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441.
ABSTRACT: The rate of oxygen consumption and energetic cost of locomotion of captive harbor porpoises Phocoena phocoena were studied in Hokkaido, Japan, using respirometry together with externally attached devices (a data logger) that recorded swim speed and dive depth. Harbor porpoises swam freely in a tank at a swim speed ranging 0.5–4.2 m/s. Swimming during most dives was relatively slow with mean swim speed being 0.76–0.91 m/s. Oxygen consumption rate of the swimming harbor porpoise increased with swim speed according to a cubed function. The minimum cost of transport during underwater swimming in the harbor porpoise was 2.39–2.43 J/kg per m at an average swim speed of 1.3–1.5 m/s. However, porpoises usually swam slower to conserve energy and dived aerobically. This explains why harbor porpoises can dive repeatedly and continuously without extended rest at the sea surface.  相似文献   
442.
Functional traits are an important aspect of long‐term breeding strategies for dairy cattle. In this regard, it is necessary to develop simple methods for estimating the economic value of herd life. In this study, the economic daily value of herd life was estimated when survival rate varied between ?0.05 and 0.05 from the basal survival rate. The extension days per survival rate were 26.5 days in Hokkaido and 20.3 days in other regions. The increases in values of annual income per day of herd life were 95.18 yen in Hokkaido and 101.80 yen in other regions. The relative economic weights of milk yield to herd life per genetic standard deviation were 0.668 in Hokkaido and 1.03 in other regions. Estimated increments in yearly profits based on young sire selection for herd life were 963 yen in Hokkaido and 1,030 yen in other regions. The estimated increments in annual profits based on young sire selection for milk yield were 1,268 yen in Hokkaido and 2,097 yen in other regions. Given that economic value was linearly correlated with herd‐life length, the linear regression coefficients between these factors could be used to estimate the economic value of herd‐life length.  相似文献   
443.
444.
Calcitonin gene-related peptides (CGRP), which are potent vasodilators, are elevated during cardiopulmonary bypass (CPB) in humans. We evaluated the plasma levels of CGRP in dogs during CPB with hemofiltration with and without hemodilution. Female beagles were divided into control (n=5) and hemodilution (n=5) groups. The CPB with hemofiltration was performed with or without hemodilution. For the measurement of CGRP, blood samples were collected pre-CPB, during CPB, and post-CPB. The concentrations of CGRP in the hemofiltration solution were measured. Although the CPB elevated the plasma CGRP levels in both groups, its elevation was significant in the hemodilution group when compared to the pre-CPB levels. CGRP levels returned to normal post-CPB. Significant differences were found between the two groups in the CGRP amount in hemofiltration. The results show that hemofiltration should be used during CPB to decrease the plasma levels of CGRP.  相似文献   
445.
Simultaneous treatments with Cd and arsenic (arsenite and arsenate) led to the synergistic growth inhibition of tobacco (Nicotiana tabacum cv. BY-2) cells. Cd contents in cells increased by co-treatment with arsenic for 24 h. The amount of total phytochelatins (PCs) per unit of Cd in the cells treated with Cd and arsenate was lower than that in the cells treated with Cd alone. Simultaneous treatments with Cd and arsenic promoted the induction of the biosynthesis of (γ-Glu-Cys)2-Gly and inhibited the induction of the biosynthesis of (γ-GluCys)3-Gly and (γ-Glu-Cys)4-Gly, compared with the treatment with Cd alone. Consequently, since the inhibition of PC biosynthesis led to the increase of the cellular concentration of putative ionic (= toxic) Cd, cell growth was inhibited synergistically by simultaneous treatments with Cd and arsenic. In addition, based on the results showing that buthionine sulfoximine increased the sensitivity to arsenite and arsenate, that PC biosynthesis was induced by treatment with arsenite or arsenate, it is suggested that glutathione and/or its metabolic products such as PCs are involved in arsenic tolerance.  相似文献   
446.
Abstract

Submerged paddy soil with powdered rice straw was incubated anaerobically. In the presence of 10 p.M of EDTA, the amount of Fe(II) significantly increased during the early stage of incubation. This finding suggests that EDTA extracted some part of Fe(III), which was utilized then by Fe(III)-reducing bacteria. These increase in the Fe(II) content was accompanied both by the suppression of sulfate-reduction and by the enhancement of acetic acid (AA}-decomposition. The addition of EDTA did not enhance the CH4 -production during the early stage of incubation. These findings suggest that the reduction of the EDTA-extractable Fe (III) resulted in electron deficiency and that the electron flow was mainly diverted from sulfate reduction to Fe(III)-reduction in the early stage of incubation. As a result of this electron deficiency, Fe(III)reducing bacteria may utilize AA as an electron donor. The addition of EDT A enhanced both the production and the decomposition of AA in the late stage of incubation as well as the CH4 -production. These facts suggest that the reduction of the EDTA-extractable Fe (III) in the early stage of incubation decreased the redox potential, which in turn shortened the duration of the lag period of the anaerobic reactions in the late stage.  相似文献   
447.
This study reported detailed clinical effects of bovine lactoferrin on 2 canine littermates (1 female and 1 male) with familial neutrophil dysfunction and an investigation of their genetic background. Clinical signs caused by severe upper respiratory bacterial infections were observed in these dogs. Oral administration of bovine lactoferrin for a long duration improved their clinical signs (severe uveitis in the female dog and coughing from pneumonia in the male dog). Their backcross dogs that have the same father didn't show clinical signs of bacterial infection. Neutrophil function tests revealed that the backcross dogs didn't have any disorders. It is likely that abnormal clinical signs are associated with neutrophil dysfunction in the colony, and the mother dog of these cases might be the genetic carrier of this dysfunction.  相似文献   
448.
449.
The aim of this study was to investigate the risk factors for tail chasing behaviour that occurs when a dog spins in tight circles to chase its tail, sometimes biting it. The behaviour is a sign of canine compulsive disorder (CD). A questionnaire about tail chasing behaviour and general information about the animals was used to collect data on seven breeds of pet dogs. The data were gathered at a dog event and at veterinary practices. To determine which variables were associated with tail chasing behaviour, stepwise multiple regression analyses were performed. Regardless of cohort, 'breed' and 'source of acquisition' were significantly associated with tail chasing behaviour. Using a chi-square test, the association between 'source of acquisition' and the behaviour was examined separately in two breeds (Shiba inu and Dachshund) that had the largest number of individuals chasing their tails accompanied by biting and/or growling at them. This factor showed a significant and consistent association across the two breeds. With respect to the risk factors of 'breed' and 'source of acquisition', high percentages of Shiba inu and dogs originating from pet stores were included in the group chasing their tails with biting and/or growling. The results suggest that distinct risk factors exist for tail chasing behaviour and such factors appear to be regulated by both genetics and the environment.  相似文献   
450.
We monitored variation in seasonal and annual net ecosystem production (NEP), gross primary production (GPP), and ecosystem respiration (R E) based on 7-year eddy covariance measurements above a cool?Ctemperate deciduous broad-leaved forest (Japanese beech forest). The 7-year means (±SD) of annual NEP, GPP, and R E were 312?±?64, 1250?±?62, and 938?±?36?g?C?m?2?year?1, respectively. Variation in NEP was much larger than variation in GPP and R E. During the growing season, the main factor controlling carbon balance was air temperature; variation in seasonal integrated NEP was regulated by accumulated air temperature (degree-day) with a significant negative correlation, whereas the seasonal ratio of R E to GPP was correlated positively with accumulated air temperature. Because the deviation of seasonal NEP was also significantly correlated with seasonal R E/GPP, NEP was controlled by R E/GPP, depending on air temperature during the growing season. Seasonal R E in the defoliation and snow seasons was also important for evaluating the annual carbon balance, because the total number of days in the two seasons was quite large owing to a long snowy winter. In the defoliation and snow seasons, we found defoliation season length was a major factor determining seasonal integrated R E, illustrating the positive correlation between R E and defoliation season length. The major factors controlling interannual variations in forest carbon balance are discussed.  相似文献   
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