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61.
IntroductionTargeted Radionuclide Therapy (TRT) is a branch of cancer medicine dealing with the therapeutic use of radioisotopes associated with biological vectors accumulating in the tumors/targets, indicated as Molecular Radiotherapy (MRT), or directly injected into the arteries that supply blood to liver tumour vasculature, indicated as Selective RT (SRT). The aim of this work is to offer a panoramic view on the increasing number of commercially-available TRT treatment planning systems (TPSs).Materials and methodsA questionnaire was sent to manufacturers' representatives. Academic software were not considered. Questions were grouped as follows: general information, clinical workflow, calibration procedure, image processing/reconstruction, image registration and segmentation tools, time-activity curve (TAC) fitting and absorbed dose calculation.ResultsAll software reported have CE-marking. TPSs were divided between SRT-dedicated software [4] and MRT [5] dosimetry software. In SRT, since no kinetic process is involved, absorbed dose calculation does not require TAC fitting, and image registration is not fully developed in all TPS. All software requires a radionuclide-specific calibration. In SRT, a relative image calibration can be obtained by scaling the counts to a known activity. Automated VOI contouring and rigid/deformable propagation between different acquisitions time-points is implemented in most TPSs, although DICOM export is rare. Different TAC fits are available depending on the number of time-points. Voxel S-value and Local deposition methods are the most frequent dosimetric approaches; dose-voxel kernel convolution and semi-Monte Carlo method are also available.ConclusionsAvailable TPSs allows performing personalized dosimetry in clinical practice. Individual variations in methodology/algorithms must be considered in the standardisation/harmonization processes.  相似文献   
62.
A variant hemoglobin due to structural change in the β chain was found in the central part of Bali island, Indonesia, during field studies on the genetic variation of the Indonesian crabeating monkey (Macaca fascicularis), and was named Hb Bali (Macaca). Structural analysis yielded the following results. (1) The amino acid sequence of the normal β chain of the crab-eating monkey coincided with that of the Japanese monkey (M. fuscata) and the pig-tailed monkey (M. nemestrina). (2) Asn at the 80th position from the amino terminal of the β chain was substituted by Lys in Hb Bali. This substitution appeared to have little harmful effect on the carrier, since the hematological characteristics of the heterozygous carriers were not different from those of normal individuals.  相似文献   
63.
 1988年我室又发现一种新的慢泳异常胎儿血红蛋白(HbF)。先证者为一健康汉族女婴。醋纤膜电泳(pH8.6)示变异体区带位于HbF与Hb A_2之间,反相高效液相色谱(HPLC)示正常GγI峰前方出现一异常峰。异常Hb含量为Hb总量的16.8%。理化性质测定该变异体为一轻度不稳定Hb。结构分析证明该变异体为GγI链第119位(GH2)的甘氨酸(Gly)被精氨酸(Arg)取代。γ链GH2位于α_1γ_1接触面,此处的氨基酸置换可导致Hb的不稳定。此变异体被命名为HbF-新晋[~(GγI)119(GH2)Gly→Arg]。  相似文献   
64.
目的:探讨3D打印技术辅助前侧微创入路手术治疗不稳定型骨盆骨折的临床疗效及安全性。方法:选择2014年8月到2017年2月在我院诊治的骨盆骨折患者78例作为研究对象,按照随机信封抽签原则分为观察组与对照组,每组各39例。对照组采用常规X线与CT进行手术设计,观察组采用3D打印技术进行手术设计,两组都给予前侧微创入路手术治疗,比较两组的手术时间、切口长度、骨折愈合时间、术中出血量、术中和术后并发症的发生情况及术后3个月的骨盆功能优良率。结果:所有患者都完成手术,无术中严重并发症发生,两组手术时间及切口长度对比差异无统计学意义(P0.05)。对照组的骨折愈合时间、术中出血量显著高于观察组(P0.05)。观察组术后并发症的发生率(5.1%)显著低于对照组(25.6%)(P0.05),术后3个月的骨盆功能优良率(97.4%)显著高于对照组(74.4%)(P0.05)。结论:与常规X线与CT前侧微创入路手术治疗比较,3D打印技术辅助前侧微创入路手术治疗不稳定型骨盆骨折可为患者提供安全、有效、个性化的治疗,减少术后并发症的发生,改善患者的骨盆功能。  相似文献   
65.

Background

The nuclear genome of Chlamydomonas reinhardtii encodes a dozen hemoglobins of the truncated lineage. Four of these, named THB1–4, contain a single ~130-residue globin unit. THB1, which is cytoplasmic and capable of nitric oxide dioxygenation activity, uses a histidine and a lysine as axial ligands to the heme iron. In the present report, we compared THB2, THB3, and THB4 to THB1 to gain structural and functional insights into algal globins.

Methods

We inspected properties of the globin domains prepared by recombinant means through site-directed mutagenesis, electronic absorption, CD, and NMR spectroscopies, and X-ray crystallography.

Results

Recombinant THB3, which lacks the proximal histidine but has a distal histidine, binds heme weakly. NMR data demonstrate that the recombinant domains of THB2 and THB4 coordinate the ferrous heme iron with the proximal histidine and a lysine from the distal helix. An X-ray structure of ferric THB4 confirms lysine coordination. THB1, THB2, and THB4 have reduction potentials between ?65 and ?100 mV, are capable of nitric oxide dioxygenation, are reduced at different rates by the diaphorase domain of C. reinhardtii nitrate reductase, and show different response to peroxide treatment.

Conclusions

Three single-domain C. reinhardtii hemoglobins use lysine as a distal heme ligand in both Fe(III) and Fe(II) oxidation states. This common feature is likely related to enzymatic activity in the management of reactive oxygen species.

General significance

Primary structure analysis of hemoglobins has limited power in the prediction of heme ligation. Experimental determination reveals variations in this essential property across the superfamily.  相似文献   
66.
目的:分析对比股骨近端防旋髓内钉(PFNA)与股骨近端锁定钢板(PFLP)治疗老年股骨转子间不稳定骨折的临床疗效。方法:回顾性分析我院骨外科2009年4月至2013年4月收治的老年股骨转子间不稳定骨折患者90例,根据患者手术方式的不同,将其分为PFNA组及PFLP组,各45例。对比分析两组患者术中出血量、手术持续时间及骨折愈合时间术后髋关节功能及内固定并发症情况。结果:PFNA组髋关节功能Harris评分优良率91.11%明显高于PFLP组的71.11%(P0.05);PFNA组比PFLP组骨折愈合时间短、内固定并发症少,比较差异有统计学意义(P0.05)。结论:应用PFNA治疗老年股骨转子间不稳定骨折患者具有骨折愈合时间短、髋关节功能恢复好、术后内固定并发症少的特点,治疗效果较PFLP更满意。  相似文献   
67.
A new hemoglobin variant found in a mother and her child was characterized by column chromatography of the tryptic hydrolysate of the aminoethylated, glycinamidated -chain, followed by chymotryptic digestion of the abnormal T-9 peptide and amino acid analyses. It was shown to be 2 2 73(E17) Asp Val and named Hb Mobile.This work was supported in part by Research Grants AM0780 and AM13173 from the National Institute for Arthritis and Metabolic Disease.  相似文献   
68.
Oxygenation of heme-mercaptide as well as spectroscopic characteristics of the dioxygen complex formed have been studied. Absorption and magnetic circular dichroism spectra of the O2 complex support the retention of mercaptide in the heme fifth position. A release of O2? in the decomposition of the oxygenated complex and an independent formation of the latter from hemine-dimercaptide and O2? together with electron paramagnetic resonance and Mössbauer data support the O2 presence in the heme coordination sphere. The similarity of optical and magnetic circular dichroism spectra and the closeness of the KCOKO2 ratio for oxy-heme-mercaptide and oxycytochrome P450 unequivocally confirm the presence of an axial cystein mercaptide ligand in oxycytochrome P450.  相似文献   
69.
The production of five chain variants (Hb G-Georgia, Hb St. Luke's, Hb Lloyd, Hb Montgomery, and Hb G-Philadelphia) in heterozygotes was evaluated through hematological observations, hemoglobin quantification, and biosynthetic studies. All heterozygotes for Hb St. Luke's and Hb Lloyd and most heterozygotes with Hb G-Georgia and Hb Montgomery had normal hematology and average / values of about 1.1. They were assigned a normal genotype (G/), although the proportions of Hb St. Luke's and Hb G-Georgia were low (10 to 13%) and those of Hb Lloyd and Hb Montgomery twice as high (20%). Data from short-term incubations confirmed this genotype for some of these heterozygotes. Isolated Hb St. Luke's and Hb G-Georgia gave low G/ values (0.2 and 0.3) indicating that these Hb variants were defective at the level of Hb assembly. Isolated Hb Montgomery and Hb G-Philadelphia, however, gave higher G/ values of 0.6 and 0.8, respectively. A second type of variability existed among Hb G-Georgia (20 vs. 13%), Hb Montgomery (28 vs. 20%), and Hb G-Philadelphia (47 vs. 34%) heterozygotes, in whom the levels of Hb G differed. The occurrence of higher levels of these three chain heterozygosities was associated with hematological or biosynthetic evidence of a mild or moderate chain deficiency due to an -thalassemia-2 heterozygosity (G/0 or 0G/) or a homozygosity (0G/0), respectively.This study was supported in part by USPHS Research Grants HLB-05168 and HLB-15158.  相似文献   
70.
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