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121.
Elghazali M Barezaik IM Abdel Hadi AA Eltayeb FM Al Masri J Wasfi IA 《Veterinary journal (London, England : 1997)》2008,178(2):272-277
The pharmacokinetics of tramadol in camels (Camelus dromedarius) were studied following a single intravenous (IV) and a single intramuscular (IM) dose of 2.33 mg kg(-1) bodyweight. The drug's metabolism and urinary detection time were also investigated. Following both IV and IM administration, tramadol was extracted from plasma using an automated solid phase extraction method and the concentration measured by gas chromatography-mass spectrometry (GC/MS). The plasma drug concentrations after IV administration were best fitted by an open two-compartment model. However a three-compartment open model best fitted the IM data. The results (means+/-SEM) were as follows: after IV drug administration, the distribution half-life (t(1/2)(alpha)) was 0.22+/-0.05 h, the elimination half-life (t(1/2)(beta)) 1.33+/-0.18 h, the total body clearance (Cl(T)) 1.94+/-0.18 L h kg(-1), the volume of distribution at steady state (Vd(ss)) 2.58+/-0.44 L kg(-1), and the area under the concentration vs. time curve (AUC(0-infinity)) 1.25+/-0.13 mg h L(-1). Following IM administration, the maximal plasma tramadol concentration (C(max)) reached was 0.44+/-0.07 microg mL(-1) at time (T(max)) 0.57+/-0.11h; the absorption half-life (t(1/2 ka)) was 0.17+/-0.03 h, the (t(1/2)(beta)) was 3.24+/-0.55 h, the (AUC(0-infinity)) was 1.27+/-0.12 mg h L(-1), the (Vd(area)) was 8.94+/-1.41 L kg(-1), and the mean systemic bioavailability (F) was 101.62%. Three main tramadol metabolites were detected in urine. These were O-desmethyltramadol, N,O-desmethyltramadol and/or N-bis-desmethyltramadol, and hydroxy-tramadol. O-Desmethyltramadol was found to be the main metabolite. The urinary detection times for tramadol and O-desmethyltramadol were 24 and 48 h, respectively. The pharmacokinetics of tramadol in camels was characterised by a fast clearance, large volume of distribution and brief half-life, which resulted in a short detection time. O-Desmethyltramadol detection in positive cases would increase the reliability of reporting tramadol abuse. 相似文献
122.
Seyed Abdolreza Kazemeini Mohmmad Jafar Bahrani Hadi Pirasteh-Anosheh Seyed Mohammad Mehdi Momeni 《Archives of Agronomy and Soil Science》2013,59(11):1543-1552
Determining the proper rate of wheat residues incorporation into the soil under a wheat–maize double cropping system is an important issue in southern parts of Iran, where these two irrigated crops are consecutively grown. A 2-year experiment (2010–2011) was conducted to evaluate the effect of wheat residue incorporation rates (25%, 50% and 75%) and irrigation intervals (12, 16 and 20 days) on yield and growth of maize under no-tillage system compared to control without residue and under conventional tillage (CT) at the College of Agriculture, Shiraz University, Shiraz, Iran. The experiment was conducted as a split plot arranged in randomized complete block design with three replications. The results showed that increased irrigation intervals reduced the plant height (14.6%), leaf-area index (12.9%), rows (10.1%) and grains per ear (29.8%), thousand grain weight (6.9%), grain (33.8%) and biological yield (24.2) and harvest index (23.2%). Water deficit had no significant effect on soil organic matter and carbon-to-nitrogen ratio. Under 12 and 20 days irrigation intervals, the highest grain yields were obtained with 12.7 and 8.6 t ha?1 in CT and 25% residue incorporation into soil, respectively. Therefore, according to the results of this 2-year study, realized incorporation of 25% wheat residue soil covering percentage is recommended for this area with limited water resources. 相似文献
123.
124.
Hadi Atashi Mohammad Javad Zamiri Mohammad Bagher Sayyadnejad Amir Akhlaghi 《Tropical animal health and production》2012,44(8):2001-2006
The study was undertaken to determine the trends in the reproductive performance of Holstein dairy cows in Iran during 1994 to 2008. Reproductive performance data for 528,034 lactations of 246,132 cows in 1,822 Holstein dairy herds of Iran were used. The potential effect of calving season, herd, parity, calving year, as well as herd size and 305-day milk production on reproductive performance traits was investigated using multiple regression models. The least squares means of age at first calving decreased by 3.1 (±0.06) days per year from 806.5 (±96.3) days in 1994 to 788 (±89.9) days in 2008. The least squares means of calving interval increased 1.02 (±0.03) days per year from 394.1 (±65) days in 1994 to 413.2 (±81) days in 2008. Greater 305-day milk production was associated with an average increase of 6.55 (±0.08) days in calving interval per 1,000-kg increase in milk yield. Larger herd size was associated with an average decrease of 0.22 (±0.02) days in calving interval per 50 cows per herd. The mean number of days dry was 88.6 (±51.3) days and increased by 0.82 (±0.02) days per year. In conclusion, reproductive performance in Holstein dairy herds has generally decreased, whereas herd size and milk production have increased over time. Producers may make significant improvements in herd reproduction by reviewing management strategies including the sire selection, reproductive management, inseminator training and techniques, and improved estrous detection. Moreover, it may be advisable for the fertility traits to be included in the genetic selection indices to reduce the rate of reproductive decline. 相似文献
125.
Asghar Tarmian Romain Remond Hadi Dashti Patrick Perré 《Wood Science and Technology》2012,46(1-3):405-417
The moisture diffusion coefficient of compression wood in spruce (P. abies) and tension wood in beech (F. sylvatica) was examined. The results indicated that the diffusion coefficient measured under steady-state condition (cup method) could well characterize the drying kinetics of the reaction woods. The compression wood offered more resistance to the moisture diffusivity when compared with the corresponding normal wood. The thick cell wall rich in lignin explains the small mass diffusivity in compression wood. In contrast, the mass diffusivity in beech is almost always higher in tension wood than in normal wood, in spite of similar density values. The high moisture diffusion in tension wood can be explained by the ease of bound water diffusion in the gelatinous layers (G-layers). 相似文献
126.
The films produced from pure starch are brittle and difficult to handle. Chemical modifications (e.g. cross-linking) and using a second biopolymer in the starch based composite have been studied as strategies to produce low water sensitive and relatively high strength starch based materials. A series of corn starch films with varying concentrations (0-20%, W/W) of citric acid (CA) and carboxymethyl cellulose (CMC) were produced by casting method. The effects of CA and CMC on the water vapor permeability (WVP), moisture absorption, solubility and tensile properties were investigated. The water vapor barrier property and the ultimate tensile strength (UTS) were improved significantly (p < 0.05) as the CA percentage increased from 0 to 10% (W/W). At the level of 15% (W/W) CMC, the starch films showed the lowest WVP values (2.34 × 10−7 g Pa−1 h−1 m−1) and UTS increased from 6.57 MPa for the film without CMC to 16.11 MPa for that containing 20% CMC. 相似文献
127.
Sayyed Mohammad Hadi Alavi Azadeh Hatef Constantinos C. Mylonas David Gela Maria Papadaki Marek Rodina Vojtech Ka?par Martin P?eni?ka Peter Podhorec Otomar Linhart 《Fish physiology and biochemistry》2012,38(6):1655-1666
Spermiation and changes in androgen (testosterone, T and 11-ketotestosterone, 11-KT) levels were studied in sterlet (Acipenser ruthenus) treated with GnRH agonist implants (dAla6-Pro9-LHRHa) at 25 and 75?μg?kg?1 b.w. and compared with those males treated with 4?mg?kg?1 b.w. of carp pituitary extract (CPE) and 3 pellets of Ovopel kg?1 b.w., which contains dAla6-Pro9NEt-mGnRH and metoclopramide. Sperm quality (sperm mass, spermatozoa concentration and sperm motility and velocity) was evaluated 24, 48 and 72?h after hormonal treatments. Males did not release sperm in the control group injected with physiological solution, while sperm could not be collected 7?days after treatments in all hormonally treated groups. Spermiation rates were 100?% in the CPE and Ovopel groups and 25–50?% in the GnRHa-treated groups. Sperm production was significantly lower in the GnRHa-treated groups than in the CPE and Ovopel groups and decreased 72?h after hormonal treatment. Sperm motility and velocity were higher in the Ovopel and GnRHa (75?μg) groups compared to the CPE and GnRHa (25?μg) groups and decreased 72?h after hormonal treatment. Androgens were only affected in spermiating males and changed in the Ovopel and GnRHa (75?μg) after hormonal treatment. Significant correlations were observed between sperm production, sperm motility and sperm velocity, but not androgens. The present study suggests involvement of dopamine in sturgeon spawning. Additionally, better sperm quality observed in the Ovopel group and particularly sperm motility in the GnRHa (75?μg) suggests enhancement of sperm quality in sturgeon treated with GnRHa. Therefore, further study is needed to induce fully spermiation using GnRHa implants in combination with a dopamine inhibitor. 相似文献
128.
Background: The effect of ovariectomy and accompanying sudden loss of circulating gonad hormones on spatial learning performance in the young adult rats was examined. We hypothesized that spatial learning and memory in a considerable number of women who undergo a surgical menopause and estrogen deprivation before their natural menopause be impaired. Methods: In this study, we used 26 Wistar rats (approximately five months of age) and divided them into two groups: intact and ovariectomized (OVX). They were tested for spatial reference memory in Morris water maze 6 weeks after OVX. Results: The results showed that the performance of OVX group in the water maze was significantly lower than the control group. Although, mean path length decreased across blocks in both groups, OVX rats had significantly longer path length than controls across blocks 2-6 (P<0.05). OVX rats had lower percent of total time spent in target quarter than controls in probe trials (P<0.05). Body weight gain was significant only in OVX group during the experiment (P<0.05). Plasma estrogen significantly decreased after OVX (P<0.05). Conclusion: This finding provides further evidence for the role of estrogen, a gonadal steroid hormone, in the manipulation of functions related to learning and memory. It is suggested that estrogen loss following OVX impaired spatial reference memory in young adult rats. Our results suggest that it is necessary to protect women who undergo a surgical menopause before their natural menopause from cognition impairments. 相似文献
129.
Bilehjani E Hakim SH Asl AA Vahdati SS Shahmohammadi G 《Pakistan journal of biological sciences: PJBS》2008,11(8):1176-1178
In a 64 year old man with dyspnea and palpitation and fatigue and non angina chest pain, we found all the Para clinics prefect but only it showed low HDL and a normocytic, normochromic anemia. In searching about cause of anemia, in bone marrow biopsy showed Paraproteinemia. Therefore false low HDL because of paraproteinemia, leads to miss-diagnosis of cardiovascular disease. 相似文献
130.
Effect of water management on greenhouse gas emissions and microbial properties of paddy soils in Japan and Indonesia 总被引:2,自引:1,他引:1
This research aims at elucidating the greenhouse gas emissions and its related soil microbial properties in continuously flooded
or intermittently drained paddy soils in Japan and Indonesia. The study in Japan comprises alluvial soil and peat, cultivated
to rice variety Nipponbare, while in Indonesia comprised alluvial soil cultivated to rice variety Siam Pandak. Intermittent drainage was performed to half number of the plot in 6 days interval, starting at tillering or heading stage
of rice, while the other half number of plot was kept flooded as control. The experiments were carried out to follow the randomized
block design with three replications. Gas samples were taken in weekly basis, except during the treatments (i.e., every 2 days
interval) and analyzed for methane (CH4) and nitrous oxide (N2O) concentrations. Soil samples were and analyzed for the population of methanogenic bacteria, denitrifiers, methane production
and consumption potentials, and methanogenic substrate. Plant growth parameters were also observed. The results showed that
intermittent drainage significantly reduced greenhouse gas emission from paddy soil of Indonesia and Japan without significant
changes in soil microbial population. The reductions of greenhouse emission from Japanese peaty and alluvial paddy soil due
to intermittent drained were about 32 and 37%, respectively. Meanwhile, the reductions in greenhouse gas emission from alluvial
soil of Indonesia due to intermittent drainage were very similar to that of in Japan, i.e., average about 37%. This suggests
that intermittent drainage can be an appropriate technology option to reduce the greenhouse gas emission from paddy soil in
Japan and Indonesia. 相似文献