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151.
The effects of long-term athletic training are associated with excessive skeletal muscle turnover attributable to increased rates of myofibrillar protein synthesis and proteolysis, which are mechanisms poorly understood in the athletic dog. A physiologic field study using 44 English pointers and Labrador retrievers that had been purposely bred for bird hunting and retrieving was conducted to examine changes in the ubiquitin-proteasome (UP) pathway, which has been implicated in exercise-induced proteolysis. Muscle biopsy samples were collected from all dogs in September (preseason, pretraining) and February (peak season, peak activity). Western blot analysis was used to assess changes in expression of various components of the UP pathway in the biopsy samples. Citrate synthase and glycogen levels were also measured in a subset of these samples. Results across the population indicated pronounced up-regulation of ubiquitinated conjugates and the p31 regulatory capping subunit during the peak hunting period compared with the preseason period. In contrast, the catalytic core of the proteasome (beta-subunits) showed no apparent up-regulation in response to increased physical activity. Increased physical activity during the hunting season was associated with increased muscle glycogen levels and citrate synthase activity in these dogs. Overall, up-regulation of specific components of the UP pathway was an indication that it plays a role in the proteolytic process associated with skeletal muscle turnover during long-term athletic training, as previously believed.  相似文献   
152.
Data are lacking in the literature regarding the incidence of osteochondrosis (dissecans) [OC(D)] in relation to lameness evaluation in Dutch Warmblood horses. The objective of this retrospective study was to assess the incidence of radiological abnormalities consistent with osteochondrosis or osteochondrosis dissecans in 1,231 sound Dutch Warmblood (DW) horses presented for pre-purchase examination. Standardised (Dutch) pre-purchase examination protocols were evaluated. The pre-purchase examination included a clinical, lameness and radiological evaluation, performed at a private equine clinic in the Netherlands. Radiographical examination included views of the distal (DIP) and proximal (PIP) interphalangeal, metacarpo- and metatarsophalangeal (MCP/MTP), tarsocrural (TC) and femoropatellar (FP) joints. Radiographical evidence of OC(D) was found in 44.3% of clinically sound DW horses. In this study, 443 horses (36%, n = 1,231) had evidence of OCD and 102 horses (8.3%, n = 1,231) had evidence of OC on pre-purchase radiographs. The results also indicated that the TC joints were significantly more likely to be affected. A considerable number of horses did not demonstrate any lameness, although radiographs revealed OC(D).  相似文献   
153.
The effect of mixing has been tested on the extractable activities of lipoxygenase, peroxidase, and catalase from dough after 2, 5, and 20 min of mixing, and 30 min of rest period after 20 min of mixing. Different mixing conditions have been studied including temperature, atmosphere, speed, amount of water added to the dough, buffer solutions between pH 3.6 and 7.5 added to the dough, and different additives (linoleic acid, guaiacol, hydrogen peroxide, ascorbic acid, cysteine, yeast, and sodium chloride). In all the mixing conditions tested, the dough peroxidase activity remains equivalent to the initial flour activity, whereas losses in lipoxygenase and catalase activities largely varied according to mixing conditions. The results show that a self-destruction mechanism as well as physicochemical denaturation are responsible for these losses. Lipoxygenase losses seem mainly associated with the former mechanism, whereas catalase losses are highly increased in acidic conditions (physicochemical denaturation). Therefore, the relative impact of the three oxidoreducing enzymes may be largely modulated by mixing conditions.  相似文献   
154.
155.
The management of diabetes mellitus mandates measurement of blood glucose. Saliva offers an alternative to blood sampling, but measurement of the salivary glucose concentration is difficult, and the blood-to-saliva glucose time lag is uncertain. We aimed to determine the serum–saliva glucose time lag in the saliva of healthy dogs. The combined duct of the mandibular and sublingual salivary glands of 6 dogs was cannulated to collect saliva and prevent glucose degradation by oral bacteria. Following a 0.25 g/kg IV bolus of dextrose, paired serum–saliva samples were collected at baseline and in twelve 5-min blocks over 60 min. Serum and salivary glucose levels were analyzed with a linear mixed model for repeated measures with a compound symmetry error structure. Mean (±SD) saliva production was 10.3 ± 2.9 µL/kg/min, and the area under the curve (AUCglucose)saliva/serum ratio was 0.006, which highlights the magnitude of the large difference in glucose concentration between the 2 compartments. The serum–saliva glucose time lag was 30–40 min.  相似文献   
156.
Two experiments were performed to evaluate the effects of bismuth subsalicylate (BSS) and calcium-ammonium nitrate (CAN) on in vitro ruminal fermentation, growth, apparent total tract digestibility of nutrients, liver mineral concentration, and carcass quality of beef cattle. In Exp. 1, four ruminally cannulated steers (520 ± 30 kg body weight [BW]) were used as donors to perform a batch culture and an in vitro organic matter digestibility (IVOMD) procedure. Treatments were arranged in a 2 × 2 factorial with factors being BSS (0 or 0.33% of substrate dry matter [DM]) and CAN (0 or 2.22% of substrate DM). In Exp. 2, 200 Angus-crossbred steers (385 ± 27 kg BW) were blocked by BW and allocated to 50 pens (4 steers/pen) in a randomized complete block design with a 2 × 2 + 1 factorial arrangement of treatments. Factors included BSS (0 or 0.33% of the diet DM) and nonprotein nitrogen (NPN) source (urea or encapsulated CAN [eCAN] included at 0.68% or 2.0% of the diet, respectively) with 0.28% ruminally available S (RAS). A low S diet was included as a positive control containing urea (0.68% of DM) and 0.14% RAS. For Exp. 1, data were analyzed using the MIXED procedure of SAS with the fixed effects of BSS, CAN, BSS × CAN, and the random effect of donor. For Exp. 2, the MIXED procedure of SAS was used for continuous variables and the GLIMMIX procedure for categorical data. For Exp. 1, no differences (P > 0.230) were observed for IVOMD. There was a tendency (P = 0.055) for an interaction regarding H2S production. Acetate:propionate increased (P = 0.003) with the addition of CAN. In Exp. 2, there was a NPN source effect (P = 0.032) where steers consuming urea had greater carcass-adjusted final shrunk BW than those consuming eCAN. Intake of DM (P < 0.001) and carcass-adjusted average daily gain (P = 0.024) were reduced by eCAN; however, it did not affect (P = 0.650) carcass-adjusted feed efficiency. Steers consuming urea had greater (P = 0.032) hot carcass weight, and a BSS × NPN interaction (P = 0.019) was observed on calculated yield grade. Apparent absorption of S decreased (P < 0.001) with the addition of BSS. Final liver Cu concentration was reduced (P = 0.042) by 58% in cattle fed BSS, indicating that BSS may decrease Cu absorption and storage in the liver. The results observed in this experiment indicate that BSS does not have negative effects on feedlot steer performance, whereas CAN may hinder performance of steers fed finishing diets.  相似文献   
157.
The Isavirus is an orthomyxovirus with a genome composed of eight segments of negative single-strand RNA (−ssRNA). It has been proposed that the eight genomic segments of the Isavirus are organized as a ribonucleoprotein (RNP) complex called a minigenome, which contains all the viral RNA segments, a viral heterotrimeric polymerase and multiple copies of the viral nucleoprotein (NP). Here, we develop an Isavirus minigenome system and show the importance of the formation of active RNPs and the role of viral NP R189, R194, R302 and K325 residues in the NP RNA-binding domain in the context of RNPs. The results indicate it is possible to generate a minigenome in salmon cells, a composite ISAV RNPs with EGFP-based chimeric vRNA with heterotrimeric polymerase (PB1, PB2, PA) and NP protein using CMV-based auxiliary plasmids. It was also shown that NP R189, R194, R302 and K325 residues are important to generate viral mRNA from the constituted RNPs and a detectable reporter protein. This work is the first salmon cell-based minigenome assay for the Isavirus, which was evaluated by a bioinformatic and functional study of the NP protein in viral RNPs, which showed that correct NP-vRNA interaction is key to the functioning of RNPs.  相似文献   
158.

Background  

The concept of metabolite profiling has been around for decades and technical innovations are now enabling it to be carried out on a large scale with respect to the number of both metabolites measured and experiments carried out. However, studies are generally confined to polar compounds alone. Here we describe a simple method for lipophilic compounds analysis in various plant tissues.  相似文献   
159.
Growth, net production, and survival rates of milkfish cultured with Gracilariopsis bailinae at two stocking density combinations (T1– 30 fingerlings 100‐m?2 pond+1‐kg G. bailinae 4‐m?2 net cage, T2– 30 fingerlings 100‐m?2 pond+2‐kg G. bailinae 4‐m?2 net cage) in brackish water earthen ponds over four culture periods were determined. The control (T3) was stocked at 30 fingerlings 100‐m?2 pond. Specific growth and production rates of G. bailinae were also calculated. There were no significant differences in mean growth, survival, and net production rates of milkfish between the three treatments. Irrespective of stocking singly or in combination with G. bailinae, significantly higher mean growth and mean production rates for milkfish were obtained during the third culture period of year 1 than those obtained from the other culture periods. Survival rates were not significantly different among the four culture periods. There were no significant differences in mean specific growth and mean net production rates between the two stocking densities of G. bailinae. Significantly higher mean specific growth and mean net production rates of red seaweed were also obtained during the third culture period of year 1 than those obtained from other culture periods. The production of milkfish and red seaweed was higher during the dry season. Growth rates of milkfish was positively correlated with temperature and salinity, while net production rates were positively correlated with temperature and total rainfall, but was inversely correlated with dissolved oxygen. G. bailinae growth and net production rates were positively correlated with water temperature and salinity. Results show that milkfish can be polycultured with G. bailinae grown in net cages in brackish water ponds at stocking density combination of 30 fingerlings 100‐m?2 pond+1‐kg G. bailinae 4‐m?2 net cage.  相似文献   
160.
This study was conducted to quantify and characterize the mycoflora associated with the ‘green water’ culture system of Penaeus monodon. Samples of water, tilapia gut and mucus, and shrimp hepatopancreas from three shrimp farms were collected during 15, 30, 45 and 60 days of culture (DOC). Results showed that high fungal loads were observed in tilapia gut (total: 117–1352 colony forming unit (CFU) 5 cm hind gut?1; yeasts: 0–136 CFU 5 cm hind gut?1) and mucus (total: 12–311 CFU (5 cm2)?1; yeasts: 0–88 CFU (5 cm2)?1), while minimal fungal populations were observed in water samples (total: 0–110CFU mL?1; yeasts: 0–5 CFU ml?1). Shrimp hepatopancreas harboured a very low number of filamentous fungi (0–27 CFU 0.1 g?1) and yeasts (0–7CFU 0.1 g?1) especially at 60 DOC. The filamentous fungal isolates were dominated by Penicillium and Aspergillus species, while the yeast populations were dominated by Rhodotorula and Saccharomyces species. The dominance of these fungi on tilapia mucus and gut and their presence in the rearing water might play an important role in the overall mechanisms involved in the control of luminous Vibrio in the ‘green water’ grow‐out culture of P. monodon.  相似文献   
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