Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 26

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  bone tissue
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
In this study we determined the levels of trace elements (zinc, copper, lead, cadmium and mercury) in three layers of bones of the hip joint (cartilage, compact bone and spongy bone) of 30 red foxes (Vulpes vulpes) from north-western Poland. Concentrations of Cu, Zn, Pb and Cd were determined by atomic absorption spectrophotometry (ICP-AES) in inductively coupled argon plasma using a Perkin-Elmer Optima 2000 DV. Determination of Hg concentration was performed by atomic absorption spectroscopy. In cartilage, compact bone and spongy bone samples from the red fox, median concentrations of the metals studied could be arranged in the following descending series: Zn > Cu > Pb > Cd > Hg, the values ranging from 142 to 0.002 mg/kg dw. There was a significant difference in Cu concentrations, among all the materials analyzed, with much more Cu found in spongy bone than in compact bone. Significant differences were also noted in the case of Hg concentrations in cartilage with compact bone and the spongy bone, and between concentrations of this metal in compact bone and spongy bone. In males, the concentration of Hg in spongy bone was greater than in females. Younger foxes had a higher concentration of this metal in cartilage than adults. The strongest synergistic relationships were observed in spongy bone between the Zn and Cu, Zn and Cd, as well as between Cu and Cd. Statistically significant antagonistic relationships were detected between zinc and lead in compact bone. In addition to monitoring studies conducted on the abiotic environment, an urgent need exists for long-term monitoring of concentrations of heavy metals with long-term effects on living organisms. An important addition is provided by biomonitoring studies on domesticated and free-living mammals, including Canidae.
The bone mineral density (BMD) and the bone mineral content (BMC) in the bone tissue of the bilateral first phalanges of horses’ thoracic limbs were analysed. The research material consisted of isolated pastern bones derived from 22 horses. The research was conducted with the use of a Norland model Excell Plus densitometer (Fort Atkinson WI, USA), using affinited beam X-ray technology and an animal research programme (Research Scan, 3.9.6. version) at the following parameters: scanning resolution of 1.5 x 1.5 mm, scanning speed 60 mm/s. The differences between BMC and BMD values in bilateral first phalanges in the thoracic limbs in horses were found to be nonsignificant. It also appeared that there are statistically significant positive correlations between values of the left and right bone of both analysed variables.
The aim of the studies was to compare the Ht values and the content of Hb in blood, total protein. Na, K, Ca, inorganic P and Mg in blood serum and bone tissue in lambs born in different seasons. A higher (P≤0.05) Ht value, K and Ca content, and a lower total protein, Na, inorganic P and Mg content were found in the blood of lambs born in autumn. A higher (P≤0.05) content of Ca and Mg, but a lower of Na, K, and inorganic P were found in the bone tissue of lambs born in autumn compared to the content of those elements in spring born lambs. The type of lambs’ birth was of no effect on the content of macroelements examined in their bone tissue. No differences were found in Hb content and body weight in lambs born in selected seasons.
The core of the limb bone cortex of mammals and birds is made of rapidly deposited, fibro-lamellar bone tissue (also present in non-avian theropods), which is usually surrounded by an avascular outer circumferential layer (OCL) of slowly deposited parallel-fibered bone. We present the first comparative allometric study of the relative OCL thickness (expressed as a fraction of the diaphyseal radius) in modern birds. Body size explains 79% of the OCL variation in thickness, which is inversely correlated with size, that is, shows negative allometry (slope -0.799). This may explain the apparent absence of OCL in the ratites. Since the OCL is deposited at the end of growth, we propose that its relative thickness probably correlates with the amount of slow, residual growth, which our results suggest to be on the average larger in small birds.
The aim of the study was to determine the mechanical and geometric properties as well as bone tissue density of long bones in primiparous and multiparous dams of minks supplemented with ß-hydroxy ß-methylbutyrate (HMB) and/or 2-oxoketoglutarate (2-Ox) during gestation. Powdered 2-Ox was given at the daily dosage of 0.4 g/kg b.w. separately or simultaneously with HMB, which was administered at the daily dosage of 0.02 g/kg b.w. The study demonstrates for the first time that administration of 2-Ox and/or HMB to dams markedly influences bone tissue density and the mechanical and geometrical properties of mother's bones in minks. Moreover, it was demonstrated that the supplementation was more effective in the thoracic limb, which was comprehensively used in contrast to the pelvic limb. The mechanical parameters and bone tissue density significantly increased in the humerus in multiparous minks. Only such diet may provide satisfactory production results in the animals. Nutritional deficiencies occurring during pregnancies may trigger body's own reserves to cover the bone mass increase in developing foetuses and support milk production. This can prevent regeneration of dams' organisms, which negatively affects their reproductive performance. 2-Ox or HMB may be regarded as a protective metabolite when administered orally to minks, counteracting the negative influences of pregnancy and lactation periods on bones condition. Both simultaneous treatment with 2-Ox and HMB and their separate administration were equally effective.
A novel diagnostic method was adapted from studies in horses and humans to postmortal research on ostrich bones. The research made it possible to determine referential values in the method of digital analysis of a radiological image for the tibio-tarsal bone of the ostrich, following exposure to injuries. In the case of a computer-generated analysis of a radiological image, the optimal conditions for taking images were selected, along with their digital record and processing: 0.096 mm/pixel, 256 greyness level (8 bits), and scanning in BMP (a bitmap that is an open format of raster graphics, a block of bytes, which describes an image pixel by pixel). The research was conducted on the rectangular-shaped (160 x 320 points) spongy bone taken about 80 mm below the articular surface near the proximal metaphysis. The research allowed defining parameters of the spongious matrix of the tibio-tarsal bone of healthy 14-month-old ostriches. The average number of trabeculae on lines was 10.41 mm² for both sexes, the average volume was 2.21 %, the density of the trabeculation (the percentage of the surface covered with trabeculae) was 47.44 % for both sexes and the average width of the trabeculae was 0.23 mm. On the basis of the conducted calculations, it is possible to draw a conclusion that the average number of radiological trabeculae, the volume of the trabeculae, and their density do not differ significantly for cocks and hens.
Age changes of bone tissue and molar cementum, and formation of daily layers in dentin of incisors enable us to estimate age and maximum lifespan, season of birth, season of death, sexual maturation, sex in adults, and in combination with tetracycline prebaiting, movements and space distribution of rodents. In hibernating rodents, the hibernation zone formed in incisor dentin can be used to assess inter- and intra­population variations in seasonal activity and growth. This approach is illustrated by examples from the study of rodents of the genera Apodemus and Sicista.
The utility of biochemical markers of bone metabolism has not been proven in the diagnosis of metabolic diseases of the bone tissue; however they are widely used as a tools for treatment monitoring. Their serum concentrations are influenced by a number of factors, like gender, health status, anthropometric and environmental factors. All the factors listed above should be taken into consideration during clinical use. The aim of the study was to determine the reference values and evaluate the influence of environmental and anthropometric variables on biochemical markers of bone turnover for women from Lublin Region (Poland). Subjects of the study were 188 normal women aged 30-79, all residents of Lublin Region. Analysed markers of bone turnover were: osteocalcin (OC) and C-terminal cross-linking telopeptide of type I collagen (CTX-I), both assessed using ELISA method. All blood samples were taken and analyzed at the Clinical Chem. Laboratory and Patho-morphology Department at the Institute of Agricultural Medicine in Lublin. The lumbar spine (L2-L4) of all subjects was examined in a-p position using the dual X-ray absorptiometry-DXA (DPX-A LUNAR Corp.) at the Department of Metabolic and Degenerative Diseases of Bone Tissue of Institute of Agricultural Medicine in Lublin. Data pertaining to factors affecting bone tissue were collected using a specially prepared questionnaire. Serum levels of OC and CTX-I in women in every age range were different, generally increasing with age. Serum levels of OC and CTX-I in the analysed population strongly depended of both menopausal status and bone mineral density. In conclusion, this study demonstrates that age and menopausal status variations need to be considered when interpreting laboratory measurements of biochemical markers of bone metabolism.
The aim of the study was to compare haematological and biochemical indices and mineral composition of bone tissue in the 4th and 5th caudal vertebra of 14-day-old Blackheaded (n = 117) and Romney Marsh (n = 100) Iambs (LK < 27 mmol/1) whose mothers had received Vitazol AD₃E and Polfamix "O" from the 60th day of pregnancy. Ht, Hb, MCHC, TSP, urea, ALT, AST as well as Na, K, Ca, Pinorg, Mg were determined in serum and bone tissue. Racial differences in the studied indices were observed, which showed that the Blackheaded lambs had lower value of Ht and Hb (P≤0.01) and higher total protein content, AST activity (P≤0.05) and body weight as compared with the Romney Marsh lambs. No effects of the applied supplements were observed as to the concentration of macroelements in the serum of either breed. On the other hand, the Blackheaded lambs, whose mothers had received Pofamix "O" during pregnancy, demonstrated higher (P≤0.05) concentration of bone tissue calcium (24.05 mmol/l in 1 g of dry weight) in comparison with control lambs (21.47 mmol/l in I g of dry weight). In the Romney Marsh lambs, the application of Vitazol AD₃E resulted in higher (P≤0.05) calcium concentration (23 .46 mmol/l in 1 g of dry weight) and higher (P≤0.05) ratio of Ca to P ( 1.59: 1) in bone tissue compared with the control lambs (respectively 19.96 mmol/l in 1 g of dry weight and 1.17: 1).
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.