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91.
This research was carried out to determine the effects of rate and time of nitrogen (N) application on safflower in a calcareous soil. The nitrogen rates were 50, 75, 100, 125, and 150 kg ha?1 and three split application methods were used. Experimental treatments were conducted as a factorial in a randomized complete block design (RCBD) with three replications. Duncan's Multiple Range Test (DMRT) indicated that the three split application of 100 kg ha?1 of nitrogen in stages of sowing date, early stem elongation, and early flowering had higher grain yield (2627 kg ha?1) than other treatments. This result was forecasted by results of increases in number of heads per square meter (heads m?2), number of grains per head (grains/head), and thousand grain weight (TGW). The highest oil yield was 755 kg ha?1 with the 100 kg ha?1 nitrogen application and was 727 kg ha?1 in treatment of three split application.  相似文献   
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93.
Waste cotton fibers were used to produce activated carbon fiber (ACF) via chemical activation method with phosphoric acid. The effect of different operational parameters on the adsorption capacity and yield of activated carbon fibers was studied by Taguchi experimental design. Optimized conditions were: Activation temperature of 450 °C, activation time of 0.5 h, impregnation ratio of 2, and the rate of temperature rising of 10 °C min?1. The activated carbon fiber produced under optimized conditions was characterized by pore structure analysis, scanning electron microscopy (SEM), X-ray energy-dispersion spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction analysis (XRD). The obtained results showed that the produced activated carbon has developed porous structure, fibrous shape, predominantly amorphous structure, large number of oxygen functional groups, and acidic nature.  相似文献   
94.
This study was conducted to determine effects of intravenous detomidine on intraocular pressure (IOP) readings obtained by applanation tonometry in clinically normal horses. Twenty horses were randomly divided into two groups of 10 each (treatment and control). All horses in the treatment group received intravenous detomidine alone (20 μg/kg). The horses in the control group received only intravenous saline (0.2 mL/100 kg). The IOP values were measured before the treatment (T0) and then at 5 (T5), 20 (T20), 60 (T60), and 120 (T120) minutes after drug administration in both groups. A significant decrease in IOP values was observed in both right and left eyes of the horses in the treatment group at T5, T20, and T60 in comparison with the baseline values (P < .001). The observed decrease was only statistically significant in the right eyes of the treatment group horses at T120 (P = .044). Mean IOP was not significantly altered at any time point during the treatment period compared with the baseline evaluations in both eyes of the horses in the control group. This study demonstrates that the use of intravenous detomidine lowers IOP quickly.  相似文献   
95.
Successful identification of homozygous and heterozygous transgenic plant with currently available techniques such as southern blot hybridization, dot blot hybridization, fluorescence in situ hybridization (FISH) and so on, demands tedious and time-consuming procedures with a high proportion of ambiguous results. Real-time PCR is a quantitative and extremely precise method with high throughput that could be applied to the analysis of large number of plants differing only by a factor of two in the amount of target sequences. In the present study, we determined zygosity level of transgenes in cotton [Gossypium hirsutum L.] with two zygosity assays, based on TaqMan technology that uses a fluorogenic probe which hybridizes to a PCR target sequence flanked by primers. TPS, a single copy gene per haploid Gossypium hirsutum genome was used as the endogenous reference to estimate copy number of transgene. Both assays were accurate and reproducible in determination of the number of transgenes present in a cell line. These methods are standard curves and Delta delta C t method.  相似文献   
96.
In this study, juvenile beluga (Huso huso) were fed diets containing different carbohydrate to lipid ratios for 5 months. At the end of the culture period, proximate compositions of the fish carcasses (moisture, protein, fat, and ash) were measured. Then, qualitative changes in the fishes were evaluated during 24-days refrigeration (4°C), along with changes in their total volatile bases nitrogen (TVN), thiobarbituric acid (TBA), free fatty acids (FFA), pH, and muscle texture profile analysis. The results of proximate analysis of the carcasses showed that moisture, protein, and ash of the carcasses increased significantly (p < 0.05) with higher carbohydrate to lipid ratio, but fat content of the carcasses decreased significantly (p < 0.05). Further, during refrigeration, TVN, TBA, and FFA increased significantly in all the samples (p < 0.05), but these changes did not follow the same pattern in all the treatments. Tissue hardness decreased during preservation. Although pH changes in the fillets were low, they were significant and without a clear-cut pattern. The results showed that use of different carbohydrate to lipid ratios in diet does not lead to clear-cut changes in qualitative characteristics of beluga fillets during refrigeration.  相似文献   
97.
Background: To achieve multiple oocytes for in vitro fertilization, ovulation induction is induced by gonadotropins; however, it has several effects on oocytes and embryo quality and endometrium receptivity. The aim of this study was to assess ultrastructural changes of corpus luteum after ovarian induction using human menopausal gonadotropin (HMG) and human chorionic gonadotropin (HCG) during luteal phase at implantation period. Methods: Female NMRI mice (6-8 weeks) were divided into control and stimulated groups. In the control group, the mice were rendered pseudopregnant and in the ovarian induction group, the mice were rendered pseudopregnant after the ovarian induction. The samples were obtained from the ovary in each group at the same time during luteal phase at implantation period. Ultrastructural changes were assessed using electron microscopy study. Results: Our results displayed some identifiable changes in ultrastructure of corpus luteum in ovarian induction group. These changes included enhancement of the apoptosis and intercellular space, whereas the angiogenesis was decreased. The findings indicated a decline in organelle density in the cytoplasm of ovarian induction, such as mitochondria, endoplasmic reticulum and polyribosome. Furthermore, chromatin condensation of nuclei was observed in some cells. Conclusion: The ovarian induction using HMG and HCG resulted in some ultrastructural changes on the corpus luteum at implantation period, which could affect on the pregnancy rate.Key Words: Corpus luteum, Luteal phase, Ultrastructure, Ovarian induction  相似文献   
98.
The potential of hyperspectral imaging (HSI) in the visible-near infrared (445-945 nm) wavelength range to discriminate between casing soil, enzymatic browning and undamaged tissue on mushroom (Agaricus bisporus) surfaces was investigated. A calibration set of 108 damage free mushrooms, grown under controlled conditions in a research station, were first tested as undamaged class (U) and then were divided into 2 groups of 54 samples. The first group was smeared with casing soil and designated as casing soil class (C) and the second group was subjected to vibrational damage resulting in enzymatic browning and designated as damaged class (D). Partial least squares discriminant analysis (PLS-DA) models were developed to classify mushroom tissue as one of the three classes investigated (U, C and D) using pixel spectra from each class. Prediction maps were obtained by applying the developed models to the hyperspectral images of candidate mushrooms. Percentages of pixels classified into each class were also calculated for the mushrooms studied in the calibration set. Results obtained showed that the developed models performed satisfactorily to discriminate between the 3 classes studied. Comparison of red-green-blue (RGB) and hyperspectral image analysis showed that HSI was better able to identify the regions containing casing soil. Model validation was performed using 3 different test sets of mushrooms obtained from a commercial producer. It was found that the developed PLS-DA models were satisfactorily capable of identifying undamaged regions, casing soil and enzymatic damaged areas on mushrooms from the validation sets.  相似文献   
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100.
Objective To determine reference values for Schirmer tear tests I and II in clinically normal pigs. Animal studied Twenty clinically normal Landrace pigs (10 males and females) without ocular abnormalities were used in this study. Procedures In all pigs, Schirmer tear tests (STT) I and II were performed by using a sterile Schirmer tear test standardized strip (Schirmer‐Tränentest®, Germany) placed in the lower conjunctival fornix for 1 min. Results For each test (STT I and STT II), no differences were observed between the right and left eyes (P ≥ 0.5). The mean ± SD STT I value was 15.6 ± 3.7 mm/min (range, 10–22 mm/min), while the mean STT II value was 12.4 ± 3.8 mm/minute (range, 5–18 mm/min). The mean STT II value was significantly lower than the STT I level (P < 0.001). Animal gender did not have a significant effect on STT I and II values (P = 0.52). The mean ± SD STT I/II values of 10 juvenile pigs were significantly lower than the mean ± SD STT I/II values of 10 adult pigs (P < 0.001). Conclusions This study of 20 Landrace pigs provided valuable information on normal STT I/II in this species. Knowledge of normal STT reference values in pigs enables the clinician to evaluate corneal pathology and diagnose tear deficiency syndromes with greater accuracy.  相似文献   
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