Silicon nanowires and nanoneedles show promise for many device applications in nanoelectronics and nanophotonics, but the remaining challenge is to grow them at low temperatures on low-cost materials. Here we present plasma-enhanced chemical vapor deposition of crystalline/amorphous Si nanoneedles on glass at temperatures as low as 250 °C. High resolution electron microscopy and micro-Raman spectroscopy have been used to study the crystal structure and the growth mechanism of individual Si nanoneedles. The H(2) dilution of the SiH(4) plasma working gas has caused the formation of extremely sharp nanoneedle tips that in some cases do not contain a catalytic particle at the end.
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A total of 2,232 bovine embryos was obtained from 294 flushings at a commercial embryo transfer operation. The embryos were frozen in groups from individual flushings using 0.25-cc straws and a conventional freezing procedure with glycerol as a cryoprotective agent. The embryos were stored in liquid nitrogen for up to 28 months. Sucrose was used for the removal of glycerol after the thawing of embryos. The thawed embryos were then examined morphologically, and 1,097 embryos (49%) with no apparent defects were used for subsequent transfer. The viability of the thawed embryos from the individual flushes was evaluated in relationship to the length of cryopreservation. No correlation (P>0.1) was found between the two parameters in embryos from superovulations with above and below average yields. This finding was further confirmed in a proportion of the embryos by the evaluation of pregnancy rates. Thus, neither the typical length of embryo storage in a commercial operation nor the success of superovulation influenced the survival rate of embryos after thawing based on morphological criteria and pregnancy rates.
- Publikační typ
- časopisecké články MeSH
- MeSH
- corpus luteum patofyziologie MeSH
- nemoci ovaria krev patofyziologie MeSH
- nemoci skotu krev patofyziologie MeSH
- progesteron krev MeSH
- skot MeSH
- ženská infertilita krev patofyziologie veterinární MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- Názvy látek
- progesteron MeSH
For a period of 70 days, young gilts were given rations containing a commercial mixture of polychlorinated biphenyls (PCB), produced in Czechoslovakia (Delor 105). One group of animals (A) was given feed containing 10 mg chlorobiphenyls per kg, the other group (B) was given feed containing 50 mg chlorobiphenyls per kg; on the whole, each animal of group A got 1 g of PCB mixture and each animal of group B 5 g. In about the mid-time of the experiment and before its termination the animals were given an i. m. injection of progesterone; then the animals were studied for the changes in the concentration of blood plasma progesterone. Statistically significant (P less than 0.05) and highly significant (P less than 0.01) differences in the values of the biological half-life of progesterone were found between the group of PCB-treated animals and the control group, and between groups A and B.
- MeSH
- polychlorované bifenyly škodlivé účinky MeSH
- prasata krev MeSH
- progesteron aplikace a dávkování krev MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- Názvy látek
- polychlorované bifenyly MeSH
- progesteron MeSH
The activity of luteinizing hormone (LH) in serum gonadotropin (PMSG) was studied by a bioassay in vitro, using the cells of mouse testes prepared by the combination of enzymatic and mechanical diffociation. The activity of individual preparations was calculated according to the amount of produced testosterone measured by radioimmunoassay. Comparison with the 2nd international standard of PMSG (WHO) showed that in the PMSG substandard (Dessau) the activity of LH was twice lower, and in three charges of the commercial PMSG preparation (Bioveta, Ivanovice in Haná) four-and-a-half times lower than declared. No great variability of LH activity was observed among the charges of the commercial PMSG preparation.
- MeSH
- biotest metody MeSH
- gonadotropiny koňské analýza MeSH
- luteinizační hormon analýza MeSH
- myši MeSH
- techniky in vitro MeSH
- testis metabolismus MeSH
- testosteron biosyntéza MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- Názvy látek
- gonadotropiny koňské MeSH
- luteinizační hormon MeSH
- testosteron MeSH
The cells of the testes of mice were enzymatically separated and the amount of Leydig cells was determined in different stages of dispersion and after washing the separated tissue. This amount ranged from 2 to 9%. The largest quantity of Leydig cells (9%) was obtained when separated tubuli were washed. The response of cell suspensions at seven concentrations stimulated by human chorion gonadotrophin (HCG) was tested. Cell suspension concentrations from 5.3 x 10(5) to 1.4 x 10(6) cells/ml were found to be satisfactory. After two to three hours of incubation, the values of testosterone could be used for the determination of the activity of gonadotropic preparations.
- MeSH
- časové faktory MeSH
- kultivované buňky MeSH
- Leydigovy buňky cytologie MeSH
- myši MeSH
- počet buněk MeSH
- testis cytologie metabolismus MeSH
- testosteron biosyntéza MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- Názvy látek
- testosteron MeSH
The ability of mouse testicular tissue to respond to stimulation by a commercial preparation of human choriongonadotropin (Praedyn Spofa) was tested in vitro, using whole testes, fragments and cell suspension. In each experiment seven gonadotropin concentrations ranging from 0.06 to 50 i. u. per litre were tested, and the results were compared with the group of control samples without gonadotropin. The incubation of whole testes with gonadotropin of different concentrations was performed in five vessels, each containing one testis; the fragments were incubated in four vessels, each containing four fragments from different testes, and the cell suspension in triplicates containing 1 . 10(6) cells per ml. All three types of tissue reacted to the increasing concentrations of stimulating agent by the increasing production of testosterone, the concentration of which was determined by radioimmunoassay. For the suppression of the individuality and for achieving a uniform response of the individual samples with each stimulation, the cell suspension of testes from several animals appears to be most suitable.
- MeSH
- biotest metody MeSH
- choriogonadotropin analýza farmakologie MeSH
- myši MeSH
- radioimunoanalýza MeSH
- techniky in vitro MeSH
- testis metabolismus MeSH
- testosteron biosyntéza MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- Názvy látek
- choriogonadotropin MeSH
- testosteron MeSH
The effectiveness of GnRH (Luliberin) and goat anti-PMSG serum prepared at the Veterinary Research Institute, Brno, was studied during the superovulation of heifers treated with PMSG and Estrumate. The use of GnRH did not exert any positive influence on superovulation, as compared with the control groups,. when anti-PMSG serum was administered five hours from the determined beginning of oestrus (46-53 hours from the first administration of Estrumate), the length of oestrus was reduced in comparison with the control group (25.8 and 51.3 h), the number of 22.3). The tested heifers produced 17.8 ova, on an average, out of which (4.1 and 22.3). The tested heifers produced 17.8 ova, on an average, out of which 12.5 were good-quality embryos. The control heifers produced 6.9 ova including 2.9 embryos. The obtained results provide convincing evidence of the promising results of the use of goat anti-PMSG serum during the superovulation cattle.
- MeSH
- gonadotropiny koňské imunologie MeSH
- hormony uvolňující hypofyzární hormony farmakologie MeSH
- kozy MeSH
- ovulace účinky léků MeSH
- protilátky aplikace a dávkování MeSH
- skot fyziologie MeSH
- superovulace účinky léků MeSH
- těhotenství MeSH
- zvířata MeSH
- Check Tag
- skot fyziologie MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- Názvy látek
- gonadotropiny koňské MeSH
- hormony uvolňující hypofyzární hormony MeSH
- protilátky MeSH
Sixteen heifers were superovulated using 5 000 i.u. PMSG on days 9 to 11 of the oestrous cycle (day 1 of the experiment) followed by two injections of 500 mug Estrumate 48 and 54 hours later. Eight of them were injected with goat anti-PMSG serum 5 hours after the first signs of oestrus were observed. Compared with the control group, the treatment with anti-PMSG serum resulted in a shorter heat period (25.8 vs. 51.3 hours), a higher mean number of ovulations (22.1 vs. 18.0) and a lower number of follicles over 10 mm in diameter (4.1 vs. 22.3). The mean numbers of eggs recovered in the experimental and control groups were 17.8 and 6.9, of which 70.2 and 42.0 per cent, respectively, were viable embryos. The concentrations of progesterone and 17-beta oestradiol in the blood plasma showed no significant differences between the experimental and control animals. A higher oestradiol in the control group on day 9 of the experiment was in keeping with the histological picture of the target organs and with a significantly higher number of follicles at slaughter on days 12 to 14 of the experiment.
- Publikační typ
- časopisecké články MeSH
In intact boars, intravenous administration of 100 to 6000 I. U. chorionic gonadotropin elicited a pronounced rise in the plasma level of testosterone, depending on the time interval from the administration of chorionic gonadotropin and on the size of the administered dose. In the blood of castrated boars such an application of choronic gonadotropin did not influence the concentration of testosterone. It was inferred that the rise in the levels of blood testosterone in boars after administration of chorionic gonadotropin was specific for testicular incretion and indicated the endocrine reserve of the testes. There is a discussion concerning the importance of the functional testing of the incretion capacity of testes for differential diagnosis different forms o incretion hypogonadism.
- MeSH
- choriogonadotropin aplikace a dávkování MeSH
- injekce intravenózní MeSH
- prasata krev MeSH
- testis účinky léků MeSH
- testosteron krev MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- Názvy látek
- choriogonadotropin MeSH
- testosteron MeSH
