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11.
A new enzyme-linked immunosorbent assay (ELISA) method for quantitative determination of monoester-type aconitic alkaloids was developed. The antibodies derived from the immunogen of benzoylmesaconine (BM) could be electively affined to benzoylaconitine-type alkaloids with an ester bond (14-benzoyl-), especially to benzoylhypaconine (BH, 140.02% of cross-reactivity). The effective working range of BH was 1 ng/ml to 5 μg/ml; the lower limit of detection and the quantification were 0.35 and 0.97 ng/ml, respectively. The values of CV for intra-day and inter-day assays and recovery ratios were in acceptable ranges. The results of stability experiments were also satisfactory. This validated method was employed for pharmacokinetic study of BH in rats and the bioavailability orally administered was estimated to be 16.3%.  相似文献   
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Cancer metastasis is one of the biggest challenges in cancer treatments since it increases the likelihood that a patient will die from the disease. Therefore, the availability of techniques for the early detection and quantification of tumors is very important. We have prepared cyanine 7.5 NHS ester (Cy7.5) and folic acid (FA) conjugated biodegradable mesoporous silica nanoparticles (bMSN@Cy7.5-FA NPs) (~100 nm) for visualizing tumors in vivo. The fluorescence spectra revealed that the emission peak of bMSN@Cy7.5-FA NPs had a red-shift of 1 nm. Confocal immunofluorescent images showed that bMSN@Cy7.5-FA NPs had an excellent targeting ability for visualizing cancer cells. In vivo fluorescence imaging has been conducted using an orthotopic model for pancreatic cancer within 48 h, and the fluorescence intensity reached a maximum at a post injection time-point of 12 h, which demonstrated that the use of bMSN@Cy7.5-FA NPs provides an excellent imaging platform for tumor precision therapy in mice.  相似文献   
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Cobalamin (cbl) C disease is a rare autosomal recessive inheritance disease, which is the most common cobalamin metabolic disorder. Its clinical phenotype involves multiple systems with varying degrees of severity, where in mild cases can be asymptomatic for many years, whereas severe cases may cause death during the neonatal period. The disease is caused by mutations in the MMACHC gene located on chromosome 1p34.1 that contains 5 exons; among which, exons 1–4 have an 849 bp coding sequence that encodes a protein containing 282 amino acids. Through clinical physical examination and laboratory tests, especially blood and urine screening, we found 28 cblC pediatric patients with clinical manifestations, such as mental retardation, motor development delay, epilepsy, metabolic acidosis, vomiting and diarrhea. By Sanger sequencing, we found homozygous or compound heterozygous mutations of MMACHC in 27 of the patients, and single heterozygous mutation of MMACHC in one of them. The c.609G > A, c.658-660delAAG, c.80A > G and c.482G > A mutations accounted for 43.64% (24/55), 10.91% (6/55), 9.09% (5/55) and 7.27% (4/55) of all the mutations, respectively. This spectrum finding is basically consistent with the previously reported data in Chinese patients. The most common c.609G > A mutation may likely lead to early-onset cblC disease. In previous literature involving a large sample of Caucasian cblC cases, the mutation spectrum of MMACHC gene is almost completely different from that of the Chinese population. The most common mutations in the Caucasian population were c.271dupA, c.394C > T and c.331C > T, which account for 48.05% (542/1128), 13.65% (154/1128) and 7.36% (83/1128) of all the mutant alleles, respectively. The c.271dupA mutation and c.331C > T mutation were mainly associated with early-onset cblC in children less than 1 year old, whilst the c.394C > T mutation was mainly associated with late-onset cblC patients characterised by isolated acute nervous system abnormalities. We also analysed the cause behind the different mutation spectrum of MMACHC gene between the Chinese and Caucasian populations.  相似文献   
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T cell replete HLA-mismatched haploidentical transplantation (HIDT) with post-transplant cyclophosphamide is increasingly becoming an acceptable treatment approach for patients lacking timely access to a suitably matched related donor transplant (MRDT) or matched unrelated donor transplant (MUDT). Multiple recent registry and single-center studies have shown comparable overall survival (OS) and disease-free survival (DFS) rates among HIDT, MRDT, and MUDT with a significantly lower risk of acute and chronic graft-versus-host disease (GVHD) among HIDT recipients. Candidates for allogeneic hematopoietic stem cell transplantation (HSCT) often have access to multiple donor sources, and a relevant question is whether outcomes can be improved with a younger HLA-mismatched haploidentical donor (≤35 years) rather than an older matched related donor (≥35 years) or matched unrelated donor (≥35 years). We analyzed 406 consecutive allogenic HSCT recipients, with a median age of 54 years (range, 19 to 77), after a MRDT with a donor age of ≥35 years (n = 222), MUDT with a donor age of ≥35 years (n = 91), and HIDT with a donor age of ≤35 years (n = 93). Median follow-up time for survivors was 51.5 months. Compared with MRDT and MUDT, HIDT recipients had a similar median age at time of HSCT, hematopoietic cell transplant comorbidity index, disease risk index distribution, and donor recipient sex matching. The survival estimates and relapse incidence at 3 years post-HSCT were OS (64% for MRDT, 54% for MUDT, and 62% for HIDT), DFS (55% for MRDT, 44% for MUDT, and 58% for HIDT), Transplant related mortality (TRM) (19% for MRDT, 16% for MUDT, and 18% for HIDT), and relapse (26% for MRDT, 37% for MUDT, and 24% for HIDT). HIDT recipients had better 3-year relapse rates compared with MUDT recipients (24% versus 37%, P= .048), with similar DFS and OS in a univariate analysis. MRDT recipients had a better relapse rate (26% versus 37%, P = .042) compared with MUDT recipients. Recipients of HIDT also had significantly lower rates of moderate to severe chronic GVHD compared with MRDT and MUDT recipients (P = .01). Multivariable analysis showed no effect of donor on OS, DFS, relapse, and TRM. Recipients of HIDT from a young donor ≤35 years had similar OS, lower rates of chronic GVHD, and better chronic GVHD-free, relapse-free survival compared with patients undergoing transplantation with an MRD or a MUD donor ≥35 years. This study suggests that given a situation where a choice between a young haploidentical relative and an older matched unrelated donor is to be made, one can achieve similar survival with a haploidentical donor and significantly lower rates of chronic GVHD.  相似文献   
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Although myeloablative conditioning (MAC) before haploidentical donor transplant (HIDT) with post-transplant cyclophosphamide is being increasingly used, the optimal preparative regimen remains unclear. In our initial trial, the feasibility of HIDT following a MAC preparative regimen using fludarabine and 12 Gy of total-body irradiation was demonstrated in 30 patients. We now present long-term outcome results, including an additional 52 patients, now with 47 months (16 to 96) median follow-up. Median patient age was 42 (19 to 61) years. The most common diagnoses were acute myelogenous leukemia (51%) and acute lymphoblastic leukemia (33%), and 39% had a high/very high disease risk index (DRI). Engraftment was universal with no cases of primary or secondary graft failure. Grade 3 to 4 acute graft-versus-host disease (GVHD) and moderate to severe chronic GVHD occurred in 17% and 23%, respectively. Nonrelapse mortality (NRM) was 7% at 1 year and 13% at 4 years. Estimated 4-year overall survival (OS), disease-free survival, and cumulative incidence of relapse (CIR) were 67%, 60%, and 27%, respectively. CIR was significantly higher in patients with high/very high- versus low/intermediate-risk DRI (38% versus 20%, P= .032), which led to inferior 4-year OS (50% versus 77%, P = .001). Median time to systemic immunosuppressive therapy (IST) discontinuation was 7.8 months, with 84% of patients off IST at 2 years post-transplant. Current GHVD-free, relapse-free survival (CGRFS) at 2, 3, and 4 years was 60%, 57%, and 60%, respectively. This approach to MAC HIDT results in universal engraftment; low rates of NRM, infection, and clinically significant GVHD; and relatively rapid IST discontinuation, resulting in high rates of CGRFS and survival.  相似文献   
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目的探讨浅表食管癌侵袭深度及分化程度与区域淋巴结转移的关系。方法本院2002年6月至2004年6月总共手术治疗食管癌923例,其中早期浅表食管癌68例,本文就对其术后侵袭深度及分化程度与区域淋巴结转移情况进行回顾性分析。结果本组无手术死亡,全组淋巴结转移率27%,其中高出黏膜型食管癌的淋巴结转移率为38%,侵袭越深,淋巴结转移率越高;分化程度越低淋巴结转移率越高。结论高度重视浅表型食管癌的根治性,对早期食管癌也应按肿瘤外科的原则行食管的次全切除术并常规清扫区域淋巴结。  相似文献   
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Su  Shijie  Hou  Zhaofeng  Wang  Lele  Liu  Dandan  Hu  Junjie  Xu  Jinjun  Tao  Jianping 《Parasitology research》2019,118(4):1159-1169
Parasitology Research - In our previous study, we obtained a large number of differentially expressed genes (DEGs) between second-generation merozoites (MZ-2) and third-generation merozoites (MZ-3)...  相似文献   
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