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1.
I. C. B. Lima L. F. Oliveira R. T. Lopes 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(3):639-642
Summary One of the great 3D micro tomography (3D-mCT) applications in the medical area is the characterization of bone architecture,
especially when it is spoken in osteoporosis because, among other factors, is characterized by the deterioration of the architecture.
This work shows the 3D quantification, based on stereological concepts, of the bone tissue through 3D-mCT in real time. The
analyses were carried out in femur rat and the 3D visualizations helped to understand bones morphology. The results showed
the potential of this computational technique to verify the capability of characterization of the internal bone structures
and the importance of the threshold level in the binarization process. 相似文献
2.
Zhang Yuanxun Li Deyi Ma Jixiao Huang Qiren 《Journal of Radioanalytical and Nuclear Chemistry》1997,222(1-2):263-265
Bone mineral density (BMD) determination has been performed in 210 selected Shanghai residents of both sexes of age range 15–50 using Hologic QDR-2000 dual energy X-ray absorptiometry (DEXA). The results showed that in female groups the peak value of L1-L4 BMD was 1.023 g/cm2 at the age of 31–35, but in the male groups it was 0.971 g/cm2 aged 26–30 and the peak period lasted till the group aged 46–50. The similar conclusion has also obtained by further statistics. 相似文献
3.
Mi Yeong Kim Kyunghee Lee Hong-In Shin Kyung-Jae Lee Daewon Jeong 《Experimental & molecular medicine》2021,53(1):103
Metabolic activities are closely correlated with bone remodeling and long-term anti-resorptive bisphosphonate treatment frequently causes atypical femoral fractures through unclear mechanisms. To explore whether metabolic alterations affect bone remodeling in femurs and lumbar vertebrae and whether anti-osteoporotic bisphosphonates perturb their reconstruction, we studied three mouse strains with different fat and lean body masses (BALB/c, C57BL6, and C3H mice). These mice displayed variable physical activity, food and drink intake, energy expenditure, and respiratory quotients. Following intraperitoneal calcein injection, double calcein labeling of the femoral diaphysis, as well as serum levels of the bone-formation marker procollagen type-I N-terminal propeptide and the bone-resorption marker C-terminal telopeptide of type-I collagen, revealed increased bone turnover in mice in the following order: C3H > BALB/c ≥ C57BL6 mice. In addition, bone reconstitution in femurs was distinct from that in lumbar vertebrae in both healthy control and estrogen-deficient osteoporotic mice with metabolic perturbation, particularly in terms of femoral trabecular and cortical bone remodeling in CH3 mice. Interestingly, subcutaneous administration of bisphosphonate risedronate to C3H mice with normal femoral bone density led to enlarged femoral cortical bones with a low bone mineral density, resulting in bone fragility; however, this phenomenon was not observed in mice with ovariectomy-induced femoral cortical bone loss. Together, these results suggest that diverse metabolic activities support various forms of bone remodeling and that femur remodeling differs from lumbar vertebra remodeling. Moreover, our findings imply that the adverse effect of bisphosphonate agents on femoral cortical bone remodeling should be considered when prescribing them to osteoporotic patients.Subject terms: Bone, Bone quality and biomechanics 相似文献
4.
Kumosani TA 《Experimental & molecular medicine》2001,33(1):20-22
Ergothioneine is widely distributed in biological systems, particularly in red blood cells of animals. However, it's functional role in human body is not well understood. In order to investigate the biochemical effect of L-ergothioneine, its concentration changes in human blood with respect to ages in healthy individuals was first investigated. L-ergothioneine concentrations in the blood of Saudi males from western province at different stages of life were measured by the procedure of Carlsson et al., 1974. At early stages of life (1-10 years), the concentrations of LER is 1.5-2.0 mg/100 ml. It increases gradually at the age of 11-18 years where it reaches the maximum value of 3.7 mg/100 ml. Then, it declines gradually to 3.0-2.3 mg/ 100 ml during the period of 19-50 years. An increase in the level of LER (2.8 mg/100 ml) was seen at the age of 51+. 相似文献
5.
Kim HY Hwang JY Han BG Lee JY Park EK Kim BJ Lee SH Kim GS Kim SY Koh JM 《Experimental & molecular medicine》2012,44(6):394-402
Adiponectin may affect bone through interactions with two known receptors, adiponectin receptors (ADIPOR) 1 and 2. We examined the association between polymorphisms of ADIPOR1 and ADIPOR2 and bone mineral density (BMD) in postmenopausal Korean women. Six polymorphisms in ADIPOR1 and four polymorphisms in ADIPOR2 were selected and genotyped in all study participants (n = 1,329). BMD at the lumbar spine and femur neck were measured using dual-energy X-ray absorptiometry. Lateral thoracolumbar (T4-L4) radiographs were obtained for vertebral fracture assessment and the occurrence of non-vertebral fractures examined using self-reported data. P values were adjusted for multiple testing using Bonferroni correction (P(corr)). ADIPOR1 rs16850799 and rs34010966 polymorphisms were significantly associated with femur neck BMD (P(corr) = 0.036 in the dominant model; P(corr) = 0.024 and P(corr) = 0.006 in the additive and dominant models, respectively). Subjects with the rare allele of each polymorphism had lower BMD, and association of rs34010966 with BMD showed a gene dosage effect. However, ADIPOR2 single nucleotide polymorphisms and haplotypes were not associated with BMD at any site. Our results suggest that ADIPOR1 polymorphisms present a useful genetic marker for BMD in postmenopausal Korean women. 相似文献
6.
Application of a UPLC‐MS/MS method for the analysis of alosetron in human plasma to support a bioequivalence study in healthy males and females 下载免费PDF全文
Darshan V. Chaudhary Daxesh P. Patel Jaivik V. Shah Priyanka A. Shah Mallika Sanyal Pranav S. Shrivastav 《Biomedical chromatography : BMC》2015,29(10):1527-1534
A simple, rapid and sensitive ultra‐performance liquid chromatography–tandem mass spectrometry (UPLC‐MS/MS) method has been developed and validated for the determination of alosetron (ALO) in human plasma. The assay method involved solid‐phase extraction of ALO and ALO 13C‐d3 as internal standard (IS) on a LichroSep DVB‐HL (30 mg, 1 cm3) cartridge. The chromatography was performed on an Acquity UPLC BEH C18 (50 × 2.1 mm, 1.7 µm) column using acetonitrile and 2.0 mm ammonium formate, pH 3.0 adjusted with 0.1% formic acid (80:20, v/v) as the mobile phase in an isocratic mode. For quantitative analysis, the multiple reaction monitoring transitions studied were m/z 295.1/201.0 for ALO and m/z 299.1/205.1 for IS in the positive ionization mode. The method was validated over a concentration range of 0.01–10.0 ng/mL for ALO. Post‐column infusion experiment showed no positive or negative peaks in the elution range of the analyte and IS after injection of extracted blank plasma. The extent of ion‐suppression/enhancement, expressed as IS‐normalized matrix factor, varied from 0.96 to 1.04. The assay recovery was within 97–103% for ALO and IS. The method was successfully applied to support a bioequivalence study of 1.0 mg alosetron tablets in 28 healthy Indian male and female subjects. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
7.
G. C. Verghese R. Kishore V. P. Guinn 《Journal of Radioanalytical and Nuclear Chemistry》1973,15(1):329-335
Hair clippings (from the head) from over a hundred persons in and around Orange County of California were analysed for mercury,
gold, zinc, and copper by instrumental neutron activation analysis. The results of the study show significant differences
in the trace-element distributions between males and females. For mercury, the mode of the distribution occurs at about 1
to 1,5 ppm for males and 4 to 6 ppm for females. A significant difference between the male and female distribution curves
was also found for gold, and a less significant one for zinc and copper. This study indicates the possibility that the high
levels of mercury and gold in the hair of females are more likely due to external contamination, because of the more frequent
and intense exposure of their hair to cosmetics. Moreover, as females usually have longer hair, their hair strands are exposed
to such treatment over a longer period of time. Hair being a good ion-exchange material, trace elements are absorbed easily
during the process of washing and setting of hair, and accumulation of these over a long period may cause a very high concentration
of these elements. The variability of trace-element concentration as a result of external contamination, and the sometimes
marked variation along the length of the hair, pose a serious problem in forensic work. Identification criteria should provide
for these variations, especially in the case of mercury and gold. This work also indicates that if the evidence hair from
the scene of a crime does not contain the root end, its value as an evidence specimen is considerably reduced. 相似文献
8.
WU Qing-tian MA Qing-jie HE Cheng-yan WANG Cai-xia GAO Shi HOU Xia MA Tong-hui 《高等学校化学研究》2007,23(3):297-299
An overt phenotype of aquaporin-1 knockout(AQP1 ko) mice is growth retardation, suggesting possible defects in bone development and metabolism. In the present study, we analyzed the bone mineral density(BMD), bone calcium and phosphorus contents, and bone metabolism in an AQP1 ko mouse model. The BMD of femurs in AQP1 ko mice was significantly lower than that of litter-matched wildtype mice as measured by dual energy X-ray absorptiometry. Consistently, the contents of bone total calcium and phosphorus were also significantly lower in AQP1 ko mice. The reduced BMD caused by AQP1 deficiency mainly affect male mice. Bone metabolic activity, as indicated by 99mTc-MDP absorption measurements, was remarkably reduced in AQP1 ko mice. These results provide the first evidence that AQP1 play an important role in bone structure and metabolism. 相似文献
9.
《Journal of membrane science》2002,210(1):65-75
The current density distribution in a seawater electrodialyzer is approximated by a quadratic equation. The equation is solved using a three-dimensional simultaneous equation, and the current density distribution and the coefficients expressing the current density distribution are calculated. The method for estimating the limiting current density and the saturation current density of an electrodialyzer is established using the current density distribution coefficients. Electrodialytic conditions (current density, solution velocity and electrolyte concentration in desalting cells, the thickness and flow-pass length of a desalting cell, the standard deviation of the solution velocity ratio in desalting cells and the overall osmotic coefficient of a membrane pair) versus the current density distribution coefficients, limiting current density and saturation current density are obtained. Electrodialytic conditions at which current density reaches the limiting current density or saturation current density are determined. 相似文献
10.
Heiko Jacobsen 《Journal of computational chemistry》2009,30(7):1093-1102
Stalke's dilemma, stating that different chemical interpretations are obtained when one and the same density is interpreted either by means of natural bond orbital (NBO) and subsequent natural resonance theory (NRT) application or by the quantum theory of atoms in molecules (QTAIM), is reinvestigated. It is shown that within the framework of QTAIM, the question as to whether for a given molecule two atoms are bonded or not is only meaningful in the context of a well‐defined reference geometry. The localized‐orbital‐locator (LOL) is applied to map out patterns in covalent bonding interaction, and produces results that are consistent for a variety of reference geometries. Furthermore, LOL interpretations are in accord with NBO/NRT, and assist in an interpretation in terms of covalent bonding. © 2008 Wiley Periodicals, Inc.J Comput Chem, 2009. 相似文献
11.
12.
谢永红 《中国无机分析化学》2021,11(1):36-38
矿泉水界限指标中的四种矿物质元素锌、锂、锶、偏硅酸(以H2SiO3计),国标方法需每种元素分别测定且步骤繁琐,本实验采用ICP-OES对矿泉水中这4种元素的含量进行同时测定,四种元素的检出限在0.01~0.10 mg/L,对市售矿泉水进行了检测,加标回收率在83 %~100 %,相对标准偏差为0.31 %~1.96 %,方法简便省时,精密度和准确度较高,可以作为一种鉴别矿泉水品质的方法。 相似文献
13.
The spectrochemical behavior of nonvolatile tungsten and boron was tested by adding different buffers and using 12 A ac arc excitation. The oxidization and sulfidization processes were found to be most effective for facilitating the volatilization. The optimal admixture was the copper oxide buffer for both the detection limit and the precision of the method. The reference values of the background or a palladium line blackening were used. 相似文献
14.
E. Taskaev 《Journal of Radioanalytical and Nuclear Chemistry》1987,118(5):319-322
Rubidium and cesium were determined in underground mineral waters and sea lye by precipitation with sodium tetraphenyl borate followed by neutron activation. The short lived nuclides86mRb and134mCs were used for the analysis. 相似文献
15.
纳米磷酸钙在自然界骨组织的形成过程中起到了关键作用。尽管骨的类型有所不同,但在其初级结构中的无机成分都是纳米磷酸钙。纳米磷酸钙结构能够给予骨良好的机械性能和生物学活性。在生物体中,无机纳米磷酸钙在有机基质的调控下能定向自组装成特定的生物矿物。体外细胞实验显示小尺寸纳米羟基磷灰石更能促进骨髓基质干细胞的增殖,而同尺寸的结晶型纳米磷酸钙则比无定形磷酸钙更能利于干细胞分化。鉴于纳米磷酸钙具有很好的生物相容性和骨诱导性,可以发展成为理想的生物材料常用于骨组织工程和生物医学。 相似文献
16.
Ming H. Zheng K. Hinterkeuser K. Solomon V. Kunert N. J. Pavlos J. Xu 《Macromolecular Symposia》2007,253(1):179-185
Summary: We have analyzed a number of collagen-derived biomaterials for the matrix- induced and assisted bone and cartilage tissue regeneration. These include the Small intestine submuosa (SIS) Restor ™, ACI-Maix collagen membrane, Chondro- Gide collagen membrane, Permacol collagen Ossix and lycoll collagen membrane and five types of collagen-based marine sponge skeletons. Certain characteristics of different scaffold materials with comparable chemical composition may vary significantly. This variation may have a relevant impact on the suitability of the scaffolds for bone and cartilage regeneration. It suggests that the ACI-Maix® membrane is the best available collagen-derived material for an MACI®/MACT® application. In addition, the study of marine sponge indicates that the collagenous fibre skeleton of marine sponges provides a suitable bioscaffold for bone regeneration, as it supports the adhesion, migration and proliferation of osteoblasts in vitro. 相似文献
17.
纳米磷酸钙在自然界骨组织的形成过程中起到了关键作用。尽管骨的类型有所不同,但在其初级结构中的无机成分都是纳米磷酸钙。纳米磷酸钙结构能够给予骨良好的机械性能和生物学活性。在生物体中,无机纳米磷酸钙在有机基质的调控下能定向自组装成特定的生物矿物。体外细胞实验显示小尺寸纳米羟基磷灰石更能促进骨髓基质干细胞的增殖,而同尺寸的结晶型纳米磷酸钙则比无定形磷酸钙更能利于干细胞分化。鉴于纳米磷酸钙具有很好的生物相容性和骨诱导性,可以发展成为理想的生物材料常用于骨组织工程和生物医学。 相似文献
18.
Unfilled natural rubber compounds composed of conventional (CV), semi-efficient (SEV), efficient (EV) and sulfur donor (SD) vulcanization systems were heat aged to promote sulfur reversion. Rheometry, hardness, strain-strain characteristics including Mooney-Rivlin analysis, equilibrium solvent swell and Double Quantum (DQ) Nuclear Magnetic Resonance (NMR) were used to monitor crosslink density changes. A loss of crosslink density was observed by rheometry, C1, equilibrium swelling and by DQ NMR as a function of cure extent. No chain scission reactions were operating in the time/temperature conditions used. All crosslink distributions were unimodal and the network homogeneity followed the order of EV > SD > SEV > CV. The crosslink distribution narrowed during the curing process for the CV and SEV systems. Non-oxidative maturation reactions were advantageous in promoting a more random distribution of crosslinks in the polymer matrix. 相似文献
19.
Gordon K. Pagenkopf William Brady Judy Clampet Michael A. Purcell 《Analytica chimica acta》1978,98(1):177-179
The interaction of [PdCl4]2-aqwith ethylene-bis(thioglycolic) acid (EBTGA) and β-ethylthioethylene(thioglycolic) acid (β-ETETGA), has been interpreted and evaluated quantitatively. The successive constants of palladium(II) with EBTGA and/or β-ETETGA in acid medium have been determined spectrophotometrically. 相似文献
20.
K. A. Sabirov L. V. Marinina Kh. M. Kamilov A. Sh. Karabaev T. U. Rakhmatullaev M. M. Adakhamov 《Chemistry of Natural Compounds》1991,27(5):612-614
The mineral composition of phytin has been studied as a function of the variety of the source of raw material and the possibility
of its change during the process of isolation.
All-Union Scientific-Research Chemical and Technological Institute of the Medicinal Industry, Tashkent. Translated from Khimiya
Prirodnykh Soedinenii, No. 5, pp. 695–698, September–October, 1991. 相似文献