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111.
Several recent studies have revealed a wide role for nitric oxide (NO) in bone metabolism. Low doses of NO cause bone resorption, but higher doses of NO inhibit bone resorbing activity. Cytokines are potent stimulators of NO production. NO is a very short-lived molecules. It exists for only 6-10 s only before it is converted by oxygen and water into the end-products nitrates and nitrites. Osteoporosis is a metabolic bone disease, characterized by a decreased amount of bone and increased susceptibility to fracture. NO may be involved as a mediator of bone disease such as post-menopausal osteoporosis. Calcitonin is a peptide hormone that inhibits bone resorption. The function of calcitonin in some cells is often unclear. In this study 30 post-menopausal osteoporotic women of ages ranging between 55 and 59 years without systemic diseases and free of any drug therapy were included. Twenty of them, randomly chosen, were treated with calcium (500 mg day(-1))+calcitonin (nasal spray 100 U day(-1)) and the other 10 women (control group) were treated with calcium only. This treatment was applied for 6 months and NO values were measured in each of the two groups before and after treatment. Our findings demonstrate that NO regulates osteoclastic bone resorption activity in association with calcitonin. 相似文献
112.
Two new coumarin glycosides (1 and 2) along with two known coumarin glucosides, daphnin (3) and daphnetin glucoside (4) were isolated from the aerial parts of Cruciata taurica. The structures of the new compounds were elucidated by spectral methods and chemical means as 7-O-(6' -acetoxy-beta-D-glucopyranosyl)-8-hydroxycoumarin (1) and 7-O-[6 '-O-(3',4'-dihydroxycinnamoyl)-beta-D-glucopyranosyl]-8-hydroxycoumarin (2). The phylogenetic significance of coumarins in C. taurica was discussed. 相似文献
113.
Azaz D Demirci F Satil F Kürkçüoğlu M Başer KH 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(9-10):817-821
The genus Satureja is represented by fifteen species of which five are endemic and Satureja pilosa and S. icarica have recently been found as new records for Turkey. Aerial parts of the Satureja pilosa, S. icarica, S. boissieri and S. coerulea collected from different localities in Turkey were subjected to hydrodistillation to yield essential oils which were subsequently analysed by GC and GC/MS. The main constituents of the oils were identified, and both antibacterial and antifungal bioassays were applied. Carvacrol (59.2%, 44.8%, 42.1%) was the main component in the oils of S. icarica, S. boissieri and S. pilosa, respectively. The oil of S. coerulea contained beta-caryophyllene (10.6%) and caryophyllene oxide (8.0%) as main constituents. 相似文献
114.
Ozipek M Saracoglu I Ogihara Y Caliş I 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(7-8):603-608
A new nuatigenin-type steroidal saponin, multifidoside (2), was isolated from the aerial parts of Veronica fuhsii and V multifida and its structure was identified as 3-O-([alpha-L-rhamnopyranosyl-(1-->2glu)]-[beta-D-glucopyranosyl-(1-->4rha)-alpha-L-rhamnopyranosyl (1-->4glu)]-beta-D-glucopyranosyl]nuatigenin 26-O-beta-D-glucopyranoside. Additionally, a known steroidal saponoside, aculeatiside A (1), from V. fuhsii, a phenylethanoid glycoside, verpectoside A (3), and a flavon glycoside, isoscutellarein 7-O-(2"-O-6"-O-acetyl-beta-D-allopyranosyl-beta-D-glucopyranoside) (4) from V. multifida were isolated. 相似文献
115.
Kamenarska Z Yalçin FN Ersöz T Caliş I Stefanov K Popov S 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(7-8):584-590
The chemical composition of the brown alga Cystoseira crinita Bory from the Eastern Mediterranean was investigated. Fourteen sterols have been identified, five of them for the first time in algae. The structure of one new sterol was established. The origin of seven sterols with short side chains was discussed. In the volatile fraction 19 compounds and in the polar fraction 15 compounds were identified. The main lipid classes were isolated and their fatty acid composition was established. 相似文献
116.
Caliş I Kirmizibekmez H Tasdemir D Sticher O Ireland CM 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(7-8):591-596
From the methanolic extract of the underground parts of Globularia orientalis, a new antioxidant sugar ester was isolated. The structure of the new compound, globularitol (1), was identified as 6-O-feruloyl-beta-D-glucopyranosyl-(1-->6)-glucitol by spectroscopic methods (1D and 2D NMR, ESI- and FAB-MS) and confirmed by chemical means. 相似文献
117.
A new enzyme electrode for the determination of alcohols was developed by immobilizing alcohol oxidase in polvinylferrocenium matrix coated on a Pt electrode surface. The amperometric response due to the electrooxidation of enzymatically generated H(2)O(2) was measured at a constant potential of +0.70 V versus SCE. The effects of substrate, buffer and enzyme concentrations, pH and temperature on the response of the electrode were investigated. The optimum pH was found to be pH 8.0 at 30 degrees C. The steady-state current of this enzyme electrode was reproducible within +/-5.0% of the relative error. The sensitivity of the enzyme electrode decreased in the following order: methanol>ethanol>n-butanol>benzyl alcohol. The linear response was observed up to 3.7 mM for methanol, 3.0 mM for ethanol, 6.2 mM for n-butanol, and 5.2 mM for benzyl alcohol. The apparent Michaelis-Menten constant (K(Mapp)) value and the activation energy, E(a), of this immobilized enzyme system were found to be 5.78 mM and 38.07 kJ/mol for methanol, respectively. 相似文献
118.
119.
Dündaröz MR Türkbay T Sarici SU Akay C Sayal A Denli M 《Biological trace element research》2002,88(2):119-123
Plasma and erythrocyte levels of selenium (Se) and zinc (Zn) have not been investigated in volatile (inhalant) substance abusers
previously, although changes in the activities of antioxidant enzymes resulting from oxidative damage caused by various constituents
of volatile substances have been shown in a few animal and human studies. Concentrations of these two elements in erythrocytes
and plasma of 37 adolescents with inhalant abuse were measured by atomic absorption spectrophotometry and compared with those
of 37 age-matched healthy controls. Erythrocyte and plasma levels of Se and plasma level of Zn were significantly lower in
the study group when compared to the control group. Chronic inhalation of volatile substances can decrease the plasma levels
of Se and Zn and, thus, may lead to a decrease in the activity of antioxidant enzyme systems in adolescent abusers. The role
of Se and Zn supplementation in children with inhalant abuse remains to be determined considering the reduced antioxidant
activity resulting from deficiency of these trace elements. 相似文献
120.
Işcan M Ada AO Coban T Kapucuoğlu N Aydin A Isimer A 《Biological trace element research》2002,89(2):177-190
When male rats were given a single dose of cadmium (Cd) (3.58 mg CdCl2·H2O/kg, ip) 72 hr prior to sacrifice, the testicular 7-ethoxyresorufin O-deethylase (EROD) and glutathione S-transferase (GST) activities toward the substrates 1-chloro-2,4-dinitrobenzene (CDNB), 1,2-dichloro-4-nitrobenzene (DCNB),
ethacrynic acid (EAA), 1,2-epoxy-3-(p-nitrophenoxy)-propane (EPNP), and cumene hydroperoxide (CHPx) decreased significantly as compared to controls. Cd also inhibited
reduced glutathione (GSH) level while increasing the lipid peroxidation (LP) level significantly. When the animals were given
a single dose of nickel (Ni) (59.5 mg NiCl2·6H2O/kg, ip) 16 hr prior to sacrifice, significant decreases were observed in EROD and GST activities toward CDNB, EAA, EPNP,
and CHPx, and GSH level. No significant alterations were noted in DCNB GST activity and LP level by Ni. For the combined treatment,
rats received the single dose of Ni 56 hr after the single dose of Cd and were killed 16 hr later. In these animals, lesser
depressions were observed on EROD activity and LP level than those of Cd alone. The combination of metals significantly inhibited
GST activities and GSH level but not to a greater degree than noted by Cd or Ni alone. Plasma testosterone levels of Cd-,
Ni-, and combination-treated rats decreased significantly compared to controls. The strongest depression was achieved by Cd
alone. Cd, both alone and in combination with Ni, increased the tissue Ni uptake significantly. Ni, however, did not produce
such an effect on the tissue uptake of Cd in either case. Cd treatment caused interstitial edema and coagulation necrosis
in seminiferous tubules and also caused fibrinoidal necrosis in vascular endothelium. Ni treatment did not produce any pathological
testicular alterations compared to controls. Combined treatment produced fewer pathological alterations (i.e., only interstitial
edema) than that of Cd treatment. These results reveal that the combination of Cd and Ni does not have a synergistic effect
on testicular xenobiotic metabolizing enzymes, and in contrast, Ni has an ameliorating effect on pathological disturbances
caused by Cd alone in the rat testis. 相似文献