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51.
The computer‐assisted sperm analysis (CASA) has become a standard laboratory tool. Although it contributes a lot to the objective sperm motility assessment, its measurements may be affected by many factors. The aim of the study was to evaluate the effect of chamber on boar semen CASA results. Totally, 100 extended (30 × 106 sperm/ml) boar semen samples were analysed by CASA. Each sample was evaluated using Makler, Leja 4 chamber 20 μm and conventional glass slide/coverslip chambers (MC, LC and GSC, respectively). The differences in values between MC and LC and between MC and GSC were significantly positive (higher values for MC compared with LC and GSC) for total motility, progressive, rapid movement, VCL, VSL, VAP, STR and hyperactive, thus indicating a systematic effect. Between LC and GSC, the differences in many parameters (non‐progressive, progressive, slow, LIN, STR, hyperactive) were evenly distributed around zero, while in all other parameters the differences were significantly positive (higher values for LC compared with GSC), except for medium movement. Based on the estimated intraclass correlation coefficients, the method agreement between MC and LC and between LC and GSC was overall moderate to good, depending on the parameter; nonetheless, it was poor between MC and GSC. The limits of agreement between methods can vary considerably depending on the parameter and should be considered when comparisons between CASA measurements of different andrology laboratories or studies have to be performed.  相似文献   
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53.
Background: Regenerative medicine has become one of the most promising therapies of equine osteoarthritis. Platelet lysate (PL) is rich in bioactive proteins and growth factors that play a crucial role in tissue healing.

Objective: To evaluate the efficacy of intra-articularly injected autologous PL in equine athletes with naturally occurring osteoarthritis.

Animals and methods: Fifteen warmblood geldings aged 8–19 years with osteoarthritis of the distal interphalangeal joint were included in this study. They were randomly divided into two groups; 10 horses received intra-articular injections of PL and 5 of normal saline (controls). Before treatment, platelet-derived growth factor (PDGF) levels in basal plasma and prepared PL were estimated. Each joint was injected twice within a three-week period. Lameness was evaluated using the American Association of Equine Practitioners grading system, before treatment and 10 days after each intra-articular injection. Horses were examined fortnightly for one year. Radiographic examination was performed six months post-treatment. The generalized estimating equation test was used for statistical analysis.

Results: Acceptable levels of PDGF were detected in PLs (mean ± SD: 258.0 ± 52.3 pg/ml). The majority of horses (9/10) responded positively to PL treatment presenting lower lameness grades (p < 0.0005) compared to controls 10 days after the second injection, and returned to normal athletic activity. Radiographs revealed no changes in osteoarthritis lesions six months after treatment. One year post-injections, however, all horses relapsed to their initial degree of lameness.

Conclusion: Intra-articularly injected autologous PL is an efficient method for temporarily managing osteoarthritis of the distal interphalangeal joint in athletic horses.  相似文献   

54.
Root active uptake and remobilization of boron (B) have been accepted as mechanisms contributing to nutrient efficiency under low supply of boron. Here, we examined the existence of these mechanisms in eggplant (Solanum melongena L.) supplied either with luxury (100 μM, B+) or low (7.5 μM, B–) B in the growth medium via semihydroponic cultivation. Boron treatment was marginally not limiting growth thus avoiding side‐effects and impairment of acclimation mechanisms of plants. The induction of a B‐concentrating mechanism was evident in the roots as B concentration in the xylem sap was only decreased by 23% in B– compared to B+ plants, i.e., B– roots concentrated B by a factor of 2.7 relative to the external solution. Leaf B concentration in the B– treatment decreased by 33% and 40% in young fully expanded and mature leaves, respectively. Larger differences were observed in the soluble B fraction that decreased by 65% in mature leaves. However, both total and soluble B concentrations in developing leaves were almost equal for both treatments exhibiting a pattern commonly observed in B‐remobilizing plants. On the other hand, amounts of B export in the phloem sap were small compared to other species in which B is highly mobile. The B export rate from source leaves was slightly increased under low B supply while that of sucrose was not affected. We conclude that the root concentrating mechanism contributes to the alleviation of B deficiency in eggplant under low B supply while B remobilization may also contribute to a lower degree.  相似文献   
55.
A total of 65 surface (0–20 cm) soil samples were collected in an effort to estimate the arsenic background values in Kavala area, Northern Greece. Arsenic was extracted by HNO3 from the <200?µm grain size fraction, and its concentrations were determined in all samples by inductively coupled plasma–mass spectrometry. Arsenic concentrations were log-transformed, and log-normal probability plots (Q–Q plots) were generated. The geochemical background was calculated as the values that lie between g/d and g?×?d (g, geometric mean; d, geometric standard deviation), which are 3.5 and 25.8 mg kg?1, respectively. The baseline value (g) was 9.5 mg kg?1. With the aid of GIS software, arsenic geochemical maps of the study area were created. The majority of the arsenic elevated concentrations were found in the proximity of the industrialized zone of Kavala.  相似文献   
56.
A method based on high-performance liquid chromatography with diode-array detection was developed and validated aiming at the simultaneous determination of terbuthylazine (TER) and its five major metabolites, desisopropyl-hydroxy-atrazine, desethyl-hydroxy-terbuthylazine, desisopropyl-atrazine, hydroxy-terbuthylazine, and desethyl-terbuthylazine. Although s-triazines are used worldwide as herbicides for agricultural and nonagricultural purposes, there is limited information on the environmental impact of TER degradation products. The proposed method includes a solid-phase extraction procedure (using MCX cartridges) with adequate recovery efficiency (70-80%). The statistical evaluation of the method reveals good linearity, accuracy, and precision for the compounds determined, with RSD values less than 14.6%, while the detection limit was found to be 0.05 microg L(-1) for DIHA and 0.01 microg L(-1) for the other substances. This method can be employed in biodegradation studies of TER and its metabolites in water samples from constructed wetlands, thus assisting the evaluation of their environmental impact.  相似文献   
57.
The relationship between acrylamide and its precursors, namely, free asparagine and reducing sugars, was studied in cakes made from potato flake, wholemeal wheat, and wholemeal rye, cooked at 180 degrees C, from 5 to 60 min. Between 5 and 20 min, major losses of asparagine, water, and total reducing sugars were accompanied by large increases in acrylamide, which maximized in all three products between 25 and 30 min, followed by a slow linear reduction. Acrylamide formation did not occur to a large degree until the moisture contents of the cakes fell below 5%. Linear relationships were observed for acrylamide formation with the residual levels of asparagine and reducing sugars for all three food materials.  相似文献   
58.
This article deals with the impacts of past mining activities andinefficient water resources management on groundwater quality inthe Lavrio area. Thirty-three water samples were collectedduring March 1998 and were analyzed for major ions (Ca, Mg, Na,K, HCO3, Cl, NO3, SO4, PO4), trace elements(Fe, Pb, Ni, Zn, Mn, Cu, Cr, Cd) and water parameters (Temperature,pH, conductivity, hardness and SiO2). High concentrationsof heavy metals (lead, cadmium, zinc, nickel) are recorded ingroundwater samples in the Lavrio area. The highestconcentrations are recorded in the unconfined aquifer (alluvialdeposits and schists), due to mining activities. Qualitydeterioration of groundwater is also decumented and attributedto seawater intrusion and nitrate pollution of agriculturalorigin. The data were subjected to simple correlation analysisand R-mode factor analysis in order to examine the relationshipsbetween the parameters. There is a relationship between theelements participating in the sulfide (Pb, Zn, Cu, Cd) andiron-manganese mineralization and a strong relationship betweenNi–Cr. In the factor analysis a four-factor model is suggested,which can explain 72.5% of the total variance. The contributionof each factor at every site is also computed and maps showingthe geographical distribution are illustrated. The areas withhigh concentrations of heavy metals are defined from these maps.  相似文献   
59.
Possible associations between certain physical properties of cervical mucus (CM) and ovulation rate were studied in 21 superovulated Holstein cows. In CM samples collected at the beginning of estrus (0 h) and in 4 h intervals for the following 24 h, the pH, the spinnbarkeit (spinability), and the crystallization value were measured. Blood samples, collected at the same time points with CM samples, were assessed for progesterone and estradiol concentrations. At 48 h the number of ovulated follicles was counted by transrectal ultrasonography and the animals were allotted into 2 groups according to the occurrence of at least one (group A, n = 16) or no (group B, n = 5) ovulations. The pH was lower (P < 0.05) at 8 h (7.00 + 0.24) in group A compared with group B (7.55 + 0.12). In group A, spinnbarkeit was significantly lower at 0 h and 20 h, and higher at 8 h and 16 h compared with group B (0 h: 2.50 + 0.82 versus 6.95 + 0.41; 20 h: 3.00 + 1.89 versus 5.38 + 0.94; 8 h: 7.00 + 0.87 versus 2.75 + 0.43; 16 h: 7.00 + 1.41 versus 4.30 + 0.71, for groups A versus B, respectively). Crystallization was significantly lower at 4 h (2.00 + 0.63) and 20 h (1.50 + 0.82) in group A compared with group B (3.13 + 0.32 at 4 h and 3.00 + 0.41 at 20 h). Progesterone at all time points, and estradiol at 16 h, 20 h, and 24 h were lower (P < 0.05) in group A than in group B. The pH, crystallization, estradiol, and progesterone differed (P < 0.05) within one group, while sbk differed within both groups.Our results imply that during the periovulatory period, steadily low progesterone concentrations trigger alterations of certain CM characteristics, while extremely high estradiol concentration could prevent the occurrence of these alterations.  相似文献   
60.
Background: In farm animal practice, determination of blood glucose concentration under field conditions is often necessary. Objective: As there is no portable glucose meter device developed for use in farm animals, the analytical accuracy of a portable glucometer designed for people was evaluated for its use in cattle and sheep. Methods: Blood samples from 90 cattle and 101 sheep were used in the study. Glucose concentration was determined in whole blood immediately after blood collection from the jugular vein with the One Touch Vita portable glucometer and in serum with an enzymatic colorimetric method. The agreement between methods was assessed by Passing and Bablok regression analysis. The precision and the accuracy of the measurements were determined using the concordance correlation coefficient. Results: There was a strong linear relationship between the glucose values obtained using the portable glucometer and those obtained by the bench method in both cattle and sheep. Precision was 95% for cattle and 88% for sheep, whereas accuracy was 92% and 99%, respectively. The mean glucose values obtained using the portable glucometer were significantly lower by 8.3% in cattle and 3.2% in sheep than those determined by the bench method. Conclusion: The One Touch Vita portable glucometer can be used in clinical practice to determine blood glucose concentrations in cattle and sheep, but reference intervals (RI) must be corrected to allow for negative bias. Based on these equations the RI for blood glucose in cattle and sheep using the portable glucometer were corrected to 1.84–4.17 and 2.41–4.35 mmol/L, respectively.  相似文献   
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