Preparation and morphological investigation on bioactive ion-modified carbonated hydroxyapatite-biopolymer composite ceramics as coatings for orthopaedic implants

2019 ◽

Keyword(s):

Melting Point ◽

Lattice Constant ◽

Single Phase ◽

Solid Phase ◽

Partial Replacement ◽

Metallic Silver ◽

Solid Phase Reaction ◽

Composite Ceramics ◽

Carbonated Hydroxyapatite ◽

X Ray

The study is devoted to the preparation of antimicrobial Ag-containing bioactive calcium phosphate ceramics based on carbonated hydroxyapatite and to the determination of the dependence of its phase composition and microstructure on the synthesis temperature. Composite ceramics was obtained by sintering powders of carbonated hydroxyapatite (CHA), synthesized as a result of a reaction between calcium carbonate and phosphoric acid, with the addition of silver nitrate. Ceramics were sintered at 900 and 1000 °C temperatures, i.e., temperatures below and above the melting point of silver. X-ray analysis, electron microscopy, and infrared spectroscopy showed that synthesis at a 900 °C temperature (below the melting point of metallic silver) produces a two-phase composite based on CHA with inclusions of silver nanoparticles smaller than 50 nm in size. From X-ray analysis, with an increase in silver concentration, the lattice constant a remains practically unchanged, while the constant c ‒ increases. This behavior, due to the significant difference in the ionic radii of calcium and silver (Ca2+ ‒ 0.99 Å, Ag+ ‒ 1.28 Å), usually leads to the preferential substitution of Ca(1) sites in the CHA and a linear increasing in the lattice parameters of the CHA with the Ag concentration. That is, even at relatively low temperatures, as a result of the solid-phase reaction in CHA, partial replacement of calcium ions by silver ions occurs and Ag-substituted ceramics are formed. At temperatures above 1000 °C, a single-phase silver-substituted product is synthesized where part of the Ca2+ ions is replaced by Ag+ ions. At the same time, the lattice constant c continues to increase, and in the electron microscopic images only the apatite grain structure is visible without any inclusions. Sintering of composite ceramics at a temperature when silver is in the liquid phase and more easily dissociates into ions compared to the solid phase, results in a single-phase silver-substituted ceramic.

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Pressureless densification and properties of TiB 2 –B 4 C composite ceramics with Ni as additives

Micro & Nano Letters ◽

10.1049/mnl.2017.0709 ◽

2018 ◽

Vol 13 (7) ◽

pp. 947-950 ◽

Cited By ~ 5

Author(s):

Li Ma ◽

Jincheng Yu ◽

Xue Guo ◽

Yujun Zhang ◽

Hongyu Gong

Keyword(s):

Composite Ceramics

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Wear of orthopaedic implants and artificial joints

10.1533/9780857096128 ◽

2012 ◽

Cited By ~ 4

Author(s):

Saverio Affatato

Keyword(s):

Orthopaedic Implants ◽

Artificial Joints

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Features hormonal hemostasis in patients with benign hyper-plastic processes of breasts

HEALTH OF WOMAN ◽

10.15574/hw.2016.115.72 ◽

2016 ◽

pp. 72-74 ◽

Cited By ~ 2

Author(s):

M. Makarenko ◽

◽

D. Govsieiev ◽

O. Gromova ◽

L. Martynova ◽

...

Keyword(s):

Luteal Phase ◽

Reproductive Organs ◽

Breast Diseases ◽

Hormonal Changes ◽

Morphological Investigation ◽

Fibrocystic Disease ◽

X Ray ◽

Pelvic Organs ◽

Hormone Research ◽

Gynecological Diseases

The objective: to study the incidence of gynecological diseases, clinical and hormonal parameters of the menstrual cycle in patients with benign hyper-plastic processes of breasts. Patients and methods. 65 women with various forms of mastitis were investigated. The following investigations were conducted: mammologistic and gynecological investigation, mommologistic X-ray investigation, ultrasound of breasts and of the pelvic organs, endometrial aspiration biopsy that was followed by cytology; when it was necessary the diagnostic laparoscopy, colposcopy, hysteroscope with curettage and morphological investigation of the endometrium, hormone research and rectal temperature measurements were conducted. Results. The frequency of the benign breast diseases was set: fibrocystic disease of breast – 32 women (49.2±6.20%), fibrous of breast – 16 women (24.6±5.34%), nodular of breasts – 8 women (12.3±4.07%), fibroadenoma – 6 women (9.2±3.59%), nodular disease of breasts on the background of fibroid changes – 3 women (4.6±2.60%). All in all, 96.9±2.14% of the patients had any gynecological diseases. Thus, the average age of the ‘debut’ of mastitis was 31.4±1.09 years; the hyper-plastic processes in the uterus was 35.2±1.17 years. Anovulation was detected in 17 (47.2±8.3%) patients, the lack of the luteal phase (NLF) was detected in 11 (30.6±7.6) patients. Conclusions. Identified hormonal changes are typical for patients with the hyper-plastic processes of the reproductive organs with different localization (breasts, uterus, ovaries). Due to the commonality of the hormone changes in most cases mastitis is combined with the various gynecological diseases (96.9±2.14%). Key words: gynecological pathology, hormonal changes, breast, factors of risk.

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Systematics of Hymenophyllum subgenus Mecodium (Hymenophyllaceae) in Taiwan

Systematic Botany ◽

10.1600/036364419x15710776741413 ◽

2019 ◽

Vol 44 (4) ◽

pp. 753-767

Author(s):

Tian-Chuan Hsu ◽

Yu-Fang Huang ◽

Yi-Shan Chao

Keyword(s):

Phylogenetic Relationships ◽

The Philippines ◽

Common Element ◽

Morphological Investigation ◽

Eastern Asia ◽

Type Specimens ◽

The Status ◽

Molecular Phylogenetic ◽

A New Species ◽

Independent Species

Abstract—Hymenophyllum subg. Mecodium, composed of the taxonomically notorious H. polyanthos and approximately 15 other closely related taxa, is a common element of filmy fern communities in the tropical and subtropical moist forests. In Taiwan, although only H. polyanthos and one or two closely related taxa were recognized in recent studies, considerable morphological variation has been observed among populations throughout the island. Thus, we conducted an extensive morphological investigation, as well as a molecular phylogenetic analysis, to clarify the specific diversity and phylogenetic relationships within Hymenophyllum subg. Mecodium in Taiwan. Field and herbaria surveys helped in recognizing five morphs in Taiwan, mainly differentiated by the combination of certain traits, viz., the presence or absence of stipe wings, general frond size and shape, degree of laminar crispation, sori position, and involucre shape. The different morphs had diverse ecological preferences. The phylogenetic tree, inferred from the sequences of the plastid loci rbcL and rps4-trnS, demonstrated that Hymenophyllum subg. Mecodium materials in Taiwan comprise several well-supported lineages, mostly corresponding to the classification based on morphology. Comparing with the protologues and type specimens of 34 related scientific names, the five morphs are herein recognized as five independent species. A new species, Hymenophyllum exquisitum, is described here. Also, the status of H. paniculiflorum is reconfirmed and that of H. fujisanense, H. parallelocarpum, and H. punctisorum reinstated. Only H. exquisitum and H. parallelocarpum are endemic to Taiwan among all the species studied. In addition, the names Hymenophyllum blumeanum, H. integrum, H. microsorum, H. polyanthos, H. tenellum, and H. wrightii are now excluded from the regional flora, and several related taxa from China, Taiwan, and the Philippines are treated as synonyms. This study unravels the deep phylogenetic relationships within Hymenophyllum subg. Mecodium in Taiwan and Eastern Asia.

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Orthopaedic implants. Forgings

10.3403/00230778 ◽

1990 ◽

Keyword(s):

Orthopaedic Implants

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Implants for surgery. Roentgen stereophotogrammetric analysis for the assessment of migration of orthopaedic implants

10.3403/30217462 ◽

2013 ◽

Keyword(s):

Orthopaedic Implants ◽

Roentgen Stereophotogrammetric Analysis

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EFFECTIVENESS OF PUNCTURE BIOPSIES OF THE PANCREAS UNDER ULTRASOUND GUIDANCE

Problems in oncology ◽

10.37469/0507-3758-2017-63-3-475-478 ◽

2017 ◽

Vol 63 (3) ◽

pp. 475-478

Author(s):

Alla Mikhetko ◽

Dmitriy Zakharov ◽

V. Perov ◽

I. Belova

Keyword(s):

Ultrasound Guidance ◽

Morphological Investigation ◽

Cytological Examination ◽

Comparison Of Results ◽

Histological Data ◽

The Republic ◽

Cytological Method ◽

Cystic Pancreatic Lesions ◽

Histological Form

The results of 205 puncture biopsies of solid and cystic pancreatic lesions performed in 202 patients at the Republican Oncological Dispensary of the Republic of Karelia for a 7-year period (2009-2015) are presented. Informative material for morphological investigation was obtained in 95.5% of cases. A comparison of results of cytological examination of the material from 56 patients with pancreatic lesions with histological data was carried out. The efficiency of the cytological method was 90.6%, sensitivity - 87.8%, specificity - 100%. To determine histological form of tumor in cytological examination of the material of the pancreas was successful in 82.1% of cases.

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