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21.
目的:首次研究文冠果果壳的化学成分。方法:采用柱色谱和光谱方法。结果:从文冠果果壳中分得2种甾醇,经鉴定为:(3β,5α,20R,24S)-豆甾-7,反-22-二烯-3-醇和(3β,5α,20R,24R)-豆甾-7-烯-3-醇。结论:2种甾醇在文冠果中均为首次分得。  相似文献   
22.
Mortality and morbidity of children received veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) support after cardiac surgery remain high despite remarkable advances in medical management and devices. The purpose of this study was to describe outcomes and risk factors of applying VA‐ECMO in the surgical pediatric population. We retrospectively analyzed 85 consecutive pediatric patients (aged <18 years) who received postcardiotomy VA‐ECMO from January 2010 to December 2018. Median (IQR) age at ECMO implantation in this cohort was 12.7 (6.4, 43.2) months, median weight was 8.5 (6.0, 12.8) kg, mean ECMO duration was 143.2 ± 81.6 hours and mean hospital length of stay was 48.4 ± 32.4 days. Seventy‐five patients (88.2%) were indicated for postcardiotomy cardiogenic shock. The successful ECMO weaning rate was 70.6% and in‐hospital mortality was 52.9%. The most common diagnosis was transposition of great arteries (n = 18, 21.2%), while acute kidney injury occurred most often (n = 64, 75.3%). Multivariate logistic regression analysis showed that thrombocytopenia, hemolysis, and nosocomial infection were positively correlated with in‐hospital mortality. Multivariate Cox proportional hazard regression analysis presented that thrombocytopenia significantly increased the 180‐day mortality in patients with successful weaning. Therefore, multiple factors had adverse effects on prognosis. Patient selection and procedures from ECMO implantation to weaning need to be closely monitored and performed in a timely manner to improve outcome.  相似文献   
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24.
Lei  Cao  Chuzhong  Li  Chunhui  Liu  Peng  Zhao  Jiwei  Bai  Xinsheng  Wang  Yazhuo  Zhang  Songbai  Gui 《Neurosurgical review》2021,44(3):1737-1746
Neurosurgical Review - Since there are many approaches for successful craniopharyngioma resection, how to choose a suitable approach remains problematic. The aim of this study was to summarize...  相似文献   
25.
BackgroundPyriform sinus fistula (PSF) is a rare congenital anomaly, and the preferred definitive treatment is yet to be verified. In this study, we investigated the treatment outcomes of PSF specifically comparing endoscopic-assisted surgery and endoscopic radiofrequency ablation (RA).MethodsThe medical records of patients treated for PSF at the Shanghai Children's Hospital between October 2016 and September 2019 were retrospectively evaluated.ResultsThere were 93 girls and 98 boys. The median age at onset and operation was 3 years and 5 years, respectively. Endoscopic-assisted surgery was performed in 143 patients. During the same period, RA was performed in 48 patients, and 10 of them concurrently underwent incision and drainage of neck abscesses. Longer hospital stay was found in the endoscopic-assisted surgery group than in the RA group (10.50 ± 3.93 vs. 5.02 ± 3.30 days, P < 0.001). Postoperative complications were not significantly different between the two groups, except for neck infection (0 vs. 8.3%, P = 0.004). After a median follow-up period of 21 months, no significant difference was found between the two groups in terms of recurrence (1.4% vs. 0, P = 0.560).ConclusionPatients treated with RA had a significantly shorter hospital stay than those treated with endoscopic-assisted surgery. Outcomes of endoscopic-assisted surgery and RA were not significantly different for the management of PSF and treatment method should be tailored to the patient.Level of evidenceIV.  相似文献   
26.
Hepatic ischemia–reperfusion injury (HIRI) is of common occurrence during liver surgery and transplantation. Pinocembrin (PIN) is a kind of flavonoid monomer extracted from the local traditional Chinese medicine Penthorum chinense Pursh (P. chinense). However, the effect of PIN on HIRI has not determined. We investigated the protective effect and potential mechanism of PIN against HIRI. Model mice were subjected to partial liver ischemia for 60 min, experimental mice were pretreated with PIN orally for 7 days, and H2O2-induced oxidative damage model in AML12 hepatic cells was established in vitro. Histopathologic analysis and serum biochemical levels revealed that PIN had hepatoprotective activities against HIRI. The variation of GSH, SOD, MDA, and ROS levels indicated that PIN treatments attenuated oxidative stress in tissue. PIN pretreatment obviously ameliorated apoptosis, and restrained the expression of HMGB1 and TLR4 in vivo. In vitro, compared with H2O2 group, the contents of ROS, mitochondrial membrane potential, apoptotic cells, and Bcl-2 protein were decreased, while the Bax protein expression was increased. Moreover, HMGB-1 small interfering RNA test and western blotting showed that PIN pretreatment reduced HMGB1 and TLR4 protein levels. In conclusion, PIN pretreatment effectively protected hepatocytes from HIRI and inhibited the HMGB1/TLR4 signaling pathway.  相似文献   
27.
PurposeTo investigate the clinical characteristics, chemosensitivity, and outcome of metastatic upper tract urothelial carcinoma (UTUC).Patients and MethodsRecords of patients with metastatic UTUC since January 2005 were retrieved from a database that included clinical and survival data. Statistical analyses including survival and multivariate analyses of factors were respectively performed by the Kaplan-Meier method and Cox proportional hazard model.ResultsA total of 250 consecutive UTUC cases were evaluated. There were 56 patients (22.4%) with initially diagnosed stage IV disease. The most common metastatic sites were lung (39.6%), distant lymph nodes (39.2%), bone (19.6%), liver (18.0%), and adrenal gland (7.2%), respectively, and the local recurrence rate was 10.4%. Two hundred thirteen patients received first-line chemotherapy. The overall response rate was only 28.7% and the median progression-free survival time was only 5.0 months. The overall survival time of the cohort was 18.0 months. Multivariate analyses showed that initially diagnosed stage IV disease, number of metastatic organs ≥3, no response to chemotherapy and cycles of chemotherapy ≤2 were adverse prognosticators for overall survival.ConclusionUTUC presented to be more prone to metastasize than locally recur and thought to have low chemosensitivity. Stage IV disease at initial diagnosis, number of metastatic organs, response and cycles of chemotherapy were independent prognosticators for metastatic UTUC.  相似文献   
28.
微量补体反应性溶血测定法   总被引:3,自引:2,他引:3  
白云  朱锡华 《免疫学杂志》1994,10(2):127-129
本文报道从酵母多糖活化的急性期患者血浆中分离C^-56复合物,并经DEAE-纤维素DE-32阴离子交换层析纯化。利用微孔板和自动微孔板测定仪建立了一种简单,灵敏,准确的微量反应性溶血测定法。  相似文献   
29.
喉癌中p16基因突变和甲基化的研究   总被引:3,自引:0,他引:3  
目的 探讨p16基因在喉癌发生发展中的作用和在喉癌中的失活机制。方法 应用聚合酶链反应-单链构象多态性分析(polymerase chain reaction-single strand conformation polymorphismanaly-sis,PCR-SSCP)银染方法和PCR甲基化敏感内匹酶方法检测32例喉癌和相应癌旁组织的p16基因第1,第2外显子突变和甲基化热点区域部分内切酶  相似文献   
30.
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields.  相似文献   
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