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211.
This study was designed to assess the effect of hyperlipidemia on cardiovascular responses to adrenergic stimulation in a porcine model. Four-week-old piglets (n = 10) were divided into two groups; one fed a control diet and the other was fed an atherogenic diet for 8 weeks. Cardiovascular responses were evaluated to both norepinephrine (NE; 0.5 and 2.5 micrograms/kg) and isoproterenol (ISO; 0.1 and 0.5 microgram/kg) from simultaneous recordings of femoral arterial pressure, heart rate, left intraventricular pressure and left intraventricular dP/dt. It was found that no significant difference in the baseline values of cardiovascular function was observed between the control and hyperlipidemic groups. However, in the hyperlipidemic group as compared with the control group: 1) arterial blood pressure responses to NE were significantly increased (P less than 0.05), 2) cardiac contractile responses to NE and ISO were significantly potentiated (P less than 0.05), and 3) reflex bradycardia in response to increasing arterial blood pressure did not occur. These findings indicate that hyperlipidemia can potentiate the cardiovascular responses to adrenergic stimulation, whereas reflex cardiovascular regulation is somewhat altered by hyperlipidemia. Conceivably, these observations may have relevance to the possible role of the mechanism of the interaction of hyperlipidemia and hypertension in atherogenesis.  相似文献   
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The incidence of bovine mastitis and the bulk milk somatic cell count (BMSCC) are influenced by season, which may be associated with innate immune functions, including antimicrobial components in mammary glands. Therefore, the present study was conducted to examine the effect of season on antimicrobial components in milk. Rectal temperature and plasma cortisol, thyroxine, and derivatives of reactive oxygen metabolites (d‐ROMs) were measured as stress parameters. Concentrations of lactoferrin (LF), lingual antimicrobial peptide (LAP), psoriasin (S100A7), and Immunoglobulin A (IgA) in milk were measured as indicators of innate immune function. LF and LAP concentrations were significantly lower in summer than in winter and spring, respectively, whereas the concentration of S100A7 was significantly lower in winter than in spring and autumn. The rectal temperature was significantly higher in summer than in other seasons, whereas plasma cortisol, thyroxine, and d‐ROMs did not exhibit any seasonal variation. In conclusion, even though stress parameters were not changed, the concentration of antimicrobial components, such as LF and LAP, decreased in summer, which may explain the frequent occurrence of mastitis during this season.  相似文献   
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Objective: To describe surgical repair of a complete endocardial cushion defect (ECD) in a dog. Study Design: Clinical report. Animal: A 5‐month‐old, 9.2 kg male Shetland sheepdog. Methods: Echocardiographic examination revealed an ostium primum atrial septal defect (ASD), an inlet ventricular septal defect (VSD), mitral regurgitation (MR) and tricuspid regurgitation (TR), and a complete ECD was diagnosed. Surgical correction was performed using cardiopulmonary bypass (CPB) via right atriotomy. A polytetrafluoroethylene (PTFE) patch was secured along the margin of the inlet VSD using simple continuous suture, then the cleft in the septal mitral leaflet was sutured. Similarly, the cleft in the septal tricuspid leaflets was sutured. To complete inlet VSD closure, the VSD patch was secured to these sutured leaflets by simple continuous suture. Another PTFE patch was used to close the ostium primum ASD. Result: After surgery, MR, TR, and interventricular shunting were decreased. The dog was alive 6 years and 5 months after the surgery with no evidence of an interventricular shunt, TR, or other clinical signs. Conclusions: Complete ECD in a dog was corrected using a 2‐patch technique under CPB.  相似文献   
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Asparagus (Asparagus officinalis L.) is a dioecious plant. In general, male and female plants are used for open-field culture and intensive cultivation, respectively. Farmers distinguish between the sexes by observing the form of the flower organs. However, because flowering begins 2?C3 years after planting, the sexes cannot be differentiated at transplantation by using this method, and planting of an all-male population is not possible. In this study, the usefulness of loop-mediated isothermal amplification (LAMP), a simple method of gene amplification, for sex distinction at the DNA level was determined. In addition, the phenotypic differences in seeds and seedlings of male and female plants were investigated for application as a method of early sex distinction. By using the LAMP method, the sex could be correctly identified in 100% of the seedlings, suggesting that this method is effective for sex distinction at the gene level. Principal component analysis was conducted with 11 selected parameters after investigating the seeds and seedlings of both male and female plants. The results revealed that male plants tend to have many stalks or cladophylls and female plants tend to have large plant forms, suggesting that the sexes can be distinguished by the external appearance of the seedlings before planting. LAMP and observation of the seedling phenotypes could be useful methods of sex distinction for increasing the efficiency of asparagus breeding.  相似文献   
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Interspecific hybridization is a useful technique to introduce characteristics from wild species into crops. Garden asparagus (Asparagus officinalis, 2n = 2x = 20) is an economically important vegetable that is native to the Mediterranean region but widely cultivated in many countries. The genus Asparagus is comprised of over 100 species. Asparagus kiusianus (2n = 2x = 20) is a wild asparagus species endemic to Japan. This species occurs on the coast and is likely to be a salt-resistant species. Although the geographic distribution of these two species is not close, molecular phylogenetic analysis demonstrated that these two species are closely related. In this study, a reciprocal cross between A. officinalis and A. kiusianus was carried out by hand pollination, and progeny were obtained from both crossings. These progeny exhibited a morphologically intermediate phenotype in terms of flower shape, and restriction fragment length polymorphism analysis confirmed that these were indeed interspecific hybrids. The interspecific hybrids were fertile, and backcross progeny with garden asparagus was also generated. These interspecific hybrids are expected to supply novel traits to garden asparagus.  相似文献   
218.
Polyphenolic compounds from chestnut astringent skin (CAS) were purified by dialysis, using Diaion HP-20 and Sephadex LH-20 columns. During purification, specific α-amylase inhibitory activities were increased about 3.4-fold, and the 50% inhibition value was 5.71 μg/mL in the Sephadex LH-20 fraction (SE-fraction). The SE-fraction contained about 67% of the total polyphenols, 57.3% of the flavanol-type tannins, and 51.3% of the procyanidins. Strong antioxidant activity was observed in the SE-fraction. Oral administration of the SE-fraction in rats fed corn starch significantly suppressed an increase in blood glucose levels. The SE-fraction contained gallic acid and ellagic acid. The MALDI-TOF spectrum showed a peak series exhibiting a mass increment of 288 Da, reflecting the variation in the number of catechin/epicatechin units. Our results suggest CAS contains polyphenols with strong α-amylase inhibitory activity. The data also suggest CAS polyphenols might be oligomeric proanthocyanidins with gallic acid and ellagic acid.  相似文献   
219.
Although it has been reported that dietary lycopene, the main carotenoid in tomato, improved drug-induced nephropathy, there are no reports on the effect of orally administered lycopene on the in vivo renal reducing (i.e., antioxidant) ability. The radiofrequency electron paramagnetic resonance (EPR) method is a unique technique by which the in vivo reducing ability of an experimental animal can be studied. In this study, the in vivo changes in the renal reducing ability of rats orally administered lycopene were investigated using a 700 MHz EPR spectrometer equipped with a surface-coil-type resonator. Rats were fed either a control diet or a diet containing lycopene. After 2 weeks, in vivo EPR measurements were conducted. The renal reducing ability of lycopene-treated rats was significantly greater than that of the control. This is the first verification of in vivo antioxidant enhancement via dietary lycopene administration.  相似文献   
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