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91.
Plant genotypes with higher drought tolerance through improved root characteristics are poorly studied in orchardgrass. In the current research, 30 orchardgrass genotypes were polycrossed and the resulting half‐sib families evaluated under both normal and water stress environments. Under water stress conditions, values for most root traits decreased at 0–30 cm soil depth, while at 30–60 cm depths, the root length (RL), root area (RA), root volume, percentage of root dry weight (RDW) and the ratio of root to shoot were increased. We identified drought‐tolerant genotypes with a high combining ability for root characteristics and a high yield potential. High estimates of heritability as well as genetic variation for root traits indicated that phenotypic selection would be successful in order to achieve genetic progress. Indirect selection to improve dry matter yield was most efficient when selecting for RL and RDW under water stress conditions. Significant associations between a drought tolerance index and RL, RA and root volume confirmed the importance of these traits in conferring drought tolerance of orchardgrass.  相似文献   
92.
Vinclozolin (VZ) is a pesticide that acts as an anti-androgen to impair reproduction in mammals. However, VZ-induced disruption of reproduction is largely unknown in fish. In the present study, we have established a combination exposure in which adult goldfish were exposed to VZ (30 and 100 μg/L), anti-androgen flutamide (Flu, 300 μg/L), and androgen testosterone (T, 1 μg/L) to better understand effects of VZ on reproductive endocrine system. mRNA levels of kisspeptin (kiss-1 and kiss-2) and its receptor (gpr54), salmon gonadotropin-releasing hormone (gnrh3) and androgen receptor (ar) in the mid-brain, and luteinizing hormone receptor (lhr) in the testis were analyzed and compared with those of control following 10 days of exposure. kiss-1 mRNA level was increased in goldfish exposed to 100 µg/L VZ and to Flu, while kiss-2 mRNA level was increased following exposure to Flu and to combinations of 30 µg/L VZ with Flu, 100 µg/L VZ with T, and Flu with T. gpr54 mRNA level was increased in goldfish exposed to Flu and to combination of 30 µg/L VZ with Flu and 100 µg/L VZ with T. gnrh3 mRNA level was increased in goldfish exposed to 100 µg/L VZ, to Flu, and to combinations of 30 µg/L VZ with Flu, 100 µg/L VZ with T, and Flu with T. The mid-brain ar mRNA level was increased in goldfish exposed to Flu and to combinations of 30 µg/L VZ with Flu, 100 µg/L VZ with T, and Flu with T. Testicular lhr mRNA level was increased in goldfish exposed to Flu and to combination of 30 µg/L VZ with Flu. These results suggest that VZ and Flu are capable of interfering with kisspeptin and GnRH systems to alter pituitary and testicular horonal functions in adult goldfish and the brain ar mediates VZ-induced disruption of androgen production.  相似文献   
93.

In order to study the effects of seed nitrogen content and biofertilizer priming on germination indices of wheat seeds under salinity stress, a factorial experiment based on a completely randomized design with four replications was conducted in 2009. Experimental factors consisted of: (1) the application of different nitrogen fertilizer rates (0, 55, 110 and 165 kg ha?1 N) on parent plants; (2) priming of achieved seeds by biofertilizers (Nitragin, Biophosphorus and distilled water); and (3) different levels of salinity produced by NaCl (0, ?0.4, ?0.8 and ?1.2 MPa). Germination percentage, germination rate, mean germination time, germination index, radicle and plumule length, radicle and plumule dry weight and radicle number per seedling were measured. Nitrogen application increased seed nitrogen content in parent plants. All germination indices decreased with increasing in salinity levels. Biofertilizer priming, especially Nitragin, had a positive effect on germination percentage, radicle number and radicle and plumule length in most salinity levels. The highest values for germination factors were related to achieved seeds from parent plants that were treated with 110 kg ha?1 N. Overall, application of middle levels of N fertilizer (55 and 110 kg ha?1 N) on parent plants combined with seed priming with Nitragin biofertilizer improved the germination indices of wheat under salinity stress.  相似文献   
94.
Nanofibrous mats of poly (?-caprolactone)/nanoclay nanocomposites were fabricated using electrospinning method. Effects of nanoclay content of the nanocomposite on final nanofiber structures were investigated and characterized by scanning electron microscope (SEM) and differential scanning calorimetry (DSC) analysis. The results showed that the presence of the nanoclay promoted the creation of fibrous structure in comparison with solely poly (?-caprolactone). Furthermore, increase in nanoclay content led to the formation of more uniform nanofiber structures and caused a decrease in the mean nanofiber diameter. DSC results showed that the addition of nanoclay reduced the crystallinity of the nanocomposite in compared with pristine PCL. Studies of the mechanical properties, wettability and degradability showed that the presence of nanoclay improved tensile modulus, tensile strength, wettability and biodegradability of the nanocomposites. To evaluate the effect of nanoclay on the cell adhesion and bioactivity of the poly (?-caprolactone)/nanoclay nanocomposites, fibroblasts cells were seeded on the mats. The results showed that the prepared nanocomposite could be a potential candidate for tissue engineering.  相似文献   
95.
In order to identify novel genes encoding enzymes involved in the biosynthesis of nutritionally important omega-3 long chain polyunsaturated fatty acids, a database search was carried out in the genomes of the unicellular photoautotrophic green alga Ostreococcus RCC809 and cold-water diatom Fragilariopsis cylindrus. The search led to the identification of two putative “front-end” desaturases (Δ6 and Δ4) from Ostreococcus RCC809 and one Δ6-elongase from F. cylindrus. Heterologous expression of putative open reading frames (ORFs) in yeast revealed that the encoded enzyme activities efficiently convert their respective substrates: 54.1% conversion of α-linolenic acid for Δ6-desaturase, 15.1% conversion of 22:5n-3 for Δ4-desaturase and 38.1% conversion of γ-linolenic acid for Δ6-elongase. The Δ6-desaturase from Ostreococcus RCC809 displays a very strong substrate preference resulting in the predominant synthesis of stearidonic acid (C18:4Δ6,9,12,15). These data confirm the functional characterization of omega-3 long chain polyunsaturated fatty acid biosynthetic genes from these two species which have until now not been investigated for such activities. The identification of these new genes will also serve to expand the repertoire of activities available for metabolically engineering the omega-3 trait in heterologous hosts as well as providing better insights into the synthesis of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in marine microalgae.  相似文献   
96.
Summary

Disruption of cut flower water relations due to the growth and proliferation of microorganisms in the vase solution is one of the most important factors causing reduced vase-life and deterioration in cut flowers. These experiments were conducted to study the effects of some biocides in controlling microbial proliferation in vase solutions and on water relations in cut Narcissus tazetta L. cv. ‘Shahla-e-Shiraz’, a native bulbous cut flower of Iran. The stems of ‘Shahla-e-Shiraz’ Narcissus cut flowers were exposed to 17 treatments: aluminium sulphate (at 100, 200 or 300 mg l–1), citric acid (at 150, 300 or 450 mg l–1), 8-hydroxyquinoline citrate (at 200, 300 or 400 mg l–1), sodium hypochlorite (at 400, 600 or 800 mg l–1), calcium hypochlorite (at 400, 600 or 800 mg l–1), sterilised distilled water, or tap water (control). Generally, the least effective compounds in controlling microbial proliferation were low concentrations of aluminium sulphate or citric acid. 8-Hydroxyquinoline citrate treatments were most effective, and the vase solution did not contain any microbes until day-6. Vase solution contaminants were yeasts, Bacillus ssp., Staphylococcus ssp., Actinomycetes and Aspergillus ssp. Yeasts and bacilli were the most common microorganisms. Severe symptoms of phytotoxicity such as bud abortion and yellowing in aluminium sulphate-treated flowers, stem proximal-end browning and shrinking in 8-hydroxyquinoline citrate-treated flowers, and bleaching of soaked parts in sodium hypochlorite treatments, were seen. Most solution was taken up in 150 mg l–1 citric acid, while the reduction in fresh weight was least in 200 mg l–1 8-hydroxyquinoline citrate. The correlation between microbial counts and growth rate with solution uptake was slightly negative, but their correlation with fresh weight loss was slightly positive.  相似文献   
97.
Silymarin, an extract from “milk thistle” (Silybum marianum) plant is traditionally used as herbal medicine. The present study was conducted to investigate the clinical effects and possible side effects of silymarin on biochemical blood parameters of rainbow trout (Oncorhynchus mykiss). Fishes were treated with 0 (control), 100, 400, and 800 mg of silymarin per kg of food during 4 weeks. Plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), creatine kinase (CK), glucose, total protein, creatinine, triglyceride, cholesterol, urea, uric acid and liver cellular total antioxidant, and protein content were measured after 7, 14, and 28 days of silymarin treatment. The results showed that oral administration of silymarin in fish significantly reduced plasma glucose and cholesterol levels and relatively increased plasma total protein and globulin concentrations (P < 0.05). Increasing plasma albumin levels indicate the important role of albumin in drug transportation in circulatory system of fish. Silymarin also stabilized cellular membrane structure and regulated the levels of AST, ALT, ALP, CK, and LDH activity. In conclusion, on the basis of these results, oral administration of silymarin up to 400 mg per 1 kg of food has no side effect on blood biochemical and clinical parameters of fishes. However, oral administration of 800 mg/kg- of silymarin caused cytotoxicity and modifications in blood biochemical parameters of fish.  相似文献   
98.
This study was conducted to evaluate the Salvia officinalis hydroalcoholic extract on fertility capacity and behavioral features in rats exposed to immobilization stress. Male rats were randomly divided into five groups; Control; Stressed rats; and Stressed rats received 50, 100 and/or 200 mg/kg bw S. officinalis hydroalcoholic extract. To induce stress, rats were immobilized for 49 days and received S. officinalis extract orally. On day 56, we analyzed behavioral tests and evaluated reproduction capacity by measuring LH, FSH, and testosterone. Sperm parameters such as motility, viability, and total count were also determined. Bodyweight changes were also calculated on day 56. Male rats from different groups were mated with healthy female rats. Data showed that the use of 100 and 200 mg/kg bw S. officinalis extract in stressed rats increased bodyweight gain and improved behavioral disorders compared to control‐matched groups (p < .05). Besides, administration of 100 and 200 mg/kg bw S. officinalis extract had the potential to improve sperm parameters and fertility capacity in stressed rats (p < .05). Decreased testosterone levels were blunted in the stressed rats that received plant extract coincided with the reduction of LH and FSH compared to control‐matched stressed rats (p < .05). We found neutral effects in stressed rats that received 50 mg/kg bw plant extract. Collectively, the hydroalcoholic extract of S. officinalis could improve the fertility capacity and behavioral features under stressful conditions in a dose‐dependent manner.  相似文献   
99.
The purpose of this study was to determine the effects of different concentrations of coenzyme Q10 (CoQ10) and α-tocopherol (T) along with their interaction effects on the quality of preserved stallion semen at 5°C for a period of 48 hours. Semen was collected and diluted with skim milk–based extender that was supplemented with different antioxidants: no antioxidant (negative control [NC]), 0.9% (vol/vol) dimethyl sulfoxide (positive control [PC]), α-tocopherol (5 [T5] or 10 [T10] mM), CoQ10 (1 [C1] or 2 [C2] μM), 1 μM CoQ10 + 5 mM α-tocopherol (C1T5), 1 μM CoQ10 + 10 mM α-tocopherol (C1T10), 2 μM CoQ10 + 5 mM α-tocopherol (C2T5), and 2 μM CoQ10 + 10 mM α-tocopherol (C2T10), then kept at 5°C. The results showed that C1 extender resulted in higher total motility (62.44 ± 3.82) and plasma membrane integrity (65.16 ± 3.63%) compared with NC after 48 hours of storage (P < .05). Different concentrations of α-tocopherol had no significant effects on sperm quality, with the exception of plasma membrane integrity, compared with NC and PC extenders (P > .05). Also, C1T5 extender improved total and progressive motility, plasma membrane integrity and functionality, and decreased lipid peroxidation compared with NC and C2T10 extenders over 48 hours of storage at 5°C (P < .05). The C1T5 extender was similar to C1 and T5 extenders in all semen parameters evaluated during storage time. In conclusion, between previously mentioned extenders, C1T5 could improve stallion sperm quality during 48 hours of storage. In the present study, none of extenders had effect on sperm quality until 24-hour storage.  相似文献   
100.
The objective of the present study was to investigate the morphometrical features of the cat cerebellum using design-based stereology. Cerebellar hemispheres from four male cats were examined. Isotropic, uniform random sections were obtained and processed for light microscopy. Cerebellar total volume (V), white (WM) and grey matter (GM) volume fractions, and the volumes of the molecular and granular layers were measured using the Cavalieri's estimator and the point counting system. Cerebellar surface area was estimated using test lines, and Purkinje cellular and nuclear volumes were analysed using the nucleator technique. The volume of the cat cerebellar hemispheres was 2.06 ± 0.29 cm3. The relative volume fractions of the GM and WM were 70.6 ± 2.6% and 29.3 ± 2.6%, respectively. The surface area of the cerebellar hemisphere was 68.2 ± 17.8 cm2. The volumes of the molecular and granular layers were estimated at 0.89 ± 0.16 cm3 and 0.56 ± 0.1 cm3, respectively. The Purkinje cell volumes were found to be ranging from 1,717 to 28,489 µm3, of which cells with a perikaryon volume of 6,994 µm3 had a higher incidence. The Purkinje nuclear volume was estimated at 440–3,561 µm3, and nuclei with a volume of 1,252 µm3 were the most frequently occurring ones. Our data might contribute to the veterinary comparative neuroanatomy knowledge, help develop experimental studies in this field, and possibly lead to advancement in the diagnosis and treatment of nervous diseases in the cat.  相似文献   
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