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191.
Naseri MK Naseri ZG Mohammadian M Birgani MO 《Pakistan journal of biological sciences: PJBS》2008,11(12):1594-1599
The effect of Mentha longifolia (L.) leaf hydroalcoholic extract (MLE) was examined on rat ileal smooth muscle contractions. Last portion of ileum from male adult Wistar rat was mounted in an organ bath containing Tyrode solution. The tissue was contracted by carbachol (CCh, 10 microM), KCl (60 mM) and BaC12 (4 mM) and then MLE (0.0625-1 mg mL(-1)) was added to the bath cumulatively. The effect of MLE on KCl-induced contraction was examined after tissue incubation with propranolol (1 microM), naloxone (1 microM) and N omega-nitro-L-arginine methyl ester (L-NAME, 100 microM). The effect of MLE on CaCl2-induced ileal contraction in Ca(2+)-free with high potassium Tyrode solution was also evaluated. The role of potassium channels was examined by ileum incubation (5 mim) with tetraethylammonium (TEA, 1 mM). The results showed that KCl-, CCh and BaCl2-induced ileal contractions were inhibited (p < 0.001) by cumulative concentrations of MLE with the same potency. In addition, MLE (0.25-1 mg mL(-1)) inhibited (p < 0.01) ileal contractions induced by CaCl2 (0.45-2.7 mM) in a concentration-related manner. The antispasmodic effect of MLE was affected neither by propranolol, L-NAME nor by naloxone. The MLE concentration-response curve was shifted to the right (p < 0.05) by tissue incubation with TEA. From results it may be suggested that Mentha longifolia hydroalcoholic leaf extract induces its spasmolytic activity mainly through disturbance in calcium mobilization and partly by potassium channels activation. Present results show that Mentha longifolia leaf extract exerts relaxant effects on intestinal smooth muscle, consistent with the traditional use of the plant to treat gastrointestinal disorders such as diarrhea and colic. 相似文献
192.
In this study, the effects of enzymes on wool yarn in the presence of different salts (ammonium sulfate, sodium tetraborate,
and di-sodium hydrogen phosphate) were investigated. Alcalase 2,5 LDX and Savinase 16 LEX were selected as proteolytic enzymes.
In addition, the effects of surfactants (Sandozin NRW, Irgasol NA, Erkantol NR, and Sandozin EH) on the enzyme treatment of
wool yarn were evaluated. The results indicated that the effects of enzymes on wool yarn were greatest in the presence of
sodium tetraborate. Furthermore, the properties of wool yarn such as weight loss, strength loss, and hairiness were influenced
by these surfactants. The SEM images of the treated samples confirmed the obtained results. 相似文献
193.
Maryam Azadbar Akram Ranjbar Azadeh Hosseini-Tabatabaei Abolfazl Golestani Maryam Baeeri Mohammad Sharifzadeh Mohammad Abdollahi 《Pesticide biochemistry and physiology》2009,95(3):121-125
The main objective of this study was to investigate the possible protective effect of pentoxifylline as a phosphodiesterase 5 inhibitor used as a cardiovascular medication on malathion-induced changes on rat mitochondrial-bound hexokinase activity.Animals in four various groups received moderate toxic dose of malathion (200 mg/kg/day), effective dose of pentoxifylline (50 mg/kg/day) alone and in combination, and the control group that received only vehicle. All administrations were done intraperitoneally for one week. At the end of the experiment, the brain was removed and the mitochondria were isolated. Hexokinase (HK) activity, cellular lipid peroxidation (LPO) and total antioxidant capacity (TAC) were analyzed in brain mitochondria.Malathion noticeably decreased TAC and increased HK activity and LPO in the mitochondria whereas pentoxifylline significantly restored malathion-induced changes in LPO, HK, and TAC.The results of the present study indicate that phosphodiesterase 5 inhibition remarkably protects brain mitochondria from malathion-induced changes on HK activity and oxidative stress. 相似文献
194.
Maryam Shekari Kayvan Etebari Abdolahad Shadparvar 《Pesticide biochemistry and physiology》2008,91(1):66-74
Methanolic extract of Artemisia annua L., a weed collected around paddy fields in north of Iran, was investigated for its toxic effects on: feeding, growth, fecundity, fertility including the biochemical characteristics of elm leaf beetle Xanthogaleruca luteola Mull. The toxicity tests indicate that insecticidal effect was 2.4-fold higher in 3rd instar larvae than in adults. The LC50 was 48% and 43.77% of a methanolic leaf extract at 24 and 48 h, respectively. The feeding deterrence was highest at 10% concentration and lowest at 0.625% for 3rd instar larvae and adults during the first 24 h and decreased thereafter. Larval duration significantly increased at higher concentrations. Larval treatment with 10% methanolic extract resulted in deformed adults (adultoids) with drastic changes in gross morphology of female reproductive system. Food digestion and assimilation significantly decreased in adults. Larval duration and adult fecundity and fertility were also significantly reduced. Twenty-four hours after treating 3rd instar larva with the extract the levels of glucose, protein, urea, uric acid, α-amylase, alkaline phosphatase, alanine amino transferase and aspartate amino transferase significantly changed. However, at 48 h the extract lost its potency. The extract did not effect the level of cholesterol in treated larva. These results indicate that Artemisia annua L. extract contains inhibitors of key metabolic pathways that may be useful in future control of the elm leaf beetle. 相似文献
195.
Amongst all forest utilization phases, harvesting plays a key role as the beginning phase of the utilization cycle and has a significant effect on the following phases.In this research, in order to examine the reduction of costs with respect to present and planned operations, the starting time of the harvesting or cutting phase and work flow were recorded. The starting time of each phase of the entire operation was recorded as well. Before harvesting the marked tree, the appropriate felling direction was determined and the azimuth of the correct direction was taken.The results indicate that there was not a meaningful relationship between the differences in direction of a leaning tree compared with the felling direction. However, there was a significant relationship between the difference of the defined and felling direction and the difference in tree leaning and defined direction. The same trend was observed between tree leaning and felling directions and tree leaning and defined directions. On the other hand,there was no significant relationship between tree leaning and felling directions and the defined and tree felling directions. In addition, this research shows that with an increase in tree volume, the time for tree cutting rose.Furthermore, when the difference of tree leaning and felling direction decreased, the time to cut the tree declined.The regression equation is Y = 168.9–0.14(the difference between tree leaning and felling direction) + 0.7(volume). 相似文献
196.
The aim of the present study was to compare the effects of drought on some physiological and biochemical parameters and to assess the inducing effects of Penconazole (PEN) on drought tolerance in two cultivars (RGS003 as a drought tolerant and Sarigol as a drought sensitive) of canola. Plants were treated with various PEG concentrations (0, 5, 10, and 15%) without or with PEN (15 mg l?1). Decrease in fresh weight (FW) and dry weight (DW) in Sarigol under drought was higher than that of RGS003. Surprisingly, PEN reversed prominently the negative effects of drought on FW and DW in RGS003. Concomitantly, PEN treatment decreased malondialdehyde content in RGS003 under drought. Moreover, higher content of proline in RGS003 under all drought levels could be considered as a factor for drought tolerance of this cultivar. Superoxide dismutase (SOD), catalase (CAT) and Polyphenol oxidase (PPO) activities were induced by PEN in both cultivars under drought. Inducing effects of PEN on phenylalanine ammonia lyase and thyrosine ammonia lyase activities decreased by increasing of drought levels in both cultivars. In summary, PEN alleviated the negative effects of drought in RGS003 cultivar by inducing activities of SOD, CAT and PPO and proline content comparing to Sarigol. 相似文献
197.
A study was conducted to evaluate the effect s of silver nanoparticles for ameliorating negative effects of salinity on germination and growth of Fenugreek seeds. In order to investigate salinity stress on Fenugreek germination indices, an experiment was carried out in Iran from October 2014 to November 2014 at Ferdowsi University of Mashhad, in the biotechnology Laboratory, to create salinity stress, sodium chloride (NaCl) at the levels of 0 (as control), 5, 10, 15 and 20 dS/m and Five levels of silver nanoparticles (0, 10, 20, 30 and 40 μg mL–1) on Fenugreek seed (Trigonella foenum-graecum); were tested Germination characteristics such as total germination (GT), Germination Speed Index (GSI), Shoot and Root of seedling long, Fresh Mass and Dry Mass were measured. Results showed the great effects of silver nanoparticles to improve salinity stress on Fenugreek seed germination. Results showed a significant reduction in germination percent and seedling growth due to the salinity stress while significantly increased with silicon nano-particles application. In without silver nanoparticle low level of salinity (0 dS/m) increased seed germination percentage, while the high levels (5, 10, 15 and 20 dS/m) inhibited the seed germination significantly. The results showed that the effect of AgNPs was significant on germination percentage in P ≤ 0.05. Overall, application of AgNPs was beneficial in improving salinity tolerance in the Fenugreek seedling and its application may stimulate the differences defense mechanisms of plants against salt toxicity. 相似文献
198.
In sustainable agriculture, the protection of environment against pollution is the main goal for consumers. Nowadays, the overuse of pesticides and chemical fertilizers, are one of the main causes of environmental pollution. It is claimed that incorporation of organic compound into soil enhances nutrient availability and plant productivity. A greenhouse experiment was conducted to determine the effects of 0%, 1.5% and 3% cattle manure biochar and 0, 300 and 600 mg K-nano chelate kg?1 soil on agronomic properties and nutrient status of Ocimum basilicum L. Biochar increased leaf area and plant height, significantly. Application of 1.5% and 3% biochar increased fresh weight by 40% and 42% and dry weight by 50% and 49%, respectively. Addition of 3% biochar increased P, K and Mn concentrations by 45%, 17% and 109%, respectively. Biochar increased N, P, K, Zn and Mn uptake, significantly. Addition of 300 mg K increased dry weight by 15%; while application of 600 mg K decreased it. Application of 300 and 600 mg K-nano chelate increased K and Zn concentration and K uptake significantly. Furthermore, 300 mg K increased Cu and Zn uptake. In order to achieve sustainable agricultural productions, biochar application is recommended especially in the soils of arid and semiarid regions. 相似文献
199.
Reproductive performance of Holstein dairy cows in Iran 总被引:2,自引:2,他引:0
Maryam Ansari-Lari Mojtaba Kafi Mohammad Sokhtanlo Hasan Nategh Ahmadi 《Tropical animal health and production》2010,42(6):1277-1283
The objectives of the present study were to describe the current reproductive parameters of Holstein dairy cows in Iran and
to determine factors which have a significant effect on reproductive performance with emphasis on high-producing dairy cows.
Five large Holstein dairy herds from the major milk production areas of Iran were selected for this study. Reproduction data
including parity of dam, calving date, days to first service, days open, number of services, dry period, and occurrence of
diseases for cows that calved from 2004 to 2007 were collected from the herds' databases. To determine the effects of year
and season of calving, disease status, level of milk production, and parity of dam on reproductive parameters, the proc-mixed
procedure in SAS software was used. Overall, data about 8,204 lactation were collected for the study. Results showed that
mean (±SD) days open, calving interval, and days to first service for study herds were 134 (±89), 403 (±86), and 67 (±38)
days, respectively. Conception rates at the first service and the overall service-conception rate were 41.6% and 41%, respectively.
The level of milk production and diseases had significant negative effects on days open and service per conception (P < 0.05); statistical analysis showed that for every 100-kg increase in milk yield, days open will increase by about 0.3 days.
However, no significant effect of level of productivity was observed on days to first service. The results of this study indicate
that high milk production is a risk factor for decreasing fertility in Iran, like many other parts of the world. 相似文献
200.
Maryam Muhammad Lawal U. Muhammad Abdul-Ganiyu Ambali Aliyu U. Mani Samuel Azard Lisa Barco 《Veterinary microbiology》2010,140(1-2):131-135
The prevalence of Salmonella associated mortality at hatching was investigated in three hatcheries in Jos, central Nigeria. Their susceptibility to antimicrobial agents was also evaluated. S. Kentucky and S. Hadar were isolated. While half of the isolates were from internal organs, 26.7% came from meconial swabs of dead-in-shell embryos, 17.8% from intestinal samples and 4.4% from egg shells. S. Hadar is known to colonise only the gut and is classified as non-invasive, but in this study 82% were obtained from internal organs which suggests that infections with this serotype may also cause invasive disease. Antimicrobial susceptibility tests showed a high prevalence of antimicrobial resistance in the study area with complete resistance to gentamycin, enrofloxacin, nalidixic acid, tetracycline and streptomycin and substantial resistance to triple sulphur and ciprofloxacin. Six multiple resistance profiles were recorded with a high level of multiple resistance to quinolones. Quinolone resistance has implications for veterinary and human therapy as their misuse in poultry could lead to the emergence of resistant animal and zoonotic pathogens. 相似文献