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991.
Myeloid/Natural Killer Cell Precursor Acute Leukemia Accompanied by Homozygous Protein C Deficiency 总被引:1,自引:0,他引:1
Shimamoto T Nakajima A Katagiri T Ito Y Ohyashiki K 《International journal of hematology》2003,78(2):149-153
A patient with myeloid/natural killer (NK) cell precursor acute leukemia who was also homozygous for protein C deficiency was treated and showed a complete remission while he simultaneously received low molecular weight heparin. He presented with fever spikes, lymphadenopathy, and a bulky tumor of the anterior mediastinum. A bone marrow aspirate showed the infiltration of immature lymphoblastoid cells. The patient's diagnosis was determined to be myeloid/NK cell precursor acute leukemia by morphologic and immunophenotypic analysis (CD7(+)CD33(+)CD34(+)CD56(+)). The patient developed a thrombosis in his jugular vein on cannulation of the internal jugular vein. An examination of the serum levels and the activities of proteins C and S demonstrated a slight decrease in the protein C level but an undetectable protein C activity. The patient received the diagnosis of homozygous protein C deficiency, because both parents were found to have heterozygous protein C activity. Treatment of the patient's leukemia included induction chemotherapy (Ara-C and idarubicin) with concomitant administration of low molecular weight heparin for his homozygous protein C deficiency. He achieved a complete remission without expressing any thrombosis during the course of chemotherapy. To our knowledge, this is the first case ever described in which acute myeloid leukemia was complicated with homozygous protein C deficiency. 相似文献
992.
Joachim G. Eichhorn MD Frederick R. Long MD Claudia Jourdan MD Johannes T. Heverhagen MD PhD Sharon L. Hill ARNP Subha V. Raman MD John P. Cheatham MD 《Catheterization and cardiovascular interventions》2008,72(4):544-551
Objective : To evaluate varying CT settings to visualize pediatric vascular stents in comparison to digital angiography (DA). Background : There is a great clinical interest in substituting noninvasive methods to follow up children with congenital heart disease after interventional treatment. Materials and Methods : CT studies in small children with transcatheter placed stents were reviewed, retrospectively. Furthermore, eight stents were implanted in tubes and partially obstructed. CT exams were performed on varying scanners (4 up to 64 slices) with corresponding tube settings. The effects of dose on image quality were evaluated regarding stent size, strut thickness, and in‐stent stenoses in comparison to DA. Results : Fourteen children with 28 implanted stents were identified. Significant differences between higher and lower radiation settings were not found, corresponding with the phantom, where moderate tube setting showed the best results. In vitro, there was an improvement with increasing number of detector rows, which resulted in a decrease of stent strut overestimation (295% down to 201%; P < 0.0001) and a better agreement with DA measurements for mild (78% up to 91%; P = 0.003) and moderate in‐stent stenoses (80% up to 99%; P = 0.0001). Conclusion : Higher radiation exposure settings did not improve image quality, suggesting that the exams could be performed at a lower radiation dose. © 2008 Wiley‐Liss, Inc. 相似文献
993.
994.
Antidepressant and antipsychotic drugs are regularly encountered in different aspects of forensic toxicology, and some cases require the examination of hair samples. In this study, common antidepressant and antipsychotic drugs regarding hair concentrations over the past decades were reviewed. Although numerous publications around method validations, case reports, or controlled dose studies were found, apparently there is a lack of comprehensive data for many substances. Information on the hair length and dosage across the publications varied largely, and case numbers were generally low except for several retrospective controlled dose studies. Many substances were described only in method validations or case reports, and data were obtained from small case numbers. On the contrary, clozapine, haloperidol, amitriptyline, nortriptyline, risperidone and its metabolite, methylphenidate, citalopram, chlorpromazine, chlorprothixene, and quetiapine had a well‐founded database as these substances were investigated in controlled dose studies with higher case numbers. Given the advancements made in analytical techniques over the past years, gas chromatography–mass spectrometry and liquid chromatography with tandem mass spectrometry techniques were the methods of choice and allowed the detection of chemical compounds at low concentrations. The controversy around a potential use of hair analysis to estimate the dosage remains as dose‐concentration studies provided divergent results. A harmonization on the investigated hair length as well as on the extraction protocol would be of favor to achieve better comparability. Although hair analysis research focused mainly on drug abuse, availability of more data on antidepressants and antipsychotics would help to gain better knowledge and assist other forensic investigators. 相似文献
995.
目的:探讨莲必治注射液在儿童患者中的应用合理性以及中药注射剂在儿童患者中的药物利用研究。方法:对2018年某儿童医院应用莲必治注射液的住院患儿资料进行回顾性分析,结合药品说明书以及患儿年龄、体质量,对给药剂量、给药浓度、用药频次及溶剂选择等方面进行统计分析;计算儿童药物利用指数,初步探讨中药注射剂在儿童患者中的合理评价方法。结果:最终纳入1549例患儿,合理性评分均值为5.43分;适应证合理率最低,仅为45.32%(702/1549);给药浓度均值超过规定范围(0.8~1.5 g/L),最小浓度为0.2 g/L,最大浓度达6.25 g/L。年龄方面,≤1岁患儿的儿童药物利用指数-剂量(cdDUI)>1.1,而>4岁患儿的cdDUI<0.9,不同年龄段患儿的儿童药物利用指数-浓度(ccDUI)均>1,尤以≤6个月为著。体质量方面,≤30 kg患儿的儿童药物利用指数(cDUI)均>1.1,而>30 kg患儿的cDUI均<0.9。结论:从年龄、体质量和平均给药剂量、药物利用指数可见,均存在低年龄或低体重患儿莲必治注射液用药量大,而高年龄或高体质量患儿用药量不足的现象,且均存在给药浓度过高的现象。因此,应加强中药注射剂在儿童中应用的合理性评价。 相似文献
996.
Anita R. Peoples Wilfred R. Pigeon Dongmei Li Sheila N. Garland Michael L. Perlis Julia E. Inglis Vincent Vinciguerra Thomas Anderson Lisa S. Evans James L. Wade Deborah J. Ossip Gary R. Morrow Julie Ryan Wolf 《Journal of pain and symptom management》2021,61(2):254-261
ContextPain can be a debilitating side effect of radiation therapy (RT). Data from the general population have shown that sleep disturbance can influence pain incidence and severity; however, less is known about this relationship in patients with breast cancer receiving RT.ObjectivesThis secondary analysis examined the association of pretreatment moderate/severe levels of sleep disturbance with subsequent RT-induced pain after adjusting for pre-RT pain.MethodsWe report on 573 female patients with breast cancer undergoing RT from a previously completed Phase II clinical trial for radiation dermatitis. Sleep disturbance, total pain, and pain subdomains—sensory pain, affective pain, and perceived pain intensity were assessed at pre-RT and post-RT. At pre-RT, patients were dichotomized into two groups: those with moderate/severe sleep disturbance (N = 85) vs. those with no/mild sleep disturbance (control; N = 488).ResultsAt pre-RT, women with moderate/severe sleep disturbance were younger, less likely to be married, more likely to have had mastectomy and chemotherapy, and more likely to have depression/anxiety disorder and fatigue than the control group (all Ps < 0.05). Generalized estimating equations model, after controlling for pre-RT pain and other covariates (e.g., trial treatment condition and covariates that were significantly correlated with post-RT pain), showed that women with moderate/severe sleep disturbance at pre-RT vs. control group had significantly higher mean post-RT total pain as well as sensory, affective, and perceived pain (effect size = 0.62, 0.60, 0.69, and 0.52, respectively; all Ps < 0.05).ConclusionThese findings suggest that moderate/severe disturbed sleep before RT is associated with increased pain from pre-to-post-RT in patients with breast cancer. 相似文献
997.
《Immunopharmacology and immunotoxicology》2013,35(4):673-678
Objective: To probe into application of low dose of FK506(Tacrolimus) in pancreas transplantation.Methods: Effects of low-dose FK506 (Tacrolimus) in pancreas transplantation with examination of ELISA Electron microscopy and TUNEL by method of random control were studied.Results: Blood glucose concentration in control group is higher than that in treated group A (FK506) and treated group B (CsA) 7 days after transplantation (p?<?0.05). Serum C-peptide and insulin concentrations in control group are less than that in treated group A (FK506) and treated group B (CsA) 7 days after transplantation (p?<?0.05). Blood glucose, serum C-peptide and insulin concentrations are same as that in control group, group A (FK506) and group B (CsA) (p?>?0.05).There are more apoptotic nuclei in control group than that in treated group A (FK506) and treated group B (CsA) (p?<?0.05). There is no significant difference between group A (FK506) and treated group B (CsA) in sum of apoptotic nuclei (p?>?0.05). There is no significant difference among treated group A (FK506) and treated group B (CsA) in electron microscopy fields.Conclusion: Low-dose FK506 applied in pancreas transplantation could not only be effective for immunosuppressive, but also be safe for islet cells of pancreas. 相似文献
998.
Durgeshwer Singh Antaryami Singh 《Journal of biomaterials science. Polymer edition》2013,24(17):1269-1285
Hydrogels were prepared using polyvinyl pyrrolidone (PVP) blended with carrageenan by gamma irradiation at different doses of 25 and 40 kGy. Gel fraction of hydrogels prepared using 10 and 15% PVP in combination with 0.25 and 0.5% carrageenan was evaluated. Based on gel fraction, 15% PVP in combination with 0.25% carrageenan and radiation dose of 25 kGy was selected for the preparation of hydrogels with nanosilver. Radiolytic synthesis of silver nanoparticles within the PVP hydrogel was carried out. The hydrogels with silver nanoparticles were assessed for antimicrobial effectiveness and physical properties of relevance to clinical performance. Fluid handling capacity (FHC) for PVP/carrageenan was 2.35 ± 0.39–6.63 ± 0.63 g/10 cm2 in 2–24 h. No counts for Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and Candida albicans were observed in the presence of hydrogels containing 100 ppm nanosilver after 3–6 h. The release of silver from hydrogels containing 100 ppm nanosilver was 20.42 ± 1.98 ppm/100 cm2 in 24 h. Hydrogels containing 100 ppm nanosilver with efficient FHC demonstrated potential microbicidal activity (≥3 log10 decrease in CFU/ml) against wound pathogens, P. aeruginosa, S. aureus, E. coli, and C. albicans. PVP/carrageenan hydrogels containing silver nanoparticles can be used as wound dressings to control infection and facilitate the healing process for burns and other skin injuries. 相似文献
999.
B. Michael Moores 《Radiography》2021,27(2):704-708
ObjectivesThe objectives of the review were to investigate the legal and sociological basis of justification in society in order to fully assess its relevance to radiation protection. The difference between the justification of practices as distinct from the justification of reasons for the justification of individual activities within a practice and the relevance of cost–benefit analysis to this process are key elements.Key findingsJustification of practices as a principle of radiation protection is automatically enshrined within the appropriate legislation once it has been enacted. However, the justification of reasons for justification of activities within a practice are subject to many sociological factors, which are often conflicting and indeterminate and can be subject to political, economic and environmental factors that may change over time. This applies especially to new developments where the primary reason for justification is based upon potential but possibly ill-defined future benefits.ConclusionThe primary mechanism whereby society develops a collective consensus on the justification of practices lies within a legal framework. This represents the mechanism by which society defines the accepted standards that must be applied for acceptance of a practice. The justification of reasons for justifying activities that form part of a practice has largely been ignored within the framework of radiation protection.Implications for practiceThe employment of justification of practices as a fundamental principle of radiation protection should be eliminated since it is already enshrined within the legal framework applicable to applications of ionising radiation. Justification of reasons for pursuing new or modified practices is based upon their perceived benefits to society, which underpins most developments in society. 相似文献
1000.
IntroductionIntracranial aneurysm coil embolisation is a fluoroscopically guided procedure associated with high radiation dose. The increase in the number of coil embolisation procedures raises concern for the amount of radiation and the associated radiation risks to the patients. This research study was conducted to determine the average radiation dose to patients’ thyroid glands and local skin during intracranial aneurysm coil embolisation and to establish preliminary local diagnostic reference levels for this procedure. In this paper, local skin dose refers to the absorbed radiation dose on the areas of the skin exposed to radiation during intracranial aneurysm coil embolisation, namely neck, face and scalp.MethodsThis study employed air-kerma area product meters to determine the local skin dose and diagnostic reference levels during intracranial aneurysm coil embolisation. In addition, thyroid radiation doses were measured using thermo-luminescent dosimeters on a phantom during simulation of embolisation procedures.ResultsThe local skin doses as determined by air-kerma area product ranged between 33 and 125 Gy.cm2. The mean thyroid dose was 9.87 mGy. The established local diagnostic reference level was 52.1 Gy cm2, 17.8 min’ fluoroscopy time and 503 image frames.ConclusionThe average air-kerma area product values and the proposed diagnostic reference levels were lower than most published values for intracranial aneurysm coil embolisation.Implications for practiceThe established local diagnostic reference levels are recommended for use as radiation dose optimisation tool at the research site. The findings of this study cannot be generalised or applied to other hospitals. The complexity of the embolisation procedures was not classified for this study. Further research on diagnostic reference levels for intracranial aneurysm coil embolisation, taking into account the complexity of the procedures, is recommended. 相似文献