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661.
Little is known about the effects of K(+) fertilization on pyruvate kinase (PK) activities in cucumber (Cucumis sativus L. cv. Brunex) grown in the greenhouse on calcareous soils. Here, the effect of K rates on the concentrations of K(+), Mg(2+), and Ca(2+) and on the PK activity as a possible indicator of the levels of these cations in the leaves and fruits of cucumber plants has been studied. The treatments consisted of applications of three rates of K in the form of K(2)SO(4) (K1 = 0.075 mg mL(-)(1), K2 = 0.15 mg mL(-)(1), and K3 = 0.30 mg mL(-)(1)). In general, K(+) application in calcareous soils proved beneficial. The highest application of K(+) (K3) to the culture medium reduced, in both the leaves and fruits, the foliar concentrations of Mg(2+) and Ca(2+). These results are reflected by the lowest basal PK activities and the highest differences between the basal PK activity and activities stimulated by these two cations. The opposite effect resulted with K2, with maximal basal PK activity and minimal differences between this activity and activities stimulated by the cations, indicating a better balance in this treatment between the different cations under the experimental conditions. Finally, this trend might partly account for the highest commercial yield in plants treated with K2.  相似文献   
662.
The objective of this paper was to evaluate romifidine as a premedicant in dogs prior to propofol-halothane-N2O anesthesia, and to compare it with the other alpha2-agonists (medetomidine and xylazine). For this, ten healthy dogs were anesthetized. Each dog received 3 preanesthetic protocols: atropine (10 microg/kg BW, IM), and as a sedative, romifidine (ROM; 40 microg/kg BW, IM), xylazine (XYL; 1 microg/kg, IM), or medetomidine (MED; 20 microg/kg BW, IM). Induction of anesthesia was delivered with propofol 15 min later and maintained with halothane and N2O for one hour in all cases. The following variables were registered before preanesthesia, 10 min after the administration of preanesthesia, and at 5-minute intervals during maintenance: PR, RR, rectal temperature (RT), MAP, SAP, and DAP. During maintenance, arterial oxygen saturation (SpO2), end-tidal CO2 (EtCO2) and percentage of halothane necessary for maintaining anesthesia (%HAL) were also recorded. Induction dose of propofol (DOSE), time to extubation (TE), time to sternal recumbency (TSR) and time to standing (TS) were also registered. The statistical analysis was carried out during the anesthetic period. ANOVA for repeat measures revealed no differences between the 3 groups for PR and RR; however, MAP, SAP and DAP were higher in the MED group; SpO2 was lower in MED and EtCO2 was lower in ROM; %HAL was higher in XYL. No statistical differences were observed in DOSE, TE, TSR or TS. Percentage of halothane was lower in romifidine and medetomidine than in xylazine premedicated dogs also anesthetized with propofol. All the cardiorespiratory variables measured were within normal limits. The studied combination of romifidine, atropine, propofol, halothane and N2O appears to be a safe and effective drug combination for inducing and maintaining general anesthesia in healthy dogs.  相似文献   
663.
Since the beginning of the 21st century, electronic monitoring (EM) has emerged as a cost‐efficient supplement to existing catch monitoring programmes in fisheries. An EM system consists of various activity sensors and cameras positioned on vessels to remotely record fishing activity and catches. The first objective of this review was to describe the state of play of EM in fisheries worldwide and to present the insights gained on this technology based on 100 EM trials and 12 fully implemented programmes. Despite its advantages, and its global use for monitoring, progresses in implementation in some important fishing regions are slow. Within this context, the second objective was to discuss more specifically the European experiences gained through 16 trials. Findings show that the three major benefits of EM were as follows: (a) cost‐efficiency, (b) the potential to provide more representative coverage of the fleet than any observer programme and (c) the enhanced registration of fishing activity and location. Electronic monitoring can incentivize better compliance and discard reduction, but the fishing managers and industry are often reluctant to its uptake. Improved understanding of the fisher's concerns, for example intrusion of privacy, liability and costs, and better exploration of EM benefits, for example increased traceability, sustainability claims and market access, may enhance implementation on a larger scale. In conclusion, EM as a monitoring tool embodies various solid strengths that are not diminished by its weaknesses. Electronic monitoring has the opportunity to be a powerful tool in the future monitoring of fisheries, particularly when integrated within existing monitoring programmes.  相似文献   
664.
665.
Cholesterol is a necessary element in the diet of prawns and it is involved in the metabolic processes of sexual maturation and synthesis of the molting hormone. Freshwater prawns are not able to synthesise cholesterol from specialised metabolic pathways. The aim of this study was to describe changes in structural and morphometric patterns of hepatopancreas associated with morphotypic differentiation of males Macrobrachium amazonicum when fed with different levels of cholesterol. Considering the four morphotypes of this species, Translucent Claw morphotype specimens were split into experimental units and divided into four groups, fed with different levels of cholesterol (0%, 0.5%, 1%, 2%) for 50 days. They were collected as they reached Green Claw (GC) morphotype, weighed to determine the hepatosomatic index, and the hepatopancreas was processed in histological routine for morphologic and morphometric analysis. In this study, it was possible to observe that the 2% cholesterol treatment exhibited more animals that reached the GC morphotype, and there was no significant weight gain in all treatments. Histologically, B‐cell abundance and hypervacuolized as well as F‐ and R‐cells shortages were observed as the percentage of cholesterol increased. This alteration in cellular profile correlates with the morphometric analyses that exhibited an increase in epithelial area and alterations in the lumen shape. This imbalance observed in the lumen‐epithelium relationship may be associated with a low digestive performance and possibly congested the functions of hepatopancreas. Thus, high doses of cholesterol promoted morphotypic differentiation without weight gain, due to alterations on hepatopancreas.  相似文献   
666.
Hepatitis E virus (HEV) is the causative agent of an acute and in most cases self‐limiting hepatitis. Of the four major HEV genotypes that infect humans, genotype 3 and 4 are zoonotic and have been identified in humans but predominantly in pigs and wild boar, which are considered the main reservoirs. However, the known host range of zoonotic HEV may be increasing to comprise additional species, including companion animals. Several studies have identified contact with dogs as a risk factor for HEV infection in humans, yet information on the occurrence of HEV in Swiss dogs is lacking. To examine a possible risk of exposure, this study was designed to assess the seroprevalence of HEV in 84 Swiss dogs. Serum and plasma samples collected from four veterinary clinics were screened for HEV‐specific antibodies by HEV‐antibody ELISA test kit. In addition, information of 22 dogs regarding the country of origin, the type of dog feed and any history of hunting was recorded. Samples from seropositive animals were also screened for the presence of HEV RNA by quantitative real‐time RT‐PCR (qRT‐PCR). Overall, 38% (32 of 84) of the dogs tested seropositive for anti‐HEV, indicating exposure to HEV. Among the 22 dogs for which information was available, HEV‐specific antibodies were detected in three of five dogs that were born abroad, in one of two dogs that were fed a raw meat‐based diet, and in one hunting dog. No viral RNA could be detected in any of the serum and plasma samples; thus, the genotype of the strains remained undetermined. This study provides further evidence for canine exposure and susceptibility to HEV and highlights the need to further assess the risks of HEV transmission to humans with contact to dogs.  相似文献   
667.
668.
Plant Foods for Human Nutrition - Chaura (Gaultheria poeppigii) is a plant species native from Southern Chile, which produces a berry fruit with potential beneficial health effects due to its...  相似文献   
669.
During a long‐term 3‐year dietary exposure of mature carp females to lead, its bioaccumulation in the brain, changes in the neurohormonal activity at the level of the hypothalamus and the pituitary gland as well as the growth and maturation of ovaries were analysed. Moreover, an analysis of the effectiveness of hormone‐stimulated spawning during two subsequent spawning seasons was carried out. The results of the analyses show that chronic exposure of maturing and mature carp females to lead in feed results in its accumulation in the brain (1.365 μg g?1). This impairs the endocrine activity of the hypothalamus, which is manifested by, among others, an increased secretion of dopamine and impaired spontaneous secretion of luteinizing hormone (LH). The observed decrease in the concentration of gonadotropin in blood inhibits vitellogenesis, which is manifested by a lower degree of the maturity of oocytes, lower fecundity (as measured by egg number, egg weight, egg maturity and egg survival) and lower gonadosomatic index values. The final negative impact of lead is the impairment of reproductive functions, as manifested by a smaller number of spawning females and in their lower fecundity during spawning.  相似文献   
670.
BackgroundFeline pancreatic lipase immunoreactivity (fPLI) is commonly used to diagnose pancreatitis in cats (FP). Untargeted metabolomics has been extensively applied in human and veterinary medicine, but no metabolomic studies regarding FP have been conducted.ObjectivesTo identify metabolites significantly associated with increased fPLI.AnimalsForty‐nine client‐owned cats: 11 clinically healthy and 38 with various clinical conditions.MethodsAnalytical cross‐sectional study with convenience sampling. A panel of 630 metabolites belonging to 26 biochemical classes was quantified in plasma using a commercial metabolomic assay. The correlation between plasma metabolite concentrations and serum fPLI was evaluated using Spearman''s rank correlation coefficient (R s) with Bonferroni correction. Multivariable analysis then was performed to control for glomerular filtration rate, liver damage, and blood glucose concentration. The accuracy of selected metabolites in discriminating between cats with normal (≤3.5 μg/L) and increased (>5.3 μg/L) fPLI was estimated using the area under the receiver operating characteristic curve (AUROC).ResultsFour hundred and seven of 630 metabolites (64.6%) were quantified in all cats. When controlled for potential confounders only 3 sphingolipids were significantly positively correlated with fPLI: 2 cerebrosides: HexCer(d18:1/24:0); (R s = .56), and HexCer(d18:1/24:1); (R s = .58) and 1 sphingomyelin: SM C18:0 (R s = .55). Their AUROCs in identifying cats with increased fPLI were 82% (95% confidence interval [CI 95%], 70%‐94%), 84% (CI 95%, 72%‐96%), and 78% (CI 95%, 65%‐92%), respectively.Conclusions and Clinical ImportanceSelected sphingolipids are moderately positively correlated with fPLI and appear to have fair to moderate diagnostic accuracy in discriminating between cats with normal and increased fPLI.  相似文献   
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