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The static properties of the confined in the nanometer cylinder tubes are investigated by molecular dynamics simulation. The modified Lennard Jones potential function is adopted to describe the interaction between fluid fluid and fluid solid. In which, the introduced parameter α can be adjusted to change the wetting intensity between the fluids and solid solid wall. Furthermore, the microscopic properties of the fluids in the nanometer tube are characterized by the density distribution, the pair distribution function and the axial velocity distribution. The results show that the interaction strength of the atoms between the fluids and solid wall has a significant influence on the microscopic properties of the fluids as well changes the microscopic state in the different radial region and the motional properties of the atoms consisted of the fluids in the tube. 相似文献
194.
The temperature transfer matrix equations for three fluid separate type heat pipe heat exchangers with the same and different heat transfer area in each heat pipe row are obtained by establishing an analytical heat transfer model in the co current or countercurrent flow mode. Using the temperature transfer matrix equations of exchanger with the each row heat transfer area is similar. The relationships of heat exchanger effectiveness θ1, θ2 with M, NTU, U, Δti are derived in the co current or countercurrent flow mode. For the designing and checking calculation of the heat recovery device for the large hot blast stove in steel plant, the theoretical results can be used and it is proved correct in practical application. 相似文献
195.
以万寿菊中的黄色素为研究对象,对影响超临界CO2流体萃取万寿菊黄色素的萃取温度、萃取压力和萃取时间分别进行了单因素研究。通过响应面最终确定最佳萃取条件为:萃取温度为60℃,萃取压力为48.6MPa,萃取时间为180min。在此条件下,万寿菊黄色素的最高得率为8.44mg/g,验证试验值为8.41mg/g,与预测值相对误差为0.36%。因此响应面法可以优化超临界萃取万寿菊黄色素工艺条件。 相似文献
196.
Inhibin is a heterodimeric glycoprotein hormone involved in the regulation of FSH release from the anterior pituitary gland and it has been characterized from various animals. Although, multiple molecular forms of inhibin have been reported from different species, however, the molecular nature of inhibin has not been studied in buffaloes. In the present study, attempts were made to identify inhibin in buffalo ovarian follicular fluid. Buffalo ovaries were obtained from the local abattoir and follicular fluid was aspirated from surface follicle (with diameter ?5 mm). A combination of techniques (viz., gel filtration, SDS-PAGE, Western blot etc.) was employed for identification and isolation of inhibin(s). Inhibin bands were detected at 129 and 63 kDa by Western blot analysis in non-reducing conditions. In reduced SDS-PAGE, 63 kDa fraction produced a single band while 129 kDa fraction resolved into four components of 63, 43, 29 and 20 kDa. Out of them only 29, 63 and the native 129 kDa fractions produced bands on Western blot analysis. In total five fractions (63, 54, 39, 29, 25 kDa) were obtained by trypsin digestion of 129 kDa form. However, only 63 and 29 kDa fractions showed immunoreactivity. In this study, for the first time, we have identified two major forms of inhibin (129 and 63 kDa) with little proteolytic cleavage/processing of the large precursor in the buffalo follicular fluid. 相似文献
197.
Shanon M. Zabolotzky Karen M. Vernau Philip H. Kass William Vernau 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(1):90-95
Background: Myelin‐like material in canine cerebrospinal fluid (CSF) specimens has been attributed to demyelinating or myelomalacic conditions. In our experience, myelin‐like material is observed frequently, especially in lumbar samples, and in a variety of disease conditions. Objectives: The objective of this study was to determine if there are associations between the presence of myelin‐like material and CSF collection site, body weight, underlying disease, and patient outcome. Methods: Wright–Giemsa‐stained cytocentrifuged specimens of CSF from the cerebellomedullary cistern (n=51) and lumbar cistern (n=47) of 98 dogs with neurologic disease were evaluated retrospectively for the presence and amount of extracellular myelin‐like material. Results were compared based on collection site, body weight, type of neurologic disease, and outcome. Results: Myelin‐like material was observed in 20/98 (20%) samples and was more frequently observed in lumbar (17/47, 36%) than cerebellomedullary samples (3/51, 6%) (P=.0028). Samples from dogs <10 kg were more likely to contain myelin (14/36, 39%) compared with dogs ≥10 kg (5/60, 8%) (P=.0052). Larger amounts of myelin‐like material were observed in CSF from dogs with intervertebral disk disease compared with other diseases (P=.045). No association was found between myelin‐like material and outcome. Conclusion: The association of extracellular myelin‐like material in canine CSF samples with sampling site and body weight suggests it is more often an artifact of collection technique and anatomy rather than the result of neurologic disease. Myelin‐like material in CSF is not associated with a poorer prognosis. 相似文献
198.
Reasons for performing study: The influence of synovial fluid culture on short‐ and long‐term prognosis of cases with septic synovitis requires study. Hypotheses: Horses with a positive bacterial culture from septic synovial fluid are less likely to survive or return to successful athletic function than those with a negative bacterial culture from septic synovial fluid. Methods: Records of mature horses presented to 2 equine referral hospitals for investigation of suspected septic synovitis were examined. Horses (n = 206) were included in the study if synovial fluid was submitted for full laboratory examination, including bacterial culture. A diagnosis of septic synovitis was based on a nucleated cell count >30 × 109 cells/l or >90% neutrophils and other clinical, cytological and bacteriological parameters. Long‐term follow‐up was obtained by telephone questionnaire. Univariate analysis, using the Fisher's exact test, was used for all outcomes. Results: Fourteen (20.9%) of 67 horses with a positive bacterial culture from synovial fluid were subjected to euthanasia because of persistent synovial sepsis compared to 2 (1.44%) of 139 with negative bacterial cultures (P<0.001). Overall survival and successful long‐term return to function in horses with a positive bacterial culture was 50% (24/48 horses) compared to 70.5% (74/105) in culture negative horses (P = 0.01). In horses that survived to be discharged, successful long‐term return to function was not significantly different between culture positive and culture negative groups. Growth of Staphylococcus aureus from synovial fluid did not affect short‐term survival to discharge from the hospital compared to other positive bacterial culture; however, successful long‐term return to function was only 30.4% (4/13) in horses from which S. aureus was cultured compared to 73.9% (17/23) of horses in which other bacteria were cultured (P = 0.015). Conclusions and potential clinical relevance: Horses with a positive bacterial culture from a septic synovitis have a poorer prognosis for survival to discharge from hospital and overall long‐term return to function than horses that yielded no bacterial growth. When S. aureus was cultured, the long‐term prognosis was poorer. 相似文献
199.
Etsuko KASUYA Ken‐ichi YAYOU Tsutomu HASHIZUME Sayuki KITAGAWA Madoka SUTOH 《Animal Science Journal》2010,81(3):345-351
To clarify the role of serotonin (5‐HT) in the regulatory mechanism of L‐tryptophan (TRP)‐induced growth hormone (GH) secretion in cattle, changes in 5‐HT concentrations in the cerebrospinal fluid (CSF) in the third ventricle (3V) and GH in plasma before and after the peripheral infusion of TRP were determined simultaneously. The direct effect of TRP on GH release from the dispersed anterior pituitary cells was also assessed. A chronic cannula was placed in 3V by stereotaxic surgery, then CSF and blood were withdrawn under physiological conditions. TRP (38.5 mg/kg BW) was infused through an intravenous catheter from 12.00 to 14.00 hours and CSF and blood sampling were performed from 11.00 to 18.00 hours at 1‐h intervals. The concentration of 5‐HT in CSF was determined by high‐performance liquid chromatography with electrochemical detection. GH, melatonin (MEL), and cortisol (CORT) concentrations were measured by radio‐immunoassay and enzyme‐immunoassay. Concentrations of 5‐HT were increased by TRP infusion. The TRP infusion significantly increased GH release. On the other hand, TRP did not stimulate GH release from the bovine pituitary cells. MEL and CORT concentrations were not altered by TRP infusion. These results suggest that TRP induced GH release via the activation of serotonergic neurons in cattle. 相似文献
200.