study suggests that an evidence-based tailored nutrition educational intervention during treatment for EBC significantly increases overall adherence to dietary guidelines, and it improves both anthropometric measures and serum metabolic biomarkers in patients with high adherence. 相似文献
996.
目的:进一步研究各类抗精子抗体对生育的影响。方法:临床应用ELISA法检测血清抗精子抗体。结果:ELISA法操作简单、方便迅速、灵敏性高、特异性强、准确性强、临床效果好。结论:深入研究生殖相关抗原对于了解生殖过程中的信号传导机理和解决不孕不育中的免疫病理具有现实意义。 相似文献
997.
Haozhen Li Quan Zhu Kaixuan Li Ziqiang Wu Zhengyan Tang Zhao Wang 《Translational andrology and urology》2021,10(2):830
BackgroundKetamine abuse has been linked to the system''s damage, presenting with lower urinary tract symptoms (LUTS). While the pathogenesis of ketamine-induced urinary damage is not fully understood, fibrosis is believed to be a potential mechanism. A metabolomic investigation of the urinary metabolites in ketamine abuse was conducted to gain insights into its pathogenesis.MethodsA rat model of ketamine induced bladder fibrosis was established through tail vein injection of ketamine hydrochloride and control group was established through tail vein injection of the equivalent normal saline. Hematoxylin and eosin (H&E) staining and Masson trichrome staining were performed to evaluated bladder pathology. Urinary components were detected based on a metabolomic approach using ultra-high performance liquid tandem chromatography quadrupole time of flight mass spectrometry (UHPLC-QTOFMS platform). Orthogonal projections analyzed the data to latent structures discriminant analysis (OPLS-DA) and bioinformatics analysis.ResultsThe rat model of ketamine induced bladder fibrosis was confirmed through H&E and Masson trichrome staining. There were marked differences in the urinary metabolites between the experimental group and the control group. Compared to the control group, 16 kinds of differential metabolites were up-regulated and 102 differential metabolites were down-regulated in the urine samples of the ketamine group. Bioinformatics analysis revealed the related metabolic pathways.ConclusionsUsing a ketamine-induced bladder fibrosis rat model, this study identified the differential urinary metabolites expressed following ketamine treatment. These results provide vital clues for exploring the pathogenesis of ketamine-induced LUTS and may further contribute to the disease''s diagnosis and treatment. 相似文献
998.
比较心脏死亡器官捐献(donation after cardiac death,DCD)供肾与传统尸体供肾肾移植的临床效果.方法 回顾性分析2012年1月至2013年2月在郑州人民医院实施肾移植的70例患者的临床资料.根据供肾来源分为DCD供肾组(DCD组,22例)和传统尸体供肾组(传统组,48例).患者均签署知情同意书,符合医学伦理学规定.比较两组患者术后7、14、28 d肾功能指标血尿素氮(BUN)和血清肌酐(Scr)水平差异.比较两组患者术后1个月内并发症发生情况及预后情况.结果 DCD组术后7、14 d的BUN和Scr水平均明显高于传统组(均为P<0.01);DCD组术后28 d的Scr水平亦明显高于传统组(P<0.05),两组BUN水平差异无统计学意义(P>0.05).与传统组比较,DCD组的移植物功能延迟恢复(DGF)、急性排斥反应(AR)、感染、移植肾切除的发生率及死亡率明显增高,差异有统计学意义(均为P<0.01).结论 DCD供肾肾移植术后早期肾功能恢复情况不如传统尸体供肾,且围手术期内各种并发症的发生率及死亡率也明显高于传统尸体供肾肾移植. 相似文献
999.
1000.
Gian Piero Guerrini Alessio Vagliasindi Rosalba Lembo Luciano Solaini Paolo Soliani 《Journal of investigative surgery》2017,30(2):110-115
Introduction: The ideal surgical approach for pulmonary metastasectomy remains controversial. Thoracoscopic surgery may offer advantages in quality of life outcomes, with equivalent oncologic long-term results. This study aimed to demonstrate the validity of video-assisted thoracoscopic surgery (VATS) in the treatment of lung metastases. Methods: In all 224 patients who underwent 300 VATS metastasectomies from January 2000 to December 2013 were retrospectively reviewed. Sixty-nine patients underwent major resection (68 thoracoscopic lobectomies and one pneumonectomy) and 155 patients underwent a wedge resection/segmentectomy. Complete curative pulmonary resections were performed in 219 (97%) cases. The Kaplan–Meier method was used to estimate survival curves. Univariate and subsequent multivariate Cox model regression were performed to identify independent factors of overall survival. Results: One hundred eighty-six patients developed lung metastases from epithelial tumors, 28 from sarcomas, seven from melanomas, and three from germ cell tumors. The final pathological examination revealed no cases of R1 disease. After a mean follow-up of 40 months, 118 patients (53%) had died. According to a multivariate analysis, a better prognosis was not observed for patients with a particular histological type; in addition, disease-free interval time, age, number of metastases, and type of surgery did not have any statistical influence on long-term survival. Conclusions: Thoracoscopic surgery is a safe and efficacious procedure, with a five-year overall survival that is equivalent to open surgery. 相似文献