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161.
Indonesia is one of the largest teak timber producers in the world. The Javanese State Forest Company has been a major producer of teak timber in Indonesia; however, log production decreased drastically due to severe illegal logging after the collapse of Suharto regime. In contrast, small-scale private forests (PFs) owned by local farmers have expanded and are expected to be a new source of teak timber. Long rotation is a critical factor in producing a larger diameter log with a higher heartwood proportion. However, harvest timing in PFs is traditionally decided based on individual farmers’ needs even if trees are still young and of small diameter. Therefore, traditional harvesting is an obstacle to producing high-quality teak timber. The objectives of this study are to (1) identify the household economies and PF management styles of local farmers, (2) characterize the local farmers who conduct traditional harvesting, and (3) suggest key considerations for PF policymaking. Key informant interviews and semi-structured interviews with local farmers were conducted in three villages in Gunungkidul district, Yogyakarta Special Region. The study identified the household economies, the ownership and management structures, and the traditional harvesting in PFs in the three villages, and reaffirmed diversity and complexity of PFs. It appears that PF management is influenced by topographic and socioeconomic conditions and differs widely across villages. Therefore, it is important to consider the diversity and complexity of PFs in PF policymaking.  相似文献   
162.
The role of phytohormones in tracheid formation remains unclear in conifers. In this study, to obtain information on the role of auxin (IAA) and gibberellin A4 (GA4), we examined seasonal variation in the amount of phytohormones in cambial-region tissues and tracheid formation of sugi cultivar planted in a Nelder plot with different tree densities. We demonstrated that the amount of IAA was positively correlated with the number of tracheids formed in early and mid-season, but not in late season, and had no relation to tracheid differentiation. Crown length and height at the crown base had a positive and negative effect, respectively, on IAA amounts in early and mid-season, but not in late season. Height-to-diameter ratio was negatively correlated with IAA amounts in early and mid-season, but not in late season. Sugi trees with wider spacing continued tracheid formation in late season with smaller amounts of IAA, although the trees with narrower spacing ceased tracheid formation with larger amounts of IAA. Cambial growth cessation in late season might be controlled not by IAA amount, but by short-day-induced insensitivity to IAA. GA4 had no relation with the indexes of growth traits or tracheid formation.  相似文献   
163.
In striated muscles, approximately 300 myosin molecules form a single thick filament in myofibrils. Each myosin is continuously displaced by another myosin to maintain the thick filament structure. Our previous study using a fluorescence recovery after photobleaching (FRAP) technique showed that the myosin replacement rate is decreased by inhibition of protein synthesis, but myosin is still exchangeable. This result prompted us to examine whether myosin in the cytoplasm is involved in myosin replacement in myofibrils. To address this, FRAP was measured in green fluorescent protein (GFP)‐tagged myosin heavy chain 3 (Myh3) expressing myotubes that were treated with streptolysin‐O (SLO), which forms pores specifically in the plasma membrane to induce leakage of cytoplasmic proteins. Our biochemical data demonstrated that the cytoplasmic myosin content was reduced in SLO‐permeabilized semi‐intact myotubes. Furthermore, FRAP experiments showed a sluggish substitution rate of GFP‐Myh3 in SLO‐permeabilized myotubes. Taken together, these results demonstrate that the myosin substitution rate is significantly reduced by a decreased amount of myosin in the cytoplasm and that cytoplasmic myosin contributes to myosin replacement in myofibrils.  相似文献   
164.
Titanium columns (Ti-6A1-4V) were treated with arc-deposition to roughen the surface enough to anchor the bone, and then coated with hydroxyapatite (HA) at a thickness of 5 micro m by the sputtering technique. Columns were implanted into dog femurs, and fixation of columns to bone due to bone-ingrowth was assessed histologically and with the push-out test. The HA-coated columns were inserted in the shafts of the right femurs of 2 dogs. As a control, columns that were only arc-deposited (non-coated columns) were inserted into the left femurs. The interfacial strength was higher for the HA-coated columns than for the non-coated columns. Coating a rough surface with an HA layer using a sputtering technique reinforces interfacial strength between bone and implants.  相似文献   
165.
To determine the acute effects of carvedilol (beta-blocker) on cardiovascular and renal function and its pharmacokinetics in dogs. Fifteen mature mongrel dogs (7-15 kg) of both sexes were used in these experiments. Eight dogs served as controls, and seven dogs served as iatrogenic mitral regurgitation (MR) experimental animals. Carvedilol (0.2, 0.4, and 0.8 mg/kg, P.O.) was administered, and the blood carvedilol concentration was analyzed by reverse-phase high-performance liquid chromatography. The response to isoproterenol or phenylephrine was also evaluated. Isoproterenol (0.025 microg/kg/min) was infused via the saphenous vein for 5 min, and phenylephrine (5 microg/kg) was injected with carvedilol (0.2, 0.4 mg/kg) or placebo for 4 days. The heart rate and arterial blood pressure were measured, and LV fractional shortening was measured by echocardiography. Glomerular filtration rate (GFR) and renal plasma flow (RPF) were measured by intravenous infusion of sodium thiosulfate and sodium para-aminohippurate. Carvedilol (0.2 mg/kg) decreased the heart rate, whereas renal function, arterial blood pressure, and left ventricular contractile function were not affected. Carvedilol (0.4 mg/kg) decreased heart rate, blood pressure, and renal function. The tachycardic response to isoproterenol was significantly diminished for 36 hr by 0.4 mg/kg carvedilol. Carvedilol 0.2 mg/kg inhibited this effect for 24 hr. Thus, it is necessary to titrate the dosage of carvedilol, it should be initiated at less than 0.2 mg/kg and titrated up to 0.4 mg/kg for heart failure dogs.  相似文献   
166.
Changes in hip joint congruity was evaluated in dogs with hip dysplasia before and after triple pelvic osteotomy by computed tomography examination in the standing position. Lateral center edge angle significantly increased, and center distance (CD) significantly decreased after surgery compared to the values before surgery, respectively. There was an inverse proportion between the postoperative period and the change in the ratio of CD. These results suggested that joint laxity was improved with time after surgery, providing evidence of the clinical usefulness of this surgery.  相似文献   
167.
The infection status of 15 viruses in 120 pigs aged about 6 months was investigated based on tonsil specimens collected from a slaughterhouse. Only 5 species of porcine parvoviruses and porcine circovirus type 2 (PCV2) were detected at high frequencies; 67% for porcine parvovirus (PPV) (PPV-Kr or -NADL2 as the new abbreviation), 58% for PPV2 (CnP-PARV4), 39% for PPV3 (P-PARV4), 33% for PPV4 (PPV4), 55% for PBo-likeV (PBoV7) and 80% for PCV2. A phylogenetic analysis of PPV3 suggested that Japanese PPV3s showed a slight variation, and possibly, there were farms harboring homogeneous or heterogeneous PPV3s. Statistical analyses indicated that the detection of PCV2 was significantly coincidental with each detection of PPV, PPV2 and PPV3, and PPV and PPV4 were also coincidentally detected. The concurrent infection with PCV2 and porcine parvoviruses in the subclinically infected pigs may resemble the infection status of pigs with the clinical manifestations of porcine circovirus associated disease which occurs in 3–5 months old pigs and is thought to be primarily caused by the PCV2 infection.  相似文献   
168.
Successful regeneration and remodeling of neuromuscular junctions are critical for restoring functional capacities and properties of skeletal muscle after damage, and axon‐guidance molecules may be involved in the signaling that regulates such restoration. Recently, we found that early‐differentiated satellite cells up‐regulate a secreted neural chemorepellent Sema3A upon in vivo muscle‐crush injury. The study also revealed that Sema3A expression is up‐regulated in primary satellite‐cell cultures in response to hepatocyte growth factor (HGF) and basic fibroblast growth factor (FGF2) and is prevented by transforming growth factor (TGF)‐β2, 3. In order to verify the physiological significance of this regulation in vitro, the present study was designed to estimate the time‐course of extracellular HGF, FGF2 and TGF‐β3 concentrations after crush‐injury of Gastrocnemius muscle in the rat lower hind‐limb, using a combination of a non‐homogenization/non‐spin extraction of extracellular wound fluids and enhanced chemiluminescence–Western blotting analyses. Results clearly demonstrated that active HGF and FGF2 are prevalent in 2–8 days post‐crush, whereas active TGF‐β3 increases after 12 days, providing a better understanding of the time‐coordinated levels of HGF, FGF2 and TGF‐β3 that drive regulation of Sema3A expression during regenerative intramuscular moto‐neuritogenesis.  相似文献   
169.
An apple orchard consisting of a single cultivar under the condition of natural pollination must have suitable pollinizers such as Crab apples to ensure stable fruit production. We selected ‘Maypole’ and ‘Dolgo’ as pollinizers for the cultivar ‘Fuji’, and investigated the rate of fruit and seeds in ‘Fuji’ fruits produced by pollen of the pollinizers. We developed a method for tracing pollen flow based on the leaf color of progeny and S-RNase allele of ‘Maypole’, and on Simple Sequence Repeat (SSR) analyses of ‘Maypole’ and ‘Dolgo’. These were powerful tools for determining the distance insects (mainly Osmia cornifrons) carry pollen from the pollinizers to ‘Fuji’. Although the fruit set of ‘Fuji’ apples was not reduced with increasing distance between ‘Fuji’ apple trees and pollinizers (probably due to pollen flow from other commercial cultivars planted outside the area), the rate of ‘Fuji’ apple fruit produced by the pollen of the pollinizers decreased with increasing distance. The rate of fruit produced by the pollinizers was 84% and 77% when ‘Fuji’ was 2.5 m from ‘Maypole’ and ‘Dolgo’, respectively, and 71% and 64% when ‘Fuji’ was 5 m from ‘Maypole’ and ‘Dolgo’, respectively, but was reduced to 47% and 39% when ‘Fuji’ was 10 m from ‘Maypole’ and ‘Dolgo’, respectively. However, the spacing could cause reduced fruit size, and require extra fruit thinning for producing large fruits. It could also cause reduction of the yield for increasing the planting area of pollinizers. We recommend that pollinizers should be planted not more than 10 m from ‘Fuji’.  相似文献   
170.
Abstract

In this report, we propose a new method of evaluating the effect of nitrogen deposition on forest ecosystems, namely the spatial variation in nitrogen deposition enables to detect readily the effect of anthropogenic N deposition on biogeochemical processes in forest ecosystems. We analyzed the nitrogen deposition (throughfall fluxes) and stream water chemistry over five adjacent small catchments in which soil types (Hapludants) and vegetation composition (50 to 60 years old larch plantation) were fairly identical. Thirty-two throughfall collectors were set up in the five catchments (six to eight collectors in each catchment) and throughfall samples were collected after a rain event, while stream water samples were collected once or twice a month. The monitoring was carried out during a period of 6 months (2002 June to 2002 November). Throughfall dissolved inorganic nitrogen (DIN) fluxes were highly variable: the highest N input, 1.32 kg N ha?1 6 months?1, was sixty-six times higher than the lowest input, 0.02 kg N ha?1 6 months?1. The mean DIN inputs and the mean nitrate concentrations in streams showed a three-time variation across the five catchments. In addition, the DIN inputs showed a high correlation with the stream nitrate concentrations (r = 0.88).  相似文献   
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